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Sample records for intrapartum valsalva maneuver

  1. Clinical Presentation and Conservative Management of Tympanic Membrane Perforation during Intrapartum Valsalva Maneuver

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    Jonathan D. Baum

    2010-01-01

    Full Text Available Background. Tympanic membrane perforation may occur when ear pressures are excessive, including valsalva maneuver associated with active labor and vaginal delivery. A pressure differential across the eardrum of about 5 psi can cause rupture; the increased intraabdominal pressure spikes repeatedly manifested by “pushing” during second-stage labor easily approach (and may exceed this level. Material and Method. We describe a healthy 21-year old nulliparous patient admitted in active labor at 39-weeks' gestational age. Results. Blood appeared asymptomatically in the left ear canal at delivery during active, closed-glottis pushing. Otoscopic examination confirmed perforation of the left tympanic membrane. Complete resolution of the eardrum rupture was noted at postpartum check-up six weeks later. Conclusion. While the precise incidence of intrapartum tympanic membrane rupture is not known, it may be unrecognized without gross blood in the ear canal or subjective hearing loss following delivery. Only one prior published report on tympanic membrane perforation during delivery currently appears in the medical literature; this is the first English language description of the event. Since a vigorous and repetitive valsalva effort is common in normal vaginal delivery, clinicians should be aware of the potential for otic complications associated with the increased intraabdominal pressure characteristic of this technique.

  2. Levator co-activation is a significant confounder of pelvic organ descent on Valsalva maneuver.

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    Ornö, A K; Dietz, H P

    2007-09-01

    A Valsalva maneuver is used clinically and on imaging in order to determine female pelvic organ prolapse. We have examined the potential confounding effect of levator co-activation at the time of a Valsalva maneuver and the impact of repetition with biofeedback instruction. Fifty nulliparous women at 36-38 weeks' gestation received 3D/4D translabial ultrasound investigation in the dorsal resting position after bladder emptying. Valsalva maneuvers were recorded initially and after repeated attempts with visual biofeedback both during the maneuver and after, with the operator demonstrating findings on the ultrasound monitor, in order to abolish levator co-activation. Offline analysis was subsequently undertaken. Significant differences between first and optimal Valsalva maneuver were found for bladder neck position, bladder neck descent, hiatal sagittal diameter and hiatal area on Valsalva. In a minority of women (22/50) we observed a reduction in the sagittal hiatal diameter on first Valsalva maneuver, indicating levator co-activation. A reduction in sagittal diameter was seen in only 11/50 after instruction. Levator co-activation was associated with significantly lower bladder neck descent. The Valsalva maneuver is frequently accompanied by a pelvic floor muscle contraction. Levator co-activation may be a substantial confounder, reducing pelvic organ descent. Without repetition and digital, auditory or visual biofeedback, women may not perform a correct Valsalva maneuver. Biofeedback markedly reduces the likelihood of levator co-activation but does not abolish it completely. Copyright 2007 ISUOG. Published by John Wiley & Sons, Ltd.

  3. Effective Valsalva maneuvering during TCCD and unrevealed etiology of RLS.

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    Aparci, M; Guney Senol, M; Yalcin, M; Tansel Kendirli, M; Isilak, Z

    2016-04-01

    Either transcranial color-coded Doppler (TCCD) or contrast echocardiography (CE) is the bests of clinically applicable and reproducible methods to evaluate the functionality of right-to-left shunts that can be found in different localization on atrial septum. As the anatomical features of right-to-left shunts could vary in many forms, detection of RLS by functional tests may aid the clinician to do risk prediction and management of patients. Sensitivity of TCDD or CE can be increased by performing effective Valsalva maneuvering during the test procedure. Timing of RLS during the cardiac cycles may help interpreting about the etiology of RLS, atrial septum or intrapulmonary shunts. Intrapulmonary shunts have been recently reported to be associated with RLS and frequently overlooked unless the tests prolonged up to 10th cardiac beat. Migraine, cryptogenic strokes, and paradoxic embolism are closely associated with RLS which should be evaluated by the collaboration of cardiologists and neurologists. Success of diagnostic procedure depends on high suspicion of index for RLS and application of contrast-enhanced tests that are effectively performed at each step. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Proof of concept: differential effects of Valsalva and straining maneuvers on the pelvic floor.

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    Talasz, Helena; Kremser, Christian; Kofler, Markus; Kalchschmid, Elisabeth; Lechleitner, Monika; Rudisch, Ansgar

    2012-10-01

    To prove a basic physiological principle in healthy women, demonstrating different movement patterns of diaphragm, pelvic floor, and muscular wall surrounding the abdominal cavity during a Valsalva maneuver as opposed to a straining maneuver, by means of real-time dynamic magnetic resonance imaging (MRI). The study was performed at Hochzirl Hospital, Austria and Department of Radiology, Medical University Innsbruck, Austria. Four healthy women underwent MRI measurements in a 1.5-T whole body MR-scanner. Coronal, sagittal, and axial slices were acquired simultaneously and a dynamic MRI sequence was used to assess cranio-caudal movements of the diaphragm and pelvic floor and of concomitant changes in anterolateral abdominal muscle thickness and abdominal diameter at the umbilical level. Both the Valsalva maneuver and the straining maneuver began with deep inspiration and downward movement of the diaphragm. During the exertion phase of both maneuvers, abdominal muscle thickness increased and abdominal diameter decreased. During the Valsalva maneuver, the pelvic floor moved cranially parallel to the diaphragm, whereas during the straining maneuver, the pelvic floor was markedly displaced caudally. The Valsalva maneuver reflects an expiratory pattern with diaphragm and pelvic floor elevation, whereas during straining the pelvic floor descends. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  5. Importance of adequately performed Valsalva maneuver to detect patent foramen ovale during transesophageal echocardiography.

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    Rodrigues, Ana Clara; Picard, Michael H; Carbone, Aime; Arruda, Ana Lúcia; Flores, Thaís; Klohn, Juliana; Furtado, Meive; Lira-Filho, Edgar B; Cerri, Giovanni G; Andrade, José L

    2013-11-01

    Transesophageal echocardiography (TEE) plays an important role in evaluating cardioembolic sources of emboli. The identification of a patent foramen ovale (PFO) is reportedly improved with TEE compared with transthoracic echocardiography (TTE), but the Valsalva maneuver during TEE may be difficult or suboptimal. The aim of this study was to assess the efficacy of the Valsalva maneuver for PFO diagnosis using TEE compared with TTE by evaluating patients with ischemic stroke referred for echocardiography. Only patients able to perform the Valsalva maneuver during TTE were included; efficacy was defined by a 20 cm/sec decrease in transmitral E velocity. A PFO was judged present when microbubbles of agitated intravenous saline were seen in the left chambers within three cycles after right atrial opacification. Of 108 patients (mean age, 55 ± 15 years; 61 men), 48 (44%) were judged to have PFOs by TEE and/or TTE. In 36 patients (33% of the total, 75% of those with PFOs), microbubbles were observed both by TEE and TTE, in seven patients only during TTE, and in five patients only during TEE. In patients able to satisfactorily perform the Valsalva maneuver during TEE, 22 PFOs were found, and two shunts (9%) were missed, whereas in patients unable to perform this maneuver, 26 PFOs were observed, with five shunts missed (19%) (P TTE, either the echocardiographic window was suboptimal or the shunt was small. An adequate Valsalva maneuver is crucial for diagnosis of PFO; most patients with stroke may be screened using TTE with contrast and the Valsalva maneuver, with TEE indicated in case of suboptimal transthoracic images. Copyright © 2013 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.

  6. Differences in muscle activation patterns during pelvic floor muscle contraction and Valsalva maneuver.

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    Thompson, Judith A; O'Sullivan, Peter B; Briffa, N Kathryn; Neumann, Patricia

    2006-01-01

    To investigate the different muscle activation patterns around the abdomino-pelvic cavity in continent women and their effect on pressure generation during a correct pelvic floor muscle (PFM) contraction and a Valsalva maneuver. Thirteen continent women were assessed. Abdominal, chest wall, and PFM activity and vaginal and intra-abdominal pressure (IAP), were recorded during two tasks: PFM contraction and Valsalva whilst bladder base position was monitored on trans-abdominal ultrasound. A correct PFM contraction was defined as one that resulted in bladder base elevation and a Valsalva resulted in bladder base depression. Comparison of the mean of the normalized EMG activity of all the individual muscle groups was significantly different between PFM contraction and Valsalva (P = 0.04). During a correct PFM contraction, the PFM were more active than during Valsalva (P = 0.001). During Valsalva, all the abdominal muscles (IO (P = 0.006), EO (P < 0.001), RA (P = 0.011)), and the chest wall (P < 0.001) were more active than during PFM contraction. The change in IAP was greater during Valsalva (P = 0.001) but there was no difference in the change in vaginal pressure between PFM contraction and Valsalva (P = 0.971). This study demonstrates a difference in muscle activation patterns between a correct PFM contraction and Valsalva maneuver. It is important to include assessment of the abdominal wall, chest wall, and respiration in the clinical evaluation of women performing PFM exercises as abdominal wall bracing combined with an increase in chest wall activity may cause rises in IAP and PFM descent. (c) 2005 Wiley-Liss, Inc.

  7. Heart rate changes during the Valsalva maneuver in patients with isolated aortic insufficiency

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    Navarro A.E.

    1997-01-01

    Full Text Available To determine the possible relationship between left ventricular dilatation and heart rate changes provoked by the Valsalva maneuver (Valsalva ratio, we studied 9 patients with isolated chronic aortic insufficiency. Left ventricular systolic function was assessed by two-dimensional echocardiography and cardiac catheterization. All patients were asymptomatic (functional class I of the New York Heart Association. The left ventricular internal diameters and volumes were significantly increased in all patients. The asymptomatic patients had either normal or slightly depressed ejection fraction (EF>0.40. The Valsalva ratio of these asymptomatic patients showed no significant correlation with the left ventricular volumes or with the left ventricular ejection fraction. In other words, parasympathetic heart rate control, as expressed by the Valsalva ratio, was normal in the asymptomatic patients with left ventricular dilatation and preserved left ventricular ejection fraction. Therefore, left ventricular dilatation may not be the major mechanism responsible for the abnormal parasympathetic heart rate control of patients with acquired heart disease

  8. Middle cerebral artery blood velocity during intense static exercise is dominated by a Valsalva maneuver

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    Pott, Frank; van Lieshout, Johannes J.; Ide, Kojiro; Madsen, Per; Secher, Niels H.

    2003-01-01

    Lifting of a heavy weight may lead to "blackout" and occasionally also to cerebral hemorrhage, indicating pronounced consequences for the blood flow through the brain. We hypothesized that especially strenuous respiratory straining (a Valsalva-like maneuver) associated with intense static exercise

  9. Doppler ultrasonography measuement of hepatic hemodynamics during Valsalva maneuver: healthy volunteers study

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    Bang, Dong Ho; Son, Young Jin; Lee, Young Hwan; Yoon, Kwon Ha [Dept. of Radiology, Wonkwang University School of Medicine, Iksan (Korea, Republic of)

    2015-01-15

    The aim of our study was to assess the hemodynamic change of liver during the Valsalva maneuver using Doppler ultrasonography. Thirty healthy men volunteers were enrolled (mean age, 25.5±3.64 years). The diameter, minimal and maximal velocities, and volume flow of intrahepatic inferior vena cava (IVC), middle hepatic vein (MHV), and right main portal vein (RMPV) was measured during both rest and Valsalva maneuver. These changes were compared using paired t-test. The mean diameters (cm) of the intrahepatic IVC at rest and Valsalva maneuver were 1.94±0.40 versus 0.56±0.66 (P<0.001). The mean diameter (cm), minimal velocity (cm/sec), maximal velocity (cm/sec), and volume flow (mL/min) of MHV at rest and Valsalva maneuver were 0.60±0.15 versus 0.38±0.20 (P<0.001), -7.98±5.47 versus 25.74±13.13 (P<0.001), 21.34±6.89 versus 35.12±19.95 (P=0.002), and 106.94±97.65 versus 153.90±151.80 (P=0.014), respectively. Those of RMPV at rest and Valsalva maneuver were 0.78±0.21 versus 0.76±0.20 (P=0.485), 20.21±8.22 versus 18.73±7.43 (P=0.351), 26.79±8.85 versus 24.93±9.91 (P=0.275), and 391.52±265.63 versus 378.43±239.36 (P=0.315), respectively. The blood flow velocity and volume flow of MHV increased significantly during Valsalva maneuver. These findings suggest that hepatic vein might play an important role to maintain venous return to the heart during the maneuver.

  10. Hemodynamic responses during and after multiple sets of stretching exercises performed with and without the Valsalva maneuver

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    Tainah P. Lima

    2015-05-01

    Full Text Available OBJECTIVE: This study investigated the acute hemodynamic responses to multiple sets of passive stretching exercises performed with and without the Valsalva maneuver. METHODS: Fifteen healthy men aged 21 to 29 years with poor flexibility performed stretching protocols comprising 10 sets of maximal passive unilateral hip flexion, sustained for 30 seconds with equal intervals between sets. Protocols without and with the Valsalva maneuver were applied in a random counterbalanced order, separated by 48-hour intervals. Hemodynamic responses were measured by photoplethysmography pre-exercise, during the stretching sets, and post-exercise. RESULTS: The effects of stretching sets on systolic and diastolic blood pressure were cumulative until the fourth set in protocols performed with and without the Valsalva maneuver. The heart rate and rate pressure product increased in both protocols, but no additive effect was observed due to the number of sets. Hemodynamic responses were always higher when stretching was performed with the Valsalva maneuver, causing an additional elevation in the rate pressure product. CONCLUSIONS: Multiple sets of unilateral hip flexion stretching significantly increased blood pressure, heart rate, and rate pressure product values. A cumulative effect of the number of sets occurred only for systolic and diastolic blood pressure, at least in the initial sets of the stretching protocols. The performance of the Valsalva maneuver intensified all hemodynamic responses, which resulted in significant increases in cardiac work during stretching exercises.

  11. Hemodynamic responses during and after multiple sets of stretching exercises performed with and without the Valsalva maneuver.

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    Lima, Tainah P; Farinatti, Paulo T V; Rubini, Ercole C; Silva, Elirez B; Monteiro, Walace D

    2015-05-01

    This study investigated the acute hemodynamic responses to multiple sets of passive stretching exercises performed with and without the Valsalva maneuver. Fifteen healthy men aged 21 to 29 years with poor flexibility performed stretching protocols comprising 10 sets of maximal passive unilateral hip flexion, sustained for 30 seconds with equal intervals between sets. Protocols without and with the Valsalva maneuver were applied in a random counterbalanced order, separated by 48-hour intervals. Hemodynamic responses were measured by photoplethysmography pre-exercise, during the stretching sets, and post-exercise. The effects of stretching sets on systolic and diastolic blood pressure were cumulative until the fourth set in protocols performed with and without the Valsalva maneuver. The heart rate and rate pressure product increased in both protocols, but no additive effect was observed due to the number of sets. Hemodynamic responses were always higher when stretching was performed with the Valsalva maneuver, causing an additional elevation in the rate pressure product. Multiple sets of unilateral hip flexion stretching significantly increased blood pressure, heart rate, and rate pressure product values. A cumulative effect of the number of sets occurred only for systolic and diastolic blood pressure, at least in the initial sets of the stretching protocols. The performance of the Valsalva maneuver intensified all hemodynamic responses, which resulted in significant increases in cardiac work during stretching exercises.

  12. Effects of repeated Valsalva maneuver straining on cardiac and vasoconstrictive baroreflex responses

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    Convertino, Victor A.; Ratliff, Duane A.; Doerr, Donald F.; Ludwig, David A.; Muniz, Gary W.; Benedetti, Erik; Chavarria, Jose; Koreen, Susan; Nguyen, Claude; Wang, Jeff

    2003-01-01

    INTRODUCTION: We hypothesized that repeated respiratory straining maneuvers (repeated SM) designed to elevate arterial BPs (arterial baroreceptor loading) would acutely increase baroreflex responses. METHODS: We tested this hypothesis by measuring cardiac baroreflex responses to carotid baroreceptor stimulation (neck pressures), and changes in heart rate and diastolic BP after reductions in BP induced by a 15-s Valsalva maneuver in 10 female and 10 male subjects at 1, 3, 6, and 24 h after performing repeated SM. Baroreflex responses were also measured in each subject at 1, 3, 6, and 24 h at the same time on a separate day without repeated SM (control) in a randomized, counter-balanced cross-over experimental design. RESULTS: There was no statistical difference in carotid-cardiac and peripheral vascular baroreflex responses measured across time following repeated SM compared with the control condition. Integrated cardiac baroreflex response (deltaHR/ deltaSBP) measured during performance of a Valsalva maneuver was increased by approximately 50% to 1.1 +/- 0.2 bpm x mm Hg(-1) at 1 h and 1.0 +/- 0.1 bpm x mm Hg(-1) at 3 h following repeated SM compared with the control condition (0.7 +/- 0.1 bpm x mm Hg(-1) at both 1 and 3 h, respectively). However, integrated cardiac baroreflex response after repeated SM returned to control levels at 6 and 24 h after training. These responses did not differ between men and women. CONCLUSIONS: Our results are consistent with the notion that arterial baroreceptor loading induced by repeated SM increased aortic, but not carotid, cardiac baroreflex responses for as long as 3 h after repeated SM. We conclude that repeated SM increases cardiac baroreflex responsiveness which may provide patients, astronauts, and high-performance aircraft pilots with protection from development of orthostatic hypotension.

  13. Proposal Intensity Adequacy of Expiratory Effort and Heart Rate Behavior During the Valsalva Maneuver in Preadolescents

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    Mario Augusto Paschoal

    2014-08-01

    Full Text Available Background: When performing the Valsalva maneuver (VM, adults and preadolescents produce the same expiratory resistance values. Objective: To analyze heart rate (HR in preadolescents performing VM, and propose a new method for selecting expiratory resistance. Method: The maximal expiratory pressure (MEP was measured in 45 sedentary children aged 9-12 years who subsequently performed VM for 20 s using an expiratory pressure of 60%, 70%, or 80% of MEP. HR was measured before, during, and after VM. These procedures were repeated 30 days later, and the data collected in the sessions (E1, E2 were analyzed and compared in periods before, during (0-10 and 10-20 s, and after VM using nonparametric tests. Results: All 45 participants adequately performed VM in E1 and E2 at 60% of MEP. However, only 38 (84.4% and 25 (55.5% of the participants performed the maneuver at 70% and 80% of MEP, respectively. The HR delta measured during 0-10 s and 10-20 s significantly increased as the expiratory effort increased, indicating an effective cardiac autonomic response during VM. However, our findings suggest the VM should not be performed at these intensities. Conclusion: HR increased with all effort intensities tested during VM. However, 60% of MEP was the only level of expiratory resistance that all participants could use to perform VM. Therefore, 60% of MEP may be the optimal expiratory resistance that should be used in clinical practice.

  14. A Comparison of Vaginal Pressures and Abdominal Muscle Thickness According to Childbirth Delivery Method during the Valsalva Maneuver

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    Kim, Haroo; Kak, Hwang-Bo; Kim, Boin

    2014-01-01

    [Purpose] The purpose of this study was to compare the effect of childbirth delivery method on vaginal pressure and abdominal thickness during the Valsalva maneuver (VAL). [Subjects] Thirty healthy female volunteers (26–39 years of age) were selected for this research. Their delivery histories were: nulliparous 10, vaginal delivery 10, and Cesarean delivery 10. None of the participants had a history of incontinence. [Methods] In the crook-lying position, a perineometer probe was inserted into...

  15. The Effect of Valsalva Maneuver and Short Isometric Contraction on Autonomic Functions and Coronary Flow in Patients with Severe Heart Failure

    Czech Academy of Sciences Publication Activity Database

    Fráňa, P.; Kára, T.; Souček, M.; Jurák, Pavel; Halámek, Josef; Sitar, J.; Groch, L.; Řiháček, I.; Bartosikova, L.; Fráňová, J.

    2004-01-01

    Roč. 22, Suppl.1 (2004), s. 92 ISSN 0263-6352. [Scientific meeting of the international society of hypertension /20./. 15.02.2004-19.02.2004, Sao Paulo] Institutional research plan: CEZ:AV0Z2065902 Keywords : Valsalva maneuver * heart failure * short isometric contraction Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  16. Spontaneous Pushing in Lateral Position versus Valsalva Maneuver During Second Stage of Labor on Maternal and Fetal Outcomes: A Randomized Clinical Trial.

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    Vaziri, Farideh; Arzhe, Amene; Asadi, Nasrin; Pourahmad, Saeedeh; Moshfeghy, Zeinab

    2016-10-01

    There are concerns about the harmful effects of the Valsalva maneuver during the second stage of labor. Comparing the effects of spontaneous pushing in the lateral position with the Valsalva maneuver during the second stage of labor on maternal and fetal outcomes. Inclusion criteria in this randomized clinical trial conducted in Iran were as follows: nulliparous mothers, live fetus with vertex presentation, gestational age of 37 - 40 weeks, spontaneous labor, and no complications. The intervention group pushed spontaneously while they were in the lateral position, whereas the control group pushed using Valsalva method while in the supine position at the onset of the second stage of labor. Maternal outcomes such as pain and fatigue severity and fetal outcomes such as pH and pO2 of the umbilical cord blood were measured. Data pertaining to 69 patients, divided into the intervention group (35 subjects) and control group (34 subjects), were analyzed statistically. The mean pain (7.80 ± 1.21 versus 9.05 ± 1.11) and fatigue scores (46.59 ± 21 versus 123.36 ± 43.20) of the two groups showed a statistically significant difference (P umbilical cord blood pO 2 levels of both groups showed a statistically significant difference (28.29 ± 11.76 versus 18.83 ± 9.86, P pain severity of the mothers. Also, it did not worsen fetal outcomes. Thus, it can be used as an alternative method for the Valsalva maneuver.

  17. Dynamic changes in optic disc morphology, choroidal thickness, anterior chamber parameters, and intraocular pressure during Valsalva maneuver

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    Alper Mete

    Full Text Available ABSTRACT Purpose: To investigate the effects of the Valsalva maneuver (VM on optic disc morphology, choroidal thickness, and anterior chamber parameters. Methods: This prospective observational study included 60 eyes of 60 healthy subjects. The anterior chamber parameters, including central corneal thickness (CCT, anterior chamber depth (ACD, anterior chamber angle (ACA, anterior chamber volume (ACV, pupil diameter (PD, axial length (AL, subfoveal and peripapillary choroidal thickness, optic disc parameters, and intraocular pressure (IOP, were measured at rest and during VM. Results: VM did not have any significant influence on AL, subfoveal and peripapillary choroidal thickness, optic disc area, rim area, cup area, cup-to-disc area ratio, vertical cup-to-disc ratio, rim volume, cup volume, and nerve head volume measurements (for all; p >0.05. IOP and PD significantly increased during VM (for both; p <0.001. VM significantly decreased CCT, ACD, ACA, and ACV values (for all; p <0.001. Moreover, the optic nerve cup volume decreased and the horizontal cup-to-disc ratio significantly increased during VM (for both; p <0.05. Conclusions: VM may cause transient changes in IOP, optic disc morphology, and anterior chamber parameters.

  18. Venous leakage treatment revisited: pelvic venoablation using aethoxysclerol under air block technique and Valsalva maneuver

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    Ralf Herwig

    2015-03-01

    Full Text Available Objective: We evaluated the effectiveness of pelvic vein embolization with aethoxysclerol in aero-block technique for the treatment of impotence due to venous leakage in men using sildenafil for intercourse. The aim of the procedure was to reduce the use of sildenafil. Methods: A total of 96 patients with veno-occlusive dysfunction, severe enough for the need of PDE5 inhibitors for vaginal penetration, underwent pelvic venoablation with aethoxysclerol. The mean patient age was 53.5 years. Venous leaks were identified by Color Doppler Ultrasound after intracavernous alprostadil injection. Under local anesthesia a 20-gauge needle was inserted into the deep dorsal penile vein. The pelvic venogram was obtained through deep dorsal venography. Aethoxysclerol 3% as sclerosing agent was injected after air-block under Valsalva manoeuver. Success was defined as the ability to achieve vaginal insertion without the aid of any drugs, vasoactive injections, penile prosthesis, or vacuum device. Additionally, a pre- and post- therapy IIEF score and a digital overnight spontaneous erections protocol (OSEP with the NEVA™-system was performed. Results: At 3 month follow-up 77 out of 96 patients (80.21% reported to have erections sufficient for vaginal insertion without the use of any drug or additional device. Four (4.17% patients did not report any improvement. Follow up with color Doppler ultrasound revealed a new or persistent venous leakage in 8 (8.33% of the patients. No serious complications occurred. Conclusions: Our new pelvic venoablation technique using aethoxysclerol in air-block technique was effective, minimally invasive, and cost-effective. All patients were able to perform sexual intercourse without the previously used dosage of PDE5 inhibitor. This new method may help in patients with contra-indications against PDE5 inhibitors, in patients who cannot afford the frequent usage of expensive oral medication or those who do not fully respond to PDE5

  19. The repeated sit-to-stand maneuver is a superior method for cardiac baroreflex assessment: a comparison with the modified Oxford method and Valsalva maneuver.

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    Horsman, H M; Tzeng, Y C; Galletly, D C; Peebles, K C

    2014-12-01

    Baroreflex assessment has diagnostic and prognostic utility in the clinical and research environments, and there is a need for a reliable, simple, noninvasive method of assessment. The repeated sit-to-stand method induces oscillatory changes in blood pressure (BP) at a desired frequency and is suitable for assessing dynamic baroreflex sensitivity (BRS). However, little is known about the reliability of this method and its ability to discern fundamental properties of the baroreflex. In this study we sought to: 1) evaluate the reliability of the sit-to-stand method for assessing BRS and compare its performance against two established methods (Oxford method and Valsalva maneuver), and 2) examine whether the frequency of the sit-to-stand method influences hysteresis. Sixteen healthy participants underwent three trials of each method. For the sit-to-stand method, which was performed at 0.1 and 0.05 Hz, BRS was quantified as an integrated response (BRSINT) and in response to falling and rising BP (BRSDOWN and BRSUP, respectively). Test retest reliability was assessed using the intraclass correlation coefficient (ICC). Irrespective of frequency, the ICC for BRSINT during the sit-to-stand method was ≥0.88. The ICC for a rising BP evoked by phenylephrine (PEGAIN) in the Oxford method was 0.78 and ≤0.5 for the remaining measures. During the sit-to-stand method, hysteresis was apparent in all participants at 0.1 Hz but was absent at 0.05 Hz. These findings indicate the sit-to-stand method is a statistically reliable BRS assessment tool and suitable for the examination of baroreflex hysteresis. Using this approach we showed that baroreflex hysteresis is a frequency-dependent phenomenon. Copyright © 2014 the American Physiological Society.

  20. Cardiovascular responses to passive static flexibility exercises are influenced by the stretched muscle mass and the Valsalva maneuver.

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    Farinatti, Paulo T V; Soares, Pedro P S; Monteiro, Walace D; Duarte, Antonio F A; Castro, Luis A Viveiros de

    2011-01-01

    The respiratory pattern is often modified or even blocked during flexibility exercises, but little is known about the cardiovascular response to concomitant stretching and the Valsalva maneuver (VM) in healthy subjects. This study evaluated the heart rate (HR), systolic blood pressure (SBP), and rate-pressure product (RPP) during and after large and small muscle group flexibility exercises performed simultaneously with the VM. Asymptomatic volunteers (N = 22) with the following characteristics were recruited: age, 22 ± 3 years; weight, 73 ± 6 kg; height, 175 ± 5 cm; HR at rest, 66 ± 9 BPM; and SBP at rest, 113 ± 10 mmHg. They performed two exercises: four sets of passive static stretching for 30 s of the dorsi-flexion (DF) of the gastrocnemius and the hip flexion (HF) of the ischio-tibialis. The exercises were performed with (V+) or without (V-) the VM in a counterbalanced order. The SBP and HR were measured, and the RPP was calculated before the exercise session, at the end of each set, and during a 30-min post-exercise recovery period. The within-group comparisons showed that only the SBP and RPP increased throughout the sets (p < 0.05), but no post-exercise hypotension was detected. The between-group comparisons showed that greater SBP increases were related to the VM and to a larger stretched muscle mass. Differences for a given set were identified for the HR (the HFV+ and HFV- values were higher than the DFV+ and DFV- values by approximately 12 BPM), SBP (the HFV+ value was higher than the DFV+ and DFV- values by approximately 12 to 15 mmHg), and RPP (the HFV+ value was higher than the HFV- value by approximately 2000 mmHGxBPM, and the HFV+ value was higher than the DFV+ and DFV- values by approximately 4000 mmHGxBPM). Both the stretched muscle mass and the VM influence acute cardiovascular responses to multiple-set passive stretching exercise sessions.

  1. Cardiovascular responses to passive static flexibility exercises are influenced by the stretched muscle mass and the Valsalva maneuver

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    Paulo T. V Farinatti

    2011-01-01

    Full Text Available BACKGROUND: The respiratory pattern is often modified or even blocked during flexibility exercises, but little is known about the cardiovascular response to concomitant stretching and the Valsalva maneuver (VM in healthy subjects. OBJECTIVES: This study evaluated the heart rate (HR, systolic blood pressure (SBP, and rate-pressure product (RPP during and after large and small muscle group flexibility exercises performed simultaneously with the VM. METHODS: Asymptomatic volunteers (N = 22 with the following characteristics were recruited: age, 22 ± 3 years; weight, 73 ± 6 kg; height, 175 ± 5 cm; HR at rest, 66 ± 9 BPM; and SBP at rest, 113 ± 10 mmHg. They performed two exercises: four sets of passive static stretching for 30 s of the dorsi-flexion (DF of the gastrocnemius and the hip flexion (HF of the ischio-tibialis. The exercises were performed with (V+ or without (V- the VM in a counterbalanced order. The SBP and HR were measured, and the RPP was calculated before the exercise session, at the end of each set, and during a 30-min post-exercise recovery period. RESULTS: The within-group comparisons showed that only the SBP and RPP increased throughout the sets (p<0.05, but no post-exercise hypotension was detected. The between-group comparisons showed that greater SBP increases were related to the VM and to a larger stretched muscle mass. Differences for a given set were identified for the HR (the HFV+ and HFV- values were higher than the DFV+ and DFV- values by approximately 12 BPM, SBP (the HFV+ value was higher than the DFV+ and DFV- values by approximately 12 to 15 mmHg, and RPP (the HFV+ value was higher than the HFV- value by approximately 2000 mmHGxBPM, and the HFV+ value was higher than the DFV+ and DFV- values by approximately 4000 mmHGxBPM. CONCLUSION: Both the stretched muscle mass and the VM influence acute cardiovascular responses to multiple-set passive stretching exercise sessions.

  2. Valsalva maneuver unveils central baroreflex dysfunction with altered blood pressure control in persons with a history of mild traumatic brain injury.

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    Hilz, Max J; Liu, Mao; Koehn, Julia; Wang, Ruihao; Ammon, Fabian; Flanagan, Steven R; Hösl, Katharina M

    2016-05-04

    Patients with a history of mild TBI (post-mTBI-patients) have an unexplained increase in long-term mortality which might be related to central autonomic dysregulation (CAD). We investigated whether standardized baroreflex-loading, induced by a Valsalva maneuver (VM), unveils CAD in otherwise healthy post-mTBI-patients. In 29 healthy persons (31.3 ± 12.2 years; 9 women) and 25 post-mTBI-patients (35.0 ± 13.2 years, 7 women, 4-98 months post-injury), we monitored respiration (RESP), RR-intervals (RRI) and systolic blood pressure (BP) at rest and during three VMs. At rest, we calculated parameters of total autonomic modulation [RRI-coefficient-of-variation (CV), RRI-standard-deviation (RRI-SD), RRI-total-powers], of sympathetic [RRI-low-frequency-powers (LF), BP-LF-powers] and parasympathetic modulation [square-root-of-mean-squared-differences-of-successive-RRIs (RMSSD), RRI-high-frequency-powers (HF)], the index of sympatho-vagal balance (RRI LF/HF-ratios), and baroreflex sensitivity (BRS). We calculated Valsalva-ratios (VR) and times from lowest to highest RRIs after strain (VR-time) as indices of parasympathetic activation, intervals from highest systolic BP-values after strain-release to the time when systolic BP had fallen by 90 % of the differences between peak-phase-IV-BP and baseline-BP (90 %-BP-normalization-times), and velocities of BP-normalization (90 %-BP-normalization-velocities) as indices of sympathetic withdrawal. We compared patient- and control-parameters before and during VM (Mann-Whitney-U-tests or t-tests; significance: P baroreflex-loading indicate subtle CAD with altered baroreflex adjustment to challenge. More severe autonomic challenge might trigger more prominent cardiovascular dysregulation and thus contribute to increased mortality risk in post-mTBI-patients.

  3. In a dynamic lifting task, the relationship between cross-sectional abdominal muscle thickness and the corresponding muscle activity is affected by the combined use of a weightlifting belt and the Valsalva maneuver.

    Science.gov (United States)

    Blanchard, Trevor W; Smith, Camille; Grenier, Sylvain G

    2016-06-01

    It has been shown that under isometric conditions, as the activity of the abdominal muscles increases, the thicknesses of the muscles also increase. The purpose of this experiment was to determine whether change in muscle thickness could be used as a measure of muscle activity during a deadlift as well as determining the effect of a weightlifting belt and/or the Valsalva maneuver on the muscle thicknesses. The Transversus Abdominis (TrA) and Internal Obliques (IO) muscles were analyzed at rest and during a deadlift. Muscle thickness was measured using ultrasound imaging and muscle activity was simultaneously recorded using electromyography. Each subject performed deadlift under normal conditions, while performing the Valsalva maneuver, while wearing a weightlifting belt and while both utilizing the belt and the Valsalva maneuver. There was no relationship between change in muscle thickness and muscle activity for both the TrA and IO (R(2)abdominal muscle thickness whereas the belt limited muscle expansion; each with an increase in activity. These results indicate that ultrasound cannot be used to measure muscle activity for a deadlift and that the belt affects how the IO and TrA function together. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Synergistic effect of energy drinks and overweight/obesity on cardiac autonomic testing using the Valsalva maneuver in university students.

    Science.gov (United States)

    Majeed, Farrukh; Yar, Talay; Alsunni, Ahmed; Alhawaj, Ali Fouad; AlRahim, Ahmed; Alzaki, Muneer

    2017-01-01

    Obesity and caffeine consumption may lead to autonomic disturbances that can result in a wide range of cardiovascular disorders. To determine autonomic disturbances produced by the synergistic effects of overweight or obesity (OW/OB) and energy drinks. Cross-sectional, analytical. Physiology department at a university in Saudi Arabia. University students, 18-22 years of age, of normal weight (NW) and OW/OB were recruited by convenience sampling. Autonomic testing by the Valsalva ratio (VR) along with systolic and diastolic blood pressure, pulse pressure, and mean arterial blood pressure were measured at baseline (0 minute) and 60 minutes after energy drink consumption. Autonomic disturbance, hemodynamic changes. In 50 (27 males and 23 females) subjects, 21 NW and 29 OW/OB, a significant decrease in VR was observed in OW/OB subjects and in NW and OW/OB females at 60 minutes after energy drink consumption. Values of systolic and diastolic blood pressure, pulse pressure and mean arterial blood pressure were also significantly higher in OW/OB and in females as compared to NW and males. BMI was negatively correlated with VR and diastolic blood pressure at 60 minutes. Obesity and energy drinks alter autonomic functions. In some individuals, OW/OB may augment these effects. Due to time and resource restraints, only the acute effects of energy drinks were examined.

  5. A Comparison of Transthroracic Echocardiograpy and Transcranial Doppler With Contrast Agent for Detection of Patent Foramen Ovale With or Without the Valsalva Maneuver

    Science.gov (United States)

    Zhao, Enfa; Wei, Yajuan; Zhang, Yafei; Zhai, Nina; Zhao, Ping; Liu, Baomin

    2015-01-01

    Abstract Patent foramen ovale (PFO) is a remnant of the fetal circulation exist in 20% of the general population. The purpose of our study was to compare of transthoracic echocardiography (TTE) and contrast-transcranial Doppler sonography (c-TCD) in the diagnosis and quantification of PFO with or without the Valsalva maneuver (VM). We studied 106 patients with a high clinical suspicion for PFO prospectively. Simultaneous c-TCD and TTE were conducted using agitated saline solution to detect right to left shunt (RLS). To classify RLS, mainly PFO, we applied a 4-level visual classification for c-TCD test: no occurrence of micro-embolic signals; grade I, 1 to 10 signals; grade II, 10 to 30 signals but not curtain; and grade III, curtain pattern. We used the number of micro-bubbles appeared in left atrium per frame image to define classification for TTE test: no occurrence of micro-bubbles; grade I, 1 to 10 micro-bubbles; grade II, 10 to 30 micro-bubbles; and grade III, more than 30 micro-bubbles or left atrium nearly filled with micro-bubbles or left atrial opacity. Statistical analyses were performed using SPSS Version 18.0. RLS was detected in 36.0% in c-TCD test and in 46% in TTE test at rest (P = 0.158). And during the VM, RLS was detected in 99.0% in c-TCD test and in 83.0% in TTE test (P TTE at rest, the positive results of them with VM is more higher, respectively (all P TTE should used as initial screening tool for PFO. VM increases the size of shunt. VM resulted in detection of more RLS both in c-TCD and TTE tests. PMID:26512622

  6. Avaliação da frequência cardíaca à medida de pressão expiratória máxima estática e à manobra de Valsalva em jovens saudáveis Heart rate assessment during maximal static expiratory pressure and Valsalva maneuver in healthy young men

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    Vinicius Minatel

    2012-10-01

    Full Text Available CONTEXTUALIZAÇÃO: A medida de pressão expiratória máxima (PEmáx possui algumas contraindicações, pois acredita-se que as respostas obtidas nessa medida são similares às respostas encontradas na manobra de Valsalva (MV. OBJETIVOS: O objetivo principal é avaliar a resposta da frequência cardíaca (FC durante a medida da PEmáx e da MV em jovens saudáveis, em diferentes posturas, para identificar se e em qual condição a PEmáx reproduz as respostas obtidas na MV e, adicionalmente, estimar o trabalho realizado nas manobras. MÉTODO: Doze jovens saudáveis foram avaliados, orientados e familiarizados com as manobras. A MV foi composta por um esforço expiratório (40 mmHg durante 15 segundos contra um manômetro. A PEmáx foi executada segundo a American Thoracic Society. Ambas as medidas foram realizadas nas posturas supino e sentado. Para a análise da variação da frequência cardíaca (∆FC, índice de Valsalva (IV, índice da PEmáx (IPEmáx e o trabalho estimado das manobras (Wtotal, Wisotime, Wtotal/∆FCtotal e Wisotime/∆FCisotime , utilizou-se ANOVA two-way com post-hoc de Holm-Sidak (pBACKGROUND: The measure of the maximal expiratory pressure (MEP has some contraindications, as it is believed that the responses obtained in this measure are similar to the Valsalva maneuver (VM. OBJECTIVE: The main purpose of this study was to evaluate the heart rate responses (HR during the MEP and the VM measures in healthy young men into different postures aiming to identify whether and in which situation the MEP reproduces the responses obtained in the VM. Additionally we aim to estimate the workload realized during the maneuvers. METHOD: Twelve healthy young men were evaluated, instructed and familiarized with the maneuvers. The VM was characterized by an expiratory effort (40 mmHg against a manometer for 15 seconds. The MEP measure has been performed according to the American Thoracic Society. Both measures were performed at sitting

  7. Pressão expiratória positiva nas vias aéreas não reproduz as respostas de frequência cardíaca à manobra de Valsalva em homens jovens saudáveis Expiratory positive airway pressure does not reproduce heart rate responses to Valsalva maneuver in healthy young men

    Directory of Open Access Journals (Sweden)

    Isabella Gracindo Pissinato

    2012-06-01

    Full Text Available A pressão expiratória positiva nas vias aéreas (EPAP é um recurso terapêutico que compreende uma inspiração seguida de expiração contra resistência. Sua aplicação promove ajustes no sistema cardiovascular, de maneira similar ao observado durante a manobra de Valsalva (MV. O objetivo deste estudo foi analisar a resposta da frequência cardíaca (FC à MV e às diferentes formas de aplicação de EPAP a fim de identificar se e em qual condição esta técnica reproduz a resposta da FC observada na MV, em homens jovens aparentemente saudáveis. Foram estudados 10 sujeitos (24±3 anos; 25±3 kg/m² que realizaram os procedimentos de MV e EPAP, aleatoriamente em dias diferentes. Na MV o esforço expiratório foi sustentado por 15 s (pressão oral de 40 mmHg [53,4 cmH2O]. Empregou-se duas técnicas de EPAP (isolada e terapêutica contra 3 níveis de pressão (10, 15 e 20 cmH2O, aplicados aleatoriamente. As manobras foram repetidas três vezes com intervalo de cinco minutos. Considerou-se o maior valor de variação da FC (DFC de cada manobra para análise. Empregou-se o teste Shapiro-Wilk para verificar a distribuição dos dados e ANOVA para medidas repetidas, com post-hoc de Fisher, considerando-se αThe expiratory positive airway pressure (EPAP is a therapeutic resource that comprises an inspiration followed by expiration against resistance. During its application there were adjustments in the cardiovascular system, similar to those observed during the Valsalva maneuver (VM. The aim of this study was to analyze the heart rate (HR response to VM and to different ways of EPAP application to identify if and in which condition this technique reproduces the HR response observed in the VM, in apparently healthy young men. Ten subjects (24±3 years, 25±3 kg/m² performed randomly the VM and EPAP procedures on different days. The expiratory effort in VM was sustained for 15 s (oral pressure of 40 mmHg [53.4cm H2O]. Two EPAP techniques were

  8. Valsalva maneuver procedures in the diagnosis of right-to-left shunt by contrast-enhanced transcranial doppler using agitated saline solution with blood as a contrast agent Manobra de Valsalva no diagnóstico de embolia paradoxal pelo doppler transcraniano contrastado com o uso de solução salina agitada associada a sangue como meio de contraste

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    Marcos Christiano Lange

    2010-06-01

    Full Text Available OBJECTIVE: To compare two different timings for the performance of the Valsalva maneuver (VM using an infusion of agitated saline solution with blood as contrast agent (CA to right-to-left shunt (RLS screening. METHOD: 42 patients were submitted to a standardized contrast-enhanced transcranial doppler (cTCD to screen for right-to-left shunt (RLS. cTCD technique was done with two different moments of the VM: [1] the CA injection during the VM (CAduringVM test; [2] the CA injection before the VM (CApreVM test. RESULTS: Positive MCA tests were observed in 47 (56% CAduringVM tests and in 50 (59.5% CApreVM tests, p=0.64. There was an almost perfect agreement for the positive tests between the CAduringVM and CApreVM test, r s=0.829 (95% CI 0.61-1.00, pOBJETIVO: Comparar dois momentos diferentes da manobra de Valsalva (MV com o uso de solução salina com sangue como meio de contraste (MC para investigação de embolia paradoxal (EP. MÉTODO: 42 pacientes foram submetidos a protocolo padronizado de DTCc com a MV em dois momentos diferentes: [1] injeção do MC durante a MV (teste ACduranteMV; [2] injeção de MC antes da MV (teste ACpreMV. RESULTADOS: Exames positivos foram observados em 47 (56% ACMs testes ACduranteMV e 50 (59.5% testes ACpreMV, p=0.64. Houve uma correlação quase perfeita entre ambos os testes, r s=0.829 (95% CI 0.61-1.00, p<0.001. CONCLUSÃO: O presente estudo demonstra que não existe diferença significativa na positividade de EP pelo DTCc quando são comparados dois momentos diferentes da MV.

  9. Comparison of force exerted on the sternum during a sneeze versus during low-, moderate-, and high-intensity bench press resistance exercise with and without the valsalva maneuver in healthy volunteers.

    Science.gov (United States)

    Adams, Jenny; Schmid, Jack; Parker, Robert D; Coast, J Richard; Cheng, Dunlei; Killian, Aaron D; McCray, Stephanie; Strauss, Danielle; McLeroy Dejong, Sandra; Berbarie, Rafic

    2014-03-15

    Sternal precautions are intended to prevent complications after median sternotomy, but little data exist to support the consensus recommendations. To better characterize the forces on the sternum that can occur during everyday events, we conducted a prospective nonrandomized study of 41 healthy volunteers that evaluated the force exerted during bench press resistance exercise and while sneezing. A balloon-tipped esophageal catheter, inserted through the subject's nose and advanced into the thoracic cavity, was used to measure the intrathoracic pressure differential during the study activities. After the 1 repetition maximum (1-RM) was assessed, the subject performed the bench press at the following intensities, first with controlled breathing and then with the Valsalva maneuver: 40% of 1-RM (low), 70% of 1-RM (moderate), and 1-RM (high). Next, various nasal irritants were used to induce a sneeze. The forces on the sternum were calculated according to a cylindrical model, and a 2-tailed paired t test was used to compare the mean force exerted during a sneeze with the mean force exerted during each of the 6 bench press exercises. No statistically significant difference was found between the mean force from a sneeze (41.0 kg) and the mean total force exerted during moderate-intensity bench press exercise with breathing (41.4 kg). In conclusion, current guidelines and recommendations limit patient activity after a median sternotomy. Because these patients can repeatedly withstand a sneeze, our study indicates that they can withstand the forces from more strenuous activities than are currently allowed. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Contrast transcranial Doppler ultrasound in the detection of right-to-left shunts: comparison of Echovist-200 and Echovist-300, timing of the Valsalva maneuver, and general recommendations for the performance of the test.

    Science.gov (United States)

    Droste, Dirk W; Jekentaite, Ruta; Stypmann, Jörg; Grude, Matthias; Hansberg, Tjark; Ritter, Martin; Nabavi, Darius; Nam, Eun-Mi; Dittrich, Ralf; Wichter, Thomas; Ringelstein, E Bernd

    2002-01-01

    Cardiac right-to-left shunts (RLS) can be identified by transesophageal echocardiography (TEE) as well as by transcranial Doppler ultrasound (TCD) using contrast agents, such as Echovist-200 or Echovist-300 in conjunction with a Valsalva maneuver (VM) as provocation procedure. Both Echovist preparations are in use. Currently, the appropriate timing of the VM is still under debate. Sixty-four patients were investigated by both TEE and bilateral TCD of the middle cerebral arteries. The following protocol was applied in a randomized way: (1) no VM, (2) VM for 5 s starting with the beginning of Echovist-300 injection, (3) VM for 5 s starting 5 s after the beginning of Echovist-300 injection, (4) VM for 5 s starting 10 s after the beginning of Echovist-300 injection, and (5) VM for 5 s starting 5 s after the beginning of Echovist-200 injection. In 27 patients, an RLS was demonstrated by both TEE and contrast TCD (shunt-positive). Twenty-two patients were negative in both investigations, no patient was positive on TEE but negative on TCD, 15 patients were only positive on at least one TCD investigation but negative on TEE. Tests 3 and 5 were the most appropriate ones; test 3 was slightly superior to test 5. TCD using Echovist-300 or Echovist-200 is a sensitive method to identify TEE-proven cardiac RLS. To achieve the best diagnostic accuracy, the VM should be performed for a duration of 5 s starting at 5 s following the beginning of contrast injection. Copyright 2002 S. Karger AG, Basel

  11. The Valsalva maneuver duration during labor expulsive stage: repercussions on the maternal and neonatal birth condition Duração da manobra de Valsalva durante o período expulsivo do parto: repercussões maternas e nas condições neonatais de nascimento

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    Andrea Lemos

    2011-02-01

    Full Text Available OBJECTIVES: This cross-sectional study was designed to examine the effects of the Valsalva Maneuver (VM and its duration on the acid- base equilibrium of the neonate and its maternal repercussions during the expulsive stage of labor, after standard breathing and pushing instructions were given. METHODS: A convenience sample of women with low risk pregnancy (n=33; mean age 22.5±3.7y and gestational age 38.1±1.12wks and their newborns were studied during the expulsive stage of vaginal labor. Coaching consisted of standard recommendations for breathing including prolonged VMs coordinated with pushing. Maternal outcomes included the need for uterus fundal pressure maneuver and episiotomy, perineal trauma and posture. Neonatal outcomes included blood gases sampled from the umbilical cord, and Apgar scores. Data were analyzed with the Fisher's exact test, chi-square test, and Pearson correlation coefficient. RESULTS: None of the maternal outcomes were associated with VM duration. With respect to neonatal outcomes, increased VM duration was associated with reduced venous umbilical pH (r=-0.40; p=0.020, venous base excess (r=-0.42; p=0.014 and with arterial base excess (r=-0.36; p=0.043. Expulsive stage time was negatively associated with umbilical venous and arterial pH. CONCLUSIONS: VM duration during fetal expulsion in labor negatively affects fetal acid-base equilibrium and potentially the wellbeing of the neonate. Our results support the need to consider respiratory strategies during labor, to minimize potential risk to the mother and neonate.OBJETIVOS: O presente estudo de corte transversal teve como objetivo avaliar os efeitos da Manobra de Valsalva (MV e sua duração no equilíbrio ácido-básico fetal e nas repercussões maternas durante o período expulsivo do parto, após instrução respiratória padronizada. MÉTODOS: Uma amostra de conveniência em gestantes de baixo risco (n=33, média de idade 22,5±3.7 anos e idade gestacional 38.1

  12. Revisión sobre la prueba de hiperventilación y la de Valsalva

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    Eduardo Antonio MENA-DOMÍNGUEZ

    2018-01-01

    Full Text Available Introduction and objective: With this paper, we pretend to explain the characteristics and the field of application of two clinical explorations used in the patient with suspected vestibular pathology, the hyperventilation maneuver and the Valsalva maneuver. Methodology: Narrative review. Results: Through different neurophysiological mechanisms, hyperventilation can induce nystagmus in cases of vestibular asymmetry, both peripheral and central. The Valsalva maneuver may also trigger nystagmus and vertigo because of direct transmission of internal ear pressure in cases of perilymphatic fistula, anomalies of the cranio-cervical junction (Arnold-Chiari malformation, and other ossicles, oval window and saccule pathologies. Discussion and conclusions: Both the hyperventilation test and the Valsalva maneuver should be included in the battery of tests for patients with vestibular pathology to, depending on the results obtained, anatomically locate the site of the lesion and justify the use of imaging techniques.

  13. Purtscher-like retinopathy following valsalva maneuver effect: case report

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    Azhany Yaakub

    2011-08-01

    Full Text Available Abstract Introduction Purtscher's retinopathy is a rare condition that is noted in cases related to various types of trauma. The characteristic finding in the fundus is the presence of multiple Purtscher flecken. Purtscher-like retinopathy has a similar presentation in the fundus, but without an association with trauma. Case presentation A 43-year old Malay man presented with a sudden onset of central foggy vision in the left eye after holding his breath for two minutes while catching a falling object. It was not associated with floaters, flashes of light, or head trauma. His vision in the right eye was 6/6, and in his left eye it was finger counting. He had bilateral temporal sub-conjunctival hemorrhages. An examination of his left fundus revealed multiple white cotton wool spots and dot-blot retinal hemorrhages with diffuse retinal edema at the posterior pole. His right fundus was noted to have only mild temporal peri-papillary edema associated with a few dot-blot hemorrhages. Fundus fluorescein angiography showed good arterial perfusion and no evidence of leaking or neo-vascularization. A diagnosis of Purtscher-like retinopathy was made, and the patient was treated with indomethacin tablets for six weeks. At his six-week follow-up examination, his left eye visual acuity had improved to 6/12. His bilateral sub-conjunctival hemorrhage had resolved. His left fundus showed residual multiple cotton wool spots and reduced retinal edema. Conclusions Treatment with non-steroidal anti-inflammatory drugs seems to be effective in reducing edema in patients with Purtscher-like retinopathy.

  14. Powerlifter's purpura: a valsalva-associated phenomenon.

    Science.gov (United States)

    Pierson, Joseph C; Suh, Philip S

    2002-08-01

    The causes of purpura can be classified into intravascular, vascular, and extravascular mechanisms. We describe a case of cervicofacial purpura in a powerlifter attributed to the accompanying Valsalva-associated increased arterial pressure. Powerlifting should be added to the list of activities that may cause purpura.

  15. Epley maneuver

    Science.gov (United States)

    ... repositioning maneuvers; CRP; Benign positional vertigo - Epley; Benign paroxysmal positional vertigo - Epley; BPPV - Epley; BPV - Epley ... Orvidas L, et al. Clinical practice guideline: benign paroxysmal positional vertigo. Otolaryngol: Head Neck Surg . 2008;139(5 Suppl ...

  16. Trans-aortic repair of a sinus of valsalva aneurysm.

    Science.gov (United States)

    Kapetanakis, Emmanouil I; Ieromonachos, Constantinos; Stavridis, George; Antoniou, Theofani A; Athanassopoulos, George; Cokkinos, Dennis V; Alivizatos, Peter A

    2007-01-01

    Sinus of Valsalva aneurysms are rare and vary in their presentation and approach of surgical repair. We report on a case of isolated right sinus of Valsalva aneurysm that underwent successful excision and patch repair with individual sutures placed through the annulus of the aortic valve.

  17. Aneurisma del seno de Valsalva derecho

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    Rebeca Manrique

    2010-10-01

    Full Text Available Varón de 60 años con antecedente de hipertensión arterial, diagnosticado incidentalmente de aneurisma del seno de Valsalva derecho de 7 cm con insuficiencia aórtica ligera. Bajo circulación extracorpórea y pinzamiento aórtico se reseca el aneurisma y se reconstruye el defecto con un parche de prótesis Dacron Hemashield Platinum® (Maquet, Rastatt, Alemania, reimplantando el ostium coronario derecho y realizando derivación aortocoronaria a primera marginal con vena safena (hallazgo en cateterismo preoperatorio. La ecocardiografía intraoperatoria objetivó insuficiencia aórtica trivial residual. Como complicación postoperatoria presentó ictus en el territorio de la cerebral media izquierda, con restitutio ad integrum.

  18. Reliability of admission cardiotocography for intrapartum monitoring ...

    African Journals Online (AJOL)

    Background To evaluate the role of admission cardiotocography in intrapartum patients in detecting fetal hypoxia already present and to correlate the results of admission cardiotocography with perinatal outcome. Materials and Methods: It was a cross‑sectional study conducted in the Labor and Maternity ward during the ...

  19. Maneuver Automation Software

    Science.gov (United States)

    Uffelman, Hal; Goodson, Troy; Pellegrin, Michael; Stavert, Lynn; Burk, Thomas; Beach, David; Signorelli, Joel; Jones, Jeremy; Hahn, Yungsun; Attiyah, Ahlam; hide

    2009-01-01

    The Maneuver Automation Software (MAS) automates the process of generating commands for maneuvers to keep the spacecraft of the Cassini-Huygens mission on a predetermined prime mission trajectory. Before MAS became available, a team of approximately 10 members had to work about two weeks to design, test, and implement each maneuver in a process that involved running many maneuver-related application programs and then serially handing off data products to other parts of the team. MAS enables a three-member team to design, test, and implement a maneuver in about one-half hour after Navigation has process-tracking data. MAS accepts more than 60 parameters and 22 files as input directly from users. MAS consists of Practical Extraction and Reporting Language (PERL) scripts that link, sequence, and execute the maneuver- related application programs: "Pushing a single button" on a graphical user interface causes MAS to run navigation programs that design a maneuver; programs that create sequences of commands to execute the maneuver on the spacecraft; and a program that generates predictions about maneuver performance and generates reports and other files that enable users to quickly review and verify the maneuver design. MAS can also generate presentation materials, initiate electronic command request forms, and archive all data products for future reference.

  20. Puerperal and intrapartum group A streptococcal infection.

    Science.gov (United States)

    Anteby, E Y; Yagel, S; Hanoch, J; Shapiro, M; Moses, A E

    1999-01-01

    OBJECTIVE: To determine the demographic and clinical variables characteristic of non-epidemic intrapartum or puerperal group A streptococcal (GAS) infection. METHODS: The records of 47 patients diagnosed with intrapartum or puerperal GAS infection over a 6 1/2 year period at Hadassah-University Hospital-Mt. Scopus, Jerusalem were reviewed. Data regarding 25,811 women, the general population of women that delivered during that period, were obtained from their computerized medical records. Frequency distributions, t-test, chi-square, and Spearman's Rank Correlation were used, as appropriate, to analyze and compare demographic and clinical variables associated with development of GAS infection, its clinical course and subsequent development of septic shock. RESULTS: Mean age of mothers with GAS infection was higher than that of our general pregnant population (30.4 versus 27.4 years, P = 0.0019), and a higher proportion of GAS infected patients (30% versus 12%, P < 0.005) experienced PROM. Thirty-one (66%) women had fever as their sole presenting symptom, eight (17%) had fever and abdominal pain, seven (15%) had fever and abnormal vaginal bleeding, and one patient (2%) presented with a rash. Three patients (6%) developed a septic shock. Two of these patients presented with symptoms more than 14 days after delivery. CONCLUSIONS: We describe the characteristics of non-epidemic intrapartum or puerperal GAS infection. Data from our study and review of the literature suggest that some patients who develop septic shock may present later in the puerperium than patients with an uncomplicated GAS infection. PMID:10598916

  1. Intrapartum practices to limit vertical transmission of HIV | du Preez ...

    African Journals Online (AJOL)

    The need to improve health services to HIV-positive women requires a specific focus on limiting mother-to-child transmission. Vertical transmission most often takes place during the intrapartum period; hence, it is essential to alert midwives to what constitutes safe or risky intrapartum practices. Midwives in the southern ...

  2. MORT FŒTALE INTRAPARTUM AU CAMEROUN: Une analyse de ...

    African Journals Online (AJOL)

    9 déc. 2009 ... INTRAPARTUM FETAL DEATH IN CAMEROUN: An assessment in two referral hospitals in Yaounde, ... We thus concluded that specific interventions have to be taken to identify these risk factors of intrapartum fetal death in order to ensure better ..... health programming in developing countries. Paediatr.

  3. Intrapartum maternal fever and neonatal outcome.

    Science.gov (United States)

    Lieberman, E; Lang, J; Richardson, D K; Frigoletto, F D; Heffner, L J; Cohen, A

    2000-01-01

    Much of fever during term labor may not be infectious but rather a consequence of the use of epidural analgesia. Therefore, we investigated the association of elevated maternal intrapartum temperature with neonatal outcome when the infant does not develop an infection. We studied 1218 nulliparous women with singleton, term pregnancies in a vertex presentation and spontaneous labor. Women were excluded if their temperature was >99.5 degrees F at admission for delivery, if they were diabetic or had an active genital herpes infection or if their infant developed a neonatal infection, had a congenital infection, or had a major malformation. Maximum intrapartum temperature was categorized as: 101 degrees F. During labor, 123 women (10.1%) developed a fever >100.4 degrees F; 62 (5.1%) women had a maximum temperature of 100.5 degrees F to 101 degrees F and 61 (5.0%) women had a maximum temperature >101 degrees F. Of febrile women, 97.6% had received epidural analgesia for pain relief. Infants of women developing a fever >100.4 degrees F were more likely to have a 1-minute Apgar score 100.4 degrees F vs 8.0% for afebrile) and to be hypotonic after delivery (4.8% for >100.4 degrees F vs.5% for afebrile). Compared with infants of afebrile women, infants whose mothers' maximum temperature was >101 degrees F were more likely to require bag and mask resuscitation (11.5% vs 3.0%) and to be given oxygen therapy in the nursery (8.2% vs 1.3%). We also found a higher rate of neonatal seizure with fever (3.3% vs.2%), but the number of infants with seizure was small (n = 4). All associations remained essentially the same after controlling for confounding in logistic regression analyses. Intrapartum maternal fever, particularly if >101 degrees F, was associated with a number of apparently transient adverse effects in the newborn. Larger studies are needed to investigate the association of intrapartum fever with neonatal seizures and to determine whether any lasting injury to the fetus

  4. Sinus of Valsalva Aneurysm: A Rare Cause of Dyspnea

    Directory of Open Access Journals (Sweden)

    Aiman Smer

    2015-01-01

    Full Text Available Sinus of Valsalva aneurysm (SOVA is a rare clinical entity. Clinical manifestations can vary from an incidental finding on an imaging study to a life-threatening emergency. We report a case of a 51-year-old female with a large symptomatic left SOVA. Echocardiogram and computed tomography angiography (CTA of the chest revealed marked dilatation of the left sinus of Valsalva, measuring 7.5 cm. This resulted in superior displacement of the left main coronary artery. Surgical repair of the aneurysm with reimplantation of the right and left coronary arteries was performed in addition to aortic valve replacement (Bentall procedure. The patient had an uneventful postoperative course and remains asymptomatic at the three-month follow-up visit.

  5. Toward Army Maneuver Transformation

    National Research Council Canada - National Science Library

    O'Brien, Charles B

    2006-01-01

    ..., can be satisfied to form the nucleus of land domain Force Application formations. This branch will be responsive to the needs of the joint force in Unified Action by adjusting the institutional inputs to force development of Army Maneuver Forces...

  6. Long-term evolution of Valsalva retinopathy: a case series

    Directory of Open Access Journals (Sweden)

    García Fernández Miriam

    2012-10-01

    Full Text Available Abstract Introduction Valsalva retinopathy may occur as a sudden, dramatic loss of central vision due to the premacular location of the haemorrhage. It has been described in different clinical settings, and there are several options for its treatment. Case presentations We present the cases of six patients with sudden visual acuity loss caused by Valsalva retinopathy, treated in our hospital in the last ten years. Case 1 involves a 32-year-old Caucasian man with a unilateral premacular haemorrhage after vomiting. A neodymium-doped yttrium aluminium garnet laser was used due to sufficient depth of the haemorrhage pocket, but it was unsuccessful. Instead, 20G pars plana vitrectomy was performed with excellent visual recuperation (visual acuity:1.0. Case 2 was of a 36-year-old Caucasian woman with Valsalva retinopathy after vomiting during pregnancy. A neodymium-doped yttrium aluminium garnet laser was also insufficient due to the coagulated blood. After labour, 23G pars plana vitrectomy was performed, and her final visual acuity was 1.0. Case 3 involved a 52-year-old Caucasian man with premacular bleeding due to vomiting after general anaesthesia. The haemorrhage did not resolve spontaneously, so 23G pars plana vitrectomy was performed, with excellent visual outcomes (visual acuity:1.0. Case 4 was a 24-year-old Caucasian man with a macular haemorrhage after thoracic trauma. He was observed over four weeks, after which we performed 23G pars plana vitrectomy, with complete visual restoration (visual acuity:1.0. Case 5 involved a 28-year-old man who developed a premacular bleed after vigorous dancing. After a period of observation, 23G pars plana vitrectomy was performed. A retinal break with a small haemorrhage around the break occurred, related to the peribulbar anaesthesia manoeuvers, but was resolved successfully. His final visual acuity was 1.0. Case 6 was a 22-year-old Caucasian woman who developed a premacular haemorrhage after weightlifting

  7. Dominant Maneuver: The Art of the Possible

    National Research Council Canada - National Science Library

    Brozenick, Norman

    1997-01-01

    ...) dominant maneuver, (2) precision engagement, (3) full dimensional protection, and (4) focused logistics. This paper defines dominant maneuver as American maneuver warfare for the early 21st century...

  8. Antenatal and intrapartum prediction of shoulder dystocia.

    Science.gov (United States)

    Gupta, Manish; Hockley, Christine; Quigley, Maria A; Yeh, Peter; Impey, Lawrence

    2010-08-01

    To (1) develop algorithms to calculate the risk of shoulder dystocia at individual deliveries; (2) evaluate screening for shoulder dystocia. Retrospective analysis of 40284 consecutive term cephalic singleton pregnancies using a 'train and test' method. Four models were derived using logistic regression and tested (birthweight alone; birthweight and other independent antenatal variables; birthweight and all independent antenatal and intrapartum variables; and all independent variables excluding birthweight). Shoulder dystocia occurred in 240 deliveries (0.6%). Birthweight was the most important risk factor although 98 cases (41%) occurred in babies weighing shoulder dystocia of >10%. Although the antenatal model had high predictability (area under curve 0.89), it was no better than birthweight alone and had a sensitivity of 52.4%. Where birthweight was excluded, prediction of shoulder dystocia was poor. Antepartum and labour calculation of the risk of shoulder dystocia is possible. Whilst greatly hindered by the inaccuracy of estimating weight, it allows due weight to be given to factors which may already be influencing clinical practice. However, shoulder dystocia cannot be predicted with sufficient accuracy to allow universal screening. Copyright 2010. Published by Elsevier Ireland Ltd.

  9. A comparison of obstetric maneuvers for the acute management of shoulder dystocia.

    Science.gov (United States)

    Hoffman, Matthew K; Bailit, Jennifer L; Branch, D Ware; Burkman, Ronald T; Van Veldhusien, Paul; Lu, Li; Kominiarek, Michelle A; Hibbard, Judith U; Landy, Helain J; Haberman, Shoshana; Wilkins, Isabelle; Quintero, Victor H Gonzalez; Gregory, Kimberly D; Hatjis, Christos G; Ramirez, Mildred M; Reddy, Uma M; Troendle, James; Zhang, Jun

    2011-06-01

    To assess the efficacy of obstetric maneuvers for resolving shoulder dystocia and the effect that these maneuvers have on neonatal injury when shoulder dystocia occurs. Using an electronic database encompassing 206,969 deliveries, we identified all women with a vertex fetus beyond 34 0/7 weeks of gestation who incurred a shoulder dystocia during the process of delivery. Women whose fetuses had a congenital anomaly and women with an antepartum stillbirth were excluded. Medical records of all cases were reviewed by trained abstractors. Cases involving neonatal injury (defined as brachial plexus injury, clavicular or humerus fracture, or hypoxic-ischemic encephalopathy or intrapartum neonatal death attributed to the shoulder dystocia) were compared with those without injury. Among 132,098 women who delivered a term cephalic liveborn fetus vaginally, 2,018 incurred a shoulder dystocia (1.5%), and 101 (5.2%) of these incurred a neonatal injury. Delivery of the posterior shoulder was associated with the highest rate of delivery when compared with other maneuvers (84.4% compared with 24.3-72.0% for other maneuvers; Pshoulder should be considered following the McRoberts maneuver and suprapubic pressure in the management of shoulder dystocia. The need for additional maneuvers was associated with higher rates of neonatal injury.

  10. Sinus of Valsalva Pseudoaneurysm as a Sequela to Infective Endocarditis.

    Science.gov (United States)

    Lee, Chin C; Siegel, Robert J

    2016-02-01

    Pseudoaneurysm is an uncommon sequela of infective endocarditis. We treated a 44-year-old man who had an active case of group B streptococcal infective endocarditis of the aortic valve despite no evidence of valvular dysfunction or vegetation on his initial transesophageal echocardiogram. After completing 6 weeks of intravenous antibiotic therapy, the patient developed a sinus of Valsalva pseudoaneurysm and severe aortic regurgitation caused by partial detachment of the left coronary cusp. We used a pericardial patch to close the pseudoaneurysm and repair the coronary cusp. This case shows the importance of routine clinical follow-up evaluation in infective endocarditis, even after completion of antibiotic therapy. Late sequelae associated with infective endocarditis or its therapy include recurrent infection, heart failure caused by valvular dysfunction (albeit delayed), and antibiotic toxicity such as aminoglycoside-induced nephropathy and vestibular toxicity.

  11. Bacterial Endocarditis Caused by Lactobacillus acidophilus Leading to Rupture of Sinus of Valsalva Aneurysm.

    Science.gov (United States)

    Encarnacion, Carlos Omar; Loranger, Austin Mitchell; Bharatkumar, A G; Almassi, G Hossein

    2016-04-01

    Lactobacillus acidophilus rarely causes bacterial endocarditis, because it usually resides in the mucosa of the vagina, gastrointestinal tract, and oropharynx. Moreover, sinus of Valsalva aneurysms are rare cardiac anomalies, either acquired or congenital. We present the case of a middle-aged man whose bacterial endocarditis, caused by Lactobacillus acidophilus, led to an aneurysmal rupture of the sinus of Valsalva into the right ventricular outflow tract. The patient underwent successful surgical repair, despite numerous complications and sequelae.

  12. Ruptured Sinus of Valsalva Aneurysm and Coarctation of Aorta in a Woman at Early Postpartum Period

    Directory of Open Access Journals (Sweden)

    Erol Sener

    2014-01-01

    Full Text Available Coarctation of aorta and sinus of Valsalva aneurysm are frequently missed congenital cardiac defects that their diagnosis might be delayed. To our knowledge, coincidence of these cardiac defects is unusual and has not been reported in the literature before. Here, we present a patient with coarctation of aorta and ruptured noncoronary sinus of Valsalva aneurysm leading to aorto-right atrial fistula in the early postpartum period and our management of this unusual case.

  13. Associations between intrapartum death and piglet, placental, and umbilical characteristics.

    Science.gov (United States)

    Rootwelt, V; Reksen, O; Farstad, W; Framstad, T

    2012-12-01

    Intrapartum death in multiparous gestations in sows (Sus scrofa) is often caused by hypoxia. There is little information in the literature on the assessment of the placenta in relation to intrapartum death in piglets. The aim of this study was to evaluate the impact of the placental area and weight upon piglet birth characteristics and intrapartum death. Litters from 26 Landrace-Yorkshire sows were monitored during farrowing and the status of each piglet was recorded, including blood parameters of piglets and their umbilical veins. Of 413 piglets born, 6.5% were stillborn. Blood concentrations of glucose, lactate, and CO(2) partial pressure were increased in the stillborn piglets (P live-born piglets, whereas pH and base excess were decreased (P live (P live-born piglets (P = 0.631), whereas mean body mass index was reduced (P live-born piglets (P = 0.662 and P = 0.253, respectively). Blood concentrations of lactate, hemoglobin, and hematocrit recorded in all piglets pooled were associated with placental area (P 0.2). Piglet BW was positively correlated with placental area and placental weight (P vitality than placental weight. Because umbilical cord rupture and prolonged birth time were associated with being born dead, umbilical cord rupture and placental detachment seem to be probable causes of intrapartum death.

  14. Correlation Between Intrapartum Fundal Height and Birth Weight ...

    African Journals Online (AJOL)

    Correlation Between Intrapartum Fundal Height and Birth Weight. HE Onah, ACC Ikeme, PO Nkwo. Abstract. In a prospective cross-sectional study, the correlation between symphysiofundal height (SFH) and birth weight was evaluated in 2646 consecutive parturients at the University of Nigeria Teaching Hospital, Enugu, ...

  15. Barriers to quality care during intrapartum in Buffalo City, Eastern ...

    African Journals Online (AJOL)

    The primary interest of health care workers is the quality of care to patients. Midwives are expected to provide the best level of care for women in all stages of confinement and childbirth. Globally, companionship is becoming an important part of the quality care of women during intrapartum. The purpose of this study was to ...

  16. Intrapartum practices to limit vertical transmission of HIV | du Preez ...

    African Journals Online (AJOL)

    Accordingly, we formulate general recommendations for nursing education, future research, and midwifery practice. In particular we suggest ways the national Guidelines for Maternity Care in South Africa may be adapted and better implemented to enhance safe intrapartum practices to limit vertical transmission of HIV.

  17. Adaptive Maneuvering Target Tracking Algorithm

    Directory of Open Access Journals (Sweden)

    Chunling Wu

    2014-07-01

    Full Text Available Based on the current statistical model, a new adaptive maneuvering target tracking algorithm, CS-MSTF, is presented. The new algorithm keep the merits of high tracking precision that the current statistical model and strong tracking filter (STF have in tracking maneuvering target, and made the modifications as such: First, STF has the defect that it achieves the perfect performance in maneuvering segment at a cost of the precision in non-maneuvering segment, so the new algorithm modified the prediction error covariance matrix and the fading factor to improve the tracking precision both of the maneuvering segment and non-maneuvering segment; The estimation error covariance matrix was calculated using the Joseph form, which is more stable and robust in numerical. The Monte- Carlo simulation shows that the CS-MSTF algorithm has a more excellent performance than CS-STF and can estimate efficiently.

  18. Suction/inspiration against resistance or standardized Mueller maneuver: a new breathing technique to improve contrast density within the pulmonary artery: a pilot CT study

    International Nuclear Information System (INIS)

    Gutzeit, Andreas; Froehlich, Johannes M.; Weymarn, Constantin von; Goyen, Matthias; Waelti, Stephan; Roos, Justus E.; Meissnitzer, Matthias; Hergan, Klaus; Czell, David; Reischauer, Carolin

    2015-01-01

    Our aim was to prospectively investigate whether the recently introduced suction/inspiration against resistance breathing method leads to higher computed tomography (CT) contrast density in the pulmonary artery compared to standard breathing. The present study was approved by the Medical Ethics committee and all subjects gave written informed consent. Fifteen patients, each without suspicious lung emboli, were randomly assigned to four different groups with different breathing maneuvers (suction against resistance, Valsalva, inspiration, expiration) during routine CT. Contrast enhancement in the central and peripheral sections of the pulmonary artery were measured and compared with one another. Peripheral enhancement during suction yielded increased mean densities of 138.14 Hounsfield units (HU) (p = 0.001), compared to Valsalva and a mean density of 67.97 HU superior to inspiration (p = 0.075). Finally, suction in comparison to expiration resulted in a mean increase of 30.51 HU (p = 0.42). Central parts of pulmonary arteries presented significantly increased enhancement values (95.74 HU) for suction versus the Valsalva technique (p = 0.020), while all other mean densities were in favour of suction (versus inspiration: p = 0.201; versus expiration: p = 0.790) without reaching significance. Suction/Inspiration against resistance is a promising technique to improve contrast density within pulmonary vessels, especially in the peripheral parts, in comparison to other breathing maneuvers. (orig.)

  19. Suction/inspiration against resistance or standardized Mueller maneuver: a new breathing technique to improve contrast density within the pulmonary artery: a pilot CT study

    Energy Technology Data Exchange (ETDEWEB)

    Gutzeit, Andreas [Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria); Hirslanden Hospital St. Anna, Institute of Radiology and Nuclear Medicine, Clinical Research Unit, Lucerne (Switzerland); Kantonsspital Winterthur, Department of Radiology, Winterthur (Switzerland); Froehlich, Johannes M.; Weymarn, Constantin von; Goyen, Matthias [Hirslanden Hospital St. Anna, Institute of Radiology and Nuclear Medicine, Clinical Research Unit, Lucerne (Switzerland); Waelti, Stephan [Cantonal Hospital St. Gallen, Department of Radiology and Nuclear Medicine, St. Gallen (Switzerland); Roos, Justus E. [Duke University Medical Center, Department of Radiology, Durham, NC (United States); Meissnitzer, Matthias; Hergan, Klaus [Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria); Czell, David [Cantonal Hospital Winterthur, Department of Neurology, Winterthur (Switzerland); Reischauer, Carolin [Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria); Hirslanden Hospital St. Anna, Institute of Radiology and Nuclear Medicine, Clinical Research Unit, Lucerne (Switzerland)

    2015-11-15

    Our aim was to prospectively investigate whether the recently introduced suction/inspiration against resistance breathing method leads to higher computed tomography (CT) contrast density in the pulmonary artery compared to standard breathing. The present study was approved by the Medical Ethics committee and all subjects gave written informed consent. Fifteen patients, each without suspicious lung emboli, were randomly assigned to four different groups with different breathing maneuvers (suction against resistance, Valsalva, inspiration, expiration) during routine CT. Contrast enhancement in the central and peripheral sections of the pulmonary artery were measured and compared with one another. Peripheral enhancement during suction yielded increased mean densities of 138.14 Hounsfield units (HU) (p = 0.001), compared to Valsalva and a mean density of 67.97 HU superior to inspiration (p = 0.075). Finally, suction in comparison to expiration resulted in a mean increase of 30.51 HU (p = 0.42). Central parts of pulmonary arteries presented significantly increased enhancement values (95.74 HU) for suction versus the Valsalva technique (p = 0.020), while all other mean densities were in favour of suction (versus inspiration: p = 0.201; versus expiration: p = 0.790) without reaching significance. Suction/Inspiration against resistance is a promising technique to improve contrast density within pulmonary vessels, especially in the peripheral parts, in comparison to other breathing maneuvers. (orig.)

  20. Aircraft agility maneuvers

    Science.gov (United States)

    Cliff, Eugene M.; Thompson, Brian G.

    1992-01-01

    A new dynamic model for aircraft motions is presented. This model can be viewed as intermediate between a point-mass model, in which the body attitude angles are control-like, and a rigid-body model, in which the body-attitude angles evolve according to Newton's Laws. Specifically, consideration is given to the case of symmetric flight, and a model is constructed in which the body roll-rate and the body pitch-rate are the controls. In terms of this body-rate model a minimum-time heading change maneuver is formulated. When the bounds on the body-rates are large the results are similar to the point-mass model in that the model can very quickly change the applied forces and produce an acceleration to turn the vehicle. With finite bounds on these rates, the forces change in a smooth way. This leads to a measurable effect of agility.

  1. Support and maneuvering device

    Science.gov (United States)

    Wood, R.L.

    1987-03-23

    A support and maneuvering device includes an elongated flexible inflatable enclosure having a fixed end and a movable end. The movable end is collapsible toward the fixed end to a contracted position when the enclosure is in a noninflated condition. Upon inflation, the movable end is movable away from the fixed end to an extended position. The movable end includes means for mounting an article such as a solar reflector thereon. The device also includes a plurality of position controlling means disposed about the movable end to effect adjusting movement of portions thereof by predetermined amounts and for controlling an angle at which the article disposed at the movable end is oriented. The plurality of position controlling means limits a suitable number degrees of freedom of the movable end for transmitting a steering motion thereto and for controlling the position thereof. 9 figs.

  2. Intrapartum, postpartum characteristics and early neonatal outcomes of idiopathic polyhydramnios.

    Science.gov (United States)

    Karahanoglu, Ertugrul; Ozdemirci, Safak; Esinler, Deniz; Fadıloglu, Erdem; Asiltürk, Seyma; Kasapoglu, Taner; Yalvac, E Serdar; Kandemir, N Omer

    2016-08-01

    This paper investigates the effect of idiopathic polyhydramnios on the intrapartum and postpartum characteristics of labour and early neonatal outcomes. In this study, intrapartum and early neonatal outcomes of 207 women with idiopathic polyhydramnios and 336 matched healthy pregnant patients were evaluated. In the case of idiopathic polyhydramnios, the active phase of labour became longer when compared to the control group (5.76 ± 3.56 h vs. 4.38 ± 2.8 h, p: 001). The risk of preterm birth (OR 5.23; 95% CI: 2.04-13.42) and caesarean section (OR 2.26; 95% CI: 1.56-3.28) was higher in women with IP. Patients with IP had a higher rate of transcient tachypnoea of the newborn (TTN), newborn resuscitation, admission to neonatal intensive care unit (NICU), ventilator requirement, newborn jaundice, newborn hypoglycaemia and structural anomalies. IP did not cause any appreciable maternal risk during the intrapartum or postpartum periods. However, neonatal morbidity and post-natal anomaly rates were higher in the case of IP.

  3. Evaluation of a rapid, real-time intrapartum group B Streptococcus assay

    Science.gov (United States)

    YOUNG, Brett C.; DODGE, Laura E.; GUPTA, Munish; RHEE, Julie S.; HACKER, Michele R.

    2011-01-01

    OBJECTIVE To evaluate an intrapartum nucleic acid amplification test (NAAT) for Group B streptococcus (GBS). STUDY DESIGN Prospective cohort study of 559 women comparing intrapartum GBS culture with antepartum culture and intrapartum NAAT. RESULTS GBS prevalence was 19.5% by antepartum culture and 23.8% by intrapartum culture. Compared with intrapartum culture, antepartum culture had 69.2% sensitivity (60.6–76.9) and 96.0% specificity (93.7–97.7). The NAAT demonstrated sensitivity of 90.8% (84.6–95.2), specificity of 97.6% (95.6–98.8), and predictive values exceeding 92%. The incidence of discordant cultures was 10.4%. Of the women with negative antepartum and positive intrapartum cultures, only 1 (2.4%) received intrapartum antibiotics. Compared with white women, black (P=0.02) and Hispanic (P=0.02) women were more likely to have discordant cultures. CONCLUSION This intrapartum NAAT has excellent characteristics. It may be superior to antepartum culture for detecting intrapartum GBS—allowing more accurate management of laboring mothers and reducing neonatal GBS sepsis. PMID:21864820

  4. Diagnostic paradox: Ruptured aneurysm of sinus of Valsalva simulating tricuspid valve endocarditis.

    Science.gov (United States)

    Hoda, Mehar; Verma, Arushi; Alapati, Sridevi; Alapati, Srilatha; Yarrabolu, Tharakanatha R

    2017-03-01

    Rupture of aneurysm of sinus of Valsalva into the right atrium mimicking tricuspid valve endocarditis is a rare presentation. We review a case of spontaneous rupture of aneurysm of sinus of Valsalva into the right atrium presenting as a murmur. Transthoracic echocardiogram showed a mobile mass that appeared to be attached to the tricuspid valve leaflet with moderate tricuspid regurgitation suggestive of tricuspid valve endocarditis. The diagnosis was confirmed as spontaneous rupture of noncoronary sinus in to the right atrium by transesophageal echocardiogram. Patient recovered completely after surgical repair. © 2017, Wiley Periodicals, Inc.

  5. Maneuver from the Air Domain

    Science.gov (United States)

    2016-05-26

    disarmament after the first Gulf War.127 The roots of the conflict however, go back to the termination of Operation Desert Storm, and Hussein’s...competency of combined arms maneuver, a maneuver mechanism discussed in detail later in this study. 2...Warden’s plan consisted of just eighty-four targets, of which none were Iraqi fielded forces.9 The actual air campaign that took place during Desert

  6. Air Power and Maneuver Warfare

    Science.gov (United States)

    1994-07-01

    way to integrate air power on the one hand with maneuver warfare on the other. While American commanders such as Robert E. Lee and George S. Patton...MANEUVER WARFARE years .’ Nevertheless, it should not be forgotten that few commanders of any time or place have fought as many great battles- batailles ...the process to a boxer who uses one arm to parry his opponent’s punches and draw his attention while striking with the other. Gen George S. Patton

  7. 14 CFR 25.1507 - Maneuvering speed.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Maneuvering speed. 25.1507 Section 25.1507....1507 Maneuvering speed. The maneuvering speed must be established so that it does not exceed the design maneuvering speed V A determined under § 25.335(c). ...

  8. Rupture of sinus of Valsalva aneurysm into both right atrium and ...

    African Journals Online (AJOL)

    A young man had a congenital sinus of Valsalva aneurysm originating from the right coronary sinus, complicated by fistulas draining into both right atrium and right ventricle, as well as a congenitally abnormal aortic valve with mild aortic insufficiency. His dramatic clinical presentation, with the sudden appearance of severe ...

  9. of Valsalva aneurysm atrium and right Rupture of sinus into both ...

    African Journals Online (AJOL)

    1983-04-16

    Apr 16, 1983 ... bacterial endocarditis..giving rise to a mycotic aneurysm. 11 Syphi- lis is said to be a most unusual cause, and so is rupture due to severe rheumatoid heart diseaseY. Asingle rupture with fistula formation is by far the most usual consequence of a sinus of Valsalva aneurysm, which is usually single. The only ...

  10. Transcatheter closure of ruptured sinus of valsalva aneurysms: evaluation of therapeutic results

    International Nuclear Information System (INIS)

    Wu Guangwei; Xu Nengwen; Wang Mengjie; Wu Xubin

    2014-01-01

    Objective: To discuss the clinical effects and safety, of transcatheter closure in treating ruptured sinus of valsalva aneurysm (RSVA). Methods: During the period from May 2007 to June 2012, 5 patients (4 males and 1 female) with RSVA were treated with interventional occlusion therapy at authors' hospital. The aortic root angiography and echocardiography indicated that all the five patients had single sinus of valsalva aneurysm, including rupture of right coronary sinus of valsalva aneurysm into the right ventricle (n=3) and into the right atrium (n=2). Results: The occluder placement was successfully accomplished in all the 5 patients. Patent arterial duct occluder was employed in two patients, while ventricular septal defect occluder was adopted in three patients, After the procedure, the five patients were followed up for 12- 60 months (mean 30.2 months), and echocardiography and electrocardiography were conducted to evaluate the clinical effects. After the interventional occlusion therapy, in all patients the inner-diameters of the right ventricular and right atrium were markedly reduced, and the heart murmur disappeared. The occluder was situated in the right place. No complications such as hemolysis or aortic regurgitation occurred. Conclusion: Transcatheter closure is a mini-invasive, safe, simple and effective technique for the treatment of ruptured sinus of valsalva aneurysm. The short-term result is satisfactory, although its long-term efficacy needs to be further studied. (authors)

  11. Transthoracic Echocardiography versus Transesophageal Echocardiography for Rupture Sinus of Valsalva Aneurysm

    Science.gov (United States)

    Dhawan, Ira; Malik, Vishwas; Sharma, Kamal Prakash; Makhija, Neeti; Pangasa, Neha

    2017-01-01

    We report a rare case of sinus of Valsalva aneurysm of both right and left coronary sinus (LCS), with perforation of the LCS opening into the left ventricle. The LCS aneurysm with its perforation was undiagnosed on transthoracic echocardiography emphasizing the role of transesophageal echocardiography in delineating the anatomy. PMID:28393788

  12. Transcatheter device closure of multiple defects in ruptured sinus of Valsalva aneurysm

    Directory of Open Access Journals (Sweden)

    A. Vamsidhar

    2015-12-01

    Full Text Available Ruptured sinus of Valsalva aneurysm (SOVA with multiple communications, ventricular septal defect, and aortic regurgitation are still best treated surgically. We report a case of 30-year-old male with right SOVA, with two communications with right ventricle. Both communications were successfully closed using antegrade and retrograde approaches, respectively.

  13. Understanding the Full Spectrum of Organ Injury Following Intrapartum Asphyxia

    Science.gov (United States)

    LaRosa, Domenic A.; Ellery, Stacey J.; Walker, David W.; Dickinson, Hayley

    2017-01-01

    Birth asphyxia is a significant global health problem, responsible for ~1.2 million neonatal deaths each year worldwide. Those who survive often suffer from a range of health issues including brain damage—manifesting as cerebral palsy (CP)—respiratory insufficiency, cardiovascular collapse, and renal dysfunction, to name a few. Although the majority of research is directed toward reducing the brain injury that results from intrapartum birth asphyxia, the multi-organ injury observed in surviving neonates is of equal importance. Despite the advent of hypothermia therapy for the treatment of hypoxic–ischemic encephalopathy (HIE), treatment options following asphyxia at birth remain limited, particularly in low-resource settings where the incidence of birth asphyxia is highest. Furthermore, although cooling of the neonate results in improved neurological outcomes for a small proportion of treated infants, it does not provide any benefit to the other organ systems affected by asphyxia at birth. The aim of this review is to summarize the current knowledge of the multi-organ effects of intrapartum asphyxia, with particular reference to the findings from our laboratory using the precocial spiny mouse to model birth asphyxia. Furthermore, we reviewed the current treatments available for neonates who have undergone intrapartum asphyxia, and highlight the emergence of maternal dietary creatine supplementation as a preventative therapy, which has been shown to provide multi-organ protection from birth asphyxia-induced injury in our preclinical studies. This cheap and effective nutritional supplement may be the key to reducing birth asphyxia-induced death and disability, particularly in low-resource settings where current treatments are unavailable. PMID:28261573

  14. Intrapartum analgesia as a condition of human satisfaction at hospital

    Directory of Open Access Journals (Sweden)

    Concetta Polizzi

    2013-06-01

    Full Text Available The study investigates parturients’ satisfaction with intrapartum analgesia. It aims to assess their opinions about hospital and health staff involved in delivery, besides investigating emotional control, locus control and bond between mothers and their newborn infants. A multidimensional approach has been used to investigate the variable of woman as a person, the variable of context and the variable of bond with the newborn infant. The study was conducted according to a quasi-experimental design, with a control group. The study was performed within the Analgesia and Intensive Care Operational Unit of the Maternal-Infant Department of the P. Giaccone University General Hospital of Palermo. It involved 60 women subdivided into two groups of 30 women each, the experimental group (women who requested intrapartum analgesia called the A group, and the control group (women who refused it called the B group. The following tools were administered: the STAI-Y (State-Trait Anxiety Inventory, form Y scale; the Depression Questionnaire of CBA (Cognitive Behavioural Assessment scale; the Locus of Control questionnaire; and an interview designed for the purpose. The experimental A group women exhibited lower levels of state anxiety and depression post-partum than those of the control B group; moreover, the women in the A group exhibited higher levels of external locus of control and evaluated delivery more positively than those of the B group. There were no significant differences with regard to the relationship with their newborn infants. The study shows that intrapartum analgesia provides hospitals with the possibility to satisfy women’s needs for safety and well-being.

  15. Mort foetal intrapartum au Cameroun: Une analyse de deux ...

    African Journals Online (AJOL)

    Selon le rapport de l'organisation mondiale de la santé sur l'Afrique, 4.1% de nouveau nés meurent avant d'être nés, 37% de ces décès surviennent pendant le travail. Nous avons engagé ce travail afin d'identifier les facteurs de risque de mortalité intrapartum dans notre milieu. Dans une étude cas- témoins réalisée du 1er ...

  16. Suction/Inspiration against resistance or standardized Mueller maneuver : a new breathing technique to improve contrast density within the pulmonary artery: a pilot CT study.

    Science.gov (United States)

    Gutzeit, Andreas; Froehlich, Johannes M; Wälti, Stephan; Roos, Justus E; Meissnitzer, Matthias; Hergan, Klaus; von Weymarn, Constantin; Czell, David; Goyen, Matthias; Reischauer, Carolin

    2015-11-01

    Our aim was to prospectively investigate whether the recently introduced suction/inspiration against resistance breathing method leads to higher computed tomography (CT) contrast density in the pulmonary artery compared to standard breathing. The present study was approved by the Medical Ethics committee and all subjects gave written informed consent. Fifteen patients, each without suspicious lung emboli, were randomly assigned to four different groups with different breathing maneuvers (suction against resistance, Valsalva, inspiration, expiration) during routine CT. Contrast enhancement in the central and peripheral sections of the pulmonary artery were measured and compared with one another. Peripheral enhancement during suction yielded increased mean densities of 138.14 Hounsfield units (HU) (p = 0.001), compared to Valsalva and a mean density of 67.97 HU superior to inspiration (p = 0.075). Finally, suction in comparison to expiration resulted in a mean increase of 30.51 HU (p = 0.42). Central parts of pulmonary arteries presented significantly increased enhancement values (95.74 HU) for suction versus the Valsalva technique (p = 0.020), while all other mean densities were in favour of suction (versus inspiration: p = 0.201; versus expiration: p = 0.790) without reaching significance. Suction/Inspiration against resistance is a promising technique to improve contrast density within pulmonary vessels, especially in the peripheral parts, in comparison to other breathing maneuvers. • Suction/Inspiration against resistance is promising to improve contrast density within the pulmonary artery. • Patients potentially suffering pulmonary embolism are able to follow suction/inspiration against resistance. • Contrast density after suction is superior in comparison to other breathing maneuvers.

  17. Dynamics of Voluntary Cough Maneuvers

    Science.gov (United States)

    Naire, Shailesh

    2008-11-01

    Voluntary cough maneuvers are characterized by transient peak expiratory flows (PEF) exceeding the maximum expiratory flow-volume (MEFV) curve. In some cases, these flows can be well in excess of the MEFV, generally referred to as supramaximal flows. Understanding the flow-structure interaction involved in these maneuvers is the main goal of this work. We present a simple theoretical model for investigating the dynamics of voluntary cough and forced expiratory maneuvers. The core modeling idea is based on a 1-D model of high Reynolds number flow through flexible-walled tubes. The model incorporates key ingredients involved in these maneuvers: the expiratory effort generated by the abdominal and expiratory muscles, the glottis and the flexibility and compliance of the lung airways. Variations in these allow investigation of the expiratory flows generated by a variety of single cough maneuvers. The model successfully reproduces PEF which is shown to depend on the cough generation protocol, the glottis reopening time and the compliance of the airways. The particular highlight is in simulating supramaximal PEF for very compliant tubes. The flow-structure interaction mechanisms behind these are discussed. The wave speed theory of flow limitation is used to characterize the PEF. Existing hypotheses of the origin of PEF, from cough and forced expiration experiments, are also tested using this model.

  18. Professionally responsible intrapartum management of patients with major mental disorders.

    Science.gov (United States)

    Babbitt, Kriste E; Bailey, Kala J; Coverdale, John H; Chervenak, Frank A; McCullough, Laurence B

    2014-01-01

    Pregnant women with major mental disorders present obstetricians with a range of clinical challenges, which are magnified when a psychotic or agitated patient presents in labor and there is limited time for decision making. This article provides the obstetrician with an algorithm to guide professionally responsible decision making with these patients. We searched for articles related to the intrapartum management of pregnant patients with major mental disorders, using 3 main search components: pregnancy, chronic mental illness, and ethics. No articles were found that addressed the clinical ethical challenges of decision making during the intrapartum period with these patients. We therefore developed an ethical framework with 4 components: the concept of the fetus as a patient; the presumption of decision-making capacity; the concept of assent; and beneficence-based clinical judgment. On the basis of this framework we propose an algorithm to guide professionally responsible decision making that asks 5 questions: (1) Does the patient have the capacity to consent to treatment?; (2) Is there time to attempt restoration of capacity?; (3) Is there an opportunity for substituted judgment?; (4) Is the patient accepting treatment?; (5) Is there an opportunity for active assent?; and (6) coerced clinical management as the least worst alternative. The algorithm is designed to support a deliberative, clinically comprehensive, preventive-ethics approach to guide obstetricians in decision making with this challenging population of patients. Copyright © 2014 Mosby, Inc. All rights reserved.

  19. Comparison of Valsalva manoeuvre and exercise in echocardiographic evaluation of left ventricular outflow tract obstruction in hypertrophic cardiomyopathy

    DEFF Research Database (Denmark)

    Jensen, Morten Krogh; Havndrup, Ole; Pecini, Redi

    2010-01-01

    Several methods are used to induce latent left ventricular outflow tract (LVOT) gradients in patients with hypertrophic cardiomyopathy (HCM). We compared LVOT gradients induced by Valsalva manoeuvre (VM) and exercise echocardiography (EE) in patients with HCM treated with percutaneous transluminal...

  20. A single-center randomized controlled trial observing the safety and efficacy of modified step-up graded Valsalva manoeuver in patients with vasovagal syncope.

    Directory of Open Access Journals (Sweden)

    Li He

    Full Text Available Non-pharmacological therapies, especially the physical maneuvers, are viewed as important and promising strategies for reducing syncope recurrences in vasovagal syncope (VVS patients. We observed the efficacy of a modified Valsalva maneuver (MVM in VVS patients. 72 VVS patients with syncope history and positive head-up tilt table testing (HUTT results were randomly divided into conventional treatment group (NVM group, n = 36 and conventional treatment plus standard MVM for 30 days group (MVM group, n = 36. Incidence of recurrent syncope after 12 months (6.5% vs. 41.2%, P<0.01 and rate of positive HUTT after 30 days (9.7% vs.79.4%, P<0.01 were significantly lower in MVM group than in NVM group. HRV results showed that low frequency (LF, LF/ high frequency (HF, standard deviation of NN intervals (SDNN and standard deviation of all 5-min average NN intervals (SDANN values were significantly lower in the NVM and MVM groups than in the control group at baseline. After 30 days treatment, LF, LF/HF, SDNN, SDANN values were significantly higher compared to baseline in MVM group. Results of Cox proportional hazard model showed that higher SDNN and SDANN values at 30 days after intervention were protective factors, while positive HUTT at 30 days after intervention was risk factor for recurrent syncope. Our results indicate that 30 days MVM intervention could effectively reduce the incidence of recurrent syncope up to 12 months in VVS patients, possibly through improving sympathetic function of VVS patients.

  1. [Intrapartum asphyxia: Risk factors and short-term consequences].

    Science.gov (United States)

    Bouiller, J-P; Dreyfus, M; Mortamet, G; Guillois, B; Benoist, G

    2016-06-01

    Intrapartum asphyxia is a rare yet serious complication during labor with immediate consequences and possible long-term neurological impairment. The international Cerebral Palsy Task Force established criteria that attribute a cerebral palsy to intrapartum asphyxia: metabolic acidemia measured at birth with pHasphyxia occurring in term live births, to evaluate the short-term consequences. Our retrospective study included all births between 2002 and 2010 in a level 3 maternity of a university hospital center. Inclusion criteria were those of the Cerebral Palsy Task Force associated with a gestational age≥34weeks of gestation. We studied the conventional markers of intrapartum asphyxia: Apgar score at 5minutes, abnormal cardiotogographic recordings whether they occurred after a sentinel hypoxic event or not before and during labor. The duration of expulsive efforts, the amniotic fluid aspects, the delivery mode as well as the preexisting pregnancy pathologies were also evaluated. On the other hand, we studied the short-term consequences at the newborns: death, multiorgan failure and especially the occurring of a neonatal encephalopathy using Sarnat and Sarnat staging. One hundred and twenty-nine newborns (0.43%) out of 29,416 live births had a pHasphyxia and were included in this study. A preexisting pregnancy pathology was found in 22% of the women. Hypoxic events were noted in only 9/82 of the cases. Abnormal cardiotocographic recordings were present in 97.6% of the cases. The duration of expulsive efforts as well as the amniotic fluid aspects did not interfere with the occurring of a metabolic acidemia. Caesarean rate was at 46.3% and instrumental extraction rate was at 34.1%. Thity-eight newborns (46.3%) were admitted in neonatal intensive care in which we noted 3 deaths (3.65%), 2 multiorgan failures (2.4%) and 17 neonatal encephalopathy (20.7%). The pH value seemed to influence the occurring of an encephalopathy: 50% when pHneonatal encephalopathy

  2. Rare cause of right heart failure: contained rupture of a sinus of Valsalva aneurysm associated intraventricular septal aneurysm.

    Science.gov (United States)

    Mookadam, F; Haley, J; Mendrick, Ed

    2005-06-01

    Sinus of Valsalva aneurysm (SVA) is a rare congenital lesion described first in 1840 by John Thurnam (Cited by Boutefou JM, Moret PR, Hahn C, Hanf E. Aneurysms of the sinus of Valsalva: report of seven cases and review of the literature. Am J Med 1978;65:18-24). In most cases unruptured Sinus of Valsalva aneurysm (SVA) is clinically silent; however, if it progressively enlarges it may cause coronary artery compression, complete heart block, or right ventricular outflow tract obstruction (Meier JH, Seward JD, Miller FA, Oh J, Sarano ME. Aneurysms in the left ventricular outflow tract: clinical presentation, causes, and echocardiographic features. J Am Soc Echocardiogr 1998;11:729-45; D'Silva SA, Dalve BV, Lokhandwala YY, Kale PA, Tendolkar AG. Unruptured congenital aneurysm of the left sinus of Valsalva presenting as acute right heart failure. Chest 1992;101:578-79) or is a potential source of cerebrovascular emboli. (Shahrabani RM, Jairaj PS. Unruptured aneurysm of the sinus of Valsalva: a potential source of cerebrovascular embolism. Br Heart J 1993;69:266-67). In this report, we describe a case of right coronary sinus of Valsalva aneurysm with a contained rupture. The containing rupture is in intraventricular septal aneurysm; the patient presents with right-sided heart failure.

  3. Single coronary artery originating from the right sinus Valsalva and ability to work.

    Science.gov (United States)

    De Rosa, Roberto; Ratti, Gennaro; Gerardi, Donato; Tedeschi, Carlo; Lamberti, Monica

    2015-01-01

    We present a case of a 56-year-old male electrician who was admitted to the hospital with atrial fibrillation, atypical chest pain and dyspnea. He gave a history that on the morning he had working for almost 4 hours carrying out various activities with considerable physical effort. After cardioversion, conventional coronary angiography revealed a suspect of single coronary vessel (SCA) arising from the right sinus of Valsalva. The patient underwent multislice computed tomography that showed a SCA arising from the right sinus Valsalva and dividing in Right Coronary Artery (RCA) and Left Main coronary artery (LM). The finding of posterior course of the LM without atherosclerotic has proved crucial for the expression of an opinion of working capacity even with limitation.

  4. Simultaneous transcatheter closure of ruptured sinus of Valsalva aneurysm and stent implantation for aortic coarctation

    Directory of Open Access Journals (Sweden)

    Jivtesh S. Pahwa

    2015-12-01

    Full Text Available Ruptured sinus of Valsalva aneurysm is a rare anomaly and an associated coarctation of aorta is even rarer. A combination of such defects is traditionally treated surgically. The surgery is necessarily staged and done through different approaches. We report successful simultaneous transcatheter treatment of both these defects performed in the same setting in an acutely ill adult male patient with a good intermediate-term follow-up.

  5. Morbidly Adherent Placenta: Interprofessional Management Strategies for the Intrapartum Period.

    Science.gov (United States)

    Baird, Suzanne McMurtry; Troiano, Nan H; Kennedy, Margaret Betsy Babb

    "Morbidly adherent placenta" is a term that describes the continuum of placenta accreta, increta, and percreta. The incidence of this type of abnormal placentation has increased significantly over recent decades. The reason is probably multifactorial but, partly, because of factors such as the increasing number of cesarean births. Women at greatest risk are those who have myometrial damage caused by a previous cesarean birth, with either anterior or posterior placenta previa overlying the uterine scar. This condition poses significant risks of morbidity and/or mortality to the pregnant woman and her fetus. A multidisciplinary approach to care throughout pregnancy is essential. This article describes the classification of morbidly adherent placenta, risk factors, methods of diagnosis, potential maternal and fetal complications, and intrapartum clinical management strategies to optimize outcomes.

  6. Intrapartum amnioinfusion for meconium-stained liquor in developing countries.

    Science.gov (United States)

    Moodley, J; Matchaba, P; Payne, A J

    1998-01-01

    Intrapartum amnioinfusion (AI) has been reported to decrease perinatal mortality and morbidity in women with meconium-stained liquor. Such work has not previously been performed at King Edward VIII Hospital (KEH), in a developing country, where the incidence of meconium-stained liquor is said to be extremely high. To establish whether AI during the intrapartum period for meconium-stained liquor decreases Caesarean section rates for fetal distress and decreases perinatal morbidity. Informed consent was obtained from patients in labour who were 3-8 cm dilated, with meconium-staining of the liquor, grades I to III inclusive, and who had a normal cardiotocograph on presentation at term. Sixty patients were included in the trial; 30 had AI. The control group was managed by standard methods. The study group had an amnioinfusion of 0.9% normal saline at 15 ml/min under continuous cardiotocographic monitoring, until a volume of 11 was completed. This was repeated if delivery did not occur within 4 h. The mean pH of umbilical arterial blood was significantly higher in the AI group (7.30 versus 7.23; P = 0.0029). In addition fewer patients in this group developed hypoxic ischaemic encephalopathy (0 versus 2 controls) or meconium aspiration syndrome (1 versus 4 controls). This was not statistically significant. Caesarean section for fetal distress was performed on fewer patients in the AI group (3 versus 7 controls), although this was not statistically significant. These results demonstrate that amnioinfusion is an effective technique for improving the perinatal outcome of pregnancies complicated by meconium-stained liquor in labour. The decrease in Caesarean sections for fetal distress, though not statistically significant in this study, has clinical relevance. Furthermore, this study suggests that amnioinfusion is cost effective in a busy, high-risk labour ward unit and consequently should become standard practice in the management of meconium-stained liquor in labour.

  7. Acute Effect on Arterial Stiffness after Performing Resistance Exercise by Using the Valsalva Manoeuvre during Exertion

    Directory of Open Access Journals (Sweden)

    Wai Yip Vincent Mak

    2015-01-01

    Full Text Available Background. Performing resistance exercise could lead to an increase in arterial stiffness. Objective. We investigate the acute effect on arterial stiffness by performing Valsalva manoeuvre during resistance exercise. Materials and Methods. Eighteen healthy young men were assigned to perform bicep curls by using two breathing techniques (exhalation and Valsalva manoeuvre during muscle contraction on two separate study days. Carotid pulsed wave velocity (cPWV was measured as an indicator to reflect the body central arterial stiffness using a high-resolution ultrasound system, and its value was monitored repeatedly at three predefined time intervals: before resistance exercise, immediately after exercise, and 15 minutes after exercise. Results. At the 0th minute after resistance exercise was performed using the Valsalva manoeuvre during exertion, a significant increase in cPWV (4.91 m/s ± 0.52 compared with the baseline value (4.67 m/s ± 0.32, P=0.008 was observed, and then it nearly returned to its baseline value at the 15th minute after exercise (4.66 m/s ± 0.44, P=0.010. These findings persisted after adjusting for age, body mass index, and systolic blood pressure. Conclusion. Our result suggests short duration of resistance exercise may provoke a transient increase in central arterial stiffness in healthy young men.

  8. Valsalva-Related Subretinal Hemorrhage as a Presenting Symptom of Polypoidal Choroidal Vasculopathy

    Directory of Open Access Journals (Sweden)

    Yousif Subhi

    2017-01-01

    Full Text Available Purpose. To describe a case of Valsalva-related subretinal hemorrhage as a presenting symptom of polypoidal choroidal vasculopathy (PCV. The patient refrained from treatment against our best advice, and thus this is also a rare case of the natural course of an untreated PCV. Methods. Case report. Results. A 66-year-old female with a respiratory infection coughed intensely until exhaustion, after which she developed visual symptoms on the right eye. Primary care ophthalmologist examined the patient on the same day of the onset of symptoms and referred her to our tertiary medical retinal service for detailed retinal diagnosis including fluorescein and indocyanine green angiography. The right eye had a large subretinal hemorrhage and pigment epithelium detachment in the lower temporal arcade with foveal involvement. Against our best advice, the patient refused treatment. In the following 9 months, the BCVA decreased from 68 to 55 ETDRS letters, the subretinal hemorrhage almost regressed, pigment epithelium detachments persisted, and macular edema, intraretinal cysts, and subretinal fibrosis developed. Conclusions. Although classic Valsalva retinopathy with preretinal hemorrhage in most cases can be managed by careful observation and no treatment, this case demonstrates that Valsalva-related subretinal hemorrhage needs different attention and approach.

  9. Hemodynamics in the Valsalva sinuses after transcatheter aortic valve implantation (TAVI).

    Science.gov (United States)

    Ducci, Andrea; Tzamtzis, Spyridon; Mullen, Michael J; Burriesci, Gaetano

    2013-09-01

    The study aim was to assess, in vitro, the hemodynamic modifications produced by transcatheter valves in the Valsalva sinuses, by mean of phase-resolved particle image velocimetry (PIV) measurements. Flow measurements were performed on a glass mock aortic root that included three polymeric valve leaflets, before and after the implantation of a Medtronic CoreValve device and of an Edwards SAPIEN valve. All experiments were carried out in a hydro-mechanical cardiovascular pulse duplicator system (Vivitro Superpump System SP3891) that reproduced physiologically equivalent pressures and flow rates conforming to the requirements of the standard ISO 5840:2005. The flow dynamics, before and after implantation of the two prosthetic devices, was characterized on the basis of phase-resolved velocity field and viscous shear rate measurements. Direct comparison indicated that both transcatheter valves determined a significant variation of flow during the early stages of valve opening and during valve closure. In general, the presence of the two valve implants significantly reduced the flow activity in the Valsalva sinuses, promoting regions of stagnation at their base. The reduction in flow in the Valsalva sinuses could be associated with the higher incidence of ischemic events reported after transcatheter heart valve implantation.

  10. Sudden onset congestive heart failure with a continuous murmur: ruptured sinus of Valsalva aneurysm complicated by anomalous origin of the left coronary artery.

    Science.gov (United States)

    Seto, Arnold H; Hermer, Alan; Kern, Morton

    2008-01-01

    Ruptured sinus of Valsalva aneurysm is an unusual cause for congestive heart failure, and anomalous coronary arteries have rarely been found in association. A 47-year-old man developed sudden onset heart failure due to a ruptured noncoronary sinus of Valsalva fistula to the right atrium. Coronary angiography revealed an anomalous left coronary artery arising from the right coronary sinus, limiting percutaneous options for repair. We review the incidence, complications, and management of sinus of Valsalva aneurysms and anomalous left coronary arteries.

  11. Maternal infection and risk of intrapartum death: a population based observational study in South Asia

    Science.gov (United States)

    2013-01-01

    Background Approximately 1.2 million stillbirths occur in the intrapartum period, and a further 717,000 annual neonatal deaths are caused by intrapartum events, most of which occur in resource poor settings. We aim to test the ‘double-hit’ hypothesis that maternal infection in the perinatal period predisposes to neurodevelopmental sequelae from an intrapartum asphyxia insult, increasing the likelihood of an early neonatal death compared with asphyxia alone. This is an observational study of singleton newborn infants with signs of intrapartum asphyxia that uses data from three previously conducted cluster randomized controlled trials taking place in rural Bangladesh and India. Methods From a population of 81,778 births in 54 community clusters in rural Bangladesh and India, we applied mixed effects logistic regression to data on 3890 singleton infants who had signs of intrapartum asphyxia, of whom 769 (20%) died in the early neonatal period. Poor infant condition at five minutes post-delivery was our proxy measure of intrapartum asphyxia. We had data for two markers of maternal infection: fever up to three days prior to labour, and prolonged rupture of membranes (PROM). Cause-specific verbal autopsy data were used to validate our findings using previously mentioned mixed effect logistic regression methods and the outcome of a neonatal death due to intrapartum asphyxia. Results Signs of maternal infection as indicated by PROM, combined with intrapartum asphyxia, increased the risk of an early neonatal death relative to intrapartum asphyxia alone (adjusted odds ratio (AOR) 1.28, 95% CI 1.03 – 1.59). Results from cause-specific verbal autopsy data verified our findings where there was a significantly increased odds of a early neonatal death due to intrapartum asphyxia in newborns exposed to both PROM and intrapartum asphyxia (AOR: 1.52, 95% CI 1.15 – 2.02). Conclusions Our data support the double-hit hypothesis for signs of maternal infection as indicated by

  12. Correlation between indexes of autonomic maneuvers and heart rate variability in hemodialysis patients.

    Science.gov (United States)

    Vieira, Carlos Felipe Delmondes; Lima, Márcia Maria Oliveira; Costa, Henrique Silveira; Diniz, Karen Marina Alves; Guião, João Paulo Lemos; Alves, Frederico Lopes; Maciel, Emílio Henrique; Brandao, Vanessa Gomes; Figueiredo, Pedro Henrique Scheidt

    2016-06-01

    The autonomic maneuvers are simple methods to evaluate autonomic balance, but the association between autonomic maneuvers and heart rate variability (HRV) in hemodialysis patients remains unknown. This study aimed to evaluate the correlation between HRV and respiratory sinus arrhythmia (RSA) and Valsalva maneuver (VM) indexes in hemodialysis patients and to compare two methods for RSA indexes acquisitions. Forty-eight volunteers on hemodialysis (66.7 % men) were evaluated by VM, RSA, and 24 h Holter monitoring. At the VM, the Valsalva index (VI) was the variable considered. In the RSA, the ratio and difference between the RR intervals of inspiratory and expiratory phase (E:I and E-I, respectively) were considered by traditional form (average of respiratory cycles) and independent respiratory cycles (E:Iindep and E-Iindep). The HRV indexes evaluated were standard deviation of all normal RR intervals (SDNN), standard deviation of sequential 5-min RR interval means (SDANN), root mean square of the successive differences (rMSSD) and percentage of adjacent RR intervals with difference of duration greater than 50 ms (pNN50). The SDNN, SDANN showed significant correlation with all classic indexes of RSA (E:I: r = 0.62, 0.55, respectively, E-I: r = 0.64, 0.57, respectively), E:Iindep (r = 0.59, 0.54, respectively), E-Iindep (r = 0.47, 0.43, respectively) and VI (r = 0.42, 0.34, respectively). Significant correlation of rMSSD with E:I (r = 0.37), E-I (r = 0.41) and E:Iindep (r = 0.34) was also observed. There was no association of any variable with pNN50. Have been show high values for all variables of independent cycles method (p index by independent cycles should not be used in this population.

  13. Plotting Orbital Trajectories For Maneuvers

    Science.gov (United States)

    Brody, Adam R.

    1991-01-01

    Interactive Orbital Trajectory Planning Tool (EIVAN) computer program is forward-looking interactive orbit-trajectory-plotting software tool for use with proximity operations (operations occurring within 1-km sphere of space station) and other maneuvers. Developed to plot resulting trajectories, to provide better comprehension of effects of orbital mechanics, and to help user develop heuristics for planning missions on orbit. Program runs with Microsoft's Excel for execution on MacIntosh computer running MacIntosh OS.

  14. The maneuver search and the maneuver search trajectory framework of search heavy torpedo

    Science.gov (United States)

    Yin, Wenjin; Zhang, Jingyuan; Li, Jitao

    2016-01-01

    With the development of technology capability of submarine launching heavy torpedo and the demand of intellectualized combat, the paper raises the concept of torpedo maneuver search and analyses maneuver search opportunity. It is necessary to realize the long range heavy torpedo's maneuver search that heavy torpedo's maneuver search can cover the target's location error which results from launching platform's position precision and the target's intentional maneuver when the torpedo is launched. The technology framework of the heavy torpedo's maneuver search trajectory is set up.

  15. [Risks factors associated with intra-partum foetal mortality in pre-term infants].

    Science.gov (United States)

    Zeballos Sarrato, Susana; Villar Castro, Sonia; Ramos Navarro, Cristina; Zeballos Sarrato, Gonzalo; Sánchez Luna, Manuel

    2017-03-01

    Pre-term delivery is one of the leading causes of foetal and perinatal mortality. However, perinatal risk factors associated with intra-partum foetal death in preterm deliveries have not been well studied. To analyse foetal mortality and perinatal risk factors associated with intra-partum foetal mortality in pregnancies of less than 32 weeks gestational age. The study included all preterm deliveries between 22 and 31 +1 weeks gestational age (WGA), born in a tertiary-referral hospital, over a period of 7 years (2008-2014). A logistic regression model was used to identify perinatal risk factors associated with intra-partum foetal mortality (foetal malformations and chromosomal abnormalities were excluded). During the study period, the overall foetal mortality was 63.1% (106/168) (≥22 weeks of gestation) occurred in pregnancies of less than 32 WGA. A total of 882 deliveries between 22 and 31+6 weeks of gestation were included for analysis. The rate of foetal mortality was 11.3% (100/882). The rate of intra-partum foetal death was 2.6% (23/882), with 78.2% (18/23) of these cases occurring in hospitalised pregnancies. It was found that Assisted Reproductive Techniques, abnormal foetal ultrasound, no administration of antenatal steroids, lower gestational age, and small for gestational age, were independent risk factors associated with intra-partum foetal mortality. This study showed that there is a significant percentage intra-partum foetal mortality in infants between 22 and 31+6 WGA. The analysis of intrapartum mortality and risk factors associated with this mortality is of clinical and epidemiological interest to optimise perinatal care and improve survival of preterm infants. Copyright © 2016 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Intrapartum epidural analgesia and breastfeeding: a prospective cohort study

    Directory of Open Access Journals (Sweden)

    Simpson Judy M

    2006-12-01

    Full Text Available Abstract Background Anecdotal reports suggest that the addition of fentanyl (an opioid to epidural analgesia for women during childbirth results in difficulty establishing breastfeeding. The aim of this paper is to determine any association between epidural analgesia and 1 breastfeeding in the first week postpartum and 2 breastfeeding cessation during the first 24 weeks postpartum. Methods A prospective cohort study of 1280 women aged ≥ 16 years, who gave birth to a single live infant in the Australian Capital Territory in 1997 was conducted. Women completed questionnaires at weeks 1, 8, 16 and 24 postpartum. Breastfeeding information was collected in each of the four surveys and women were categorised as either fully breastfeeding, partially breastfeeding or not breastfeeding at all. Women who had stopped breastfeeding since the previous survey were asked when they stopped. Results In the first week postpartum, 93% of women were either fully or partially breastfeeding their baby and 60% were continuing to breastfeed at 24 weeks. Intrapartum analgesia and type of birth were associated with partial breastfeeding and breastfeeding difficulties in the first postpartum week (p Conclusion Women in this cohort who had epidurals were less likely to fully breastfeed their infant in the few days after birth and more likely to stop breastfeeding in the first 24 weeks. Although this relationship may not be causal, it is important that women at higher risk of breastfeeding cessation are provided with adequate breastfeeding assistance and support.

  17. Factors affecting midwives' confidence in intrapartum care: a phenomenological study.

    Science.gov (United States)

    Bedwell, Carol; McGowan, Linda; Lavender, Tina

    2015-01-01

    midwives are frequently the lead providers of care for women throughout labour and birth. In order to perform their role effectively and provide women with the choices they require midwives need to be confident in their practice. This study explores factors which may affect midwives' confidence in their practice. hermeneutic phenomenology formed the theoretical basis for the study. Prospective longitudinal data collection was completed using diaries and semi-structured interviews. Twelve midwives providing intrapartum care in a variety of settings were recruited to ensure a variety of experiences in different contexts were captured. the principal factor affecting workplace confidence, both positively and negatively, was the influence of colleagues. Perceived autonomy and a sense of familiarity could also enhance confidence. However, conflict in the workplace was a critical factor in reducing midwives' confidence. Confidence was an important, but fragile, phenomenon to midwives and they used a variety of coping strategies, emotional intelligence and presentation management to maintain it. this is the first study to highlight both the factors influencing midwives' workplace confidence and the strategies midwives employed to maintain their confidence. Confidence is important in maintaining well-being and workplace culture may play a role in explaining the current low morale within the midwifery workforce. This may have implications for women's choices and care. Support, effective leadership and education may help midwives develop and sustain a positive sense of confidence. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Time courses of intrapartum asphyxia: neonatal characteristics and outcomes.

    Science.gov (United States)

    Shah, Prakesh S; Perlman, Max

    2009-01-01

    We compared neonatal characteristics and adverse outcome rates of neonates with hypoxic-ischemic encephalopathy following (1) prolonged partial asphyxia, (2) acute near-total intrapartum asphyxia, and (3) the two combined. The time course of the insult was determined individually by two authors from obstetric data and neonatal charts. "Severe adverse outcome" was defined as death or severe disability detectable by age 2 years. The asphyxial time course was prolonged partial asphyxia in 167 (45%), acute near-total asphyxia in 96 (26%), combined in 78 (21%), and indeterminate in 34 (8%) patients. Among patients with known time course and outcomes, 212 (67%) had severe adverse outcome and 103 (33%) were free of severe adverse outcome. Severe adverse outcome rates were 61% for prolonged partial asphyxia, 67% for acute near-total asphyxia, and 79% for combined time course asphyxia ( P = 0.025). Long-term outcomes differ according to the time course of the insult; infants with combined time course had the worst outcome.

  19. Umbilical Cord Blood pH in Intrapartum Hypoxia.

    Science.gov (United States)

    Perveen, Fouzia; Khan, Ayesha; Ali, Tahmina; Rabia, Syeda

    2015-09-01

    To determine the association of cord arterial blood pH with neonatal outcome in cases of intrapartum fetal hypoxia. Descriptive analytical study. Gynaecology Unit-II, Civil Hospital, Karachi, from September 2011 to November 2012. All singleton cephalic fetuses at term gestation were included in the study. Those with any anomaly, malpresentation, medical disorders, maternal age 7.25, neonatal outcome measures (healthy, NICU admission or neonatal death), color of liquor and mode of delivery recorded on predesigned proforma. Statistical analysis performed by SPSS 16 by using independent-t test or chi-square test and ANOVA test as needed. A total of 204 newborns were evaluated. The mean pH level was found to be significantly different (p=0.007) in two groups. The pH value 7.25 had significant association (p 7.25. Majority (63.6%) cases needed caesarean section as compared to 31.4% controls. There is a significant association of cord arterial blood pH at birth with neonatal outcome at pH 7.25; but below the level of pH 7.25 it is still inconclusive.

  20. Rupture of an aneurysm of the coronary sinus of Valsalva: diagnosis by helical CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Azarine, A.; Lions, C.; Beregi, J.P. [Dept. of Vascular Surgery, Hopital Cardiologique, CHRU de Lille (France); Koussa, M. [Dept. of Vascular Radiology, Hopital Cardiologique, CHRU de Lille (France)

    2001-08-01

    A 75-year-old man presented with a 5-day history of upper chest discomfort. On auscultation, there was a systolic murmur in the left parasternal area that radiated to the apex. Electrocardiography showed flat T waves in the anterior precordial leads. Chest X ray revealed mediastinal enlargement. Transthoracic echocardiography showed a dilated proximal ascending aorta with moderate aortic regurgitation. A contrast-enhanced helical CT scan, performed to eliminate an aortic dissection, showed a ruptured left coronary sinus of Valsalva aneurysm, confirmed at surgery. This case highlights the fact that helical CT, in patients with suspected aortic dissection, may reveal other pathology that accounts for the clinical presentation. (orig.)

  1. RUPTURE OF SINUSES OF VALSALVA ANEURYSM PRESENTING AS CHRONIC HEART FAILURE - TWO CASE REPORT

    Directory of Open Access Journals (Sweden)

    Soma

    2015-11-01

    Full Text Available INTRODUCTION Ruptured sinuses of valsalva aneurysm (RSVA are a rare entity with varied clinical presentation, one of the rare complications is chronic heart failure. 1 Here we describe two cases of RSVA of right coronary sinus ruptured into right ventricle presented with features of right heart failure. CASE 1 35-year-old male with low-effort dyspnoea, nocturnal paroxysmal dyspnoea, orthopnoea, continuous murmur in left 3rd ICS, hepatomegaly and edema of the lower extremities. CASE 2 30-year-old female with dyspnoea on exertion NYHA class II-III, nocturnal paroxysmal dyspnoea, orthopnoea, diastolic murmur, congestive hepatic insufficiency, peripheral oedema diagnosed by trans thoracic Echocardiography.

  2. Manned maneuvering unit technology survey

    Science.gov (United States)

    Cook, G. V. O. (Editor)

    1975-01-01

    The preliminary design of the manned maneuvering unit (MMU) for the shuttle is investigated, and the current state of the art in certain technology areas that may find application on the operational EVA shuttle MMU is examined. Three broad areas of technology, namely: (1) mechanical energy storage - i.e., the practicality of utilizing the energy storage capability of either a reaction wheel or a control moment gyro, (2) numerical and alphanumerical displays, and (3) recent electronics developments such as microprocessors and integrated injection logic, were covered.

  3. Vagal Techniques for Terminating Paroxysmal Tachycardia in Children: Assessment of Clinical Electrophysiological Factors of Valsalva Test Effectiveness

    Directory of Open Access Journals (Sweden)

    T. K. Kruchina

    2015-01-01

    Full Text Available Background: Vagal techniques constitute the first line of medical care for terminating paroxysmal supraventricular tachycardia in children and adults due to ease of application, relative safety and possibility of avoiding injection of antiarrhythmic drugs. Effectiveness of vagal techniques depends on the method of execution, as well as a range of clinical and electrophysiological factors, which require study and specification. Objective: Our aim was to study effectiveness of the modified Valsalva test for terminating paroxysmal tachycardia in children. Methods: Effectiveness of the Valsalva test for terminating paroxysmal tachycardia induced in the course of a transesophageal electrophysiological examination in children aged 7–18 years was studied retrospectively. Results: Data of 306 children (mean age — 13.1 ± 3.2 years were analyzed; 130 of them (42.5% suffered from paroxysmal AV nodal reentrant tachycardia (PAVNRT, 176 — from paroxysmal AV reentrant tachycardia involving an additional AV connection (PAVRT. Valsalva test was effective in 88 children (28.8% — 44 children (33.8% with PAVNRT and 44 children (25.1% with PAVRT. In most cases, tachycardia was terminated by means of anterograde block: PAVRT — in 65.5% of the cases, PAVNRT — in 92.7% of the cases. Children with ineffective Valsalva test featured longer duration of the disorder (p = 0.035, higher rate of the initial sinus rhythm before a tachycardic paroxysm (p = 0.043 and higher rhythm rate during tachycardia (p = 0.019, as well as high level of AV node conduction (p = 0.038. Conclusion: Valsalva test terminates paroxysmal tachycardia in not more than 1/3 of children with paroxysmal AV reentrant tachycardia. Test effectiveness depends on duration of the disorder and electrophysiological characteristics of AV node conduction. Valsalva test is especially effective in the onset of tachycardic paroxysm and terminates it by means of anterograde AV node block in most cases. 

  4. Linking families and facilities for care at birth: What works to avert intrapartum-related deaths?

    Science.gov (United States)

    Lee, Anne CC; Lawn, Joy E.; Cousens, Simon; Kumar, Vishwajeet; Osrin, David; Bhutta, Zulfiqar A.; Wall, Steven N.; Nandakumar, Allyala K.; Syed, Uzma; Darmstadt, Gary L.

    2012-01-01

    Background Delays in receiving effective care during labor and at birth may be fatal for the mother and fetus, contributing to 2 million annual intrapartum stillbirths and intrapartum-related neonatal deaths each year. Objective We present a systematic review of strategies to link families and facilities, including community mobilization, financial incentives, emergency referral and transport systems, prenatal risk screening, and maternity waiting homes. Results There is moderate quality evidence that community mobilization with high levels of community engagement can increase institutional births and significantly reduce perinatal and early neonatal mortality. Meta-analysis showed a doubling of skilled birth attendance and a 35% reduction in early neonatal mortality. However, no data are available on intrapartum-specific outcomes. Evidence is limited, but promising, that financial incentive schemes and community referral/transport systems may increase rates of skilled birth attendance and emergency obstetric care utilization; however, impact on mortality is unknown. Current evidence for maternity waiting homes and risk screening is low quality. Conclusions Empowering communities is an important strategy to reduce the large burden of intrapartum complications. Innovations are needed to bring the poor closer to obstetric care, such as financial incentives and cell phone technology. New questions need to be asked of “old” strategies such as risk screening and maternity waiting homes. The effect of all of these strategies on maternal and perinatal mortality, particularly intrapartum-related outcomes, requires further evaluation. PMID:19815201

  5. An extracardiac unruptured right sinus of valsalva aneurysm complicated with atherothrombosis

    Directory of Open Access Journals (Sweden)

    Jun Zhang

    2016-04-01

    Full Text Available We present quite a rare case of extracardiac unruptured right sinus of valsalva aneurysm (SVA complicated with atherothrombosis in a young adult man. A 35-year-old male with a giant unruptured SVA arising from the right coronary sinus (RCS with extracardiac protrusion was diagnosed by echocardiography. Contrast-enhanced computed tomography (CT revealed a huge calcified aneurysm with mural thrombi originating from the aortic root, and about 80% stenosis at the initial segment of the right coronary artery (RCA. Intraoperative exploration demonstrated a giant unruptured aneurysm arising from the RCS. Different from other SVAs reported before, this aneurismal wall appeared thick and atheromatous-like. In this aneurysm, there was a small localized intima tearing and mural thrombosis, and the orifice of the RCA was almost blocked. This patient underwent surgical patch repair to prevent aneurysm rupture and coronary artery bypass grafting for RCA revascularization. In conclusion, the pathological examination demonstrated marked foam cells, inflammatory cells, and thrombosis in the aneurismal wall. Learning points: • Echocardiographic characteristics of sinus of valsalva aneurysm (SVA. • Diagnostic evaluation of extracardiac unruptured SVA. • Pathology of rare SVA.

  6. Anesthesia for ex utero intrapartum treatment: renewed insight on a rare procedure.

    Science.gov (United States)

    Marques, Miguel Vieira; Carneiro, João; Adriano, Marta; Lança, Filipa

    2015-01-01

    The ex utero intrapartum treatment is a rare surgical procedure performed in cases of expected postpartum fetal airway obstruction. The technique lies on a safe establishment of a patent airway during labor in anticipation of a critical respiratory event, without interrupting maternal-fetal circulation. Anesthetic management is substantially different from that regarding standard cesarean delivery and its main goals include uterine relaxation, fetal anesthesia and preservation of placental blood flow. We present the case of an ex utero intrapartum treatment procedure performed on a fetus with a large cervical lymphangioma and prenatal evidence of airway compromise. Modifications to the classic ex utero intrapartum treatment management strategies were successfully adopted and will be discussed in the following report. Copyright © 2013 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  7. [Anesthesia for ex utero intrapartum treatment: renewed insight on a rare procedure].

    Science.gov (United States)

    Marques, Miguel Vieira; Carneiro, João; Adriano, Marta; Lança, Filipa

    2015-01-01

    The ex utero intrapartum treatment is a rare surgical procedure performed in cases of expected postpartum fetal airway obstruction. The technique lies on a safe establishment of a patent airway during labor in anticipation of a critical respiratory event, without interrupting maternal-fetal circulation. Anesthetic management is substantially different from that regarding standard cesarean delivery and its main goals include uterine relaxation, fetal anesthesia and preservation of placental blood flow. We present the case of an ex utero intrapartum treatment procedure performed on a fetus with a large cervical lymphangioma and prenatal evidence of airway compromise. Modifications to the classic ex utero intrapartum treatment management strategies were successfully adopted and will be discussed in the following report. Copyright © 2013 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  8. 46 CFR 109.564 - Maneuvering characteristics.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Maneuvering characteristics. 109.564 Section 109.564 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Miscellaneous § 109.564 Maneuvering characteristics. (a) The master or person in charge of each...

  9. Neonatal morbidity associated with shoulder dystocia maneuvers.

    Science.gov (United States)

    Spain, Janine E; Frey, Heather A; Tuuli, Methodius G; Colvin, Ryan; Macones, George A; Cahill, Alison G

    2015-03-01

    We sought to examine neonatal morbidity associated with different maneuvers used among term patients who experience a shoulder dystocia. We conducted a retrospective cohort study of all women who experienced a clinically diagnosed shoulder dystocia at term requiring obstetric maneuvers at a single tertiary care hospital from 2005 through 2008. We excluded women with major fetal anomaly, intrauterine death, multiple gestation, and preterm. Women exposed to Rubin maneuver, Wood's screw maneuver, or delivery of the posterior arm were compared to women delivered by McRoberts/suprapubic pressure only, which served as the reference group. The primary outcome was a composite morbidity of neonatal injury (defined as clavicular or humeral fracture or brachial plexus injury) and neonatal depression (defined as Apgar shoulder dystocia, defined as time from delivery of fetal head to delivery of shoulders. Among the 231 women who met inclusion criteria, 135 were delivered by McRoberts/suprapubic pressure alone (57.9%), 83 women were exposed to Rubin maneuver, 53 women were exposed to Wood's screw, and 36 women were exposed to delivery of posterior arm. Individual maneuvers were not associated with composite morbidity, neonatal injury, or neonatal depression after adjusting for nulliparity and duration of shoulder dystocia. We found no association between shoulder dystocia maneuvers and neonatal morbidity after adjusting for duration, a surrogate for severity. Our results demonstrate that clinicians should utilize the maneuver most likely to result in successful delivery. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Intrapartum care could be improved according to Swedish fathers: mode of birth matters for satisfaction.

    Science.gov (United States)

    Johansson, Margareta; Hildingsson, Ingegerd

    2013-09-01

    Intrapartum care is expected to be shaped by parents' need and preferences. The aim was to explore Swedish fathers' intrapartum care quality experiences, with a specific focus on care deficiencies in relation to birth mode. A secondary aim was to explore which issues of quality that contributed most to dissatisfaction with the overall assessment of the care. Cross-sectional design, part of a prospective longitudinal survey in Sweden. A quality of care index was developed, based on perceived reality and subjective importance of given intrapartum care. Two months after birth 827 fathers answered nine questions related to quality of care. Descriptive statistics and logistic regression analysis were used. Dissatisfaction with overall intrapartum care was related to deficiencies in partner's medical care (OR 5.6; 2.7-11.2), involvement in decision-making during childbirth (OR 2.6; 1.3-4.9), midwives presence in the labour room (OR 2.4; 1.2-4.7), and ability to discuss the birth afterwards (OR 2.0; 1.1-3.8). After emergency caesarean section 46% judged the partner's medical intrapartum care as most deficient (OR 1.73; 1.05-2.86), and after elective caesarean section 40% of the fathers judged involvement in decision-making as deficient (OR 4.07; 1.95-8.50). When the fathers had participated in a spontaneous vaginal birth they were dissatisfied with the presence of the midwife in the labour room (OR 1.72; 1.03-2.87). Deficiencies existed in the intrapartum care and were judged differently depending on mode of birth. The fathers needed to feel secure about the women's medical care, and wanted to be involved and supported. Copyright © 2013 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

  11. Previous prelabor or intrapartum cesarean delivery and risk of placenta previa.

    Science.gov (United States)

    Downes, Katheryne L; Hinkle, Stefanie N; Sjaarda, Lindsey A; Albert, Paul S; Grantz, Katherine L

    2015-05-01

    The purpose of this study was to examine the association between previous cesarean delivery and subsequent placenta previa while distinguishing cesarean delivery before the onset of labor from intrapartum cesarean delivery. We conducted a retrospective cohort study of electronic medical records from 20 Utah hospitals (2002-2010) with restriction to the first 2 singleton deliveries of nulliparous women at study entry (n=26,987). First pregnancy delivery mode was classified as (1) vaginal (reference), (2) cesarean delivery before labor onset (prelabor), or (3) cesarean delivery after labor onset (intrapartum). Risk of second delivery previa was estimated by previous delivery mode with the use of logistic regression and was adjusted for maternal age, insurance, smoking, comorbidities, previous pregnancy loss, and history of previa. Most first deliveries were vaginal (82%; n=22,142), followed by intrapartum cesarean delivery (14.6%; n=3931), or prelabor cesarean delivery (3.4%; n=914). Incidence of second delivery previa was 0.29% (n=78) and differed by previous delivery mode: vaginal, 0.24%; prelabor cesarean delivery, 0.98%; intrapartum cesarean delivery, 0.38% (Pdelivery, previous prelabor cesarean delivery was associated with an increased risk of second delivery previa (adjusted odds ratio, 2.62; 95% confidence interval, 1.24-5.56). There was no significant association between previous intrapartum cesarean delivery and previa (adjusted odds ratio, 1.22; 95% confidence interval, 0.68-2.19). Previous prelabor cesarean delivery was associated with a >2-fold significantly increased risk of previa in the second delivery, although the approximately 20% increased risk of previa that was associated with previous intrapartum cesarean delivery was not significant. Although rare, the increased risk of placenta previa after previous prelabor cesarean delivery may be important when considering nonmedically indicated prelabor cesarean delivery. Published by Elsevier Inc.

  12. Prior Prelabor or Intrapartum Cesarean Delivery and Risk of Placenta Previa

    Science.gov (United States)

    Downes, Katheryne L.; Hinkle, Stefanie N.; Sjaarda, Lindsey A.; Albert, Paul S.; Grantz, Katherine L.

    2015-01-01

    Objective To examine the association between previous cesarean delivery and subsequent placenta previa while distinguishing cesarean delivery prior to onset of labor from intrapartum cesarean delivery. Study Design Retrospective cohort study of electronic medical records from 20 Utah hospitals (2002–2010) with restriction to the first two singleton deliveries of women nulliparous at study entry (n=26,987). First pregnancy delivery mode was classified as 1) vaginal (reference); 2) cesarean delivery prior to labor onset (prelabor); or 3) cesarean delivery after labor onset (intrapartum). Risk of second delivery previa was estimated by prior delivery mode using logistic regression and adjusted for maternal age, insurance, smoking, co-morbidities, prior pregnancy loss, and history of previa. Results The majority of first deliveries were vaginal (82%, n=22,142), followed by intrapartum cesarean delivery (14.6%, n=3,931), or prelabor cesarean delivery (3.4%, n=914). Incidence of second delivery previa was 0.29% (n=78) and differed by prior delivery mode: vaginal, 0.24%; prelabor cesarean delivery, 0.98%; intrapartum cesarean delivery, 0.38% (Pdelivery, prior prelabor cesarean delivery was associated with an increased risk of second delivery previa (adjusted odds ratio, 2.62 [95% confidence interval, 1.24–5.56]). There was no significant association between prior intrapartum cesarean delivery and previa [adjusted odds ratio, 1.22 (95% confidence interval, 0.68–2.19)]. Conclusion Prior prelabor cesarean delivery was associated with a more than two-fold significantly increased risk of previa in the second delivery, while the approximately 20% increased risk of previa associated with prior intrapartum cesarean delivery was not significant. Although rare, the increased risk of placenta previa after prior prelabor cesarean delivery may be important when considering non-medically indicated prelabor cesarean delivery. PMID:25576818

  13. Flight Test Maneuvers for Efficient Aerodynamic Modeling

    Science.gov (United States)

    Morelli, Eugene A.

    2011-01-01

    Novel flight test maneuvers for efficient aerodynamic modeling were developed and demonstrated in flight. Orthogonal optimized multi-sine inputs were applied to aircraft control surfaces to excite aircraft dynamic response in all six degrees of freedom simultaneously while keeping the aircraft close to chosen reference flight conditions. Each maneuver was designed for a specific modeling task that cannot be adequately or efficiently accomplished using conventional flight test maneuvers. All of the new maneuvers were first described and explained, then demonstrated on a subscale jet transport aircraft in flight. Real-time and post-flight modeling results obtained using equation-error parameter estimation in the frequency domain were used to show the effectiveness and efficiency of the new maneuvers, as well as the quality of the aerodynamic models that can be identified from the resultant flight data.

  14. Aerodynamic maneuvering hypersonic flight mechanics

    Science.gov (United States)

    Desautel, Dick

    1988-01-01

    The emergence of current high-interest mission involving aeromaneuvering hypersonic flight has given rise to the corresponding need for preliminary design and performance analyses of such vehicles. This need in turn has motivated efforts to develop simplified analytical and computational methods for parametric analysis of maneuvering hypersonic flight under conditions appropriate to the mission involved. The effort included a review of different formulations of the general equations of motion, their associated coordinate frames, various simplifications of the equations, and previously achieved analytical solutions. This study sought to both extend previous solution methods and to develop new ones. In addition, evaluation of the literature and developing a systematic perspective on the knowledge it represents proved to be a major portion of the effort.

  15. Normal values of pulmonary capillary wedge pressure and the blood pressure response to the Valsalva manoeuvre in healthy elderly subjects.

    NARCIS (Netherlands)

    Remmen, J.J.; Aengevaeren, W.R.M.; Verheugt, F.W.A.; Jansen, R.W.M.M.

    2005-01-01

    The blood pressure response to the Valsalva manoeuvre is related to pulmonary capillary wedge pressure (PCWP) and can be used to diagnose heart failure. However, this has never been studied specifically in the elderly, in whom the prevalence of heart failure is highest. Furthermore, normal values of

  16. Reimplantation valve-sparing aortic root replacement in Marfan syndrome using the Valsalva conduit: an intercontinental multicenter study.

    Science.gov (United States)

    Settepani, Fabrizio; Szeto, Wilson Y; Pacini, Davide; De Paulis, Ruggero; Chiariello, Luigi; Di Bartolomeo, Roberto; Gallotti, Roberto; Bavaria, Joseph E

    2007-02-01

    Introduced by DePaulis in 2000, the Gelweave Valsalva graft (Sulzer Vascutek, Refrewshire, Scotland) is a modified Dacron conduit (DuPont, Wilmington, DE), with prefashioned sinuses of Valsalva. The aim of this study was to evaluate the mid-term results of the reimplantation valve-sparing aortic root replacement using the Gelweave Valsalva prosthesis in Marfan syndrome patients. A retrospective review was performed of 35 patients with Marfan syndrome in four centers who underwent the reimplantation valve-sparing aortic root replacement using the Gelweave Valsalva prosthesis. The patients were predominantly men, with a mean age of 36.5 +/- 12.6 years (range, 14 to 62 years). Two patients presented with acute type A dissections and underwent emergent operations. Elective hemiarch reconstruction using hypothermic circulatory arrest was required in 11 patients. Aortic valve cusp repair was performed in 2 patients. There were no operative or hospital deaths, and no patients died during follow-up. The mean follow-up was 19 months (range, 1 to 60 months). Significant (>2+) aortic insufficiency (AI), requiring aortic valve replacement, developed in 3 patients during follow-up that requiring aortic valve replacement. The 5-year freedom from reoperation owing to structural valve deterioration was 88.9% +/- 8.1%. There were no episodes of clinically significant thromboembolism. Reimplantation valve-sparing aortic root replacement with the Gelweave Valsalva prosthesis in Marfan patients provides satisfactory mid-term results, thus encouraging further use of this type of repair. However, long-term results are needed in order to define the durability of this technique.

  17. Gigantic unruptured sinus of Valsalva aneurysm presenting as an incidental murmur.

    LENUS (Irish Health Repository)

    Yagoub, Hatim

    2012-01-01

    We report a case of a 56-year-old man referred by his family physician with an asymptomatic cardiac murmur. Trans-thoracic echocardiography (TTE) suggested an unruptured right sinus of Valsalva aneurysm (SVA) causing extrinsic compression of the right ventricular outflow tract. This was confirmed with an ECG-gated cardiac CT showing a large right SVA measuring 35×37×42 mm in size. Coronary angiography demonstrated non-obstructive coronary artery disease. Ascending thoracic anterior in the right anterior oblique view delineated the right SVA. The patient underwent aortic valve sparing surgical repair of the aneurysm with an excellent result. Echocardiography confirmed obliteration of the aneurysm and normal aortic valve function postoperatively.

  18. Intrapartum-related birth asphyxia in South Africa lessons From the ...

    African Journals Online (AJOL)

    Background. The recent amalgamation of data by users of the Perinatal Problem Identification Programme (PPIP) throughout South Africa has culminated in the publication of the Saving Babies report. Objectives. To determine the absolute rate of death from intrapartum-related birth asphyxia, and the contribution of ...

  19. Excess weight loss in first-born breastfed newborns relates to maternal intrapartum fluid balance.

    Science.gov (United States)

    Chantry, Caroline J; Nommsen-Rivers, Laurie A; Peerson, Janet M; Cohen, Roberta J; Dewey, Kathryn G

    2011-01-01

    The objectives were to describe weight loss in a multiethnic population of first-born, predominantly breastfed, term infants and to identify potentially modifiable risk factors for excess weight loss (EWL). Data on prenatal breastfeeding intentions, demographic characteristics, labor and delivery interventions and outcomes, breastfeeding behaviors, formula and pacifier use, onset of lactogenesis, and nipple type and pain were collected prospectively. Logistic regression analyses identified independent predictors of EWL (≥10% of birth weight) by using a preplanned theoretical model. EWL occurred for 18% of infants who received no or minimal (≤60 mL total since birth) formula (n = 229), including 19% of exclusively breastfed infants (n = 134) and 16% of infants who received minimal formula (n = 95). In bivariate analyses, EWL was associated (P lactogenesis (>72 hours), fewer infant stools, and infant birth weight. In multivariate logistic regression analysis, only 2 variables predicted EWL significantly, namely, intrapartum fluid balance (adjusted relative risk for EWL of 3.18 [95% confidence interval [CI]: 1.35-13.29] and 2.80 [95% CI: 1.17-11.68] with net intrapartum fluid balance of >200 and 100-200 mL/hour, respectively, compared with lactogenesis (adjusted relative risk: 3.35 [95% CI: 1.74-8.10]). EWL was more common in this population than reported previously and was independently related to intrapartum fluid balance. This suggests that intrapartum fluid administration can cause fetal volume expansion and greater fluid loss after birth, although other mechanisms are possible.

  20. Intrapartum fetal monitoring by ST-analysis of the fetal ECG

    NARCIS (Netherlands)

    Westerhuis, M.E.M.H.

    2010-01-01

    Objective Intrapartum fetal monitoring aims to identify fetuses at risk for neonatal and long-term injury due to asphyxia. To serve this purpose, cardiotocography (CTG) combined with ST-analysis of the fetal electrocardiogram (ECG), which is a relatively new method, may be used. The main aim of this

  1. The effect of short-term isometric muscle contraction and the Valsalva maneuver on systemic and pulmonary hemodynamics in patients with severe heart failure

    Czech Academy of Sciences Publication Activity Database

    Souček, M.; Fráňa, P.; Kára, J.; Sitar, J.; Halámek, Josef; Jurák, Pavel; Řiháček, I.; Špinarová, L.; Oral, I.

    2009-01-01

    Roč. 32, č. 6 (2009), E32-E39 ISSN 0160-9289 R&D Projects: GA ČR(CZ) GA102/05/0402 Institutional research plan: CEZ:AV0Z20650511 Keywords : leg muscle * muscle isometric contraction Subject RIV: FS - Medical Facilities ; Equipment Impact factor: 1.602, year: 2009

  2. Aneurisma do seio de Valsalva: análise de sete casos Aneurysm of the sinus of Valsalva: analysis of seven cases

    Directory of Open Access Journals (Sweden)

    Ricardo M Mustafá

    1991-04-01

    Full Text Available Os autores apresentam a experiência acumulada de janeiro de 1984 a julho de 1990, no Instituto de Moléstias Cardiovasculares (IMC, de sete casos de aneurisma do seio de Valsalva (ASV, tratados cirurgicamente com uso de retalho de pericárdio bovino (PB, ou troca valvar nos casos indicados. Cinco casos eram de origem congênita e dois estavam associados a doença reumática. Dos congênitos, quatro estavam rotos, sendo dois para o átrio direito e dois para o ventrículo direito; em um caso não havia rotura e se projetava para o ventrículo esquerdo. Dos dois casos associados a doença reumática, um estava roto para o ventrículo direito e o outro apresentava protrusão do saco aneurismático para o ventrículo esquerdo e eversão da válvula aórtica correspondente. Foi usado retalho de PB para dar sustentação à sutura nos casos de ASV congênitos; destes, um evoluiu com deiscência da sutura aos sete meses e aos seis anos, sendo reoperado nas duas ocasiões. Nos casos associados a doença reumática, foi realizada a substituição valvar com prótese biológica PB IMC; dos dois pacientes, um foi a óbito, em decorrência de acidente vascular cerebral, no 15º dia de pós-operatório. Conclui-se que, quando não há alterações secundárias nas válvulas (ex.: calcificação, endocardite, etc, a restauração é possível e desejada, com boa evolução quando se usa retralho de pericárdio bovino.The authors present their experience on seven cases of Valsalva-sinus aneurysm (VSA at the Instituto de Moléstias Cardiovasculares (IMC, from January 1984 to July 1990, treated surgically using bovine pericardium patch (PB-IMC or valve replacement when indicated. Five cases were congenital and two were related to rheumatic disease. In two of the congenital cases the aneurysms were leaking into the right atrium, two were leaking into the right ventricle. And the remaining one was not leaking but was projected into the left ventricle. One of the

  3. 32 CFR 644.137 - Maneuver agreements.

    Science.gov (United States)

    2010-07-01

    ... camp sites, field hospital sites and supply dumps), and buildings needed for warehouses, ordnance shops... the Chief of Engineers upon receipt of a specific request from the using command to acquire maneuver...

  4. Synthetic Imaging Maneuver Optimization (SIMO) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aurora Flight Sciences (AFS), in collaboration with the MIT Space Systems Laboratory (MIT-SSL), proposed the Synthetic Imaging Maneuver Optimization (SIMO) program...

  5. Automated Robust Maneuver Design and Optimization

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA is seeking improvements to the current technologies related to Position, Navigation and Timing. In particular, it is desired to automate precise maneuver...

  6. The association of maternal intrapartum subfebrile temperature and adverse obstetric and neonatal outcomes.

    Science.gov (United States)

    Dior, Uri P; Kogan, Liron; Calderon-Margalit, Ronit; Burger, Ayala; Amsallem, Hagai; Elchalal, Uriel; Eventov-Friedman, Smadar; Ergaz, Zivanit; Ezra, Yossef

    2014-01-01

    Subfebrile intrapartum maternal temperature is very common, yet there is sparse evidence regarding its causes or its effects on perinatal outcomes. We examined whether mild temperature elevation during labour is a risk marker for adverse obstetric and neonatal outcomes. A retrospective cohort analysis including 42 601 term, singleton live-births in two medical centres between 2003 and 2010 was performed. This study compared women who experienced a maximal intrapartum temperature of ≤37°C with women who experienced subfebrile intrapartum temperature (37.1-37.9°C). Adjusted risks for adverse obstetric and neonatal outcomes were calculated by using multivariable logistic regression models. Compared with maternal temperature ≤ 37°C, subfebrile temperature was associated with higher rates of primary caesarean deliveries {adjusted odds ratios [aOR] = 1.36 [95% confidence interval (CI) 1.25, 1.49])} and assisted vaginal deliveries (aOR = 1.20 [95% CI 1.11, 1.30]), as well as with greater risks of early neonatal sepsis (aOR = 2.66 [95% CI 1.88, 3.77]), neonatal intensive care unit admissions (aOR = 1.40 [95% CI 1.08, 1.83]), and neonatal asphyxia or seizures (aOR = 3.18 [95% CI 1.51, 6.70]). Mildly elevated maternal intrapartum temperature (37.1-37.5°C) was also associated with adverse outcomes. Maternal intrapartum subfebrile temperature may be an indicator of operative delivery and neonatal morbidity. Further research is needed to confirm these findings and to reveal underlying mechanisms. © 2013 John Wiley & Sons Ltd.

  7. Do recruitment maneuvers simply improve oxygenation?

    OpenAIRE

    Valenza, Franco

    2010-01-01

    Recruitment maneuvers have been the subject of intense investigation. Their role in the acute care setting is debated given the lack of information on their influence on clinical outcomes. Oxygenation improvement is often a striking effect, together with changes of respiratory mechanics. However, hemodynamic compromise is frequently associated with the maneuver, sometimes even barotrauma. Another possible downside is bacterial translocation secondary to lung overdistention, as suggested by ex...

  8. 14 CFR 23.337 - Limit maneuvering load factors.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factors. 23.337... Flight Loads § 23.337 Limit maneuvering load factors. (a) The positive limit maneuvering load factor n... airplanes; or (3) 6.0 for acrobatic category airplanes. (b) The negative limit maneuvering load factor may...

  9. Correção cirúrgica do aneurisma roto do seio de Valsalva: relato de dois casos Surgical repair of ruptured sinus of Valsalva aneurysms: report of two cases

    Directory of Open Access Journals (Sweden)

    Lourival BONATELLI FILHO

    1999-10-01

    Full Text Available O objetivo deste estudo é relatar a técnica cirúrgica empregada na correção de aneurisma do seio de Valsalva roto para dentro do ventrículo direito, em 2 pacientes adultos, tendo um deles, concomitantemente, leve coarctação da aorta. No primeiro caso, mulher de 22 anos com dispnéia progressiva, cuja avaliação ecocardiográfica revelou rotura do aneurisma do seio de Valsalva para dentro do ventrículo direito e coarctação da aorta leve, com gradiente de 25 mmHg. O cateterismo cardíaco confirmou o diagnóstico. No segundo caso, homem de 35 anos, com piora de dispnéia há 2 meses. Ecocardiograma e cateterismo cardíaco confirmaram o diagnóstico de aneurisma roto do seio de Valsalva para o ventrículo direito. Ambos foram operados através de esternotomia mediana; circulação extracorpórea convencional e cardioplegia sangüínea fria. No primeiro caso a valva aórtica era bivalvulada, com o aneurisma do seio de Valsalva anterior, relacionado à coronária direita, roto para dentro do VD, medindo 6 mm de diâmetro, foi fechado com sutura direta com fio 5-0. No segundo caso a valva aórtica era trivalvulada e o aneurisma do seio de Valsalva direito que rompeu, também, dentro do VD, media 12 mm de diâmetro e o fechamento foi feito com retalho de pericárdio bovino, suturado com pontos separados de polipropileno 5-0. Ambos os pacientes tiveram evolução pós-operatória sem intercorrências. Alta hospitalar ao final de uma semana. No controle ambulatorial, 120 e 60 dias após, respectivamente, estavam assintomáticos.The purpose of this article is to report the surgical treatment of ruptured sinus of Valsalva aneurysms in two patients. First case was a young woman whose aneurysm originated in the right sinus and entered the right ventricle, besides a mild coarctation of the aorta. Surgical repair was carried out using cardiopulmonary bypass with moderate hypothermia. After aortotomy the ruptured sinus of Valsalva was directly closed

  10. CT and MR in aneurysm of the sinus of Valsalva diagnosis: two cases. TC y RM en el diagnostico del aneurisma del seno de Valsalva: a proposito de dos casos

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Granda Fernandez, F.; Navarro Sanchis, E.; Valdes Solis, P.; Sanchez-Lafuente, J.; Rodriguez San Pedro, F.

    1994-01-01

    We report two cases of aneurysm of the sinus of Valsalva that appeared as mediastinal masses having no related symptomatology. CT and MR studies were carried out in both cases. The assessment of the findings obtained with these two imaging methods led to the diagnosis, which was later confirmed by means of angiocardiography in one case and after surgery in the other. (Author) 19 refs.

  11. [Ruptured Aneurysm of the Sinus of Valsalva Accompanied with a Bicuspid Aortic Valve in an Elderly Man;Report of a Case].

    Science.gov (United States)

    Murase, Toshifumi; Tamura, Susumu; Ohzeki, Yasuhiro; Ebine, Kunio

    2017-09-01

    The combination of ruptured aneurysm of the sinus of Valsalva and a bicuspid aortic valve is very rare in an elderly person. A 71-year-old man with ruptured aneurysm of the sinus of Valsalva and a bicuspid aortic valve had undergone an operation. He was admitted to his other hospital because of heart failure. He was transferred to our hospital to undergo treatment for ruptured aneurysm of sinus of Valsalva. At our hospital, echocardiography findings showed ruptured aneurysm of the sinus of Valsalva, a ventricular septal defect (VSD), and severe aortic regurgitation with moderate stenosis of the bicuspid aortic valve. An aneurysm originating from the anterior sinus of Valsalva had ruptured into the right ventricular outflow tract. The ruptured aneurysm and VSD were repaired by patch closure through the right ventricular outflow tract. Additionally, the aneurysm of the sinus of Valsalva was repaired with direct closure through aortotomy. The insufficient bicuspid aortic valve was replaced with a bioprosthetic valve. After the operation, heart failure improved promptly, and he was making satisfactory progress in his recovery.

  12. Interatrial rupture of a non-coronary sinus of Valsalva aneurysm: a rare presentation of a rare disorder.

    Science.gov (United States)

    Mwambingu, Thomas L; Matthews, Iain G; Thambyrajah, Jeet; Andrew Owens, W

    2011-12-01

    A 65-year-old male was referred to our team after the incidental finding of a large non-coronary sinus of Valsalva aneurysm on computed tomography (CT)-scan of the thorax. Further imaging with transesophageal echocardiography (TOE) excluded intracardiac shunting. Unusually, the aneurysm had ruptured into the interatrial septum and was seen to be compressing both atria. At operative intervention, a 20 mm defect which had replaced the non-coronary sinus was repaired using a patch graft. An aneurysm of an aortic sinus is a rare disorder, and a rupture of a non-coronary sinus typically results in the formation of a fistulous tract in the right atrium. These images highlight an unusual case of a non-coronary sinus of Valsalva aneurysm which ruptured into the interatrial septum (IAS), and demonstrate the benefit of multi-modality cardiac imaging in guiding surgical repair.

  13. Unruptured aneurysm of the left sinus of Valsalva compressing the left main coronary artery: successful percutaneous treatment.

    Science.gov (United States)

    Hausinger, P; Sasi, V; Volford, G; Bitay, M; Bogáts, G; Thury, A; Palkó, A; Forster, T; Nemes, A

    2014-09-01

    Aneurysm of the left sinus of Valsalva is an extremely rare entity. It may be asymptomatic and incidentally discovered, or may be symptomatic and manifest acutely with compression of adjacent cardiac structures. Encasement of the left main coronary artery by such an aneurysm is a recognized but infrequent complication that can lead to severe coronary insufficiency. Surgical decompression of the left main coronary artery is the standard treatment for such conditions. We describe a patient presenting with extrinsic compression of the left main coronary artery by a large unruptured aneurysm of the left sinus of Valsalva occurring 4 months after unsuccessful surgical repair. Since reoperation was considered high-risk for the patient, successful fractional flow reserve- and intravascular ultrasound-guided percutaneous treatment of the left main coronary artery was performed with implantation of one bare-metal stent.

  14. Improved Maneuver Reconstructions for the GRAIL Orbiters

    Science.gov (United States)

    Keck, Mason; You, Tung-Han; Antreasian, Peter

    2012-01-01

    Maneuver reconstructions for the Gravity Recovery and Interior Laboratory (GRAIL) A and B lunar orbiters were improved through updates to the orbit determination filter and dynamic models. Consistent reconstructions of the 27 GRAIL A and B maneuvers from the Trans-Lunar Cruise phase in the fall of 2011 through the Transition to Science Formation phase in February 2012 were performed. Standard methods of orbit determination were applied incorporating the latest dynamic models and filter strategies developed by the GRAIL Navigation and Science Teams, including a high resolution, 420 x 420 degree and order lunar spherical harmonic gravity field model. For Trans-Lunar Cruise for GRAIL-A (TLC-A), all maneuvers executed with delta V errors below 5.50 +/- 0.50 mm/s and pointing errors below 0.25 degrees. GRAIL-A lunar orbit maneuvers had delta V errors below 30.0 mm/s and pointing errors below 0.51 degrees. For TLC-B, all maneuvers executed with delta V errors below 8.60 +/- 1.41 mm/s and pointing errors below 0.300 degrees. GRAIL-B maneuvers in lunar orbit executed with maximum delta V errors of 25.0 mm/s and pointing error of 0.43 degrees. These maneuver reconstructions will enable the GRAIL Navigation Team to better characterize the main engine performance of each spacecraft. This will help the Navigation Team to navigate low (greater than 8 km) altitude orbits during the extended mission phase in the fall of 2012.

  15. Factors associated with women's perception of and satisfaction with quality of intrapartum care practices in Swaziland.

    Science.gov (United States)

    Gamedze-Mshayisa, Dumsile Innocentia; Kuo, Su-Chen; Liu, Chieh-Yu; Lu, Yu-Ying

    2018-02-01

    giving birth is a lifetime event, where the quality of care a woman receives has the potential to affect her or her baby both physically and emotionally either on a short-term or long-term basis. This study aimed at identifying factors associated with women's perception of and satisfaction with the quality of intrapartum care as well as their future loyalty intentions in two regional hospitals in Swaziland. this is a correlational study where data were collected from 383 women conveniently selected from two regional hospitals where they gave birth. The QPP-I, SHPC, AND WOM questionnaires were used for data collection which was done from July to September 2016. the results reflected that women's satisfaction with quality of intrapartum care total mean score was (M±SD = 74.17±10.1), a perceived reality of intrapartum care practices total mean score of (M±SD = 96.94±16.0), a high subjective importance total mean score (M±SD = 117.78±10.5), and above average future loyalty intension total mean score (M±SD 1.67±0.69). Factors that significantly predicted women's satisfaction with quality of intrapartum care include, perceived quality (F = 54.13, p<0.001 with 28% R 2 variance), demographic variables (educational level, employment status and gestational weeks) (F = 10.66, p =<0.001, with 8% R 2 variance), future loyalty intensions (F = 48.57, p<0.001with 7% R 2 variance), and subjective importance (F = 44.74, p<0.001 with 1% R 2 variance). the study revealed that women's perceived reality of and satisfaction with the quality of intrapartum care practices was suboptimal. Improvement should be focused on evidence-based intrapartum care that is women-centered, involving the clients in decision-making and also a comprehensive childbirth education for the pregnant mothers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Women's satisfaction with intrapartum care in St Paul's Hospital Millennium Medical College Addis Ababa Ethiopia: a cross sectional study.

    Science.gov (United States)

    Demas, Tangute; Getinet, Tewodros; Bekele, Delayehu; Gishu, Teshome; Birara, Malede; Abeje, Yemesrach

    2017-07-28

    Satisfaction during intrapartum care is the most influential attribute on maternal health service return behaviors and utilization. Measuring satisfaction of women with intrapartum care helps to address the problems and improves the quality of delivery services. The aim of this study is to assess women's level of satisfaction during intrapartum care. A hospital based, analytic, cross sectional study was conducted at St. Paul's Hospital Millennium Medical College (SPHMMC), Addis Ababa Ethiopia, from May to June 2015. Data collectors administered a structured and pretested questionnaire to collect data and then analyzed it using SPSS version 20.0 software. Binary logistic regression was used to identify factors associated with women's intrapartum care satisfaction. A total of 394 women of mean age 25.98 years with a standard deviation of ±4.72were included in the study. Only 19% of the women were satisfied with the intrapartum care they received. The variables which were significantly associated with satisfaction of intrapartum care were; opportunity to talk Adjusted Odds Ratio (AOR) (95% CI) 2.44 (1.12, 5.29); Pain Management AOR (95% CI) 3.37 (1.83, 6.21); Short Length of Time Taken for Admission After Seen by Health Professionals AOR (95% CI)0 .97 (0.93, 0.99), and Short Length of Stay in the Hospital AOR (95% CI) 0.91 (0.87, 0.96). The women's overall satisfaction with intrapartum care was low. Multiple factors influence their satisfaction. Health professionals, policy makers and health administrators should give emphasis to factors that contribute to low satisfaction of women with intrapartum care. They should also strengthen their efforts to deliver quality and easily accessible maternal health service to improve women's overall satisfaction with the maternal health service.

  17. Intrapartum fetal heart rate classification from trajectory in Sparse SVM feature space.

    Science.gov (United States)

    Spilka, J; Frecon, J; Leonarduzzi, R; Pustelnik, N; Abry, P; Doret, M

    2015-01-01

    Intrapartum fetal heart rate (FHR) constitutes a prominent source of information for the assessment of fetal reactions to stress events during delivery. Yet, early detection of fetal acidosis remains a challenging signal processing task. The originality of the present contribution are three-fold: multiscale representations and wavelet leader based multifractal analysis are used to quantify FHR variability ; Supervised classification is achieved by means of Sparse-SVM that aim jointly to achieve optimal detection performance and to select relevant features in a multivariate setting ; Trajectories in the feature space accounting for the evolution along time of features while labor progresses are involved in the construction of indices quantifying fetal health. The classification performance permitted by this combination of tools are quantified on a intrapartum FHR large database (≃ 1250 subjects) collected at a French academic public hospital.

  18. The "Bermuda triangle" of neonatal neurology: cerebral palsy, neonatal encephalopathy, and intrapartum asphyxia.

    Science.gov (United States)

    Shevell, Michael I

    2004-03-01

    The terms "cerebral palsy," "neonatal encephalopathy," and "intrapartum asphyxia" are frequently used in pediatric neurology. This article presents concise, verifiable definitions for each of these entities based on our current understanding and formulates the nature of the interrelationships between them. The aim is to provide a level of clarity that will enhance diagnostic and pathogenetic precision and minimize conceptual misunderstanding. This should aid future therapeutic and research efforts in this important area.

  19. Intrapartum Temperature Elevation, Epidural Use, and Adverse Outcome in Term Infants

    Science.gov (United States)

    Wyshak, Grace; Ringer, Steven A.; Johnson, Lise C.; Rivkin, Michael J.; Lieberman, Ellice

    2012-01-01

    OBJECTIVES: To examine the association of intrapartum temperature elevation with adverse neonatal outcome among low-risk women receiving epidural analgesia and evaluate the association of epidural with adverse neonatal outcome without temperature elevation. METHODS: We studied all low-risk nulliparous women with singleton pregnancies ≥37 weeks delivering at our hospital during 2000, excluding pregnancies where infants had documented sepsis, meningitis, or a major congenital anomaly. Neonatal outcomes were compared between women receiving (n = 1538) and not receiving epidural analgesia (n = 363) in the absence of intrapartum temperature elevation (≤99.5°F) and according to the level of intrapartum temperature elevation within the group receiving epidural (n = 2784). Logistic regression was used to evaluate neonatal outcome while controlling for confounders. RESULTS: Maternal temperature >100.4°F developed during labor in 19.2% (535/2784) of women receiving epidural compared with 2.4% (10/425) not receiving epidural. In the absence of intrapartum temperature elevation (≤99.5°F), no significant differences were observed in adverse neonatal outcomes between women receiving and not receiving epidural. Among women receiving epidural, a significant linear trend was observed between maximum maternal temperature and all neonatal outcomes examined including hypotonia, assisted ventilation, 1- and 5-min Apgar scores 101°F had a two- to sixfold increased risk of all adverse outcomes examined. CONCLUSIONS: The proportion of infants experiencing adverse outcomes increased with the degree of epidural-related maternal temperature elevation. Epidural use without temperature elevation was not associated with any of the adverse outcomes we studied. PMID:22291120

  20. Nd:YAG laser hyaloidotomy for valsalva pre-macular haemorrhage.

    LENUS (Irish Health Repository)

    Kirwan, R P

    2012-02-01

    AIM: To report a case of successful drainage of a large pre-macular haemorrhage using laser photo-disruption of the posterior hyaloid membrane. MATERIALS AND METHODS: A case report. RESULTS: A 47-year-old man presented acutely to our emergency department complaining of a 24-h history of sudden onset, painless and persistent loss of vision in his left eye. Immediately before noticing this loss of vision, he had been vomiting violently from excessive alcohol intake. The left visual acuity was counting fingers. Dilated fundoscopy of the left eye revealed a large pre-macular haemorrhage which was 14 disc diametres in size. Clotting investigations were normal. A diagnosis of valsalva retinopathy was made and the patient elected to receive a prompt neodymium-doped yttrium aluminium garnet (Nd:YAG) laser posterior hyaloidotomy as an outpatient. At 1 week follow-up, the haemorrhage had drained completely into the vitreous space revealing a healthy macula and the visual acuity had improved to 6\\/12 unaided. At 6-month follow-up the left visual acuity stabilised at 6\\/9 unaided. CONCLUSION: Nd:YAG laser posterior hyaloidotomy is a useful outpatient procedure for successful clearance of large pre-macular haemorrhages that offers patients rapid recovery of visual acuity and the avoidance of more invasive intraocular surgery.

  1. Management of supraventricular tachycardia using the Valsalva manoeuvre: a historical review and summary of published evidence.

    Science.gov (United States)

    Smith, Gavin

    2012-12-01

    Use of the Valsalva manoeuvre (VM) as a first-line management tool for the reversion of supraventricular tachycardia (SVT) in both emergency medicine and prehospital emergency-care settings has presented challenges, requiring continuous examination and refinement to define both its appropriateness and effectiveness. This report details the evolution of knowledge related to SVT and the historical evolution and controversies associated with VM; it also highlights the ongoing development of an evidence-based model of practice for the management of SVT in the emergency medicine and prehospital emergency-care settings. A two-part review of the literature using electronic medical databases was conducted. Other relevant texts or articles unavailable within the electronic search were also identified. Part 1 of the search criteria identified the historical evolution of the pathophysiology of SVT, whereas part 2 identified the use of VM for the clinical management of SVT. Part 1 of the review identified a total of 38 articles with eight meeting the inclusion criteria, and part 2 of the review identified a total of 44 articles with 17 meeting the inclusion criteria. An evidence-based model of practice requires clarification. The differentiation of nodal re-entrant tachycardias may, with further research, lead to identification of the specificity of VM in reversion of SVT during the early stages of arrhythmia. There is a need for further prehospital and emergency department research to quantify an evidence-based approach to VM.

  2. Predicting intrapartum fetal compromise using the fetal cerebro-umbilical ratio.

    Science.gov (United States)

    Sabdia, S; Greer, R M; Prior, T; Kumar, S

    2015-05-01

    The aim of this study was to explore the association between the cerebro-umbilical ratio measured at 35-37 weeks and intrapartum fetal compromise. This retrospective cross sectional study was conducted at the Mater Mothers' Hospital in Brisbane, Australia. Maternal demographics and fetal Doppler indices at 35-37 weeks gestation for 1381 women were correlated with intrapartum and neonatal outcomes. Babies born by caesarean section or instrumental delivery for fetal compromise had the lowest median cerebro-umbilical ratio 1.60 (IQR 1.22-2.08) compared to all other delivery groups (vaginal delivery, emergency delivery for failure to progress, emergency caesarean section for other reasons or elective caesarean section). The percentage of infants with a cerebro-umbilical ratio cerebro-umbilical ratio between the 10th-90th centile and 9.6% of infants with a cerebro-umbilical ratio > 90th centile required delivery for the same indication (p cerebro-umbilical ratio was associated with an increased risk of emergency delivery for fetal compromise, OR 2.03 (95% CI 1.41-2.92), p cerebro-umbilical ratio measured at 35-37 weeks is associated with a greater risk of intrapartum compromise. This is a relatively simple technique which could be used to risk stratify women in diverse healthcare settings. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Unifying psychology: epistemological act or disciplinary maneuver?

    Science.gov (United States)

    Stam, Henderikus J

    2004-12-01

    Two arguments with attempts to unify psychology are adumbrated in this commentary. First, the unification of psychology is largely a disciplinary maneuver and not primarily an epistemological act. Second, the discipline of psychology has been unified for some time around a series of methodological and functional categories that have served to support its institutional projects but hide metaphysical problems. 2004 Wiley Periodicals, Inc.

  4. Detect and Avoid (DAA) Automation Maneuver Study

    Science.gov (United States)

    2017-02-01

    controlled a UAS through airspace including several proximal aircraft. 15. SUBJECT TERMS Drones ; Detect and Avoid; Remotely Piloted Aircraft...maneuver guidance presentation but the transparency “threshold” needed to result in appropriate automation usage , which is defined as both high rates of

  5. Optimizing interplanetary trajectories with deep space maneuvers

    Science.gov (United States)

    Navagh, John

    1993-09-01

    Analysis of interplanetary trajectories is a crucial area for both manned and unmanned missions of the Space Exploration Initiative. A deep space maneuver (DSM) can improve a trajectory in much the same way as a planetary swingby. However, instead of using a gravitational field to alter the trajectory, the on-board propulsion system of the spacecraft is used when the vehicle is not near a planet. The purpose is to develop an algorithm to determine where and when to use deep space maneuvers to reduce the cost of a trajectory. The approach taken to solve this problem uses primer vector theory in combination with a non-linear optimizing program to minimize Delta(V). A set of necessary conditions on the primer vector is shown to indicate whether a deep space maneuver will be beneficial. Deep space maneuvers are applied to a round trip mission to Mars to determine their effect on the launch opportunities. Other studies which were performed include cycler trajectories and Mars mission abort scenarios. It was found that the software developed was able to locate quickly DSM's which lower the total Delta(V) on these trajectories.

  6. About avatars and maneuvering in virtual environments

    NARCIS (Netherlands)

    Delleman, N.

    2006-01-01

    This paper is about the use of avatars and maneuvering in virtual environments for simulation-based design ergonomics. An avatar is a digital human model driven by an instrumented human who is immersed in a virtual environment. A presentation on locomotion devices is followed by descriptions of

  7. 14 CFR 25.337 - Limit maneuvering load factors.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factors. 25.337... Conditions § 25.337 Limit maneuvering load factors. (a) Except where limited by maximum (static) lift... maneuvering load factors prescribed in this section. Pitching velocities appropriate to the corresponding pull...

  8. 14 CFR 23.1507 - Operating maneuvering speed.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Operating maneuvering speed. 23.1507... Limitations and Information § 23.1507 Operating maneuvering speed. The maximum operating maneuvering speed, VO, must be established as an operating limitation. VO is a selected speed that is not greater than VS√n...

  9. Can facility delivery reduce the risk of intrapartum complications-related perinatal mortality? Findings from a cohort study.

    Science.gov (United States)

    Khanam, Rasheda; Baqui, Abdullah H; Syed, Mamun Ibne Moin; Harrison, Meagan; Begum, Nazma; Quaiyum, Abdul; Saha, Samir K; Ahmed, Saifuddin

    2018-06-01

    Intrapartum complications increase the risk of perinatal deaths. However, population-based data from developing countries assessing the contribution of intrapartum complications to perinatal deaths is scarce. Using data from a cohort of pregnant women followed between 2011 and 2013 in Bangladesh, this study examined the rate and types of intrapartum complications, the association of intrapartum complications with perinatal mortality, and if facility delivery modified the risk of intrapartum-related perinatal deaths. Trained community health workers (CHWs) made two-monthly home visits to identify pregnant women, visited them twice during pregnancy and 10 times in the first two months postpartum. During prenatal visits, CHWs collected data on women's prior obstetric history, socio-demographic status, and complications during pregnancy. They collected data on intrapartum complications, delivery care, and pregnancy outcome during the first postnatal visit within 7 days of delivery. We examined the association of intrapartum complications and facility delivery with perinatal mortality by estimating odds ratios (OR) and 95% confidence intervals (CI) adjusting for covariates using multivariable logistic regression analysis. The overall facility delivery rate was low (3922/24 271; 16.2%). Any intrapartum complications among pregnant women were 20.9% (5,061/24,271) and perinatal mortality was 64.7 per 1000 birth. Compared to women who delivered at home, the risk of perinatal mortality was 2.4 times higher (OR = 2.40; 95% CI = 2.08-2.76) when delivered in a public health facility and 1.3 times higher (OR = 1.32, 95% CI = 1.06-1.64) when delivered in a private health facility. Compared to women who had no intrapartum complications and delivered at home, women with intrapartum complications who delivered at home had a substantially higher risk of perinatal mortality (OR = 3.45; 95% CI = 3.04-3.91). Compared to women with intrapartum complications who

  10. Reimplantation valve-sparing aortic root replacement with the Valsalva graft: what have we learnt after 100 cases?

    Science.gov (United States)

    Settepani, Fabrizio; Bergonzini, Marcello; Barbone, Alessandro; Citterio, Enrico; Basciu, Alessio; Ornaghi, Diego; Gallotti, Roberto; Tarelli, Giuseppe

    2009-07-01

    Reimplantation valve-sparing aortic root replacement has been increasingly performed with improving perioperative and mid-term results. The success of this operation primarily depends on preserving the highly sophisticated dynamic function of the aortic valve by recreating an anatomical three-dimensional configuration similar to the normal aortic root, thus minimizing the mechanical stress and strain on the cusps. Over the years several techniques have been proposed to reproduce the sinuses of Valsalva. We reviewed our experience with aortic valve reimplantation by means of a modified Dacron graft that incorporates sinuses of Valsalva, in a series of 100 consecutive patients. During a 60-month period, 100 patients with aortic root aneurysm underwent aortic valve reimplantation using the Gelweave Valsalva prosthesis. There were 74 males and the mean age was 60+/-12 years (range 28-83 years). Five patients had the Marfan's syndrome, 15 had a bicuspid aortic valve. Cusp repair was performed in five patients. The mean follow-up time was 28.6 months (range 1-60). Transesophageal echocardiogram was performed at the end of each procedure to assess the aortic valve in terms of competence, dynamic motion and level of coaptation within the graft. There was one hospital death and two late deaths. Overall survival at 60 months was 91.7+/-5.1%. Five patients developed severe aortic incompetence (AI) during follow-up requiring aortic valve replacement (AVR). The 60 months freedom from re-operation due to AI was 90.9+/-4.4%. One patient had moderate AI at latest echocardiographic study. The 60 months freedom from AI>2+ was 91.6+/-7.9%. Cox regression identified cusp's repair as independent risk factor (P=0.001) for late reimplantation failure (AVR or AI>2+). There were no episodes of endocarditis and the majority of the patients (88%) were in New York Heart Association functional class I. The aortic valve reimplantation with the Gelweave Valsalva prosthesis provided satisfactory

  11. Late Diagnosis of Anomalous Aortic Origin of a Coronary Artery from the Inappropriate Sinus of Valsalva during Investigation of Chest Pain

    Directory of Open Access Journals (Sweden)

    Brunna Priscylla Américo Carvalho

    2018-01-01

    Full Text Available In this work are reported two cases of anomalous aortic origin of a coronary artery (AAOCA, with the left main coronary artery (LMCA arising at the right sinus of Valsalva in a 77-year-old woman and in a 79-year-old man submitted to angiography after positive ischemic tests. The origin of the LMCA or the left descendant artery (LDA from the right sinus of Valsalva has a prevalence of 0.2%, the origin of the circumflex artery (CXA from the right sinus 0.5%, and the origin of the right coronary artery (RCA from the left sinus of Valsalva has a prevalence of 0.3%. It is the subgroup of the coronary anomalies that has the greatest potential for clinical repercussions, especially the sudden cardiac death (SCD. We discuss the diagnostic methods and treatment options for this kind of coronary anomaly in symptomatic cases.

  12. Vibration Characteristics of Squeeze Film Damper during Maneuver Flight

    Science.gov (United States)

    Wang, Siji; Liao, Mingfu; Li, Wei

    2015-05-01

    The rotor systems of an aero engine will endure additional centrifugal force and gyroscopic moment during maneuver flight. A maneuver fly mechanical simulator is designed and experimental investigations on dynamics of squeeze film damper (SFD) under the different additional centrifugal force and gyroscopic moment are carried out. The results show that the maneuver flight weaken effectiveness of the SFD, the additional centrifugal force and gyroscopic moment caused by maneuver flight will change film damping, film stiffness. And the influence of maneuver flight can be effective relieved by increasing the film clearance.

  13. Outcome Assessment of the Marshall Coughing Test during Cervix Reposition Maneuver in Women with Urinary Stress Incontinence with/without Genital Prolapse.

    Science.gov (United States)

    Antovska, Vesna

    2012-01-01

    Objectives. Outcome assessment of the Marshall coughing test (MT) during cervix reposition maneuver (CRM) in women with urinary stress incontinence (USI) with/without genital prolapse (GP). Study Design. 268 patients, divided into USIg (n = 132) with isolated USI and USIGPg (n = 136) with USI and GP stage I/II, additionally divided into USIGP(A) (n = 78) with USI and GP stage I and USIGP(B) (n = 58) with USI and GP stage II, were evaluated with pelvic organ prolapse quantification (POPQ), MT, and CRM. Results. (a) 7.58% had (+) MT with CRM in USIg; (b) in up to 96.15% MT became negative during CRM in USIGP(A); (c) in 51.72% MT became positive only during CRM, as a sign for occult USI in USIGP(B); (d) point Aa (POPQ), which is bladder neck(BN) projection on the anterior vaginal wall, was situated higher in rest position (RP), but moved lower during the Valsalva maneuver (VM) in USIg versus USIGPg (P CRM could be useful arm in selection of (1) patients with isolated USI and great chance for postoperative failure; (2) patients with USI+GP stage I, who need GP repair during antistress surgery; (3) patients with USI + GP stage II, who need antistress procedure during vaginal hysterectomy.

  14. Addition of single-dose tenofovir and emtricitabine to intrapartum nevirapine to reduce perinatal HIV transmission.

    Science.gov (United States)

    Chi, Benjamin H; Chintu, Namwinga; Cantrell, Ronald A; Kankasa, Chipepo; Kruse, Gina; Mbewe, Felistas; Sinkala, Moses; Smith, Peter J; Stringer, Elizabeth M; Stringer, Jeffrey S A

    2008-06-01

    To determine the impact of adjuvant single-dose peripartum tenofovir/emtricitabine (TDF/FTC) on intrapartum/early postpartum HIV transmission. In the setting of routine short-course zidovudine (ZDV) and peripartum nevirapine (NVP) for perinatal HIV prevention, participants were randomized to single-dose TDF (300 mg)/FTC (200 mg) or to no intervention in labor. Six-week infant HIV infection was compared according to actual-use drug regimens. Of 397 women randomized, 355 (89%) had infants who were alive and active at 6 weeks postpartum. Of these, 18 (5.1%) were infected in utero and 6 (1.8%) were infected intrapartum/early postpartum. Among the 243 who used ZDV and NVP, intrapartum/early postpartum transmission was not reduced among infants whose mothers received TDF/FTC compared with those who did not (2 of 123 [1.6%] vs. 3 of 109 [2.8%]; P = 0.67). Among the 49 infants whose mothers did not receive antenatal ZDV but who had confirmed NVP ingestion, transmission similarly did not differ (0 of 19 [0%] vs. 1 of 26 [3.4%]). TDF/FTC was not significantly associated with reduced overall transmission (odds ratio [OR] = 0.7, 95% confidence interval [CI]: 0.3 to 1.6), even when other antiretroviral drugs were considered (adjusted OR = 0.8, 95% CI: 0.3 to 1.8). Adjuvant peripartum single-dose TDF/FTC did not reduce perinatal transmission. Whether a higher dose might be effective remains unknown but should be studied in settings in which NVP is used without antenatal ZDV.

  15. Hemodynamic parameters following bilateral internal iliac arteries ligation as a treatment of intrapartum hemorrhage.

    Science.gov (United States)

    Raba, Grzegorz; Baran, Piotr

    2009-03-01

    The internal iliac arteries ligation (IIAL) is a particularly effective method, maintaining fertility, of dealing with intrapartum hemorrhage. Hemodynamic evaluation of the ovarian arteries(OA) and uterine arteries (UA) in patients after IIAL. Study Group consisted of 6 women who underwent IIAL to treat intrapartum hemorrhage--without hysterectomy. Control Group consisted of 6 women, at the same age group, parity and time after delivery, who did not undergo IIAL. Perfusion characteristics were studied by means of a transvaginal Doppler system. Resistance index (RI), pulsatility index (PI) and systolic/diastolic ratio (S/D) were measured in the uterine and ovarian arteries. Nonparametric comparison of the two groups was performed with the help of Two-sample Wilcoxon rank-sum (Mann-Whitney) test. RESULTS 1. Change of perfusion in OA-PI: 1.40 vs. 3.76 Prob 0.05; S/D: 3.25 vs. 18.2 Prob Change of perfusion in UA-PI: 2.20 vs. 2.75 Prob > 0.05; RI 0.82 vs. 0.86 Prob > 0.05; SID: 5.28 vs. 7.81 Prob > 0.05. 1. IIAL as a way of treating intrapartum haemorrhage, causes the decrease of pulsatility index (PI) and systolic/diastolic ratio (S/D) in ovarian arteries. 2. Characteristic changes of PI, RI and S/D parameters in uterine arteries after IIAL have not been observed. 3. Changes of ovarian flow velocity parameters suggest the possibility of changes in the ovarian function.

  16. Colisional Cloud Debris and Propelled Evasive Maneuvers

    Science.gov (United States)

    Ferreira, L. S.; Jesus, A. D. C.; Carvalho, T. C. F.; Sousa, R. R.

    2017-10-01

    Space debris clouds exist at various altitudes in the environment outside the Earth. Fragmentation of debris and/or collision between the debris of a cloud increases the amount of debris, producing smaller debris. This event also increases significantly the chances of collision with operational vehicles in orbit. In this work we study clouds of debris that are close to a spacecraft in relation to its distance from the center of the Earth. The results show several layers of colliding debris depending on their size over time of evasive maneuvers of the vehicle. In addition, we have tested such maneuvers for propulsion systems with a linear and exponential mass variation model. The results show that the linear propulsion system is more efficient.

  17. Review of Tracktable for Satellite Maneuver Detection

    Energy Technology Data Exchange (ETDEWEB)

    Acquesta, Erin C.S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Valicka, Christopher G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hinga, Mark B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ehn, Carollan Beret [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-10-01

    As a tool developed to translate geospatial data into geometrical descriptors, Tracktable offers a highly efficient means to detect anomalous flight and maritime behavior. Following the success of using geometrical descriptors for detecting anomalous trajectory behavior, the question of whether Tracktable could be used to detect satellite maneuvers arose. In answering this question, this re- port will introduce a brief description of how Tracktable has been used in the past, along with an introduction to the fundamental properties of astrodynamics for satellite trajectories. This will then allow us to compare the two problem spaces, addressing how easily the methods used by Tracktable will translate to orbital mechanics. Based on these results, we will then be able to out- line the current limitations as well as possible path forward for using Tracktable to detect satellite maneuvers.

  18. Fate of remnant sinuses of Valsalva in patients with bicuspid and trileaflet valves undergoing aortic valve, ascending aorta, and aortic arch replacement.

    Science.gov (United States)

    Milewski, Rita Karianna; Habertheuer, Andreas; Bavaria, Joseph E; Siki, Mary; Szeto, Wilson Y; Krause, Eric; Korutla, Varun; Desai, Nimesh D; Vallabhajosyula, Prashanth

    2017-08-01

    In patients presenting with aortic valvulopathy with concomitant ascending aortic aneurysm, surgical management of the sinus of Valsalva segment remains undefined, especially for moderately dilated aortic roots. In patients with this pathology undergoing aortic valve replacement with supracoronary ascending aorta replacement, we assessed the fate of the remnant preserved sinus of Valsalva segment stratified by aortic valve morphology and pathology. From 2002 to 2015, 428 patients underwent elective aortic valve replacement with supracoronary ascending aorta replacement. Patients were stratified on the basis of valvular morphology (bicuspid aortic valve [n = 254] and tricuspid aortic valve [n = 174]), valvular pathology (bicuspid aortic valve with aortic stenosis [n = 178], bicuspid aortic valve with aortic insufficiency [n = 76], tricuspid aortic valve with aortic stenosis [n = 61], tricuspid aortic valve with aortic insufficiency [n = 113]), and preoperative sinus of Valsalva dimensions (45 mm). Kaplan-Meier analysis revealed no significant difference in freedom from reoperation in tricuspid aortic valve versus bicuspid aortic valve (P = .576). Multivariable Cox regression model performed with sinus of Valsalva dimensions at baseline and follow-up as time-varying covariates did not adversely affect survival. A repeated-measure, mixed-effects model constructed to assess longitudinal sinus of Valsalva trends revealed that the retained sinus of Valsalva dimensions remain stable over long-term follow-up (discharge to ≥10 years), irrespective of valvular morphology/pathology (bicuspid aortic valve with aortic insufficiency, tricuspid aortic valve with aortic insufficiency, tricuspid aortic valve with aortic stenosis) and preoperative sinus of Valsalva groups (45 mm). In patients with nonaneurysmal sinuses of Valsalva undergoing aortic valve replacement with supracoronary ascending aorta replacement, the sinus segment can be preserved irrespective of

  19. A rare case of unruptured aneurysm of left coronary sinus of Valsalva accompanied with patent foramen ovale and atrial fibrillation detected after cardiac etiology stroke

    Directory of Open Access Journals (Sweden)

    Wolfgang Hohenforst-Schmidt

    2017-01-01

    Full Text Available We present a rare case of a 74 year old female with unruptured aneurysm of the left coronary sinus of Valsalva accompanied with patent foramen ovale and atrial fibrillation. This rare combination was detected during diagnostics for a cardiac etiology stroke. The left coronary sinus of Valsalva was reconstructed using an autologous pericardial patch, the left atrial appendage closed, left atrial ablation performed with cooled radiofrequency and the patent foramen ovale sutured directly. The patient was dismissed on the 12th postoperative day after having an uncomplicated postoperative course.

  20. Intrapartum caesarean rates differ significantly between ethnic groups--relationship to induction.

    LENUS (Irish Health Repository)

    Ismail, Khadijah I

    2012-01-31

    OBJECTIVE: Given international variation in obstetric practices and outcomes, comparison of labour outcomes in different ethnic groups could provide important information regarding the underlying reasons for rising caesarean delivery rates. Increasing numbers of women from Eastern European countries are now delivering in Irish maternity hospitals. We compared labour outcomes between Irish and Eastern European (EE) women in a large tertiary referral center. STUDY DESIGN: This was a prospective consecutive cohort study encompassing a single calendar year. The cohort comprised 5550 Irish and 867 EE women delivered in a single institution in 2009. Women who had multiple pregnancies, breech presentation, and elective or pre-labour caesarean sections (CS) were excluded. Data obtained from birth registers included maternal age, nationality, parity, gestation, onset of labour, mode of delivery and birth weight. RESULTS: The overall intrapartum CS rate was 11.4% and was significantly higher in Irish compared to EE women (11.8% vs. 8.8%; p=0.008). The proportion of primiparas was lower in Irish compared to EE women (44.8% vs. 63.6%; p<0.0001). The intrapartum CS rate was almost doubled in Irish compared to EE primiparas (20.7% vs. 11.0%; p<0.0001). Analysis of primiparas according to labour onset revealed a higher intrapartum CS rate in Irish primiparas in both spontaneous (13.5% vs. 7.2%; p<0.0001) and induced labour (29.5% vs. 19.3%; p=0.005). Irish women were older with 19.7% of primiparas aged more than 35, compared to 1.6% of EE women (p<0.0001). The primigravid CS rate in Irish women was significantly higher in women aged 35 years or older compared women aged less than 35 (30.6% vs. 18.3%; p<0.0001) consistent in both spontaneous and induced labour. The primiparous induction rate was 45.4% in Irish women compared to 32% in EE women, and more Irish women were induced before 41 weeks gestation. CONCLUSION: The results highlight that primigravid intrapartum CS rates were

  1. Patterns in primary midwife-led care in the Netherlands. Trends and variation intrapartum referrals.

    OpenAIRE

    Offerhaus, P.M.

    2015-01-01

    Summary This thesis describes and analyses labours of healthy women in primary midwife-led care in the years 2000-2008. During the study period the intrapartum referral rate from primary midwife-led care to secondary obstetrician-led care increased. As primary care midwives have to hand over care in case of such a referral, this resulted in more discontinuity of care for women. Non-urgent referral reasons such as request for pain relief and a perceived lack of progress explained this rise. Th...

  2. Ex utero intrapartum treatment for an infant with cerebro-costo-mandibular syndrome.

    Science.gov (United States)

    Ogasawara, Kei; Honda, Yoshinobu; Hosoya, Mitsuaki

    2014-08-01

    Cerebro-costo-mandibular syndrome (CCMS) is a rare disorder characterized by multiple rib abnormalities, micrognathia described as Pierre-Robin sequence, and cerebral involvement. Appropriate management of respiratory distress immediately after birth is crucial to rescue these patients. A boy, having a mother with Pierre-Robin sequence and a sister with CCMS, was diagnosed prenatally with CCMS and successfully treated with ex utero intrapartum treatment (EXIT) at 36 weeks 6 days of gestation. EXIT would be an effective option for rescuing patients with prenatally diagnosed CCMS and preventing neonatal hypoxia. © 2014 Japan Pediatric Society.

  3. Geostationary Collocation: Case Studies for Optimal Maneuvers

    Science.gov (United States)

    2016-03-01

    travel from edge to edge, and finish with two days in the last case. It is worth noting that we could not fit the whole longitude libration in the...DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE GEOSTATIONARY COLLOCATION: CASE STUDIES FOR OPTIMAL MANEUVERS 5. FUNDING NUMBERS 6...distribution is unlimited 12b. DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) Satellite collocation is not a new topic in the space community

  4. Identifying tacit strategies in aircraft maneuvers

    Science.gov (United States)

    Lewis, Charles M.; Heidorn, P. B.

    1991-01-01

    Two machine-learning methods are presently used to characterize the avoidance strategies used by skilled pilots in simulated aircraft encounters, and a general framework for the characterization of the strategic components of skilled behavior via qualitative representation of situations and responses is presented. Descriptions of pilot maneuvers that were 'conceptually equivalent' were ascertained by a concept-learning algorithm in conjunction with a classifier system that employed a generic algorithm; satisficing and 'buggy' strategies were thereby revealed.

  5. Association between Intrapartum Magnesium Administration and the Incidence of Maternal Fever: A Retrospective Cross-sectional Study.

    Science.gov (United States)

    Lange, Elizabeth M S; Segal, Scott; Pancaro, Carlo; Wong, Cynthia A; Grobman, William A; Russell, Gregory B; Toledo, Paloma

    2017-12-01

    Intrapartum maternal fever is associated with several adverse neonatal outcomes. Intrapartum fever can be infectious or inflammatory in etiology. Increases in interleukin 6 and other inflammatory markers are associated with maternal fever. Magnesium has been shown to attenuate interleukin 6-mediated fever in animal models. We hypothesized that parturients exposed to intrapartum magnesium would have a lower incidence of fever than nonexposed parturients. In this study, electronic medical record data from all deliveries at Northwestern Memorial Hospital (Chicago, Illinois) between 2007 and 2014 were evaluated. The primary outcome was intrapartum fever (temperature at or higher than 38.0°C). Factors associated with the development of maternal fever were evaluated using a multivariable logistic regression model. Propensity score matching was used to reduce potential bias from nonrandom selection of magnesium administration. Of the 58,541 women who met inclusion criteria, 5,924 (10.1%) developed intrapartum fever. Febrile parturients were more likely to be nulliparous, have used neuraxial analgesia, and have been delivered via cesarean section. The incidence of fever was lower in women exposed to magnesium (6.0%) than those who were not (10.2%). In multivariable logistic regression, women exposed to magnesium were less likely to develop a fever (adjusted odds ratio = 0.42 [95% CI, 0.31 to 0.58]). After propensity matching (N = 959 per group), the odds ratio of developing fever was lower in women who received magnesium therapy (odds ratio = 0.68 [95% CI, 0.48 to 0.98]). Magnesium may play a protective role against the development of intrapartum fever. Future work should further explore the association between magnesium dosing and the incidence of maternal fever.

  6. Aerodynamic Flow Control of a Maneuvering Airfoil

    Science.gov (United States)

    Brzozowski, Daniel P.; Culp, John; Glezer, Ari

    2010-11-01

    The unsteady aerodynamic forces and moments on a maneuvering, free-moving airfoil are varied in wind tunnel experiments by controlling vorticity generation/accumulation near the surface using hybrid synthetic jet actuators. The dynamic characteristics of the airfoil that is mounted on a 2-DOF traverse are controlled using position and attitude feedback loops that are actuated by servo motors. Bi-directional changes in the pitching moment are induced using controllable trapped vorticity concentrations on the suction and pressure surfaces near the trailing edge. The dynamic coupling between the actuation and the time-dependent flow field is characterized using simultaneous force and velocity measurements that are taken phase-locked to the commanded actuation waveform. The time scales associated with the actuation process is determined from PIV measurements of vorticity flux downstream of the trailing edge. Circulation time history shows that the entire flow over the airfoil readjusts within about 1.5 TCONV, which is about two orders of magnitude shorter than the characteristic time associated with the controlled maneuver of the wind tunnel model. This illustrates that flow-control actuation can be typically effected on time scales commensurate with the flow's convective time scale, and that the maneuver response is only limited by the inertia of the platform. Supported by AFSOR.

  7. Cardioversion of a supraventricular tachycardia (SVT) in a 7-year-old using a postural modification of the Valsalva manoeuvre.

    Science.gov (United States)

    Morley-Smith, Edward John; Gagg, James; Appelboam, Andrew

    2017-05-04

    A boy aged 7 years presented with his parents to the emergency department (ED). He had a known diagnosis of paroxysmal supraventricular tachycardia (SVT) and was under the care of paediatricians. He had been suffering episodes of palpitations and chest pain for over a year and had been prescribed atenolol 25 mg ON, though the side effects meant he had not taken it for a month prior to presentation. He had 2 previous confirmed episodes of SVT, one that reverted with Valsalva manoeuvres, and the other with intravenous adenosine. In the ED, an ECG was recorded showing SVT at 180 bpm. Aside from his tachycardia, he was haemodynamically stable. The postural modification of the Valsalva technique was performed within 5 min of arrival, with reversion to sinus rhythm occurring during the leg-lift phase on the first attempt. After 30 min of observation, the child remained stable and was discharged home. 2017 BMJ Publishing Group Ltd.

  8. Intrapartum electrocardiogram alteration in fetuses with congenital heart disease: a case-control study.

    Science.gov (United States)

    Gay, Estelle; Bornallet, Géraldine; Gaucherand, Pascal; Doret, Muriel

    2015-11-01

    To assess if the fetal electrocardiogram especially ST segment is modified by congenital heart diseases: modifications in frequencies of the different ST events and modifications in signal quality. A retrospective case-control study, comparing frequencies of the different ST events and the quality of the signal between fetuses with congenital heart diseases and fetuses without congenital heart disease. From 2000 to 2011, fifty-eight fetuses with congenital heart disease had their heart rate recording using a STAN device during labor. Control group was fetuses who were born just before a case and had a STAN as a second line for intrapartum surveillance. Cases and controls were matched on parity, gestational age at birth, presence of growth restriction and umbilical artery pH. Frequencies of the different ST event and quality of the signal were first analyzed for the global labor recording, and then separately for the first and the second phase of labor. No statistically significant difference in ST event frequencies between fetuses with congenital heart disease and the control group was found. Regarding the quality of the signal, 11.49% (±18.82) of recording time is a signal loss for fetus with congenital heart disease whereas only 5.18% (±10.67) for the control group (p=0.028). This is the first study investigating for intrapartum electrocardiogram modification in fetus with congenital heart disease. Congenital heart diseases do not modify frequencies of ST events. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  9. Context matters: Successes and challenges of intrapartum care scale-up in four districts of Afghanistan.

    Science.gov (United States)

    Tappis, Hannah; Koblinsky, Marge; Winch, Peter J; Turkmani, Sabera; Bartlett, Linda

    2016-01-01

    Reducing preventable maternal mortality and achieving Sustainable Development Goal targets for 2030 will require increased investment in improving access to quality health services in fragile and conflict-affected states. This study explores the conditions that affect availability and utilisation of intrapartum care services in four districts of Afghanistan where mortality studies were conducted in 2002 and 2011. Information on changes in each district was collected through interviews with community members; service providers; and district, provincial and national officials. This information was then triangulated with programme and policy documentation to identify factors that affect the coverage of safe delivery and emergency obstetric care services. Comparison of barriers to maternal health service coverage across the four districts highlights the complexities of national health policy planning and resource allocation in Afghanistan, and provides examples of the types of challenges that must be addressed to extend the reach of life-saving maternal health interventions to women in fragile and conflict-affected states. Findings suggest that improvements in service coverage must be measured at a sub-national level, and context-specific service delivery models may be needed to effectively scale up intrapartum care services in extremely remote or insecure settings.

  10. The chance finding at multislice computed tomography coronary angiography of an ectopic origin of the left circumflex coronary artery from the right sinus of Valsalva.

    Science.gov (United States)

    Dattilo, Giuseppe; Lamari, Annalisa; Messina, Francesco; Imbalzano, Egidio; Salamone, Ignazio; Carerj, Scipione; Marte, Filippo; Patanè, Salvatore

    2011-06-02

    Anomalous coronary arteries occur in less than 2% of the general population. Most coronary anomalies are clinically asymptomatic. However some of them may present with chest pain, syncope, heart failure and sudden death. Acute myocardial infarction has been also described. Extravascular coronary compression results in dynamic obstruction which can cause effort angina as well as syncope and anomalous coronary arteries with an inter-arterial course are associated with sudden cardiac death. Anomalous origin of the circumflex coronary artery from the right sinus of Valsalva is thought to be of little clinical significance without the presence of severe narrowing of the vessel. Adequate visualization of the anomaly is essential for proper patient management. It has reported the full capability and accuracy of computed tomography coronary angiography in the identification and evaluation of the ectopic origin of the left circumflex coronary artery from the right sinus of Valsalva, displaying accurately the origin, size, course, and relationship of the anomalous vessel with respect to surrounding structures. We report a case of chance finding at multislice computed tomography coronary angiography of an ectopic origin of the left circumflex coronary artery from the right sinus of Valsalva. Also this case focuses attention on the anomalous origin of the circumflex coronary artery from the right sinus of Valsalva and confirms the full capability and accuracy of computed tomography coronary angiography in its adequate visualization. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

  11. [Surgical treatment for pseudoaneurysm of the sinus of valsalva ruptured into the right atrium after mycotic right coronary artery aneurysm repair;report of a case].

    Science.gov (United States)

    Hirai, Hidekazu; Sasaki, Yasuyuki; Hosono, Mitsuharu; Bito, Yasuyuki; Nakahira, Atsushi; Suehiro, Yasuo; Kaku, Daisuke; Miyabe, Makoto; Suehiro, Shigefumi

    2015-02-01

    A 67-year-old man was admitted to our hospital by ambulance after syncope due to complete A-V block. He had received surgical treatment for mycotic aneurysm of the right coronary artery 3 months before, with patch plasty of the right sinus of Valsalva and bypass grafting to the right coronary artery (RCA) as well as the left anterior descending branch. Computed tomography revealed pseudoaneurysm of the right Valsalva sinus of about 8 cm in diameter and a shunt flow to the right atrium. The previous bypass graft to RCA had been occluded due to compression by the aneurysm. As he was in a shock state, emergency operation was performed. Cardiopulmonary bypass was first established, and after the rectal temperature reached to 26 degrees centigrade, the chest was opened. The pseudoaneurysm burst out when the sternum was re-opened. Under circulatory arrest, the ascending aorta was clamped, and then the circulation was resumed. The previous bovine pericardium patch repairing the Valsalva sinus was detached due to infection, and mural thrombus and pus were observed in the aneurysm. At the bottom of the aneurysm, a fistula connected to the right atrium was found. Debridement around the aneurysm was performed as much as possible. The defect of the Valsalva sinus was repaired with a Dacron patch immersed in gentian violet. The postoperative course was uneventful without any recurrence of infection.

  12. Posterior arm shoulder dystocia alleviated by the Zavanelli maneuver.

    Science.gov (United States)

    Gherman, Robert B; Ouzounian, Joseph G; Chauhan, Suneet

    2010-10-01

    The exact role of the Zavanelli maneuver for the management of shoulder dystocia still remains to be defined. None of the previously reported cases in which the Zavanelli maneuver has been employed described impaction of posterior fetal arm. At 40 weeks' gestation, a nulliparous patient with gestational diabetes, who underwent vacuum delivery, delivered an infant with shoulder dystocia. McRoberts' maneuver, suprapubic pressure, midline episiotomy, and Woods' maneuver were all unsuccessful in alleviating the shoulder dystocia. The posterior fetal arm was noted to be persistently impacted, so the Zavanelli maneuver was used to deliver an unsuspected macrosomic (4215 g) infant. The newborn, at the age of 3 years, has a right Erb's palsy. The Zavanelli maneuver can be used to alleviate a posterior arm shoulder dystocia, though there may be concomitant neurological injury. © Thieme Medical Publishers.

  13. Aqua/Aura Updated Inclination Adjust Maneuver Performance Prediction Model

    Science.gov (United States)

    Boone, Spencer

    2017-01-01

    This presentation will discuss the updated Inclination Adjust Maneuver (IAM) performance prediction model that was developed for Aqua and Aura following the 2017 IAM series. This updated model uses statistical regression methods to identify potential long-term trends in maneuver parameters, yielding improved predictions when re-planning past maneuvers. The presentation has been reviewed and approved by Eric Moyer, ESMO Deputy Project Manager.

  14. Adaptive Target Tracking for Underwater Maneuvering Targets.

    Science.gov (United States)

    1979-12-01

    concenetrate on the bearings-only approach. In this method the Observer monitors his bearing to the Source, over a period of time. Usually the Observer must...developed in [ 5] was earlier applied with much success to tracking maneuvering air targets. This approach will now be applied in the underwater environment...April 1977. [11] A. H. Jazwinski, Stochastic Processes and Filtering Theory, Academic Press, New York, 1970. [12] D. H. Halliday, and R. Resnick, Physics, John Wiley & Sons, Inc., New York, 1966. hI

  15. Artificial immune system approach for air combat maneuvering

    Science.gov (United States)

    Kaneshige, John; Krishnakumar, Kalmanje

    2007-04-01

    Since future air combat missions will involve both manned and unmanned aircraft, the primary motivation for this research is to enable unmanned aircraft with intelligent maneuvering capabilities. During air combat maneuvering, pilots use their knowledge and experience of maneuvering strategies and tactics to determine the best course of action. As a result, we try to capture these aspects using an artificial immune system approach. The biological immune system protects the body against intruders by recognizing and destroying harmful cells or molecules. It can be thought of as a robust adaptive system that is capable of dealing with an enormous variety of disturbances and uncertainties. However, another critical aspect of the immune system is that it can remember how previous encounters were successfully defeated. As a result, it can respond faster to similar encounters in the future. This paper describes how an artificial immune system is used to select and construct air combat maneuvers. These maneuvers are composed of autopilot mode and target commands, which represent the low-level building blocks of the parameterized system. The resulting command sequences are sent to a tactical autopilot system, which has been enhanced with additional modes and an aggressiveness factor for enabling high performance maneuvers. Just as vaccinations train the biological immune system how to combat intruders, training sets are used to teach the maneuvering system how to respond to different enemy aircraft situations. Simulation results are presented, which demonstrate the potential of using immunized maneuver selection for the purposes of air combat maneuvering.

  16. Patterns and Determinants of Care-Seeking for Antepartum and Intrapartum Complications in Rural Bangladesh: Results from a Cohort Study.

    Directory of Open Access Journals (Sweden)

    Rasheda Khanam

    Full Text Available The burden of maternal complications during antepartum and intrapartum periods is high and care seeking from a trained provider is low, particularly in low middle income countries of sub-Saharan Africa and South Asia. Identification of barriers to access to trained care and development of strategies to address them will contribute to improvements in maternal health. Using data from a community-based cohort of pregnant women, this study identified the prevalence of antepartum and intrapartum complications and determinants of care-seeking for these complications in rural Bangladesh.The study was conducted in 24,274 pregnant women between June 2011 and December 2013 in rural Sylhet district of Bangladesh. Women were interviewed during pregnancy to collect data on demographic and socioeconomic characteristics; prior miscarriages, stillbirths, live births, and neonatal deaths; as well as data on their ability to make decision to go to health center alone. They were interviewed within the first 7 days of child birth to collect data on self-reported antepartum and intrapartum complications and care seeking for those complications. Bivariate analysis was conducted to explore association between predisposing (socio-demographic, enabling (economic, perceived need, and service related factors with care-seeking for self-reported antepartum and intrapartum complications. Multivariable multinomial logistic regression was performed to examine the association of selected factors with care-seeking for self-reported antepartum and intrapartum complications adjusting for co-variates.Self-reported antepartum and intrapartum complications among women were 14.8% and 20.9% respectively. Among women with any antepartum complication, 58.9% sought care and of these 46.5% received care from a trained provider. Of the women with intrapartum complications, 61.4% sought care and of them 46.5% did so from a trained provider. Care-seeking for both antepartum and intrapartum

  17. General and Specific Strategies Used to Facilitate Locomotor Maneuvers.

    Directory of Open Access Journals (Sweden)

    Mengnan Wu

    Full Text Available People make anticipatory changes in gait patterns prior to initiating a rapid change of direction. How they prepare will change based on their knowledge of the maneuver. To investigate specific and general strategies used to facilitate locomotor maneuvers, we manipulated subjects' ability to anticipate the direction of an upcoming lateral "lane-change" maneuver. To examine specific anticipatory adjustments, we observed the four steps immediately preceding a maneuver that subjects were instructed to perform at a known time in a known direction. We hypothesized that to facilitate a specific change of direction, subjects would proactively decrease margin of stability in the future direction of travel. Our results support this hypothesis: subjects significantly decreased lateral margin of stability by 69% on the side ipsilateral to the maneuver during only the step immediately preceding the maneuver. This gait adaptation may have improved energetic efficiency and simplified the control of the maneuver. To examine general anticipatory adjustments, we observed the two steps immediately preceding the instant when subjects received information about the direction of the maneuver. When the maneuver direction was unknown, we hypothesized that subjects would make general anticipatory adjustments that would improve their ability to actively initiate a maneuver in multiple directions. This second hypothesis was partially supported as subjects increased step width and stance phase hip flexion during these anticipatory steps. These modifications may have improved subjects' ability to generate forces in multiple directions and maintain equilibrium during the onset and execution of the rapid maneuver. However, adapting these general anticipatory strategies likely incurred an additional energetic cost.

  18. The simulation of an ex utero intrapartum procedure to extracorporeal membrane oxygenation.

    Science.gov (United States)

    Auguste, Tamika C; Boswick, J Aidan; Loyd, Mary K; Battista, Alexis

    2011-02-01

    We report a case of using simulation to aid in the performance of ex utero intrapartum treatment (EXIT) procedure to extracorporeal membrane oxygenation (ECMO). A primigravid with a fetus who was diagnosed with hypoplastic left heart syndrome was scheduled for an EXIT to ECMO procedure to be done by members of her obstetrical and neonatal teams. It would be the first time any of the members of the 2 teams would work together. Simulation was used to allow all involved parties to experience the procedure before the live operation. In addition, the simulation enabled the interdisciplinary teams to work with each other, identify possible complications, and further plan the coordination during the event. The EXIT to ECMO surgery was completed successfully. The use of low-fidelity, cost-effective simulation during a surgical rehearsal can give a surgical team critical advantage when performing a rare and/or complex procedure. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. The shifting sands of medico-legal intra-partum Ctg (I-P Ctg) monitoring.

    Science.gov (United States)

    Buttigieg, George G

    2016-03-01

    Intra-partum (IP) surveillance of the unborn child by cardiotacography (CTG) monitoring is the commonest obstetric procedure in the developed world.(1) It is also the most medico-legally contested obstetric procedure in labour. In 2011, 'birth asphyxia' comprised 50% of the UK National Health Service (NHS) litigation costs,(2) and in the 2000-2010 decade, the same NHS paid out £3.1 billion for maternity medico-legal claims (the highest of any speciality), mostly involving cerebral palsy and CTG misinterpretation.(3) This article looks at a number of characteristics of IP CTG monitoring which argue for its questionable solidity of base in court proceedings. © The Author(s) 2015.

  20. Monitoring of antepartum and intrapartum fetal hypoxemia: pathophysiological basis and available techniques.

    Science.gov (United States)

    Clerici, G; Luzietti, R; Di Renzo, G C

    2001-01-01

    The challenge of obstetric surveillance is to identify those fetuses whose physiological defence mechanisms are compromised, in order to be able to act before decompensation has occurred. During the antenatal period, the evaluation of fetal hemodynamic adaptation to hypoxemia and the assessment of its chronological evolution by Doppler technology are crucial. During the intrapartum period, the relative inaccessibility of the fetus and the complexity of the pathophysiology of fetal oxygenation make it difficult to obtain and interpret information on the fetal response to labor stress. Due to the limitations of cardiotocography, additional information is required for appropriate decision making during labor. Current evidence suggests that modern technology applied to fetal surveillance can provide useful additional information that can improve our capacity to interpret fetal reactions to labor events. Copyright 2001 S. Karger AG, Basel

  1. The effect of prenatal and intrapartum care on the stillbirth rate among women in rural Ethiopia.

    Science.gov (United States)

    Ballard, Karen; Belete, Zelalem; Kinfu, Hirut; Tadesse, Mebkyou; Amin, Mohammed; Atnafu, Habtamu

    2016-05-01

    To determine whether community-based prenatal and intrapartum care in Ethiopia results in a lower stillbirth rate. Between May and December 2014, a randomly selected sample of women in northern and eastern Ethiopia who had delivered a neonate in the preceding 12months completed a face-to-face survey about their experiences of maternal services and the fetal outcome for each delivery. The stillbirth rates among women delivering at home and at health facilities were compared. Overall, 4442 women completed surveys. Stillbirth was reported by 42 (1.7%) of the 2437 women who had received prenatal care and 53 (2.8%) of the 1921 women who did not receive prenatal care (P=0.01). The stillbirth rate was similar among women who delivered in a health center (27/1417 [1.9%]), in a hospital (6/126 [4.8%]), and at home (62/2725 [2.3%]; P=0.13). However, women experiencing an intrapartum emergency were twice as likely to deliver in a health facility (odds ratio 2.6, 95% confidence interval 2.2-3.0). Satisfaction with health-center care was moderately good (median score 77.5/100). The stillbirth rate was reduced among women receiving prenatal care, although delivering in a health facility did not reduce the risk of stillbirth. Improving the quality of health-center care could lead to their planned use for childbirth, which might reduce stillbirth rates. Copyright © 2016 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  2. A model to predict vaginal delivery in nulliparous women based on maternal characteristics and intrapartum ultrasound.

    Science.gov (United States)

    Eggebø, Tørbjorn Moe; Wilhelm-Benartzi, Charlotte; Hassan, Wassim A; Usman, Sana; Salvesen, Kjell A; Lees, Christoph C

    2015-09-01

    Accurate prediction of whether a nulliparous woman will have a vaginal delivery would be a major advance in obstetrics. The objective of the study was to develop such a model based on maternal characteristics and the results of intrapartum ultrasound. One hundred twenty-two nulliparous women in the first stage of labor were included in a prospective observational 2-centre study. Labor was classified as prolonged according to the respective countries' national guidelines. Fetal head position was assessed with transabdominal ultrasound and cervical dilatation by digital examination, and transperineal ultrasound was used to determine head-perineum distance and the presence of caput succedaneum. The subjects were divided into a testing set (n = 61) and a validation set (n = 61) and a risk score derived using multivariable logistic regression with vaginal birth as the outcome, which was dichotomized into no/cesarean delivery and yes/vaginal birth. Covariates included head-perineum distance, caput succedaneum, and occiput posterior position, which were dichotomized respectively into the following: ≤40 mm, >40 mm, <10 mm, ≥10 mm, and no, yes. Maternal age, gestational age, and maternal body mass index were included as continuous covariates. Dichotomized score is significantly associated with vaginal delivery (P = .03). Women with a score above the median had greater than 10 times the odds of having a vaginal delivery as compared with those with a score below the median. The receiver-operating characteristic curve showed an area under the curve of 0.853 (95% confidence interval, 0.678-1.000). A risk score based on maternal characteristics and intrapartum findings can predict vaginal delivery in nulliparous women in the first stage of labor. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. A Qualitative Study on Women's Experiences of Intrapartum Nursing Care at Tamale Teaching Hospital (TTH), Ghana.

    Science.gov (United States)

    Afaya, Agani; Yakong, Vida N; Afaya, Richard A; Salia, Solomon M; Adatara, Peter; Kuug, Anthony K; Nyande, Flex K

    2017-12-01

    Introduction: Labor and delivery process is an exciting, anxiety-provoking, but rewarding time for a woman and her family after successful delivery of a newborn. The intrapartum period is the time where mothers expect more care. Taking care of a mother through delivery with no side effects is the task of a professional midwife who is trained with the skill to take the responsibility of caring for mothers and babies. Therefore, the aim of this study was to explore mother's experiences regarding quality of intrapartum nursing/midwifery care. Methods: Focused ethnographic study was employed. Data were collected from May to June 2016 TTH, Ghana using semi structured interview guide. Purposive sampling was employed to recruit 20 participants. Eight individual interviews were conducted in the post natal ward after 48 hours of delivery, followed by three focus group discussions two weeks after delivery when mothers visited post natal clinic. Interviews lasted for about 30-45 minutes during each session. Data were analyzed using thematic analysis. Results: The average age of women were 29 years with ranging from 19-43 years. Participants' experiences of nursing/midwifery care during birth were influenced by reception and respect, provision of information, technical skill, providers' behavior, pain management and availability of nurses/midwives. Conclusion: The study findings have revealed that women's experience of care is affected by a wide range of determinants. Therefore, maternal health programs and policies in Ghana must take into account women's perspective on the care they need and their feedback on services they receive. Nursing education should re-enforce communication/relational skills.

  4. Early Gut Microbiota Perturbations Following Intrapartum Antibiotic Prophylaxis to Prevent Group B Streptococcal Disease.

    Directory of Open Access Journals (Sweden)

    Giuseppe Mazzola

    Full Text Available The faecal microbiota composition of infants born to mothers receiving intrapartum antibiotic prophylaxis with ampicillin against group B Streptococcus was compared with that of control infants, at day 7 and 30 of life. Recruited newborns were both exclusive breastfed and mixed fed, in order to also study the effect of dietary factors on the microbiota composition. Massive parallel sequencing of the V3-V4 region of the 16S rRNA gene and qPCR analysis were performed. Antibiotic prophylaxis caused the most marked changes on the microbiota in breastfed infants, mainly resulting in a higher relative abundance of Enterobacteriaceae, compared with control infants (52% vs. 14%, p = 0.044 and mixed-fed infants (52% vs. 16%, p = 0.13 NS at day 7 and in a lower bacterial diversity compared to mixed-fed infants and controls. Bifidobacteria were also particularly vulnerable and abundances were reduced in breastfed (p = 0.001 and mixed-fed antibiotic treated groups compared to non-treated groups. Reductions in bifidobacteria in antibiotic treated infants were also confirmed by qPCR. By day 30, the bifidobacterial population recovered and abundances significantly increased in both breastfed (p = 0.025 and mixed-fed (p = 0.013 antibiotic treated groups, whereas Enterobacteriaceae abundances remained highest in the breastfed antibiotic treated group (44%, compared with control infants (16% and mixed-fed antibiotic treated group (28%. This study has therefore demonstrated the short term consequences of maternal intrapartum antibiotic prophylaxis on the infant faecal microbial population, particularly in that of breastfed infants.

  5. Quality along the continuum: a health facility assessment of intrapartum and postnatal care in Ghana.

    Science.gov (United States)

    Nesbitt, Robin C; Lohela, Terhi J; Manu, Alexander; Vesel, Linda; Okyere, Eunice; Edmond, Karen; Owusu-Agyei, Seth; Kirkwood, Betty R; Gabrysch, Sabine

    2013-01-01

    To evaluate quality of routine and emergency intrapartum and postnatal care using a health facility assessment, and to estimate "effective coverage" of skilled attendance in Brong Ahafo, Ghana. We conducted an assessment of all 86 health facilities in seven districts in Brong Ahafo. Using performance of key signal functions and the availability of relevant drugs, equipment and trained health professionals, we created composite quality categories in four dimensions: routine delivery care, emergency obstetric care (EmOC), emergency newborn care (EmNC) and non-medical quality. Linking the health facility assessment to surveillance data we estimated "effective coverage" of skilled attendance as the proportion of births in facilities of high quality. Delivery care was offered in 64/86 facilities; only 3-13% fulfilled our requirements for the highest quality category in any dimension. Quality was lowest in the emergency care dimensions, with 63% and 58% of facilities categorized as "low" or "substandard" for EmOC and EmNC, respectively. This implies performing less than four EmOC or three EmNC signal functions, and/or employing less than two skilled health professionals, and/or that no health professionals were present during our visit. Routine delivery care was "low" or "substandard" in 39% of facilities, meaning 25/64 facilities performed less than six routine signal functions and/or had less than two skilled health professionals and/or less than one midwife. While 68% of births were in health facilities, only 18% were in facilities with "high" or "highest" quality in all dimensions. Our comprehensive facility assessment showed that quality of routine and emergency intrapartum and postnatal care was generally low in the study region. While coverage with facility delivery was 68%, we estimated "effective coverage" of skilled attendance at 18%, thus revealing a large "quality gap." Effective coverage could be a meaningful indicator of progress towards reducing maternal

  6. Quality along the continuum: a health facility assessment of intrapartum and postnatal care in Ghana.

    Directory of Open Access Journals (Sweden)

    Robin C Nesbitt

    Full Text Available To evaluate quality of routine and emergency intrapartum and postnatal care using a health facility assessment, and to estimate "effective coverage" of skilled attendance in Brong Ahafo, Ghana.We conducted an assessment of all 86 health facilities in seven districts in Brong Ahafo. Using performance of key signal functions and the availability of relevant drugs, equipment and trained health professionals, we created composite quality categories in four dimensions: routine delivery care, emergency obstetric care (EmOC, emergency newborn care (EmNC and non-medical quality. Linking the health facility assessment to surveillance data we estimated "effective coverage" of skilled attendance as the proportion of births in facilities of high quality.Delivery care was offered in 64/86 facilities; only 3-13% fulfilled our requirements for the highest quality category in any dimension. Quality was lowest in the emergency care dimensions, with 63% and 58% of facilities categorized as "low" or "substandard" for EmOC and EmNC, respectively. This implies performing less than four EmOC or three EmNC signal functions, and/or employing less than two skilled health professionals, and/or that no health professionals were present during our visit. Routine delivery care was "low" or "substandard" in 39% of facilities, meaning 25/64 facilities performed less than six routine signal functions and/or had less than two skilled health professionals and/or less than one midwife. While 68% of births were in health facilities, only 18% were in facilities with "high" or "highest" quality in all dimensions.Our comprehensive facility assessment showed that quality of routine and emergency intrapartum and postnatal care was generally low in the study region. While coverage with facility delivery was 68%, we estimated "effective coverage" of skilled attendance at 18%, thus revealing a large "quality gap." Effective coverage could be a meaningful indicator of progress towards

  7. Intrapartum and neonatal outcomes in singleton pregnancies following conception by assisted reproduction techniques.

    Science.gov (United States)

    Rozdarz, Kellie M; Flatley, Christopher J; Kumar, Sailesh

    2017-12-01

    To characterise maternal demographics and ascertain whether clinically important differences exist in the intrapartum and neonatal outcomes associated with assisted reproductive technology (ART). A retrospective study was undertaken between January 2007 and December 2013 of all singleton pregnancies conceived via ART at a major tertiary unit in Brisbane, Australia. Intrapartum outcomes were mode of delivery and indication for emergency caesarean. Neonatal outcomes investigated were gestation at delivery, birth weight, Apgar scores, acidosis at birth, respiratory distress, need for resuscitation, admission to neonatal intensive care and stillbirth. There were 4733 (7.4%) ART and 59 277 (92.6%) spontaneous conception pregnancies. Women who conceived using ART were less likely to have a spontaneous vaginal delivery (odds ratio (OR) 0.60, 95% CI 0.57-0.64) and were more likely to require operative or assisted birth: elective caesarean (adjusted OR (aOR) 1.31, 95% CI 1.22-1.40), emergency caesarean (aOR 1.19, 95% CI 1.09-1.28), or instrumental delivery (aOR 1.45, 95% CI 1.32-1.58). Neonates who were conceived using ART were less likely to be born at term (aOR 0.64, 95% CI 0.58-0.71) and have lower birth weights. No differences were observed in rates of respiratory distress, admission to the neonatal intensive care unit, or stillbirth between the ART and spontaneous conception cohorts. The odds of neonatal acidosis (OR 0.71, 95% CI0.63-0.81) were lower in the ART cohort. Although higher rates of operative deliveries were seen for women who conceive using ART, neonatal outcomes were generally no different between the two cohorts. © 2017 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  8. Intrapartum care and substandard care: juridical recommendations to reduce the risk of liability.

    Science.gov (United States)

    Eggermont, Marlies

    2015-07-01

    To develop juridical recommendations to reduce medical liability of the obstetrician, providing intrapartum care. 107 legal proceedings of the past 40 years from Belgium, France and the Netherlands, involving medical negligence of the obstetrician during intrapartum care, were analyzed in depth. The legal databases used were Jura and Judit (Belgium), Legifrance, Juricaf and Dalloz (France) and Recht, Rechtspraak (the Netherlands). A minority of the cases were retrieved through contacts with insurance companies (Belgium only) and courts. The judicial assessment of negligence is focused on four domains of expertise of the obstetrician: 36 % (38/107) recognizing a specific pathology, 33 % (35/107) interpreting fetal monitoring, 19 % (21/107) performing a forceps/vacuum-assisted delivery and 12 % (13/107) managing shoulder dystocia. The highest liability rate of 86 % (30/35) was reflected in the category of interpreting fetal monitoring. To reduce the liability rate of 66 %, several policy recommendations can be made. Respond to the first symptoms of obstetric complications (particularly placental abruption and uterine rupture). Secondly, respond to disturbing messages of the midwife concerning fetal distress and evaluate every deviation in fetal heart rate monitoring. Education concerning the interpretation of fetal monitoring is a must for every midwife and obstetrician. Use proper methods to monitor the heart rate to optimize the quality of the signal. The third recommendation is to be cautious about opting for a forceps/vacuum-assisted delivery, consider all circumstances. Consider the risk of failed instrumental delivery. And finally in relation to shoulder dystocia, recognize the risk factors by ordering further examinations to purchase a diagnosis.

  9. Linking spatial and dynamic models for traffic maneuvers

    DEFF Research Database (Denmark)

    Olderog, Ernst-Rüdiger; Ravn, Anders Peter; Wisniewski, Rafal

    2015-01-01

    For traffic maneuvers of multiple vehicles on highways we build an abstract spatial and a concrete dynamic model. In the spatial model we show the safety (collision freedom) of lane-change maneuvers. By linking the spatial and dynamic model via suitable refinements of the spatial atoms to distance...

  10. Braking news: link between crash severity and crash avoidance maneuvers

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    This study focused on the link between crash severity and crash avoidance maneuvers. Various emergency lateral and speed control maneuvers were considered in response to different critical events that made the crash imminent. Partial proportional odds models that allowed for changes in effects ac...

  11. Safety analysis of passing maneuvers using extreme value theory

    Directory of Open Access Journals (Sweden)

    Haneen Farah

    2017-04-01

    The results indicate that this is a promising approach for safety evaluation. On-going work of the authors will attempt to generalize this method to other safety measures related to passing maneuvers, test it for the detailed analysis of the effect of demographic factors on passing maneuvers' crash probability and for its usefulness in a traffic simulation environment.

  12. 14 CFR 25.331 - Symmetric maneuvering conditions.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Symmetric maneuvering conditions. 25.331 Section 25.331 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... determining elevator angles and chordwise load distribution in the maneuvering conditions of paragraphs (b...

  13. Actuator Characterization of Man Portable Precision Maneuver Concepts

    Science.gov (United States)

    2014-03-01

    limited due to gun recoil limits on the human shoulder. Lastly, rifled guns often induce high spin rates (hundreds or thousands of cycles per second...small diameter, high spin rate, gun -launched projectiles is proposed. The performance of the actuation technology associated with this class of maneuver...5 Table 2. Individual experiment maneuver system parameters

  14. 14 CFR 23.155 - Elevator control force in maneuvers.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Elevator control force in maneuvers. 23.155 Section 23.155 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Controllability and Maneuverability § 23.155 Elevator control force in maneuvers. (a) The elevator control force...

  15. Planar reorientation maneuvers of space multibody systems using internal controls

    Science.gov (United States)

    Reyhanoglu, Mahmut; Mcclamroch, N. H.

    1992-01-01

    In this paper a reorientation maneuvering strategy for an interconnection of planar rigid bodies in space is developed. It is assumed that there are no exogeneous torques, and torques generated by joint motors are used as means of control so that the total angular momentum of the multibody system is a constant, assumed to be zero in this paper. The maneuver strategy uses the nonintegrability of the expression for the angular momentum. We demonstrate that large-angle maneuvers can be designed to achieve an arbitrary reorientation of the multibody system with respect to an inertial frame. The theoretical background for carrying out the required maneuvers is briefly summarized. Specifications and computer simulations of a specific reorientation maneuver, and the corresponding control strategies, are described.

  16. AIRCRAFT CONFLICTS RESOLUTION BY COURSE MANEUVERING

    Directory of Open Access Journals (Sweden)

    В. Харченко

    2011-02-01

    Full Text Available Enhancement of requirements for air traffic efficiency at increasing of flights intensity determines the necessity of development of new optimization methods for aircraft conflict resolutions. The statement of problem of optimal conflict resolutions at Cooperative Air Traffic Management was done. The method for optimal aircraft conflict  resolution by course maneuvering has been  developed. The method using dynamic programming provides planning of aircraft conflict-free trajectory with minimum length. The decomposition of conflict resolution process on phases and stages, definition of states, controls and recursive  equations for generation of optimal course control program were done. Computer modeling of aircraft conflict resolution by developed method was done

  17. Intrapartum and neonatal mortality in primary midwife-led and secondary obstetrician-led care in the Amsterdam region of the Netherlands: A retrospective cohort study

    NARCIS (Netherlands)

    Wiegerinck, M.M.J.; van der Goes, B.Y.; Ravelli, A.C.J.; van der Post, J.A.M.; Klinkert, J.; Brandenbarg, J.; Buist, F.C.D.; Wouters, M.G.A.J.; Tamminga, P.; de Jonge, A.; Mol, B.W.

    2015-01-01

    Objective: to compare intrapartum- and neonatal mortality and intervention rates in term women starting labour in primary midwife-led versus secondary obstetrician-led care. Design: retrospective cohort study. Setting: Amsterdam region of the Netherlands. Participants: women with singleton

  18. The characteristics of women who use hypnotherapy for intrapartum pain management: Preliminary insights from a nationally-representative sample of Australian women.

    Science.gov (United States)

    Steel, A; Frawley, J; Sibbritt, D; Broom, A; Adams, J

    2016-04-01

    This manuscript presents a preliminary examination of the characteristics of women who choose intrapartum hypnosis for pain management. Cross-sectional analysis of 2445 women (31-36 years) from a sub-study of the Australian Longitudinal Study on Women's Health (ALSWH), employing Fisher exact tests. Australia. Use of intrapartum hypnosis, or hypnobirthing, for pain management during labour and birth. Women using hypnobirthing were more likely to have consulted with an acupuncturist or naturopath, or attended yoga/meditation classes during pregnancy (phypnotherapy for intrapartum pain management less commonly identified as feeling safer knowing that an obstetrician is providing their care (phypnotherapy for intrapartum pain management. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Intrapartum-related neonatal encephalopathy incidence and impairment at regional and global levels for 2010 with trends from 1990

    Science.gov (United States)

    Lee, Anne CC; Kozuki, Naoko; Blencowe, Hannah; Vos, Theo; Bahalim, Adil; Darmstadt, Gary L.; Niermeyer, Susan; Ellis, Matthew; Robertson, Nicola J.; Cousens, Simon; Lawn, Joy E.

    2013-01-01

    Background: Intrapartum hypoxic events (“birth asphyxia”) may result in stillbirth, neonatal or postneonatal mortality, and impairment. Systematic morbidity estimates for the burden of impairment outcomes are currently limited. Neonatal encephalopathy (NE) following an intrapartum hypoxic event is a strong predictor of long-term impairment. Methods: Linear regression modeling was conducted on data identified through systematic reviews to estimate NE incidence and time trends for 184 countries. Meta-analyses were undertaken to estimate the risk of NE by sex of the newborn, neonatal case fatality rate, and impairment risk. A compartmental model estimated postneonatal survivors of NE, depending on access to care, and then the proportion of survivors with impairment. Separate modeling for the Global Burden of Disease 2010 (GBD2010) study estimated disability adjusted life years (DALYs), years of life with disability (YLDs), and years of life lost (YLLs) attributed to intrapartum-related events. Results: In 2010, 1.15 million babies (uncertainty range: 0.89–1.60 million; 8.5 cases per 1,000 live births) were estimated to have developed NE associated with intrapartum events, with 96% born in low- and middle-income countries, as compared with 1.60 million in 1990 (11.7 cases per 1,000 live births). An estimated 287,000 (181,000–440,000) neonates with NE died in 2010; 233,000 (163,000–342,000) survived with moderate or severe neurodevelopmental impairment; and 181,000 (82,000–319,000) had mild impairment. In GBD2010, intrapartum-related conditions comprised 50.2 million DALYs (2.4% of total) and 6.1 million YLDs. Conclusion: Intrapartum-related conditions are a large global burden, mostly due to high mortality in low-income countries. Universal coverage of obstetric care and neonatal resuscitation would prevent most of these deaths and disabilities. Rates of impairment are highest in middle-income countries where neonatal intensive care was more recently

  20. X-31 in flight - Mongoose Maneuver

    Science.gov (United States)

    1995-01-01

    Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at the Rockwell International facility, Palmdale, California, and the NASA Dryden Flight Research Center, Edwards, California, to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on October 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is an aircraft with a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack -- with the nose pitched up while the aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, pilot or both. Three thrust-vectoring paddles made of graphite epoxy mounted on the exhaust nozzle of the X-31 aircraft directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31 aircraft were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls

  1. An Estimation Algorithm for Detecting and Reconstructing Optimal Maneuvers from Measurement Residuals

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposed research addresses the problem of optimal maneuver detection and reconstruction with regards to an astrodynamics application. Maneuver detection and...

  2. Ship maneuvering digital simulator; Simulador digital de manobras de navios

    Energy Technology Data Exchange (ETDEWEB)

    Souza Junior, Jesse Rebello; Tannuri, Eduardo Aoun; Oshiro, Anderson Takehiro [Universidade de Sao Paulo (USP), SP (Brazil). Escola Politecnica. Dept. de Engenharia Naval e Oceanica

    2008-07-01

    This paper reports on two case studies making use of a digital simulator to investigate the maneuvering motions of ships in canals with shallow and restricted waters. The first case study corresponds to a maneuvering analysis conducted for the Port of Rio Grande (RS - Brazil), whose aim was to assess the potential impact upon maneuvers of the presence of a large offshore platform (the PETROBRAS P-53) which is to remain docked for several months at the Port to complete its construction. The second study made use of the simulator to evaluate the maneuvering conditions along the approach route and maneuvering basin of the Port of Ponta do Felix (PR - Brazil). The simulator includes a complete mathematical model of the ship dynamics in the horizontal plane when subjected to wind and current forces. It also comprises detailed models for the action of thrusters and propellers, both fixed and azimuth, employed to control maneuvers and dynamically position ships, as well as rudders and tugboats. He models used by the simulator allow for the effects of shallow and restricted waters, including the increase in resistance and lateral forces, increase in additional mass and the appearance of lateral and vertical suction (squatting). The simulator is implemented via an interactive interface through which the user is able to apply control actions (rudder angle, main engine, thrusters and tugboats) in real time during maneuvers, thereby reproducing to some extent the action of a pilot. (author)

  3. Constellation Mission Operation Working Group: ESMO Maneuver Planning Process Review

    Science.gov (United States)

    Moyer, Eric

    2015-01-01

    The Earth Science Mission Operation (ESMO) Project created an Independent Review Board to review our Conjunction Risk evaluation process and Maneuver Planning Process to identify improvements that safely manages mission conjunction risks, maintains ground track science requirements, and minimizes overall hours expended on High Interest Events (HIE). The Review Board is evaluating the current maneuver process which requires support by multiple groups. In the past year, there have been several changes to the processes although many prior and new concerns exist. This presentation will discuss maneuver process reviews and Board comments, ESMO assessment and path foward, ESMO future plans, recent changes and concerns.

  4. Diversity and composition of vaginal microbiota of pregnant women at risk for transmitting Group B Streptococcus treated with intrapartum penicillin.

    Science.gov (United States)

    Roesch, Luiz Fernando Wurdig; Silveira, Rita C; Corso, Andréa L; Dobbler, Priscila Thiago; Mai, Volker; Rojas, Bruna S; Laureano, Álvaro M; Procianoy, Renato S

    2017-01-01

    Administering intravenous antibiotics during labor to women at risk for transmitting Group B Streptococcus (GBS) can prevent infections in newborns. However, the impact of intrapartum antibiotic prophylaxis on mothers' microbial community composition is largely unknown. We compared vaginal microbial composition in pregnant women experiencing preterm birth at ≤ 32 weeks gestation that received intrapartum antibiotic prophylaxis with that in controls. Microbiota in vaginal swabs collected shortly before delivery from GBS positive women that received penicillin intravenously during labor or after premature rupture of membranes was compared to controls. Microbiota was analyzed by 16S rRNA sequencing using the PGM Ion Torrent to determine the effects of penicillin use during hospitalization and GBS status on its composition. Penicillin administration was associated with an altered vaginal microbial community composition characterized by increased microbial diversity. Lactobacillus sp. contributed only 13.1% of the total community in the women that received penicillin compared to 88.1% in the controls. Streptococcus sp. were present in higher abundance in GBS positive woman compared to controls, with 60% of the total vaginal microbiota in severe cases identified as Streptococcus sp. Vaginal communities of healthy pregnant women were dominated by Lactobacillus sp. and contained low diversity, while Group B Streptococcus positive women receiving intrapartum antibiotic prophylaxis had a modified vaginal microbiota composition with low abundance of Lactobacillus but higher microbial diversity.

  5. A proposed evidence-based neonatal work-up to confirm or refute allegations of intrapartum asphyxia.

    Science.gov (United States)

    Muraskas, Jonathan K; Morrison, John C

    2010-08-01

    To propose a clinical work-up in term and near-term newborns to address the nine American College of Obstetricians and Gynecologists (the College) and American Academy of Pediatrics criteria to define an acute intrapartum event sufficient to cause cerebral palsy. We examined our experience as neonatal expert witnesses in 103 closed claims of alleged intrapartum asphyxia with poor newborn outcome over a 21-year period from 1987 to 2008. We estimated how often the clinical components of this proposed work-up were not obtained or recorded in the medical record. Cord arterial blood gases and placental pathology were not obtained or sent in 38% and 32% of the 103 cases, respectively. Routine neonatal laboratory tests, including a complete blood count with differential, nucleated red blood cells, electrolytes, calcium, coagulation profile, and renal and liver function tests, were frequently absent. Cranial imaging in ultrasonograms, computed tomography, and magnetic resonance imaging were absent in more than 50% of the cases reviewed and were often not scheduled at optimal times. The medical record of newborns with poor outcomes frequently has a paucity of objective, evidence-based data. This leads to speculation and unethical expert testimony. The protocol will assist in confirming or refuting allegations of intrapartum asphyxia. III.

  6. [The treatment of benign positional paroxysmal vertigo of posterior semicircular canal by Epley maneuver combined with Semont maneuver].

    Science.gov (United States)

    Wang, Tan; An, Fengwei; Xie, Cuili; Chen, Jianqiu; Zhu, Chunsheng; Wang, Ying

    2014-10-01

    To investigate the treatment of benign positional paroxysmal vertigo of posterior semi-circular canal by Epley maneuver combined with Semont maneuver. One hundred and fifty patients with benign positional paroxysmal vertigo of posterior semicircular canal were randomly divided into three groups: group A, B and C. Patients in group A were treated by Epley maneuver and patients in group B were treated by Semont maneuver. Patients in group C were received the treatment of Epley maneuver combined with Semont ma- neuver. We recorded the times of treatments in different groups respectively. Statistics of treatment effects and follow-up studies with 3 months after the recovery were assessed. The cure rate of the canalith repositioning on the primary, secondary and tertiary treatment in group A was respective 72% (38/53) and 81% (43/53) and 85% (45/53), in group B was 68% (30/44) and 80% (35/44) and 84% (37/44), in group C was 89% (47/53) and 94% (50/53) and 98% (52/53). The cure rate in group C is significantly higher than group A and group B (χ2 = 6.777, P positional paroxysmal vertigo of posterior semicircular canal, the primary cure rate was increased and the numbers of treatments were reduced and the relapse was decreased. It is suitable to use Epley maneuver combined with Semont maneuver in the clinic.

  7. Predictors of Women’s Satisfaction with Hospital-Based Intrapartum Care in Asmara Public Hospitals, Eritrea

    Directory of Open Access Journals (Sweden)

    Meron Mehari Kifle

    2017-01-01

    Full Text Available Background. Exploring patient satisfaction contributes to provide quality maternity care, but there is paucity of epidemiologic data in Eritrea. Objectives. To determine the predictors of women's satisfaction with intrapartum care in Asmara public maternity hospitals in Eritrea. Methods. A cross-sectional study among 771 mothers who gave birth in three public Hospitals. Chi-square tests were done to analyze the difference in proportion and logistic regression to assess the predictors of satisfaction with intrapartum care. Results. Overall, only 20.8% of the participants were satisfied with intrapartum service. The key predictors of satisfaction with intrapartum care were provision of clean bed and beddings (AOR = 18.87, 2.33–15.75, privacy during examinations (AOR = 10.22, 4.86–21.48, using understandable language (AOR = 8.72, 3.57–21.27, showing how to summon for help (AOR = 8.16, 4.30–15.48, showing baby immediately after birth (AOR = 8.14, 2.87–23.07, control of the delivery room (AOR = 6.86, 2.65–17.75, receiving back massage (AOR = 6.43, 3.23–12.81, toilet access and cleanliness (AOR = 6.09, 3.25–11.42, availability of chairs for relatives (AOR = 5.96, 3.14–11.30, allowing parents to stay during labour (AOR = 3.52, 1.299–9.56, and request for permission before any procedure (AOR = 2.39, 1.28–4.46. Conclusion. To increase satisfaction with intrapartum care, maternity service providers need to address the general maternity ward cleanliness, improve the quality of physical facilities, and sensitize health providers for better communication with clients. Policy makers need to adopt strategies that ensure more women involvement in decision making and consideration of privacy and reassurance needs during the whole delivery process.

  8. Aqua/Aura Spring 2017 Inclination Adjust Maneuver Series

    Science.gov (United States)

    Noyes, Thomas; Stezelberger, Shane

    2017-01-01

    This will be presented at the International Earth Science Constellation Mission Operations Working Group meeting June 13-15, 2017 to discuss the AquaAura Spring 2017 Inclination Adjust Maneuver series.

  9. Pulsed Electrogasdynamic Thruster for Attitude Control and Orbit Maneuver Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In the Phase I program we successfully demonstrated the feasibility of the Pulsed ElectroGasdynamic (PEG) thruster for attitude control and orbital maneuvering. In...

  10. Time-Optimization of High Performance Combat Maneuvers

    National Research Council Canada - National Science Library

    Carter, Benjamin R

    2005-01-01

    .... High angle of attack maneuvers like the Cobra, Herbst Reversal, and Chakra demonstrate that today's cutting edge fighters are capable of exploiting the post-stall flight regime for very dynamic...

  11. Automated Precision Maneuvering and Landing in Extreme and Constrained Environments

    Data.gov (United States)

    National Aeronautics and Space Administration — Autonomous, precise maneuvering and landing in extreme and constrained environments is a key enabler for future NASA missions. Missions to map the interior of a...

  12. THE DUBINS TRAVELING SALESMAN PROBLEM WITH CONSTRAINED COLLECTING MANEUVERS

    Directory of Open Access Journals (Sweden)

    Petr Váňa

    2016-11-01

    Full Text Available In this paper, we introduce a variant of the Dubins traveling salesman problem (DTSP that is called the Dubins traveling salesman problem with constrained collecting maneuvers (DTSP-CM. In contrast to the ordinary formulation of the DTSP, in the proposed DTSP-CM, the vehicle is requested to visit each target by specified collecting maneuver to accomplish the mission. The proposed problem formulation is motivated by scenarios with unmanned aerial vehicles where particular maneuvers are necessary for accomplishing the mission, such as object dropping or data collection with sensor sensitive to changes in vehicle heading. We consider existing methods for the DTSP and propose its modifications to use these methods to address a variant of the introduced DTSP-CM, where the collecting maneuvers are constrained to straight line segments.

  13. The Space Maneuver Vehicle: Enhancing Space's Utility to the Warfighter

    National Research Council Canada - National Science Library

    Davis, Stephen

    2002-01-01

    ... (the purpose of space control) and lack operational responsiveness. The rapid response, quick turnaround, and high on-orbit maneuverability of the Space Maneuver Vehicle can correct these shortfalls...

  14. Close Proximity Robotic Maneuvering through Flux Pinning Manipulation

    Data.gov (United States)

    National Aeronautics and Space Administration — Non-contacting actuation technology like flux pinning has never been demonstrated in space. The development of a nonphysical joint is critical for maneuvers such as...

  15. Effects-Based Operations: The End of Dominant Maneuver?

    National Research Council Canada - National Science Library

    Cheek, Gary

    2002-01-01

    ... without dominant ground maneuver. The paper concludes that such thinking misreads a historical warfare lethality trend in a potentially dangerous effort to vindicate the Air Force doctrine of strategic attack...

  16. Sinus of Valsalva Aneurysm Rupture: An Unusual Presentation of Chromosome 22q11.2 Deletion: A Case Report

    Directory of Open Access Journals (Sweden)

    Eda-Cristina Abuchaibe

    2012-01-01

    Full Text Available Sinus of Valsalva aneurysm (SVA is defined as a weakness in the aortic valve wall, immediately above the attachments of each of the aortic cusps. This weakness can rupture and create an aortocardiac fistula. There are many congenital heart defects associated with chromosome 22q11 deletion, especially involving the aortic arch and its branches. SVA is not an anomaly usually associated with chromosome 22 deletion. We report the case of a 19-year-old female who presented to our institution with SVA rupture. She was subsequently diagnosed with chromosome 22q11 deletion syndrome. Despite dysmorphic facial features and a learning disability, our patient had not been diagnosed with the chromosome abnormality. SVA is a rare congenital heart defect and has only once previously been reported in a child with a chromosome 22q11 deletion. We report the first case where aneurysm rupture preceded the chromosomal findings. Chromosome 22q11 deletion could be missed due to either the unfamiliarity of physicians with the syndrome or the variability and subtlety of the phenotype. This was demonstrated by our patient who, at age 19 after presenting with an SVA rupture, prompted physicians to find an explanation for her coexisting dysmorphic features and her learning disability.

  17. Initiating Intrapartum Nitrous Oxide in an Academic Hospital: Considerations and Challenges.

    Science.gov (United States)

    Migliaccio, Laura; Lawton, Robyn; Leeman, Lawrence; Holbrook, Amanda

    2017-05-01

    A 50%-50% mixture of nitrous oxide and oxygen has long been used for managing pain during labor in many countries, but only recently has this intrapartum analgesic technique become popular in the United States. Nitrous oxide is considered minimal sedation and a safe pain management alternative. Many facilities are now interested in providing laboring women this analgesic option. The process of establishing use of nitrous oxide in a large institution can be complicated and may seem daunting. This brief report describes the challenges that occurred during the process of initiating nitrous oxide for pain management during childbirth at an academic medical center and discusses various committee roles. Nurses at the University of New Mexico Hospital now directly oversee the administration of nitrous oxide to women in labor in accordance to an established guideline. Despite limited available research, the guideline also allows offering nitrous oxide as a pain management technique for women with opioid dependence. Key components of the guideline and specifics related to education, cost, and safety are reviewed. © 2017 by the American College of Nurse-Midwives.

  18. Intrapartum sacral stress fracture due to pregnancy-related osteoporosis: a case report.

    Science.gov (United States)

    Oztürk, Gülcan; Külcü, Duygu Geler; Aydoğ, Ece

    2013-01-01

    Low back pain (LBP) and hip pain frequently occur during pregnancy and postpartum period. Although pelvic and mechanic lesions of the soft tissues are most responsible for the etiology, sacral fracture is also one of the rare causes. A 32-year-old primigravid patient presented with LBP and right hip pain which started 3 days after vaginal delivery. Although direct radiographic examination was normal, magnetic resonance imaging of the sacrum revealed sacral stress fracture. Lumbar spine and femoral bone mineral density showed osteoporosis as a risk factor. There were no other risk factors such as trauma, excessive weight gain, and strenuous physical activity. It is considered that the patient had sacral fatigue and insufficiency fracture in intrapartum period. The patient's symptoms subsided in 3 months after physical therapy and rest. In conclusion, sacral fractures during pregnancy and postpartum period, especially resulting from childbirth, are very rare. To date, there are two cases in the literature. In cases who even do not have risk factors related to vaginal delivery such as high birth weight infant and the use of forceps, exc., sacral fracture should be considered in the differential diagnosis of LBP and hip pain started soon after child birth. Pregnancy-related osteoporosis may lead to fracture during vaginal delivery.

  19. Intrapartum coccygeal fracture, a cause for postpartum coccydynia: a case report.

    Science.gov (United States)

    Kaushal, Rishi; Bhanot, Arun; Luthra, Shalini; Gupta, P N; Sharma, Raj Bahadur

    2005-01-01

    Coccydynia can result from a varying number of causes, parturition being one of them. Although strains and sprains of the ligaments attached to the coccyx have been thought to be the usual cause for coccydynia occurring after childbirth, an intrapartum coccygeal fracture dislocation can result in the same. A 28-year-old female presented to the orthopaedic department 4 weeks after the birth of her first child with the complaint of coccygeal pain. Examination revealed marked local tenderness over the coccyx but no crepitus was felt. Radiographs established the diagnosis of fracture and posterior dislocation between the second and third coccygeal fragments. Conservative treatment in the form of rest, doughnut ring, local heat, and avoidance of direct pressure over the area resulted in considerable improvement over the next 4 weeks. Coccygeal fracture dislocation may result in introital dyspareunia and tension myalgia of the pelvic floor. Pain from this lesion may become recurrently symptomatic. The diagnosis must be established at the outset and appropriate treatment instituted to avoid these complications.

  20. Effect of intrapartum fetal stress associated with obstetrical interventions on viability and survivability of canine neonates

    Directory of Open Access Journals (Sweden)

    Karthik V. Kuttan

    2016-12-01

    Full Text Available Aim: This study was conducted with the objective of identifying and evaluating intrapartum fetal stress in connection with the type of delivery in bitches. Materials and Methods: A total of 26 bitches between 1 and 5 years, belonging to 10 different breeds were evaluated. Bitches were subjected to detailed clinico-gynecological examination based on history. Neonatal stress associated with spontaneous whelping (SW, assisted whelping (AW, and emergency cesarean section (EC was evaluated using umbilical vein lactate (UL estimation by collecting the blood from umbilical vein. Results: A high umbilical vein lactate value was associated with fetal distress. The mean umbilical lactate value was highest in EC (12.54±0.8 mmol/L followed by AW (8.86±0.9 mmol/L and the lowest value was found in SW (7.56±0.58 mmol/L. A significant increase (p<0.05 in umbilical lactate level was observed in EC group of canine neonates compared with AW and SW groups. Overall mean umbilical lactate values of neonates which died within 24 h (13.31±1.08 mmol/L and the neonates which survived beyond 24 h (8.87±0.55 mmol/L differed significantly at 5% level. Conclusion: Immediate identification of neonatal distress by use of umbilical vein lactate estimation is helpful for the clinician to undertake resuscitation or medical therapy to ensure better neonatal survivability.

  1. Fetal Oropharyngeal and Neck Tumors: Determination of the Need for Ex-Utero Intrapartum Treatment Procedure

    Directory of Open Access Journals (Sweden)

    Fatma Tuncay Özgünen

    2015-06-01

    Full Text Available Background: The aim of this study was to assess the ex-utero intrapartum therapy (EXIT applied to 3 of the 7 cases with oropharyngeal or neck masses and review the indicators of the need for an EXIT procedure. Case Report: Prenatal presentation, size and localization of the masses, existence of fetal hydrops and associated findings such as polyhydramnios, intraoperative managements, complications, and maternal and neonatal outcomes were evaluated through a retrospective analysis. Four cases had neck masses and three cases had oropharyngeal masses. Prenatal sonography was used as the main diagnostic tool for all patients. The median gestational age was 34.5 weeks at the time of diagnosis and 36 weeks at delivery. Polyhydramnios was observed in three of the seven cases and they were delivered prematurely. Interventions such as endotracheal intubation or tracheostomy were performed to provide patency of the airway during delivery by the EXIT procedure in three cases. Hemangioma was found in two cases, teratoma in two cases, lymphangioma in two cases and hamartoma in one case following pathological examination of the masses. Conclusion: The localization of mass, its characteristics, invasion (if it exists, and relation to the airway are the main factors used to determine the need for EXIT. The presence of polyhydramnios may be an important indicator to predict both the need for EXIT and fetal outcomes.

  2. Maintaining Aura's Orbit Requirements Under New Maneuver Operations

    Science.gov (United States)

    Johnson, Megan; Petersen, Jeremy D.

    2014-01-01

    The Earth Observing System (EOS) Afternoon Constellation consists of five member missions (GCOM-W1, Aqua, CALIPSO, CloudSat, and Aura), each of which maintain a frozen, sun-synchronous orbit with a 16-day repeating ground track that follows the Worldwide Reference System-2 (WRS-2). Under nominal science operations for Aura, the propulsion system is oriented such that the resultant thrust vector is aligned 13.493 degrees away from the velocity vector along the yaw axis. When performing orbit maintenance maneuvers, the spacecraft performs a yaw slew to align the thrust vector in the appropriate direction. A new Drag Make Up (DMU) maneuver operations scheme has been implemented for Aura alleviating the need for the 13.493 degree yaw slew. The focus of this investigation is to assess the impact that no-slew DMU maneuver operations will have on Auras Mean Local Time (MLT) which drives the required along track separation between Aura and the constellation members, as well as Auras frozen orbit properties, eccentricity and argument of perigee. Seven maneuver strategies were analyzed to determine the best operational approach. A mirror pole strategy, with maneuvers alternating at the North and South poles, was implemented operationally to minimize impact to the MLT. Additional analysis determined that the mirror pole strategy could be further modified to include frozen orbit maneuvers and thus maintain both MLT and the frozen orbit properties under no-slew operations

  3. Orbital maneuvers around irregular shaped bodies

    Science.gov (United States)

    Venditti, Flaviane; Rocco, E. M.; Almeida Prado, A. B.

    2013-05-01

    Abstract (2,250 Maximum Characters): In the solar system there are many small bodies called asteroids. The large majority of these bodies are located in the asteroid belt, between the orbits of the planets Mars and Jupiter. The Near- Earth Objects, or NEOs, are objects with perihelion below 1.3AU, which include comets and asteroids. The NEOs are considered to have orbits passing close to the Earth’s orbit and, in the case of asteroids, are called Near-Earth Asteroids (NEAs). Among the NEAs there are bodies considered potentially hazardous asteroids (PHAs), whose minimum orbit intersection distance with Earth is 0.05AU and that have absolute magnitude (H) of 22, which would mean an asteroid of at least 110-240 meters, depending on its albedo. One of the major characteristic of the asteroids is the irregular shape, causing the dynamics of orbits around these bodies to be different from a spherical shaped one. The fact that an object is not spherical generates a perturbation on the gravitational field. The disturbing force can be determined considering the shape of the specific body. A satellite orbiting this body would suffer the effects of this perturbation, but knowing the disturbing force, it’s possible to correct and control the orbit according to the desired mission. The polyhedron method is a traditional way to model an asteroid by dividing the object into smaller parts. The data used on this work are composed by a combination of triangular faces. The total disturbing force is a sum of the force on each piece of the model. Therefore, after the simulations are obtained, it’s possible to apply the desired corrections of the perturbation using continuous low thrust in closed loop, making it possible to perform maneuvers near these bodies. One of the important applications of the study shown above is in the ASTER mission, that is under study by INPE and several other Brazilian academic institutions, which goal is to send a spacecraft to an asteroid and then

  4. Antenatal and intrapartum interventions for preventing cerebral palsy: an overview of Cochrane systematic reviews.

    Science.gov (United States)

    Shepherd, Emily; Salam, Rehana A; Middleton, Philippa; Makrides, Maria; McIntyre, Sarah; Badawi, Nadia; Crowther, Caroline A

    2017-08-08

    Cerebral palsy is an umbrella term encompassing disorders of movement and posture, attributed to non-progressive disturbances occurring in the developing fetal or infant brain. As there are diverse risk factors and causes, no one strategy will prevent all cerebral palsy. Therefore, there is a need to systematically consider all potentially relevant interventions for their contribution to prevention. To summarise the evidence from Cochrane reviews regarding the effects of antenatal and intrapartum interventions for preventing cerebral palsy. We searched the Cochrane Database of Systematic Reviews on 7 August 2016, for reviews of antenatal or intrapartum interventions reporting on cerebral palsy. Two authors assessed reviews for inclusion, extracted data, assessed review quality, using AMSTAR and ROBIS, and quality of the evidence, using the GRADE approach. We organised reviews by topic, and summarised findings in text and tables. We categorised interventions as effective (high-quality evidence of effectiveness); possibly effective (moderate-quality evidence of effectiveness); ineffective (high-quality evidence of harm or of lack of effectiveness); probably ineffective (moderate-quality evidence of harm or of lack of effectiveness); and no conclusions possible (low- to very low-quality evidence). We included 15 Cochrane reviews. A further 62 reviews pre-specified the outcome cerebral palsy in their methods, but none of the included randomised controlled trials (RCTs) reported this outcome. The included reviews were high quality and at low risk of bias. They included 279 RCTs; data for cerebral palsy were available from 27 (10%) RCTs, involving 32,490 children. They considered interventions for: treating mild to moderate hypertension (two) and pre-eclampsia (two); diagnosing and preventing fetal compromise in labour (one); preventing preterm birth (four); preterm fetal maturation or neuroprotection (five); and managing preterm fetal compromise (one). Quality of

  5. Impact of Maternal Body Mass Index on Intrapartum and Neonatal Outcomes in Brisbane, Australia, 2007 to 2013.

    Science.gov (United States)

    Foo, Xin Y; Greer, Ristan M; Kumar, Sailesh

    2016-12-01

    The aim of this study was to evaluate the influence of maternal body mass index on intrapartum and neonatal outcomes at one of the largest maternity hospitals in Australia. A retrospective cross-sectional study of 55,352 term singleton deliveries at the Mater Mothers' Hospital in Brisbane, Australia, was conducted. The study cohort was stratified into six groups based on the World Health Organization's body mass index classification. The normal body mass index category was the reference group for all comparisons. Multivariate logistic regression was used to examine the effect of maternal body mass index, adjusted for maternal age, ethnicity, parity, and preexisting conditions (e.g., diabetes mellitus and hypertension), on selected intrapartum and neonatal outcomes. Women in the overweight and Obese I, II, and III categories were more likely to have chronic or gestational hypertension/preeclampsia, and preexisting or gestational diabetes mellitus. They also had an increased risk for induction of labor, elective and emergency cesarean, and postpartum hemorrhage. Underweight women were less likely to require induction of labor and emergency cesarean. Infants born to women with increased body mass index were more likely to require neonatal resuscitation, neonatal intensive care unit admission, and have lower Apgar scores at 5 minutes. There is an increased risk of adverse intrapartum and neonatal outcomes for women who are overweight and obese, with the risks increasing with rising body mass index. Appropriately targeted weight management strategies and health education may yield improved maternal and perinatal outcomes if effectively implemented before pregnancy. These may particularly be of benefit in the teenage cohort that has yet to embark on pregnancy. © 2016 Wiley Periodicals, Inc.

  6. The role of women's attitudinal profiles in satisfaction with the quality of their antenatal and intrapartum care.

    Science.gov (United States)

    Haines, Helen M; Hildingsson, Ingegerd; Pallant, Julie F; Rubertsson, Christine

    2013-07-01

    To compare perceptions of antenatal and intrapartum care in women categorized into three profiles based on attitudes and fear. Prospective longitudinal cohort study using self-report questionnaires. Profiles were constructed from responses to the Birth Attitudes Profile Scale and the Fear of Birth Scale at pregnancy weeks 18 to 20. Perception of the quality of care was measured using the Quality from Patient's Perspective index at 34 to 36 weeks pregnancy and 2 months after birth. Two hospitals in Sweden and Australia. Five hundred and five (505) pregnant women from one hospital in Västernorrland, Sweden (n = 386) and one in northeast Victoria, Australia (n = 123). Women were categorized into three profiles: self-determiners, take it as it comes, and fearful. The self-determiners reported the best outcomes, whereas the fearful were most likely to perceive deficient care. Antenatally the fearful were more likely to indicate deficiencies in medical care, emotional care, support received from nurse-midwives or doctors and nurse-midwives'/doctors' understanding of the woman's situation. They also reported deficiencies in two aspects of intrapartum care: support during birth and control during birth. Attitudinal profiling of women during pregnancy may assist clinicians to deliver the style and content of antenatal and intrapartum care to match what women value and need. An awareness of a woman's fear of birth provides an opportunity to offer comprehensive emotional support with the aim of promoting a positive birth experience. © 2013 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses.

  7. Investigation of piloting aids for manual control of hypersonic maneuvers

    Science.gov (United States)

    Raney, David L.; Phillips, Michael R.; Person, Lee H., Jr.

    1995-01-01

    An investigation of piloting aids designed to provide precise maneuver control for an air-breathing hypersonic vehicle is described. Stringent constraints and nonintuitive high-speed flight effects associated with maneuvering in the hypersonic regime raise the question of whether manual control of such a vehicle should even be considered. The objectives of this research were to determine the extent of manual control that is desirable for a vehicle maneuvering in this regime and to identify the form of aids that must be supplied to the pilot to make such control feasible. A piloted real-time motion-based simulation of a hypersonic vehicle concept was used for this study, and the investigation focused on a single representative cruise turn maneuver. Piloting aids, which consisted of an auto throttle, throttle director, autopilot, flight director, and two head-up display configurations, were developed and evaluated. Two longitudinal control response types consisting of a rate-command/attitude-hold system and a load factor-rate/load-factor-hold system were also compared. The complete set of piloting aids, which consisted of the autothrottle, throttle director, and flight director, improved the average Cooper-Harper flying qualities ratings from 8 to 2.6, even though identical inner-loop stability and control augmentation was provided in all cases. The flight director was determined to be the most critical of these aids, and the cruise turn maneuver was unachievable to adequate performance specifications in the absence of this flight director.

  8. Dynamic cerebral autoregulation changes during sub-maximal handgrip maneuver.

    Directory of Open Access Journals (Sweden)

    Ricardo C Nogueira

    Full Text Available PURPOSE: We investigated the effect of handgrip (HG maneuver on time-varying estimates of dynamic cerebral autoregulation (CA using the autoregressive moving average technique. METHODS: Twelve healthy subjects were recruited to perform HG maneuver during 3 minutes with 30% of maximum contraction force. Cerebral blood flow velocity, end-tidal CO₂ pressure (PETCO₂, and noninvasive arterial blood pressure (ABP were continuously recorded during baseline, HG and recovery. Critical closing pressure (CrCP, resistance area-product (RAP, and time-varying autoregulation index (ARI were obtained. RESULTS: PETCO₂ did not show significant changes during HG maneuver. Whilst ABP increased continuously during the maneuver, to 27% above its baseline value, CBFV raised to a plateau approximately 15% above baseline. This was sustained by a parallel increase in RAP, suggestive of myogenic vasoconstriction, and a reduction in CrCP that could be associated with metabolic vasodilation. The time-varying ARI index dropped at the beginning and end of the maneuver (p<0.005, which could be related to corresponding alert reactions or to different time constants of the myogenic, metabolic and/or neurogenic mechanisms. CONCLUSION: Changes in dynamic CA during HG suggest a complex interplay of regulatory mechanisms during static exercise that should be considered when assessing the determinants of cerebral blood flow and metabolism.

  9. Transesophageal echocardiography in surgical management of pseudoaneurysm of mitral-aortic intervalvular fibrosa with aneurysms of right sinus of Valsalva and left main coronary artery

    Directory of Open Access Journals (Sweden)

    Shreedhar S Joshi

    2013-01-01

    Full Text Available Pseudoaneurysm of mitral-aortic intervalvular fibrosa (MAIVF is a rare complication associated with aortic and/or mitral valve surgery complicated by infective endocarditis. We report pseudoaneurysm of MAIVF in a young adult without overt cardiac disease or previous cardiac surgery. The patient had a rare combination of pseudoaneurysm of MAIVF impinging on anterior mitral leaflet causing moderate mitral regurgitation, right sinus of Valsalva aneurysm extending into interventricular septum, and left main coronary artery aneurysm. Transesophageal echocardiography helped in confirming the lesions, delineating the anatomy of all the lesions, and assessing the adequacy of surgical repair.

  10. Sinus of Valsalva Fistula to the Right Ventricle along with Coronary Artery Fistula to the Pulmonary Artery in a Young Native American Female.

    Science.gov (United States)

    Desai, Sarika; Flores, Erica; Loli, Akil; Maki, Peter

    2013-01-01

    Sinus of Valsalva aneurysm is a rare condition and associated with a high rate of mortality if rupture occurs. The aneurysms are rarely diagnosed until rupture occurs. This case describes a young Native American female whose only symptom was intermittent chest pain prior to the detection of the aneurysm along with a small ventricular septal defect. The patient was also found to have a coexisting coronary artery fistula, and it is rare phenomenon to have these coexisting anomalies. The anomalies were demonstrated on both cardiac computed tomography and coronary angiography. The patient underwent surgical closure of both anomalies, which is the recommended treatment to avoid future complications.

  11. Sinus of Valsalva Fistula to the Right Ventricle along with Coronary Artery Fistula to the Pulmonary Artery in a Young Native American Female

    Directory of Open Access Journals (Sweden)

    Sarika Desai

    2013-01-01

    Full Text Available Sinus of Valsalva aneurysm is a rare condition and associated with a high rate of mortality if rupture occurs. The aneurysms are rarely diagnosed until rupture occurs. This case describes a young Native American female whose only symptom was intermittent chest pain prior to the detection of the aneurysm along with a small ventricular septal defect. The patient was also found to have a coexisting coronary artery fistula, and it is rare phenomenon to have these coexisting anomalies. The anomalies were demonstrated on both cardiac computed tomography and coronary angiography. The patient underwent surgical closure of both anomalies, which is the recommended treatment to avoid future complications.

  12. Morphology, muscle capacity, skill, and maneuvering ability in hummingbirds.

    Science.gov (United States)

    Dakin, Roslyn; Segre, Paolo S; Straw, Andrew D; Altshuler, Douglas L

    2018-02-09

    How does agility evolve? This question is challenging because natural movement has many degrees of freedom and can be influenced by multiple traits. We used computer vision to record thousands of translations, rotations, and turns from more than 200 hummingbirds from 25 species, revealing that distinct performance metrics are correlated and that species diverge in their maneuvering style. Our analysis demonstrates that the enhanced maneuverability of larger species is explained by their proportionately greater muscle capacity and lower wing loading. Fast acceleration maneuvers evolve by recruiting changes in muscle capacity, whereas fast rotations and sharp turns evolve by recruiting changes in wing morphology. Both species and individuals use turns that play to their strengths. These results demonstrate how both skill and biomechanical traits shape maneuvering behavior. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  13. Maneuver Planning for Conjunction Risk Mitigation with Ground-track Control Requirements

    Science.gov (United States)

    McKinley, David

    2008-01-01

    The planning of conjunction Risk Mitigation Maneuvers (RMM) in the presence of ground-track control requirements is analyzed. Past RMM planning efforts on the Aqua, Aura, and Terra spacecraft have demonstrated that only small maneuvers are available when ground-track control requirements are maintained. Assuming small maneuvers, analytical expressions for the effect of a given maneuver on conjunction geometry are derived. The analytical expressions are used to generate a large trade space for initial RMM design. This trade space represents a significant improvement in initial maneuver planning over existing methods that employ high fidelity maneuver models and propagation.

  14. Virtual simulation of maneuvering captive tests for a surface vessel

    Directory of Open Access Journals (Sweden)

    Ahmad Hajivand

    2015-09-01

    Full Text Available Hydrodynamic derivatives or coefficients are required to predict the maneuvering characteristics of a marine vehicle. These derivatives are obtained numerically for a DTMB 5512 model ship by virtual simulating of captive model tests in a CFD environment. The computed coefficients are applied to predict the turning circle and zigzag maneuvers of the model ship. The comparison of the simulated results with the available experimental data shows a very good agreement among them. The simulations show that the CFD is precise and affordable tool at the preliminary design stage to obtain maneuverability performance of a marine vehicles.

  15. Aortic root surgery in Marfan syndrome: Bentall procedure with the composite mechanical valved conduit versus aortic valve reimplantation with Valsalva graft.

    Science.gov (United States)

    Nardi, Paolo; Pellegrino, Antonio; Versaci, Francesco; Mantione, Ludmilla; Polisca, Patrizio; Iorio, Fiore S; Chiariello, Luigi

    2010-09-01

    The aim of the study is to compare mid-term results of Bentall aortic root replacement with composite mechanical valved conduit and aortic valve reimplantation procedure using the Valsalva graft for the treatment of aortic root aneurysm in patients with Marfan syndrome. We retrospectively compared data of 23 patients (mean age 38 + or - 14 years) who had undergone the Bentall procedure (group B) to those of 24 patients (mean age 36 + or - 12 years) who had undergone aortic valve reimplantation (group R) during a 14-year period. Follow-up (mean duration 65 + or - 44 months) was 100% complete. There were no operative deaths in either group. In group B, as compared with group R, preoperative aortic insufficiency (3.2 + or - 1.1/4 vs. 1.7 + or - 1.4/4, P Marfan patients, the Bentall procedure is associated with excellent mid-term outcome. The reimplantation technique, adopted for less dilated aortas, provides similarly satisfactory results. The Valsalva graft seems, with time, to allow a stable aortic valve function.

  16. Acute myocardial infarction due to spontaneous, localized, acute dissection of the sinus of Valsalva detected by intravascular ultrasound and electrocardiogram-gated computed tomography.

    Science.gov (United States)

    Ichihashi, Taku; Ito, Tsuyoshi; Murai, Shunsuke; Ikehara, Noriyuki; Fujita, Hiroshi; Suda, Hisao; Ohte, Nobuyuki

    2016-09-01

    A 58-year-old man was referred to our hospital because of chest pain. The 12-lead electrocardiogram (ECG) revealed ST-segment elevation in II, III, and a Vf with advanced heart block. Transthoracic echocardiography demonstrated aortic root dilatation at the sinus of Valsalva, moderate aortic regurgitation, and decreased wall motion in the inferior part of the left ventricle. Non-ECG-gated enhanced computed tomography (CT) did not reveal an aortic dissection. The patient underwent emergent coronary angiography, which revealed a severely narrowed ostium of the right coronary artery (RCA). Percutaneous coronary intervention (PCI) was performed under intravascular ultrasound (IVUS) guidance. IVUS images demonstrated an intimal flap extending from the aortic wall to the proximal RCA, suggesting that a periaortic hematoma in the false lumen compressed the ostium of the RCA, leading to acute myocardial infarction. To recover hemodynamic stability, the RCA ostium was stented. Subsequent ECG-gated enhanced CT clearly depicted the entry point and extension of the dissection localized within the sinus of Valsalva. The dissection likely involved the left main coronary artery and an emergent Bentall procedure was performed. Intraoperative findings confirmed an intimal tear and extension of the dissection. Thus, ECG-gated CT can clearly depict the entry site and extension of a dissection occurring in the localized area that cannot be detected by conventional CT.

  17. Aqua/Aura Inclination Adjust Maneuver Series Spring 2018 Planning

    Science.gov (United States)

    Trenholme, Elena; Boone, Spencer

    2017-01-01

    This will be presented at the International Earth Science Constellation Mission Operations Working Group meeting on December 6-8, 2017 to discuss the Aqua/Aura Spring 2018 Inclination Adjust Maneuver series planning. Presentation has been reviewed and approved by Eric Moyer, ESMO (Earth Science Mission Operations) Deputy Project Manager.

  18. Cluster-based centralized data fusion for tracking maneuvering ...

    Indian Academy of Sciences (India)

    The interacting multiple model (IMM) algorithm has proved to be useful in tracking maneuvering targets. Tracking accuracy can be further improved using data fusion. Tracking of multiple targets using multiple sensors and fusing them at a central site using centralized architecture involves communication of large volumes of ...

  19. EOS Terra Terra Constellation Exit/Future Maneuver Plans Update

    Science.gov (United States)

    Mantziaras, Dimitrios

    2016-01-01

    This EOS Terra Constellation Exit/Future Maneuver Plans Update presentation will discuss brief history of Terra EOM work; lifetime fuel estimates; baseline vs. proposed plan origin; resultant exit orbit; baseline vs. proposed exit plan; long term orbit altitude; revised lifetime proposal and fallback options.

  20. Astronaut Bruce McCandless tests astronaut maneuvering unit

    Science.gov (United States)

    1973-01-01

    Astronaut Bruce McCandless II, backup pilot for Skylab 2, tests the balance and control of an astronaut maneuvering unit (AMU) test model at Martin Marietta Corporation's Denver division. The jet-powered backpack can fly for 30 minutes and can be worn over normal clothing or space suit.

  1. Cluster-based centralized data fusion for tracking maneuvering ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Abstract. The interacting multiple model (IMM) algorithm has proved to be useful in tracking maneuvering targets. Tracking accuracy can be further improved using data fusion. Tracking of multiple targets using multiple sensors and fusing them at a central site using centralized architecture involves communication of.

  2. Maneuvering and stability performance of a robotic tuna.

    Science.gov (United States)

    Anderson, Jamie M; Chhabra, Narender K

    2002-02-01

    The Draper Laboratory Vorticity Control Unmanned Undersea Vehicle (VCUUV) is the first mission-scale, autonomous underwater vehicle that uses vorticity control propulsion and maneuvering. Built as a research platform with which to study the energetics and maneuvering performance of fish-swimming propulsion, the VCUUV is a self-contained free swimming research vehicle which follows the morphology and kinematics of a yellowfin tuna. The forward half of the vehicle is comprised of a rigid hull which houses batteries, electronics, ballast and hydraulic power unit. The aft section is a freely flooded articulated robot tail which is terminated with a lunate caudal fin. Utilizing experimentally optimized body and tail kinematics from the MIT RoboTuna, the VCUUV has demonstrated stable steady swimming speeds up to 1.2 m/sec and aggressive maneuvering trajectories with turning rates up to 75 degrees per second. This paper summarizes the vehicle maneuvering and stability performance observed in field trials and compares the results to predicted performance using theoretical and empirical techniques.

  3. Proposal for Global Standard Maneuvering Orders for Tugboats

    Directory of Open Access Journals (Sweden)

    Ayumi Ishikura

    2013-12-01

    Full Text Available The use of “Standard Maneuvering Orders” for tugboats, vocabulary and phrases mutually pre-agreed between ships and tugboats, is essential for the former to provide clear direction for the latter when berthing or un-berthing safely. Tugboats will need time to change their posture before they take actions in response to orders from persons responsible for ships’ maneuvering. Therefore, when giving directions to change tugboats’ posture, persons who handle their ships are required to send out tug orders, with regard to “delay time,” a gap be-tween the orders from ships and the actions taken by tugboats. “Tug Orders” standardized and used in Japan are composed of the following three factors concerning towage work: tugboat’s motion, direction and engine power, but the author’s research shows that there are “Non-standard” special maneuvering orders other than those “standardized,” which causes such problems as a gap in perception between pilots and tugboat’s opera-tors, etc. The purpose of this paper is to research the delay time between orders for and actions by tugboats and consider the appropriate and safe timing of providing instructions to them, and then to propose globally-authorized “Standard Maneuvering Orders for tugboats”, discussing a problem involved in the use of the special orders used in Japan, and the way in which tug orders are used in other countries.

  4. Transient Structured Distance as a Maneuver in Marital Therapy

    Science.gov (United States)

    Greene, Bernard L.; And Others

    1973-01-01

    Experience with 73 cases has shown the value of Transient Structured Distance as a maneuver in marriage therapy. While the TSD is a radical form of intervention with risks of anxiety reactions, homosexual panic, or divorce, it has proved effective with difficult forms of acute or chronic marital disharmony. (Author)

  5. Optimizing squatting as a physical maneuver to prevent vasovagal syncope

    NARCIS (Netherlands)

    Krediet, C. T. Paul; Go-Schön, Ingeborg K.; van Lieshout, Johannes J.; Wieling, Wouter

    2008-01-01

    OBJECTIVES: Squatting is a potent physical maneuver to prevent syncope; however, a major drawback is that standing up from squatting is a large hemodynamic stressor that often causes new presyncopal symptoms. We tested the hypothesis that lower body skeletal muscle tensing (LBMT) attenuates the

  6. Relationships among intrapartum maternal fluid intake, birth type, neonatal output, and neonatal weight loss during the first 48 hours after birth.

    Science.gov (United States)

    Lamp, Jane M; Macke, Judi K

    2010-01-01

    To examine predictive relationships among intrapartum maternal fluid intake, birth type, neonatal output, and neonatal weight loss during the first 48 hours after birth. Prospective descriptive design. Women's center of a 900-bed regional acute care facility with 6,700 births per year. A convenience sample of 200 mother/neonate dyads. The Optimality Index of Murphy and Fullerton guided the inclusion and exclusion criteria to ensure healthy dyads. Data collection began in the intrapartum period and concluded with maternal/neonatal discharge. Measures included maternal intrapartum fluid intake from admission to birth, daily neonatal weight, output, and feedings. Data were analyzed via descriptive statistics, tests of significance and multiple regression. Neonatal weight loss was not significantly related to intrapartum maternal fluid intake. Strong predictors of neonatal weight loss and significant weight loss within the first 48 hours were type of feeding (p=.000) and average number of wet diapers (p=.003). Variables predictive of neonatal weight loss can facilitate identification of at-risk neonates to prevent significant weight loss. Close monitoring of the number of wet diapers in the first 48 hours and accurate daily weights at birth time can lead to early detection and preventive interventions.

  7. Intrapartum and neonatal mortality in primary midwife-led and secondary obstetrician-led care in the Amsterdam region of the Netherlands: A retrospective cohort study

    NARCIS (Netherlands)

    Wiegerinck, M. M. J.; van der Goes, B. Y.; Ravelli, A. C. J.; van der Post, J. A. M.; Klinkert, J.; Brandenbarg, J.; Buist, F. C. D.; Wouters, M. G. A. J.; Tamminga, P.; de jonge, A.; Mol, B. W.

    2015-01-01

    To compare intrapartum- and neonatal mortality and intervention rates in term women starting labour in primary midwife-led versus secondary obstetrician-led care. Retrospective cohort study. Amsterdam region of the Netherlands. Women with singleton pregnancies who gave birth beyond 37+0 weeks

  8. The impact of maternal obesity on intrapartum outcomes in otherwise low risk women: secondary analysis of the Birthplace national prospective cohort study

    Science.gov (United States)

    Hollowell, J; Pillas, D; Rowe, R; Linsell, L; Knight, M; Brocklehurst, P

    2014-01-01

    Objectives To evaluate the impact of maternal BMI on intrapartum interventions and adverse outcomes that may influence choice of planned birth setting in healthy women without additional risk factors. Design Prospective cohort study. Setting Stratified random sample of English obstetric units. Sample 17 230 women without medical or obstetric risk factors other than obesity. Methods Multivariable log Poisson regression was used to evaluate the effect of BMI on risk of intrapartum interventions and adverse maternal and perinatal outcomes adjusted for maternal characteristics. Main outcome measures Maternal intervention or adverse outcomes requiring obstetric care (composite of: augmentation, instrumental delivery, intrapartum caesarean section, general anaesthesia, blood transfusion, 3rd/4th degree perineal tear); neonatal unit admission or perinatal death. Results In otherwise healthy women, obesity was associated with an increased risk of augmentation, intrapartum caesarean section and some adverse maternal outcomes but when interventions and outcomes requiring obstetric care were considered together, the magnitude of the increased risk was modest (adjusted RR 1.12, 95% CI 1.02–1.23, for BMI > 35 kg/m2 relative to low risk women of normal weight). Nulliparous low risk women of normal weight had higher absolute risks and were more likely to require obstetric intervention or care than otherwise healthy multiparous women with BMI > 35 kg/m2 (maternal composite outcome: 53% versus 21%). The perinatal composite outcome exhibited a similar pattern. Conclusions Otherwise healthy multiparous obese women may have lower intrapartum risks than previously appreciated. BMI should be considered in conjunction with parity when assessing the potential risks associated with birth in non-obstetric unit settings. PMID:24034832

  9. Maneuver Performance Assessment of the Cassini Spacecraft Through Execution-Error Modeling and Analysis

    Science.gov (United States)

    Wagner, Sean

    2014-01-01

    The Cassini spacecraft has executed nearly 300 maneuvers since 1997, providing ample data for execution-error model updates. With maneuvers through 2017, opportunities remain to improve on the models and remove biases identified in maneuver executions. This manuscript focuses on how execution-error models can be used to judge maneuver performance, while providing a means for detecting performance degradation. Additionally, this paper describes Cassini's execution-error model updates in August 2012. An assessment of Cassini's maneuver performance through OTM-368 on January 5, 2014 is also presented.

  10. Are intrapartum and neonatal deaths in breech delivery at term potentially avoidable?--a blinded controlled audit

    DEFF Research Database (Denmark)

    Krebs, Lone; Langhoff-Roos, Jens; Bødker, Birgit

    2002-01-01

    -92 were studied. For each of the 12 deaths two controls matched by presentation and planned mode of delivery were selected. Eleven obstetricians assessed the care through narratives that ended when the infant was delivered to umbilicus and stated if the infant died, and whether the "possible death......" was potentially avoidable. The majority thought that 42% of cases and 9% of the controls had died. Antenatal and intrapartum care was suboptimal respectively in 17% and 25% of cases and 4% and 26% of controls. The assumed death was found to have been potentially avoidable in 58% of cases and 17% of controls. Care...... in pregnancies with IUGR, pre-eclampsia, placental abruption, post-maturity, the time from decision to performance of cesarean section, and compliance between patient and professionals were more often criticized in cases than in controls. Controlled audit seemed to be a valuable tool for quality improvement...

  11. The expected and actual communication of health care workers during the management of intrapartum: An interpretive multiple case study

    Directory of Open Access Journals (Sweden)

    Doreen K.M. M'Rithaa

    2015-02-01

    Full Text Available Background: Daily activities within a health care organisation are mediated by information communication processes (ICP involving multiple health care professionals at different levels of care. Effective perinatal management requires critical information to be accurately communicated. If there is a breakdown in this communication patient safety is at risk for various reasons such as: inadequate critical information, misconception of information and uninformed decisions being made. The purpose of this study was to interpret the complexities around ICP in order to contribute to the effective management of the intrapartum period.Methods: Multi method, multiple case study approach was used to understand the ICP during the management of the intrapartum period. During the study, the expected ICP, the actual ICP, the challenges involved and the desired ICP were analysed. Twenty-four in-depth interviews with skilled birth attendants (SBAs employing observer-as-participant roles, field notes, and document review methods were utilised to gather the data. Thematic analysis was utilised to analyse the data using Atlas TI software.Results: The study revealed three subthemes which emerged from the expected ICP, whilst three others that emerged formed the theme actual ICP. The subthemes from the expected ICP included: accessibility of obstetric services, expected referral, recommended tools, expected communication and expected documentation. The theme actual ICP held threee merging subthemes: the handover processes, collaborative information seeking, information communicated and referral processes.Conclusion: This study showed that what was expected was not what was actually happening. The requirements of the policies and protocols need to be effectively implemented to improve practice building these into current biomedical guidelines.

  12. Intrapartum and Postpartum Transfers to a Tertiary Care Hospital from Out-of-Hospital Birth Settings: A Retrospective Case Series.

    Science.gov (United States)

    Lundeen, Tiffany

    2016-01-01

    This study describes the reasons for and outcomes of maternal transfers from private homes and freestanding birthing suites to a large academic hospital in order to better understand and meet the needs of transferring women and their families. The convenience sample included all adult women admitted to the labor and birth unit or emergency room within a 5-year period who: 1) had planned to give birth out-of-hospital but developed complications at term before the onset of labor and were admitted to the hospital for labor induction; 2) had planned to give birth at home or in a birthing suite but transferred to the hospital during labor; or 3) arrived at the hospital for care within 24 hours after a planned birth at home or in a birthing suite. Descriptive data for each transfer were obtained from the medical record. Fifty-one transfers were identified: 11 prior to labor, 38 during labor, and 2 postpartum. Only 4 transfers were considered urgent by the referring provider. The most common reasons for intrapartum transfer were prolonged labor (n = 19) and desire for epidural analgesia (n = 10). Only 25% of the medical records had documentation that the referring provider accompanied the woman to the hospital during the care transition or was involved in her hospital course; however, the prenatal and/or intrapartum records had been delivered by the referring provider, were referenced in the hospital admission note, and had become part of the permanent hospital medical record for 85% of the women. On average, one transfer per year was complicated by neonatal morbidity, and one transfer per year involved significant disagreement between hospital providers and the women presenting for care. Collecting and reviewing data about a facility's perinatal transfer events can help the local multi-stakeholder group appraise current practice and plan for quality improvement. © 2016 by the American College of Nurse-Midwives.

  13. Health facility service availability and readiness for intrapartum and immediate postpartum care in Malawi: A cross-sectional survey.

    Directory of Open Access Journals (Sweden)

    Naoko Kozuki

    Full Text Available This analysis seeks to identify strengths and gaps in the existing facility capacity for intrapartum and immediate postpartum fetal and neonatal care, using data collected as a part of Malawi's Helping Babies Breath program evaluation. From August to September 2012, the Maternal and Child Health Integrated Program (MCHIP conducted a cross-sectional survey in 84 Malawian health facilities to capture current health facility service availability and readiness and health worker capacity and practice pertaining to labor, delivery, and immediate postpartum care. The survey collected data on availability of equipment, supplies, and medications, and health worker knowledge and performance scores on intrapartum care simulation and actual management of real clients at a subset of facilities. We ran linear regression models to identify predictors of high simulation performance of routine delivery care and management of asphyxiated newborns across all facilities surveyed. Key supplies for infection prevention and thermal care of the newborn were found to be missing in many of the surveyed facilities. At the health center level, 75% had no clinician trained in basic emergency obstetric care or newborn care and 39% had no midwife trained in the same. We observed that there were no proportional increases in available transport and staff at a facility as catchment population increased. In simulations of management of newborns with breathing problems, health workers were able to complete a median of 10 out of 16 tasks for a full-term birth case scenario and 20 out of 30 tasks for a preterm birth case scenario. Health workers who had more years of experience appeared to perform worse. Our study provides a benchmark and highlights gaps for future evaluations and studies as Malawi continues to make strides in improving facility-based care. Further progress in reducing the burden of neonatal and fetal death in Malawi will be partly predicated on guaranteeing

  14. Is sonographically measured cervical length at 37 weeks of gestation associated with intrapartum cesarean section? A prospective cohort study.

    Science.gov (United States)

    de Vries, Bradley; Narayan, Rajit; McGeechan, Kevin; Santiagu, Stanley; Vairavan, Ramesh; Burke, Minke; Phipps, Hala; Hyett, Jon

    2018-02-16

    Cesarean section rates continue to increase globally. Prediction of intrapartum cesarean section could lead to preventive measures. Our aim was to assess the association between sonographically measured cervical length at 37 weeks of gestation and cesarean section among women planning a vaginal birth. The population was women with a low-risk pregnancy or with gestational diabetes. This was a prospective cohort study conducted in a tertiary referral hospital in Sydney, Australia. In all, 212 women with a low-risk pregnancy or with gestational diabetes were recruited including 158 nulliparous and 54 parous women. Maternal demographic, clinical and ultrasound characteristics were collected at 37 weeks of gestation. Semi-Bayesian logistic regression and Markov chain Monte Carlo simulation were used to assess the relationship between cervical length and cesarean section in labor. Rates of cesarean section were 5% (2/55) for cervical length ≤20 mm, 17% (17/101) for cervical length 20-32 mm, and 27% (13/56) for cervical length >32 mm. These rates were 4, 22 and 33%, respectively, in nulliparous women. In the semi-Bayesian analysis, the odds ratio for cesarean section was 6.2 (95% confidence interval 2.2-43) for cervical length 20-32 mm and 10 (95% confidence interval 4.8-74) for cervical length >32 mm compared with the lowest quartile of cervical length, after adjusting for maternal age, parity, height, prepregnancy body mass index, gestational diabetes, induction of labor, neonatal sex and birthweight centile. Cervical length at 37 weeks of gestation is associated with intrapartum cesarean section. © 2018 Nordic Federation of Societies of Obstetrics and Gynecology.

  15. Thermally-Constrained Fuel-Optimal ISS Maneuvers

    Science.gov (United States)

    Bhatt, Sagar; Svecz, Andrew; Alaniz, Abran; Jang, Jiann-Woei; Nguyen, Louis; Spanos, Pol

    2015-01-01

    Optimal Propellant Maneuvers (OPMs) are now being used to rotate the International Space Station (ISS) and have saved hundreds of kilograms of propellant over the last two years. The savings are achieved by commanding the ISS to follow a pre-planned attitude trajectory optimized to take advantage of environmental torques. The trajectory is obtained by solving an optimal control problem. Prior to use on orbit, OPM trajectories are screened to ensure a static sun vector (SSV) does not occur during the maneuver. The SSV is an indicator that the ISS hardware temperatures may exceed thermal limits, causing damage to the components. In this paper, thermally-constrained fuel-optimal trajectories are presented that avoid an SSV and can be used throughout the year while still reducing propellant consumption significantly.

  16. Orbit Estimation of Non-Cooperative Maneuvering Spacecraft

    Science.gov (United States)

    2015-06-01

    approaches is to determine the percent error of the thrust estimate while the maneuver is occurring. ∆ verr = N∑ i ∣∣∣∣∣∣thtrueai ∣∣∣2 − ∣∣∣thestai ∣∣∣2∣∣∣1...6.4. The ∆ verr error column in Table 6.4 captures the average error in estimating the magnitude of the maneuver after the filter has settled and prior...Cases and Filters Case 1 Case 2 Case 3 Case 4 Case 5 ∆ verr RMS r ∆ verr RMS r ∆ verr RMS r ∆ verr RMS r ∆ verr RMS r EKF 2.1 % 55.1 km 3.9% 61.9 km 20.0

  17. Novel Fractional Order Calculus Extended PN for Maneuvering Targets

    Directory of Open Access Journals (Sweden)

    Jikun Ye

    2017-01-01

    Full Text Available Based on the theory of fractional order calculus (FOC, a novel extended proportional guidance (EPN law for intercepting the maneuvering target is proposed. In the first part, considering the memory function and filter characteristic of FOC, the novel extended PN guidance algorithm is developed based on the conventional PN after introducing the properties and operation rules of FOC. Further, with the help of FOC theory, the average load and ballistics characteristics of proposed guidance law are analyzed. Then, using the small offset kinematic model, the robustness of the new guidance law against autopilot parameters is studied theoretically by analyzing the sensitivity of the closed loop guidance system. At last, representative numerical results show that the designed guidance law obtains a better performance than the traditional PN for maneuvering target.

  18. Real-time optimal guidance for orbital maneuvering.

    Science.gov (United States)

    Cohen, A. O.; Brown, K. R.

    1973-01-01

    A new formulation for soft-constraint trajectory optimization is presented as a real-time optimal feedback guidance method for multiburn orbital maneuvers. Control is always chosen to minimize burn time plus a quadratic penalty for end condition errors, weighted so that early in the mission (when controllability is greatest) terminal errors are held negligible. Eventually, as controllability diminishes, the method partially relaxes but effectively still compensates perturbations in whatever subspace remains controllable. Although the soft-constraint concept is well-known in optimal control, the present formulation is novel in addressing the loss of controllability inherent in multiple burn orbital maneuvers. Moreover the necessary conditions usually obtained from a Bolza formulation are modified in this case so that the fully hard constraint formulation is a numerically well behaved subcase. As a result convergence properties have been greatly improved.

  19. Compressed Sensing ISAR Reconstruction Considering Highly Maneuvering Motion

    Directory of Open Access Journals (Sweden)

    Ahmed Shaharyar Khwaja

    2017-03-01

    Full Text Available In this report, we propose compressed sensing inverse synthetic aperture radar (ISAR imaging in the presence of highly maneuvering motion using a modified orthogonal matching pursuit (OMP reconstruction algorithm. Unlike existing methods where motion is limited to first- or second-order phase terms, we take into account realistic motion of a maneuvering target that can involve a third-order phase term corresponding to the rate of rotational acceleration. In addition, unlike existing fixed dictionary-based methods, which require designing a large dictionary that needs to take into account all of the possible motion parameters, we propose a modified OMP reconstruction method that requires a dictionary only based on the first-order phase term and estimates the secondand third-order phase terms using an optimization algorithm. Simulation examples and comparison with existing methods show the viability of our approach for imaging moving targets consisting of higher order motion.

  20. Evasive Maneuvers in Space Debris Environment and Technological Parameters

    Directory of Open Access Journals (Sweden)

    Antônio D. C. Jesus

    2012-01-01

    Full Text Available We present a study of collisional dynamics between space debris and an operational vehicle in LEO. We adopted an approach based on the relative dynamics between the objects on a collisional course and with a short warning time and established a semianalytical solution for the final trajectories of these objects. Our results show that there are angular ranges in 3D, in addition to the initial conditions, that favor the collisions. These results allowed the investigation of a range of technological parameters for the spacecraft (e.g., fuel reserve that allow a safe evasive maneuver (e.g., time available for the maneuver. The numerical model was tested for different values of the impact velocity and relative distance between the approaching objects.

  1. Conjunction challenges of low-thrust geosynchronous debris removal maneuvers

    Science.gov (United States)

    Anderson, Paul V.; Schaub, Hanspeter

    2016-06-01

    The conjunction challenges of low-thrust engines for continuous thrust re-orbiting of geosynchronous (GEO) objects to super-synchronous disposal orbits are investigated, with applications to end-of-life mitigation and active debris removal (ADR) technologies. In particular, the low maneuverability of low-thrust systems renders collision avoidance a challenging task. This study investigates the number of conjunction events a low-thrust system could encounter with the current GEO debris population during a typical re-orbit to 300 km above the GEO ring. Sensitivities to thrust level and initial longitude and inclination are evaluated, and the impact of delaying the start time for a re-orbiting maneuver is assessed. Results demonstrate that the mean number of conjunctions increases hyperbolically as thrust level decreases, but timing the start of the maneuver appropriately can reduce the average conjunction rate when lower thrust levels are applied.

  2. Sustaining Operational Maneuver in the Twenty-First Century

    Science.gov (United States)

    2010-05-13

    hedgerows while exploiting the breech created by strategic bombers and the other divisions of the United States Army VII Corps. Maneuver operations would...forces encountered the difficult hedgerow obstacles and a tenacious German enemy adapt at defending them. The allied forces lost momentum and needed... hedgerow country.27 For the American forces, it was the transition between the bloody, slow attritional fighting in the Normandy hedgerows and the

  3. Automated Maneuver Design and Checkout for the Lunar Reconnaissance Orbiter

    Science.gov (United States)

    2014-12-01

    Simulink propagator used for maneuver checkout. ............................ 29 Figure 7. S/C orientation evolution for initial problem formulation...you. Fair winds and following seas, and I hope to serve with you once again in the future. xvi THIS PAGE INTENTIONALLY LEFT BLANK 1 I...minimum time problems. While it is possible to develop and apply the necessary conditions to solve any optimal control problem, analysis quickly

  4. Unsteady Aerodynamic Modeling of A Maneuvering Aircraft Using Indicial Functions

    Science.gov (United States)

    2016-03-30

    Paper Undergraduate Student Paper Postgraduate Student Paper █ Unsteady Aerodynamic Modeling of A Maneuvering Aircraft Using Indicial Functions...this configuration exhibit strong pitch up behaviour at a relatively low angle of attack and lateral instability that can lead to serious aerodynamic...reduce flight speed, the reduced flight speed helps to have a smaller radius turn and total travelled time. Next, the airplane starts to roll as the

  5. Analysis of Tactical Automation Requirements for the Maneuver Functional Area.

    Science.gov (United States)

    1987-11-06

    distribucion of information in order to facilitate battlefield decision-making, employment, and sustainment of units below the battalion level. (2...signal node) level within light, airborne, air assault, motorized, and heavy divisions. Signal company command posts normally collocate with one of...Battalion commander. No device allocated. Normally collocated with aviation battalion TOC or maneuver TOC where a device is available. 2. Battalion S2

  6. Unruptured Aneurysm of Sinus of Valsalva Coexisting with the Large Ventricular Septal Defect and Severe Aortic Regurgitation in a Young Man

    Directory of Open Access Journals (Sweden)

    Pouya Nezafati

    2015-01-01

    Full Text Available Introduction. Unruptured sinus of valsalva aneurysm (SVA is a rare congenital anomaly, particularly, when it coexists with a ventricular septal defect (VSD and aortic regurgitation due to the prolapse of the elongated aortic cusp into the VSD. In this report, we present the case of a 19-year-old young man with VSD challenging in spite of dyspnea and lower limb edema. Presentation of Case. Its diagnosis was made on the basis of transthoracic echocardiography results. Surgical management consisted of replacing the SVA with mechanical valve prosthesis. A Gore-Tex patch repaired the VSD. Discussion. In the follow-up periods, clinical and echocardiographic tests showed that the patient was in excellent status. Conclusion. SVA requires a surgical procedure due to its high risk of mortality in unoperated patients and a good safety of surgery.

  7. 296. Aneurisma de Seno de Valsalva no Coronariano Fistulizado a Aurícula Derecha Acompañado de Comunicación Auricular Tipo Ostium Secundum

    Directory of Open Access Journals (Sweden)

    M. García Vieites

    2012-04-01

    Los aneurismas del seno de Valsalva tienen una prevalencia estimada de 0,14%, siendo más comunes en la población masculina. Su localización más frecuente es el seno coronario derecho (70–90%, seguido de seno no coronariano (10–20%, y raramente de seno coronariano izquierdo. Aunque frecuentemente se presentan con defectos congénitos, su asociación con comunicación interauricular es baja. Evolucionan hacia la dilatación progresiva que puede llevar a rotura hacia pericardio o bien fistulizar a cavidades cardíacas. Un diagnóstico e intervención quirúrgica precoz son fundamentales, con una tasa de mortalidad posquirúrgica baja a corto y largo plazo.

  8. Unruptured Aneurysm of Sinus of Valsalva Coexisting with the Large Ventricular Septal Defect and Severe Aortic Regurgitation in a Young Man.

    Science.gov (United States)

    Nezafati, Pouya; Nezafati, Mohammad Hassan; Hoseinikhah, Hamid

    2015-01-01

    Introduction. Unruptured sinus of valsalva aneurysm (SVA) is a rare congenital anomaly, particularly, when it coexists with a ventricular septal defect (VSD) and aortic regurgitation due to the prolapse of the elongated aortic cusp into the VSD. In this report, we present the case of a 19-year-old young man with VSD challenging in spite of dyspnea and lower limb edema. Presentation of Case. Its diagnosis was made on the basis of transthoracic echocardiography results. Surgical management consisted of replacing the SVA with mechanical valve prosthesis. A Gore-Tex patch repaired the VSD. Discussion. In the follow-up periods, clinical and echocardiographic tests showed that the patient was in excellent status. Conclusion. SVA requires a surgical procedure due to its high risk of mortality in unoperated patients and a good safety of surgery.

  9. An Autonomous Onboard Targeting Algorithm Using Finite Thrust Maneuvers

    Science.gov (United States)

    Scarritt, Sara K.; Marchand, Belinda G.; Brown, Aaron J.; Tracy, William H.; Weeks, Michael W.

    2010-01-01

    In earlier investigations, the adaptation and implementation of a modified two-level corrections (or targeting) process as the onboard targeting algorithm for the Trans-Earth Injection phase of Orion is presented. The objective of that targeting algorithm is to generate the times of ignition and magnitudes of the required maneuvers such that the desired state at entry interface is achieved. In an actual onboard flight software implementation, these times of ignition and maneuvers are relayed onto Flight Control for command and execution. Although this process works well when the burn durations or burn arcs are small, this might not be the case during a contingency situation when lower thrust engines are employed to perform the maneuvers. Therefore, a new model for the two-level corrections process is formulated here to accommodate finite burn arcs. This paper presents the development and formulation of the finite burn two-level corrector, used as an onboard targeting algorithm for the Trans-Earth Injection phase of Orion. A performance comparison between the impulsive and finite burn models is also presented. The present formulation ensures all entry constraints are met, without violating the available fuel budget, while allowing for low-thrust scenarios with long burn durations.

  10. Evaluation of Mathematical Models for Tankers’ Maneuvering Motions

    Directory of Open Access Journals (Sweden)

    Erhan AKSU

    2017-03-01

    Full Text Available In this study, the maneuvering performance of two tanker ships, KVLCC1 and KVLCC2 which have different stern forms are predicted using a system-based method. Two different 3 DOF (degrees of freedom mathematical models based on the MMG(Maneuvering Modeling Group concept areappliedwith the difference in representing lateral force and yawing moment by second and third order polynomials respectively. Hydrodynamic coefficients and related parameters used in the mathematical models of the same scale models of KVLCC1 and KVLCC2 ships are estimated by using experimental data of NMRI (National Maritime Research Institute. The simulations of turning circle with rudder angle ±35o , zigzag(±10o /±10o and zigzag (±20o /±20o maneuvers are carried out and compared with free running model test data of MARIN (Maritime Research Institute Netherlands in this study. As a result of the analysis, it can be summarised that MMG model based on the third order polynomial is superior to the one based on the second order polynomial in view of estimation accuracy of lateral hull force and yawing moment.

  11. A Fuel-Efficient Conflict Resolution Maneuver for Separation Assurance

    Science.gov (United States)

    Bowe, Aisha Ruth; Santiago, Confesor

    2012-01-01

    Automated separation assurance algorithms are envisioned to play an integral role in accommodating the forecasted increase in demand of the National Airspace System. Developing a robust, reliable, air traffic management system involves safely increasing efficiency and throughput while considering the potential impact on users. This experiment seeks to evaluate the benefit of augmenting a conflict detection and resolution algorithm to consider a fuel efficient, Zero-Delay Direct-To maneuver, when resolving a given conflict based on either minimum fuel burn or minimum delay. A total of twelve conditions were tested in a fast-time simulation conducted in three airspace regions with mixed aircraft types and light weather. Results show that inclusion of this maneuver has no appreciable effect on the ability of the algorithm to safely detect and resolve conflicts. The results further suggest that enabling the Zero-Delay Direct-To maneuver significantly increases the cumulative fuel burn savings when choosing resolution based on minimum fuel burn while marginally increasing the average delay per resolution.

  12. Capturing and analyzing wheelchair maneuvering patterns with mobile cloud computing.

    Science.gov (United States)

    Fu, Jicheng; Hao, Wei; White, Travis; Yan, Yuqing; Jones, Maria; Jan, Yih-Kuen

    2013-01-01

    Power wheelchairs have been widely used to provide independent mobility to people with disabilities. Despite great advancements in power wheelchair technology, research shows that wheelchair related accidents occur frequently. To ensure safe maneuverability, capturing wheelchair maneuvering patterns is fundamental to enable other research, such as safe robotic assistance for wheelchair users. In this study, we propose to record, store, and analyze wheelchair maneuvering data by means of mobile cloud computing. Specifically, the accelerometer and gyroscope sensors in smart phones are used to record wheelchair maneuvering data in real-time. Then, the recorded data are periodically transmitted to the cloud for storage and analysis. The analyzed results are then made available to various types of users, such as mobile phone users, traditional desktop users, etc. The combination of mobile computing and cloud computing leverages the advantages of both techniques and extends the smart phone's capabilities of computing and data storage via the Internet. We performed a case study to implement the mobile cloud computing framework using Android smart phones and Google App Engine, a popular cloud computing platform. Experimental results demonstrated the feasibility of the proposed mobile cloud computing framework.

  13. An Autonomous Onboard Targeting Algorithm Using Finite Thrust Maneuvers

    Science.gov (United States)

    Scarritt, Sara K.; Marchand, Belinda G.; Weeks, Michael W.

    2009-01-01

    In earlier investigations, the adaptation and implementation of a modified two-level corrections process as the onboard targeting algorithm for the Trans-Earth Injection phase of Orion is presented. The objective of that targeting algorithm is to generate the times of ignition and magnitudes of the required maneuvers such that the desired state at entry interface is achieved. In an actual onboard flight software implementation, these times of ignition and maneuvers are relayed onto Flight Control for command and execution. Although this process works well when the burn durations or burn arcs are small, this might not be the case during a contingency situation when lower thrust engines are employed to perform the maneuvers. Therefore, a new version of the modified two-level corrections process is formulated to handle the case of finite burn arcs. This paper presents the development and formulation of that finite burn modified two-level corrections process which can again be used as an onboard targeting algorithm for the Trans-Earth Injection phase of Orion. Additionally, performance results and a comparison between the two methods are presented. The finite burn two-level corrector formulation presented here ensures the entry constraints at entry interface are still met without violating the available fuel budget, while still accounting for much longer burn times in its design.

  14. Closed-Loop Aerodynamic Flow Control of a Maneuvering Airfoil

    Science.gov (United States)

    Brzozowski, Daniel P.; Culp, John R.; Glezer, Ari

    2011-11-01

    The unsteady interaction between trailing edge aerodynamic flow control and airfoil motion in pitch and plunge is investigated in wind tunnel experiments using a 2-DOF traverse which enables application of time-dependent external torque and forces by servo motors. The global aerodynamic forces and moments are regulated by controlling vorticity generation and accumulation near the surface using hybrid synthetic jet actuators. The dynamic coupling between the actuation and the time-dependent flow field is characterized using simultaneous force and velocity measurements that are taken phase-locked to the commanded actuation waveform. The effect of the unsteady motion on the model-embedded flow control is assessed in unsteady several maneuvers. Circulation time history that is estimated from a PIV wake survey shows that the entire flow over the airfoil readjusts within about 1.5 TCONV, which is about two orders of magnitude shorter than the characteristic time associated with the controlled maneuver of the wind tunnel model. This illustrates that flow-control actuation can be typically effected on time scales that are commensurate with the flow's convective time scale, and that the maneuver response is primarily limited by the inertia of the platform.

  15. Active Control of Aerodynamic Forces on a Rapidly Maneuvering Airfoil

    Science.gov (United States)

    Brzozowski, Daniel; Culp, John; Glezer, Ari

    2009-11-01

    The unsteady aerodynamic forces and moments on a rapidly maneuvering free-moving airfoil are investigated in wind tunnel experiments. The airfoil is mounted on a 2-DOF traverse and its trim and dynamic characteristics are controlled using position and attitude feedback loops that are actuated by servo motors. The motion of the airfoil is effected by bi-directional changes in the pitching moment using controllable trapped vorticity concentrations on both the suction and pressure surfaces near the trailing edge that are induced and regulated by hybrid synthetic jet actuators. The dynamic coupling between the actuation and the time-dependent flow field is characterized using simultaneous force and velocity measurements that are taken phase-locked to the commanded actuation waveform. The unsteady flow characteristics induced by the fluidic actuation during a prescribed maneuver are compared with the effects of a simple rigid-body motion of the airfoil when an external torque is used to achieve a similar maneuver. It is shown that the time-dependent aerodynamic forces and induced flow fields in the near wake of the moving airfoil are significantly different, emphasizing the role of the coupling between the flow control actuation and the model's unsteady aerodynamics.

  16. "Spaghetti Maneuver": A useful tool in pediatric laparoscopy - Our experience

    Directory of Open Access Journals (Sweden)

    Antonio Marte

    2011-01-01

    Full Text Available Aims: The laparoscopic "Spaghetti Maneuver" consists in holding an organ by its extremity with a grasper and rolling it up around the tool to keep the organ stable and facilitate its traction within a small space. We describe our experience with the "Spaghetti Maneuver" in some minimally invasive procedures. Materials and Methods: We successfully adopted this technique in 13 patients (5F : 8M aged between 6 and 14 years (average age, 10 on whom we performed 7 appendectomies, 2 ureteral reimplantation and 4 cholecystectomies. In all cases, after the first steps, the appendix, the gallbladder and the ureter were rolled around the grasper and easily isolated; hemostasis was thus induced and the organ was mobilized until removal during cholecystectomy and appendectomy, and before the reimplantation in case of ureteral reimplantation. Results: We found that this technique facilitated significantly the acts of holding, isolating and removing, when necessary, the structures involved, which remained constantly within the visual field of the operator. This allowed a very ergonomic work setting, overcoming the problem of the "blind" zone, which represents a dangerous and invisible area out of the operator′s control during laparoscopy. Moreover the isolation maneuvers resulted easier and reduced operating time. Conclusion: We think that this technique is easy to perform and very useful, because it facilitates the dissection of these organs, by harmonizing and stabilizing the force of traction exercised.

  17. State Estimation for Landing Maneuver on High Performance Aircraft

    Science.gov (United States)

    Suresh, P. S.; Sura, Niranjan K.; Shankar, K.

    2018-01-01

    State estimation methods are popular means for validating aerodynamic database on aircraft flight maneuver performance characteristics. In this work, the state estimation method during landing maneuver is explored for the first of its kind, using upper diagonal adaptive extended Kalman filter (UD-AEKF) with fuzzy based adaptive tunning of process noise matrix. The mathematical model for symmetrical landing maneuver consists of non-linear flight mechanics equation representing Aircraft longitudinal dynamics. The UD-AEKF algorithm is implemented in MATLAB environment and the states with bias is considered to be the initial conditions just prior to the flare. The measurement data is obtained from a non-linear 6 DOF pilot in loop simulation using FORTRAN. These simulated measurement data is additively mixed with process and measurement noises, which are used as an input for UD-AEKF. Then, the governing states that dictate the landing loads at the instant of touch down are compared. The method is verified using flight data wherein, the vertical acceleration at the aircraft center of gravity (CG) is compared. Two possible outcome of purely relying on the aircraft measured data is highlighted. It is observed that, with the implementation of adaptive fuzzy logic based extended Kalman filter tuned to adapt for aircraft landing dynamics, the methodology improves the data quality of the states that are sourced from noisy measurements.

  18. A rare case of aortic sinuses of valsalva fistula to multiple cardiac chambers secondary to periannular aortic abscess formation from underlying Brucella endocarditis

    Directory of Open Access Journals (Sweden)

    Sabzi, Feridoun

    2015-11-01

    Full Text Available The concomitant presence of abnormal connection from three aortic valsalva sinuses to cardiac chambers is a rare complication of native aortic endocarditis. This case report presents a 37-year-old Iranian female patient who had native aortic valve endocarditis complicated by periannular abscess formation and subsequent perforation to multi-cardiac chambers associated with congestive heart failure and left bundle branch block. Multiple aorto-cavitary fistulas to right atrium, main pulmonary artery, and formation of a pocket over left atrial roof were detected by transthoracic echocardiogram (TTE. She had received a full course of antibiotics therapy in a local hospital and was referred to our center for further surgery. TTE not only detected multiple aorto-cavitary fistulas but also revealed large vegetation in aortic and mitral valve leaflets and also small vegetation in the entrance of fistula to right atrium. However, the tricuspid valve was not involved in infective endocarditis. She underwent open cardiac surgery with double valve replacement with biologic valves and reconstruction of left sinus of valsalva fistula to supra left atrial pocket by pericardial patch repair. The two other fistulas to main pulmonary artery and right atrium were closed via related chambers. The post-operative course was complicated by renal failure and prolonged dependency to ventilator that was managed accordingly with peritoneal dialysis and tracheostomy. The patient was discharged on the 25 day after admission in relatively good condition. The TTE follow-up one year after discharge revealed mild paravalvular leakage in aortic valve position, but the function of mitral valve was normal and no residual fistulas were detected.

  19. An Optimized Method to Detect BDS Satellites' Orbit Maneuvering and Anomalies in Real-Time.

    Science.gov (United States)

    Huang, Guanwen; Qin, Zhiwei; Zhang, Qin; Wang, Le; Yan, Xingyuan; Wang, Xiaolei

    2018-02-28

    The orbital maneuvers of Global Navigation Satellite System (GNSS) Constellations will decrease the performance and accuracy of positioning, navigation, and timing (PNT). Because satellites in the Chinese BeiDou Navigation Satellite System (BDS) are in Geostationary Orbit (GEO) and Inclined Geosynchronous Orbit (IGSO), maneuvers occur more frequently. Also, the precise start moment of the BDS satellites' orbit maneuvering cannot be obtained by common users. This paper presented an improved real-time detecting method for BDS satellites' orbit maneuvering and anomalies with higher timeliness and higher accuracy. The main contributions to this improvement are as follows: (1) instead of the previous two-steps method, a new one-step method with higher accuracy is proposed to determine the start moment and the pseudo random noise code (PRN) of the satellite orbit maneuvering in that time; (2) BDS Medium Earth Orbit (MEO) orbital maneuvers are firstly detected according to the proposed selection strategy for the stations; and (3) the classified non-maneuvering anomalies are detected by a new median robust method using the weak anomaly detection factor and the strong anomaly detection factor. The data from the Multi-GNSS Experiment (MGEX) in 2017 was used for experimental analysis. The experimental results and analysis showed that the start moment of orbital maneuvers and the period of non-maneuver anomalies can be determined more accurately in real-time. When orbital maneuvers and anomalies occur, the proposed method improved the data utilization for 91 and 95 min in 2017.

  20. Associating Crash Avoidance Maneuvers with Driver Attributes and Accident Characteristics: A Mixed Logit Model Approach

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    control maneuvers are considered: “no avoidance maneuvers”, “braking”, “steering”, “braking & steering”, and “other maneuvers”. The importance of avoidance maneuvers derives from the key role of responsible, proactive and state-aware road users within the concept of sustainable safety systems, as well......This study focuses on the propensity of drivers to engage in crash avoidance maneuvers in relation to driver attributes, critical events, crash characteristics, vehicles involved, road characteristics and environmental attributes. Five alternative actions involving emergency lateral and speed...... maneuvers, (iii) fatigue and distractions have a greater negative impact on the tendency to engage in crash avoidance maneuvers than alcohol consumption, (iv) difficult road conditions increase the propensity to perform crash avoidance maneuvers, (v) visual obstruction and artificial illumination have...

  1. Intrapartum intervention rates and perinatal outcomes following induction of labour after 41 + 0 weeks compared to expectant management.

    Science.gov (United States)

    Teo, Elaine Yuzhen; Kumar, Sailesh

    2017-11-01

    There is limited evidence regarding the incidence of intrapartum fetal compromise in women who are induced compared to those managed expectantly. The aim of this study was to investigate intrapartum and perinatal outcomes in women who were induced at >41 + 0 weeks compared to an expectantly managed cohort. This was a retrospective cohort study of singleton, non-anomalous pregnancies delivering between 41 + 0 to 43 + 0 weeks at the Mater Mothers' Hospital, Brisbane. We compared outcomes between women who were induced and those that laboured spontaneously. Six thousand five hundred and one women met the inclusion criteria. Three thousand five hundred and eighty-eight women (55.2%) underwent IOL and 2913 women (44.8%) were managed expectantly. Higher rates of emergency caesarean section (29.4% versus 18.5%, p  41 weeks compared to expectant management results in higher rates of emergency caesarean section mainly due to intrapartum fetal compromise.

  2. Antepartum or intrapartum deinfibulation for childbirth in women with type III female genital mutilation: A systematic review and meta-analysis.

    Science.gov (United States)

    Esu, Ekpereonne; Udo, Atim; Okusanya, Babasola O; Agamse, David; Meremikwu, Martin M

    2017-02-01

    There remains no consensus on the best timing of deinfibulation in women with type III female genital mutilation (FGM). To conduct a systematic review of the effects of antepartum or intrapartum deinfibulation on childbirth outcomes in women with type III FGM. The following major databases were searched: Cochrane Central Register for Controlled Trials (CENTRAL), MEDLINE, Scopus, Web of Science, and ClinicalTrials.gov, from inception until August 2015 without any language restrictions. Studies of pregnant women or girls with type III FGM who were deinfibulated antepartum or intrapartum were included. Two team members independently screened and collected data. Quality of evidence was assessed using GRADE. Summary odds ratios and proportions were calculated when possible. There is no evidence of a significant difference between antepartum and intrapartum deinfibulation for obstetric outcomes such as duration of labor, perineal lacerations, episiotomies, postpartum hemorrhage, and cesarean deliveries. Outcomes in women living with type III FGM and those who have undergone deinfibulation were not statistically different; however, trends show a benefit for deinfibulation. All studies were underpowered to detect statistical differences. Larger studies are required to have full confidence in these findings. CRD42015024464. © 2017 International Federation of Gynecology and Obstetrics. The World Health Organization retains copyright and all other rights in the manuscript of this article as submitted for publication.

  3. The woman, partner and midwife: An integration of three perspectives of labour when intrapartum transfer from a birth centre to a tertiary obstetric unit occurs.

    Science.gov (United States)

    Kuliukas, Lesley J; Hauck, Yvonne C; Lewis, Lucy; Duggan, Ravani

    2017-04-01

    When transfer in labour takes place from a birth centre to a tertiary maternity hospital the woman, her partner and the midwife (the triad) are involved, representing three different perspectives. The purpose of this paper is to explore the integration of these intrapartum transfer experiences for the birth triad. Giorgi's descriptive phenomenological method of analysis was used to explore the 'lived' experiences of Western Australian women, their partners and midwives across the birth journey. Forty-five interviews were conducted. Findings revealed that experiences of intrapartum transfer were unique to each member of the triad (woman, partner and midwife) and yet there were also shared experiences. All three had three themes in common: 'The same journey through three different lenses'; 'In my own world' and 'Talking about the birth'. The woman and partner shared two themes: 'Lost birth dream' and 'Grateful to return to a familiar environment'. The woman and midwife both had: 'Gratitude for continuity of care model' and the partner and midwife both found they were: 'Struggling to adapt to a changing care model' and their 'Inside knowledge was not appreciated'. Insight into the unique integrated experiences during a birth centre intrapartum transfer can inform midwives, empowering them to better support parents through antenatal education before and by offering discussion about the birth and transfer after. Translation of findings to practice also reinforces how midwives can support their colleagues by recognising the accompanying midwife's role and knowledge of the woman. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  4. Cerebroplacental ratio thresholds measured within two weeks of birth and the risk of Cesarean section for intrapartum fetal compromise and adverse neonatal outcome.

    Science.gov (United States)

    N Bligh, Larissa; Alsolai, Amal A; Greer, Ristan M; Kumar, Sailesh

    2017-06-08

    Prediction of intrapartum fetal compromise in uncomplicated, term pregnancies is a global obstetric challenge. Currently, no widely accepted screening test for this condition exists, although the cerebroplacental ratio (CPR) shows promise. We aimed to prospectively evaluate the screening performance of the CPR 10 th centile for detection of Cesarean section for intrapartum fetal compromise (IFC) and composite adverse neonatal outcome (ANO) in low-risk women from 36 weeks and to determine the best CPR threshold from three previously described in the literature. In a blinded, prospective, observational, cohort study, 483 women with uncomplicated singleton pregnancies underwent fortnightly CPR measurement from 36 weeks to delivery and intrapartum and neonatal outcomes were recorded. The CPR 10 th centile threshold screening test performance was calculated for emergency Cesarean section for IFC and composite ANO, incorporating acidosis at birth, Apgar Cesarean section for IFC and 17.9% had a composite ANO. Sensitivity and specificity for CPR Cesarean section IFC and composite ANO, respectively. Comparing the three CPR thresholds, CPR Cesarean section for IFC area under the receiver operating characteristic curve = 0.72, composite ANO area under the receiver operating characteristic curve = 0.58), although its predictive utility was only fair for Cesarean section for IFC and poor for composite ANO. The CPR 10 th centile may be useful as a component of a risk assessment tool for Cesarean section for IFC in low risk pregnancies at term. This article is protected by copyright. All rights reserved.

  5. Maneuver optimization for collision avoidance of LEO objects

    Science.gov (United States)

    Peterson, G.

    Consideration of a maneuver might be warranted when a dangerous conjunction between a primary satellite and a secondary object is identified as part of the collision avoidance (COLA) process. Efficient yet accurate numerical solutions to the maneuver problem have been developed and are implemented in The Aerospace Corporation program DVOPT (DeltaV OPTimization) for objects in geosynchronous orbit. However, achieving an accurate solution for satellites in low Earth (LEO) orbits can be problematic. DVOPT utilizes a two-body backwards/forwards propagation technique to determine the effect a proposed burn has on the probability computation. For high altitude, near-circular orbits such as geosynchronous and semisynchronous (i.e., Global Positioning System), the two-body assumption produces sufficient accuracy. The current research determines the validity of the backwards-forwards two-body propagation and identifies the perturbations that are necessary for regimes other than GEO. It is found that LEO orbits experience a significant effect due to other perturbations, which can disrupt the two -body assumption producing an unacceptable reduction in the accuracy of the probability computation. Earth oblateness and drag influence LEOs. Improvement is made to the DVOPT method by allowing for higher order perturbations in the backwards-forwards propagation. An approximate method is utilized that captures the dominant perturbation characteristics without slowing the solution process significantly. The last point is crucial. During operations, determining viable burn solutions can be time critical. The development of the solution shows that the relative error due to the perturbations can be minimized thereby significantly widening the applicability of the maneuver optimization process to other orbit classes without causing a major increase in the s lutiono runtime.

  6. Self-hypnosis for intrapartum pain management in pregnant nulliparous women: a randomised controlled trial of clinical effectiveness

    Science.gov (United States)

    Downe, S; Finlayson, K; Melvin, C; Spiby, H; Ali, S; Diggle, P; Gyte, G; Hinder, S; Miller, V; Slade, P; Trepel, D; Weeks, A; Whorwell, P; Williamson, M

    2015-01-01

    Objective (Primary) To establish the effect of antenatal group self-hypnosis for nulliparous women on intra-partum epidural use. Design Multi-method randomised control trial (RCT). Setting Three NHS Trusts. Population Nulliparous women not planning elective caesarean, without medication for hypertension and without psychological illness. Methods Randomisation at 28–32 weeks’ gestation to usual care, or to usual care plus brief self-hypnosis training (two × 90-minute groups at around 32 and 35 weeks’ gestation; daily audio self-hypnosis CD). Follow up at 2 and 6 weeks postnatal. Main outcome measures Primary: epidural analgesia. Secondary: associated clinical and psychological outcomes; cost analysis. Results Six hundred and eighty women were randomised. There was no statistically significant difference in epidural use: 27.9% (intervention), 30.3% (control), odds ratio (OR) 0.89 [95% confidence interval (CI): 0.64–1.24], or in 27 of 29 pre-specified secondary clinical and psychological outcomes. Women in the intervention group had lower actual than anticipated levels of fear and anxiety between baseline and 2 weeks post natal (anxiety: mean difference −0.72, 95% CI −1.16 to −0.28, P = 0.001); fear (mean difference −0.62, 95% CI −1.08 to −0.16, P = 0.009) [Correction added on 7 July 2015, after first online publication: ‘Mean difference’ replaced ‘Odds ratio (OR)’ in the preceding sentence.]. Postnatal response rates were 67% overall at 2 weeks. The additional cost in the intervention arm per woman was £4.83 (CI −£257.93 to £267.59). Conclusions Allocation to two-third-trimester group self-hypnosis training sessions did not significantly reduce intra-partum epidural analgesia use or a range of other clinical and psychological variables. The impact of women's anxiety and fear about childbirth needs further investigation. Tweetable abstract Going to 2 prenatal self-hypnosis groups didn't reduce labour epidural use but did

  7. Evaluation of the mobile nurse training (MNT) intervention - a step towards improvement in intrapartum practices in Bihar, India.

    Science.gov (United States)

    Das, Aritra; Nawal, Dipty; Singh, Manoj Kumar; Karthick, Morchan; Pahwa, Parika; Shah, Malay Bharat; Mahapatra, Tanmay; Ranjan, Kunal; Chaudhuri, Indrajit

    2017-08-23

    Evidence shows that improving the quality of intrapartum care is critical for maternal survival. However, a significant rise in the proportion of facility-based births over the last decade in India - attributable to a cash transfer program - has not resulted in a corresponding reduction in maternal mortality, thanks, in part, to low-skilled care at facilities. The current study evaluated a mobile knowledge-based intervention aimed at improving quality of care by mentoring in-service staff nurses at public obstetric facilities. An independent evaluation team conducted baseline and post-intervention assessments at every facility using a mix of methods that included training assessments and Direct Observation of Deliveries. The assessment involved passive observation of pregnant women from the time of their admission at the facility and recording the obstetric events and delivery-related practices on a pre-formatted checklist-based tool. Maternal practices were classified into positive and negative ones and scored. Linear regression analysis was used to evaluate the association of MNT intervention with summary scores for positive, negative and overall practice scores. We evaluated retention of intervention effect by comparing the summary scores at baseline, immediately following intervention and 1 year after intervention. In both unadjusted and adjusted analyses, the intervention was found to be significantly associated with improvement in positive practice score (Unadjusted: parameter estimate (β) = 16.90; 95% confidence interval (CI) = 15.20, 18.60. Adjusted: β = 13.14; 95% CI = 10.97, 15.32). The intervention was also significantly associated with changes in negative practice score, which was reverse coded to represent positive change (Unadjusted: β = 11.66; 95% CI = 10.06, 13.27. Adjusted: β = 2.99; 95% CI = 1.35, 4.63), and overall practice score (Unadjusted: β = 15.74; 95% CI = 14.39, 17.08; Adjusted: β = 10.89; 95% CI = 9.18, 12

  8. Self-hypnosis for intrapartum pain management in pregnant nulliparous women: a randomised controlled trial of clinical effectiveness.

    Science.gov (United States)

    Downe, S; Finlayson, K; Melvin, C; Spiby, H; Ali, S; Diggle, P; Gyte, G; Hinder, S; Miller, V; Slade, P; Trepel, D; Weeks, A; Whorwell, P; Williamson, M

    2015-08-01

    (Primary) To establish the effect of antenatal group self-hypnosis for nulliparous women on intra-partum epidural use. Multi-method randomised control trial (RCT). Three NHS Trusts. Nulliparous women not planning elective caesarean, without medication for hypertension and without psychological illness. Randomisation at 28-32 weeks' gestation to usual care, or to usual care plus brief self-hypnosis training (two × 90-minute groups at around 32 and 35 weeks' gestation; daily audio self-hypnosis CD). Follow up at 2 and 6 weeks postnatal. Primary: epidural analgesia. Secondary: associated clinical and psychological outcomes; cost analysis. Six hundred and eighty women were randomised. There was no statistically significant difference in epidural use: 27.9% (intervention), 30.3% (control), odds ratio (OR) 0.89 [95% confidence interval (CI): 0.64-1.24], or in 27 of 29 pre-specified secondary clinical and psychological outcomes. Women in the intervention group had lower actual than anticipated levels of fear and anxiety between baseline and 2 weeks post natal (anxiety: mean difference -0.72, 95% CI -1.16 to -0.28, P = 0.001); fear (mean difference -0.62, 95% CI -1.08 to -0.16, P = 0.009) [Correction added on 7 July 2015, after first online publication: 'Mean difference' replaced 'Odds ratio (OR)' in the preceding sentence.]. Postnatal response rates were 67% overall at 2 weeks. The additional cost in the intervention arm per woman was £4.83 (CI -£257.93 to £267.59). Allocation to two-third-trimester group self-hypnosis training sessions did not significantly reduce intra-partum epidural analgesia use or a range of other clinical and psychological variables. The impact of women's anxiety and fear about childbirth needs further investigation. © 2015 The Authors. BJOG An International Journal of Obstetrics and Gynaecology published by John Wiley & Sons Ltd on behalf of Royal College of Obstetricians and Gynaecologists.

  9. Birthplace in Australia: Processes and interactions during the intrapartum transfer of women from planned homebirth to hospital.

    Science.gov (United States)

    Fox, Deborah; Sheehan, Athena; Homer, Caroline

    2018-02-01

    the aim of the study was to explore the views and experiences of women, midwives and obstetricians on the intrapartum transfer of women from planned homebirth to hospital in Australia. a Constructivist Grounded Theory approach was taken, to conceptualise the social interactions and processes grounded in the data. urban and regional areas in four states of south-eastern Australia. semi-structured qualitative interviews were conducted with 36 women, midwives and obstetricians who had experienced an intrapartum homebirth transfer within three years prior to the interview. Interviews were audio recorded and transcribed verbatim. women who were transferred to hospital from a planned homebirth made physical and psychological journeys out of their comfort zone, as they faced the uncertainty of changing expectations for their birth. The trusting relationship between a woman and her homebirth midwife was crucial to women's sense of safety and well-being in hospital. Midwives and obstetricians, when congregating in the hospital birthing rooms of transferred women, also felt out of their comfort zones. This was due to the challenges of converging with others who possessed conflicting paradigms of safety and risk in birth that were at odds with their own, and adapting to different routines, roles and responsibilities. These differences were derived from diverse professional, social and personal influences and often manifested in stereotyping behaviours and 'us and them' dynamics. When midwife-woman partnerships were respected as an inclusive part of women's care, collaboration ensued, conflict was ameliorated, and smooth transfers could be celebrated as successes of the maternity care system. supporting woman centred care in homebirth transfers means acknowledging the social challenges of collaborating in the unique context of a transferred woman's hospital birthing room. Understanding the power of the midwife-woman partnership, and its value to the health and well-being of

  10. Measuring the quality and quantity of professional intrapartum support: testing a computerised systematic observation tool in the clinical setting.

    Science.gov (United States)

    Ross-Davie, Mary C; Cheyne, Helen; Niven, Catherine

    2013-08-14

    Continuous support in labour has a significant impact on a range of clinical outcomes, though whether the quality and quantity of support behaviours affects the strength of this impact has not yet been established. To identify the quality and quantity of support, a reliable means of measurement is needed. To this end, a new computerised systematic observation tool, the 'SMILI' (Supportive Midwifery in Labour Instrument) was developed.The aim of the study was to test the validity and usability of the 'Supportive Midwifery in Labour Instrument' (SMILI) and to test the feasibility and acceptability of the systematic observation approach in the clinical intrapartum setting. Systematic observation was combined with a postnatal questionnaire and the collection of data about clinical processes and outcomes for each observed labour.The setting for the study was four National Health Service maternity units in Scotland, UK. Participants in this study were forty five midwives and forty four women.The SMILI was used by trained midwife observers to record labour care provided by midwives. Observations were undertaken for an average of two hours and seventeen minutes during the active first stage of labour and, in 18 cases, the observation included the second stage of labour. Content validity of the instrument was tested by the observers, noting the extent to which the SMILI facilitated the recording of all key aspects of labour care and interactions. Construct validity was tested through exploration of correlations between the data recorded and women's feelings about the support they received. Feasibility and usability data were recorded following each observation by the observer. Internal reliability and construct validity were tested through statistical analysis of the data. One hundred and four hours of labour care were observed and recorded using the SMILI during forty nine labour episodes. The SMILI was found to be a valid and reliable instrument in the intrapartum setting

  11. Effect of width and boundary conditions on meeting maneuvers on two-way separated cycle tracks

    OpenAIRE

    García García, Alfredo; Agustin Gomez, Fernando; Llorca Garcia, Carlos; Angel-Domenech, Antonio

    2015-01-01

    Cycle track design guidelines are rarely based on scientific studies. In the case of off-road two-way cycle tracks, a minimum width must facilitate both passing and meeting maneuvers, being meeting maneuvers the most frequent. This study developed a methodology to observe meeting maneuvers using an instrumented bicycle, equipped with video cameras, a GPS tracker, laser rangefinders and speed sensors. This bicycle collected data on six two-way cycle tracks ranging 13-2.15 m width delimitated b...

  12. Space Shuttle OMS engine valve technology. [Orbital Maneuvering System

    Science.gov (United States)

    Wichmann, H.

    1974-01-01

    Valve technology program to determine shutoff valve concepts suitable for the Orbital Maneuvering System (OMS) engine of the Space Shuttle. The tradeoff studies selected the electric torque motor operated dual poppet and ball valves as the most desirable valve concepts for the OMS Engine Shutoff Valve. A prototype of one of these concepts was built and subjected to a design verification program. A number of unique features were designed to include the required contamination insensitivity, operating fluid compatibility, decontamination capability, minimum maintenance requirement and long service life capability.

  13. Improving aggregate behavior in parking lots with appropriate local maneuvers

    KAUST Repository

    Rodriguez, Samuel

    2013-11-01

    In this paper we study the ingress and egress of pedestrians and vehicles in a parking lot. We show how local maneuvers executed by agents permit them to create trajectories in constrained environments, and to resolve the deadlocks between them in mixed-flow scenarios. We utilize a roadmap-based approach which allows us to map complex environments and generate heuristic local paths that are feasible for both pedestrians and vehicles. Finally, we examine the effect that some agent-behavioral parameters have on parking lot ingress and egress. © 2013 IEEE.

  14. Manned maneuvering unit - A space platform support system

    Science.gov (United States)

    Whitsett, C. E., Jr.; Lenda, J. A.; Josephson, J. T.

    1978-01-01

    The assembly and evaluation of large space platforms in low earth orbit will become practical in the Shuttle era. Extravehicular crewmembers, equipped with manned maneuvering units (MMUs), will play a vital role in the construction and checkout of these platforms. The MMU is a propulsive backpack with mobility extending the crew's visual, mental, and manipulative capabilities beyond the cabin to on-the-spot assembly and maintenance operations. Previous MMU experience is reviewed, Shuttle MMU design features related to space platform support are described, and the use of the MMU for specific construction and assembly tasks is illustrated.

  15. Time-Accurate Calculations of Free-Flight Aerodynamics of Maneuvering Projectiles

    National Research Council Canada - National Science Library

    Sahu, Jubaraj

    2007-01-01

    This paper describes a multidisciplinary computational study undertaken to model the flight trajectories and the free-flight aerodynamics of finned projectiles both with and without control maneuvers...

  16. Diagnostic value of repeated Dix-Hallpike and roll maneuvers in benign paroxysmal positional vertigo

    Directory of Open Access Journals (Sweden)

    Cenk Evren

    Full Text Available Abstract Introduction: Benign Paroxysmal Positional Vertigo (BPPV is the most common peripheral vestibular disorder. The Dix-Hallpike and Roll maneuvers are used to diagnose BPPV. Objective: This study aims to investigate the diagnostic value of repeated Dix-Hallpike and Roll maneuvers in BPPV. Methods: We performed Dix-Hallpike and roll maneuvers in patients who admitted with peripheral vertigo anamnesis and met our criteria. The present study consists of 207 patients ranging in age from 16 to 70 (52.67 ± 10.67. We conducted the same maneuvers sequentially one more time in patients with negative results. We detected patients who had negative results in first maneuver and later developed symptom and nystagmus. We evaluated post-treatment success and patient satisfaction by performing Dizziness Handicap Inventory (DHI at first admittance and two weeks after treatment in all patients with BPPV. Results: Of a total of 207 patients, we diagnosed 139 in first maneuver. We diagnosed 28 more patients in sequentially performed maneuvers. The remaining 40 patients were referred to imaging. There was a significant difference between pre- and post-treatment DHI scores in patients with BPPV (p < 0.001. Conclusion: Performing the diagnostic maneuvers only one more time in vertigo patients in the first clinical evaluation increases the diagnosis success in BPPV. Canalith repositioning maneuvers are effective and satisfactory treatment methods in BPPV.

  17. Orbital Maneuvers Using Low Thrust to Place a Satellite in a Constellation

    Directory of Open Access Journals (Sweden)

    Vivian Martins Gomes

    2007-01-01

    Full Text Available This paper considers the problem of low thrust suboptimal maneuvers to insert a satellite in a constellation. It is assumed that a satellite constellation is given with all the Keplerian elements of the satellite members having known values. Then, it is necessary to maneuver a new satellite from a parking orbit to its position in the constellation. The control available to perform this maneuver is the application of a low thrust to the satellite and the objective is to perform this maneuver with minimum fuel consumption.

  18. Foetal electrocardiograph (ST-analyser or STAN) for intrapartum foetal heart rate monitoring: a friend or a foe?

    Science.gov (United States)

    Chandraharan, Edwin

    2018-01-01

    Cardiotocograph (CTG) is associated with a high false positive rate of up to 60% which may increase the risk of unnecessary intrapartum interventions (emergency caesarean sections or operative vaginal deliveries) without any significant benefits. A recent study on variation of caesarean section rates in England has concluded that there was a very wide variation even in the adjusted rates of caesarean section from 14.9% to 32.1%. Cochrane Systematic Reviews have concluded that the use of FBS does not reduce caesarean section rate or any pre-specified neonatal outcomes. Fetal ECG (ST-Analyser or STAN) has been used in the clinical practice for more than 20 years. Although, initial randomised controlled trials (RCTs) showed great promise regarding the role of STAN in reducing operative delivery rates (instrumental vaginal births and emergency caesarean sections) and neonatal metabolic acidosis, subsequent studies have questioned the role of STAN in clinical practice. A recent meta-analysis which included six randomised controlled trials (a total of 26,446 women) has concluded that there was a 36% reduction in the rate of neonatal metabolic acidosis. Practising clinicians currently face a dilemma as to whether STAN has a place in contemporary obstetric practice or whether it?s use should be discouraged and discontinued.

  19. Issues of informed consent for intrapartum trials: a suggested consent pathway from the experience of the Release trial [ISRCTN13204258

    Directory of Open Access Journals (Sweden)

    Weeks Andrew

    2006-05-01

    Full Text Available Abstract Service users within the NHS are increasingly being asked to participate in clinical research. In Liverpool Women's NHS Foundation Trust, approximately 35% of women take part in research during their pregnancy. For many studies the consent process is simple; information is provided and signed consent is given. There is a difficulty, however, with obtaining informed consent from women in pregnancy who become eligible only when they develop unforeseen complications, especially when they occur acutely. The problem is compounded with women in labour who may be frightened, vulnerable, in pain, under the effect of opiate analgesia, or all of the above. If research to improve the care of these women is to continue, then special consent procedures are needed. These procedures must ensure that the woman's autonomy is protected whilst recognising that women under these circumstances vary enormously, both in their desire for information and their ability to comprehend it. This paper will discuss the obtaining of consent in this situation, and describe an information and consent pathway for intrapartum research which has been developed in collaboration with consumer groups as a way in which these issues can be tackled.

  20. State estimators for tracking sharply-maneuvering ground targets

    Science.gov (United States)

    Visina, Radu S.; Bar-Shalom, Yaakov; Willett, Peter

    2017-05-01

    This paper presents an algorithm, based on the Interacting Multiple Model Estimator, that can be used to track the state of kinematic point targets, moving in two dimensions, that are capable of making sharp heading maneuvers over short periods of time, such as certain ground vehicles moving in an open field. The targets are capable of up to 60 °/s turn rates, while polar measurements are received at 1 Hz. We introduce the Non-Zero Mean, White Noise Turn-Rate IMM (IMM-WNTR) that consists of 3 modes based on a White Noise Turn Rate (WNTR) kinematic model that contains additive, white, Gaussian turn rate process noises. Two of the modes are considered maneuvering modes, and they have opposite (left/right), non-zero mean turn rate input noise. The need for non-zero mean turn rate process noise is explained, and Monte Carlo simulations compare this novel design to the traditional (single-mode) White Noise Acceleration Kalman Filter (WNA KF) and the two-mode White Noise Acceleration/Nearly-Coordinated Turn Rate IMM (IMM-CT). Results show that the IMM-WNTR filter achieves better accuracy and real-time consistency between expected error and actual error as compared to the (single-mode) WNA KF and the IMM-CT in all simulated scenarios, making it a very accurate state estimator for targets with sharp coordinated turn capability in 2D.

  1. A simplex method for the orbit determination of maneuvering satellites

    Science.gov (United States)

    Chen, JianRong; Li, JunFeng; Wang, XiJing; Zhu, Jun; Wang, DanNa

    2018-02-01

    A simplex method of orbit determination (SMOD) is presented to solve the problem of orbit determination for maneuvering satellites subject to small and continuous thrust. The objective function is established as the sum of the nth powers of the observation errors based on global positioning satellite (GPS) data. The convergence behavior of the proposed method is analyzed using a range of initial orbital parameter errors and n values to ensure the rapid and accurate convergence of the SMOD. For an uncontrolled satellite, the orbit obtained by the SMOD provides a position error compared with GPS data that is commensurate with that obtained by the least squares technique. For low Earth orbit satellite control, the precision of the acceleration produced by a small pulse thrust is less than 0.1% compared with the calibrated value. The orbit obtained by the SMOD is also compared with weak GPS data for a geostationary Earth orbit satellite over several days. The results show that the position accuracy is within 12.0 m. The working efficiency of the electric propulsion is about 67% compared with the designed value. The analyses provide the guidance for subsequent satellite control. The method is suitable for orbit determination of maneuvering satellites subject to small and continuous thrust.

  2. How hummingbirds hum: Acoustic holography of hummingbirds during maneuvering flight

    Science.gov (United States)

    Hightower, Ben; Wijnings, Patrick; Ingersoll, Rivers; Chin, Diana; Scholte, Rick; Lentink, David

    2017-11-01

    Hummingbirds make a characteristic humming sound when they flap their wings. The physics and the biological significance of hummingbird aeroacoustics is still poorly understood. We used acoustic holography and high-speed cameras to determine the acoustic field of six hummingbirds while they either hovered stationary in front of a flower or maneuvered to track flower motion. We used a robotic flower that oscillated either laterally or longitudinally with a linear combination of 20 different frequencies between 0.2 and 20 Hz, a range that encompasses natural flower vibration frequencies in wind. We used high-speed marker tracking to dissect the transfer function between the moving flower, the head, and body of the bird. We also positioned four acoustic arrays equipped with 2176 microphones total above, below, and in front of the hummingbird. Acoustic data from the microphones were back-propagated to planes adjacent to the hummingbird to create the first real-time holograms of the pressure field a hummingbird generates in vivo. Integration of all this data offers insight into how hummingbirds modulate the acoustic field during hovering and maneuvering flight.

  3. Braking News: the Link between Crash Severity and Crash Avoidance Maneuvers

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    This study focuses on the linkage between crash severity and crash avoidance maneuvers. Various emergency lateral and speed control maneuvers are considered in response to different critical events that made the crash imminent. Partial proportional odds models are estimated to accommodate the ord...

  4. 32 CFR 552.38 - Acquisition of maneuver agreements for Army commanders.

    Science.gov (United States)

    2010-07-01

    ... Real Estate and Interest Therein § 552.38 Acquisition of maneuver agreements for Army commanders. (a... specific areas desired for use. (b) Real estate coverage. Real estate coverage will be in the form of agreements with landowners, granting the right to conduct maneuvers at a given time or periodically. Short...

  5. 33 CFR 83.34 - Maneuvering and warning signals (Rule 34).

    Science.gov (United States)

    2010-07-01

    ... SECURITY INLAND NAVIGATION RULES RULES Sound and Light Signals § 83.34 Maneuvering and warning signals... propulsion”. (2) Upon hearing the one or two blast signal of the other shall, if in agreement, sound the same... vessel doubts the safety of the proposed maneuver, she shall sound the danger signal specified in...

  6. Cases requiring increased number of repositioning maneuvers in benign paroxysmal positional vertigo

    Directory of Open Access Journals (Sweden)

    Mukadder Korkmaz

    Full Text Available ABSTRACT INTRODUCTION: Benign paroxysmal positional vertigo (BPPV is a clinical syndrome that is proposed to be caused by dislocated utricular debris into semicircular canals. Although the majority of patients are treated by one or two repositioning maneuvers, some of the patients need repeated maneuvers for relief. OBJECTIVE: The goal of this study was to investigate the factors associated with patients with benign paroxysmal positional vertigo who required multiple repositioning procedures for treatment. METHODS: Data were obtained from the clinical records of 153 patients diagnosed with benign paroxysmal positional vertigo. Patients were treated by repositioning maneuvers. Demographic data and the factors including age, sex, canal type, duration of symptoms, comorbidities and number of repositioning maneuvers for relief were documented for statistical analysis. RESULTS: Age, sex, canal type and the duration of symptoms had no impact on the number of maneuvers. The most common comorbidity was spine problems. Hypertension was the only comorbidity that significantly associated with increased number of maneuvers. CONCLUSION: The presence of hypertension is a risk factor for repeated maneuvers in benign paroxysmal positional vertigo treatment. Physicians should be aware of the increased probability of repeated repositioning maneuvers in these group of patients. The role of comorbidities and vascular factors need to be further clarified in the course of benign paroxysmal positional vertigo.

  7. The effects of betahistine in addition to epley maneuver in posterior canal benign paroxysmal positional vertigo.

    Science.gov (United States)

    Guneri, Enis Alpin; Kustutan, Ozge

    2012-01-01

    The purpose of this study is to evaluate the effects of betahistine in addition to Epley maneuver on the quality of life of patients with posterior semicircular canal benign paroxysmal positional vertigo (BPPV) of the canalithiasis type. Double-blind, randomized, controlled clinical trial. Academic university hospital. Seventy-two patients were enrolled in the study. The first group was treated with Epley maneuver only. The second group received placebo drug 2 times daily for 1 week in addition to Epley maneuver, and the third group received 24 mg betahistine 2 times daily for 1 week in addition to Epley maneuver. The effectiveness of the treatments was assessed in each group as well as between them by analyzing and comparing data of 4 different vertigo symptom scales. Epley maneuver, alone or combined with betahistine or placebo, was found to be very effective with a primary success rate of 86.2%. The symptoms were significantly reduced in group 3 patients overall, and those patients younger or older than 50 years of age who had hypertension, with symptom onset <1 month, and with attack duration of less than a minute did significantly better with the combination of betahistine 48 mg daily. Betahistine in addition to Epley maneuver is more effective than Epley maneuver alone or combined with placebo with regard to improvement of symptoms in certain patients. However, future clinical studies covering more patients to investigate the benefit of medical treatments in addition to Epley maneuver are needed.

  8. Cases requiring increased number of repositioning maneuvers in benign paroxysmal positional vertigo.

    Science.gov (United States)

    Korkmaz, Mukadder; Korkmaz, Hakan

    2016-01-01

    Benign paroxysmal positional vertigo (BPPV) is a clinical syndrome that is proposed to be caused by dislocated utricular debris into semicircular canals. Although the majority of patients are treated by one or two repositioning maneuvers, some of the patients need repeated maneuvers for relief. The goal of this study was to investigate the factors associated with patients with benign paroxysmal positional vertigo who required multiple repositioning procedures for treatment. Data were obtained from the clinical records of 153 patients diagnosed with benign paroxysmal positional vertigo. Patients were treated by repositioning maneuvers. Demographic data and the factors including age, sex, canal type, duration of symptoms, comorbidities and number of repositioning maneuvers for relief were documented for statistical analysis. Age, sex, canal type and the duration of symptoms had no impact on the number of maneuvers. The most common comorbidity was spine problems. Hypertension was the only comorbidity that significantly associated with increased number of maneuvers. The presence of hypertension is a risk factor for repeated maneuvers in benign paroxysmal positional vertigo treatment. Physicians should be aware of the increased probability of repeated repositioning maneuvers in these group of patients. The role of comorbidities and vascular factors need to be further clarified in the course of benign paroxysmal positional vertigo. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  9. Applying Dynamical Systems Theory to Optimize Libration Point Orbit Stationkeeping Maneuvers for WIND

    Science.gov (United States)

    Brown, Jonathan M.; Petersen, Jeremy D.

    2014-01-01

    NASA's WIND mission has been operating in a large amplitude Lissajous orbit in the vicinity of the interior libration point of the Sun-Earth/Moon system since 2004. Regular stationkeeping maneuvers are required to maintain the orbit due to the instability around the collinear libration points. Historically these stationkeeping maneuvers have been performed by applying an incremental change in velocity, or (delta)v along the spacecraft-Sun vector as projected into the ecliptic plane. Previous studies have shown that the magnitude of libration point stationkeeping maneuvers can be minimized by applying the (delta)v in the direction of the local stable manifold found using dynamical systems theory. This paper presents the analysis of this new maneuver strategy which shows that the magnitude of stationkeeping maneuvers can be decreased by 5 to 25 percent, depending on the location in the orbit where the maneuver is performed. The implementation of the optimized maneuver method into operations is discussed and results are presented for the first two optimized stationkeeping maneuvers executed by WIND.

  10. 46 CFR 35.20-40 - Maneuvering characteristics-T/OC.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Maneuvering characteristics-T/OC. 35.20-40 Section 35.20-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS OPERATIONS Navigation § 35.20-40 Maneuvering characteristics—T/OC. For each ocean and coastwise tankship of 1,600 gross tons or...

  11. Diagnostic value of repeated Dix-Hallpike and roll maneuvers in benign paroxysmal positional vertigo.

    Science.gov (United States)

    Evren, Cenk; Demirbilek, Nevzat; Elbistanlı, Mustafa Suphi; Köktürk, Füruzan; Çelik, Mustafa

    Benign Paroxysmal Positional Vertigo (BPPV) is the most common peripheral vestibular disorder. The Dix-Hallpike and Roll maneuvers are used to diagnose BPPV. This study aims to investigate the diagnostic value of repeated Dix-Hallpike and Roll maneuvers in BPPV. We performed Dix-Hallpike and roll maneuvers in patients who admitted with peripheral vertigo anamnesis and met our criteria. The present study consists of 207 patients ranging in age from 16 to 70 (52.67±10.67). We conducted the same maneuvers sequentially one more time in patients with negative results. We detected patients who had negative results in first maneuver and later developed symptom and nystagmus. We evaluated post-treatment success and patient satisfaction by performing Dizziness Handicap Inventory (DHI) at first admittance and two weeks after treatment in all patients with BPPV. Of a total of 207 patients, we diagnosed 139 in first maneuver. We diagnosed 28 more patients in sequentially performed maneuvers. The remaining 40 patients were referred to imaging. There was a significant difference between pre- and post-treatment DHI scores in patients with BPPV (pvertigo patients in the first clinical evaluation increases the diagnosis success in BPPV. Canalith repositioning maneuvers are effective and satisfactory treatment methods in BPPV. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  12. Closeup of STS-26 Discovery, OV-103, orbital maneuvering system (OMS) leak

    Science.gov (United States)

    1988-01-01

    Closeup of STS-26 Discovery, Orbiter Vehicle (OV) 103, orbital maneuvering system (OMS) reaction control system (RCS) nitrogen tetroxide gas leak was captured by a Cobra borescope and displayed on a video monitor. The borescope has a miniature videocamera at the end of a flexible rubber tube and is able to be maneuvered into other inaccessible locations.

  13. Associating crash avoidance maneuvers with driver attributes and accident characteristics: a mixed logit model approach

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    from the key role of proactive and state-aware road users within the concept of sustainable safety systems, as well as from the key role of effective corrective maneuvers in the success of automated in-vehicle warning and driver assistance systems. Methods: The analysis is conducted by means of a mixed......Objective: The current study focuses on the propensity of drivers to engage in crash avoidance maneuvers in relation to driver attributes, critical events, crash characteristics, vehicles involved, road characteristics, and environmental conditions. The importance of avoidance maneuvers derives......, (2) women and elderly have a relatively lower propensity to conduct crash avoidance maneuvers, (3) drowsiness and fatigue have a greater negative marginal effect on the tendency to engage in crash avoidance maneuvers than alcohol and drug consumption, (4) difficult road conditions increase...

  14. Time-optimal spacecraft attitude maneuver path planning under boundary and pointing constraints

    Science.gov (United States)

    Wu, Changqing; Xu, Rui; Zhu, Shengying; Cui, Pingyuan

    2017-08-01

    The rapid large angle attitude maneuver capability of spacecraft is required during many space missions. This paper addresses the challenge of time-optimal spacecraft attitude maneuver under boundary and pointing constraints. From the perspective of the optimal time, the constrained attitude maneuver problem is summarized as an optimum path-planning problem. To address this problem, a metaheuristic maneuver path planning method is proposed, Angular velocity-Time Coding Differential Evolution (ATDE). In the ATDE method, the angular velocity and time are coded for attitude maneuver modeling, which increases the number of variables and results in a high-dimensional problem. In order to deal with this problem, differential evolution is employed to perform variation and evolution. The boundary and pointing constraints are constructed into the fitness function for path evaluation. Finally, numerical simulations for the different cases were performed to validate the feasibility and effectiveness of the proposed method.

  15. Helicopter Acoustic Flight Test with Altitude Variation and Maneuvers

    Science.gov (United States)

    Watts, Michael E.; Greenwood, Eric; Sim, Ben; Stephenson, James; Smith, Charles D.

    2016-01-01

    A cooperative flight test campaign between NASA and the U.S. Army was performed from September 2014 to February 2015. The purposes of the testing were to: investigate the effects of altitude variation on noise generation, investigate the effects of gross weight variation on noise generation, establish the statistical variability in acoustic flight testing of helicopters, and characterize the effects of transient maneuvers on radiated noise for a medium-lift utility helicopter. This test was performed at three test sites (0, 4000, and 7000 feet above mean sea level) with two aircraft (AS350 SD1 and EH-60L) tested at each site. This report provides an overview of the test, documents the data acquired and describes the formats of the stored data.

  16. Three axis rotational maneuver and vibration stabilization of elastic spacecraft

    Science.gov (United States)

    Singh, Sahjendra N.

    1987-01-01

    A control law for three-axis rotational maneuvers of a spacecraft beam-tip body configuration based on non-linear inversion and modal velocity feedback is presented. A decoupling attitude control law is presented such that in the closed-loop system the attitude angles of the spacecraft are independently controlled, using the control moments acting on the space vehicle. This controller asymptotically decouples the flexible dynamics from the rigid one and also allows the decomposition of the elastic dynamics into two subsystems representing the transverse deflections of the beam in two orthogonal planes. These low-order subsystems are used for the derivation of a modal velocity feedback stabilizer using the force and moment actuators at the end body. Simulation results are presented to show the capability of the controller.

  17. Non-Toxic Orbital Maneuvering System Engine Development

    Science.gov (United States)

    Green, Christopher; Claflin, Scott; Maeding, Chris; Butas, John

    1999-01-01

    Recent results using the Aestus engine operated with LOx/ethanol propellant are presented. An experimental program at Rocketdyne Propulsion and Power is underway to adapt this engine for the Boeing Reusable Space Systems Division non-toxic Orbital Maneuvering System/Reaction control System (OMS/RCS) system. Daimler-Chrysler Aerospace designed the Aestus as an nitrogen tetroxide/monomethyl hydrazine (NTO/MMH) upper-stage engine for the Ariane 5. The non-toxic OMS/RCS system's preliminary design requires a LOx/ethanol (O2/C2H5OH) engine that operates with a mixture ratio of 1.8, a specific impulse of 323 seconds, and fits within the original OMS design envelope. This paper describes current efforts to meet these requirements including, investigating engine performance using LOx/ethanol, developing the en-ine system sizing package, and meeting the vehicle operation parameters. Data from hot-fire testing are also presented and discussed.

  18. Canalith repositioning in apogeotropic horizontal canal benign paroxysmal positional vertigo: Do we need faster maneuvering?

    Science.gov (United States)

    Hwang, Minho; Kim, Sang-Hoon; Kang, Kyung-Wook; Lee, Dasom; Lee, Sae-Young; Kim, Myeong-Kyu; Lee, Seung-Han

    2015-11-15

    A correct diagnosis and a proper treatment may yield a rapid and simple cure for benign paroxysmal positional vertigo (BPPV). Although the Gufoni maneuver is widely used to treat apogeotropic horizontal-canal BPPV (HC-BPPV), few studies have clarified the relationship between the speed and intensity of maneuver execution and successful canalith reposition. To evaluate the effect of accelerated execution of the Gufoni maneuver, a prospective randomized controlled study was conducted with HC-BPPV patients in a single dizziness clinic. The patients had been diagnosed with apogeotropic HC-BPPV and were undergoing treatment at the dizziness clinic of a tertiary university hospital from January 2013 to August 2014. Two groups were treated with the maneuver performed at different speeds and the resolution rate was compared. The accelerated maneuver group was subjected to faster position changing-within 1s-during the reposition maneuver, while the non-accelerated maneuver group underwent slower maneuvers. Therapeutic efficacy was defined as dizziness relief or resolution of nystagmus within 1h. Fifty patients with apogeotropic HC-BPPV were enrolled and treated with the Gufoni maneuver in two groups of 25 patients. The overall resolution rate was 48% (24 of 50; p=1.00), regardless of acceleration. Our results suggest that a faster, more intense execution of the Gufoni maneuver provides little benefit in treating apogeotropic HC-BPPV. Detachment of the otolith from the cupula or the gravitational force-when the otolith is in the anterior arm of the HC-may be more important contributors to treatment efficacy. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. A Novel Deep Inspiration Maneuver for Difficult Transseptal Puncture.

    Science.gov (United States)

    Aksu, Tolga; Guler, Tumer Erdem; Yalin, Kivanc; Golcuk, Sukriye Ebru; Ozcan, Kazim Serhan; Guler, Niyazi

    2017-02-01

    Transseptal puncture (TSP) may not be possible in cases of an elastic, aneurysmal, or thickened interatrial septum (IAS). During deep inspiration (DI), the chest wall expands and the diaphragm descends. This makes intrapleural pressure to become more negative, which leads to movement of the IAS to the right side. The aim of this study was to verify prospectively the feasibility, safety, and outcome of DI associated with conventional TSP technique in patients with challenging IAS anatomy. From September 2012 to May 2016, 224 patients underwent TSP due to different indications. Patients were divided into 2 groups: 213 patients in whom the left atrium was successfully accessed in 3 attempts were grouped as conventional TSP group and 11 patients in whom left atrium access was failed after 3 conventional attempts were grouped as DI-TSP group. Conventional TSP was successful in 89.6% of patients with the first attempt. Second and third attempts were required in 4.1% and 1.4%, respectively. Septal puncture was achieved at the first attempt in 10 patients within a median of 1 second of DI maneuver (interquartile range, 1 to 3) and without any complications. Challenging IAS anatomy consisting of IAS aneurysm, a thick IAS, and an excessively mobile IAS were more frequent in the DI-TSP group (45% to 8%, 27% to 3%, and 21% to 5%, respectively, p <0.001). In conclusion, TSP by using the DI maneuver may be a reliable and safe method after failed conventional attempts. If there is any doubt about the correct location of the needle, additional imaging modalities have to be used. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Seroprevalence and correlates of HIV, syphilis, and hepatitis B and C virus among intrapartum patients in Kabul, Afghanistan.

    Science.gov (United States)

    Todd, Catherine S; Ahmadzai, Malalay; Atiqzai, Faridullah; Miller, Suellen; Smith, Jeffrey M; Ghazanfar, Syed Alef Shah; Strathdee, Steffanie A

    2008-09-17

    Little current information is available for prevalence of vertically-transmitted infections among the Afghan population. The purpose of this study is to determine prevalence and correlates of human immunodeficiency virus (HIV), syphilis, and hepatitis B and C infection among obstetric patients and model hepatitis B vaccination approaches in Kabul, Afghanistan. This cross-sectional study was conducted at three government maternity hospitals in Kabul, Afghanistan from June through September, 2006. Consecutively-enrolled participants completed an interviewer-administered survey and whole blood rapid testing with serum confirmation for antibodies to HIV, T. pallidum, and HCV, and HBsAg. Descriptive data and prevalence of infection were calculated, with logistic regression used to identify correlates of HBV infection. Modeling was performed to determine impact of current and birth dose vaccination strategies on HBV morbidity and mortality. Among 4452 women, prevalence of HBsAg was 1.53% (95% CI: 1.18 - 1.94) and anti-HCV was 0.31% (95% CI: 0.17 - 0.53). No cases of HIV or syphilis were detected. In univariate analysis, HBsAg was associated with husband's level of education (OR = 1.13, 95% CI: 1.01 - 1.26). Modeling indicated that introduction of birth dose vaccination would not significantly reduce hepatitis-related morbidity or mortality for the measured HBsAg prevalence. Intrapartum whole blood rapid testing for HIV, syphilis, HBV, and HCV was acceptable to patients in Afghanistan. Though HBsAg prevalence is relatively low, periodic assessments should be performed to determine birth dose vaccination recommendations for this setting.

  1. Seroprevalence and correlates of HIV, syphilis, and hepatitis B and C virus among intrapartum patients in Kabul, Afghanistan

    Directory of Open Access Journals (Sweden)

    Ghazanfar Syed

    2008-09-01

    Full Text Available Abstract Background Little current information is available for prevalence of vertically-transmitted infections among the Afghan population. The purpose of this study is to determine prevalence and correlates of human immunodeficiency virus (HIV, syphilis, and hepatitis B and C infection among obstetric patients and model hepatitis B vaccination approaches in Kabul, Afghanistan. Methods This cross-sectional study was conducted at three government maternity hospitals in Kabul, Afghanistan from June through September, 2006. Consecutively-enrolled participants completed an interviewer-administered survey and whole blood rapid testing with serum confirmation for antibodies to HIV, T. pallidum, and HCV, and HBsAg. Descriptive data and prevalence of infection were calculated, with logistic regression used to identify correlates of HBV infection. Modeling was performed to determine impact of current and birth dose vaccination strategies on HBV morbidity and mortality. Results Among 4452 women, prevalence of HBsAg was 1.53% (95% CI: 1.18 – 1.94 and anti-HCV was 0.31% (95% CI: 0.17 – 0.53. No cases of HIV or syphilis were detected. In univariate analysis, HBsAg was associated with husband's level of education (OR = 1.13, 95% CI: 1.01 – 1.26. Modeling indicated that introduction of birth dose vaccination would not significantly reduce hepatitis-related morbidity or mortality for the measured HBsAg prevalence. Conclusion Intrapartum whole blood rapid testing for HIV, syphilis, HBV, and HCV was acceptable to patients in Afghanistan. Though HBsAg prevalence is relatively low, periodic assessments should be performed to determine birth dose vaccination recommendations for this setting.

  2. Does the Janani Suraksha Yojana cash transfer programme to promote facility births in India ensure skilled birth attendance? A qualitative study of intrapartum care in Madhya Pradesh

    Directory of Open Access Journals (Sweden)

    Sarika Chaturvedi

    2015-07-01

    Full Text Available Background: Access to facility delivery in India has significantly increased with the Janani Suraksha Yojana (JSY cash transfer programme to promote facility births. However, a decline in maternal mortality has only followed secular trends as seen from the beginning of the decade well before the programme began. We, therefore, examined the quality of intrapartum care provided in facilities under the JSY programme to study whether it ensures skilled attendance at birth. Design: 1 Non-participant observations (n=18 of intrapartum care during vaginal deliveries at a representative sample of 11 facilities in Madhya Pradesh to document what happens during intrapartum care. 2 Interviews (n=10 with providers to explore reasons for this care. Thematic framework analysis was used. Results: Three themes emerged from the data: 1 delivery environment is chaotic: delivery rooms were not conducive to safe, women-friendly care provision, and coordination between providers was poor. 2 Staff do not provide skilled care routinely: this emerged from observations that monitoring was limited to assessment of cervical dilatation, lack of readiness to provide key elements of care, and the execution of harmful/unnecessary practices coupled with poor techniques. 3 Dominant staff, passive recipients: staff sometimes threatened, abused, or ignored women during delivery; women were passive and accepted dominance and disrespect. Attendants served as ‘go-betweens’ patients and providers. The interviews with providers revealed their awareness of the compromised quality of care, but they were constrained by structural problems. Positive practices were also observed, including companionship during childbirth and women mobilising in the early stages of labour. Conclusions: Our observational study did not suggest an adequate level of skilled birth attendance (SBA. The findings reveal insufficiencies in the health system and organisational structures to provide an

  3. [The influence of airway supporting maneuvers on glottis view in pediatric fiberoptic bronchoscopy].

    Science.gov (United States)

    Umutoglu, Tarik; Gedik, Ahmet Hakan; Bakan, Mefkur; Topuz, Ufuk; Daskaya, Hayrettin; Ozturk, Erdogan; Cakir, Erkan; Salihoglu, Ziya

    2015-01-01

    Flexible fiber optic bronchoscopy is a valuable intervention for evaluation and management of respiratory diseases in both infants, pediatric and adult patients. The aim of this study is to investigate the influence of the airway supporting maneuvers on glottis view during pediatric flexible fiberoptic bronchoscopy. In this randomized, controlled, crossover study; patients aged between 0 and 15 years who underwent flexible fiberoptic bronchoscopy procedure having American Society of Anesthesiologists I-II risk score were included. Patients having risk of difficult intubation, intubated or patients with tracheostomy, and patients with reduced neck mobility or having cautions for neck mobility were excluded from this study. After obtaining best glottic view at the neutral position, patients were positioned jaw trust with open mouth, jaw trust with teeth prottution, head tilt chin lift and triple airway maneuvers and best glottis scores were recorded. Total of 121 pediatric patients, 57 girls and 64 boys, were included in this study. Both jaw trust with open mouth and jaw trust with teeth prottution maneuvers improved the glottis view compared with neutral position (p0.05). Head tilt chin lift and triple airway maneuvers improved glottis view when compared with both jaw trust with open mouth and jaw trust with teeth prottution maneuvers and neutral position (ptriple airway maneuvers (p>0.05). All airway supporting maneuvers improved glottic view during pediatric flexible fiberoptic bronchoscopy; however head tilt chin lift and triple airway maneuvers were found to be the most effective maneuvers. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  4. The influence of airway supporting maneuvers on glottis view in pediatric fiberoptic bronchoscopy.

    Science.gov (United States)

    Umutoglu, Tarik; Gedik, Ahmet Hakan; Bakan, Mefkur; Topuz, Ufuk; Daskaya, Hayrettin; Ozturk, Erdogan; Cakir, Erkan; Salihoglu, Ziya

    2015-01-01

    Flexible fiber optic bronchoscopy is a valuable intervention for evaluation and management of respiratory diseases in both infants, pediatric and adult patients. The aim of this study is to investigate the influence of the airway supporting maneuvers on glottis view during pediatric flexible fiberoptic bronchoscopy. In this randomized, controlled, crossover study; patients aged between 0 and 15 years who underwent flexible fiberoptic bronchoscopy procedure having American Society of Anesthesiologists I-II risk score were included. Patients having risk of difficult intubation, intubated or patients with tracheostomy, and patients with reduced neck mobility or having cautions for neck mobility were excluded from this study. After obtaining best glottic view at the neutral position, patients were positioned jaw trust with open mouth, jaw trust with teeth prottution, head tilt chin lift and triple airway maneuvers and best glottis scores were recorded. Total of 121 pediatric patients, 57 girls and 64 boys, were included in this study. Both jaw trust with open mouth and jaw trust with teeth prottution maneuvers improved the glottis view compared with neutral position (p0.05). Head tilt chin lift and triple airway maneuvers improved glottis view when compared with both jaw trust with open mouth and jaw trust with teeth prottution maneuvers and neutral position (ptriple airway maneuvers (p>0.05). All airway supporting maneuvers improved glottic view during pediatric flexible fiberoptic bronchoscopy; however head tilt chin lift and triple airway maneuvers were found to be the most effective maneuvers. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  5. Statistical study of overvoltages by maneuvering in switches in high voltage using EMTP-RV

    International Nuclear Information System (INIS)

    Dominguez Herrera, Diego Armando

    2013-01-01

    The transient overvoltages produced by maneuvering of switches are studied in a statistical way and through a variation the sequential closing times of switches in networks larger than 230 kV. This study is performed according to time delays and typical deviation ranges, using the tool EMTP- RV (ElectroMagnetic Trasient Program Restructured Version). A conceptual framework related with the electromagnetic transients by maneuver is developed in triphasic switches installed in nominal voltages higher than 230 kV. The methodology established for the execution of statistical studies of overvoltages by switch maneuver is reviewed and evaluated by simulating two fictitious cases in EMTP-RV [es

  6. Effects of automobile steering characteristics on driver/vehicle system performance in discrete maneuvers

    Science.gov (United States)

    Klein, R. H.; Mcruer, D. T.

    1975-01-01

    A series of discrete maneuver tasks were used to evaluate the effects of steering gain and directional mode dynamic parameters on driver/vehicle responses. The importance and ranking of these parameters were evaluated through changes in subjective driver ratings and performance measures obtained from transient maneuvers such as a double lane change, an emergency lane change, and an unexpected obstacle. The unexpected obstacle maneuver proved more sensitive to individual driver differences than to vehicle differences. Results were based on full scale tests with an experienced test driver evaluating many different dynamic configurations plus seventeen ordinary drivers evaluating six key configurations.

  7. A Greedy Search Algorithm for Maneuver-Based Motion Planning of Agile Vehicles

    OpenAIRE

    Neas, Charles Bennett

    2010-01-01

    This thesis presents a greedy search algorithm for maneuver-based motion planning of agile vehicles. In maneuver-based motion planning, vehicle maneuvers are solved offline and saved in a library to be used during motion planning. From this library, a tree of possible vehicle states can be generated through the search space. A depth-first, library-based algorithm called AD-Lib is developed and used to quickly provide feasible trajectories along the tree. AD-Lib combines greedy search tech...

  8. Intrapartum sonography for fetal head asynclitism and transverse position: sonographic signs and comparison of diagnostic performance between transvaginal and digital examination.

    Science.gov (United States)

    Malvasi, Antonio; Stark, Michael; Ghi, Tullio; Farine, Dan; Guido, Marcello; Tinelli, Andrea

    2012-05-01

    The primary goal of this study was to determine the ultrasonographic signs of asynclitic and transverse head positioning. In addition, we compared the performance of intrapartum ultrasound to vaginal digital examination. 150 women were evaluated by 2D transabdominal and translabial ultrasound (US) to detect the asynclitic and deep transverse positions. Transvaginal sterile digital examinations were performed immediately after each intrapartum US assessments, the examinations were repeated at intervals of 45-90 minutes. Examiners were blinded to each other's findings (clinical or sonographic). Data were reviewed and analyzed by an independent reviewer. The efficacy of digital examination was significantly lower than US evaluation for the detection of either transverse position or asynclitism. The most frequent transverse position was the left one, while the most frequent asynclitism was the anterior one. Digital pelvic examination for detection of fetal head transverse position during labor is inferior to US, especially in the deep transverse positioning, where caput succedaneum occurs and reduces the diagnostic accuracy of vaginal digital examination. The US examination leads to early detection of persistent transverse position allowing for earlier timing and optimal technique for the operative vaginal delivery. We describe two signs for diagnosing asynclitism. The "squint sign" and the "sunset of thalamus and cerebellum signs" are two simple US signs allowing detection of anterior and posterior asynclitism.

  9. Microbial profile and characterization of blue bulb manual suction devices used to promote airway clearance in newborns in intrapartum and postpartum units.

    Science.gov (United States)

    O'Neal, Pamela V; Adams, Ellise D; Hanson, Linda A; Damron, N Edward; Alexander, Megan Breland; Zhang, Jie; Leahy, Joseph G

    2017-12-01

    Newborns are suctioned with a blue bulb manual suction device to remove naso-oropharyngeal secretions and promote airway clearance. This study identifies and discusses the microbial profile and characterization of the bulb used in newborns on intrapartum and postpartum units. This was a descriptive study with convenience sampling of a total of 50 bulbs used in cesarean births, vaginal births, and on the postpartum unit. The bulbs were tested for microbial growth, and the percentages of contaminated bulbs were calculated. The χ 2 test was used to compare the proportion of bulbs with microbial growth by route of birth among bulbs sampled from the intrapartum unit. Microbial profile and characterization identified a total of 57 different gram-positive cocci and rods and gram-negative rods. Among 50 bulbs cultured, bacterial growth was present in 42% of the bulbs, and Escherichia coli was identified in 55% of the gram-negative rod isolates. The χ 2 test comparing vaginal and cesarean bulbs showed a statistically significant difference in the percentages of contaminated bulbs for any growth (P = .023) and for any Staphylococcus spp (P = .050). New empirical evidence confirms the bulb is a potential bacterial reservoir and poses a potential health risk for nosocomial infections for newborns. Further studies are needed to identify bacterial transmission, newborn outcomes, bactericidal bulb cleaning methods, and quality and safe suction practices. Copyright © 2017. Published by Elsevier Inc.

  10. The Dix-Hallpike test and the canalith repositioning maneuver.

    Science.gov (United States)

    Viirre, Erik; Purcell, Ian; Baloh, Robert W

    2005-01-01

    The Dix-Hallpike test and the canalith repositioning maneuver (CRM) are used to diagnose and treat benign positional vertigo (BPV). Dix-Hallpike is the standard procedure for diagnosis of BPV, but if the horizontal canal is not tested for BPV and the Dix-Hallpike is only carried out once, the condition may not be diagnosed and appropriately treated. We describe our method of testing for BPV and treating it with CRM. The Dix-Hallpike test involves rapidly moving the patient from a sitting position to "head hanging," where the patient's head is at least 10 degrees below horizontal. This is performed initially for the posterior semicircular canals. If these movements fail to elicit vertigo and nystagmus, tests of the horizontal semicircular canals are performed by laying the patient on each side. Importantly, if there is no vertigo or nystagmus elicited by testing the horizontal semi-circular canals, the posterior semicircular canals are tested again. It appears that being held in the head hanging positions and then left and right lateral positions will often allow the canaliths to collect such that the Dix-Hallpike test will become positive. Failure to repeat the tests of the posterior semicircular canals may result in a falsely negative test. Testing the horizontal canals and repeating the Dix-Hallpike test will reduce the likelihood of patients undergoing extra testing or other consequences of misdiagnosis. If, during any of this testing, a movement elicits vertigo or nystagmus, the appropriate CRM is then carried out.

  11. Tactical approach to maneuvering within the chemical contamination labyrinth

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, T.W. [Department of Energy, Oak Ridge, TN (United States)

    1990-12-31

    The Department of Energy (DOE) recognized the need and accepts the responsibility for understanding the reality and mitigating the consequence of the complex chemical contamination legacy it inherited as well as controlling, reducing, and eliminating extant emissions and effluents. The key to maneuvering through this complicated and multifaceted labyrinth of concerns, from which a meaningful, high quality, and cost-effective restoration/mitigation machine is then set in motions, is the ability to perform accurate, factual, and explicit health and environmental/ecological risk assessments. Likewise, the common denominator for carrying out this essential task is to have access to comprehensive and reliable data of known quality with which to perform those analyses. DOE is committed to identifying the data universe; to technically scrutinize and ensure the quality of that data; to develop efficient and cost-effective means to maximize the handling, utilization, and sharing of that universe; and to undertake those assessments. DOE views this as an effort that can only be accomplished through a merging of the technical excellence that exists within federal and state agencies, academia, and industry. The task at hand is so large that only by integrating that intelligence base can we hope to accomplish the goals of establishing meaningful standards, developing functional and effective solutions, and providing quality guidance at a national scale.

  12. Application of a discretized vortex impulse framework to fish maneuvering

    Science.gov (United States)

    Mendelson, Leah; Techet, Alexandra

    2015-11-01

    In studies of biological propulsion, metrics for quantitative analysis of the vortex wake, including circulation, impulse, and their time derivatives, are a valuable indicator of performance. To better utilize volumetric PIV data in this type of analysis, a discretized method of deriving vortex impulse relying only on velocity data is developed. The impulse formulation is based on the geometry and distribution of circulation along the vortex core line, which can be detected using critical points in the velocity field. This analysis method is then applied to time-resolved velocity data of a turning giant danio (Devario aequipinnatus) and a jumping archer fish (Toxotes microlepis) obtained using Synthetic Aperture PIV (SAPIV). In the case of the danio, the vortex force vector derived from the impulse derivative shows good agreement with the kinematics of the fish tail during the turning maneuver. With the archer fish, the model is used to explore the relationship between the number of tail beats prior to the jump and the jump height.

  13. MEMS Reaction Control and Maneuvering for Picosat Beyond LEO

    Science.gov (United States)

    Alexeenko, Alina

    2016-01-01

    The MEMS Reaction Control and Maneuvering for Picosat Beyond LEO project will further develop a multi-functional small satellite technology for low-power attitude control, or orientation, of picosatellites beyond low Earth orbit (LEO). The Film-Evaporation MEMS Tunable Array (FEMTA) concept initially developed in 2013, is a thermal valving system which utilizes capillary forces in a microchannel to offset internal pressures in a bulk fluid. The local vapor pressure is increased by resistive film heating until it exceeds meniscus strength in a nozzle which induces vacuum boiling and provides a stagnation pressure equal to vapor pressure at that point which is used for propulsion. Interplanetary CubeSats can utilize FEMTA for high slew rate attitude corrections in addition to desaturating reaction wheels. The FEMTA in cooling mode can be used for thermal control during high-power communication events, which are likely to accompany the attitude correction. Current small satellite propulsion options are limited to orbit correction whereas picosatellites are lacking attitude control thrusters. The available attitude control systems are either quickly saturated reaction wheels or movable high drag surfaces with long response times.

  14. Development of Strategy Generator for PWRs Core Maneuver

    International Nuclear Information System (INIS)

    Deswandri

    2003-01-01

    Generally, nuclear power plants are utilized for base-load operation. However, if the nuclear capacity constitutes a large fraction of the total electric capacity in a country, the ability of nuclear power plants to perform load following operation is inevitable. In the load following operation, the reactor power is adjusted based on the fluctuation of electric power demand in the grid. That changes of power level can cause unbalance in the reactor, therefore, the control actions should be done during the power maneuvering. In order that the control actions could be effective and efficient, guidance for the reactor operators is needed. Strategy generator refers to a tool which provides guidance for operators as to control actions to be taken. This work developed the strategy generator based on the three concepts of control strategy. By numerical simulation, performance of these three strategies was tested and compared. The simulation result shows the unique characteristic for each strategy and discussion was provided to evaluate the abilities of each strategy in achieving the control targets. (author)

  15. Steering characteristic of an articulated bus under quasi steady maneuvering

    Science.gov (United States)

    Ubaidillah, Setiawan, Budi Agus; Aridharma, Airlangga Putra; Lenggana, Bhre Wangsa; Caesar, Bernardus Placenta Previo

    2018-02-01

    Articulated buses have been being preferred as public transportation modes due to their operational capacity. Therefore, passenger safety must be the priority of this public service vehicle. This research focused on the analytical approach of steering characteristics of an articulated bus when it maneuvered steadily. Such turning condition could be referred as a stability parameter of the bus for preliminary handling assessment. The analytical approach employed kinematics relationship between front and rear bodies as well as steering capabilities. The quasi steady model was developed to determine steering parameters such as turning radius, oversteer, and understeer. The mathematical model was useful for determining both coefficients of understeer and oversteer. The dimension of articulated bus followed a commonly used bus as utilized in Trans Jakarta busses. Based on the simulation, for one minimum center of the body, the turning radius was calculated about 8.8 m and 7.6 m at steady turning speed of 10 km/h. In neutral condition, the minimum road radius should be 6.5 m at 10 km/h and 6.9 m at 40 km/h. For two centers of the body and oversteer condition, the front body has the turning radius of 8.8 m, while, the rear body has the turning radius of 9.8 m at both turning speeds of 40 km/h. The other steering parameters were discussed accordingly.

  16. On the maneuvering of a flexible space crane

    Science.gov (United States)

    Balas, Mark; Farhat, Charbel; Reisenauer, Brian; Thorwald, Greg

    1990-01-01

    The design of an articulated space crane under NASA's 'Pathfinder' program continues to push forward. However, the large size and extreme flexibility of the crane entail major difficulties in precision positioning. To illustrate this and to gain more insight into its structural dynamic behavior, we have built three-dimensional rigid, flexible, homogenized and non-homogenized finite element models (FEM) of the articulated space crane and simulated its three-dimensional maneuvering. We have also begun to develop control strategies for the flexible system using first a simplified finite element model. The model captures much of the system's low frequency characteristics. From the FEM, a reduced-order model (ROM) based controller is designed based on a specific configuration of the crane. The ROM controller rotates the fixed shape crane about the alpha joint and uses three torque wheels at the tip to actuate its control law. Our analysis of the closed-loop system shows the destabilizing effect of control interaction with unmodeled system dynamics (Controller-Structure-Interaction). Making use of a parallel bank of residual-mode filters (RMF), we are able to compensate for CSI and restore system stability and performance. The implementation of the discrete-time control law on the simplified multi-body model is completed using the SAMCEF code.

  17. The potential role of epigenetic modulations in BPPV maneuver exercises

    Science.gov (United States)

    Tsai, Kun-Ling; Wang, Chia-To; Kuo, Chia-Hua; Cheng, Yuan-Yang; Ma, Hsin-I; Hung, Ching-Hsia; Tsai, Yi-Ju; Kao, Chung-Lan

    2016-01-01

    Benign paroxysmal positional vertigo (BPPV) is one of the most common complaints encountered in clinics and is strongly correlated with advanced age or, possibly, degeneration. Redistribution exercises are the most effective approaches to treat BPPV, and canalith repositioning procedure (CRP) cure most BPPV cases. However, the mechanisms through which the treatment modulates systemic molecules in BPPV patients remain largely unknown. In this study, we report that the miR-34a and Sirtuin 1 (SIRT1) genes correlated with the treatment effects of CRP in BPPV subjects. We found that miR-34a expression was largely inhibited and SIRT1 expression was significantly reversed after BPPV maneuver treatment. We also confirmed that the PPAR-γ, PGC-1 and FoxO gene expressions were decreased immediately after canalith repositioning procedure (CRP) for BPPV, and were largely increased after a complete cure of BPPV. Moreover, we observed that after a complete recovery of BPPV, the ROS concentrations, pro-inflammatory cytokine concentrations and p53 expression levels were attenuated. We conclude that BPPV treatment might involve some epigenetic regulations through the mediation of miR-34a, SIRT1 functions and repression of redox status. PMID:27203679

  18. Motion Planning for Bipedal Robot to Perform Jump Maneuver

    Directory of Open Access Journals (Sweden)

    Xinyang Jiang

    2018-01-01

    Full Text Available The remarkable ability of humans to perform jump maneuvers greatly contributes to the improvements of the obstacle negotiation ability of humans. The paper proposes a jumping control scheme for a bipedal robot to perform a high jump. The half-body of the robot is modeled as three planar links and the motion during the launching phase is taken into account. A geometrically simple motion was first conducted through which the gear reduction ratio that matches the maximum motor output for high jumping was selected. Then, the following strategies to further exploit the motor output performance was examined: (1 to set the maximum torque of each joint as the baseline that is explicitly modeled as a piecewise linear function dependent on the joint angular velocity; (2 to exert it with a correction of the joint angular accelerations in order to satisfy some balancing criteria during the motion. The criteria include the location of ZMP (zero moment point and the torque limit. Using the technique described above, the jumping pattern is pre-calculated to maximize the jump height. Finally, the effectiveness of the proposed method is evaluated through simulations. In the simulation, the bipedal robot model achieved a 0.477-m high jump.

  19. A safe-repositioning maneuver for the management of benign paroxysmal positional vertigo: Gans vs. Epley maneuver; a randomized comparative clinical trial.

    Science.gov (United States)

    Saberi, Alia; Nemati, Shadman; Sabnan, Salah; Mollahoseini, Fatemeh; Kazemnejad, Ehsan

    2017-08-01

    Benign paroxysmal positional vertigo (BPPV) is the most common cause of peripheral vertigo. Some repositioning maneuvers have been described for its management. The aim of this study was comparing the therapeutic effect of Epley and Gans maneuvers in BPPV. This randomized clinical trial was performed from September to December 2015. 73 patients with true vertigo diagnosed as BPPV enrolled the study. They randomly assigned in quadripartite blocks to modified Epley maneuver group (E) or Gans maneuver group (G). 1 day and 1 week after intervention, the objective and subjective responses to treatment were assessed. Statistical analysis was performed using the Chi-square test and regression model in the SPSS software version 21. Thirty patients enrolled each group with a mean age of 46.9 ± 13.4 (E group) and 46.7 ± 7.5 year (G group). 23.3 % of E group and 26.7 % of G group were men (p = 0.766). In E and G groups in the first day, subjective outcomes revealed 86.7 and 60 % rate of success (p = 0.02); and 86.7 and 56.7 % of patients exhibited objective improvement, respectively (p = 0.01). After 1 week, the subjective and objective outcomes revealed improvement among 70 % of E group and 46.7 % of G group (p = 0.067). The only complication with significant difference was cervical pain with a higher rate in E group (23.3 vs. 0.0 %, p = 0.005). These results revealed the similar long-term efficacy of Epley and Gans maneuver for the treatment of BPPV. Cervical pain was most frequent complication of Epley maneuver.

  20. Importance of back blow maneuvers in a 6 month old patient with sudden upper airway obstruction

    Directory of Open Access Journals (Sweden)

    Pinar Gencpinar

    2015-12-01

    Full Text Available Foreign body aspiration in children under four years old is one of the most frequently observed reasons for accident related deaths. It is more common in this age group due to inadequate swallowing functions and exploration of objects with the mouth. The most frequently encountered foreign bodies are food and toy parts. Life threatening complete laryngeal obstruction is rarely observed. Dyspnea, hypersalivation, cough and cyanosis can be seen. The basic and life-saving treatment approach is complete removal of foreign body maneuvers in the sudden onset of total obstruction. Here we report a six-month old male, who ingested a foreign body and was treated with back blow maneuvers successfully. In this case we emphasized the importance of back blow maneuvers. Keywords: Upper airway obstruction, Child, Back blows maneuvers

  1. Efficacy of Epley’s Maneuver in Treating BPPV Patients: A Prospective Observational Study

    Directory of Open Access Journals (Sweden)

    Sushil Gaur

    2015-01-01

    Full Text Available Vertigo and balance disorders are among the most common symptoms encountered in patients who visit ENT outpatient department. This is associated with risk of falling and is compounded in elderly persons with other neurologic deficits and chronic medical problems. BPPV is the most common cause of peripheral vertigo. BPPV is a common vestibular disorder leading to significant morbidity, psychosocial impact, and medical costs. The objective of Epley’s maneuver, which is noninvasive, inexpensive, and easily administered, is to move the canaliths out of the canal to the utricle where they no longer affect the canal dynamics. Our study aims to analyze the response to Epley’s maneuver in a series of patients with posterior canal BPPV and compares the results with those treated exclusively by medical management alone. Even though many studies have been conducted to prove the efficacy of this maneuver, this study reinforces the validity of Epley’s maneuver by comparison with the medical management.

  2. Development of a Ground Vehicle Maneuver Ontology to Support the Common Operational Picture

    National Research Council Canada - National Science Library

    Richmond, Paul W; Blais, Curtis L; Goerger, Niki C

    2006-01-01

    .... This paper describes both the Mobility-COP, from which warfighters can assess the ability of forces to maneuver effectively under multiple environmental and tactical conditions, and a formal ontology...

  3. The Effects of Natural Locomotion on Maneuvering Task Performance in Virtual and Real Environments

    National Research Council Canada - National Science Library

    Unguder, Eray

    2001-01-01

    This thesis investigates human performance differences on maneuvering tasks in virtual and real spaces when a natural locomotion technique is used as opposed to an abstraction through a device such as a...

  4. A Computer Simulation of the System-Wide Effects of Parallel-Offset Route Maneuvers

    Science.gov (United States)

    Lauderdale, Todd A.; Santiago, Confesor; Pankok, Carl

    2010-01-01

    Most aircraft managed by air-traffic controllers in the National Airspace System are capable of flying parallel-offset routes. This paper presents the results of two related studies on the effects of increased use of offset routes as a conflict resolution maneuver. The first study analyzes offset routes in the context of all standard resolution types which air-traffic controllers currently use. This study shows that by utilizing parallel-offset route maneuvers, significant system-wide savings in delay due to conflict resolution of up to 30% are possible. It also shows that most offset resolutions replace horizontal-vectoring resolutions. The second study builds on the results of the first and directly compares offset resolutions and standard horizontal-vectoring maneuvers to determine that in-trail conflicts are often more efficiently resolved by offset maneuvers.

  5. Real-Time, Maneuvering Flight Noise Prediction for Rotorcraft Flight Simulations Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal outlines a plan for developing new technology to provide accurate real-time noise prediction for rotorcraft in steady and maneuvering flight. Main...

  6. Pulsed Electrogasdynamic Thruster for Attitude Control and Orbit Maneuver, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A new pulsed electric thruster, named "pulsed electrogasdynamic thruster," for attitude control and orbit maneuver is proposed. In this thruster, propellant gas is...

  7. Self-Synchronized Fires in Support of Ship-to-Objective Maneuver (STOM)

    National Research Council Canada - National Science Library

    Herman, John

    2002-01-01

    Self-synchronized joint fires in a netted environment are not able to provide the timely and accurate fire support required by infantry units when conducting Ship-to-Objective Maneuver (STOM) operations...

  8. Ion Propulsion System and Orbit Maneuver Integration in CubeSats

    Data.gov (United States)

    National Aeronautics and Space Administration — An integrated cubesat propulsion and control system is proposed that provide three-axis attitude control and orbit maneuver capability using a micro radio-frequency...

  9. Use of Lung Opening Maneuver in Patients with Acute Respiratory Failure After Cardiosurgical Operations

    Directory of Open Access Journals (Sweden)

    A. A. Yeremenko

    2006-01-01

    Full Text Available Postoperative respiratory failure is a most common complication and a main cause of postoperative death. The lung opening maneuver is a most effective method of respiratory therapy for this syndrome.Objective. To evaluate the impact of recruiting maneuver on gas exchange parameters, the biomechanical properties of the lung, and hemodynamic parameters. To determine whether the lung opening maneuver can be fully performed in patients undergoing cardiac surgery.Materials and methods. The study covered 19 patients aged 53 to 70 years who had postoperative failure. The indication for the recruiting maneuver was a decrease in the oxygenation index below 250 mm Hg during assisted ventilation (AV with FiO2>0.5, an inspiratory-expira-tory phase ratio of 1:1 to 3:1, and a positive end-expiratory pressure of 5—10 cm H2O.Results. A decrease in the oxygenation index to 139±36 mm Hg was observed before the recruiting maneuver was applied. Cd;n. averaged 41.1±8.4 ml/cm H2O. After use of the recruiting maneuver, there were increases in the oxygenation index up to 371±121 mm Hg and in Cd;n. up to 64.3±10 ml/cm H2O in all the patients. When the recruiting maneuver was employed, 14 patients were observed to have elevated blood pressures corrected with a vasopressor. One patient developed pneumothorax that was drained in proper time.Conclusion. The application of the lung opening maneuver leads to a considerable improvement of gas exchange parameters and lung mechanical properties.

  10. Cases requiring increased number of repositioning maneuvers in benign paroxysmal positional vertigo

    OpenAIRE

    Korkmaz, Mukadder; Korkmaz, Hakan

    2016-01-01

    ABSTRACT INTRODUCTION: Benign paroxysmal positional vertigo (BPPV) is a clinical syndrome that is proposed to be caused by dislocated utricular debris into semicircular canals. Although the majority of patients are treated by one or two repositioning maneuvers, some of the patients need repeated maneuvers for relief. OBJECTIVE: The goal of this study was to investigate the factors associated with patients with benign paroxysmal positional vertigo who required multiple repositioning proced...

  11. How would surround vehicles move? A Unified Framework for Maneuver Classification and Motion Prediction

    OpenAIRE

    Deo, Nachiket; Rangesh, Akshay; Trivedi, Mohan M.

    2018-01-01

    Reliable prediction of surround vehicle motion is a critical requirement for path planning for autonomous vehicles. In this paper we propose a unified framework for surround vehicle maneuver classification and motion prediction that exploits multiple cues, namely, the estimated motion of vehicles, an understanding of typical motion patterns of freeway traffic and inter-vehicle interaction. We report our results in terms of maneuver classification accuracy and mean and median absolute error of...

  12. Orbit maneuvers with finite thrust. Volume 3: User's guide, part 2

    Science.gov (United States)

    Cornelisse, J. W.

    1984-01-01

    Several software packages were developed and installed on the ESTEC Honeywell L66. These programs called SOMFIT, COMFIT, SOMPLOT, and COMPLOT, respectively, calculate a single transfer maneuver, a set of transfer maneuvers and generate the corresponding plots. In addition to these four programs which use single precision arithmetic, and second version of SOMFIT, called SOMFITD, using double precision arithmetic was installed on the ESTEC Honeywell.

  13. Efficacy of Epley maneuver in treatment of benign paroxysmal positional vertigo of the posterior semicircular canal

    Directory of Open Access Journals (Sweden)

    Babac Snežana

    2012-01-01

    Full Text Available Background/Aim. Benign paroxysmal positional vertigo is one of the most frequent peripheral vestibular system disorders. The aim of this study was to examine the efficacy of the Epley maneuver in treating benign paroxysmal positional vertigo of the posterior semicircular canal (p- BPPV and to discover possible causes of failure. Methods. This prospective study included 75 patients. In all the cases medical history showed and the positioning Dix-Hallpike test confirmed the diagnosis of p-BPPV. We also performed clinical ENT examination, searching for spontaneous nystagmus, vestibulospinal tests, caloric test, and audiometry. All the patients were treated by the modified Epley canalith repositioning maneuver. The patients were followed up at the intervals of seven and, fourteen days, and one, tree, and six months and one year. The maneuver was repeated if vertigo and nystagmus on control positioning test persisted. The transition from positive into negative Dix Hallpike test after one or two Epley maneuver was considered as success in treatment. Results. After the initial Epley maneuver the recovery rate was 90.7%, and after the second 96%. In three (4% patients with secondary p-BPPV, symptoms did not cease even after the second repositioning maneuver. The etiology of p-BPPV had a significant effect on the maneuver’s success rate (p < 0.01, whereas duration of symptoms, age and gender had no effect (p > 0.05. After a successful treatment 11 (14.66% patients had recurrent attack of BPPV during the first year. Conclusion. The Epley maneuver is very successful repositioning procedure in treating p- BPPV. The patients with idiopathic form p-BPPV showed higher success rate with Epley maneuver than those with secondary p-BPPV.

  14. Effect of width and boundary conditions on meeting maneuvers on two-way separated cycle tracks.

    Science.gov (United States)

    Garcia, Alfredo; Gomez, Fernando Agustin; Llorca, Carlos; Angel-Domenech, Antonio

    2015-05-01

    Cycle track design guidelines are rarely based on scientific studies. In the case of off-road two-way cycle tracks, a minimum width must facilitate both passing and meeting maneuvers, being meeting maneuvers the most frequent. This study developed a methodology to observe meeting maneuvers using an instrumented bicycle, equipped with video cameras, a GPS tracker, laser rangefinders and speed sensors. This bicycle collected data on six two-way cycle tracks ranging 1.3-2.15m width delimitated by different boundary conditions. The meeting maneuvers between the instrumented bicycle and every oncoming bicycle were characterized by the meeting clearance between the two bicycles, the speed of opposing bicycle and the reaction of the opposing rider: change in trajectory, stop pedaling or braking. The results showed that meeting clearance increased with the cycle track width and decreased if the cycle track had lateral obstacles, especially if they were higher than the bicycle handlebar. The speed of opposing bicycle shown the same tendency, although were more disperse. Opposing cyclists performed more reaction maneuvers on narrower cycle tracks and on cycle tracks with lateral obstacles to the handlebar height. Conclusions suggested avoiding cycle tracks narrower than 1.6m, as they present lower meeting clearances, lower bicycle speeds and frequent reaction maneuvers. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Epley and Semont maneuvers for posterior canal benign paroxysmal positional vertigo: A network meta-analysis.

    Science.gov (United States)

    Liu, Yun; Wang, Wei; Zhang, Ao-Bo; Bai, Xue; Zhang, Shuang

    2016-04-01

    Using network meta-analysis, we aimed to compare the efficacy and safety of Epley and Semont maneuvers as treatment options for posterior canal benign paroxysmal positional vertigo. Network meta-analysis. Randomized controlled studies with a Jadad score ≥ 3 that used an Epley or Semont maneuver in posterior canal benign paroxysmal positional vertigo patients were analyzed in this project. The following efficacy outcomes included 1-week recovery rate and end of study recovery rate. Recurrence rate was used to assess the safety of each treatment. Of 589 articles, 12 studies that enrolled 999 posterior canal benign paroxysmal positional vertigo patients were selected. The pooled analysis revealed that the Epley maneuver was as efficacious as the Semont maneuver, in both the 1-week recovery rate and end of study recovery rate (odds ratio [OR] = 1.8, 95% confidence interval [CI] = 0.48-7.00; OR = 1.8, 95% CI = 0.47-7.20), and had a similar recurrence rate (OR = 1.00, 95% CI = 0.33-4.4). These two techniques were both better than sham-controlled treatment in the two efficacy indicators. No difference was observed in recurrence rate for treatments. The Epley maneuver was similar to the Semont maneuver in both efficacy and safety for posterior canal benign paroxysmal positional vertigo in short-term effects, and both were superior to the sham-controlled treatment. NA. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  16. Effectiveness of Chin-tuck Maneuver to Facilitate Swallowing in Neurologic Dysphagia

    Directory of Open Access Journals (Sweden)

    Saconato, Mariana

    2015-10-01

    Full Text Available Introduction The chin-tuck maneuver is the most frequently employed postural maneuver in the treatment of neurogenic oropharyngeal dysphagia caused by encephalic vascular strokes and degenerative diseases. Objective The purpose of this study was to investigate the effectiveness of this maneuver in patients with neurogenic dysphagia and factors that could interfere in it. Methods In this retrospective cohort, we analyzed the medical files and videofluoroscopy exams of 35 patients (19 male – 54% and 16 female – 46%; age range between 20 and 89 years old; mean = 69 years. Results The results suggest that the effectiveness of chin-tuck maneuver is related to the overall degree of dysphagia: the more severe the dysphagia, the less effective the maneuver. Conclusion Chin-tuck maneuver should benefit dysphagic patients with delay in the swallowing trigger, reduced laryngeal elevation, and difficulties to swallow liquids, but is not the best compensatory strategy for patients with severe dysphagia.

  17. Epley's Maneuver in Benign Paroxysmal Positional Vertigo: Series of Cases Reports

    Directory of Open Access Journals (Sweden)

    Marchiori, Luciana Lozza de Moraes

    2011-04-01

    Full Text Available Introduction: Benign paroxysmal positional vertigo (BPPV is probably the most common cause of vertigo in women. Objective: To report the result of Epley's maneuver when treating BPPV patients. Method: Study of a series of 9-month-long cases of five female individuals aged between 46 and 64 with BPPV, who were submitted to Epley's maneuver at a scholar clinics, having the positive Dix-Hallpike maneuver at the first consultation as an inclusion criterion, and evaluations were repeated in a six and nine-month term. Results: Only one Epley's maneuver, as the only therapeutic procedure, was enough to eliminate nystagmus and positional vertigo in 4 patients, who did not show a positive Dix-Hallpike maneuver in the two reevaluations performed. Only one patient showed BPPV in the first reevaluation of the study term, and nystagmus reoccurred in the second evaluation only. Conclusion: Epley's repositioning maneuver proved to be a simple and effective BPPV treatment method for this study's patients at length.

  18. A unified flight control methodology for a compound rotorcraft in fundamental and aerobatic maneuvering flight

    Science.gov (United States)

    Thorsen, Adam

    This study investigates a novel approach to flight control for a compound rotorcraft in a variety of maneuvers ranging from fundamental to aerobatic in nature. Fundamental maneuvers are a class of maneuvers with design significance that are useful for testing and tuning flight control systems along with uncovering control law deficiencies. Aerobatic maneuvers are a class of aggressive and complex maneuvers with more operational significance. The process culminating in a unified approach to flight control includes various control allocation studies for redundant controls in trim and maneuvering flight, an efficient methodology to simulate non-piloted maneuvers with varying degrees of complexity, and the setup of an unconventional control inceptor configuration along with the use of a flight simulator to gather pilot feedback in order to improve the unified control architecture. A flight path generation algorithm was developed to calculate control inceptor commands required for a rotorcraft in aerobatic maneuvers. This generalized algorithm was tailored to generate flight paths through optimization methods in order to satisfy target terminal position coordinates or to minimize the total time of a particular maneuver. Six aerobatic maneuvers were developed drawing inspiration from air combat maneuvers of fighter jet aircraft: Pitch-Back Turn (PBT), Combat Ascent Turn (CAT), Combat Descent Turn (CDT), Weaving Pull-up (WPU), Combat Break Turn (CBT), and Zoom and Boom (ZAB). These aerobatic maneuvers were simulated at moderate to high advance ratios while fundamental maneuvers of the compound including level accelerations/decelerations, climbs, descents, and turns were investigated across the entire flight envelope to evaluate controller performance. The unified control system was developed to allow controls to seamlessly transition between manual and automatic allocations while ensuring that the axis of control for a particular inceptor remained constant with flight

  19. Vortex Ring Extremization for Low Speed Maneuvering of Underwater Vehicles

    Science.gov (United States)

    Mohseni, Kamran

    2004-11-01

    Most attempts in underwater locomotion have been focused on propeller thrust generation or recently on flapping locomotion. However, new developments in autonomous and tethered underwater vehicles motivated closer look at the biomimetics of sea animals. To this end, Cephalopoda and jelly fish utilize pulsatile jets and vortex formation for locomotion. To avoid further complications with background flows, we focus on the formation of the leading vortex ring rather than a train of vortices. It is shown that a pinched-off vortex ring characterizes the extremum impulse accumulated by the leading vortex ring in vortex formation process. An appropriate scaling for vortex ring impulse is found and the limiting values of the non-dimensionalized impulses are established. An estimate for the non-dimensional impulses is provided by equating their values from the slug model with their values from a vortex in the Norbury family of vortices. For a vortex ring generator with constant kinetic energy and circulation generation rate, the pinched-off vortex ring has a maximum impulse of I_nd^E ≈ 11 normalized by the circulation and energy. On the other hand, for a vortex ring generator with constant rate of circulation generation at a constant translational velocity, a pinched-off vortex ring produces a minimum impulse of I_nd^Γ ≈ 0.12 normalized by the circulation and translational velocity. Direct numerical simulations of vortex ring formation and vortex ring pinch-off process are performed and the estimated values of the non-dimensionalized impulses are confirmed. These ideas are employed in designing a vortex jet generator for low speed maneuvering of underwater robots. The presented vortex generators are simple and low cost, they consume little valuable payload space, and they have no moving external parts. Experimental data are presented in support of the optimal formation number of 4 for maximum thrust generation.

  20. Intrapartum Pubic Symphysis Disruption

    African Journals Online (AJOL)

    Considering hormonal level normalization after delivery, conservative treatment is the standard for the great majority of cases. Even 4 cm widening tends toward a satisfactory clinical and functional outcome without surgery. However, pregnancy-related severe pubic diastasis must be reduced and fixed to allow pelvic ring ...

  1. Computerized intrapartum fetal monitoring

    International Nuclear Information System (INIS)

    Divon, M.Y.

    1986-01-01

    Preliminary clinical evaluation: Twenty healthy women were studied for 40 minutes each. All were at full-term gestation and had taken no medications during pregnancy or labor. The outcome of each of the pregnancies was entirely normal resulting in appropriately grown, non-asphyxiated infants. Results: (1) uterine contractions occupied 34% of the total observation time (mean duration = 67 +- 15 seconds (+- SD)), (2) all fetuses demonstrated FM (mean frequency = 2.5 per 10 minutes; mean duration = 11 seconds). FM were significantly more common during UC., 3) 85% of FHR accelerations were associated with FM as detected by real-time sonography, (4) FHRV rose from 5.1 +- 1.3 (mean +- SD) between UC to 6.0 +- 1.5 during UC, rho < 0.001. This system provides the clinician with clear, objective and concise information which may be useful in early recognition of the compromised fetus

  2. Care during labor and birth for the prevention of intrapartum-related neonatal deaths: a systematic review and Delphi estimation of mortality effect

    Directory of Open Access Journals (Sweden)

    Moran Neil F

    2011-04-01

    Full Text Available Abstract Background Our objective was to estimate the effect of various childbirth care packages on neonatal mortality due to intrapartum-related events (“birth asphyxia” in term babies for use in the Lives Saved Tool (LiST. Methods We conducted a systematic literature review to identify studies or reviews of childbirth care packages as defined by United Nations norms (basic and comprehensive emergency obstetric care, skilled care at birth. We also reviewed Traditional Birth Attendant (TBA training. Data were abstracted into standard tables and quality assessed by adapted GRADE criteria. For interventions with low quality evidence, but strong GRADE recommendation for implementation, an expert Delphi consensus process was conducted to estimate cause-specific mortality effects. Results We identified evidence for the effect on perinatal/neonatal mortality of emergency obstetric care packages: 9 studies (8 observational, 1 quasi-experimental, and for skilled childbirth care: 10 studies (8 observational, 2 quasi-experimental. Studies were of low quality, but the GRADE recommendation for implementation is strong. Our Delphi process included 21 experts representing all WHO regions and achieved consensus on the reduction of intrapartum-related neonatal deaths by comprehensive emergency obstetric care (85%, basic emergency obstetric care (40%, and skilled birth care (25%. For TBA training we identified 2 meta-analyses and 9 studies reporting mortality effects (3 cRCT, 1 quasi-experimental, 5 observational. There was substantial between-study heterogeneity and the overall quality of evidence was low. Because the GRADE recommendation for TBA training is conditional on the context and region, the effect was not estimated through a Delphi or included in the LiST tool. Conclusion Evidence quality is rated low, partly because of challenges in undertaking RCTs for obstetric interventions, which are considered standard of care. Additional challenges for

  3. Care during labor and birth for the prevention of intrapartum-related neonatal deaths: a systematic review and Delphi estimation of mortality effect

    Science.gov (United States)

    2011-01-01

    Background Our objective was to estimate the effect of various childbirth care packages on neonatal mortality due to intrapartum-related events (“birth asphyxia”) in term babies for use in the Lives Saved Tool (LiST). Methods We conducted a systematic literature review to identify studies or reviews of childbirth care packages as defined by United Nations norms (basic and comprehensive emergency obstetric care, skilled care at birth). We also reviewed Traditional Birth Attendant (TBA) training. Data were abstracted into standard tables and quality assessed by adapted GRADE criteria. For interventions with low quality evidence, but strong GRADE recommendation for implementation, an expert Delphi consensus process was conducted to estimate cause-specific mortality effects. Results We identified evidence for the effect on perinatal/neonatal mortality of emergency obstetric care packages: 9 studies (8 observational, 1 quasi-experimental), and for skilled childbirth care: 10 studies (8 observational, 2 quasi-experimental). Studies were of low quality, but the GRADE recommendation for implementation is strong. Our Delphi process included 21 experts representing all WHO regions and achieved consensus on the reduction of intrapartum-related neonatal deaths by comprehensive emergency obstetric care (85%), basic emergency obstetric care (40%), and skilled birth care (25%). For TBA training we identified 2 meta-analyses and 9 studies reporting mortality effects (3 cRCT, 1 quasi-experimental, 5 observational). There was substantial between-study heterogeneity and the overall quality of evidence was low. Because the GRADE recommendation for TBA training is conditional on the context and region, the effect was not estimated through a Delphi or included in the LiST tool. Conclusion Evidence quality is rated low, partly because of challenges in undertaking RCTs for obstetric interventions, which are considered standard of care. Additional challenges for evidence interpretation

  4. Qualitative analysis of the Dix-Hallpike maneuver in multi-canal BPPV using a biomechanical model: Introduction of an expanded Dix-Hallpike maneuver for enhanced diagnosis of multi-canal BPPV

    Directory of Open Access Journals (Sweden)

    Henri Traboulsi

    2017-09-01

    Conclusion: The Dix–Hallpike maneuver may cause simultaneous movement of otoliths present in multiple canals and create an obstacle to accurate diagnosis in multi-canal BPPV. An expanded Dix-Hallpike maneuver is described which adds intermediate steps with the head positioned to the right and left in the horizontal position before head-hanging. This expanded maneuver has helped to isolate affected semi-circular canals for individual assessment in multiple canal BPPV.

  5. Comparison of Mallampati test with lower jaw protrusion maneuver in predicting difficult laryngoscopy and intubation

    Science.gov (United States)

    Ul Haq, Muhammad Irfan; Ullah, Hameed

    2013-01-01

    Background: Failure to maintain a patent airway is one of the commonest causes of anesthesia-related morbidity and mortality. Many protocols, algorithms, and different combinations of tested methods for airway assessment have been developed to predict difficult laryngoscopy and intubation. The reported incidence of a difficult intubation varies from 1.5% to 13%. The objective of this study was to compare Mallampati test (MT) with lower jaw protrusion (LJP) maneuver in predicting difficult laryngoscopy and intubation. Materials and Methods: Seven hundred and sixty patients were included in the study. All the patients underwent MT and LJP maneuver for their airway assessment. After a standardized technique of induction of anesthesia, primary anesthetist performed laryngoscopy and graded it according to the grades described by Cormack and Lehane. Sensitivity, specificity, accuracy, and positive predictive value (PPV) and negative predictive value (NPV) were calculated for both these tests with 95% confidence interval (CI) using conventional laryngoscopy as gold standard. Area under curve was also calculated for both, MT and LJP maneuver. A P < 0.05 was taken as significant. Results: LJP maneuver had higher sensitivity (95.9% vs. 27.1%), NPV (98.7% vs. 82.0%), and accuracy (90.1% vs. 80.3%) when compared to MT in predicting difficult laryngoscopy and intubation. Both tests, however, had similar specificity and PPV. There was marked difference in the positive and negative likelihood ratio between LJP and MT. Similarly, the area under the curve favored LJP maneuver over MT. Conclusion: The results of this study show that LJP maneuver is a better test to predict difficult laryngoscopy and tracheal intubation. We recommend the addition of this maneuver to the routine preoperative evaluation of airway. PMID:24106353

  6. Comparison of Mallampati test with lower jaw protrusion maneuver in predicting difficult laryngoscopy and intubation

    Directory of Open Access Journals (Sweden)

    Muhammad Irfan Ul Haq

    2013-01-01

    Full Text Available Background: Failure to maintain a patent airway is one of the commonest causes of anesthesia-related morbidity and mortality. Many protocols, algorithms, and different combinations of tested methods for airway assessment have been developed to predict difficult laryngoscopy and intubation. The reported incidence of a difficult intubation varies from 1.5% to 13%. The objective of this study was to compare Mallampati test (MT with lower jaw protrusion (LJP maneuver in predicting difficult laryngoscopy and intubation. Materials and Methods: Seven hundred and sixty patients were included in the study. All the patients underwent MT and LJP maneuver for their airway assessment. After a standardized technique of induction of anesthesia, primary anesthetist performed laryngoscopy and graded it according to the grades described by Cormack and Lehane. Sensitivity, specificity, accuracy, and positive predictive value (PPV and negative predictive value (NPV were calculated for both these tests with 95% confidence interval (CI using conventional laryngoscopy as gold standard. Area under curve was also calculated for both, MT and LJP maneuver. A P < 0.05 was taken as significant. Results: LJP maneuver had higher sensitivity (95.9% vs. 27.1%, NPV (98.7% vs. 82.0%, and accuracy (90.1% vs. 80.3% when compared to MT in predicting difficult laryngoscopy and intubation. Both tests, however, had similar specificity and PPV. There was marked difference in the positive and negative likelihood ratio between LJP and MT. Similarly, the area under the curve favored LJP maneuver over MT. Conclusion: The results of this study show that LJP maneuver is a better test to predict difficult laryngoscopy and tracheal intubation. We recommend the addition of this maneuver to the routine preoperative evaluation of airway.

  7. Rapid systematic review of repeated application of the epley maneuver for treating posterior BPPV.

    Science.gov (United States)

    Reinink, Hendrik; Wegner, Inge; Stegeman, Inge; Grolman, Wilko

    2014-09-01

    To evaluate the effect of repeated application of the Epley maneuver on patient-reported symptom relief and resolution of nystagmus in patients with posterior benign paroxysmal positional vertigo (p-BPPV). PubMed, Embase, and the Cochrane Library. A systematic search was conducted. Studies reporting original study data were included. Relevance and risk of bias (RoB) of the selected articles were assessed. Studies with low relevance, high RoB, or both were excluded. Success percentages and mean values were extracted. A total of 955 unique studies were retrieved. Fourteen of these satisfied the eligibility criteria. All of the included studies carried a high relevance and a moderate RoB. The majority of studies were 1-armed trials, in which the Epley was repeated only in case previous attempt(s) had failed. The maneuver was not repeated if it was successful. In 32% to 90% of patients, the first treatment session was successful. Reported cumulative success percentages ranged from 40% to 100% after the second session, 67% to 98% after the third session, 87% to 100% after the fourth session, and 100% in the studies in which patients received 5 sessions. One study evaluating the effect of multiple maneuvers in a single session showed a rise in success percentages from 84% for 1 maneuver to 90% after 2 maneuvers and 92% after 3 maneuvers. Multiple studies with moderate RoB show a beneficial effect of multiple sessions of the Epley maneuver in p-BPPV patients who are not fully cleared of symptoms after the first session. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014.

  8. Mechanical Constraints on Flight at High Elevation Decrease Maneuvering Performance of Hummingbirds.

    Science.gov (United States)

    Segre, Paolo S; Dakin, Roslyn; Read, Tyson J G; Straw, Andrew D; Altshuler, Douglas L

    2016-12-19

    High-elevation habitats offer ecological advantages including reduced competition, predation, and parasitism [1]. However, flying organisms at high elevation also face physiological challenges due to lower air density and oxygen availability [2]. These constraints are expected to affect the flight maneuvers that are required to compete with rivals, capture prey, and evade threats [3-5]. To test how individual maneuvering performance is affected by elevation, we measured the free-flight maneuvers of male Anna's hummingbirds in a large chamber translocated to a high-elevation site and then measured their performance at low elevation. We used a multi-camera tracking system to identify thousands of maneuvers based on body position and orientation [6]. At high elevation, the birds' translational velocities, accelerations, and rotational velocities were reduced, and they used less demanding turns. To determine how mechanical and metabolic constraints independently affect performance, we performed a second experiment to evaluate flight maneuvers in an airtight chamber infused with either normoxic heliox, to lower air density, or nitrogen, to lower oxygen availability. The hypodense treatment caused the birds to reduce their accelerations and rotational velocities, whereas the hypoxic treatment had no significant effect on maneuvering performance. Collectively, these experiments reveal how aerial maneuvering performance changes with elevation, demonstrating that as birds move up in elevation, air density constrains their maneuverability prior to any influence of oxygen availability. Our results support the hypothesis that changes in competitive ability at high elevations are the result of mechanical limits to flight performance [7]. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Massive facial teratoma managed with the ex utero intrapartum treatment (EXIT procedure and use of a 3-dimensional printed model for planning of staged debulking

    Directory of Open Access Journals (Sweden)

    Maggie M. Hodges

    2017-02-01

    Full Text Available Teratomas are the most frequent solid tumor found in neonates. However, only 1.5% of neonatal teratomas originate from facial structures. Neonatal facial teratomas are associated with polyhydramnios, preterm birth, pulmonary hypoplasia, cleft palate, cleft lip, and life-threatening airway compromise. The overall survival reported with these lesions has been between 17 and 87.5%; however survival in the setting of antenatally diagnosed facial teratomas has only been described anecdotally. We present a case of an antenatally diagnosed massive facial teratoma originating from the pterygomaxillary fossa, which was associated with polyhydramnios and pre-term birth. We managed this complex tumor with an ex utero intrapartum treatment (EXIT procedure, multidisciplinary medical and surgical team, and staged excision and reconstruction aided by use of a 3-dimensional printed model. Here we review the surgical management of this rare and complex tumor.

  10. Correlação entre a pressão de perda à manobra de Valsalva e a pressão máxima de fechamento uretral com a história clínica em mulheres com incontinência urinária de esforço Correlation of Valsalva leak point pressure and maximal urethral closure pressure with clinical history in women with stress urinary incontinence

    Directory of Open Access Journals (Sweden)

    Paulo Cezar Feldner Jr

    2002-08-01

    Full Text Available Objetivo: analisar a relação entre a pressão de perda com manobra de Valsalva e a pressão máxima de fechamento uretral com a queixa clínica em mulheres com incontinência urinária de esforço. Métodos: estudo retrospectivo no qual foram incluídas 164 pacientes com diagnóstico de incontinência urinária de esforço ou mista atendidas no setor de Uroginecologia e Cirurgia Vaginal do Departamento de Ginecologia da UNIFESP/EPM. As pacientes submeteram-se à anamnese padronizada, exame físico e estudo urodinâmico. A pressão de perda foi mensurada sob manobra de Valsalva (Valsalva leak point pressure - VLPP, com volume vesical de 200 mL. O perfil uretral foi realizado utilizando-se cateter de fluxo número 8, sendo medida a pressão máxima de fechamento uretral (PMFU. As pacientes foram agrupadas conforme a queixa clínica de perda urinária aos esforços e realizou-se análise estatística por meio do teste de chi² para verificar a proporção entre as variáveis. Utilizou-se, a seguir, a análise de variância (ANOVA para verificar diferenças entre VLPP e PMFU com relação à gravidade subjetiva da incontinência. Resultados: a média de idade foi de 51,2 anos (19-82, sendo que 79 encontravam-se no menacme (48,2% e 85 (51,8% na pós-menopausa. A paridade média foi de 4,0 filhos (0-18. Houve correlação entre o número de pacientes com VLPP inferior a 60 cmH2O e a queixa clínica (pPurpose: to analyze the correlation between Valsalva leak point pressure and maximum urethral closure pressure and clinical symptoms in women with stress urinary incontinence. Methods: we analyzed retrospectively 164 patients with urodynamic diagnosis of stress and mixed urinary incontinence established by the Urogynecology and Vaginal Surgery Sector of UNIFESP/EPM. All patients were submmited to medical interview, physical examination and urodynamic study. Patients were divided into groups according to the subjective degree of stress urinary

  11. Ship operation and failure mode analysis using a maneuver simulator

    Science.gov (United States)

    Cabrerizo-Morales, Miguel Angel; Molina, Rafael; de los Santos, Francisco; Camarero, Alberto

    2013-04-01

    In a ship or floating structure operation the agents that contribute to the systems behaviour are not only those derived from fluid-structure interaction, but also the ones linked to mooring-control line set-up evolution and human interaction. Therefore, the analysis of such systems is affected by boundary conditions that change during a complete operation. Frequently, monitoring techniques in laboratory (model) and field (prototype) are based in different instrumental techniques adding difficulty to data comparison and, in some cases, inducing precision and repeatability errors. For this reason, the main aim of this study is to develop the methods and tools to achieve a deep knowledge of those floating systems and obtain capabilities to optimize their operationally thresholds. This abstract presents a methodology and an instrumental system applicable both in field and laboratory: SRECMOCOS Project (Small scale REal-time Caisson MOnitoring and COntrol System). SRECMOCOS compiles three modules. For the monitoring and control of the structure it has been developed a synchronized open and modular microcontroller-based electronic system that comprises sensors, to monitor agents and reactions, and actuators to perform pertinent actions after processing the sensors' data. A secondary objective has been to design and implement a global scaled simulator (1:22), at the 3D basin of The Harbour Research Lab at Technical University of Madrid, in which climatic agents and those derived from the rig/maneuvering setup and the structural design were included. The particular case of Campamento's drydock, in Algeciras Bay (Spain), has been used to apply and validate the methodology. SRECMOCOS Project conjugates control, monitoring and wireless communication systems in a real time basis, offering the possibility to register and simulate all the parameters involved in port operations. This approach offers a step forward into a monitoring strategy to be included in monitoring

  12. A qualitative study exploring how Somali women exposed to female genital mutilation experience and perceive antenatal and intrapartum care in England.

    Science.gov (United States)

    Moxey, Jordan M; Jones, Laura L

    2016-01-07

    To explore how Somali women exposed to female genital mutilation experience and perceive antenatal and intrapartum care in England. We explored women's perceptions of deinfibulation, caesarean section and vaginal delivery; their experiences of care during pregnancy and labour; and factors that affect ability to access these services, in order to make recommendations about future practice. A descriptive, exploratory qualitative study using face-to-face semistructured interviews. Interviews were audio-recorded, transcribed and data were analysed using a thematic approach. An interpreter was used when required (n=3). Participants recruited from 2 community centres in Birmingham, England. Convenience and snowball sample of 10 Somali women resident in Birmingham, who had accessed antenatal care services in England within the past 5 years. 3 core themes were interpreted: (1) Experiences of female genital mutilation during life, pregnancy and labour: Female genital mutilation had a significant physical and psychological impact, influencing decisions to undergo deinfibulation or caesarean section. Women delayed deinfibulation until labour to avoid undergoing multiple operations if an episiotomy was anticipated. (2) Experience of care from midwives: Awareness of female genital mutilation from midwives led to open communication and stronger relationships with women, resulting in more positive experiences. (3) Adaptation to English life: Good language skills and social support networks enabled women to access these services, while unfavourable social factors (eg, inability to drive) impeded. Female genital mutilation impacts Somali women's experiences of antenatal and intrapartum care. This study suggests that midwives should routinely ask Somali women about female genital mutilation to encourage open communication and facilitate more positive experiences. As antenatal deinfibulation is unpopular, we should consider developing strategies to promote deinfibulation to non

  13. The association between a low cerebro-umbilical ratio at 30-34 weeks gestation, increased intrapartum operative intervention and adverse perinatal outcomes.

    Science.gov (United States)

    Twomey, Sarah; Flatley, Christopher; Kumar, Sailesh

    2016-08-01

    The aim of this study was to investigate the relationship between the cerebro-umbilical ratio (CUR), measured at 30-34 weeks, and adverse intrapartum and perinatal outcomes. This was a retrospective cross-sectional cohort study of women delivering at the Mater Mothers' Hospital in Brisbane, Australia. Fetal Doppler indices for 1224 singleton pregnancies were correlated with maternal demographics and intrapartum and perinatal outcomes. Only women who attempted vaginal delivery were included in the study. Infants delivered by emergency cesarean section for fetal compromise had the lowest median CUR, 1.65 (IQR 1.17-2.12), compared to any other delivery group. The proportion of infants with a CUR ≤1 who required emergency cesarean section for fetal compromise was 33.3% compared to 9.3% of infants with a CUR >1 (adjusted OR 6.92 (95% CI 2.04-25.75), p<0.001). However, the detection rate of CUR ≤1 as a predictor for emergency cesarean delivery for fetal compromise was poor (18.9%). Detection rates increased in cohorts of infants born within two weeks of the scan or with birth weights <10th centile or <5th centile. Additionally, a CUR ≤1 was associated with lower median birth weight, higher rates of admission to the neonatal critical care unit and increased neonatal mortality. This study suggests that a CUR ≤1, measured at 30-34 weeks, is associated with a greater risk of emergency cesarean delivery for fetal compromise and a number of other adverse perinatal outcomes. The association was strongest in low birth weight babies. Copyright © 2016. Published by Elsevier Ireland Ltd.

  14. An Analytical Solution for Yaw Maneuver Optimization on the International Space Station and Other Orbiting Space Vehicles

    Science.gov (United States)

    Dobrinskaya, Tatiana

    2015-01-01

    This paper presents a new method for optimizing yaw maneuvers, which are the most common large maneuvers on the International Space Station (ISS). The goal of the maneuver optimization is to find a maneuver trajectory with minimal torques acting on the vehicle during the maneuver. Therefore, the thruster firings necessary to perform the maneuver are minimized. Reduction of thruster firings saves propellant and decreases structural loads and contamination of the vehicle critical elements, thus saving the service life of the thrusters and the vehicle itself. Equations describing the pitch and roll motion needed to counteract the major torques during a yaw maneuver are obtained. Also, a yaw rate profile is suggested. In the obtained optimized case, the torques are significantly reduced. The proposed approximate analytical solution does not require extensive computer resources and, therefore, can be implemented using software onboard the ISS. As a result, the maneuver execution will be automatic. This is one of the major benefits of the simplified solution presented in this paper with respect to existing computational approaches. The suggested maneuver optimization method can be used not only for the ISS, but for other space vehicles as well.

  15. The influence of airway supporting maneuvers on glottis view in pediatric fiberoptic bronchoscopy

    Directory of Open Access Journals (Sweden)

    Tarik Umutoglu

    2015-10-01

    Full Text Available ABSTRACTINTRODUCTION:Flexible fiber optic bronchoscopy is a valuable intervention for evaluation and management of respiratory diseases in both infants, pediatric and adult patients. The aim of this study is to investigate the influence of the airway supporting maneuvers on glottis view during pediatric flexible fiberoptic bronchoscopy.MATERIALS AND METHODS:In this randomized, controlled, crossover study; patients aged between 0 and 15 years who underwent flexible fiberoptic bronchoscopy procedure having American Society of Anesthesiologists I---II risk score were included. Patients having risk of difficult intubation, intubated or patients with tracheostomy, and patients with reduced neck mobility or having cautions for neck mobility were excluded from this study. After obtaining best glottic view at the neutral position, patients were positioned jaw trust with open mouth, jaw trust with teeth prottution, head tilt chin lift and triple airway maneuvers and best glottis scores were recorded.RESULTS:Total of 121 pediatric patients, 57 girls and 64 boys, were included in this study. Both jaw trust with open mouth and jaw trust with teeth prottution maneuvers improved the glottis view compared with neutral position (p 0.05. Head tilt chin lift and triple airway maneuvers improved glottis view when compared with both jaw trust with open mouth and jaw trust with teeth prottution maneuvers and neutral position (p 0.05.

  16. Effects of hamstring stretching on passive muscle stiffness vary between hip flexion and knee extension maneuvers.

    Science.gov (United States)

    Miyamoto, N; Hirata, K; Kanehisa, H

    2017-01-01

    The purpose of this study was to examine whether the effects of hamstring stretching on the passive stiffness of each of the long head of the biceps femoris (BFl), semitendinosus (ST), and semimembranosus (SM) vary between passive knee extension and hip flexion stretching maneuvers. In 12 male subjects, before and after five sets of 90 s static stretching, passive lengthening measurements where knee or hip joint was passively rotated to the maximal range of motion (ROM) were performed. During the passive lengthening, shear modulus of each muscle was measured by ultrasound shear wave elastography. Both stretching maneuvers significantly increased maximal ROM and decreased passive torque at a given joint angle. Passive knee extension stretching maneuver significantly reduced shear modulus at a given knee joint angle in all of BFl, ST, and SM. In contrast, the stretching effect by passive hip flexion maneuver was significant only in ST and SM. The present findings indicate that the effects of hamstring stretching on individual passive muscles' stiffness vary between passive knee extension and hip flexion stretching maneuvers. In terms of reducing the muscle stiffness of BFl, stretching of the hamstring should be performed by passive knee extension rather than hip flexion. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. THE EFFECTIVENESS OF SEMONT LIBERATORY MANEUVER IN ACUTE BENINGN PAROXYSMAL POSITIONAL VERTIGO PATIENTS

    Directory of Open Access Journals (Sweden)

    Achyutha Kiran Kumar

    2014-08-01

    Full Text Available Background: People with vestibular dysfunction complain of problems with balance and dizziness which creates a negative impact on the people and affects their quality of life. Medications help in the control of symptoms. There has been an increase in the implementation of many protocols for the rehabilitation of vestibular patients with follow up exercises for the treatment of BPPV. Methods: Thirty BPPV patients were identified by doing Dix- Hall pike positioning and their DHI scores were recorded. All patients were exclusively treated with Semont Liberatory maneuver. The effectiveness of the treatment was documented at 1 week and 1 month. Repeated procedures were performed if necessary. Results: After the treatment session of Semont Liberatory maneuver, the symptoms disappeared in 20 patients and have negative DHI test by 1st week, and of patients have negative DHI test by 1 month. The first success rate was 78% and the total success rate was 89%. Semont Liberatory maneuver also showed decrease in score of DHI [post-test] in 1 month duration. The patient who visited within one week after the onset of symptoms had good prognosis with Semont Liberatory maneuver. This protocol was ineffective in 4 patients. Conclusion: The Semont Liberatory maneuver is a safe and effective technique for treating BPPV patients.

  18. Variables Affecting Canalith Repositioning Maneuver (CRM Trend for Treating Patients with Benign Paroxysmal Positional Vertigo (BPPV

    Directory of Open Access Journals (Sweden)

    E. Entezari

    2006-07-01

    Full Text Available Background: The purpose of this study was to identify variables affecting outcome in patients with benign paroxysmal positional vertigo (BPPV treated with canalith repositioning maneuver (CRM. Methods: This interventional study was conducted on 58 patients (14 males, 44 females, mean age 48.12+13.22 referred to the Vertigo Rehabilitation Clinic of the Rehabilitation School of Tehran University of Medical Sciences from 2002 to 2004. All patients were treated with CRM. According to the treatment efficacy the patients were allocated in three groups: completely treated, partially treated, and not treated. The effect of factors including age, sex, etiology, duration of BPPV, unilateral or bilateral disease, number of maneuvers, and number of sessions on outcome in patients was evaluated. Results: Forty-nine patients (84.5% were completely cured. Age, sex, etiology, and duration did not significantly affect the treatment outcome. Unilateral BPPV can be treated significantly better than bilateral BPPV. Forty-seven patients who were completely treated needed 1 session and thirty-seven of them required 2 maneuvers. Conclusion: CRM is significantly effective for BPPV treatment. Treating unilateral BPPV is expected to be easier. As most of the patients will be cured by 1 or 2 maneuvers or in 1 session, patients who required more sessions or more maneuvers may not be completely treated.

  19. Is it important to repeat the positioning maneuver after the treatment for benign paroxysmal positional vertigo?

    Directory of Open Access Journals (Sweden)

    Alexandra Kolontai de Sousa Oliveira

    2015-04-01

    Full Text Available INTRODUCTION: Benign paroxysmal positional vertigo (BPPV is the most common cause of peripheral vestibular dysfunction.OBJECTIVE: To assess whether the performance of the Dix-Hallpike maneuver after the Epley positioning maneuver has prognostic value in the evolution of unilateral ductolithiasis of posterior semicircular canal.METHODS: A prospective cohort study in monitored patients at otoneurology ambulatory with a diagnosis of BPPV; they were submitted to the therapeutic maneuver and then to a retest in order to evaluate the treatment effectiveness; all cases were reassessed one week later and the retest prognostic value was evaluated.RESULTS: A sample of 64 patients which 47 belonging to negative retest group and 17 belonging to positive retest. Performed the maneuver in all patients, the retest presented 51.85% sensitivity, 91.89% specificity, 82.35% positive predictive value and 72.34% negative predictive value.CONCLUSION: The study shows that doing the retest after repositioning maneuver of particles in BPPV is effectual, since it has high specificity.

  20. Efficacy of the Li maneuver in treating posterior canal benign paroxysmal positional vertigo.

    Science.gov (United States)

    Li, Jinrang; Tian, Shiyu; Zou, Shizhen

    2017-06-01

    The Li maneuver is a safe, effective, and simple repositioning method for the treatment of BPPV. It is simple to master and exerts an exact effect. As a rapid repositioning method, the Li maneuver can result in reduced treatment times and increased treatment efficacy, and is, therefore, especially suitable for patients with limited cervical spine movement. To compare the short-term efficacies of the Li and Epley maneuvers in treating posterior canal benign paroxysmal positional vertigo (PC-BPPV). A total of 120 patients with PC-BPPV were randomly treated by either the Li or Epley maneuvers at our department between May 5, 2014 and July 30, 2015. Follow-up examinations were performed 3 days and 1 week after the first repositioning. Of the 120 patients initially enrolled, 113 (72 females; 41 males; average age = 52 years; Li and Epley maneuver groups, 56 and 57 cases, respectively) satisfied the inclusion and exclusion criteria of this study. There were no statistically significant differences between the two groups of patients in terms of the success rates of treatment at either the 3-day or 1-week follow-ups (p = .756 and .520, respectively).

  1. Multiple Maneuvering Target Tracking by Improved Particle Filter Based on Multiscan JPDA

    Directory of Open Access Journals (Sweden)

    Jing Liu

    2012-01-01

    Full Text Available The multiple maneuvering target tracking algorithm based on a particle filter is addressed. The equivalent-noise approach is adopted, which uses a simple dynamic model consisting of target state and equivalent noise which accounts for the combined effects of the process noise and maneuvers. The equivalent-noise approach converts the problem of maneuvering target tracking to that of state estimation in the presence of nonstationary process noise with unknown statistics. A novel method for identifying the nonstationary process noise is proposed in the particle filter framework. Furthermore, a particle filter based multiscan Joint Probability Data Association (JPDA filter is proposed to deal with the data association problem in a multiple maneuvering target tracking. In the proposed multiscan JPDA algorithm, the distributions of interest are the marginal filtering distributions for each of the targets, and these distributions are approximated with particles. The multiscan JPDA algorithm examines the joint association events in a multiscan sliding window and calculates the marginal posterior probability based on the multiscan joint association events. The proposed algorithm is illustrated via an example involving the tracking of two highly maneuvering, at times closely spaced and crossed, targets, based on resolved measurements.

  2. Evaluation of healthcare professionals' understanding of eponymous maneuvers and mnemonics in emergency obstetric care provision.

    Science.gov (United States)

    Jan, Haider; Guimicheva, Boriana; Gosh, Srirupa; Hamid, Rosol; Penna, Leonie; Sarris, Ippokratis

    2014-06-01

    To evaluate whether eponymous maneuvers and mnemonics taught for the management of shoulder dystocia, vaginal breech delivery, and uterine inversion were remembered and understood in practice. A questionnaire was distributed to obstetricians and midwives collecting information about the HELPERR and PALE SISTER mnemonics. Three extended matching questions evaluated participants' knowledge of the correct maneuvers, with their matching eponyms, used in the management of shoulder dystocia, vaginal breech delivery, and uterine inversion. Of the 112 participants, 90% were familiar with the HELPERR mnemonic, with 79% using it in their practice. Of those who used it, only 32% could correctly decipher it (P = 0.032). PALE SISTER was mostly unfamiliar. The percentages of correct maneuvers used for managing shoulder dystocia, breech delivery, and uterine inversion were 84.6%, 58.3%, and 28.6%, respectively. However, the eponyms were correctly matched to their maneuvers in only 33.3%, 14.3%, and 0% of cases, respectively (P mnemonics for obstetric emergencies were frequently recalled incorrectly. This, together with the poor correlation between knowledge of maneuvers and their eponyms, limits their usefulness and indicates that teaching should focus on learning without relying on mnemonics and eponyms. Copyright © 2014 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  3. Vzájemný vztah maximálního uzávěrového tlaku uretry a Valsalva Leak-Point Pressure u žen se stresovým typem inkontince moči

    Czech Academy of Sciences Publication Activity Database

    Martan, A.; Mašata, J.; Švabík, K.; Drahorádová, P.; Halaška, M.; Voigt, R.; Pavlíková, Markéta

    2004-01-01

    Roč. 69, č. 4 (2004), s. 267-272 ISSN 1210-7832 R&D Projects: GA MZd NH7378 Keywords : inkontinence moči u žen * maximální uzávěrový tlak uretry * Valsalva leak-point pressure Subject RIV: FK - Gynaecology, Childbirth

  4. Vzájemný vztah mezi mobilitou a maximálním uzávěrovým tlakem uretry či Valsalva Leak-Point Pressure u žen se stresovým typem inkontince moči

    Czech Academy of Sciences Publication Activity Database

    Martan, A.; Mašata, J.; Švabík, K.; Drahorádová, P.; Hlásenská, Jana; Pavlíková, Markéta

    2005-01-01

    Roč. 70, č. 4 (2005), s. 123-128 ISSN 1210-7832 R&D Projects: GA MZd NH7378 Keywords : inkontinence moči u žen * hypermobilita uretry * maximální uzávěrový tlak uretry * Valsalva leak-point pressure Subject RIV: FK - Gynaecology, Childbirth

  5. Control of the axial offset in a nuclear reactor at power maneuvering

    Directory of Open Access Journals (Sweden)

    Maksim V. Maksimov

    2014-12-01

    Full Text Available High reliability and security of power unit are basic requirements when the power unit maneuvering mode operation. The reactor stability under disturbances both at steady load and maneuvering load embodies the guarantees of power unit safe and reliable operation. A quantitative measure of the reactor stability is assessed by the axial offset representing the technological characteristics of energy release uniformity, therefore the axial offset minimum deviation is WWER-1000 operation efficiency measure. The power unit capacity automated control systems’ influence on axial offset under maneuvering mode is investigated. Considered is the power unit compromise-combined control program, which maintains a constant axial offset value when power unit switching from one power level to another.

  6. Effect of Conflict Resolution Maneuver Execution Delay on Losses of Separation

    Science.gov (United States)

    Cone, Andrew C.

    2010-01-01

    This paper examines uncertainty in the maneuver execution delay for data linked conflict resolution maneuvers. This uncertainty could cause the previously cleared primary conflict to reoccur or a secondary conflict to appear. Results show that the likelihood of a primary conflict reoccurring during a horizontal conflict resolution maneuver increases with larger initial turn-out angles and with shorter times until loss of separation. There is also a significant increase in the probability of a primary conflict reoccurring when the time until loss falls under three minutes. Increasing horizontal separation by an additional 1.5 nmi lowers the risk, but does not completely eliminate it. Secondary conflicts were shown to have a small probability of occurring in all tested configurations.

  7. Tracking Maneuvering Group Target with Extension Predicted and Best Model Augmentation Method Adapted

    Directory of Open Access Journals (Sweden)

    Linhai Gan

    2017-01-01

    Full Text Available The random matrix (RM method is widely applied for group target tracking. The assumption that the group extension keeps invariant in conventional RM method is not yet valid, as the orientation of the group varies rapidly while it is maneuvering; thus, a new approach with group extension predicted is derived here. To match the group maneuvering, a best model augmentation (BMA method is introduced. The existing BMA method uses a fixed basic model set, which may lead to a poor performance when it could not ensure basic coverage of true motion modes. Here, a maneuvering group target tracking algorithm is proposed, where the group extension prediction and the BMA adaption are exploited. The performance of the proposed algorithm will be illustrated by simulation.

  8. Therapeutic effect of Epley maneuver on patients with posterior semicircular canal in benign paroxysmal positional vertigo

    Directory of Open Access Journals (Sweden)

    Gholamali Dashti-Khadivaki

    2010-06-01

    Full Text Available Background: Benign paroxysmal positional vertigo (BPPV is characterized by brief attacks of vertigo, nausea and/or positional nystagmus during head movements. Epley maneuver is one of the therapeutic processes for these patients and had various results in different studies. The objective of this study was to determine the efficacy of this procedure on treatment of patients with BPPV.Material and Methods: This study was performed from January 2008 till September 2009 in otolaryngology clinic of Khatam teaching hospital in Zahedan. The study was conducted among 67 patients (38 female, 29 male with p-BPPV between the ages of 27 and 68 years old. Epley maneuver with restriction was performed for treatment after diagnosis of BPPV and one week later, results evaluated using the Dix-Hallpike test.Result: 92.5% of patients had positive response to this type of treatment. Conclusions: The study revealed good efficacy of Epley maneuver on patients with BPPV

  9. Analysis of effects of manhole covers on motorcycle driver maneuvers: a nonparametric classification tree approach.

    Science.gov (United States)

    Chang, Li-Yen

    2014-01-01

    A manhole cover is a removable plate forming the lid over the opening of a manhole to allow traffic to pass over the manhole and to prevent people from falling in. Because most manhole covers are placed in roadway traffic lanes, if these manhole covers are not appropriately installed or maintained, they can represent unexpected hazards on the road, especially for motorcycle drivers. The objective of this study is to identify the effects of manhole cover characteristics as well as driver factors and traffic and roadway conditions on motorcycle driver maneuvers. A video camera was used to record motorcycle drivers' maneuvers when they encountered an inappropriately installed or maintained manhole cover. Information on 3059 drivers' maneuver decisions was recorded. Classification and regression tree (CART) models were applied to explore factors that can significantly affect motorcycle driver maneuvers when passing a manhole cover. Nearly 50 percent of the motorcycle drivers decelerated or changed their driving path to reduce the effects of the manhole cover. The manhole cover characteristics including the level difference between manhole cover and pavement, the pavement condition over the manhole cover, and the size of the manhole cover can significantly affect motorcycle driver maneuvers. Other factors, including traffic conditions, lane width, motorcycle speed, and loading conditions, also have significant effects on motorcycle driver maneuvers. To reduce the effects and potential risks from the manhole covers, highway authorities not only need to make sure that any newly installed manhole covers are as level as possible but also need to regularly maintain all the manhole covers to ensure that they are in good condition. In the long run, the size of manhole covers should be kept as small as possible so that the impact of manhole covers on motorcycle drivers can be effectively reduced. Supplemental materials are available for this article. Go to the publisher

  10. Effect of a hybrid maneuver in treating posterior canal benign paroxysmal positional vertigo.

    Science.gov (United States)

    Badawy, Wanees M A; Gad El-Mawla, Ebtessam K; Chedid, Ahmed E F; Mustafa, Ahmed H A

    2015-02-01

    Benign paroxysmal positional vertigo (BPPV) is the most common disorder of the vestibular system of the inner ear, which is a vital part of maintaining balance. Although the efficacy of the Epley maneuver-also known as the canalith repositioning maneuver (CRM)-is well established, data comparing CRM versus a hybrid treatment are lacking. The purpose of this study was to determine the effect of a hybrid treatment, the Gans repositioning maneuver (GRM) either with or without postmaneuver restrictions, compared with CRM on treatment of posterior canal BPPV (PC-BPPV). Study design was a randomized controlled trial. A total of 45 patients (30 males and 15 females) with unilateral PC-BPPV were randomly allocated to one of three equal groups on the basis of the date of the first visit with matched assignment for gender: a GRMR group (GRM with postmaneuver restrictions), a GRM group, and a CRM group. Patients received weekly administration of the maneuver until resolution of symptoms. The Dix-Hallpike test was performed before treatment at every appointment, and finally after 1 mo from the last maneuver. Nystagmus duration and vertigo intensity were recorded. The supine roll test was performed in case the Dix-Hallpike test was negative to test otoconial migration. Data were analyzed with repeated-measures analysis of variance, paired t-tests with a Bonferroni correction, and the Spearman rank correlation coefficient. All patients showed improvement within the groups, and PC-BPPV symptoms were resolved by an average of 2, 1.7, and 1.6 maneuvers for GRMR, GRM, and CRM, respectively, with no statistical differences among the three groups (p > 0.05). Only two patients had recurrence, and one patient had horizontal BPPV at 1 mo follow-up. We demonstrated that the GRM as a new treatment is effective in treating PC-BPPV with no benefits to postmaneuver restrictions. American Academy of Audiology.

  11. Proximity Operations for Space Situational Awareness Spacecraft Rendezvous and Maneuvering using Numerical Simulations and Fuzzy Logic

    Science.gov (United States)

    Carrico, T.; Langster, T.; Carrico, J.; Alfano, S.; Loucks, M.; Vallado, D.

    The authors present several spacecraft rendezvous and close proximity maneuvering techniques modeled with a high-precision numerical integrator using full force models and closed loop control with a Fuzzy Logic intelligent controller to command the engines. The authors document and compare the maneuvers, fuel use, and other parameters. This paper presents an innovative application of an existing capability to design, simulate and analyze proximity maneuvers; already in use for operational satellites performing other maneuvers. The system has been extended to demonstrate the capability to develop closed loop control laws to maneuver spacecraft in close proximity to another, including stand-off, docking, lunar landing and other operations applicable to space situational awareness, space based surveillance, and operational satellite modeling. The fully integrated end-to-end trajectory ephemerides are available from the authors in electronic ASCII text by request. The benefits of this system include: A realistic physics-based simulation for the development and validation of control laws A collaborative engineering environment for the design, development and tuning of spacecraft law parameters, sizing actuators (i.e., rocket engines), and sensor suite selection. An accurate simulation and visualization to communicate the complexity, criticality, and risk of spacecraft operations. A precise mathematical environment for research and development of future spacecraft maneuvering engineering tasks, operational planning and forensic analysis. A closed loop, knowledge-based control example for proximity operations. This proximity operations modeling and simulation environment will provide a valuable adjunct to programs in military space control, space situational awareness and civil space exploration engineering and decision making processes.

  12. Effects of postural restriction after modified Epley maneuver on recurrence of benign paroxysmal positional vertigo.

    Science.gov (United States)

    Balikci, Hasan Huseyin; Ozbay, Isa

    2014-10-01

    In the present study, we calculated the success rate of the modified Epley maneuver and determined the effectiveness of post-maneuver positional restriction in terms of the prevention of early and late recurrence. The present study was conducted on 78 patients who had unilateral benign paroxysmal positional vertigo (BPPV) of the posterior semicircular canal (SCC) and who were treated in the Otorhinolaryngology Department of Susehri State Hospital. The Dix-Hallpike test was performed on all patients. After the involved canal was identified using this test, we guided patients through the modified Epley repositioning maneuver. A maximum of two maneuvers were performed in the same session. The patients were randomly divided into two groups. One group was not advised any positional restriction, while the second group was advised positional restriction for 10 days after the procedure. Recurrences during 1-90 days after the treatment were noted as early recurrences, while those that occurred after 90 days were noted as late recurrences. In the restriction group (n=39), repositioning was successful after a single maneuver in 32 (82.05%) patients and after two maneuvers in 5 (12.8%) patients. Repositioning failed in two (5.1%) patients. In the non-restriction group (n=39), repositioning was successful after a single maneuver in 31 (79.4%) patients and after two maneuvers in 6 (15.3%) patients. Repositioning failed in two (5.1%) patients. Thus, the success rate was 94.8% in each group. Early recurrence occurred in 3 (8.1%) of 37 patients in the restriction group and 2 (5.4%) of 37 patients in the non-restriction group (p>0.05). Late recurrence occurred in 5 (13.5%) of 37 patients in both the restriction and non-restriction groups (p>0.05). Postural restriction after a canalith repositioning procedure does not improve procedural success or decrease early and late recurrence rates. However, the number of patients was too small to detect a difference between both treatment

  13. Rest-to-Rest Slew Maneuver of Three-Axis Rotational Flexible Spacecraft

    OpenAIRE

    Kim, J.J.; Agrawal, B.N.

    2008-01-01

    The article of record as published may be found at http://dx.doi.org/10.3182/20080706-5-KR-1001.02040 This paper presents a slew maneuver control design of three-axis rotational flexible spacecraft. The focus of the work is to investigate the nonlinear effect of the three axis maneuver for a flexible spacecraft when a vibration suppression technique for linear systems such as input shaping is used in the control design. A simple method of slewing three-axis rotational spacecraft using inpu...

  14. Multiple Vascular Accidents Including Rupture of a Sinus of Valsalva Aneurysm, a Minor Ischemic Stroke and Intracranial Arterial Anomaly in a Patient with Systemic Congenital Abnormalities: A Case Report

    Directory of Open Access Journals (Sweden)

    Masataka Nakajima

    2013-11-01

    Full Text Available A 39-year-old man with a history of rupture of a sinus of Valsalva aneurysm experienced an ischemic stroke. Although the patient presented left-sided hemiparesis for a week, no abnormal signals were indicated on diffusion-weighted imaging with repeated magnetic resonance scans. Carotid ultrasound and cerebral angiography were conducted, and they revealed hypoplasty of the left internal carotid artery with a low-lying carotid bifurcation at the level of the C6 vertebra. In addition, he was diagnosed with intellectual disabilities, evaluated by the Wechsler Adult Intelligence Scale-III, and congenital velopharyngeal insufficiency. We herein present the first report of a patient with cardio-cerebrovascular abnormalities, intellectual disabilities, and an otorhinolaryngological abnormality.

  15. A multinomial-logit ordered-probit model for jointly analyzing crash avoidance maneuvers and crash severity

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    ' propensity to engage in various corrective maneuvers in the case of the critical event of vehicle travelling. Five lateral and speed control maneuvers are considered: “braking”, “steering”, “braking & steering”, and “other maneuvers”, in addition to a “no action” option. The analyzed data are retrieved from...

  16. Pressure applied by the healthcare staff on a cricoids cartilage simulator during Sellick's maneuver in rapid sequence intubation

    NARCIS (Netherlands)

    J.A. Calvache (Jose Andrés); L.C.B. Sandoval (Luz); W.A. Vargas (William Andres)

    2013-01-01

    textabstractBackground: Sellick's maneuver or cricoid pressure is a strategy used to prevent bronchoaspiration during the rapid intubation sequence. Several studies have described that the force required for an adequate maneuver is of 2.5-3.5 kg. The purpose of this paper was to determine the force

  17. Grab them by the Nose and Kick them in the Pants: Patton on Combined Arms Operational Maneuver

    Science.gov (United States)

    2010-04-23

    in order to break through the hedgerows and into the city of A vranches and the plains of Brittany commenced on 25 July 1944. Patton may not have...operational maneuver. Much like the trenches of World War I, the formidable hedgerows in France favored the defender and prevented maneuver. Yet Patton was

  18. 78 FR 11555 - Special Conditions: Embraer S.A., Model EMB-550 Airplane; Design Roll Maneuver for Electronic...

    Science.gov (United States)

    2013-02-19

    ... Law 92-574, the ``Noise Control Act of 1972.'' The FAA issues special conditions, as defined in 14 CFR...; Design Roll Maneuver for Electronic Flight Controls AGENCY: Federal Aviation Administration (FAA), DOT... design roll maneuver for electronic flight controls, specifically an electronic flight control system...

  19. 77 FR 70384 - Special Conditions: Embraer S.A., Model EMB-550 Airplane; Design Roll Maneuver for Electronic...

    Science.gov (United States)

    2012-11-26

    ... Law 92-574, the ``Noise Control Act of 1972.'' The FAA issues special conditions, as defined in 14 CFR... Maneuver for Electronic Flight Controls AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice... design roll maneuver for electronic flight controls, specifically an electronic flight control system...

  20. Analysis of risk factors influencing the outcome of the Epley maneuver.

    Science.gov (United States)

    Domínguez-Durán, E; Domènech-Vadillo, E; Álvarez-Morujo de Sande, M G; González-Aguado, R; Guerra-Jiménez, G; Ramos-Macías, Á; Morales-Angulo, C; Martín-Mateos, A J; Figuerola-Massana, E; Galera-Ruiz, H

    2017-10-01

    Benign paroxysmal positional vertigo (BPPV) is the most frequent type of vertigo. The treatment of canalithiasis of the posterior semicircular canal consists in performing a particle-repositioning maneuver, such as the Epley maneuver (EM). However, the EM is not effective in all cases. The objective of this study is to identify risk factors, which predict the EM failure, among the clinical variables recorded in anamnesis and patient examination. This is an observational prospective multicentric study. All patients presenting with BPPV were recruited and applied the EM and appointed for a follow-up visit 7 days later. The following variables were recorded: sex, age, arterial hypertension, diabetes, hyperlipidemia, smoking habit, alcohol consumption, migraine, osteoporosis, diseases of the inner ear, previous ipsilateral BPPV, previous traumatic brain injury, previous sudden head deceleration, time of evolution, sulpiride or betahistine treatment, experienced symptoms, outcome of the Halmagyi maneuver, laterality, cephalic hyperextension of the neck, intensity of nystagmus, intensity of vertigo, duration of nystagmus, occurrence of orthotropic nystagmus, symptoms immediately after the EM, postural restrictions, and symptoms 7 days after the EM. Significant differences in the rate of loss of nystagmus were found for six variables: hyperlipidemia, previous ipsilateral BPPV, intensity of nystagmus, duration of nystagmus, post-maneuver sweating, and subjective status. The most useful significant variables in the clinical practice to predict the success of the EM are previous BPPV and intensity of nystagmus. In the other significant variables, no physiopathological hypothesis can be formulated or differences between groups are too small.

  1. Four-Impulsive Rendezvous Maneuvers for Spacecrafts in Circular Orbits Using Genetic Algorithms

    Directory of Open Access Journals (Sweden)

    Denilson Paulo Souza dos Santos

    2012-01-01

    Full Text Available Spacecraft maneuvers is a very important topic in aerospace engineering activities today. In a more generic way, a spacecraft maneuver has the objective of transferring a spacecraft from one orbit to another, taking into account some restrictions. In the present paper, the problem of rendezvous is considered. In this type of problem, it is necessary to transfer a spacecraft from one orbit to another, but with the extra constraint of meeting another spacecraft when reaching the final orbit. In particular, the present paper aims to analyze rendezvous maneuvers between two coplanar circular orbits, seeking to perform this transfer with lowest possible fuel consumption, assuming that this problem is time-free and using four burns during the process. The assumption of four burns is used to represent a constraint posed by a real mission. Then, a genetic algorithm is used to solve the problem. After that, a study is made for a maneuver that will make a spacecraft to encounter a planet, in order to make a close approach that will change its energy. Several simulations are presented.

  2. Multislice spiral computed tomography to determine the effects of a recruitment maneuver in experimental lung injury

    Energy Technology Data Exchange (ETDEWEB)

    Henzler, Dietrich; Rossaint, Rolf [University Hospital, RWTH Aachen, Anesthesiology Department, Aachen (Germany); Mahnken, Andreas H.; Wildberger, Joachim E.; Guenther, Rolf W. [University Hospital of the RWTH Aachen, Clinic of Diagnostic Radiology, Aachen (Germany); Kuhlen, Ralf [University Hospital of the RWTH Aachen, Operative Intensive Care Department, Aachen (Germany)

    2006-06-15

    Although recruitment of atelectatic lung is a common aim in acute respiratory distress syndrome (ARDS), the effects of a recruitment maneuver have not been assessed quantitatively. By multislice spiral CT (MSCT), we analyzed the changes in lung volumes calculated from the changes in the CT values of hyperinflated (V{sub HYP}), normally (V{sub NORM}), poorly (V{sub POOR}) and nonaerated (V{sub NON}) lung in eight mechanically ventilated pigs with saline lavage-induced acute lung injury before and after a recruitment maneuver. This was compared to single slice analysis near the diaphragm. The increase in aerated lung was mainly for V{sub POOR} and the less in V{sub NORM}. Total lung volume and intrathoracic gas increased. No differences were found for tidal volumes measured by spirometry or determined by CT. The inspiratory-expiratory volume differences were not different after the recruitment maneuver in V{sub NON} (from 62{+-}18 ml to 43{+-}26 ml, P=0.114), and in V{sub NORM} (from 216{+-}51 ml to 251{+-}37 ml, P=0.102). Single slice analysis significantly underestimated the increase in normally and poorly aerated lung. Quantitative analysis of lung volumes by whole lung MSCT revealed the increase of poorly aerated lung as the main mechanism of a standard recruitment maneuver. MSCT can provide additional information as compared to single slice CT. (orig.)

  3. X-48B Phase 1 Flight Maneuver Database and ICP Airspace Constraint Analysis

    Science.gov (United States)

    Fast, Peter Alan

    2010-01-01

    The work preformed during the Summer 2010 by Peter Fast. The main tasks assigned were to update and improve the X-48 Flight Maneuver Database and conduct an Airspace Constraint Analysis for the Remotely Operated Aircraft Area used to flight test Unmanned Arial Vehicles. The final task was to develop and demonstrate a working knowledge of flight control theory.

  4. Optimized routing on agricultural fields by minimizing maneuvering and servicing time

    NARCIS (Netherlands)

    Spekken, M.; Bruin, de S.

    2013-01-01

    Agricultural machines spend a significant part of their time on non-productive operations such as maneuvering near the boundaries of the field and loading or offloading of inputs or outputs (here referred to as servicing). This paper integrates existing methods for route optimization so as to

  5. Cooperative maneuvering in close environments among cybercars and dual-mode cars

    NARCIS (Netherlands)

    Milanés, V.; Alonso, J.; Bouraoui, L.; Ploeg, J.

    2011-01-01

    This paper describes the results of vehicle-to-vehicle (V2V) and infrastructure-to-vehicle (I2V) experiments implementing cooperative maneuvering for three different vehicles driving automatically. The cars used were cybercars from the Institut National de Recherche en Informatique et Automatique

  6. Adaptive lyapunov control and artificial neural networks for spacecraft relative maneuvering using atmospheric differential drag

    Science.gov (United States)

    Perez Chaparro, David Andres

    At low Earth orbits, a differential in the drag acceleration between spacecraft can be used to control their relative motion. This drag differential allows for a propellant-free alternative to thrusters for performing relative maneuvers in these orbits. The interest in autonomous propellant-less maneuvering comes from the desire to reduce the costs of spacecraft formations. Formation maneuvering opens up a wide variety of new applications for spacecraft missions, such as on-orbit maintenance and refueling. In this work atmospheric differential drag based nonlinear controllers are presented that can be used for virtually any planar relative maneuver of two spacecraft, provided that there is enough atmospheric density and that the spacecraft can change their ballistic coefficients by sufficient amounts to generate the necessary differential accelerations. The control techniques are successfully tested using high fidelity Satellite Tool Kit simulations for re-phase, fly-around, and rendezvous maneuvers, proving the feasibility of the proposed approach for a real flight. Furthermore, the atmospheric density varies in time and in space as the spacecraft travel along their orbits. The ability to accurately forecast the density allows for accurate onboard orbit propagation and for creating realistic guidance trajectories for maneuvers that rely on the differential drag. In this work a localized density predictor based on artificial neural networks is also presented. The predictor uses density measurements or estimates along the past orbits and can use a set of proxies for solar and geomagnetic activities to predict the value of the density along the future orbits of the spacecraft. The performance of the localized predictor is studied for different neural network structures, testing periods of high and low solar and geomagnetic activities and different prediction windows. Comparison with previously developed methods show substantial benefits in using neural networks, both

  7. Kinematics and shoulder belt position of child anthropomorphic test devices during steering maneuvers.

    Science.gov (United States)

    Stockman, Isabelle; Bohman, Katarina; Jakobsson, Lotta

    2013-01-01

    The objective of this study was to quantify and compare the kinematics and shoulder belt position of child anthropomorphic test devices (ATDs) during emergency steering maneuvers. Furthermore, the ATDs were compared to the results from child volunteers aged 4 to 12 in the same test setup (Bohman, Stockman, et al. 2011). A driving study was conducted on a test track comprising 4 ATDs: the Q6, Q10, and Hybrid III (HIII) 6- and 10-year-old ATDs restrained in the rear seat of a passenger vehicle. The ATDs were exposed to 2 repeated steering maneuvers in each restraint system. The Q6 and HIII 6-year-old were restrained on booster cushions as well as high-back booster seats. The Q10 and HIII 10-year-old were restrained on booster cushions or restrained by 3-point seat belts directly on the seat. Lateral motion of the forehead and upper sternum was determined, as well as shoulder belt movement on shoulder and torso tilting angle. All ATDs began to move approximately at the same point in time corresponding to a vehicle lateral acceleration of just below 0.2 g. In the later phase of the maneuver, Q10 had moved 26 percent less than the children when restrained by seat belt only and 35 percent less when on a booster cushion. Corresponding numbers for the HIII 10-year-old were 43 and 44 percent higher than for children. Compared to children, the Q6 had moved 34 percent less when restrained on a high-back booster seat and 31 percent less when on a booster cushion. Corresponding numbers for HIII 6-year-old were 7 and 28 percent higher than for children. Due to extensive variety of lateral displacements observed in the children, child performance range covers both ATD families for the evaluated sizes of 6- and 10-year-old ATDs. Compared to children, the HIII ATDs were closer with regards to mean values in the initial phase of the maneuver and the Q ATDs were closer in the end of the ramping phase of the lateral acceleration. The question regarding which ATD replicates better the

  8. Quality of intrapartum care by skilled birth attendants in a refugee clinic on the Thai-Myanmar border: a survey using WHO Safe Motherhood Needs Assessment.

    Science.gov (United States)

    Hoogenboom, Gabie; Thwin, May Myo; Velink, Kris; Baaijens, Marijke; Charrunwatthana, Prakaykaew; Nosten, François; McGready, Rose

    2015-02-05

    Increasing the number of women birthing with skilled birth attendants (SBAs) as one of the strategies to reduce maternal mortality and morbidity must be partnered with a minimum standard of care. This manuscript describes the quality of intrapartum care provided by SBAs in Mae La camp, a low resource, protracted refugee context on the Thai-Myanmar border. In the obstetric department of Shoklo Malaria Research Unit (SMRU) the standardized WHO Safe Motherhood Needs Assessment tool was adapted to the setting and used: to assess the facility; interview SBAs; collect data from maternal records during a one year period (August 2007 - 2008); and observe practice during labour and childbirth. The facility assessment recorded no 'out of stock' or 'out of date' drugs and supplies, equipment was in operating order and necessary infrastructure e.g. a stand-by emergency car, was present. Syphilis testing was not available. SBA interviews established that danger signs and symptoms were recognized except for sepsis and endometritis. All SBAs acknowledged receiving theoretical and 'hands-on' training and regularly attended deliveries. Scores for the essential elements of antenatal care from maternal records were high (>90%) e.g. providing supplements, recording risk factors as well as regular and correct partogram use. Observed good clinical practice included: presence of a support person; active management of third stage; post-partum monitoring; and immediate and correct neonatal care. Observed incorrect practice included: improper controlled cord traction; inadequate hand washing; an episiotomy rate in nulliparous women 49% (34/70) and low rates 30% (6/20) of newborn monitoring in the first hours following birth. Overall observed complications during labour and birth were low with post-partum haemorrhage being the most common in which case the SBAs followed the protocol but were slow to recognize severity and take action. In the clinic of SMRU in Mae La refugee camp, SBAs were

  9. The Choice of the Maneuver of the Vessel’s Passing Considering the Coordination’s System of the Interactive Vessels and Their Dynamic Characteristics

    Directory of Open Access Journals (Sweden)

    Yevgen Volkov

    2017-03-01

    Full Text Available The maneuver of the altering course of the vessel is a more preferable to avoid a collision. Due to that the calculation of the parameters of the avoidance maneuver should be done considering the dynamic characteristics of the vessel in maneuvering. The paper analyzes the dynamic models of the vessel rotation motion in order to select more appropriate one for the calculation of avoidance maneuver of the vessel applying the altering of the course.

  10. Parameter Identification of Ship Maneuvering Models Using Recursive Least Square Method Based on Support Vector Machines

    Directory of Open Access Journals (Sweden)

    Man Zhu

    2017-03-01

    Full Text Available Determination of ship maneuvering models is a tough task of ship maneuverability prediction. Among several prime approaches of estimating ship maneuvering models, system identification combined with the full-scale or free- running model test is preferred. In this contribution, real-time system identification programs using recursive identification method, such as the recursive least square method (RLS, are exerted for on-line identification of ship maneuvering models. However, this method seriously depends on the objects of study and initial values of identified parameters. To overcome this, an intelligent technology, i.e., support vector machines (SVM, is firstly used to estimate initial values of the identified parameters with finite samples. As real measured motion data of the Mariner class ship always involve noise from sensors and external disturbances, the zigzag simulation test data include a substantial quantity of Gaussian white noise. Wavelet method and empirical mode decomposition (EMD are used to filter the data corrupted by noise, respectively. The choice of the sample number for SVM to decide initial values of identified parameters is extensively discussed and analyzed. With de-noised motion data as input-output training samples, parameters of ship maneuvering models are estimated using RLS and SVM-RLS, respectively. The comparison between identification results and true values of parameters demonstrates that both the identified ship maneuvering models from RLS and SVM-RLS have reasonable agreements with simulated motions of the ship, and the increment of the sample for SVM positively affects the identification results. Furthermore, SVM-RLS using data de-noised by EMD shows the highest accuracy and best convergence.

  11. Concept of a Maneuvering Load Control System and Effect on the Fatigue Life Extension

    Directory of Open Access Journals (Sweden)

    N. Paletta

    Full Text Available Abstract This paper presents a methodology for the conceptual design of a Maneuver Load Control system taking into account the airframe flexibility. The system, when switched on, is able to minimize the bending moment augmentation at a wing station near the wing root during an unsteady longitudinal maneuver. The reduction of the incremental wing bending moment due to maneuvers can lead to benefits such as improved pay-loads/gross weight capabilities and/or extended structural fatigue life. The maneuver is performed by following a desired vertical load factor law with elevators deflections, starting from the trim equilibrium in level flight. The system observes load factor and structural bending through accelerometers and calibrated strain sensors and then sends signals to a computer that symmetrically actuates ailerons for reducing the structural bending and elevators for compensating the perturbation to the longitudinal equilibrium. The major limit of this kind of systems appears when it has to be installed on commercial transport aircraft for reduced OEW or augmented wing aspect-ratio. In this case extensive RAMS analyses and high redundancy of the MLC related sub-systems are required by the Certification Authority. Otherwise the structural design must be performed at system off. Thus the unique actual benefit to be gained from the adoption of a MLC system on a commercial transport is the fatigue life extension. An application to a business aircraft responding to the EASA Certification Specifications, Part 25, has been performed. The aircraft used for the numerical application is considered only as a test case-study. Most of design and analysis considerations are applicable also to other aircraft, such as unmanned or military ones, although some design requirements can be clearly different. The estimation of the fatigue life extension of a structural joint (wing lower skin-stringer, located close to the wing root, has been estimated by showing

  12. Precision Closed-Loop Orbital Maneuvering System Design and Performance for the Magnetospheric Multi-Scale Mission (MMS) Formation

    Science.gov (United States)

    Chai, Dean; Queen, Steve; Placanica, Sam

    2015-01-01

    NASA's Magnetospheric Multi-Scale (MMS) mission successfully launched on March 13, 2015 (UTC) consists of four identically instrumented spin-stabilized observatories that function as a constellation to study magnetic reconnection in space. The need to maintain sufficiently accurate spatial and temporal formation resolution of the observatories must be balanced against the logistical constraints of executing overly-frequent maneuvers on a small fleet of spacecraft. These two considerations make for an extremely challenging maneuver design problem. This paper focuses on the design elements of a 6-DOF spacecraft attitude control and maneuvering system capable of delivering the high-precision adjustments required by the constellation designers---specifically, the design, implementation, and on-orbit performance of the closed-loop formation-class maneuvers that include initialization, maintenance, and re-sizing. The maneuvering control system flown on MMS utilizes a micro-gravity resolution accelerometer sampled at a high rate in order to achieve closed-loop velocity tracking of an inertial target with arc-minute directional and millimeter-per-second magnitude accuracy. This paper summarizes the techniques used for correcting bias drift, sensor-head offsets, and centripetal aliasing in the acceleration measurements. It also discusses the on-board pre-maneuver calibration and compensation algorithms as well as the implementation of the post-maneuver attitude adjustments.

  13. Maternal intrapartum antibiotic treatment continues to exert a bactericidal effect on the umbilical cord and peripheral venous blood of newborn infants.

    Science.gov (United States)

    Hershkovich-Shporen, C; Bardenstein, R; Blickstein, I; Shinwell, E S; Flidel-Rimon, O

    2017-11-01

    It is unclear whether maternal intrapartum antibiotic treatment (IAT) continues to exert a bactericidal effect on common pathogens in neonates. We studied the in vitro bactericidal effect of IAT on the cord and peripheral venous blood of newborn infants. Umbilical cord and peripheral venous blood from newborn infants born at Kaplan Medical Center, Israel, from April to October 2014 were studied for serum bactericidal titres against Group B Streptococcus (GBS) and Escherichia coli (E. coli) strains. We studied 60 samples of umbilical cord blood and 18 samples of peripheral venous blood from 60 newborn infants whose mothers received IAT. The controls were 10 samples of cord blood from mothers without IAT. Cord blood exerted a bactericidal effect against 98% of GBS isolates but only 8% of E.coli isolates. Peripheral blood exerted a bactericidal effect against GBS in 94% of cases, but not against E. coli. No bactericidal effect was seen in the blood from the controls. We found a continued bactericidal effect of umbilical cord blood and neonatal peripheral blood from newborn infants of IAT-treated mothers, mainly against GBS, but rarely against E. Coli. These findings may assist clinicians treating at-risk infants exposed to IAT. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  14. Effects of intrapartum epidural analgesia at high altitudes: maternal, fetal, and neonatal outcomes. A randomized controlled trial of two formulations of analgesics.

    Science.gov (United States)

    Shokry, Mahmoud; Manaa, Essam M; Shoukry, Randa Ali; Shokeir, Mohamed Hossam; Elsedfy, Ghada O; Abd El-Aziz, Abd El-Salam

    2010-07-01

    To investigate whether intrapartum epidural analgesics (bupivacaine or ropivacaine) have an influence (safety and efficacy) on mothers, fetuses, or newborns at high altitudes (2,200 m above the sea level). Prospective randomized trial. A tertiary referral hospital in Aseer region, Saudi Arabia. Eighty parturient women with normal full term pregnancy (37-40 weeks) were randomly allocated to a group receiving epidural bupivacaine 0.125% and the other receiving ropivacaine 0.2%, with fentanyl 100 microg given to both groups. Intra- and postpartum clinical management of the pregnant women and newborns and fetal Doppler assessments were performed. Severity of pain, onset and duration of analgesia, and occurrence of motor blockade were primary outcomes. Progress of labor, need for oxytocin augmentation, mode of delivery, and neonatal condition were secondary outcomes. Demographic, labor characteristics, and neonatal outcomes of the two groups were comparable. The onset of analgesia was relatively more rapid for ropivacaine group (p = 0.067). Duration of analgesia after the first bolus dose was longer and the need for supplemental epidural analgesic doses was lesser in the bupivacaine group (p = 0.041 and 0.045, respectively). In both groups, the fetal umbilical and middle cerebral artery pulsatility indices showed significant change when compared to the baseline of the same group. At high altitudes, no major advantage was found for epidural ropivacaine over bupivacaine in addition to fentanyl for labor analgesia and no harmful effects of the medications were found on mothers, fetuses, or newborns.

  15. Application of hybrid methodology to rotors in steady and maneuvering flight

    Science.gov (United States)

    Rajmohan, Nischint

    Helicopters are versatile flying machines that have capabilities that are unparalleled by fixed wing aircraft, such as operating in hover, performing vertical takeoff and landing on unprepared sites. This makes their use especially desirable in military and search-and-rescue operations. However, modern helicopters still suffer from high levels of noise and vibration caused by the physical phenomena occurring in the vicinity of the rotor blades. Therefore, improvement in rotorcraft design to reduce the noise and vibration levels requires understanding of the underlying physical phenomena, and accurate prediction capabilities of the resulting rotorcraft aeromechanics. The goal of this research is to study the aeromechanics of rotors in steady and maneuvering flight using hybrid Computational Fluid Dynamics (CFD) methodology. The hybrid CFD methodology uses the Navier-Stokes equations to solve the flow near the blade surface but the effect of the far wake is computed through the wake model. The hybrid CFD methodology is computationally efficient and its wake modeling approach is nondissipative making it an attractive tool to study rotorcraft aeromechanics. Several enhancements were made to the CFD methodology and it was coupled to a Computational Structural Dynamics (CSD) methodology to perform a trimmed aeroelastic analysis of a rotor in forward flight. The coupling analyses, both loose and tight were used to identify the key physical phenomena that affect rotors in different steady flight regimes. The modeling enhancements improved the airloads predictions for a variety of flight conditions. It was found that the tightly coupled method did not impact the loads significantly for steady flight conditions compared to the loosely coupled method. The coupling methodology was extended to maneuvering flight analysis by enhancing the computational and structural models to handle non-periodic flight conditions and vehicle motions in time accurate mode. The flight test

  16. Analysis, Validation, Prediction And Fundamental Understanding Of Rotor Blade Loads In An Unsteady Maneuver

    Science.gov (United States)

    Abhishek, Abhishek

    This study predicts, analyzes, and isolates the mechanisms of main rotor airloads, structural loads, and swashplate servo loads in a severe unsteady maneuver. The objective is, to develop a comprehensive transient rotor analysis for predicting maneuver loads. The main rotor structural loads encountered during unsteady maneuvers are important to size different critical components of the rotor system, particularly for advanced combat helicopters. These include the blade structural loads, control/pitch-link loads, and swashplate servo loads. Accurate and consistent prediction of maneuver loads is necessary to reduce the risks and costs associated with use of prior flight test data as a basis for design. The mechanism of rotor loads in different level flight regimes is well understood -- transonic shock in high speed flight, inter-twinning of blade tip vortices below the rotor disk at low speed transonic flight, and two dynamic stall cycles on retreating blade during high altitude dynamic stall flight. All these physical phenomena can occur simultaneously during a maneuver. The goal is to understand the key mechanisms involved in maneuver and model them accurately. To achieve this, the aerodynamics and structural dynamics of UH-60A rotor in unsteady maneuvering flight is studied separately. For identification of prediction deficiencies in each, first, the measured lift, drag, pitching moment and damper force from the UH-60A Flight Test Program for UTTAS pull-up maneuver (C11029: 2.16g pull-up maneuver) are used to obtain an accurate set of deformations. A multibody finite element blade model, developed for this purpose, is used to perform measured airloads analysis. Next, the resultant blade deformations are used to predict the airloads using lifting-line and RANS CFD aerodynamic models. Both lifting-line as well as CFD analyses predict all three stall cycles with prescribed deformations. From the airloads predicted using prescribed deformations, it is established that

  17. Development of an intelligent neuro-fuzzy maneuver identification system for autonomous aircraft

    Science.gov (United States)

    Krishnamurthy, Karthik

    2000-10-01

    This dissertation reports an investigation of the design of intelligent systems for the high-level control of autonomous aircraft. In a departure from recent work in this field, an attempt has been made to synthesize a high-level control architecture that emulates a human pilot's reasoning capabilities. The system architecture uses pilot-type classifications of aircraft modes (the various maneuvers that pilots are trained to execute) within all decision-making and reasoning processes. A flight control system structured in terms of these modes offers scope for efficient combination of concepts from artificial intelligence, control theory and aviation practice. A critical component of this intelligent flight controller is an automated mode inference system. This innovative system extracts high-level knowledge of the current maneuver (or segment of the overall mission) from sensed measurements of dynamic state variables. Using a blend of soft computing approaches, this inference engine consistently identifies the correct maneuver being flown, even in the presence of moderate sensor noise and data ambiguities. In the process of creating this inference engine, a novel scheme to generate training data sets for neural networks has been developed. This data generation scheme permits complete coverage of the aircraft's capability envelope; this coverage is achieved without recourse to the voluminous flight data (actual or simulated) normally required to train neural networks. The data generation scheme thus significantly reduces developmental effort. Apart from this innovation, pilot-like techniques to cope with the phenomenon of chatter (where identification rapidly switches back-and-forth between modes) have been developed and implemented within the inference system. This dissertation also discusses the development of logic to interpret and implement commands from remote operators, using high-level knowledge of the current mission segment. This knowledge is used to

  18. Early Mission Maneuver Operations for the Deep Space Climate Observatory Sun-Earth L1 Libration Point Mission

    Science.gov (United States)

    Roberts, Craig; Case, Sara; Reagoso, John; Webster, Cassandra

    2015-01-01

    The Deep Space Climate Observatory mission launched on February 11, 2015, and inserted onto a transfer trajectory toward a Lissajous orbit around the Sun-Earth L1 libration point. This paper presents an overview of the baseline transfer orbit and early mission maneuver operations leading up to the start of nominal science orbit operations. In particular, the analysis and performance of the spacecraft insertion, mid-course correction maneuvers, and the deep-space Lissajous orbit insertion maneuvers are discussed, com-paring the baseline orbit with actual mission results and highlighting mission and operations constraints..

  19. Time-History Data of Maneuvers Performed by a Republic F84G Airplane During Squadron Operational Training

    Science.gov (United States)

    Hamer, Harold A.; Mayo, Alton P.

    1953-01-01

    Preliminary results of one phase of a control-motion study program involving several jet fighter-type airplanes are presented in time-history form and are summarized as maximum measured quantities plotted against indicated airspeed. The results pertain to approximately 1,000 maneuvers performed by a Republic F-84G jet-fighter airplane during squadron operational training. The data include most tactical maneuvers of which the F-84G airplane is capable. Maneuvers were performed at pressure altitudes of 0 to 30,000 feet with indicated airspeeds ranging from the stalling speed to approximately 515 knots.

  20. Less cost by using hanging maneuver and Pringle maneuver in left lateral hepatectomy through small laparotomy wound--experience of Southern Taiwan.

    Science.gov (United States)

    Lin, Ting-Lung; Alikhanov, Ruslan; Kuo, Sheng-Chih; Li, Wei-Feng; Chen, Chao-Long; Wang, Shih-Ho; Lin, Chih-Che; Liu, Yueh-Wei; Yong, Chee-Chien; Lin, Yu-Hung; Wang, Chih-Chi

    2016-01-08

    Laparoscopic segmentectomy for liver tumor located in the left lateral segment (LLS) is thought to be a standard protocol nowadays with several advantages, such as small wound, few blood loss, and short hospital stay. However, there are still many disadvantages during executing laparoscopic LLS segmentectomy. This manuscript aims to present the technique to execute LLS segmentectomy with small incision, hanging maneuver without Pringle maneuver in patients with tumor at LLS of the liver. Between November 2010 and July 2011, hepatectomies through small incision for nine patients with benign and malignant tumors were performed at Kaohsiung Chang Gung Memorial Hospital, Taiwan. Perioperative and postoperative results, such as operation time, blood loss, incisional width, and postoperative stay were used to determine consequents for this technique. Results demonstrated that modified LLS segmentectomy by the author's team was performed successfully in patient with liver tumor with fewer blood loss, smaller incisional width, and lower hospital cost than traditional open surgery. In addition, the instrument cost and blood loss in our series were less than that in laparoscopic LLS segmentectomy in published literature. Authors concluded that minimally incisional segmentectomy, with less cost and technical demanding, could be an alternative choice in patient with liver tumor at LLS.

  1. Evaluation of the Trade Space Between UAS Maneuver Performance and SAA System Performance Requirements

    Science.gov (United States)

    Jack, Devin P.; Hoffler, Keith D.; Johnson, Sally C.

    2014-01-01

    A need exists to safely integrate Unmanned Aircraft Systems (UAS) into the National Airspace System. Replacing manned aircraft's see-and-avoid capability in the absence of an onboard pilot is one of the key challenges associated with safe integration. Sense-and-avoid (SAA) systems will have to achieve yet-to-be-determined required separation distances for a wide range of encounters. They will also need to account for the maneuver performance of the UAS they are paired with. The work described in this paper is aimed at developing an understanding of the trade space between UAS maneuver performance and SAA system performance requirements. An assessment of current manned and unmanned aircraft performance was used to establish potential UAS performance test matrix bounds. Then, nearterm UAS integration work was used to narrow down the scope. A simulator was developed with sufficient fidelity to assess SAA system performance requirements for a wide range of encounters. The simulator generates closest-point-of-approach (CPA) data from the wide range of UAS performance models maneuvering against a single intruder with various encounter geometries. The simulator is described herein and has both a graphical user interface and batch interface to support detailed analysis of individual UAS encounters and macro analysis of a very large set of UAS and encounter models, respectively. Results from the simulator using approximate performance data from a well-known manned aircraft is presented to provide insight into the problem and as verification and validation of the simulator. Analysis of climb, descent, and level turn maneuvers to avoid a collision is presented. Noting the diversity of backgrounds in the UAS community, a description of the UAS aerodynamic and propulsive design and performance parameters is included. Initial attempts to model the results made it clear that developing maneuver performance groups is required. Discussion of the performance groups developed and how

  2. An Iterative Learning Control Technique for Point-to-Point Maneuvers Applied on an Overhead Crane

    Directory of Open Access Journals (Sweden)

    Khaled A. Alhazza

    2014-01-01

    Full Text Available An iterative learning control (ILC strategy is proposed, and implemented on simple pendulum and double pendulum models of an overhead crane undergoing simultaneous traveling and hoisting maneuvers. The approach is based on generating shaped commands using the full nonlinear equations of motion combined with the iterative learning control, to use as acceleration commands to the jib of the crane. These acceleration commands are tuned to eliminate residual oscillations in rest-to-rest maneuvers. The performance of the proposed strategy is tested using an experimental scaled model of an overhead crane with hoisting. The shaped command is derived analytically and validated experimentally. Results obtained showed that the proposed ILC control strategy is capable of eliminating travel and residual oscillations in simple and double pendulum models with hoisting. It is also shown, in all cases, that the proposed approach has a low sensitivity to the initial cable lengths.

  3. Axial offset as measure of stability of light water nuclear reactor during capacity maneuvering

    Directory of Open Access Journals (Sweden)

    Mark V. Nikolsky

    2015-03-01

    Full Text Available High reliability and security of power unit are required during operation of power unit while maneuvering. They depend on the stability of reactor when transition from one power level to another. The axial offset is a quantitative measure of the reactor stability. It is shown that change of the active core inlet coolant temperature yields an uncontrollable disturbance affecting the axial offset and therefore the reactor stability. To insure the reactor stability the compromise-combined power control method is proposed. Analysis of the influence of temperature of coolant at the magnitude of the axial offset for different regulatory programs is carried out. The change in the depth of immersion of regulators in the active zone for different regulatory programs when the reactor plant daily capacity maneuver is studied.

  4. Hybrid Switching Controller Design for the Maneuvering and Transit of a Training Ship

    Directory of Open Access Journals (Sweden)

    Tomera Mirosław

    2017-03-01

    Full Text Available The paper presents the design of a hybrid controller used to control the movement of a ship in different operating modes, thereby improving the performance of basic maneuvers. This task requires integrating several operating modes, such as maneuvering the ship at low speeds, steering the ship at different speeds in the course or along the trajectory, and stopping the ship on the route. These modes are executed by five component controllers switched on and off by the supervisor depending on the type of operation performed. The desired route, containing the coordinates of waypoints and tasks performed along consecutive segments of the reference trajectory, is obtained by the supervisory system from the system operator. The former supports switching between component controllers and provides them with new set-points after each change in the reference trajectory segment, thereby ensuring stable operation of the entire hybrid switching controller.

  5. Dynamics and configuration control of the Maneuvering-Net Space Robot System

    Science.gov (United States)

    Huang, Panfeng; Zhang, Fan; Ma, Jun; Meng, Zhongjie; Liu, Zhengxiong

    2015-02-01

    In order to eliminate the limitation of the Space Tether-Net System in the field of maneuver and control, we propose the Maneuvering-Net Space Robot System (MNSRS) in this paper, which can capture and remove the space debris dexterously. We focus on the approaching phase towards the space debris, which is a challenging problem for the MNSRS, especially the coupled dynamics modeling and configuration control problems. Firstly the system and mission overview of the MNSRS is described in detail. After that, a coupled dynamics modeling, which divides the MNSRS into finite mass points connected with massless springs, is established to describe dynamic characteristics of the MNSRS in approaching phase. Then the configuration variation of the MNSRS in approaching phase is analyzed. Finally the configuration control of the MNSRS in approaching phase is investigated.

  6. Monte Carlo Analysis of the Commissioning Phase Maneuvers of the Soil Moisture Active Passive (SMAP) Mission

    Science.gov (United States)

    Williams, Jessica L.; Bhat, Ramachandra S.; You, Tung-Han

    2012-01-01

    The Soil Moisture Active Passive (SMAP) mission will perform soil moisture content and freeze/thaw state observations from a low-Earth orbit. The observatory is scheduled to launch in October 2014 and will perform observations from a near-polar, frozen, and sun-synchronous Science Orbit for a 3-year data collection mission. At launch, the observatory is delivered to an Injection Orbit that is biased below the Science Orbit; the spacecraft will maneuver to the Science Orbit during the mission Commissioning Phase. The delta V needed to maneuver from the Injection Orbit to the Science Orbit is computed statistically via a Monte Carlo simulation; the 99th percentile delta V (delta V99) is carried as a line item in the mission delta V budget. This paper details the simulation and analysis performed to compute this figure and the delta V99 computed per current mission parameters.

  7. Quadcopter Aggressive Maneuvers along Singular Configurations: An Energy-Quaternion Based Approach

    Directory of Open Access Journals (Sweden)

    Ayman A. El-Badawy

    2016-01-01

    Full Text Available Automatic aggressive maneuvers with quadcopters are regarded as a highly challenging control problem. The aim is to tackle the singularities that exist in a vertical looping maneuver. Modeling singularities are resolved by writing the equations-of-motion of the quadcopter in quaternion form. Physical singularities due to underactuation are resolved by using an energy-based control. Energy-based control is utilized to overcome the uncontrollability of the quadcopter at physical singular configurations, for instance, when commanding the quadcopter to gain altitude while pitched at 90∘. Three looping strategies (circular, clothoidal, and newly developed constant thrust are implemented on a nonlinear model of the quadcopter. The three looping strategies are discussed along with their advantages and limitations.

  8. Maneuvering Target Detection Based on JRC System in Gaussian and Non-Gaussian Clutter

    Directory of Open Access Journals (Sweden)

    Yu Yao

    2015-01-01

    Full Text Available Aimed at the problem of detecting maneuvering targets in the Gaussian and sea clutter environments and based on the established motion state model, this paper proposed a new scheme that uses a joint radar-communication (JRC system with Kalman filter to accurately detect the target with the generalized likelihood ratio test (GLRT theory and a constant false alarm rate (CFAR based threshold. Also, the theoretical threshold and probability function of GLRT target detection based on CFAR were given. Moreover, target detection probability of the new JRC system in Weibull and K distribution clutter is deduced. In addition to theoretical considerations, simulations and measurement results of the new JRC systems demonstrate excellent detection performance for maneuvering targets in the Weibull and K distribution channel.

  9. Purging using the Heimlich maneuver among children and adolescents with eating disorders.

    Science.gov (United States)

    Boachie, Ahmed; Kusi Appiah, Edigna; Jubin, Michelle; Jasper, Karin

    2015-09-01

    This case report describes five independent cases of children and adolescents assessed for eating disorders who disclosed using the Heimlich maneuver as a purging technique. The maneuver is meant to be used only in life or death situations, likely once or less in any person's lifetime. A child or adolescent with an eating disorder may be using it to self-induce vomiting on a daily basis, increasing the risk of complications, including potential damage to major organs of the body. Asking patients who purge to elaborate on the methods with which they purge can provide clinicians with fuller information, improving their ability to select appropriate medical tests and interventions. Thorough investigations of physical complaints during the patient assessment may be warranted, including examining patients for possible rib fractures, hemorrhages, perforations of the hollow viscous, and other forms of blunt abdominal traumas. © 2015 Wiley Periodicals, Inc.

  10. Implementation of the Orbital Maneuvering Systems Engine and Thrust Vector Control for the European Service Module

    Science.gov (United States)

    Millard, Jon

    2014-01-01

    The European Space Agency (ESA) has entered into a partnership with the National Aeronautics and Space Administration (NASA) to develop and provide the Service Module (SM) for the Orion Multipurpose Crew Vehicle (MPCV) Program. The European Service Module (ESM) will provide main engine thrust by utilizing the Space Shuttle Program Orbital Maneuvering System Engine (OMS-E). Thrust Vector Control (TVC) of the OMS-E will be provided by the Orbital Maneuvering System (OMS) TVC, also used during the Space Shuttle Program. NASA will be providing the OMS-E and OMS TVC to ESA as Government Furnished Equipment (GFE) to integrate into the ESM. This presentation will describe the OMS-E and OMS TVC and discuss the implementation of the hardware for the ESM.

  11. Analysis of LFM-waveform Libraries for Cognitive Tracking Maneuvering Targets

    Directory of Open Access Journals (Sweden)

    Wang Hongyan

    2016-01-01

    Full Text Available Based on the idea of the waveform agility in cognitive radars,the waveform libraries for maneuvering target tracking are discussed. LFM-waveform libraries are designed according to different combinations of chirp parameters and FrFT rotation angles. By applying the interact multiple model (IMM algorithm in tracking maneuvering targets, transmitted waveform is called real time from the LFM-waveform libraries. The waveforms are selected from the library according to the criterion of maximum mutual information between the current state of knowledge of the model and the measurement. Simulation results show that waveform library containing certain amount LFM-waveforms can improve the performance of cognitive tracking radar.

  12. A nonlinear filtering and predication (NFP) method for maneuvering target tracking

    Science.gov (United States)

    Chen, H.; Chang, K. C.

    2006-05-01

    A new non-linear filtering and predication (NFP) algorithm with input estimation is proposed for maneuvering target tracking. In the proposed method, the acceleration level is determined by a decision process, where a least squares (LS) estimator plays a major role to detect target maneuvering within a sliding window. In this paper, we first illustrate that the optimal solution to minimize the mean squared error (MSE) must consider a trade-off between the bias and error variance. For the application of target tracking, we then derive the MSE of target positions in a close form by using orthogonal space decompositions. Then we discuss the NFP estimator, and evaluate how well the approach potentially works in the case of given system parameters. Comparing with the traditional unbiased minimum variance filter (UMVF), Kalman filter, and interactive multiple model (IMM) algorithms, numerical results show that the newly proposed NFP method performs comparable or better in all scenarios with less computational requirements.

  13. A Novel Guidance Law with Line-of-Sight Acceleration Feedback for Missiles against Maneuvering Targets

    Directory of Open Access Journals (Sweden)

    Kemao Ma

    2014-01-01

    Full Text Available Terminal guidance law design and its implementation are considered for homing missiles against maneuvering targets. The lateral acceleration dynamics are taken into account in the design. In the guidance law design, the line-of-sight acceleration signals are incorporated into the acceleration reference signals to compensate for the targets’ maneuvers. Then the commanded accelerations are designed and the convergent tracking of the lateral accelerations to these signals is proven theoretically. In the guidance implementation, a linear high-gain differentiator is used to estimate the line-of-sight rates and the line-of-sight acceleration signals. To avoid the magnifying effects of higher order differentiation, a practical design of commanded accelerations is given to realize approximate tracking of the lateral accelerations to the given reference signals. Simulation is conducted for both cases with and without measurement noises. The simulation results justify the feasibility of the design and the implementation.

  14. Effects of Army Training Activities on Bird Communities at the Pinon Canyon Maneuver Site, Colorado

    Science.gov (United States)

    1991-09-01

    the course of the study. They are brood parasites that lay their eggs in the nests of other species, sometimes substantially reducing the nesting...of Biological Sciences, Northern Arizona University, 1979). 42. May, R.M., and SK. Robinson, "Population Dynamics of Brood Parasitism ," American...Effects of Army Training Activities on Bird Communities at the Piflon Canyon Maneuver Site, Colorado by David J. Tazik This report describes a study

  15. Designing a Fuzzy Logic Controller to Enhance Directional Stability of Vehicles under Difficult Maneuvers

    OpenAIRE

    Mehrdad N. Khajavi; Golamhassan Paygane; Ali Hakima

    2009-01-01

    Vehicle which are turning or maneuvering at high speeds are susceptible to sliding and subsequently deviate from desired path. In this paper the dynamics governing the Yaw/Roll behavior of a vehicle has been simulated. Two different simulations have been used one for the real vehicle, for which a fuzzy controller is designed to increase its directional stability property. The other simulation is for a hypothetical vehicle with much higher tire cornering stiffness which is ca...

  16. Stroke Volume during Mueller Maneuver Measured by Impedance Cardiography in Patients with Mitral Regurgitation

    Czech Academy of Sciences Publication Activity Database

    Viščor, Ivo; Jurák, Pavel; Vondra, Vlastimil; Halámek, Josef; Leinveber, Pavel

    2009-01-01

    Roč. 36, - (2009), s. 749-751 ISSN 0276-6574 R&D Projects: GA AV ČR IAA200650801; GA ČR GP102/07/P425 Institutional research plan: CEZ:AV0Z20650511 Keywords : Mueller maneuver * impedance cardiography * congestive heart failure Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering http://cinc.mit.edu/archives/2009/pdf/0749.pdf

  17. Learning, Classification and Prediction of Maneuvers of Surround Vehicles at Intersections using LSTMs

    OpenAIRE

    Khosroshahi, Aida

    2017-01-01

    Behavior analysis of vehicles surrounding the ego-vehicle is an essential component in safe and pleasant autonomous driving. This study develops a framework for activity classification of observed on-road vehicles using 3D trajectory cues and a Long Short Term Memory (LSTM) model. As a case study, we aim to classify maneuvers of surrounding vehicles at four way intersections. A variety of sensros including stereo cameras, LIDAR, GPS, and IMU measurements are used to extract ego-motion compens...

  18. Performance evaluation of control strategies for power maneuvering event of the KALIMER-600

    International Nuclear Information System (INIS)

    Seong, Seong-Hwan; Kim, Seong-O

    2012-01-01

    Highlights: ► The performance of three power control strategies of the KALIMER-600 was evaluated. ► There are turbine-, reactor- and feedwater-leading strategies in this study. ► For this, a performance analysis code was developed in this study. ► Simulation results show the turbine-leading is the best alternative. ► The feedwater-leading seems to be the second option. - Abstract: A sodium-cooled fast reactor named KALIMER-600 has been under development at KAERI. It is a pool-type reactor with the intermediate loops filled with sodium and has a superheated steam cycle with the once-through steam generators. Since the characteristic of the power control of the KALIMER-600 is expected to be different with that of a conventional power plant, the performance of the turbine-leading, reactor-leading and feedwater-leading control strategies for a power maneuvering event of the KALIMER-600 was evaluated in this study. The turbine-leading and reactor-leading strategies are very similar to those of a conventional water reactor but the feedwater-leading strategy is very similar to that of a fossil plant. Also, a performance analysis code which can analyze the plant dynamics of the KALIMER-600 and simulate the control actions during a power maneuvering event was developed. To evaluate the performance of control strategies, a simple power maneuvering event including a 10% step change and a ramp change with a rate of 5%/min was assumed and simulated. Through the simulation results, the turbine-leading strategy is proven to be very suitable for the KALIMER-600 and the feedwater-leading strategy for power maneuvering seems to be a good alternative for the power control. In further studies, various performance-related events such as the reactor power cutback, turbine runback and some transients will be evaluated and the best control strategy will be suggested.

  19. Formulation of the problem of sonic boom by a maneuvering aerofoil ...

    Indian Academy of Sciences (India)

    from the aircraft. The N-wave signature of a boom is modified to a U-wave signature in a focused boom produced by an accelerating aircraft (or more generally a maneuvering aircraft, figure 3 of [10]), ..... method of wavefront construction i.e., the line joining the tips of the rays at time t in the. (x,y)-plane starting from all ...

  20. Supine to prolonged lateral position: a novel therapeutic maneuver for posterior canal benign paroxysmal positional vertigo.

    Science.gov (United States)

    Shih, Cheng-Ping; Wang, Chih-Hung

    2013-05-01

    The treatment of posterior canal benign paroxysmal positional vertigo often involves repositioning maneuvers and exercises; however, these procedures may not be suitable for patients with limb disabilities or back disorders, or for elder patients. We sought to develop a simple therapeutic maneuver as an alternative procedure, suitable for patients with a wide range of physical ability. A simple therapeutic maneuver, supine to prolonged lateral position, was developed based on the mechanism of canalolithiasis. Its efficacy in treating posterior canal benign paroxysmal positional vertigo was evaluated in a prospective study consisting of 81 objective and 13 subjective posterior canal benign paroxysmal positional vertigo patients. A successful outcome was defined as a negative Dix-Hallpike test within 2 weeks followed by the continued absence of symptoms of vertigo or dizziness for the next 4 weeks. Seventy-two patients with objective posterior canal benign paroxysmal positional vertigo and all 13 patients with subjective posterior canal benign paroxysmal positional vertigo were successfully treated: resolution rates were 88.9 and 100 %, respectively. In the objective group, negative Dix-Hallpike tests were obtained at 1 and 2 weeks in 66.7 and 88.9 % of patients, respectively. In the subjective group, the percentages of patients free of side-dependent vertigo illusions at 1 and 2 weeks were 84.6 and 100 %, respectively. These results suggest that the supine to prolonged lateral position maneuver, which is easy to perform and generally well tolerated, could be recommended as an alternative treatment modality for patients with posterior canal benign paroxysmal positional vertigo.

  1. A model for the planning of maneuver unit and engineer asset placement

    OpenAIRE

    Craig, Dean E.

    1985-01-01

    Approved for public release; distribution is unlimited This thesis develops a prototypical model for the planning of maneuver unite and engineer obstacle placement for the Airland Research Model under development at the Naval Postgraduate School. The model utilizes a multidimensional network for the representation of terrain and presents two algorithms for combat panning. A mid-European scenario for a brigade in defense is used to contrast the model solution to combat planning problems w...

  2. Home particle repositioning maneuver to prevent the recurrence of posterior canal BPPV.

    Science.gov (United States)

    Ismail, Elshahat Ibrahem; Morgan, Ashraf Elsayed; Abdeltawwab, Mohamed Moustafa

    2018-03-08

    To check the value of home particle repositioning maneuver in the prevention of the recurrence of posterior canal benign paroxysmal positional vertigo (pc-BPPV). In this study, patients diagnosed as unilateral posterior canal BPPV were selected following an accurate evaluation using video goggle VNG system. All patients were managed by particle repositioning maneuver (PRM). Patients were instructed to do home PRM once weekly for five years. Then, they were divided into two groups (according to choice of patient to do PRM). The first group (control group) consisted of 144 patients who did not do home PRM; whereas the second group (study group) included 165 patients who performed home PRM. All patients (control & study groups) were followed up every four months for five years. The study found out that the recurrence rate of pc-BPPV in control group was 33 patients in the first year (27.2%), 11 patients in second year (9%), 5 patients in third year (4%), 3 patients in fourth year (2.5%) and 3 patients in fifth year (2.5%). The recurrence of pc-BPPV in the treated side (study group) of patients was reported as 5 patients in the first year (3.5%), 3 patients in the second year (2%), 2 patients in the third year (1.4%), 2 patients in the fourth year (1.4%), and 1 patient in the fifth year (0.7%). There was statistically significant difference between the control and the study groups regarding the recurrence rates in the first year follow up which was the highest in first four months. Home particle repositioning maneuver has the capacity to prevent the recurrence of pc-BPPV. It proved to be more successful and functional in minimizing the recurrence of the disease in the study than in the control group. Hence, home particle repositioning maneuver is highly recommended for one year at least in pc-BPPV. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. In-shoe plantar tri-axial stress profiles during maximum-effort cutting maneuvers.

    Science.gov (United States)

    Cong, Yan; Lam, Wing Kai; Cheung, Jason Tak-Man; Zhang, Ming

    2014-12-18

    Soft tissue injuries, such as anterior cruciate ligament rupture, ankle sprain and foot skin problems, frequently occur during cutting maneuvers. These injuries are often regarded as associated with abnormal joint torque and interfacial friction caused by excessive external and in-shoe shear forces. This study simultaneously investigated the dynamic in-shoe localized plantar pressure and shear stress during lateral shuffling and 45° sidestep cutting maneuvers. Tri-axial force transducers were affixed at the first and second metatarsal heads, lateral forefoot, and heel regions in the midsole of a basketball shoe. Seventeen basketball players executed both cutting maneuvers with maximum efforts. Lateral shuffling cutting had a larger mediolateral braking force than 45° sidestep cutting. This large braking force was concentrated at the first metatarsal head, as indicated by its maximum medial shear stress (312.2 ± 157.0 kPa). During propulsion phase, peak shear stress occurred at the second metatarsal head (271.3 ± 124.3 kPa). Compared with lateral shuffling cutting, 45° sidestep cutting produced larger peak propulsion shear stress (463.0 ± 272.6 kPa) but smaller peak braking shear stress (184.8 ± 181.7 kPa), of which both were found at the first metatarsal head. During both cutting maneuvers, maximum medial and posterior shear stress occurred at the first metatarsal head, whereas maximum pressure occurred at the second metatarsal head. The first and second metatarsal heads sustained relatively high pressure and shear stress and were expected to be susceptible to plantar tissue discomfort or injury. Due to different stress distribution, distinct pressure and shear cushioning mechanisms in basketball footwear might be considered over different foot regions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Comparison of abdominal muscle activity during abdominal drawing-in maneuver combined with irradiation variations

    OpenAIRE

    Hwang, Young-In; Park, Du-Jin

    2017-01-01

    Many experts have used an indirect method for enhancing strength and performance of muscles in clinical practice. The indirect method, which called an irradiation is a basic procedure of proprioceptive neuromuscular facilitation, there is little research related the effects of irradiation. This study investigated abdominal muscle activity during abdominal drawing-in maneuver (ADIM) combined with irradiation variations. The study recruited 42 healthy, young adults who were divided randomly int...

  5. Does Shoe Collar Height Influence Ankle Joint Kinematics and Kinetics in Sagittal Plane Maneuvers?

    Science.gov (United States)

    Yang, Yang; Fang, Ying; Zhang, Xini; He, Junliang; Fu, Weijie

    2017-12-01

    The Objective of the study is to investigate the effects of basketball shoes with different collar heights on ankle kinematics and kinetics and athletic performance in different sagittal plane maneuvers. Twelve participants who wore high-top and low-top basketball shoes (hereafter, HS and LS, respectively) performed a weight-bearing dorsiflexion (WB-DF) maneuver, drop jumps (DJs), and lay-up jumps (LJs). Their sagittal plane kinematics and ground reaction forces were recorded using the Vicon motion capture system and Kistler force plates simultaneously. Moreover, ankle dorsiflexion and plantarflexion angles, moment, power, stiffness, and jump height were calculated. In the WB-DF test, the peak ankle dorsiflexion angle (p = 0.041) was significantly smaller in HS than in LS. Additionally, the peak ankle plantarflexion moment (p = 0.028) and power (p = 0.022) were significantly lower in HS than in LS during LJs but not during DJs. In both jumping maneuvers, no significant differences were found in the jump height or ankle kinematics between the two shoe types. According to the WB-DF test, increasing shoe collar height can effectively reduce the ankle range of motion in the sagittal plane. Although the HS did not restrict the flexion-extension performance of the ankle joint during two jumping maneuvers, an increased shoe collar height can reduce peak ankle plantarflexion moment and peak power during the push-off phase in LJs. Therefore, a higher shoe collar height should be used to circumvent effects on the partial kinetics of the ankle joint in the sagittal plane.

  6. Evaluation of Discrimination Technologies and Classification Results Live Site Demonstration: Former Waikoloa Maneuver Area

    Science.gov (United States)

    2015-06-01

    investigated to ensure that all TOI were recovered. 15. SUBJECT TERMS MetalMapper, UX -Analyze, UXO, Former Waikoloa Maneuver Area, discrimination...were calculated for each day’s data using the footprint coverage tool in Oasis montaj’s UX -Detect tool. 3.2.3 Success Criteria This objective was...algorithm in the UX -Detect package in Oasis montaj with a threshold of 5 millivolts. The Blakely test selections were then reviewed by the processor

  7. Computations of a Maneuvering Unmanned Combat Air Vehicle Using a High-Order Overset-Grid Method

    National Research Council Canada - National Science Library

    Gordnier, Raymond E; Sherer, Scott E; Visbal, Miguel R

    2007-01-01

    Simulating the flow around a maneuvering unmanned combat air vehicle (UCAV) requires a computational method capable of modeling such complex flow features as massive separation, transition from laminar to turbulent flow...

  8. Estimation of the Maximum Angle of Sideslip for Determination of Vertical-Tail Loads in Rolling Maneuvers

    National Research Council Canada - National Science Library

    Stone, Ralph

    1952-01-01

    Recent experiences have indicated that angles of sideslip in rolling maneuvers may be critical in the design of vertical tails for current research airplanes having weight distributed mainly along the fuselage...

  9. Archaeological Sites Inventory in the Black Hills of the Pinon Canyon Maneuver Site, Las Animas County, Colorado

    National Research Council Canada - National Science Library

    Owens, Mark

    2000-01-01

    .... These tree-covered areas located adjacent to open plains, appear black on the horizon. This setting of open steppes and juxtaposed hills is found along the eastern portion of the Pinon Canyon Maneuver Site (PCMS), a U.S...

  10. Strong Tracking Spherical Simplex-Radial Cubature Kalman Filter for Maneuvering Target Tracking.

    Science.gov (United States)

    Liu, Hua; Wu, Wen

    2017-03-31

    Conventional spherical simplex-radial cubature Kalman filter (SSRCKF) for maneuvering target tracking may decline in accuracy and even diverge when a target makes abrupt state changes. To overcome this problem, a novel algorithm named strong tracking spherical simplex-radial cubature Kalman filter (STSSRCKF) is proposed in this paper. The proposed algorithm uses the spherical simplex-radial (SSR) rule to obtain a higher accuracy than cubature Kalman filter (CKF) algorithm. Meanwhile, by introducing strong tracking filter (STF) into SSRCKF and modifying the predicted states' error covariance with a time-varying fading factor, the gain matrix is adjusted on line so that the robustness of the filter and the capability of dealing with uncertainty factors is improved. In this way, the proposed algorithm has the advantages of both STF's strong robustness and SSRCKF's high accuracy. Finally, a maneuvering target tracking problem with abrupt state changes is used to test the performance of the proposed filter. Simulation results show that the STSSRCKF algorithm can get better estimation accuracy and greater robustness for maneuvering target tracking.

  11. Recruitment Maneuver in Elderly Patients with Different Peripheral Chemoreflex Sensitivity during Major Abdominal Surgery

    Directory of Open Access Journals (Sweden)

    Nikita Trembach

    2016-01-01

    Full Text Available The goal of the study was to evaluate the effect of a recruitment maneuver on respiratory biomechanics, oxygenation, and hemodynamics in patients suffering from chronic heart failure with different peripheral chemoreflex sensitivity. The study was conducted in 115 elderly patients which underwent major abdominal surgery under general/epidural surgery. Peripheral chemoreflex sensitivity (PCS was evaluated with breath-holding duration (BHD during breath-holding test. All patients were divided into two groups: group H had a high PCS (BHD = 38 seconds or less, n=49; Group M had a middle PCS (BHD more than 38 seconds, n=66. Recruitment maneuver improved oxygenation and respiratory biomechanics in all cases. However, cardiac output decreased by an average of 18%–31% in group H compared to 18%–28% in group M. SVR either remained unchanged or decreased by up to 14% of the initial value in group H, while, in group M, it had a tendency to increase, which was 24% of the initial value. So, recruitment maneuver is an effective method to improve oxygenation and biomechanical properties of the respiratory system but in patients with increased peripheral chemoreflex sensitivity it associates with the risk of hemodynamic disturbances.

  12. Effects of Mendelsohn maneuver on measures of swallowing duration post stroke.

    Science.gov (United States)

    McCullough, Gary H; Kamarunas, Erin; Mann, Giselle C; Schmidley, James W; Robbins, Joanne A; Crary, Michael A

    2012-01-01

    The purpose of this pilot study was to determine whether intensive use of the Mendelsohn maneuver in patients post stroke could alter swallow physiology when used as a rehabilitative exercise. Eighteen outpatients between 6 weeks and 22 months post stroke were enrolled in this prospective study using a crossover design to compare 2 weeks of treatment with 2 weeks of no treatment. Each participant received an initial videofluoroscopic swallow study (VFSS) and an additional VFSS at the end of each week for 1 month for a total of 5 studies. During treatment weeks, participants received 2 treatment sessions per day performing Mendelsohn maneuvers with surface electromyography for biofeedback. Measures of swallowing duration, penetration/aspiration, residue, and dysphagia severity were analyzed from VFSS to compare treatment and no-treatment weeks. Significant changes occurred for measures of the duration of superior and anterior hyoid movement after 2 weeks of treatment. Improvements were observed for duration of opening of the upper esophageal sphincter (UES), but results were not statistically significant. Measures of penetration/aspiration, residue, and dysphagia severity improved throughout the study, but no differences were observed between treatment and no-treatment weeks. Intensive use of the Mendselsohn maneuver in isolation altered duration of hyoid movement and UES opening in this exploratory study. Results can guide future research toward improved selection criteria and exploration of outcomes. Larger numbers of participants and variations in treatment duration and intensity will be necessary to determine the true clinical value of this treatment.

  13. Recruitment Maneuver in Elderly Patients with Different Peripheral Chemoreflex Sensitivity during Major Abdominal Surgery.

    Science.gov (United States)

    Trembach, Nikita; Zabolotskikh, Igor

    2016-01-01

    The goal of the study was to evaluate the effect of a recruitment maneuver on respiratory biomechanics, oxygenation, and hemodynamics in patients suffering from chronic heart failure with different peripheral chemoreflex sensitivity. The study was conducted in 115 elderly patients which underwent major abdominal surgery under general/epidural surgery. Peripheral chemoreflex sensitivity (PCS) was evaluated with breath-holding duration (BHD) during breath-holding test. All patients were divided into two groups: group H had a high PCS (BHD = 38 seconds or less, n = 49); Group M had a middle PCS (BHD more than 38 seconds, n = 66). Recruitment maneuver improved oxygenation and respiratory biomechanics in all cases. However, cardiac output decreased by an average of 18%-31% in group H compared to 18%-28% in group M. SVR either remained unchanged or decreased by up to 14% of the initial value in group H, while, in group M, it had a tendency to increase, which was 24% of the initial value. So, recruitment maneuver is an effective method to improve oxygenation and biomechanical properties of the respiratory system but in patients with increased peripheral chemoreflex sensitivity it associates with the risk of hemodynamic disturbances.

  14. Study of dynamical stability of tethered systems during space tug maneuvers

    Science.gov (United States)

    Mantellato, R.; Olivieri, L.; Lorenzini, E. C.

    2017-09-01

    The dynamics of a space tether system composed of one active spacecraft, an uncontrolled large debris (e.g., a defunct satellite), and a visco-elastic tether connecting the two bodies are investigated in this paper. The active spacecraft is assumed to be equipped with a propulsive system for carrying out a tug maneuver that forces the orbital decay of the debris. The dynamical stability and the eigenfrequencies of the tethered system under the action of the thrust are investigated with both numerical and analytical models. A more complex numerical lumped-masses model provides the reference to validate the results hailing from the simplified models. Simplified models of orbital decay, tether, and debris attitude motions were derived using the Clohessy-Wiltshire equations. The results obtained with the simplified models fit very well with those from the lumped-masses model for a wide range of initial conditions. Thanks to the analytical models two resonance conditions were found, both of them affecting the attitude dynamics of the debris, that could represent a serious issue for the safety of the tug maneuver. Also, an instability mechanism that could induce the dual mass system to rotate around its center of mass under certain conditions was identified. These findings make it possible to pinpoint the set of initial conditions of the tethered system at the beginning of the thrust event that provides a dynamically stable tug maneuver for different configurations of the system (e.g., low/high thrust, stiff/elastic tethers).

  15. Impact of cerebral cardiopulmonary resuscitation maneuvers in a general hospital: prognostic factors and outcomes

    Directory of Open Access Journals (Sweden)

    Bartholomay Eduardo

    2003-01-01

    Full Text Available OBJECTIVE: To assess survival of patients undergoing cerebral cardiopulmonary resuscitation maneuvers and to identify prognostic factors for short-term survival. METHODS: Prospective study with patients undergoing cardiopulmonary resuscitation maneuvers. RESULTS: The study included 150 patients. Spontaneous circulation was re-established in 88 (58% patients, and 42 (28% were discharged from the hospital. The necessary number of patients treated to save 1 life in 12 months was 3.4. The presence of ventricular fibrillation or tachycardia (VF/VT as the initial rhythm, shorter times of cardiopulmonary resuscitation maneuvers and cardiopulmonary arrest, and greater values of mean blood pressure (BP prior to cardiopulmonary arrest were independent variables for re-establishment of spontaneous circulation and hospital discharge. The odds ratios for hospital discharge were as follows: 6.1 (95% confidence interval [CI] = 2.7-13.6, when the initial rhythm was VF/VT; 9.4 (95% CI = 4.1-21.3, when the time of cerebral cardiopulmonary resuscitation was 70 mmHg. CONCLUSION: The presence of VF/VT as the initial rhythm, shorter times of cerebral cardiopulmonary resuscitation and of cardiopulmonary arrest, and a greater value of BP prior to cardiopulmonary arrest were independent variables of better prognosis.

  16. Prediction of Ship Unsteady Maneuvering in Calm Water by a Fully Nonlinear Ship Motion Model

    Directory of Open Access Journals (Sweden)

    Ray-Qing Lin

    2012-01-01

    Full Text Available This is the continuation of our research on development of a fully nonlinear, dynamically consistent, numerical ship motion model (DiSSEL. In this study we will report our results in predicting ship motions in unsteady maneuvering in calm water. During the unsteady maneuvering, both the rudder angle, and ship forward speed vary with time. Therefore, not only surge, sway, and yaw motions occur, but roll, pitch and heave motions will also occur even in calm water as heel, trim, and sinkage, respectively. When the rudder angles and ship forward speed vary rapidly with time, the six degrees-of-freedom ship motions and their interactions become strong. To accurately predict the six degrees-of-freedom ship motions in unsteady maneuvering, a universal method for arbitrary ship hull requires physics-based fully-nonlinear models for ship motion and for rudder forces and moments. The numerical simulations will be benchmarked by experimental data of the Pre-Contract DDG51 design and an Experimental Hull Form. The benchmarking shows a good agreement between numerical simulations by the enhancement DiSSEL and experimental data. No empirical parameterization is used, except for the influence of the propeller slipstream on the rudder, which is included using a flow acceleration factor.

  17. Autonomous Soft Robotic Fish Capable of Escape Maneuvers Using Fluidic Elastomer Actuators.

    Science.gov (United States)

    Marchese, Andrew D; Onal, Cagdas D; Rus, Daniela

    2014-03-01

    In this work we describe an autonomous soft-bodied robot that is both self-contained and capable of rapid, continuum-body motion. We detail the design, modeling, fabrication, and control of the soft fish, focusing on enabling the robot to perform rapid escape responses. The robot employs a compliant body with embedded actuators emulating the slender anatomical form of a fish. In addition, the robot has a novel fluidic actuation system that drives body motion and has all the subsystems of a traditional robot onboard: power, actuation, processing, and control. At the core of the fish's soft body is an array of fluidic elastomer actuators. We design the fish to emulate escape responses in addition to forward swimming because such maneuvers require rapid body accelerations and continuum-body motion. These maneuvers showcase the performance capabilities of this self-contained robot. The kinematics and controllability of the robot during simulated escape response maneuvers are analyzed and compared with studies on biological fish. We show that during escape responses, the soft-bodied robot has similar input-output relationships to those observed in biological fish. The major implication of this work is that we show soft robots can be both self-contained and capable of rapid body motion.

  18. Motor vehicle-bicycle crashes in Beijing: irregular maneuvers, crash patterns, and injury severity.

    Science.gov (United States)

    Yan, Xinping; Ma, Ming; Huang, Helai; Abdel-Aty, Mohamed; Wu, Chaozhong

    2011-09-01

    This research presents a comprehensive analysis of motor vehicle-bicycle crashes using 4 years of reported crash data (2004-2007) in Beijing. The interrelationship of irregular maneuvers, crash patterns and bicyclist injury severity are investigated by controlling for a variety of risk factors related to bicyclist demographics, roadway geometric design, road environment, etc. Results show that different irregular maneuvers are correlated with a number of risk factors at different roadway locations such as the bicyclist age and gender, weather and traffic condition. Furthermore, angle collisions are the leading pattern of motor vehicle-bicycle crashes, and different irregular maneuvers may lead to some specific crash patterns such as head-on or rear-end crashes. Orthokinetic scrape is more likely to result in running over bicyclists, which may lead to more severe injury. Moreover, bicyclist injury severity level could be elevated by specific crash patterns and risk factors including head-on and angle collisions, occurrence of running over bicyclists, night without streetlight, roads without median/division, higher speed limit, heavy vehicle involvement and older bicyclists. This study suggests installation of median, division between roadway and bikeway, and improvement of illumination on road segments. Reduced speed limit is also recommended at roadway locations with high bicycle traffic volume. Furthermore, it may be necessary to develop safety campaigns aimed at male, teenage and older bicyclists. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Repositioning intervals in the modified Epley's maneuver and their effect on benign paroxysmal positional vertigo treatment outcome.

    Science.gov (United States)

    Kahraman, Serif Samil; Yildirim, Yavuz Selim; Tugrul, Selhattin; Ozturan, Orhan

    2017-05-01

    This study showed that short and long interval treatments achieved comparable success rates. There was no statistically significant difference in the rate of early and late recurrences between the two groups. Modified Epley maneuver can be applied in a short interval time with comparable success and recurrence rates which are as effective as in a long interval time. The Epley maneuver is called the particle repositioning or canalith repositioning procedure. If a short time interval in each position is effective, it will allow for reduced time and avoid unnecessary physical burden. How long of a stay in each position is not determined in the literature. There is an absence of comparative studies of the BPPV repositioning time. The aim of this study is to compare the treatment time in patients with benign paroxysmal positional vertigo (BPPV). Longitudinal prospective study. Outpatient practice in a tertiary care facility. Sixty consecutive patients with BPPV were included in this study. These patients were sequentially allocated to one of two groups (A or B). The interval times between each position in group A and B were 15 and 120 s, respectively. Modified Epley maneuver was performed in all patients. The maneuvers in both groups were exactly the same sequence of movements, except interval times. The mean age of the patients was 49.25 years (range =19-76 years). Of the 60 patients, 48 (80%) were women and 12 (20%) were men. Successful outcome was achieved in 26 patients (86.7%) after the first modified Epley maneuver in both groups. Three patients from each group (total six patients) responded to the third modified Epley maneuver and the remaining two patients did not respond to any modified Epley maneuver. Therefore, the Semont maneuver was applied with a successful result.

  20. A randomised clinical trial on cardiotocography plus fetal blood sampling versus cardiotocography plus ST-analysis of the fetal electrocardiogram (STAN® for intrapartum monitoring

    Directory of Open Access Journals (Sweden)

    Rijnders Robbert JP

    2007-07-01

    . Assuming a reduction of metabolic acidosis from 3.5% to 2.1 %, using a two-sided test with an alpha of 0.05 and a power of 0.80, in favour of CTG plus ST-analysis, about 5100 women have to be randomised. Furthermore, the cost-effectiveness of CTG and ST-analysis as compared to CTG and FBS will be studied. Discussion This study will provide data about the use of intrapartum ST-analysis with a strict protocol for performance of FBS to limit its incidence. We aim to clarify to what extent intrapartum ST-analysis can be used without the performance of FBS and in which cases FBS is still needed. Trial Registration Number ISRCTN95732366

  1. Maintaining Aura's Orbit Requirements While Performing Orbit Maintenance Maneuvers Containing an Orbit Normal Delta-V Component

    Science.gov (United States)

    Johnson, Megan R.; Petersen, Jeremy D.

    2014-01-01

    The Earth Observing System (EOS) Afternoon Constellation consists of five member missions (GCOM-W1, Aqua, CALIPSO, CloudSat, and Aura), each of which maintain a frozen, sun-synchronous orbit with a 16-day repeating ground track that follows the Worldwide Reference System-2 (WRS-2). Under nominal science operations for Aura, the propulsion system is oriented such that the resultant thrust vector is aligned 13.493 degrees away from the velocity vector along the yaw axis. When performing orbit maintenance maneuvers, the spacecraft performs a yaw slew to align the thrust vector in the appropriate direction. A new Drag Make Up (DMU) maneuver operations scheme has been implemented for Aura alleviating the need for the 13.493 degree yaw slew. The focus of this investigation is to assess the impact that no-slew DMU maneuver operations will have on Aura's Mean Local Time (MLT) which drives the required along track separation between Aura and the constellation members, as well as Aura's frozen orbit properties, eccentricity and argument of perigee. Seven maneuver strategies were analyzed to determine the best operational approach. A mirror pole strategy, with maneuvers alternating at the North and South poles, was implemented operationally to minimize impact to the MLT. Additional analysis determined that the mirror pole strategy could be further modified to include frozen orbit maneuvers and thus maintain both MLT and the frozen orbit properties under noslew operations.

  2. Evaluation of pelvic floor muscles activity with and without abdominal maneuvers in subjects with and without low back pain.

    Science.gov (United States)

    Ehsani, Fatemeh; Arab, Amir Massoud; Assadi, Hamed; Karimi, Noureddin; Shanbehzadeh, Sanaz

    2016-04-27

    There was controversy in finding of studies related pelvic floor muscle (PFM) rehabilitation of subjects with low back pain (LBP), while this issue is very important for treatment of subjects with LBP. The purpose of this study was to evaluate PFM contraction in three conditions of alone and with abdominal hollowing (AH) or abdominal bracing (AB) maneuvers in subjects with and without chronic LBP. Subjects were divided into two groups: subjects with LBP (N = 25) and without LBP (N = 27). PFM contraction alone and during contraction with AH or AB maneuvers was measured. The amount of bladder base movement was measured as an indicator of PFM activity. There were no differences in PFM activity between subjects with and without chronic LBP, when PFM contracted alone (P = 0.60), contracted with AH (P= 0.12) and AB maneuver (P = 0.54). Our data revealed that contraction of the PFM alone produce greater displacement of the bladder base than contraction of the PFM with AH (P = 0.005) or AB maneuver (P = 0.001) in both groups. However, no significant difference was found between contraction of the PFM with AH and AB maneuver in individuals with LBP (P = 0.31). It seems that PFM contraction alone is more effective than PFM contraction with AH or AB maneuvers in lifting the pelvic floor in subjects with and without LBP.

  3. Disrespectful intrapartum care during facility-based delivery in sub-Saharan Africa: A qualitative systematic review and thematic synthesis of women's perceptions and experiences.

    Science.gov (United States)

    Bradley, Susan; McCourt, Christine; Rayment, Juliet; Parmar, Divya

    2016-11-01

    The psycho-social elements of labour and delivery are central to any woman's birth experience, but international efforts to reduce maternal mortality in low-income contexts have neglected these aspects and focused on technological birth. In many contexts, maternity care is seen as dehumanised and disrespectful, which can have a negative impact on utilisation of services. We undertook a systematic review and meta-synthesis of the growing literature on women's experiences of facility-based delivery in sub-Saharan Africa to examine the drivers of disrespectful intrapartum care. Using PRISMA guidelines, databases were searched from 1990 to 06 May 2015, and 25 original studies were included for thematic synthesis. Analytical themes, that were theoretically informed and cognisant of the cultural and social context in which the dynamics of disrespectful care occur, enabled a fresh interpretation of the factors driving midwives' behaviour. A conceptual framework was developed to show how macro-, meso- and micro-level drivers of disrespectful care interact. The synthesis revealed a prevailing model of maternity care that is institution-centred, rather than woman-centred. Women's experiences illuminate midwives' efforts to maintain power and control by situating birth as a medical event and to secure status by focusing on the technical elements of care, including controlling bodies and knowledge. Midwives and women are caught between medical and social models of birth. Global policies encouraging facility-based delivery are forcing women to swap the psycho-emotional care they would receive from traditional midwives for the technical care that professional midwives are currently offering. Any action to change the current performance and dynamic of birth relies on the participation of midwives, but their voices are largely missing from the discourse. Future research should explore their perceptions of the value and practice of interpersonal aspects of maternity care and the

  4. A multicenter randomized double-blind study: comparison of the Epley, Semont, and sham maneuvers for the treatment of posterior canal benign paroxysmal positional vertigo.

    Science.gov (United States)

    Lee, Jong Dae; Shim, Dae Bo; Park, Hong Ju; Song, Chan Il; Kim, Min-Beom; Kim, Chang-Hee; Byun, Jae Yong; Hong, Sung Kwang; Kim, Tae Su; Park, Kye Hoon; Seo, Jae-Hyun; Shim, Byoung Soo; Lee, Joon Han; Lim, Hyun Woo; Jeon, Eun-Ju

    2014-01-01

    We evaluated the short-term efficacy of Epley, Semont, and sham maneuvers for resolving posterior canal benign paroxysmal positional vertigo (BPPV) in a prospective multicenter randomized double-blind controlled study. Subjects were randomly divided into three groups: Epley (36 patients), Semont (32 patients), and sham (Epley maneuver for the unaffected side, 31 patients). Out of 14 institutes which participated in this study, 5 institutes had previous experience of the Epley but not the Semont maneuver and the other 9 had previous experience of both maneuvers. Each maneuver was repeated twice if there was still positional vertigo or nystagmus on day 0, and the presence of nystagmus and vertigo on positional testing were evaluated immediately, 1 day, and 1 week after treatment. After the first maneuver, the Epley group showed a significantly higher resolution rate of positional nystagmus than the Semont or sham groups (63.9, 37.5, and 38.7%, respectively). After the second maneuver, the resolution rate (83.3%) of the Epley group was significantly higher than that (51.6%) of the sham group. At 1 day and 1 week after treatment, the resolution rate of the Epley group was significantly higher than those of the other groups. Similar results were seen for the resolution of positional vertigo. The Epley maneuver showed persistent resolution rates of positional vertigo and nystagmus without a fatigue phenomenon. The Epley maneuver was significantly more effective per maneuver than Semont or sham maneuvers for the short-term treatment of posterior canal BPPV. The Semont maneuver showed a higher success rate than the sham maneuver, but it was not significantly different. © 2014 S. Karger AG, Basel.

  5. Effectiveness of Otolith Repositioning Maneuvers and Vestibular Rehabilitation exercises in elderly people with Benign Paroxysmal Positional Vertigo: a systematic review

    Directory of Open Access Journals (Sweden)

    Karyna Figueiredo Ribeiro

    Full Text Available Abstract Introduction Benign Paroxysmal Positional Vertigo is highly prevalent in elderly people. This condition is related to vertigo, hearing loss, tinnitus, poor balance, gait disturbance, and an increase in risk of falls, leading to postural changes and quality of life decreasing. Objective To evaluate the outcomes obtained by clinical trials on the effectiveness of Otolith Repositioning Maneuver and Vestibular Rehabilitation exercises in the treatment of Benign Paroxysmal Positional Vertigo in elderly. Methods The literature research was performed using PubMed, Scopus, Web of Science and PEDro databases, and included randomized controlled clinical trials in English, Spanish and Portuguese, published during January 2000 to August 2016. The methodological quality of the studies was assessed by PEDro score and the outcomes analysis was done by critical revision of content. Results Six studies were fully reviewed. The average age of participants ranged between 67.2 and 74.5 years. The articles were classified from 2 to 7/10 through the PEDro score. The main outcome measures analyzed were vertigo, positional nystagmus and postural balance. Additionally, the number of maneuvers necessary for remission of the symptoms, the quality of life, and the functionality were also assessed. The majority of the clinical trials used Otolith Repositioning Maneuver (n = 5 and 3 articles performed Vestibular Rehabilitation exercises in addition to Otolith Repositioning Maneuver or pharmacotherapy. One study showed that the addition of movement restrictions after maneuver did not influence the outcomes. Conclusion There was a trend of improvement in Benign Paroxysmal Positional Vertigo symptomatology in elderly patients who underwent Otolith Repositioning Maneuver. There is sparse evidence from methodologically robust clinical trials that examined the effects of Otolith Repositioning Maneuver and Vestibular Rehabilitation exercises for treating Benign Paroxysmal

  6. Effectiveness of Otolith Repositioning Maneuvers and Vestibular Rehabilitation exercises in elderly people with Benign Paroxysmal Positional Vertigo: a systematic review.

    Science.gov (United States)

    Ribeiro, Karyna Figueiredo; Oliveira, Bruna Steffeni; Freitas, Raysa V; Ferreira, Lidiane M; Deshpande, Nandini; Guerra, Ricardo O

    2017-06-29

    Benign Paroxysmal Positional Vertigo is highly prevalent in elderly people. This condition is related to vertigo, hearing loss, tinnitus, poor balance, gait disturbance, and an increase in risk of falls, leading to postural changes and quality of life decreasing. To evaluate the outcomes obtained by clinical trials on the effectiveness of Otolith Repositioning Maneuver and Vestibular Rehabilitation exercises in the treatment of Benign Paroxysmal Positional Vertigo in elderly. The literature research was performed using PubMed, Scopus, Web of Science and PEDro databases, and included randomized controlled clinical trials in English, Spanish and Portuguese, published during January 2000 to August 2016. The methodological quality of the studies was assessed by PEDro score and the outcomes analysis was done by critical revision of content. Six studies were fully reviewed. The average age of participants ranged between 67.2 and 74.5 years. The articles were classified from 2 to 7/10 through the PEDro score. The main outcome measures analyzed were vertigo, positional nystagmus and postural balance. Additionally, the number of maneuvers necessary for remission of the symptoms, the quality of life, and the functionality were also assessed. The majority of the clinical trials used Otolith Repositioning Maneuver (n=5) and 3 articles performed Vestibular Rehabilitation exercises in addition to Otolith Repositioning Maneuver or pharmacotherapy. One study showed that the addition of movement restrictions after maneuver did not influence the outcomes. There was a trend of improvement in Benign Paroxysmal Positional Vertigo symptomatology in elderly patients who underwent Otolith Repositioning Maneuver. There is sparse evidence from methodologically robust clinical trials that examined the effects of Otolith Repositioning Maneuver and Vestibular Rehabilitation exercises for treating Benign Paroxysmal Positional Vertigo in the elderly. Randomized controlled clinical trials with

  7. Uncertainty Requirement Analysis for the Orbit, Attitude, and Burn Performance of the 1st Lunar Orbit Insertion Maneuver

    Directory of Open Access Journals (Sweden)

    Young-Joo Song

    2016-12-01

    Full Text Available In this study, the uncertainty requirements for orbit, attitude, and burn performance were estimated and analyzed for the execution of the 1st lunar orbit insertion (LOI maneuver of the Korea Pathfinder Lunar Orbiter (KPLO mission. During the early design phase of the system, associate analysis is an essential design factor as the 1st LOI maneuver is the largest burn that utilizes the onboard propulsion system; the success of the lunar capture is directly affected by the performance achieved. For the analysis, the spacecraft is assumed to have already approached the periselene with a hyperbolic arrival trajectory around the moon. In addition, diverse arrival conditions and mission constraints were considered, such as varying periselene approach velocity, altitude, and orbital period of the capture orbit after execution of the 1st LOI maneuver. The current analysis assumed an impulsive LOI maneuver, and two-body equations of motion were adapted to simplify the problem for a preliminary analysis. Monte Carlo simulations were performed for the statistical analysis to analyze diverse uncertainties that might arise at the moment when the maneuver is executed. As a result, three major requirements were analyzed and estimated for the early design phase. First, the minimum requirements were estimated for the burn performance to be captured around the moon. Second, the requirements for orbit, attitude, and maneuver burn performances were simultaneously estimated and analyzed to maintain the 1st elliptical orbit achieved around the moon within the specified orbital period. Finally, the dispersion requirements on the B-plane aiming at target points to meet the target insertion goal were analyzed and can be utilized as reference target guidelines for a mid-course correction (MCC maneuver during the transfer. More detailed system requirements for the KPLO mission, particularly for the spacecraft bus itself and for the flight dynamics subsystem at the ground

  8. Analysis of Driver Evasive Maneuvering Prior to Intersection Crashes Using Event Data Recorders.

    Science.gov (United States)

    Scanlon, John M; Kusano, Kristofer D; Gabler, Hampton C

    2015-01-01

    Intersection crashes account for over 4,500 fatalities in the United States each year. Intersection Advanced Driver Assistance Systems (I-ADAS) are emerging vehicle-based active safety systems that have the potential to help drivers safely navigate across intersections and prevent intersection crashes and injuries. The performance of an I-ADAS is expected to be highly dependent upon driver evasive maneuvering prior to an intersection crash. Little has been published, however, on the detailed evasive kinematics followed by drivers prior to real-world intersection crashes. The objective of this study was to characterize the frequency, timing, and kinematics of driver evasive maneuvers prior to intersection crashes. Event data recorders (EDRs) downloaded from vehicles involved in intersection crashes were investigated as part of NASS-CDS years 2001 to 2013. A total of 135 EDRs with precrash vehicle speed and braking application were downloaded to investigate evasive braking. A smaller subset of 59 EDRs that collected vehicle yaw rate was additionally analyzed to investigate evasive steering. Each vehicle was assigned to one of 3 precrash movement classifiers (traveling through the intersection, completely stopped, or rolling stop) based on the vehicle's calculated acceleration and observed velocity profile. To ensure that any significant steering input observed was an attempted evasive maneuver, the analysis excluded vehicles at intersections that were turning, driving on a curved road, or performing a lane change. Braking application at the last EDR-recorded time point was assumed to indicate evasive braking. A vehicle yaw rate greater than 4° per second was assumed to indicate an evasive steering maneuver. Drivers executed crash avoidance maneuvers in four-fifths of intersection crashes. A more detailed analysis of evasive braking frequency by precrash maneuver revealed that drivers performing complete or rolling stops (61.3%) braked less often than drivers

  9. Immediate effects of breath holding maneuvers onto composition of exhaled breath.

    Science.gov (United States)

    Sukul, Pritam; Trefz, Phillip; Schubert, Jochen K; Miekisch, Wolfram

    2014-09-01

    Rapid concentration changes due to physiological or pathophysiological effects rather than appearance of unique disease biomarkers are important for clinical application of breath research. Simple maneuvers such as breath holding may significantly affect breath biomarker concentrations. In this study, exhaled volatile organic compound (VOC) concentrations were assessed in real time before and after different breath holding maneuvers. Continuous breath-resolved measurements (PTR-ToF-MS-8000) were performed in 31 healthy human subjects in a side-stream sampling mode. After 1 min of tidal breathing participants held their breath for 10, 20, 40, 60 s and as long as possible. Afterwards they continued to breathe normally for another minute. VOC profiles could be monitored in real time by assigning online PTR-ToF-MS data to alveolar or inspired phases of breath. Sudden and profound changes of exhaled VOC concentrations were recorded after different breath holding maneuvers. VOC concentrations returned to base line levels 10-20 s after breath holding. Breath holding induced concentration changes depended on physico-chemical properties of the substances. When substance concentrations were normalized onto end-tidal CO2 content, variation of acetone concentrations decreased, whereas variations of isoprene concentrations were not affected. As the effects of breathing patterns on exhaled substance concentrations depend on individual substance properties, sampling procedures have to be validated for each compound by means of appropriate real-time analysis. Normalization of exhaled concentrations onto exhaled CO2 is only valid for substances having similar physico-chemical properties as CO2.

  10. How Lovebirds Maneuver Rapidly Using Super-Fast Head Saccades and Image Feature Stabilization

    Science.gov (United States)

    Kress, Daniel; van Bokhorst, Evelien; Lentink, David

    2015-01-01

    Diurnal flying animals such as birds depend primarily on vision to coordinate their flight path during goal-directed flight tasks. To extract the spatial structure of the surrounding environment, birds are thought to use retinal image motion (optical flow) that is primarily induced by motion of their head. It is unclear what gaze behaviors birds perform to support visuomotor control during rapid maneuvering flight in which they continuously switch between flight modes. To analyze this, we measured the gaze behavior of rapidly turning lovebirds in a goal-directed task: take-off and fly away from a perch, turn on a dime, and fly back and land on the same perch. High-speed flight recordings revealed that rapidly turning lovebirds perform a remarkable stereotypical gaze behavior with peak saccadic head turns up to 2700 degrees per second, as fast as insects, enabled by fast neck muscles. In between saccades, gaze orientation is held constant. By comparing saccade and wingbeat phase, we find that these super-fast saccades are coordinated with the downstroke when the lateral visual field is occluded by the wings. Lovebirds thus maximize visual perception by overlying behaviors that impair vision, which helps coordinate maneuvers. Before the turn, lovebirds keep a high contrast edge in their visual midline. Similarly, before landing, the lovebirds stabilize the center of the perch in their visual midline. The perch on which the birds land swings, like a branch in the wind, and we find that retinal size of the perch is the most parsimonious visual cue to initiate landing. Our observations show that rapidly maneuvering birds use precisely timed stereotypic gaze behaviors consisting of rapid head turns and frontal feature stabilization, which facilitates optical flow based flight control. Similar gaze behaviors have been reported for visually navigating humans. This finding can inspire more effective vision-based autopilots for drones. PMID:26107413

  11. A Flight Training Simulator for Instructing the Helicopter Autorotation Maneuver (Enhanced Version)

    Science.gov (United States)

    Rogers, Steven P.; Asbury, Charles N.

    2000-01-01

    Autorotation is a maneuver that permits a safe helicopter landing when the engine loses power. A catastrophe may occur if the pilot's control inputs are incorrect, insufficient, excessive, or poorly timed. Due to the danger involved, full-touchdown autorotations are very rarely practiced. Because in-flight autorotation training is risky, time-consuming, and expensive, the objective of the project was to develop the first helicopter flight simulator expressly designed to train students in this critical maneuver. A central feature of the project was the inclusion of an enhanced version of the Pilot-Rotorcraft Intelligent Symbology Management Simulator (PRISMS), a virtual-reality system developed by Anacapa Sciences and Thought Wave. A task analysis was performed to identify the procedural steps in the autorotation, to inventory the information needed to support student task performance, to identify typical errors, and to structure the simulator's practice environment. The system provides immediate knowledge of results, extensive practice of perceptual-motor skills, part-task training, and augmented cueing in a realistic cockpit environment. Additional work, described in this report, extended the capabilities of the simulator in three areas: 1. Incorporation of visual training aids to assist the student in learning the proper appearance of the visual scene when the maneuver is being properly performed; 2. Introduction of the requirement to land at a particular spot, as opposed to the wide, flat open field initially used, and development of appropriate metrics of success; and 3. Inclusion of wind speed and wind direction settings (and random variability settings) to add a more realistic challenge in "hitting the spot."

  12. The Low Mandible Maneuver and Its Resonential Implications for Elite Singers.

    Science.gov (United States)

    Nair, Angelika; Nair, Garyth; Reishofer, Gernot

    2016-01-01

    Many elite singers appear to frequently drop the posterior mandible while singing to optimize resonance production. This study investigated the physiology of the Low Mandible Maneuver (LMM) through the use of magnetic resonance imaging (MRI), ultrasound (US), and spectrographic analysis. The study of elite singers has been hampered by the paucity of internal imagery. We have attempted to address this problem by using portable US equipment that we could transport to the homes, studios, or dressing rooms of such ranking singers. With the US and acoustic data gathered in fairly brief sessions, we were able to ascertain the resonance gains garnered from the technique's use. The study featured two phases: I--MRI study of the maneuver and its physiological effect on surrounding structures (in collaboration of the Medical University of Graz, Austria) and II--US investigation that studied tongue shape during the maneuver. The LMM has significant ramifications for resonance production by enabling a concomitantly lowered larynx and increased resonance space in the pharyngeal and oral cavities. Measurements of the LMM ranged between 0.7 and 3.1 cm and showed a boost in the first harmonics as well as an enhancement in the singers formant. Its use also has a rather significant effect on the tongue shapes required for all sung phonemes. The advantage of using US for this study was the ability to produce real-time videos of the singer in action and then, through the use of stop action, precisely study both individual phoneme production and phoneme-to-phoneme transitions during the LMM. Copyright © 2016 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  13. Driver behavior during bicycle passing maneuvers in response to a Share the Road sign treatment.

    Science.gov (United States)

    Kay, Jonathan J; Savolainen, Peter T; Gates, Timothy J; Datta, Tapan K

    2014-09-01

    The interaction of motorists and bicyclists, particularly during passing maneuvers, is an area of concern to the bicycle safety community as there is a general perception that motor vehicle drivers may not share the road effectively with bicyclists. This is a particular concern on road sections with centerline rumble strips where motorists are prone to crowd bicyclists during passing events. One potential countermeasure to address this concern is the use of a bicycle warning sign with a "Share the Road" plaque. This paper presents the results of a controlled field evaluation of this sign treatment, which involved an examination of driver behavior while overtaking bicyclists. A series of field studies were conducted concurrently on two segments of a high-speed, rural two-lane highway. These segments were similar in terms of roadway geometry, traffic volumes, and other relevant factors, except that one of the segments included centerline rumble strips while the other did not. A before-and-after study design was utilized to examine changes in motor vehicle lateral placement and speed at the time of the passing event as they relate to the presence of centerline rumble strips and the sign treatment. Centerline rumble strips generally shifted vehicles closer to the bicyclists during passing maneuvers, though the magnitude of this effect was marginal. The sign treatment was found to shift motor vehicles away from the rightmost lane positions, though the signs did not significantly affect the mean buffer distance between the bicyclists and passing motorists or the propensity of crowding events during passing. The sign treatment also resulted in a 2.5miles/h (4.0km/h) reduction in vehicle speeds. Vehicle type, bicyclist position, and the presence of opposing traffic were also found to affect lateral placement and speed selection during passing maneuvers. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. A fast assistant decision-making system on the emergent maneuver of the tracking ship

    Science.gov (United States)

    Huang, Qiong; Xue, G. H.; Ni, X. Q.

    2016-02-01

    This paper studies a fast assistant decision-making system on the emergent maneuver of the tracking ship, adopting the design method of the emergent working state of the tracking ship based on the meteorological prediction, the virtual display technology based on the multi-stage mapping, and the 2-dimension area algorithm based on the line-scanning. It solves problems that the tracking ship met during working, such as the long TT&C time, the dense crucial observation arc, the complicated working flow, and the changeful scheme. It established the hard basement for the fast design of the emergency working state when the tracking ship in the awful sea conditions.

  15. Modelling the EDLC-based Power Supply Module for a Maneuvering System of a Nanosatellite

    Science.gov (United States)

    Kumarin, A. A.; Kudryavtsev, I. A.

    2018-01-01

    The development of the model of the power supply module of a maneuvering system of a nanosatellite is described. The module is based on an EDLC battery as an energy buffer. The EDLC choice is described. Experiments are conducted to provide data for model. Simulation of the power supply module is made for charging and discharging of the battery processes. The difference between simulation and experiment does not exceed 0.5% for charging and 10% for discharging. The developed model can be used in early design and to adjust charger and load parameters. The model can be expanded to represent the entire power system.

  16. Driver Behavior During Overtaking Maneuvers from the 100-Car Naturalistic Driving Study.

    Science.gov (United States)

    Chen, Rong; Kusano, Kristofer D; Gabler, Hampton C

    2015-01-01

    Lane changes with the intention to overtake the vehicle in front are especially challenging scenarios for forward collision warning (FCW) designs. These overtaking maneuvers can occur at high relative vehicle speeds and often involve no brake and/or turn signal application. Therefore, overtaking presents the potential of erroneously triggering the FCW. A better understanding of driver behavior during lane change events can improve designs of this human-machine interface and increase driver acceptance of FCW. The objective of this study was to aid FCW design by characterizing driver behavior during lane change events using naturalistic driving study data. The analysis was based on data from the 100-Car Naturalistic Driving Study, collected by the Virginia Tech Transportation Institute. The 100-Car study contains approximately 1.2 million vehicle miles of driving and 43,000 h of data collected from 108 primary drivers. In order to identify overtaking maneuvers from a large sample of driving data, an algorithm to automatically identify overtaking events was developed. The lead vehicle and minimum time to collision (TTC) at the start of lane change events was identified using radar processing techniques developed in a previous study. The lane change identification algorithm was validated against video analysis, which manually identified 1,425 lane change events from approximately 126 full trips. Forty-five drivers with valid time series data were selected from the 100-Car study. From the sample of drivers, our algorithm identified 326,238 lane change events. A total of 90,639 lane change events were found to involve a closing lead vehicle. Lane change events were evenly distributed between left side and right side lane changes. The characterization of lane change frequency and minimum TTC was divided into 10 mph speed bins for vehicle travel speeds between 10 and 90 mph. For all lane change events with a closing lead vehicle, the results showed that drivers change

  17. Mission Capability Gains from Multi-Mode Propulsion Thrust Variations on a Variety Spacecraft Orbital Maneuvers

    Science.gov (United States)

    2011-03-01

    a 30 cm derated ion thruster, a xenon Hall thruster (SPT-100), and a hydrazine arcjet thruster. Repositioning a spacecraft in a sun synchronous low ...4000, which has a high thrust/high power mode and a low thrust/ low power mode. The maximum thrust on this system was around 0.3 N and has had...Small Satellite LEO Maneuvers with Low - Power Electric Propulsion,” 44th AIAA/ASME/SAE/ASEE Joint Propulsion Conference, AIAA 2008-4516.     99

  18. Advanced fighter technology integration (AFTI)/F-16 Automated Maneuvering Attack System final flight test results

    Science.gov (United States)

    Dowden, Donald J.; Bessette, Denis E.

    1987-01-01

    The AFTI F-16 Automated Maneuvering Attack System has undergone developmental and demonstration flight testing over a total of 347.3 flying hours in 237 sorties. The emphasis of this phase of the flight test program was on the development of automated guidance and control systems for air-to-air and air-to-ground weapons delivery, using a digital flight control system, dual avionics multiplex buses, an advanced FLIR sensor with laser ranger, integrated flight/fire-control software, advanced cockpit display and controls, and modified core Multinational Stage Improvement Program avionics.

  19. Space shuttle maneuvering engine reusable thrust chamber program. Task 11: Low Epsilon stability test plan

    Science.gov (United States)

    Pauckert, R. P.

    1974-01-01

    The performance and heat transfer characteristics of a doublet element type injector for the space shuttle orbiter maneuvering engine thrust chamber were investigated. Ths stability characteristics were evaluated over a range of chamber pressures and mixture ratios. The specific objectives of the test were: (1) to determine whether stability has been influenced by injection of boundary layer coolant across the cavity entrance, (2) if the injector is stable, to determine the minimum cavity area required to maintain stability, and (3) if the injector is unstable, to determine the effects of entrance geometry and increased area on stability.

  20. An Adaptive Nonlinear Aircraft Maneuvering Envelope Estimation Approach for Online Applications

    Science.gov (United States)

    Schuet, Stefan R.; Lombaerts, Thomas Jan; Acosta, Diana; Wheeler, Kevin; Kaneshige, John

    2014-01-01

    A nonlinear aircraft model is presented and used to develop an overall unified robust and adaptive approach to passive trim and maneuverability envelope estimation with uncertainty quantification. The concept of time scale separation makes this method suitable for the online characterization of altered safe maneuvering limitations after impairment. The results can be used to provide pilot feedback and/or be combined with flight planning, trajectory generation, and guidance algorithms to help maintain safe aircraft operations in both nominal and off-nominal scenarios.

  1. Dynamics and Control of Three-Dimensional Perching Maneuver under Dynamic Stall Influence

    Science.gov (United States)

    Feroskhan, Mir Alikhan Bin Mohammad

    Perching is a type of aggressive maneuver performed by the class 'Aves' species to attain precision point landing with a generally short landing distance. Perching capability is desirable on unmanned aerial vehicles (UAVs) due to its efficient deceleration process that potentially expands the functionality and flight envelope of the aircraft. This dissertation extends the previous works on perching, which is mostly limited to two-dimensional (2D) cases, to its state-of-the-art threedimensional (3D) variety. This dissertation presents the aerodynamic modeling and optimization framework adopted to generate unprecedented variants of the 3D perching maneuver that include the sideslip perching trajectory, which ameliorates the existing 2D perching concept by eliminating the undesirable undershoot and reliance on gravity. The sideslip perching technique methodically utilizes the lateral and longitudinal drag mechanisms through consecutive phases of yawing and pitching-up motion. Since perching maneuver involves high rates of change in the angles of attack and large turn rates, introduction of three internal variables thus becomes necessary for addressing the influence of dynamic stall delay on the UAV's transient post-stall behavior. These variables are then integrated into a static nonlinear aerodynamic model, developed using empirical and analytical methods, and into an optimization framework that generates a trajectory of sideslip perching maneuver, acquiring over 70% velocity reduction. An impact study of the dynamic stall influence on the optimal perching trajectories suggests that consideration of dynamic stall delay is essential due to the significant discrepancies in the corresponding control inputs required. A comparative study between 2D and 3D perching is also conducted to examine the different drag mechanisms employed by 2D and 3D perching respectively. 3D perching is presented as a more efficient deceleration technique with respect to spatial costs and

  2. Nonlinear Aerodynamic Modeling From Flight Data Using Advanced Piloted Maneuvers and Fuzzy Logic

    Science.gov (United States)

    Brandon, Jay M.; Morelli, Eugene A.

    2012-01-01

    Results of the Aeronautics Research Mission Directorate Seedling Project Phase I research project entitled "Nonlinear Aerodynamics Modeling using Fuzzy Logic" are presented. Efficient and rapid flight test capabilities were developed for estimating highly nonlinear models of airplane aerodynamics over a large flight envelope. Results showed that the flight maneuvers developed, used in conjunction with the fuzzy-logic system identification algorithms, produced very good model fits of the data, with no model structure inputs required, for flight conditions ranging from cruise to departure and spin conditions.

  3. A Patient-Invented Maneuver to Alleviate Freezing of Gait Using a Foot Loop Band

    Directory of Open Access Journals (Sweden)

    Yasuyuki Okuma

    2014-11-01

    Full Text Available Freezing of gait (FOG is a disabling gait disorder in parkinsonian patients characterized by the inability to initiate or continue locomotion. I herein present a 65-year-old man with Parkinson's disease who invented a unique method (foot loop band to alleviate FOG, which has not been previously described in the literature. The mechanisms to alleviate FOG include not only facilitating mechanical weight shift, but also restoring internal cueing and driving motor commands for gait initiation. This patient-invented maneuver may be recommended for patients having intractable FOG, because it is portable, cheap and safe.

  4. Satellite formation flying relative dynamics, formation design, fuel optimal maneuvers and formation maintenance

    CERN Document Server

    Wang, Danwei; Poh, Eng Kee

    2017-01-01

    This book systematically describes the concepts and principles for multi-satellite relative motion, passive and near passive formation designs, trajectory planning and control for fuel optimal formation maneuvers, and formation flying maintenance control design. As such, it provides a sound foundation for researchers and engineers in this field to develop further theories and pursue their implementations. Though satellite formation flying is widely considered to be a major advance in space technology, there are few systematic treatments of the topic in the literature. Addressing that gap, the book offers a valuable resource for academics, researchers, postgraduate students and practitioners in the field of satellite science and engineering.

  5. Exploration of the Trade Space Between Unmanned Aircraft Systems Descent Maneuver Performance and Sense-and-Avoid System Performance Requirements

    Science.gov (United States)

    Jack, Devin P.; Hoffler, Keith D.; Johnson, Sally C.

    2014-01-01

    A need exists to safely integrate Unmanned Aircraft Systems (UAS) into the United States' National Airspace System. Replacing manned aircraft's see-and-avoid capability in the absence of an onboard pilot is one of the key challenges associated with safe integration. Sense-and-avoid (SAA) systems will have to achieve yet-to-be-determined required separation distances for a wide range of encounters. They will also need to account for the maneuver performance of the UAS they are paired with. The work described in this paper is aimed at developing an understanding of the trade space between UAS maneuver performance and SAA system performance requirements, focusing on a descent avoidance maneuver. An assessment of current manned and unmanned aircraft performance was used to establish potential UAS performance test matrix bounds. Then, near-term UAS integration work was used to narrow down the scope. A simulator was developed with sufficient fidelity to assess SAA system performance requirements. The simulator generates closest-point-of-approach (CPA) data from the wide range of UAS performance models maneuvering against a single intruder with various encounter geometries. Initial attempts to model the results made it clear that developing maneuver performance groups is required. Discussion of the performance groups developed and how to know in which group an aircraft belongs for a given flight condition and encounter is included. The groups are airplane, flight condition, and encounter specific, rather than airplane-only specific. Results and methodology for developing UAS maneuver performance requirements are presented for a descent avoidance maneuver. Results for the descent maneuver indicate that a minimum specific excess power magnitude can assure a minimum CPA for a given time-to-go prediction. However, smaller amounts of specific excess power may achieve or exceed the same CPA if the UAS has sufficient speed to trade for altitude. The results of this study will

  6. Promising adoption of an electronic clinical decision support system for antenatal and intrapartum care in rural primary healthcare facilities in sub-Saharan Africa: The QUALMAT experience.

    Science.gov (United States)

    Sukums, Felix; Mensah, Nathan; Mpembeni, Rose; Massawe, Siriel; Duysburgh, Els; Williams, Afua; Kaltschmidt, Jens; Loukanova, Svetla; Haefeli, Walter E; Blank, Antje

    2015-09-01

    The QUALMAT project has successfully implemented an electronic clinical decision support system (eCDSS) for antenatal and intrapartum care in two sub-Saharan African countries. The system was introduced to facilitate adherence to clinical practice guidelines and to support decision making during client encounter to bridge the know-do gap of health workers. This study aimed to describe health workers' acceptance and use of the eCDSS for maternal care in rural primary health care (PHC) facilities of Ghana and Tanzania and to identify factors affecting successful adoption of such a system. This longitudinal study was conducted in Lindi rural district in Tanzania and Kassena-Nankana district in Ghana between October 2011 and December 2013 employing mixed methods. The study population included healthcare workers who were involved in the provision of maternal care in six rural PHC facilities from one district in each country where the eCDSS was implemented. All eCDSS users participated in the study with 61 and 56 participants at the midterm and final assessment, respectively. After several rounds of user training and support the eCDSS has been successfully adopted and constantly used during patient care in antenatal clinics and maternity wards. The eCDSS was used in 71% (2703/3798) and 59% (14,189/24,204) of all ANC clients in Tanzania and Ghana respectively, while it was also used in 83% (1185/1427) and 67% (1435/2144) of all deliveries in Tanzania and in Ghana, respectively. Several barriers reported to hinder eCDSS use were related to individual users, tasks, technology, and organization attributes. Implementation of an eCDSS in resource-constrained PHC facilities in sub-Saharan Africa was successful and the health workers accepted and continuously used the system for maternal care. Facilitators for eCDSS use included sufficient training and regular support whereas the challenges to sustained use were unreliable power supply and perceived high workload. However our

  7. Impact of intrapartum antimicrobial prophylaxis upon the intestinal microbiota and the prevalence of antibiotic resistance genes in vaginally delivered full-term neonates.

    Science.gov (United States)

    Nogacka, Alicja; Salazar, Nuria; Suárez, Marta; Milani, Christian; Arboleya, Silvia; Solís, Gonzalo; Fernández, Nuria; Alaez, Lidia; Hernández-Barranco, Ana M; de Los Reyes-Gavilán, Clara G; Ventura, Marco; Gueimonde, Miguel

    2017-08-08

    Disturbances in the early establishment of the intestinal microbiota may produce important implications for the infant's health and for the risk of disease later on. Different perinatal conditions may be affecting the development of the gut microbiota. Some of them, such as delivery mode or feeding habits, have been extensively assessed whereas others remain to be studied, being critical to identify their impact on the microbiota and, if any, to minimize it. Antibiotics are among the drugs most frequently used in early life, the use of intrapartum antimicrobial prophylaxis (IAP), present in over 30% of deliveries, being the most frequent source of exposure. However, our knowledge on the effects of IAP on the microbiota establishment is still limited. The aim of the present work was to evaluate the impact of IAP investigating a cohort of 40 full-term vaginally delivered infants born after an uncomplicated pregnancy, 18 of which were born from mothers receiving IAP. Fecal samples were collected at 2, 10, 30, and 90 days of age. We analyzed the composition of the fecal microbiota during the first 3 months of life by 16S rRNA gene sequencing and quantified fecal short chain fatty acids by gas chromatography. The presence of genes for resistance to antibiotics was determined by PCR in the samples from 1-month-old infants. Our results showed an altered pattern of intestinal microbiota establishment in IAP infants during the first weeks of life, with lower relative proportions of Actinobacteria and Bacteroidetes and increased of Preoteobacteria and Firmicutes. A delay in the increase on the levels of acetate was observed in IAP infants. The analyses of specific antibiotic resistance genes showed a higher occurrence of some β-lactamase coding genes in infants whose mothers received IAP. Our results indicate an effect of IAP on the establishing early microbiota during the first months of life, which represent a key moment for the development of the microbiota

  8. Effect of Repositioning Maneuver Type and Postmaneuver Restrictions on Vertigo and Dizziness in Benign Positional Paroxysmal Vertigo

    Science.gov (United States)

    Toupet, Michel; Ferrary, Evelyne; Bozorg Grayeli, Alexis

    2012-01-01

    Introduction. To compare the efficiency of Epley (Ep) and Sémont-Toupet (ST) repositioning maneuvers and to evaluate postmaneuver restriction effect on short-term vertigo and dizziness after repositioning maneuvers by an analog visual scale (VAS) in benign positional paroxysmal vertigo (BPPV). Material and Methods. 226 consecutive adult patients with posterior canal BPPV were included. Patients were randomized into 2 different maneuver sequence groups (n = 113): 2 ST then 1 Ep or 2 Ep then 1 ST. Each group of sequence was randomized into 2 subgroups: with or without postmaneuver restrictions. Vertigo and dizziness were assessed from days 0 to 5 by VAS. Results. There was no difference between vertigo scores between Ep and ST groups. Dizziness scores were higher in Ep group during the first 3 days but became similar to those of ST group at days 4 and 5. ST maneuvers induced liberatory signs more frequently than Ep (58% versus 42% resp., P < 0.01, Fisher's test). After repositioning maneuvers, VAS scores decreased similarly in patients with and without liberatory signs. Postmaneuver restrictions did not influence VAS scores. Conclusion. Even if ST showed a higher rate of liberatory signs than Ep in this series, VAS scores were not influenced by these signs. PMID:22973168

  9. Effect of Repositioning Maneuver Type and Postmaneuver Restrictions on Vertigo and Dizziness in Benign Positional Paroxysmal Vertigo

    Directory of Open Access Journals (Sweden)

    Michel Toupet

    2012-01-01

    Full Text Available Introduction. To compare the efficiency of Epley (Ep and Sémont-Toupet (ST repositioning maneuvers and to evaluate postmaneuver restriction effect on short-term vertigo and dizziness after repositioning maneuvers by an analog visual scale (VAS in benign positional paroxysmal vertigo (BPPV. Material and Methods. 226 consecutive adult patients with posterior canal BPPV were included. Patients were randomized into 2 different maneuver sequence groups (n=113: 2 ST then 1 Ep or 2 Ep then 1 ST. Each group of sequence was randomized into 2 subgroups: with or without postmaneuver restrictions. Vertigo and dizziness were assessed from days 0 to 5 by VAS. Results. There was no difference between vertigo scores between Ep and ST groups. Dizziness scores were higher in Ep group during the first 3 days but became similar to those of ST group at days 4 and 5. ST maneuvers induced liberatory signs more frequently than Ep (58% versus 42% resp., P<0.01, Fisher's test. After repositioning maneuvers, VAS scores decreased similarly in patients with and without liberatory signs. Postmaneuver restrictions did not influence VAS scores. Conclusion. Even if ST showed a higher rate of liberatory signs than Ep in this series, VAS scores were not influenced by these signs.

  10. Ocular VEMPs indicate repositioning of otoconia to the utricle after successful liberatory maneuvers in benign paroxysmal positioning vertigo

    Science.gov (United States)

    BREMOVA, TATIANA; BAYER, OTMAR; AGRAWAL, YURI; KREMMYDA, OLYMPIA; BRANDT, THOMAS; TEUFEL, JULIAN; STRUPP, MICHAEL

    2014-01-01

    Conclusions This study showed a transient increase of ocular vestibular evoked myogenic potential (oVEMP) amplitudes in the affected ear after successful liberatory maneuvers and no changes in cervical VEMP (cVEMP) amplitudes. These findings support the hypothesis that successful liberatory maneuvers can lead to a repositioning of otoconia to the utricle. Objectives To evaluate whether oVEMP amplitudes increase after successful liberatory maneuvers in patients with posterior semicircular canal benign paroxysmal positioning vertigo (pc-BPPV), while cVEMP amplitudes do not change. These findings may indicate a successful repositioning of dislodged otoconia to the utricular macula, but not to the saccular macula. Methods Thirty patients with unilateral pc-BPPV were prospectively examined with bone-conducted oVEMP and air-conducted cVEMP at four time points: before, after, 1 week after, and 1 month after the liberatory maneuvers (Sémont maneuvers). Results At the 1-week follow-up, 20 of 30 patients were asymptomatic (responders); BPPV could still be induced in the other 10 (non-responders). In responders the mean n10 amplitude on the affected side increased from 12 ± 6.5 μV at baseline (before the treatment) to 15.9 ± 7.1 μV at 1 week after treatment; this increase was significantly (p = 0.001) higher in responders than in non-responders. cVEMP did not differ significantly. PMID:24245699

  11. Transcatheter closure of large atrial septal defects with deficient aortic or posterior rims using the "Greek maneuver". A multicenter study.

    Science.gov (United States)

    Thanopoulos, Basil D; Dardas, Petros; Ninios, Vlasis; Eleftherakis, Nicholaos; Karanasios, Evangelos

    2013-10-09

    We report a modification ("Greek maneuver") of the standard atrial septal defect (ASD) closure technique using the Amplatzer septal occluder (ASO) to facilitate closure of large ASDs with deficient aortic or posterior rims. 185 patients (median 10.8, range 3 to 52 years) with large ASDs (mean diameter 26±7 mm, range 20-40 mm) with a deficient aortic (134 patients) or posterior (51 patients) rim underwent catheter closure with the ASO using the "Greek maneuver" under transesophageal guidance. The Greek maneuver is applied when protrusion of the aortic edge of the deployed left disk of the device in to the right atrium is detected by echo. To circumvent this left disk is recaptured and the whole delivery system is pushed inward and leftward into the left atrium where the left disk and the 2/3 of right disk are simultaneously released. This maneuver forces the left disk to become parallel to the septum preventing the protrusion of the device into the right atrium. The ASO was successfully implanted and was associated with complete closure in 175/185 (95%) of the patients. There were no early or late complications related to the procedure during a follow-up period ranging from 6 months to 7 years. The "Greek maneuver" is a simple quite useful trick that facilitates closure of large ASDs associated with or without deficient aortic or posterior rims. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  12. [Evaluation of upper airway and surrounding structures in patients with obstructive sleep apnea using cephalometry combined with Muller's maneuver].

    Science.gov (United States)

    Zhao, Yan-hui; Zhu, Min; Lu, Xiao-feng; Sun, Hong-xia; Nie, Ping; Xu, Xiao-long; Tao, Li

    2013-12-01

    To evaluate the upper airway and surrounding structures under intraluminal pressure using cephalometry combined with Muller's maneuver in obstructive sleep apnea and hypopnea syndrome (OSAHS) patients with different severity. Thirty-nine male patients were enrolled in our department during June 2011 to February 2012. Polysomnography (PSG) and anthropometric measurements data were recorded prior to the study. The lateral cephalograms of each patient were obtained during both the end-expiration phase and Muller's maneuver phase. The patients enrolled were classified into 3 groups according to the results of apnea-hypopnea index (AHI), including mild group (n=11), moderate group (n=14), and severe group (n=14). Craniofacial and upper airway structures were measured in lateral cephalometry by application of Cassos 2001 computed aided measurement software before and after the patients practicing Muller's maneuver. The data was analysed using SAS 9.13 software package. Muller's maneuver had a great influence on the upper airway and surrounding tissue, including increased thickness of the uvula, reduction in the anteroposterior dimension of retropalatal and increased vertical distance of the hyoid bone to the mandible in all groups (PCephalometry combined with Muller's maneuver can display how the intraluminal pressure function on the upper airway and surrounding tissues, and they also can distinguish some minor differences of the upper airway in patients with different security. Supported by Research Fund of Science and Technology Commission of Shanghai Municipality (11140902001).

  13. Analysis of impulsive maneuvers to keep orbits around the asteroid 2001SN263

    Science.gov (United States)

    Santos, Willer G.; Prado, Antonio F. B. A.; Oliveira, Geraldo M. C.; Santos, Leonardo B. T.

    2018-01-01

    The strongly perturbed environment of a small body, such as an asteroid, can complicate the prediction of orbits used for close proximity operations. Inaccurate predictions may make the spacecraft collide with the asteroid or escape to the deep space. The main forces acting in the dynamics come from the solar radiation pressure and from the body's weak gravity field. This paper investigates the feasibility of using bi-impulsive maneuvers to avoid the aforementioned non-desired phenomena (collisions and escapes) by connecting orbits around the triple system asteroid 2001SN263, which is the target of a proposed Brazilian space mission. In terms of a mathematical formulation, a recently presented rotating dipole model is considered with oblateness in both primaries. In addition, a "two-point boundary value problem" is solved to find a proper transfer trajectory. The results presented here give support to identifying the best strategy to find orbits for close proximity operations, in terms of long orbital lifetimes and low delta-V consumptions. Numerical results have also demonstrated the significant influence of the spacecraft orbital elements (semi-major axis and eccentricity), angular position of the Sun and spacecraft area-to-mass ratio, in the performance of the bi-impulsive maneuver.

  14. Directionality and maneuvering effects on a surface ship underwater acoustic signature.

    Science.gov (United States)

    Trevorrow, Mark V; Vasiliev, Boris; Vagle, Svein

    2008-08-01

    This work examines underwater source spectra of a small (560 tons, 40 m length), single-screw oceanographic vessel, focusing on directionality and effects of maneuvers. The measurements utilized a set of four, self-contained buoys with GPS positioning, each recording two calibrated hydrophones with effective acoustic bandwidth from 150 Hz to 5 kHz. In straight, constant-speed runs at speeds up to 6.2 m s(-1), the ship source spectra showed spectral levels in reasonable agreement with reference spectra. The broadband source level was observed to increase as approximately speed to the fourth power over the range of 2.6-6.1 m s(-1), partially biased at low speeds by nonpropulsion machinery signals. Source directionality patterns were extracted from variations in source spectra while the ship transited past the buoy field. The observed spectral source levels exhibited a broadside maximum, with bow and stern aspect reduced by approximately 12-9 dB, respectively, independent of frequency. An empirical model is proposed assuming that spectral source levels exhibit simultaneous variations in aspect angle, speed, and turn rate. After correction for source directionality and speed during turning maneuvers, an excess of up to 18 dB in one-third octave source levels was observed.

  15. Null motion strategy for spacecraft large angle agile maneuvering using hybrid actuators

    Science.gov (United States)

    Wu, Yun-Hua; Han, Feng; Hua, Bing; Chen, Zhi-Ming

    2017-11-01

    Control Moment Gyro (CMG) and Reaction Wheel (RW) generally serve in different spacecraft control tasks due to their unique characteristics, such as large output torque and control accuracy, respectively. The major concerns in using of CMG and RW are singularity and saturation, which could make spacecraft uncontrollable. RW as singularity escape equipment is adopted to construct hybrid actuator system named CMG & RW (CMGRW) to enhance and improve the spacecraft attitude performance as well as the CMG's. First, the attitude dynamic model of the spacecraft equipped with hybrid actuators is established and the corresponding singularity is analyzed thoroughly. Then null motion in CMGRW is further argued and proved feasible for both elliptical and hyperbolic singularities escape. A new performance index in terms of CMG and RW state is proposed, followed by a steering logic using gradient method with a feasible null motion vector to drive the hybrid actuator system to feasible states. Numerical simulations with initial conditions considering CMG singularity and RW saturation are selected to demonstrate the excellent performance of the hybrid actuators during the entire large angle agile maneuvering process, resulting in a group of feasible final states of the CMGRW that serves as great initial conditions for the next agile maneuvering.

  16. Residual dizziness after successful repositioning maneuver for idiopathic benign paroxysmal positional vertigo: a review

    Directory of Open Access Journals (Sweden)

    Giorgia Giommetti

    2017-05-01

    Full Text Available The benign paroxysmal positional vertigo (BPPV is a vestibular disorder cause of vertigo. The BPPV may be corrected mechanically by repositioning maneuvers but even after successful maneuvers, some patients report residual dizziness for a certain period afterward. Early recognition and treatment might decrease the incidence of residual dizziness in patients with BPPV, especially in those patients with psychiatric comorbidities and in the elderly, lowering the risk of falling. Many pathogenetic hypotheses for residual dizziness are under debate. The purpose of this review was to identify, evaluate and review recent researches about possible causal factors involved in residual dizziness and the implications on clinical practice. A literature search was performed using different databases such as Pubmed and Scopus. The following search terms were used: residual dizziness, otolithic membrane and BPPV. The search found a total of 1192 titles, which were reduced to 963 after a procedure of de-duplication of the found titles. The research was then restricted to an interval of time comprised between 2000 and 2016 for a total of 800 titles. Among these titles, only those including the terms benign paroxysmal positional vertigo were considered eligible for this review. Only publications in English language were taken into consideration and we excluded those with not available abstract. Finally, 90 abstracts were obtained and critically evaluated by two different Authors, and additional studies were identified by hand searching from the references of artiche of interest. Only 53 were included in this work.

  17. Effects of Semont maneuver on benign paroxysmal positional vertigo: a meta-analysis.

    Science.gov (United States)

    Zhang, Xiaoli; Qian, Xiaoyun; Lu, Ling; Chen, Jie; Liu, Jing; Lin, Chuanyao; Gao, Xia

    2017-01-01

    Benign paroxysmal positional vertigo (BPPV) is the most common type of peripheral vertigo. This study aimed to evaluate the effects of the Semont maneuver (SM) for BPPV treatment, compared with other methods. Studies were selected in relevant databases under pre-defined criteria up to June 2015. The Cochrane evaluation system was used to assess the quality of the studies. Effect size was indicated as a risk-ratio (RR) with corresponding 95% confidential interval (CI). Statistical analysis was conducted under a randomized- or fixed-effects model. Sub-group analysis was performed. Ten studies were included in the meta-analysis. All of the studies presented a low attrition bias, but a high selection and reporting bias. SM had a much higher recovery rate (SM vs no treatment: RR = 2.60, 95% CI = 1.97-3.44, p < 0.01; SM vs sham: RR = 4.89, 95% CI = 3.01-7.94, p < 0.01), and lower recurrence rate than those from controls (SM vs no treatment: RR = 0.11, 95% CI = 0.04-0.31, p < 0.01). Overall, SM had similar outcomes with Epley maneuver (EM) and Brandt-Daroff exercise (BDE) in terms of recovery rate, recurrence rate, and side-effects. SM is as effective as EM and BDE for BPPV treatment.

  18. Residual Dizziness after Successful Repositioning Maneuver for Idiopathic Benign Paroxysmal Positional Vertigo: A Review

    Science.gov (United States)

    Lapenna, Ruggero; Panichi, Roberto; Mobaraki, Puya Dehgani; Longari, Fabrizio; Ricci, Giampietro; Faralli, Mario

    2017-01-01

    The benign paroxysmal positional vertigo (BPPV) is a vestibular disorder cause of vertigo. The BPPV may be corrected mechanically by repositioning maneuvers but even after successful maneuvers, some patients report residual dizziness for a certain period afterward. Early recognition and treatment might decrease the incidence of residual dizziness in patients with BPPV, especially in those patients with psychiatric comorbidities and in the elderly, lowering the risk of falling. Many pathogenetic hypotheses for residual dizziness are under debate. The purpose of this review was to identify, evaluate and review recent researches about possible causal factors involved in residual dizziness and the implications on clinical practice. A literature search was performed using different databases such as Pubmed and Scopus. The following search terms were used: residual dizziness, otolithic membrane and BPPV. The search found a total of 1192 titles, which were reduced to 963 after a procedure of de-duplication of the found titles. The research was then restricted to an interval of time comprised between 2000 and 2016 for a total of 800 titles. Among these titles, only those including the terms benign paroxysmal positional vertigo were considered eligible for this review. Only publications in English language were taken into consideration and we excluded those with not available abstract. Finally, 90 abstracts were obtained and critically evaluated by two different Authors, and additional studies were identified by hand searching from the references of artiche of interest. Only 53 were included in this work. PMID:28603599

  19. Trajectories and orbital maneuvers for the ISEE-3/ICE comet mission

    Science.gov (United States)

    Farquhar, R.; Muhonen, D.; Church, L. C.

    1984-01-01

    The ISEE-3/ICE spacecraft, (launched in 1978), and expected to obtain the first measurements of comet Giacobinni-Zinner in September 1985, has undertaken a combination of propulsive maneuvers, lunar swing-bys, and solar perturbations to produce its present trajectory profile. ISEE-3 is a drum-shaped, spin-stabilized spacecraft equipped with a redundant pair of high-resolution sun sensors, a medium-gain S-band antenna, a hydrazine propulsion system and a science experiment payload. After being placed into a sun-earth libration halo orbit in late 1978, ISEE-3 was retargeted to the geomagnetotail in mid-1982 and became the first spacecraft to explore the geomagnetic tail between 80 and 237 earth radii in 1983. These types of maneuvers may prove important for future scientific missions planned as follow-ons to ISEE-3/ICE, such as a joint NASA/ISAS project spacecraft scheduled for Shuttle launch in 1991, and a possible encounter with two comets in 1996 anad 1998.

  20. Ultra-fast escape maneuver of an octopus-inspired robot.

    Science.gov (United States)

    Weymouth, G D; Subramaniam, V; Triantafyllou, M S

    2015-02-02

    We design and test an octopus-inspired flexible hull robot that demonstrates outstanding fast-starting performance. The robot is hyper-inflated with water, and then rapidly deflates to expel the fluid so as to power the escape maneuver. Using this robot we verify for the first time in laboratory testing that rapid size-change can substantially reduce separation in bluff bodies traveling several body lengths, and recover fluid energy which can be employed to improve the propulsive performance. The robot is found to experience speeds over ten body lengths per second, exceeding that of a similarly propelled optimally streamlined rigid rocket. The peak net thrust force on the robot is more than 2.6 times that on an optimal rigid body performing the same maneuver, experimentally demonstrating large energy recovery and enabling acceleration greater than 14 body lengths per second squared. Finally, over 53% of the available energy is converted into payload kinetic energy, a performance that exceeds the estimated energy conversion efficiency of fast-starting fish. The Reynolds number based on final speed and robot length is [Formula: see text]. We use the experimental data to establish a fundamental deflation scaling parameter [Formula: see text] which characterizes the mechanisms of flow control via shape change. Based on this scaling parameter, we find that the fast-starting performance improves with increasing size.