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Sample records for augments chemoreflex control

  1. Clinical consequences of altered chemoreflex control

    PubMed Central

    Plataki, Maria; Sands, Scott A.; Malhotra, Atul

    2015-01-01

    Control of ventilation dictates various breathing patterns. The respiratory control system consists of a central pattern generator and several feedback mechanisms that act to maintain ventilation at optimal levels. The concept of loop gain has been employed to describe its stability and variability. Synthesizing all interactions under a general model that could account for every behavior has been challenging. Recent insight into the importance of these feedback systems may unveil therapeutic strategies for common ventilatory disturbances. In this review we will address the major mechanisms that have been proposed as mediators of some of the breathing patterns in health and disease that have raised controversies and discussion on ventilatory control over the years. PMID:23681082

  2. Severe hemorrhage attenuates cardiopulmonary chemoreflex control of regional sympathetic outputs via NTS adenosine receptors.

    PubMed

    Minic, Zeljka; Li, Cailian; O'Leary, Donal S; Scislo, Tadeusz J

    2014-09-15

    Selective stimulation of inhibitory A1 and facilitatory A2a adenosine receptor subtypes located in the nucleus of the solitary tract (NTS) powerfully inhibits cardiopulmonary chemoreflex (CCR) control of regional sympathetic outputs via different mechanisms: direct inhibition of glutamate release and facilitation of an inhibitory neurotransmitter release, respectively. However, it remains unknown whether adenosine naturally released into the NTS has similar inhibitory effects on the CCR as the exogenous agonists do. Our previous study showed that adenosine is released into the NTS during severe hemorrhage and contributes to reciprocal changes of renal (decreases) and adrenal (increases) sympathetic nerve activity observed in this setting. Both A1 and A2a adenosine receptors are involved. Therefore, we tested the hypothesis that, during severe hemorrhage, CCR control of the two sympathetic outputs is attenuated by adenosine naturally released into the NTS. We compared renal and adrenal sympathoinhibitory responses evoked by right atrial injections of 5HT3 receptor agonist phenylbiguanide (2-8 μg/kg) under control conditions, during hemorrhage, and during hemorrhage preceded by blockade of NTS adenosine receptors with bilateral microinjections of 8-(p-sulfophenyl) theophylline (1 nmol/100 nl) in urethane/chloralose anesthetized rats. CCR-mediated inhibition of renal and adrenal sympathetic activity was significantly attenuated during severe hemorrhage despite reciprocal changes in the baseline activity levels, and this attenuation was removed by bilateral blockade of adenosine receptors in the caudal NTS. This confirmed that adenosine endogenously released into the NTS has a similar modulatory effect on integration of cardiovascular reflexes as stimulation of NTS adenosine receptors with exogenous agonists. PMID:25063794

  3. Nucleus tractus solitarii A(2a) adenosine receptors inhibit cardiopulmonary chemoreflex control of sympathetic outputs.

    PubMed

    Minic, Zeljka; O'Leary, Donal S; Scislo, Tadeusz J

    2014-02-01

    Previously we have shown that stimulation of inhibitory A1 adenosine receptors located in the nucleus tractus solitarii (NTS) attenuates cardiopulmonary chemoreflex (CCR) evoked inhibition of renal, adrenal and lumbar sympathetic nerve activity and reflex decreases in arterial pressure and heart rate. Activation of facilitatory A2a adenosine receptors, which dominate over A1 receptors in the NTS, contrastingly alters baseline activity of regional sympathetic outputs: it decreases renal, increases adrenal and does not change lumbar nerve activity. Considering that NTS A2a receptors may facilitate release of inhibitory transmitters we hypothesized that A2a receptors will act in concert with A1 receptors differentially inhibiting regional sympathetic CCR responses (adrenal>lumbar>renal). In urethane/chloralose anesthetized rats (n=38) we compared regional sympathetic responses evoked by stimulation of the CCR with right atrial injections of serotonin 5HT3 receptor agonist, phenylbiguanide, (1-8μg/kg) before and after selective stimulation, blockade or combined blockade and stimulation of NTS A2a adenosine receptors (microinjections into the NTS of CGS-21680 0.2-20pmol/50nl, ZM-241385 40pmol/100nl or ZM-241385+CGS-21680, respectively). We found that stimulation of A2a adenosine receptors uniformly inhibited the regional sympathetic and hemodynamic reflex responses and this effect was abolished by the selective blockade of NTS A2a receptors. This indicates that A2a receptor triggered inhibition of CCR responses and the contrasting shifts in baseline sympathetic activity are mediated via different mechanisms. These data implicate that stimulation of NTS A2a receptors triggers unknown inhibitory mechanism(s) which in turn inhibit transmission in the CCR pathway when adenosine is released into the NTS during severe hypotension. PMID:24216055

  4. Control Augmented Structural Synthesis

    NASA Technical Reports Server (NTRS)

    Lust, Robert V.; Schmit, Lucien A.

    1988-01-01

    A methodology for control augmented structural synthesis is proposed for a class of structures which can be modeled as an assemblage of frame and/or truss elements. It is assumed that both the plant (structure) and the active control system dynamics can be adequately represented with a linear model. The structural sizing variables, active control system feedback gains and nonstructural lumped masses are treated simultaneously as independent design variables. Design constraints are imposed on static and dynamic displacements, static stresses, actuator forces and natural frequencies to ensure acceptable system behavior. Multiple static and dynamic loading conditions are considered. Side constraints imposed on the design variables protect against the generation of unrealizable designs. While the proposed approach is fundamentally more general, here the methodology is developed and demonstrated for the case where: (1) the dynamic loading is harmonic and thus the steady state response is of primary interest; (2) direct output feedback is used for the control system model; and (3) the actuators and sensors are collocated.

  5. NTS adenosine A2a receptors inhibit the cardiopulmonary chemoreflex control of regional sympathetic outputs via a GABAergic mechanism.

    PubMed

    Minic, Zeljka; O'Leary, Donal S; Scislo, Tadeusz J

    2015-07-01

    Adenosine is a powerful central neuromodulator acting via opposing A1 (inhibitor) and A2a (activator) receptors. However, in the nucleus of the solitary tract (NTS), both adenosine receptor subtypes attenuate cardiopulmonary chemoreflex (CCR) sympathoinhibition of renal, adrenal, and lumbar sympathetic nerve activity and attenuate reflex decreases in arterial pressure and heart rate. Adenosine A1 receptors inhibit glutamatergic transmission in the CCR pathway, whereas adenosine A2a receptors most likely facilitate release of an unknown inhibitory neurotransmitter, which, in turn, inhibits the CCR. We hypothesized that adenosine A2a receptors inhibit the CCR via facilitation of GABA release in the NTS. In urethane-chloralose-anesthetized rats (n = 51), we compared regional sympathetic responses evoked by stimulation of the CCR with right atrial injections of the 5-HT3 receptor agonist phenylbiguanide (1-8 μg/kg) before and after selective stimulation of NTS adenosine A2a receptors [microinjections into the NTS of CGS-21680 (20 pmol/50 nl)] preceded by blockade of GABAA or GABAB receptors in the NTS [bicuculline (10 pmol/100 nl) or SCH-50911 (1 nmol/100 nl)]. Blockade of GABAA receptors virtually abolished adenosine A2a receptor-mediated inhibition of the CCR. GABAB receptors had much weaker but significant effects. These effects were similar for the different sympathetic outputs. We conclude that stimulation of NTS adenosine A2a receptors inhibits CCR-evoked hemodynamic and regional sympathetic reflex responses via a GABA-ergic mechanism. PMID:25910812

  6. Improved approximations for control augmented structural synthesis

    NASA Technical Reports Server (NTRS)

    Thomas, H. L.; Schmit, L. A.

    1990-01-01

    A methodology for control-augmented structural synthesis is presented for structure-control systems which can be modeled as an assemblage of beam, truss, and nonstructural mass elements augmented by a noncollocated direct output feedback control system. Truss areas, beam cross sectional dimensions, nonstructural masses and rotary inertias, and controller position and velocity gains are treated simultaneously as design variables. The structural mass and a control-system performance index can be minimized simultaneously, with design constraints placed on static stresses and displacements, dynamic harmonic displacements and forces, structural frequencies, and closed-loop eigenvalues and damping ratios. Intermediate design-variable and response-quantity concepts are used to generate new approximations for displacements and actuator forces under harmonic dynamic loads and for system complex eigenvalues. This improves the overall efficiency of the procedure by reducing the number of complete analyses required for convergence. Numerical results which illustrate the effectiveness of the method are given.

  7. Peripheral chemoreflex sensitivity and sympathetic nerve activity are normal in apnea divers during training season.

    PubMed

    Breskovic, Toni; Ivancev, Vladimir; Banic, Ivana; Jordan, Jens; Dujic, Zeljko

    2010-04-19

    Apnea divers are exposed to repeated massive arterial oxygen desaturation, which could perturb chemoreflexes. An earlier study suggested that peripheral chemoreflex regulation of sympathetic vasomotor tone and ventilation may have recovered 4 or more weeks into the off season. Therefore, we tested the hypothesis that peripheral chemoreflex regulation of ventilation and sympathetic vasomotor tone is present during the training season. We determined ventilation, heart rate, blood pressure, cardiac stroke volume, and muscle sympathetic nerve activity (MSNA) during isocapnic hypoxia in 10 breath hold divers and 11 matched control subjects. The study was carried out at the end of the season of intense apnea trainings. Baseline MSNA frequency was 30+/-4bursts/min in control subjects and 25+/-4bursts/min in breath hold divers (P=0.053). During hypoxia burst frequency and total sympathetic activity increased similarly in both groups. Sympathetic activity normalized during the 30-minute recovery. Hypoxia-induced stimulation of minute ventilation was similar in both groups, although in divers it was maintained by higher tidal volumes and lower breathing frequency compared with control subjects. In both groups, hypoxia increased heart rate and cardiac output whereas total peripheral resistance decreased. Blood pressure remained unchanged. We conclude that peripheral chemoreflex regulation of ventilation and sympathetic vasomotor tone is paradoxically preserved in apnea divers, both, during the off and during the training season. The observation suggests that repeated arterial oxygen desaturation may not be sufficient explaining sympathetic reflex abnormalities similar to those in obstructive sleep apnea patients. PMID:19926535

  8. Chemoreflexes, Sleep Apnea, and Sympathetic Dysregulation

    PubMed Central

    Mansukhani, Meghna P.; Kara, Tomas; Caples, Sean; Somers, Virend K.

    2014-01-01

    Obstructive sleep apnea (OSA) and hypertension are closely linked conditions. Disordered breathing events in OSA are characterized by increasing efforts against an occluded airway whilst asleep, resulting in a marked sympathetic response. This is predominantly due to hypoxemia activating the chemoreflexes, resulting in reflex increases in sympathetic neural outflow. In addition, apnea, and the consequent lack of inhibition of the sympathetic system that occurs with lung inflation during normal breathing, potentiates central sympathetic outflow. Sympathetic activation persists into the daytime, and is thought to contribute to hypertension and other adverse cardiovascular outcomes. This review discusses chemoreflex physiology and sympathetic modulation during normal sleep, as well as the sympathetic dysregulation seen in OSA, its extension into wakefulness, and changes after treatment. Evidence supporting the role of the peripheral chemoreflex in the sympathetic dysregulation seen in OSA, including in the context of co-morbid obesity, metabolic syndrome and systemic hypertension is reviewed. Finally, alterations in cardiovascular variability and other potential mechanisms that might play a role in the autonomic imbalance seen in OSA are also discussed. PMID:25097113

  9. Control augmentation for lateral control wheel steering

    NASA Technical Reports Server (NTRS)

    Foulkes, R. H., Jr.

    1981-01-01

    Flight control system design for lateral control wheel steering is discussed. Two alternate designs are presented. The first design is a roll-rate command, bank-angle hold system with a wings-level track-hold submode. The second is a curved-track-hold system. Design details and real-time flight simulator results are included.

  10. Pulmonary chemoreflex and phrenic sympathetic efferents.

    PubMed

    Bałkowiec, A; Szulczyk, P

    1993-11-01

    The pulmonary chemoreflex components such as reactions of phrenic sympathetic neuron (PhSN) activity, phrenic nerve activity, heart rate and blood pressure were tested in chloralose-anesthetized, paralyzed cats. 10 micrograms to 160 micrograms phenylbiguanide (PBG) in 0.9% NaCl was injected into the pulmonary circulation. PBG injected into the right atrium (in 11 of 19 experiments) and into the pulmonary artery (in 5 of 8 experiments), evoked short-latency (1-1.4 sec) dose-dependent increase in PhSN activity accompanied by increase in blood pressure, and followed by decrease in these two variables. In all experiments, activity of the phrenic nerve was depressed, and bradycardia occurred after PBG injection. All responses to PBG injections into the pulmonary artery were abolished following bilateral vagotomy. In the same procedure related to the right atrium after vagotomy, the increases in PhSN activity and blood pressure were also abolished, although a decrease in heart rate, PhSN activity and in the amplitude of phrenic nerve discharges together with an increase in their frequency persisted. Our results suggest that short-latency increase in PhSN activity is a component of pulmonary chemoreflex. PMID:8272587

  11. Acceleration-Augmented LQG Control of an Active Magnetic Bearing

    NASA Technical Reports Server (NTRS)

    Feeley, Joseph J.

    1993-01-01

    A linear-quadratic-gaussian (LQG) regulator controller design for an acceleration-augmented active magnetic bearing (AMB) is outlined. Acceleration augmentation is a key feature in providing improved dynamic performance of the controller. The optimal control formulation provides a convenient method of trading-off fast transient response and force attenuation as control objectives.

  12. A preliminary look at control augmented dynamic response of structures

    NASA Technical Reports Server (NTRS)

    Ryan, R. S.; Jewell, R. E.

    1983-01-01

    The augmentation of structural characteristics, mass, damping, and stiffness through the use of control theory in lieu of structural redesign or augmentation was reported. The standard single-degree-of-freedom system was followed by a treatment of the same system using control augmentation. The system was extended to elastic structures using single and multisensor approaches and concludes with a brief discussion of potential application to large orbiting space structures.

  13. Relevance of the Carotid Body Chemoreflex in the Progression of Heart Failure

    PubMed Central

    Andrade, David C.; Lucero, Claudia; Toledo, Camilo; Madrid, Carlos; Marcus, Noah J.; Schultz, Harold D.; Del Rio, Rodrigo

    2015-01-01

    Chronic heart failure (CHF) is a global health problem affecting millions of people. Autonomic dysfunction and disordered breathing patterns are commonly observed in patients with CHF, and both are strongly related to poor prognosis and high mortality risk. Tonic activation of carotid body (CB) chemoreceptors contributes to sympathoexcitation and disordered breathing patterns in experimental models of CHF. Recent studies show that ablation of the CB chemoreceptors improves autonomic function and breathing control in CHF and improves survival. These exciting findings indicate that alterations in CB function are critical to the progression of CHF. Therefore, better understanding of the physiology of the CB chemoreflex in CHF could lead to improvements in current treatments and clinical management of patients with CHF characterized by high chemosensitivity. Accordingly, the main focus of this brief review is to summarize current knowledge of CB chemoreflex function in different experimental models of CHF and to comment on their potential translation to treatment of human CHF. PMID:26779536

  14. Backstepping Control Augmented by Neural Networks For Robot Manipulators

    NASA Astrophysics Data System (ADS)

    Belkheiri, Mohammed; Boudjema, Farès

    2008-06-01

    A new control approach is proposed to address the tracking problem of robot manipulators. In this approach, one relies first on a partially known model to the system to be controlled using a backstepping control strategy. The obtained controller is then augmented by an online neural network that serves as an approximator for the neglected dynamics and modeling errors. The proposed approach is systematic, and exploits the known nonlinear dynamics to derive the stepwise virtual stabilizing control laws. At the final step, an augmented Lyapunov function is introduced to derive the adaptation laws of the network weights. The effectiveness of the proposed controller is demonstrated through computer simulation on PUMA 560 robot.

  15. Augmented thermal bus wih multiple thermoelectric devices individually controlled

    NASA Technical Reports Server (NTRS)

    Schrage, Dean S. (Inventor)

    1994-01-01

    The present invention is directed to an augmented thermal bus. In the present design a plurality of thermo-electric heat pumps are used to couple a source plate to a sink plate. Each heat pump is individually controlled by a model based controller. The controller coordinates the heat pumps to maintain isothermality in the source.

  16. Experimental Investigations of Generalized Predictive Control for Tiltrotor Stability Augmentation

    NASA Technical Reports Server (NTRS)

    Nixon, Mark W.; Langston, Chester W.; Singleton, Jeffrey D.; Piatak, David J.; Kvaternik, Raymond G.; Bennett, Richard L.; Brown, Ross K.

    2001-01-01

    A team of researchers from the Army Research Laboratory, NASA Langley Research Center (LaRC), and Bell Helicopter-Textron, Inc. have completed hover-cell and wind-tunnel testing of a 1/5-size aeroelastically-scaled tiltrotor model using a new active control system for stability augmentation. The active system is based on a generalized predictive control (GPC) algorithm originally developed at NASA LaRC in 1997 for un-known disturbance rejection. Results of these investigations show that GPC combined with an active swashplate can significantly augment the damping and stability of tiltrotors in both hover and high-speed flight.

  17. Digital control of highly augmented combat rotorcraft

    NASA Technical Reports Server (NTRS)

    Tischler, Mark B.

    1987-01-01

    Proposed concepts for the next generation of combat helicopters are to be embodied in a complex, highly maneuverable, multiroled vehicle with avionics systems. Single pilot and nap-of-the-Earth operations require handling qualities which minimize the involvement of the pilot in basic stabilization tasks. To meet these requirements will demand a full authority, high-gain, multimode, multiply-redundant, digital flight-control system. The gap between these requirements and current low-authority, low-bandwidth operational rotorcraft flight-control technology is considerable. This research aims at smoothing the transition between current technology and advanced concept requirements. The state of the art of high-bandwidth digital flight-control systems are reviewed; areas of specific concern for flight-control systems of modern combat are exposed; and the important concepts are illustrated in design and analysis of high-gain, digital systems with a detailed case study involving a current rotorcraft system. Approximate and exact methods are explained and illustrated for treating the important concerns which are unique to digital systems.

  18. Carotid Body Chemoreflex Mediates Intermittent Hypoxia-Induced Oxidative Stress in the Adrenal Medulla

    PubMed Central

    Kumar, Ganesh K.; Peng, Ying-Jie; Nanduri, Jayasri; Prabhakar, Nanduri R.

    2016-01-01

    Intermittent hypoxia (IH) increases reactive oxygen species generation resulting in oxidative stress in the adrenal medulla (AM), a major end-organ of the sympathetic nervous system which facilitates catecholamine secretion by hypoxia. Here, we show that carotid body chemoreflex contributes to IH-induced oxidative stress in the AM. Carotid bodies were ablated by cryocoagulation of glomus cells, the putative O2 sensing cells. Carotid body ablated (CBA) and control rats were exposed to IH and the redox state of the AM was assessed biochemically. We found that IH raised reactive oxygen species levels along with an increase in NADPH oxidase (Nox), a pro-oxidant enzyme and a decrease in superoxide dismutase-2 (SOD2), an anti-oxidant enzyme. Further, IH increased hypoxia-inducible factor (HIF)-1α, whereas decreased HIF-2α, the transcriptional regulator of Nox and SOD-2, respectively. These IH-induced changes in the AM were absent in CBA rats. Moreover, IH increased splanchnic nerve activity and facilitated hypoxia-evoked catecholamine efflux from the AM and CBA prevented these effects. These findings suggest that IH-induced oxidative stress and catecholamine efflux in the AM occurs via carotid body chemoreflex involving HIF α isoform mediated imbalance in pro-, and anti-oxidant enzymes. PMID:26303481

  19. Pilots Rate Augmented Generalized Predictive Control for Reconfiguration

    NASA Technical Reports Server (NTRS)

    Soloway, Don; Haley, Pam

    2004-01-01

    The objective of this paper is to report the results from the research being conducted in reconfigurable fight controls at NASA Ames. A study was conducted with three NASA Dryden test pilots to evaluate two approaches of reconfiguring an aircraft's control system when failures occur in the control surfaces and engine. NASA Ames is investigating both a Neural Generalized Predictive Control scheme and a Neural Network based Dynamic Inverse controller. This paper highlights the Predictive Control scheme where a simple augmentation to reduce zero steady-state error led to the neural network predictor model becoming redundant for the task. Instead of using a neural network predictor model, a nominal single point linear model was used and then augmented with an error corrector. This paper shows that the Generalized Predictive Controller and the Dynamic Inverse Neural Network controller perform equally well at reconfiguration, but with less rate requirements from the actuators. Also presented are the pilot ratings for each controller for various failure scenarios and two samples of the required control actuation during reconfiguration. Finally, the paper concludes by stepping through the Generalized Predictive Control's reconfiguration process for an elevator failure.

  20. Spinal cord injury is associated with enhanced peripheral chemoreflex sensitivity.

    PubMed

    Bascom, Amy T; Sankari, Abdulghani; Badr, M Safwan

    2016-09-01

    Sleep-disordered breathing (SDB) is prevalent in individuals with chronic spinal cord injury (SCI), but the exact mechanism is unknown. The aim of this study was to investigate whether peripheral chemoreceptors activity is enhanced in individuals with chronic SCI compared to abled-bodied control subjects using CO2 and O2 chemical tests. In protocol (1) 30 subjects (8 cervical [cSCI], 7 thoracic [tSCI] and 15 able-bodied [AB]) were studied to determine the ventilatory response to hyperoxia during wakefulness in the supine position. In protocol (2) 24 subjects (6 cSCI, 6 tSCI, and 12 AB subjects) were studied to determine the ventilatory response to a single breath of CO2 (SBCO2). The chemoreflex response to SBCO2 was calculated as ∆VE/∆CO2 (L/min/mmHg). The ventilatory response to hyperoxia was defined as the % change in VT following acute hyperoxia compared to preceding baseline. During hyperoxia SCI subjects had a significant decrease in VT and VE (63.4 ± 21.7% and 63.1 ± 23.0% baseline, respectively, P < 0.05) compared to AB (VT: 87.1 ± 14.3% and VE: 91.38 ± 15.1% baseline, respectively, P < 0.05). There was no significant difference between cSCI and tSCI in the VT or VE during hyperoxia (P = NS). There was no significant correlation between AHI and VE% baseline (r = -0.28) in SCI and AB (n = 30). SCI participants had a greater ventilatory response to an SBCO2 than AB (0.78 ± 0.42 L/min/mmHg vs. 0.26 ± 0.10 L/min/mmHg, respectively, P < 0.05). Peripheral ventilatory chemoresponsiveness is elevated in individuals with chronic SCI compared to able-bodied individuals. PMID:27597767

  1. Space Launch System Implementation of Adaptive Augmenting Control

    NASA Technical Reports Server (NTRS)

    VanZwieten, Tannen S.; Wall, John H.; Orr, Jeb S.

    2014-01-01

    Given the complex structural dynamics, challenging ascent performance requirements, and rigorous flight certification constraints owing to its manned capability, the NASA Space Launch System (SLS) launch vehicle requires a proven thrust vector control algorithm design with highly optimized parameters to robustly demonstrate stable and high performance flight. On its development path to preliminary design review (PDR), the stability of the SLS flight control system has been challenged by significant vehicle flexibility, aerodynamics, and sloshing propellant dynamics. While the design has been able to meet all robust stability criteria, it has done so with little excess margin. Through significant development work, an adaptive augmenting control (AAC) algorithm previously presented by Orr and VanZwieten, has been shown to extend the envelope of failures and flight anomalies for which the SLS control system can accommodate while maintaining a direct link to flight control stability criteria (e.g. gain & phase margin). In this paper, the work performed to mature the AAC algorithm as a baseline component of the SLS flight control system is presented. The progress to date has brought the algorithm design to the PDR level of maturity. The algorithm has been extended to augment the SLS digital 3-axis autopilot, including existing load-relief elements, and necessary steps for integration with the production flight software prototype have been implemented. Several updates to the adaptive algorithm to increase its performance, decrease its sensitivity to expected external commands, and safeguard against limitations in the digital implementation are discussed with illustrating results. Monte Carlo simulations and selected stressing case results are shown to demonstrate the algorithm's ability to increase the robustness of the integrated SLS flight control system.

  2. Space Launch System Implementation of Adaptive Augmenting Control

    NASA Technical Reports Server (NTRS)

    Wall, John H.; Orr, Jeb S.; VanZwieten, Tannen S.

    2014-01-01

    Given the complex structural dynamics, challenging ascent performance requirements, and rigorous flight certification constraints owing to its manned capability, the NASA Space Launch System (SLS) launch vehicle requires a proven thrust vector control algorithm design with highly optimized parameters to provide stable and high-performance flight. On its development path to Preliminary Design Review (PDR), the SLS flight control system has been challenged by significant vehicle flexibility, aerodynamics, and sloshing propellant. While the design has been able to meet all robust stability criteria, it has done so with little excess margin. Through significant development work, an Adaptive Augmenting Control (AAC) algorithm has been shown to extend the envelope of failures and flight anomalies the SLS control system can accommodate while maintaining a direct link to flight control stability criteria such as classical gain and phase margin. In this paper, the work performed to mature the AAC algorithm as a baseline component of the SLS flight control system is presented. The progress to date has brought the algorithm design to the PDR level of maturity. The algorithm has been extended to augment the full SLS digital 3-axis autopilot, including existing load-relief elements, and the necessary steps for integration with the production flight software prototype have been implemented. Several updates which have been made to the adaptive algorithm to increase its performance, decrease its sensitivity to expected external commands, and safeguard against limitations in the digital implementation are discussed with illustrating results. Monte Carlo simulations and selected stressing case results are also shown to demonstrate the algorithm's ability to increase the robustness of the integrated SLS flight control system.

  3. Synthesis of the unmanned aerial vehicle remote control augmentation system

    NASA Astrophysics Data System (ADS)

    Tomczyk, Andrzej

    2014-12-01

    Medium size Unmanned Aerial Vehicle (UAV) usually flies as an autonomous aircraft including automatic take-off and landing phases. However in the case of the on-board control system failure, the remote steering is using as an emergency procedure. In this reason, remote manual control of unmanned aerial vehicle is used more often during take-of and landing phases. Depends on UAV take-off mass and speed (total energy) the potential crash can be very danger for airplane and environment. So, handling qualities of UAV is important from pilot-operator point of view. In many cases the dynamic properties of remote controlling UAV are not suitable for obtaining the desired properties of the handling qualities. In this case the control augmentation system (CAS) should be applied. Because the potential failure of the on-board control system, the better solution is that the CAS algorithms are placed on the ground station computers. The method of UAV handling qualities shaping in the case of basic control system failure is presented in this paper. The main idea of this method is that UAV reaction on the operator steering signals should be similar - almost the same - as reaction of the "ideal" remote control aircraft. The model following method was used for controller parameters calculations. The numerical example concerns the medium size MP-02A UAV applied as an aerial observer system.

  4. Synthesis of the unmanned aerial vehicle remote control augmentation system

    SciTech Connect

    Tomczyk, Andrzej

    2014-12-10

    Medium size Unmanned Aerial Vehicle (UAV) usually flies as an autonomous aircraft including automatic take-off and landing phases. However in the case of the on-board control system failure, the remote steering is using as an emergency procedure. In this reason, remote manual control of unmanned aerial vehicle is used more often during take-of and landing phases. Depends on UAV take-off mass and speed (total energy) the potential crash can be very danger for airplane and environment. So, handling qualities of UAV is important from pilot-operator point of view. In many cases the dynamic properties of remote controlling UAV are not suitable for obtaining the desired properties of the handling qualities. In this case the control augmentation system (CAS) should be applied. Because the potential failure of the on-board control system, the better solution is that the CAS algorithms are placed on the ground station computers. The method of UAV handling qualities shaping in the case of basic control system failure is presented in this paper. The main idea of this method is that UAV reaction on the operator steering signals should be similar - almost the same - as reaction of the 'ideal' remote control aircraft. The model following method was used for controller parameters calculations. The numerical example concerns the medium size MP-02A UAV applied as an aerial observer system.

  5. Control and Augmentation of Passive Porosity through Transpiration Control

    NASA Technical Reports Server (NTRS)

    Banks, Daniel W. (Inventor); Wood, Richard M. (Inventor); Bauer, Steven X. S. (Inventor)

    1999-01-01

    A device for controlling pressure loading of a member caused by a fluid moving past the member or the member moving through a fluid. The device consists of a porous skin mounted over the solid surface of the member and separated from the solid surface by a plenum. Fluid from an area exerting high pressure on the member may enter the plenum through the porous surface and exit into an area exerting a lower pressure on the member, thus controlling pressure loading of the member. A transpirational control device controls the conditions within the plenum thus controlling the side force and yaw moment on the forebody.

  6. CMG-Augmented Control of a Hovering VTOL Platform

    NASA Technical Reports Server (NTRS)

    Lim, K. B.; Moerder, D. D.

    2007-01-01

    This paper describes how Control Moment Gyroscopes (CMGs) can be used for stability augmentation to a thrust vectoring system for a generic Vertical Take-Off and Landing platform. The response characteristics of the platform which uses only thrust vectoring and a second configuration which includes a single-gimbal CMG array are simulated and compared for hovering flight while subject to severe air turbulence. Simulation results demonstrate the effectiveness of a CMG array in its ability to significantly reduce the agility requirement on the thrust vectoring system. Albeit simplifying physical assumptions on a generic CMG configuration, the numerical results also suggest that reasonably sized CMGs will likely be sufficient for a small hovering vehicle.

  7. Menstrual cycle and sex effects on sympathetic responses to acute chemoreflex stress.

    PubMed

    Usselman, Charlotte W; Gimon, Tamara I; Nielson, Chantelle A; Luchyshyn, Torri A; Coverdale, Nicole S; Van Uum, Stan H M; Shoemaker, J Kevin

    2015-03-15

    This study aimed to examine the effects of sex (males vs. females) and sex hormones (menstrual cycle phases in women) on sympathetic responsiveness to severe chemoreflex activation in young, healthy individuals. Muscle sympathetic nerve activity (MSNA) was measured at baseline and during rebreathing followed by a maximal end-inspiratory apnea. In women, baseline MSNA was greater in the midluteal (ML) than early-follicular (EF) phase of the menstrual cycle. Baseline MSNA burst incidence was greater in men than women, while burst frequency and total MSNA were similar between men and women only in the ML phase. Chemoreflex activation evoked graded increases in MSNA burst frequency, amplitude, and total activity in all participants. In women, this sympathoexcitation was greater in the EF than ML phase. The sympathoexcitatory response to chemoreflex stimulation of the EF phase in women was also greater than in men. Nonetheless, changes in total peripheral resistance were similar between sexes and menstrual cycle phases. This indicates that neurovascular transduction was attenuated during the EF phase during chemoreflex activation, thereby offsetting the exaggerated sympathoexcitation. Chemoreflex-induced increases in mean arterial pressure were similar across sexes and menstrual cycle phases. During acute chemoreflex stimulation, reduced neurovascular transduction could provide a mechanism by which apnea-associated morbidity might be attenuated in women relative to men. PMID:25527774

  8. Carotid body chemoreflex: a driver of autonomic abnormalities in sleep apnoea.

    PubMed

    Prabhakar, Nanduri R

    2016-08-01

    What is the topic of this review? This article presents emerging evidence for heightened carotid body chemoreflex activity as a major driver of sympathetic activation and hypertension in sleep apnoea patients. What advances does it heighlight? This article discusses the recent advances on cellular, molecular and epigenetic mechanisms underlying the exaggerated chemoreflex in experimental models of sleep apnoea. The carotid bodies are the principal peripheral chemoreceptors for detecting changes in arterial blood oxygen concentration, and the resulting chemoreflex is a potent regulator of the sympathetic tone, blood pressure and breathing. Sleep apnoea is a disease of the respiratory system that affects several million adult humans. Apnoeas occur during sleep, often as a result of obstruction of the upper airway (obstructive sleep apnoea) or because of defective respiratory rhythm generation by the CNS (central sleep apnoea). Patients with sleep apnoea exhibit several co-morbidities, with the most notable among them being heightened sympathetic nerve activity and hypertension. Emerging evidence suggests that intermittent hypoxia resulting from periodic apnoea stimulates the carotid body, and the ensuing chemoreflex mediates the increased sympathetic tone and hypertension in sleep apnoea patients. Rodent models of intermittent hypoxia that simulate the O2 saturation profiles encountered during sleep apnoea have provided important insights into the cellular and molecular mechanisms underlying the heightened carotid body chemoreflex. This article describes how intermittent hypoxia affects the carotid body function and discusses the cellular, molecular and epigenetic mechanisms underlying the exaggerated chemoreflex. PMID:27474260

  9. Interactions between CO2 chemoreflexes and arterial baroreflexes.

    PubMed

    Henry, R A; Lu, I L; Beightol, L A; Eckberg, D L

    1998-06-01

    We studied interactions between CO2 chemoreflexes and arterial baroreflexes in 10 supine healthy young men and women. We measured vagal carotid baroreceptor-cardiac reflexes and steady-state fast Fourier transform R-R interval and photoplethysmographic arterial pressure power spectra at three arterial pressure levels (nitroprusside, saline, and phenylephrine infusions) and three end-tidal CO2 levels (3, 4, and 5%, fixed-frequency, large-tidal-volume breathing, CO2 plus O2). Our study supports three principal conclusions. First, although low levels of CO2 chemoreceptor stimulation reduce R-R intervals and R-R interval variability, statistical modeling suggests that this effect is indirect rather than direct and is mediated by reductions of arterial pressure. Second, reductions of R-R intervals during hypocapnia reflect simple shifting of vagally mediated carotid baroreflex responses on the R-R interval axis rather than changes of baroreflex gain, range, or operational point. Third, the influence of CO2 chemoreceptor stimulation on arterial pressure (and, derivatively, on R-R intervals and R-R interval variability) depends critically on baseline arterial pressure levels: chemoreceptor effects are smaller when pressure is low and larger when arterial pressure is high. PMID:9841543

  10. Chemoreflex Physiology and Implications for Sleep Apnea – Insights from Studies in Humans

    PubMed Central

    Mansukhani, Meghna P.; Wang, Shihan; Somers, Virend K.

    2015-01-01

    Activation of the chemoreflex in response to hypoxemia results in an increase in sympathetic neural outflow. This process is predominantly mediated by the peripheral chemoreceptors in the carotid bodies and is potentiated by the absence of the sympatho-inhibitory influence of ventilation during apnea, as is seen in patients with sleep apnea. In these patients, repetitive nocturnal hyoxemia and apnea elicit sympathetic activation, which may persist into wakefulness, and is thought to contribute to the development of systemic hypertension, and cardiac and vascular dysfunction. Chemoreflex activation could possibly lead to adverse cardiovascular outcomes such as nocturnal myocardial infarction, systolic and/or diastolic heart failure, cardiac arrhythmias and sudden death in patients with sleep apnea. This review summarizes chemoreflex physiology in health and disease, with specific focus on chemoreflex-mediated pathophysiology in obstructive and central sleep apnea. Measurement of the chemoreflex response may serve as a potential avenue for individualized screening for cardiovascular disease. Whether modulation of this response in sleep apnea may aid in the prevention and treatment of adverse cardiovascular consequences will require further study. PMID:25398715

  11. Propulsion augmented control/lift surface validation for missile maneuver application

    NASA Astrophysics Data System (ADS)

    Mask, R. L.; Spangler, J. G.; Haight, C. H.

    1982-04-01

    Improved maneuverability and controllability are prime goals in meeting a broad spectrum of tactical missile requirements. Configuration based on the Vought "Propulsion Augmented Control/Lift Surface' (PACS) approach to aeropropulsive integration are candidates for satisfying these requirements. The PACS concept utilizes a jet issuing from a trailing edge nozzle to induce augmented control loadings over fin or wing planforms. The current work provides experimental validation of PACS feasibility for a representative missile fin geometry at typical supersonic/transonic conditions.

  12. Chemoreflex and baroreflex alterations in Parkinsonism induced by 6-OHDA in unanesthetized rats.

    PubMed

    Ariza, Deborah; Lopes, Fernanda Novi Cortegoso; Crestani, Carlos Cesar; Martins-Pinge, Marli Cardoso

    2015-10-21

    Parkinson's disease (PD) is mainly characterized by motor signals. However, non-motor signals also affect and decrease the quality of life of PD patients. Among these non-motor signs are cardiovascular disorders as orthostatic hypotension, postprandial hypotension and cardiac arrhythmias, which may be due to the involvement of both central nervous system and peripheral autonomic nervous system. In the present study we investigated the cardiovascular function, evaluating cardiovascular reflexes (chemoreflex and baroreflex), in an animal model of Parkinsonism induced by bilateral infusion of the toxin 6-hydroxydopamine (6-OHDA), in the substantia nigra pars compacta (SNpc). The results showed that the animals induced to Parkinsonism had lower arterial pressure (AP) and heart rate HR) compared to control animals. We showed that after activation of the baroreceptors by phenylephrine (Phe) and sodium nitroprusside (SNP), the baroreflex sensitivity index was not changed between the groups. However, there was a greater increase in the AP when stimulated with Phe and greater tachycardia when stimulated with SNP in 6-OHDA animals. After activation of the peripheral chemoreceptors through KCN injection (cytotoxic hypoxia), there was a higher increase in pressor and bradycardic response in injured animals with bilateral 6-OHDA. These changes in the cardiovascular reflexes may be important adjustments mechanisms to maintain the cerebral blood flow in those animals, and may be a result of denervation supersensitivity to catecholamines in autonomic targets. PMID:26409036

  13. Peripheral chemoreflex inhibition with low-dose dopamine: new insight into mechanisms of extreme apnea.

    PubMed

    Bain, Anthony R; Dujic, Zeljko; Hoiland, Ryan L; Barak, Otto F; Madden, Dennis; Drvis, Ivan; Stembridge, Mike; MacLeod, David B; MacLeod, Douglas M; Ainslie, Philip N

    2015-11-01

    The purpose of this study was to determine the impact of peripheral chemoreflex inhibition with low-dose dopamine on maximal apnea time, and the related hemodynamic and cerebrovascular responses in elite apnea divers. In a randomized order, participants performed a maximal apnea while receiving either intravenous 2 μg·kg(-1)·min(-1) dopamine or volume-matched saline (placebo). The chemoreflex and hemodynamic response to dopamine was also assessed during hypoxia [arterial O2 tension, (PaO2 ) ∼35 mmHg] and mild hypercapnia [arterial CO2 tension (PaCO2 ) ∼46 mmHg] that mimicked the latter parts of apnea. Outcome measures included apnea duration, arterial blood gases (radial), heart rate (HR, ECG), mean arterial pressure (MAP, intra-arterial), middle (MCAv) and posterior (PCAv) cerebral artery blood velocity (transcranial ultrasound), internal carotid (ICA) and vertebral (VA) artery blood flow (ultrasound), and the chemoreflex responses. Although dopamine depressed the ventilatory response by 27 ± 41% (vs. placebo; P = 0.01), the maximal apnea duration was increased by only 5 ± 8% (P = 0.02). The PaCO2 and PaO2 at apnea breakpoint were similar (P > 0.05). When compared with placebo, dopamine increased HR and decreased MAP during both apnea and chemoreflex test (P all <0.05). At rest, dopamine compared with placebo dilated the ICA (3.0 ± 4.1%, P = 0.05) and VA (6.6 ± 5.0%, P < 0.01). During apnea and chemoreflex test, conductance of the cerebral vessels (ICA, VA, MCAv, PCAv) was increased with dopamine; however, flow (ICA and VA) was similar. At least in elite apnea divers, the small increase in apnea time and similar PaO2 at breakpoint (∼31 mmHg) suggest the apnea breakpoint is more related to PaO2 , rather than peripheral chemoreflex drive to breathe. PMID:26290106

  14. Controlling Bone Graft Substitute Microstructure to Improve Bone Augmentation.

    PubMed

    Sheikh, Zeeshan; Drager, Justin; Zhang, Yu Ling; Abdallah, Mohamed-Nur; Tamimi, Faleh; Barralet, Jake

    2016-07-01

    Vertical bone augmentation procedures are frequently carried out to allow successful placement of dental implants in otherwise atrophic ridges and represent one of the most common bone grafting procedures currently performed. Onlay autografting is one of the most prevalent and predictable techniques to achieve this; however, there are several well documented complications and drawbacks associated with it and synthetic alternatives are being sought. Monetite is a bioresorbable dicalcium phosphate with osteoconductive and osteoinductive potential that has been previously investigated for onlay bone grafting and it is routinely made by autoclaving brushite to simultaneously sterilize and phase convert. In this study, monetite disc-shaped grafts are produced by both wet and dry heating methods which alter their physical properties such as porosity, surface area, and mechanical strength. Histological observations after 12 weeks of onlay grafting on rabbit calvaria reveal higher bone volume (38%) in autoclaved monetite grafts in comparison with the dry heated monetite grafts (26%). The vertical bone height gained is similar for both the types of monetite grafts (up to 3.2 mm). However, it is observed that the augmented bone height is greater in the lateral than the medial areas of both types of monetite grafts. It is also noted that the higher porosity of autoclaved monetite grafts increases the bioresorbability, whereas the dry heated monetite grafts having lower porosity but higher surface area resorb to a significantly lesser extent. This study provides information regarding two types of monetite onlay grafts prepared with different physical properties that can be further investigated for clinical vertical bone augmentation applications. PMID:27214877

  15. Experimental investigation of control/display augmentation effects in a compensatory tracking task

    NASA Technical Reports Server (NTRS)

    Garg, Sanjay; Schmidt, David K.

    1988-01-01

    The effects of control/display augmentation on human performance and workload have been investigated for closed-loop, continuous-tracking tasks by a real-time, man-in-the-loop simulation study. The experimental results obtained indicate that only limited improvement in actual tracking performance is obtainable through display augmentation alone; with a very high level of display augmentation, tracking error will actually deteriorate. Tracking performance improves when status information is furnished for reasonable levels of display quickening; again, very high quickening levels lead to tracking error deterioration due to the incompatibility between the status information and the quickened signal.

  16. Multimodal user input to supervisory control systems - Voice-augmented keyboard

    NASA Technical Reports Server (NTRS)

    Mitchell, Christine M.; Forren, Michelle G.

    1987-01-01

    The use of a voice-augmented keyboard input modality is evaluated in a supervisory control application. An implementation of voice recognition technology in supervisory control is proposed: voice is used to request display pages, while the keyboard is used to input system reconfiguration commands. Twenty participants controlled GT-MSOCC, a high-fidelity simulation of the operator interface to a NASA ground control system, via a workstation equipped with either a single keyboard or a voice-augmented keyboard. Experimental results showed that in all cases where significant performance differences occurred, performance with the voice-augmented keyboard modality was inferior to and had greater variance than the keyboard-only modality. These results suggest that current moderately priced voice recognition systems are an inappropriate human-computer interaction technology in supervisory control systems.

  17. Prediction of the Chemoreflex Gain by Common Clinical Variables in Heart Failure

    PubMed Central

    Mirizzi, Gianluca; Giannoni, Alberto; Ripoli, Andrea; Iudice, Giovanni; Bramanti, Francesca; Emdin, Michele; Passino, Claudio

    2016-01-01

    Background Peripheral and central chemoreflex sensitivity, assessed by the hypoxic or hypercapnic ventilatory response (HVR and HCVR, respectively), is enhanced in heart failure (HF) patients, is involved in the pathophysiology of the disease, and is under investigation as a potential therapeutic target. Chemoreflex sensitivity assessment is however demanding and, therefore, not easily applicable in the clinical setting. We aimed at evaluating whether common clinical variables, broadly obtained by routine clinical and instrumental evaluation, could predict increased HVR and HCVR. Methods and results 191 patients with systolic HF (left ventricular ejection fraction—LVEF—<50%) underwent chemoreflex assessment by rebreathing technique to assess HVR and HCVR. All patients underwent clinical and neurohormonal evaluation, comprising: echocardiogram, cardiopulmonary exercise test (CPET), daytime cardiorespiratory monitoring for breathing pattern evaluation. Regarding HVR, multivariate penalized logistic regression, Bayesian Model Averaging (BMA) logistic regression and random forest analysis identified, as predictors, the presence of periodic breathing and increased slope of the relation between ventilation and carbon dioxide production (VE/VCO2) during exercise. Again, the above-mentioned statistical tools identified as HCVR predictors plasma levels of N-terminal fragment of proBNP and VE/VCO2 slope. Conclusions In HF patients, the simple assessment of breathing pattern, alongside with ventilatory efficiency during exercise and natriuretic peptides levels identifies a subset of patients presenting with increased chemoreflex sensitivity to either hypoxia or hypercapnia. PMID:27099934

  18. Flight Test of Composite Model Reference Adaptive Control (CMRAC) Augmentation Using NASA AirSTAR Infrastructure

    NASA Technical Reports Server (NTRS)

    Gregory, Irene M.; Gadient, ROss; Lavretsky, Eugene

    2011-01-01

    This paper presents flight test results of a robust linear baseline controller with and without composite adaptive control augmentation. The flight testing was conducted using the NASA Generic Transport Model as part of the Airborne Subscale Transport Aircraft Research system at NASA Langley Research Center.

  19. Exercise training attenuates chemoreflex-mediated reductions of renal blood flow in heart failure.

    PubMed

    Marcus, Noah J; Pügge, Carolin; Mediratta, Jai; Schiller, Alicia M; Del Rio, Rodrigo; Zucker, Irving H; Schultz, Harold D

    2015-07-15

    In chronic heart failure (CHF), carotid body chemoreceptor (CBC) activity is increased and contributes to increased tonic and hypoxia-evoked elevation in renal sympathetic nerve activity (RSNA). Elevated RSNA and reduced renal perfusion may contribute to development of the cardio-renal syndrome in CHF. Exercise training (EXT) has been shown to abrogate CBC-mediated increases in RSNA in experimental heart failure; however, the effect of EXT on CBC control of renal blood flow (RBF) is undetermined. We hypothesized that CBCs contribute to tonic reductions in RBF in CHF, that stimulation of the CBC with hypoxia would result in exaggerated reductions in RBF, and that these responses would be attenuated with EXT. RBF was measured in CHF-sedentary (SED), CHF-EXT, CHF-carotid body denervation (CBD), and CHF-renal denervation (RDNX) groups. We measured RBF at rest and in response to hypoxia (FiO2 10%). All animals exhibited similar reductions in ejection fraction and fractional shortening as well as increases in ventricular systolic and diastolic volumes. Resting RBF was lower in CHF-SED (29 ± 2 ml/min) than in CHF-EXT animals (46 ± 2 ml/min, P < 0.05) or in CHF-CBD animals (42 ± 6 ml/min, P < 0.05). In CHF-SED, RBF decreased during hypoxia, and this was prevented in CHF-EXT animals. Both CBD and RDNX abolished the RBF response to hypoxia in CHF. Mean arterial pressure increased in response to hypoxia in CHF-SED, but was prevented by EXT, CBD, and RDNX. EXT is effective in attenuating chemoreflex-mediated tonic and hypoxia-evoked reductions in RBF in CHF. PMID:26001414

  20. Development and flight evaluation of an augmented stability active controls concept with a small tail

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Parasite drag reduction evaluation is composed of wind tunnel tests with a standard L-1011 tail and two reduced area tail configurations. Trim drag reduction is evaluated by rebalancing the airplane for relaxed static stability. This is accomplished by pumping water to tanks in the forward and aft of the airplane to acheive desired center of gravity location. Also, the L-1011 is modified to incorporate term and advanced augmented systems. By using advanced wings and aircraft relaxed static stability significant fuel savings can be realized. An airplane's dynamic stability becomes more sensitive for decreased tail size, relaxed static stability, and advanced wing configurations. Active control pitch augmentation will be used to acheive the required handling qualities. Flight tests will be performed to evaluate the pitch augmentation systems. The effect of elevator downrig on stabilizer/elevator hinge moments will be measured. For control system analysis, the normal acceleration feedback and pitch rate feedback are analyzed.

  1. Training augmentation device for the Air Force satellite Control Network

    NASA Technical Reports Server (NTRS)

    Shoates, Keith B.

    1993-01-01

    From the 1960's and into the early 1980's satellite operations and control were conducted by Air Force Systems Command (AFSC), now Air Force Materiel Command (AFMC), out of the Satellite Control Facility at Onizuka AFB, CA. AFSC was responsible for acquiring satellite command and control systems and conducting routine satellite operations. The daily operations, consisting of satellite health and status contacts and station keeping activities, were performed for AFSC by a Mission Control Team (MCT) staffed by civilian contractors who were responsible for providing their own technically 'qualified' personnel as satellite operators. An MCT consists of five positions: mission planner, ground controller, planner analyst, orbit analyst, and ranger controller. Most of the training consisted of On-the-Job-Training (OJT) with junior personnel apprenticed to senior personnel until they could demonstrate job proficiency. With most of the satellite operators having 15 to 25 years of experience, there was minimal risk to the mission. In the mid 1980's Air Force Space Command (AFSPACOM) assumed operational responsibility for a newly established control node at Falcon AFB (FAFB) in CO. The satellites and ground system program offices (SPO's) are organized under AFSC's Space and Missiles Systems Center (SMC) to function as a systems engineering and acquisition agency for AFSPACECOM. The collection of the satellite control nodes, ground tracking stations, computer processing equipment, and connecting communications links is referred to as the Air Force Satellite Control Network (AFSCN).

  2. Satellite Dynamic Damping via Active Force Control Augmentation

    NASA Astrophysics Data System (ADS)

    Varatharajoo, Renuganth

    2012-07-01

    An approach that incorporates the Active Force Control (AFC) technique into a conventional Proportional-Derivative (PD) controller is proposed for a satellite active dynamic damping towards a full attitude control. The AFC method has been established to facilitate a robust motion control of dynamical systems in the presence of disturbances, parametric uncertainties and changes that are commonly prevalent in the real-world environment. The usefulness of the method can be extended by introducing intelligent mechanisms to approximate the mass or inertia matrix of the dynamic system to trigger the compensation effect of the controller. AFC is a technique that relies on the appropriate estimation of the inertial or mass parameters of the dynamic system and the measurements of the acceleration and force signals induced by the system if practical implementation is ever considered. In AFC, it is shown that the system subjected to a number of disturbances remains stable and robust via the compensating action of the control strategy. We demonstrate that it is possible to design a spacecraft attitude feedback controller that will ensure the system dynamics set point remains unchanged even in the presence of the disturbances provided that the actual disturbances can be modeled effectively. In order to further facilitate this analysis, a combined energy and attitude control system (CEACS) is proposed as a model satellite attitude control actuator. All the governing equations are established and the proposed satellite attitude control architecture is made amenable to numerical treatments. The results show that the PD-AFC attitude damping performances are superiorly better than that of the solely PD type. It is also shown that the tunings of the AFC system gains are crucial to ensure a better attitude damping performance and this process is mandatory for AFC systems. Finally, the results demonstrate an important satellite dynamic damping enhancement capability using the AFC

  3. Control augmented structural synthesis with dynamic stability constraints

    NASA Technical Reports Server (NTRS)

    Thomas, H. L.; Schmit, L. A., Jr.

    1989-01-01

    Dynamic stability constraints are included in a computer program that simultaneously synthesizes a structure and its control system. Two measures of stability, the real part of the system complex eigenvalues and the damping ratio, are examined. The procedure for calculating the sensitivities of the two measures of stability to changes in the structure and its control system is explained. The sensitivities are used to formulate an approximate problem that is solved at each design iteration. The effects of structural damping and noncollated controllers on the synthesis process are discussed.

  4. A remotely augmented vehicle approach to flight testing RPV control systems

    NASA Technical Reports Server (NTRS)

    Deets, D. A.; Edwards, J. W.

    1974-01-01

    A remotely augmented vehicle concept for flight testing advanced control systems was developed as an outgrowth of a remotely piloted research vehicle (RPV) program in which control laws are implemented through telemetry uplink and downlink data channels using a general purpose ground based digital computer which provides the control law computations. Some advantages of this approach are that the cost of one control system facility is spread over a number of RPV programs, and control laws can be changed quickly as required, without changing the flight hardware. The remotely augmented vehicle concept is described, and flight test results from a subscale F-15 program are discussed. Suggestions of how the concept could lead to more effective testing of RPV control system concepts, and how it is applicable to a military RPV reconnaissance mission are given.

  5. Feedback linearisation control of an induction machine augmented by single-hidden layer neural networks

    NASA Astrophysics Data System (ADS)

    Ait Abbas, Hamou; Belkheiri, Mohammed; Zegnini, Boubakeur

    2016-01-01

    We consider adaptive output feedback control methodology of highly uncertain nonlinear systems with both parametric uncertainties and unmodelled dynamics. The approach is also applicable to systems of unknown, but bounded dimension. However, the relative degree of the regulated output is assumed to be known. This new control strategy is proposed to address the tracking problem of an induction motor based on a modified field-oriented control method. The obtained controller is then augmented by an online neural network that serves as an approximator for the neglected dynamics and modelling errors. The network weight adaptation rule is derived from the Lyapunov stability analysis, that guarantees boundedness of all the error signals of the closed-loop system. Computer simulations of an output feedback controlled induction machine, augmented via single-hidden-layer neural networks, demonstrate the practical potential of the proposed control algorithm.

  6. How to reduce workload--augmented reality to ease the work of air traffic controllers.

    PubMed

    Hofmann, Thomas; König, Christina; Bruder, Ralph; Bergner, Jörg

    2012-01-01

    In the future the air traffic will rise--the workload of the controllers will do the same. In the BMWi research project, one of the tasks is, how to ensure safe air traffic, and a reasonable workload for the air traffic controllers. In this project it was the goal to find ways how to reduce the workload (and stress) for the controllers to allow safe air traffic, esp. at huge hub-airports by implementing augmented reality visualization and interaction. PMID:22316878

  7. Mass-rearing Bemisia parasitoids for support of classical and augmentative biological control programs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The development of efficient mass-rearing systems for Bemisia parasitoids was crucial for the implementation of the classical and augmentative biological control programs for this exotic pest. Early work relied on adapting methods for the production of Encarsia formosa (Gahan) for the greenhouse whi...

  8. Augmentative biological control: research and methods to help make it work

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The essence of augmentative biological control is to repeatedly release an appropriate number of effective natural enemies into a particular place. In practice, especially in field situations, this is complex and faces challenges such as enemy dispersal, pest refugia and deleterious interactions wit...

  9. Analysis of Aeroheating Augmentation due to Reaction Control System Jets on Orion Crew Exploration Vehicle

    NASA Technical Reports Server (NTRS)

    Dyakonov, Artem A.; Buck, Gregory M.; Decaro, Anthony D.

    2009-01-01

    The analysis of effects of the reaction control system jet plumes on aftbody heating of Orion entry capsule is presented. The analysis covered hypersonic continuum part of the entry trajectory. Aerothermal environments at flight conditions were evaluated using Langley Aerothermal Upwind Relaxation Algorithm (LAURA) code and Data Parallel Line Relaxation (DPLR) algorithm code. Results show a marked augmentation of aftbody heating due to roll, yaw and aft pitch thrusters. No significant augmentation is expected due to forward pitch thrusters. Of the conditions surveyed the maximum heat rate on the aftshell is expected when firing a pair of roll thrusters at a maximum deceleration condition.

  10. Global sensitivity analysis in control-augmented structural synthesis

    NASA Technical Reports Server (NTRS)

    Bloebaum, Christina L.

    1989-01-01

    In this paper, an integrated approach to structural/control design is proposed in which variables in both the passive (structural) and active (control) disciplines of an optimization process are changed simultaneously. The global sensitivity equation (GSE) method of Sobieszczanski-Sobieski (1988) is used to obtain the behavior sensitivity derivatives necessary for the linear approximations used in the parallel multidisciplinary synthesis problem. The GSE allows for the decoupling of large systems into smaller subsystems and thus makes it possible to determine the local sensitivities of each subsystem's outputs to its inputs and parameters. The advantages in using the GSE method are demonstrated using a finite-element representation of a truss structure equipped with active lateral displacement controllers, which is undergoing forced vibration.

  11. Optimal placement of active elements in control augmented structural synthesis

    NASA Technical Reports Server (NTRS)

    Sepulveda, A. E.; Jin, I. M.; Schmit, L. A., Jr.

    1992-01-01

    A methodology for structural/control synthesis is presented in which the optimal location of active members is treated in terms of (0,1) variables. Structural member sizes, control gains and (0,1) placement variables are treated simultaneously as design variables. Optimization is carried out by generating and solving a sequence of explicit approximate problems using a branch and bound strategy. Intermediate design variable and intermediate response quantity concepts are used to enhance the quality of the approximate design problems. Numerical results for example problems are presented to illustrate the efficacy of the design procedure set forth.

  12. Augmenting the efficacy of fungal and mycotoxin control via chemosensitization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antimycotic chemosensitization could serve as an effective method for control of fungal pathogens. In a chemo-biological platform to enhance antimycotic susceptibility of fungi or to overcome fungal tolerance to conventional antimycotic agents, the model yeast S. cerevisiae could be a functional too...

  13. Stability Assessment and Tuning of an Adaptively Augmented Classical Controller for Launch Vehicle Flight Control

    NASA Technical Reports Server (NTRS)

    VanZwieten, Tannen; Zhu, J. Jim; Adami, Tony; Berry, Kyle; Grammar, Alex; Orr, Jeb S.; Best, Eric A.

    2014-01-01

    Recently, a robust and practical adaptive control scheme for launch vehicles [ [1] has been introduced. It augments a classical controller with a real-time loop-gain adaptation, and it is therefore called Adaptive Augmentation Control (AAC). The loop-gain will be increased from the nominal design when the tracking error between the (filtered) output and the (filtered) command trajectory is large; whereas it will be decreased when excitation of flex or sloshing modes are detected. There is a need to determine the range and rate of the loop-gain adaptation in order to retain (exponential) stability, which is critical in vehicle operation, and to develop some theoretically based heuristic tuning methods for the adaptive law gain parameters. The classical launch vehicle flight controller design technics are based on gain-scheduling, whereby the launch vehicle dynamics model is linearized at selected operating points along the nominal tracking command trajectory, and Linear Time-Invariant (LTI) controller design techniques are employed to ensure asymptotic stability of the tracking error dynamics, typically by meeting some prescribed Gain Margin (GM) and Phase Margin (PM) specifications. The controller gains at the design points are then scheduled, tuned and sometimes interpolated to achieve good performance and stability robustness under external disturbances (e.g. winds) and structural perturbations (e.g. vehicle modeling errors). While the GM does give a bound for loop-gain variation without losing stability, it is for constant dispersions of the loop-gain because the GM is based on frequency-domain analysis, which is applicable only for LTI systems. The real-time adaptive loop-gain variation of the AAC effectively renders the closed-loop system a time-varying system, for which it is well-known that the LTI system stability criterion is neither necessary nor sufficient when applying to a Linear Time-Varying (LTV) system in a frozen-time fashion. Therefore, a

  14. Leading edge flap system for aircraft control augmentation

    NASA Technical Reports Server (NTRS)

    Rao, D. M. (Inventor)

    1984-01-01

    Traditional roll control systems such as ailerons, elevons or spoilers are least effective at high angles of attack due to boundary layer separation over the wing. This invention uses independently deployed leading edge flaps on the upper surfaces of vortex stabilized wings to shift the center of lift outboard. A rolling moment is created that is used to control roll in flight at high angles of attack. The effectiveness of the rolling moment increases linearly with angle of attack. No adverse yaw effects are induced. In an alternate mode of operation, both leading edge flaps are deployed together at cruise speeds to create a very effective airbrake without appreciable modification in pitching moment. Little trim change is required.

  15. Wearable computer for mobile augmented-reality-based controlling of an intelligent robot

    NASA Astrophysics Data System (ADS)

    Turunen, Tuukka; Roening, Juha; Ahola, Sami; Pyssysalo, Tino

    2000-10-01

    An intelligent robot can be utilized to perform tasks that are either hazardous or unpleasant for humans. Such tasks include working in disaster areas or conditions that are, for example, too hot. An intelligent robot can work on its own to some extent, but in some cases the aid of humans will be needed. This requires means for controlling the robot from somewhere else, i.e. teleoperation. Mobile augmented reality can be utilized as a user interface to the environment, as it enhances the user's perception of the situation compared to other interfacing methods and allows the user to perform other tasks while controlling the intelligent robot. Augmented reality is a method that combines virtual objects into the user's perception of the real world. As computer technology evolves, it is possible to build very small devices that have sufficient capabilities for augmented reality applications. We have evaluated the existing wearable computers and mobile augmented reality systems to build a prototype of a future mobile terminal- the CyPhone. A wearable computer with sufficient system resources for applications, wireless communication media with sufficient throughput and enough interfaces for peripherals has been built at the University of Oulu. It is self-sustained in energy, with enough operating time for the applications to be useful, and uses accurate positioning systems.

  16. Launch Vehicle Manual Steering with Adaptive Augmenting Control In-flight Evaluations Using a Piloted Aircraft

    NASA Technical Reports Server (NTRS)

    Hanson, Curt

    2014-01-01

    An adaptive augmenting control algorithm for the Space Launch System has been developed at the Marshall Space Flight Center as part of the launch vehicles baseline flight control system. A prototype version of the SLS flight control software was hosted on a piloted aircraft at the Armstrong Flight Research Center to demonstrate the adaptive controller on a full-scale realistic application in a relevant flight environment. Concerns regarding adverse interactions between the adaptive controller and a proposed manual steering mode were investigated by giving the pilot trajectory deviation cues and pitch rate command authority.

  17. An analysis of a candidate control algorithm for a ride quality augmentation system

    NASA Technical Reports Server (NTRS)

    Suikat, Reiner; Donaldson, Kent; Downing, David R.

    1987-01-01

    This paper presents a detailed analysis of a candidate algorithm for a ride quality augmentation system. The algorithm consists of a full-state feedback control law based on optimal control output weighting, estimators for angle of attack and sideslip, and a maneuvering algorithm. The control law is shown to perform well by both frequency and time domain analysis. The rms vertical acceleration is reduced by about 40 percent over the whole mission flight envelope. The estimators for the angle of attack and sideslip avoid the often inaccurate or costly direct measurement of those angles. The maneuvering algorithm will allow the augmented airplane to respond to pilot inputs. The design characteristics and performance are documented by the closed-loop eigenvalues; rms levels of vertical, lateral, and longitudinal acceleration; and representative time histories and frequency response.

  18. Simulator investigations of side-stick controller/stability and control augmentation systems for night nap-of-earth flight

    NASA Technical Reports Server (NTRS)

    Landis, K. H.; Aiken, E. W.

    1984-01-01

    Several night nap-of-the-earth mission tasks were evaluated using a helmet-mounted display which provided a limited field-of-view image with superimposed flight control symbology. A wide range of stability and control augmentation designs was investigated. Variations in controller force-deflection characteristics and the number of axes controlled through an integrated side-stick controller were studied. In general, a small displacement controller is preferred over a stiffstick controller particularly for maneuvering flight. Higher levels of stability augmentation were required for IMC tasks to provide handling qualities comparable to those achieved for the same tasks conducted under simulated visual flight conditions. Previously announced in STAR as N82-23216

  19. Reconfigurable Control with Neural Network Augmentation for a Modified F-15 Aircraft

    NASA Technical Reports Server (NTRS)

    Burken, John J.; Williams-Hayes, Peggy; Kaneshige, John T.; Stachowiak, Susan J.

    2006-01-01

    Description of the performance of a simplified dynamic inversion controller with neural network augmentation follows. Simulation studies focus on the results with and without neural network adaptation through the use of an F-15 aircraft simulator that has been modified to include canards. Simulated control law performance with a surface failure, in addition to an aerodynamic failure, is presented. The aircraft, with adaptation, attempts to minimize the inertial cross-coupling effect of the failure (a control derivative anomaly associated with a jammed control surface). The dynamic inversion controller calculates necessary surface commands to achieve desired rates. The dynamic inversion controller uses approximate short period and roll axis dynamics. The yaw axis controller is a sideslip rate command system. Methods are described to reduce the cross-coupling effect and maintain adequate tracking errors for control surface failures. The aerodynamic failure destabilizes the pitching moment due to angle of attack. The results show that control of the aircraft with the neural networks is easier (more damped) than without the neural networks. Simulation results show neural network augmentation of the controller improves performance with aerodynamic and control surface failures in terms of tracking error and cross-coupling reduction.

  20. Adaptive Control Using Neural Network Augmentation for a Modified F-15 Aircraft

    NASA Technical Reports Server (NTRS)

    Burken, John J.; Williams-Hayes, Peggy; Karneshige, J. T.; Stachowiak, Susan J.

    2006-01-01

    Description of the performance of a simplified dynamic inversion controller with neural network augmentation follows. Simulation studies focus on the results with and without neural network adaptation through the use of an F-15 aircraft simulator that has been modified to include canards. Simulated control law performance with a surface failure, in addition to an aerodynamic failure, is presented. The aircraft, with adaptation, attempts to minimize the inertial cross-coupling effect of the failure (a control derivative anomaly associated with a jammed control surface). The dynamic inversion controller calculates necessary surface commands to achieve desired rates. The dynamic inversion controller uses approximate short period and roll axis dynamics. The yaw axis controller is a sideslip rate command system. Methods are described to reduce the cross-coupling effect and maintain adequate tracking errors for control surface failures. The aerodynamic failure destabilizes the pitching moment due to angle of attack. The results show that control of the aircraft with the neural networks is easier (more damped) than without the neural networks. Simulation results show neural network augmentation of the controller improves performance with aerodynamic and control surface failures in terms of tracking error and cross-coupling reduction.

  1. Sliding mode control for Lorentz-augmented spacecraft hovering around elliptic orbits

    NASA Astrophysics Data System (ADS)

    Huang, Xu; Yan, Ye; Zhou, Yang; Zhang, Hua

    2014-10-01

    A Lorentz spacecraft is an electrostatically charged space vehicle that could actively modulate its surface charge to generate Lorentz force as it moves through the planetary magnetic field. The induced Lorentz force provides propellantless electromagnetic propulsion for orbital maneuvering, such as spacecraft hovering that the chaser thrusts continuously to create an equilibrium state at the desired position relative to the target. Due to the fact that the direction of Lorentz force is determined by the local magnetic field and the velocity of the spacecraft with respect to the local magnetic field, which does not necessarily coincide with that of the required control acceleration for hovering, thus, in most cases, the Lorentz force works as a means of auxiliary propulsion to reduce the expenditure of fuel onboard. And that is why it is called Lorentz-augmented hovering. A dynamical model for Lorentz-augmented hovering around elliptic orbits is developed based upon the assumption that the Earth's magnetic field could be modeled as a tilted dipole that corotates with Earth. Fuel-optimal open-loop control laws are then derived based on the proposed dynamical model, presenting the optimal trajectories of the required specific charge of Lorentz spacecraft and the thruster-generated control acceleration. Considering the external disturbances that may drift the desired hovering position, a closed-loop integral sliding mode controller is also designed to guarantee the tracking of optimal control trajectories, ensuring the robustness of the system against perturbations. Numerical simulations are presented to analyze the characteristics of Lorentz-augmented hovering around eccentric orbits and the results substantiate the validity of the proposed open-loop and closed-loop control methods.

  2. Effect of continuous rearing on courtship acoustics of five braconid parasitoids, candidates for augmentative biological control of Anastrepha species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The courtship acoustics of five species of parasitoid wasps (Hymenoptera: Braconidae), potential candidates for augmentative biological control of Anastrepha species (Diptera: Tephritidae), were compared between recently colonized individuals and those continuously reared 70-148 generations. During...

  3. Launch vehicle flight control augmentation using smart materials and advanced composites (CDDF Project 93-05)

    NASA Technical Reports Server (NTRS)

    Barret, C.

    1995-01-01

    The Marshall Space Flight Center has a rich heritage of launch vehicles that have used aerodynamic surfaces for flight stability such as the Saturn vehicles and flight control such as on the Redstone. Recently, due to aft center-of-gravity locations on launch vehicles currently being studied, the need has arisen for the vehicle control augmentation that is provided by these flight controls. Aerodynamic flight control can also reduce engine gimbaling requirements, provide actuator failure protection, enhance crew safety, and increase vehicle reliability, and payload capability. In the Saturn era, NASA went to the Moon with 300 sq ft of aerodynamic surfaces on the Saturn V. Since those days, the wealth of smart materials and advanced composites that have been developed allow for the design of very lightweight, strong, and innovative launch vehicle flight control surfaces. This paper presents an overview of the advanced composites and smart materials that are directly applicable to launch vehicle control surfaces.

  4. A control-volume method for analysis of unsteady thrust augmenting ejector flows

    NASA Technical Reports Server (NTRS)

    Drummond, Colin K.

    1988-01-01

    A method for predicting transient thrust augmenting ejector characteristics is presented. The analysis blends classic self-similar turbulent jet descriptions with a control volume mixing region discretization to solicit transient effects in a new way. Division of the ejector into an inlet, diffuser, and mixing region corresponds with the assumption of viscous-dominated phenomenon in the latter. Inlet and diffuser analyses are simplified by a quasi-steady analysis, justified by the assumptions that pressure is the forcing function in those regions. Details of the theoretical foundation, the solution algorithm, and sample calculations are given.

  5. Optimal placement of actuators and sensors in control augmented structural optimization

    NASA Technical Reports Server (NTRS)

    Sepulveda, A. E.; Schmit, L. A., Jr.

    1990-01-01

    A control-augmented structural synthesis methodology is presented in which actuator and sensor placement is treated in terms of (0,1) variables. Structural member sizes and control variables are treated simultaneously as design variables. A multiobjective utopian approach is used to obtain a compromise solution for inherently conflicting objective functions such as strucutal mass control effort and number of actuators. Constraints are imposed on transient displacements, natural frequencies, actuator forces and dynamic stability as well as controllability and observability of the system. The combinatorial aspects of the mixed - (0,1) continuous variable design optimization problem are made tractable by combining approximation concepts with branch and bound techniques. Some numerical results for example problems are presented to illustrate the efficacy of the design procedure set forth.

  6. Effectiveness of basic display augmentation in vehicular control by visual field cues

    NASA Technical Reports Server (NTRS)

    Grunwald, A. J.; Merhav, S. J.

    1978-01-01

    The paper investigates the effectiveness of different basic display augmentation concepts - fixed reticle, velocity vector, and predicted future vehicle path - for RPVs controlled by a vehicle-mounted TV camera. The task is lateral manual control of a low flying RPV along a straight reference line in the presence of random side gusts. The man-machine system and the visual interface are modeled as a linear time-invariant system. Minimization of a quadratic performance criterion is assumed to underlie the control strategy of a well-trained human operator. The solution for the optimal feedback matrix enables the explicit computation of the variances of lateral deviation and directional error of the vehicle and of the control force that are used as performance measures.

  7. The myths and physiology surrounding intrapartum decelerations: the critical role of the peripheral chemoreflex.

    PubMed

    Lear, Christopher A; Galinsky, Robert; Wassink, Guido; Yamaguchi, Kyohei; Davidson, Joanne O; Westgate, Jenny A; Bennet, Laura; Gunn, Alistair J

    2016-09-01

    A distinctive pattern of recurrent rapid falls in fetal heart rate, called decelerations, are commonly associated with uterine contractions during labour. These brief decelerations are mediated by vagal activation. The reflex triggering this vagal response has been variably attributed to a mechanoreceptor response to fetal head compression, to baroreflex activation following increased blood pressure during umbilical cord compression, and/or a Bezold-Jarisch reflex response to reduced venous return from the placenta. Although these complex explanations are still widespread today, there is no consistent evidence that they are common during labour. Instead, the only mechanism that has been systematically investigated, proven to be reliably active during labour and, crucially, capable of producing rapid decelerations is the peripheral chemoreflex. The peripheral chemoreflex is triggered by transient periods of asphyxia that are a normal phenomenon associated with all uterine contractions. This should not cause concern as the healthy fetus has a remarkable ability to adapt to these repeated but short periods of asphyxia. This means that the healthy fetus is typically not at risk of hypotension and injury during uncomplicated labour even during repeated brief decelerations. The physiologically incorrect theories surrounding decelerations that ignore the natural occurrence of repeated asphyxia probably gained widespread support to help explain why many babies are born healthy despite repeated decelerations during labour. We propose that a unified and physiological understanding of intrapartum decelerations that accepts the true nature of labour is critical to improve interpretation of intrapartum fetal heart rate patterns. PMID:27328617

  8. Autonomic and cardiovascular responses to chemoreflex stress in apnoea divers.

    PubMed

    Steinback, Craig D; Breskovic, Toni; Banic, Ivana; Dujic, Zeljko; Shoemaker, J Kevin

    2010-08-25

    Sleep apnoea, with repeated periods of hypoxia, results in cardiovascular morbidity and concomitant autonomic dysregulation. Trained apnoea divers also perform prolonged apnoeas accompanied by large lung volumes, large reductions in cardiac output and severe hypoxia and hypercapnia. We tested the hypothesis that apnoea training would be associated with decreased cardiovagal and sympathetic baroreflex gains and reduced respiratory modulation of muscle sympathetic nerve activity (MSNA; microneurography). Six trained divers and six controls were studied at rest and during asphyxic rebreathing. Despite an elevated resting heart rate (70+/-14 vs. 56+/-10 bpm; p=0.038), divers had a similar cardiovagal baroreflex gain (-1.22+/-0.47 beats/mmHg) as controls (-1.29+/-0.61; NS). Similarly, though MSNA burst frequency was slightly higher in divers at rest (16+/-4 bursts/min vs. 10+/-5 bursts/min, p=0.03) there was no difference in baseline burst incidence, sympathetic baroreflex gain (-3.8+/-2.1%/mmHg vs. -4.7+/-1.7%/mmHg) or respiratory modulation of MSNA between groups. Resting total peripheral resistance (11.9+/-2.6 vs. 12.3+/-2.2 mmHg/L/min) and pulse wave velocity (5.82+/-0.55 vs. 6.10+/-0.51 m/s) also were similar between divers and controls, respectively. Further, the sympathetic response to asphyxic rebreathing was not different between controls and divers (-1.70+/-1.07 vs. -1.74+/-0.84 a.u./% desaturation). Thus, these data suggest that, unlike patients with sleep apnoea, apnoea training in otherwise healthy individuals does not produce detectable autonomic dysregulation or maladaption. PMID:20627720

  9. Development and flight evaluation of active controls in the L-1011. [including wing load alleviation and stability augmentation

    NASA Technical Reports Server (NTRS)

    Johnston, J. F.; Urie, D. M.

    1978-01-01

    Active controls in the Lockheed L-1011 for increased energy efficiency are discussed. Active wing load alleviation for extended span, increased aspect ratio, and active stability augmentation with a smaller tail for reduced drag and weight are among the topics considered. Flight tests of active wing load alleviation on the baseline aircraft and moving-base piloted simulation developing criteria for stability augmentation are described.

  10. Presentation of flight control design and handling quality commonality by separate surface stability augmentation for the family of commuter airplanes

    NASA Technical Reports Server (NTRS)

    Hensley, Douglas; Creighton, Thomas; Haddad, Raphael; Hendrich, Louis; Morgan, Louise; Russell, Mark; Swift, Gerald

    1987-01-01

    The methodology and results for a flight control design and implementation for common handling qualities by Separate Surface Stability Augmentation (SSSA) for the family of commuter airplanes are contained. The open and closed loop dynamics and the design results of augmenting for common handling qualities are presented. The physical and technology requirements are presented for implementing the SSSA system. The conclusion of this report and recommendations for changes or improvement are discussed.

  11. Acrolein Causes TRPA1-Mediated Sensory Irritation and Indirect Potentiation of TRPV1-Mediated Pulmonary Chemoreflex Response

    EPA Science Inventory

    We previously demonstrated that acute exposure to acrolein causes immediate sensory irritation, with rapid decrease in heart rate (HR) and increase in inspiratory time (Ti), and potentiation of pulmonary chemoreflex response 24hrs later; of these effects only the latter is mediat...

  12. Engine Yaw Augmentation for Hybrid-Wing-Body Aircraft via Optimal Control Allocation Techniques

    NASA Technical Reports Server (NTRS)

    Taylor, Brian R.; Yoo, Seung-Yeun

    2011-01-01

    Asymmetric engine thrust was implemented in a hybrid-wing-body non-linear simulation to reduce the amount of aerodynamic surface deflection required for yaw stability and control. Hybrid-wing-body aircraft are especially susceptible to yaw surface deflection due to their decreased bare airframe yaw stability resulting from the lack of a large vertical tail aft of the center of gravity. Reduced surface deflection, especially for trim during cruise flight, could reduce the fuel consumption of future aircraft. Designed as an add-on, optimal control allocation techniques were used to create a control law that tracks total thrust and yaw moment commands with an emphasis on not degrading the baseline system. Implementation of engine yaw augmentation is shown and feasibility is demonstrated in simulation with a potential drag reduction of 2 to 4 percent. Future flight tests are planned to demonstrate feasibility in a flight environment.

  13. Riluzole augmentation in treatment-refractory obsessive-compulsive disorder: a pilot placebo-controlled trial

    PubMed Central

    Pittenger, Christopher; Bloch, Michael H.; Wasylink, Suzanne; Billingslea, Eileen; Simpson, Ryan; Jakubovski, Ewgeni; Kelmendi, Ben; Sanacora, Gerard; Coric, Vladimir

    2015-01-01

    Objective Obsessive-compulsive disorder (OCD) affects approximately 2.5% of the population and is associated with significant morbidity. Many patients receive little benefit from the best available treatments, and even those who do respond often suffer from significant residual symptoms. Convergent evidence suggests that abnormalities in glutamate homeostasis and neurotransmission may contribute to OCD and that glutamate-modulating medications may be of benefit in patients whose symptoms are refractory to standard interventions. Small open-label trials of augmentation of SSRI pharmacotherapy with the glutamate modulator riluzole have suggested benefit in adults with refractory symptoms. We report a pilot placebo-control trial of riluzole augmentation of ongoing SRI treatment in SRI-refractory patients. Method Outpatients (n = 27) and inpatients (n = 12) with DSM-IV OCD on stable SSRI pharmacotherapy were randomized between 11/2006 and 12/2012 to receive riluzole 50 mg bid or placebo and followed for 12 weeks, after a 2-week placebo lead-in. Results Riluzole was well tolerated; one patient experienced moderate nausea, but none discontinued treatment due to side effects. While there was nominally greater Y-BOCS improvement in the riluzole group (our primary outcome), it did not reach significance in a mixed model random effects analysis, in the overall analysis or in the outpatient subsample. In the outpatient subsample there was a trend suggesting benefit from riluzole augmentation for obsessions (p = 0.056, 2-tailed, uncorrected), in a secondary analysis. Among outpatients, more achieved at least a partial response (>25% improvement) with riluzole than with placebo (p = 0.02 in a secondary analysis). Conclusions Riluzole may be of benefit to a subset of patients. Larger samples would be required to detect effects of the order suggested by the nominal improvement in our outpatient subsample. PMID:26214725

  14. The Roles of Parasitoid Foraging for Hosts, Food and Mates in the Augmentative Control of Tephritidae

    PubMed Central

    Sivinski, John; Aluja, Martin

    2012-01-01

    Ultimately, the success of augmentative fruit fly biological control depends upon the survival, dispersal, attack rate and multi-generational persistence of mass-reared parasitoids in the field. Foraging for hosts, food and mates is fundamental to the above and, at an operational level, the choice of the parasitoid best suited to control a particular tephritid in a certain environment, release rate estimates and subsequent monitoring of effectiveness. In the following we review landscape-level and microhabitat foraging preferences, host/fruit ranges, orientation through environmental cues, host vulnerabilities/ovipositor structures, and inter and intraspecific competition. We also consider tephritid parasitoid mating systems and sexual signals, and suggest the directions of future research. PMID:26466622

  15. Ultrasound guided robotic biopsy using augmented reality and human-robot cooperative control.

    PubMed

    Freschi, C; Troia, E; Ferrari, V; Megali, G; Pietrabissa, A; Mosca, F

    2009-01-01

    Ultrasound-guided biopsy is a proficient mininvasive approach for tumors staging but requires very long training and particular manual and 3D space perception abilities of the physician, for the planning of the needle trajectory and the execution of the procedure. In order to simplify this difficult task, we have developed an integrated system that provides the clinician two types of assistance: an augmented reality visualization allows accurate and easy planning of needle trajectory and target reaching verification; a robot arm with a six-degree-of-freedom force sensor allows the precise positioning of the needle holder and allows the clinician to adjust the planned trajectory (cooperative control) to overcome needle deflection and target motion. Preliminary tests have been executed on an ultrasound phantom showing high precision of the system in static conditions and the utility and usability of the cooperative control in simulated no-rigid conditions. PMID:19963882

  16. The Roles of Parasitoid Foraging for Hosts, Food and Mates in the Augmentative Control of Tephritidae.

    PubMed

    Sivinski, John; Aluja, Martin

    2012-01-01

    Ultimately, the success of augmentative fruit fly biological control depends upon the survival, dispersal, attack rate and multi-generational persistence of mass-reared parasitoids in the field. Foraging for hosts, food and mates is fundamental to the above and, at an operational level, the choice of the parasitoid best suited to control a particular tephritid in a certain environment, release rate estimates and subsequent monitoring of effectiveness. In the following we review landscape-level and microhabitat foraging preferences, host/fruit ranges, orientation through environmental cues, host vulnerabilities/ovipositor structures, and inter and intraspecific competition. We also consider tephritid parasitoid mating systems and sexual signals, and suggest the directions of future research. PMID:26466622

  17. Stereovision and augmented reality for closed-loop control of grasping in hand prostheses

    NASA Astrophysics Data System (ADS)

    Markovic, Marko; Dosen, Strahinja; Cipriani, Christian; Popovic, Dejan; Farina, Dario

    2014-08-01

    Objective. Technologically advanced assistive devices are nowadays available to restore grasping, but effective and effortless control integrating both feed-forward (commands) and feedback (sensory information) is still missing. The goal of this work was to develop a user friendly interface for the semi-automatic and closed-loop control of grasping and to test its feasibility. Approach. We developed a controller based on stereovision to automatically select grasp type and size and augmented reality (AR) to provide artificial proprioceptive feedback. The system was experimentally tested in healthy subjects using a dexterous hand prosthesis to grasp a set of daily objects. The subjects wore AR glasses with an integrated stereo-camera pair, and triggered the system via a simple myoelectric interface. Main results. The results demonstrated that the subjects got easily acquainted with the semi-autonomous control. The stereovision grasp decoder successfully estimated the grasp type and size in realistic, cluttered environments. When allowed (forced) to correct the automatic system decisions, the subjects successfully utilized the AR feedback and achieved close to ideal system performance. Significance. The new method implements a high level, low effort control of complex functions in addition to the low level closed-loop control. The latter is achieved by providing rich visual feedback, which is integrated into the real life environment. The proposed system is an effective interface applicable with small alterations for many advanced prosthetic and orthotic/therapeutic rehabilitation devices.

  18. An assessment of various side-stick controller/stability and control augmentation systems for night nap-of-Earth flight using piloted simulation

    NASA Technical Reports Server (NTRS)

    Landis, K. H.; Aiken, E. W.

    1982-01-01

    Several night nap-of-the-earth mission tasks were evaluated using a helmet-mounted display which provided a limited field-of-view image with superimposed flight control symbology. A wide range of stability and control augmentation designs was investigated. Variations in controller force-deflection characteristics and the number of axes controlled through an integrated side-stick controller were studied. In general, a small displacement controller is preferred over a stiffstick controller particularly for maneuvering flight. Higher levels of stability augmentation were required for IMC tasks to provide handling qualities comparable to those achieved for the same tasks conducted under simulated visual flight conditions.

  19. Analysis and testing of stability augmentation systems. [for supersonic transport aircraft wing and B-52 aircraft control system

    NASA Technical Reports Server (NTRS)

    Sevart, F. D.; Patel, S. M.; Wattman, W. J.

    1972-01-01

    Testing and evaluation of stability augmentation systems for aircraft flight control were conducted. The flutter suppression system analysis of a scale supersonic transport wing model is described. Mechanization of the flutter suppression system is reported. The ride control synthesis for the B-52 aeroelastic model is discussed. Model analyses were conducted using equations of motion generated from generalized mass and stiffness data.

  20. Sympathetic neural recruitment strategies: responses to severe chemoreflex and baroreflex stress

    PubMed Central

    Badrov, Mark B.; Usselman, Charlotte W.

    2015-01-01

    This study tested the hypothesis that neural coding patterns exist within the autonomic nervous system. We investigated sympathetic axonal recruitment strategies in humans during chemoreflex- and baroreflex-mediated sympathoexcitation using a novel action potential (AP) analysis technique. Muscle sympathetic nerve activity (microneurography) was collected in 11 young individuals (6 females) during baseline and two subsequent protocols: 1) severe chemoreflex stimulation (maximal end-inspiratory apnea following rebreathe), and 2) severe baroreceptor unloading (−80 mmHg lower body negative pressure; LBNP). When compared with each respective baseline, apnea and LBNP increased AP frequency and mean AP content per sympathetic burst (all P < 0.01). When APs were binned according to peak-to-peak amplitude (i.e., into “clusters”), total clusters detected increased during both apnea (Δ7 ± 5; P = 0.0009) and LBNP (Δ11 ± 8; P = 0.0012) compared with baseline. This was concomitant to an increased number of active clusters per burst during apnea (Δ3 ± 1; P < 0.0001) and LBNP (Δ3 ± 3; P = 0.0076). At baseline and during apnea (R2 = 0.98; P < 0.0001) and LBNP (R2 = 0.95; P < 0.0001), a pattern emerged whereby AP cluster latency decreased as cluster size increased. Furthermore, the AP cluster latency profile was shifted downward during apnea (∼53 ms) and upward during LBNP (∼31 ms). The data indicate that variations in synaptic delays and latent subpopulations of larger axons exist as recruitment strategies for sympathetic outflow. The synaptic delay component appears to express reflex specificity, whereas latent subpopulation recruitment demonstrates sensitivity to stress severity. PMID:25947171

  1. Sympathetic neural recruitment strategies: responses to severe chemoreflex and baroreflex stress.

    PubMed

    Badrov, Mark B; Usselman, Charlotte W; Shoemaker, J Kevin

    2015-07-15

    This study tested the hypothesis that neural coding patterns exist within the autonomic nervous system. We investigated sympathetic axonal recruitment strategies in humans during chemoreflex- and baroreflex-mediated sympathoexcitation using a novel action potential (AP) analysis technique. Muscle sympathetic nerve activity (microneurography) was collected in 11 young individuals (6 females) during baseline and two subsequent protocols: 1) severe chemoreflex stimulation (maximal end-inspiratory apnea following rebreathe), and 2) severe baroreceptor unloading (-80 mmHg lower body negative pressure; LBNP). When compared with each respective baseline, apnea and LBNP increased AP frequency and mean AP content per sympathetic burst (all P < 0.01). When APs were binned according to peak-to-peak amplitude (i.e., into "clusters"), total clusters detected increased during both apnea (Δ7 ± 5; P = 0.0009) and LBNP (Δ11 ± 8; P = 0.0012) compared with baseline. This was concomitant to an increased number of active clusters per burst during apnea (Δ3 ± 1; P < 0.0001) and LBNP (Δ3 ± 3; P = 0.0076). At baseline and during apnea (R(2) = 0.98; P < 0.0001) and LBNP (R(2) = 0.95; P < 0.0001), a pattern emerged whereby AP cluster latency decreased as cluster size increased. Furthermore, the AP cluster latency profile was shifted downward during apnea (∼53 ms) and upward during LBNP (∼31 ms). The data indicate that variations in synaptic delays and latent subpopulations of larger axons exist as recruitment strategies for sympathetic outflow. The synaptic delay component appears to express reflex specificity, whereas latent subpopulation recruitment demonstrates sensitivity to stress severity. PMID:25947171

  2. Interpreting the handling qualities of aircraft with stability and control augmentation

    NASA Technical Reports Server (NTRS)

    Hodgkinson, J.; Potsdam, E. H.; Smith, R. E.

    1990-01-01

    The general process of designing an aircraft for good flying qualities is first discussed. Lessons learned are pointed out, with piloted evaluation emerging as a crucial element. Two sources of rating variability in performing these evaluations are then discussed. First, the finite endpoints of the Cooper-Harper scale do not bias parametric statistical analyses unduly. Second, the wording of the scale does introduce some scatter. Phase lags generated by augmentation systems, as represented by equivalent time delays, often cause poor flying qualities. An analysis is introduced which allows a designer to relate any level of time delay to a probability of loss of aircraft control. This view of time delays should, it is hoped, allow better visibility of the time delays in the design process.

  3. Reconfigurable Control with Neural Network Augmentation for a Modified F-15 Aircraft

    NASA Technical Reports Server (NTRS)

    Burken, John J.

    2007-01-01

    This paper describes the performance of a simplified dynamic inversion controller with neural network supplementation. This 6 DOF (Degree-of-Freedom) simulation study focuses on the results with and without adaptation of neural networks using a simulation of the NASA modified F-15 which has canards. One area of interest is the performance of a simulated surface failure while attempting to minimize the inertial cross coupling effect of a [B] matrix failure (a control derivative anomaly associated with a jammed or missing control surface). Another area of interest and presented is simulated aerodynamic failures ([A] matrix) such as a canard failure. The controller uses explicit models to produce desired angular rate commands. The dynamic inversion calculates the necessary surface commands to achieve the desired rates. The simplified dynamic inversion uses approximate short period and roll axis dynamics. Initial results indicated that the transient response for a [B] matrix failure using a Neural Network (NN) improved the control behavior when compared to not using a neural network for a given failure, However, further evaluation of the controller was comparable, with objections io the cross coupling effects (after changes were made to the controller). This paper describes the methods employed to reduce the cross coupling effect and maintain adequate tracking errors. The IA] matrix failure results show that control of the aircraft without adaptation is more difficult [leas damped) than with active neural networks, Simulation results show Neural Network augmentation of the controller improves performance in terms of backing error and cross coupling reduction and improved performance with aerodynamic-type failures.

  4. Adaptive Augmenting Control Flight Characterization Experiment on an F/A-18

    NASA Technical Reports Server (NTRS)

    VanZwieten, Tannen S.; Gilligan, Eric T.; Wall, John H.; Orr, Jeb S.; Miller, Christopher J.; Hanson, Curtis E.

    2014-01-01

    The NASA Marshall Space Flight Center (MSFC) Flight Mechanics and Analysis Division developed an Adaptive Augmenting Control (AAC) algorithm for launch vehicles that improves robustness and performance by adapting an otherwise welltuned classical control algorithm to unexpected environments or variations in vehicle dynamics. This AAC algorithm is currently part of the baseline design for the SLS Flight Control System (FCS), but prior to this series of research flights it was the only component of the autopilot design that had not been flight tested. The Space Launch System (SLS) flight software prototype, including the adaptive component, was recently tested on a piloted aircraft at Dryden Flight Research Center (DFRC) which has the capability to achieve a high level of dynamic similarity to a launch vehicle. Scenarios for the flight test campaign were designed specifically to evaluate the AAC algorithm to ensure that it is able to achieve the expected performance improvements with no adverse impacts in nominal or nearnominal scenarios. Having completed the recent series of flight characterization experiments on DFRC's F/A-18, the AAC algorithm's capability, robustness, and reproducibility, have been successfully demonstrated. Thus, the entire SLS control architecture has been successfully flight tested in a relevant environment. This has increased NASA's confidence that the autopilot design is ready to fly on the SLS Block I vehicle and will exceed the performance of previous architectures.

  5. Augmenting Psychoeducation with a Mobile Intervention for Bipolar Disorder: A Randomized Controlled Trial

    PubMed Central

    Depp, Colin A; Ceglowski, Jenni; Wang, Vicki C; Yaghouti, Faraz; Mausbach, Brent T; Thompson, Wesley K; Granholm, Eric L

    2014-01-01

    Background Psychosocial interventions for bipolar disorder are frequently unavailable and resource intensive. Mobile technology may improve access to evidence-based interventions and may increase their efficacy. We evaluated the feasibility, acceptability and efficacy of an augmentative mobile ecological momentary intervention targeting self-management of mood symptoms. Methods This was a randomized single-blind controlled trial with 82 consumers diagnosed with bipolar disorder who completed a four-session psychoeducational intervention and were assigned to 10 weeks of either: 1) mobile device delivered interactive intervention linking patient-reported mood states with personalized self-management strategies, or 2) paper-and-pencil mood monitoring. Participants were assessed at baseline, 6 weeks (mid-point), 12 weeks (post-treatment), and 24 weeks (follow up) with clinician-rated depression and mania scales and self-reported functioning. Results Retention at 12 weeks was 93% and both conditions were associated with high satisfaction. Compared to the paper-and-pencil condition, participants in the augmented mobile intervention condition showed significantly greater reductions in depressive symptoms at 6 and 12 weeks (Cohen's d for both were d=0.48). However, these effects were not maintained at 24-week follow up. Conditions did not differ significantly in the impact on manic symptoms or functional impairment. Limitations This was not a definitive trial and was not powered to detect moderators and mediators. Conclusions Automated mobile-phone intervention is feasible, acceptable, and may enhance the impact of brief psychoeducation on depressive symptoms in bipolar disorder. However, sustainment of gains from symptom self-management mobile interventions, once stopped, may be limited. PMID:25479050

  6. Analysis and testing of aeroelastic model stability augmentation systems. [for supersonic transport aircraft wing and B-52 aircraft control system

    NASA Technical Reports Server (NTRS)

    Sevart, F. D.; Patel, S. M.

    1973-01-01

    Testing and evaluation of a stability augmentation system for aircraft flight control were performed. The flutter suppression system and synthesis conducted on a scale model of a supersonic wing for a transport aircraft are discussed. Mechanization and testing of the leading and trailing edge surface actuation systems are described. The ride control system analyses for a 375,000 pound gross weight B-52E aircraft are presented. Analyses of the B-52E aircraft maneuver load control system are included.

  7. In Vivo versus Augmented Reality Exposure in the Treatment of Small Animal Phobia: A Randomized Controlled Trial.

    PubMed

    Botella, Cristina; Pérez-Ara, M Ángeles; Bretón-López, Juana; Quero, Soledad; García-Palacios, Azucena; Baños, Rosa María

    2016-01-01

    Although in vivo exposure is the treatment of choice for specific phobias, some acceptability problems have been associated with it. Virtual Reality exposure has been shown to be as effective as in vivo exposure, and it is widely accepted for the treatment of specific phobias, but only preliminary data are available in the literature about the efficacy of Augmented Reality. The purpose of the present study was to examine the efficacy and acceptance of two treatment conditions for specific phobias in which the exposure component was applied in different ways: In vivo exposure (N = 31) versus an Augmented Reality system (N = 32) in a randomized controlled trial. "One-session treatment" guidelines were followed. Participants in the Augmented Reality condition significantly improved on all the outcome measures at post-treatment and follow-ups. When the two treatment conditions were compared, some differences were found at post-treatment, favoring the participants who received in vivo exposure. However, these differences disappeared at the 3- and 6-month follow-ups. Regarding participants' expectations and satisfaction with the treatment, very positive ratings were reported in both conditions. In addition, participants from in vivo exposure condition considered the treatment more useful for their problem whereas participants from Augmented Reality exposure considered the treatment less aversive. Results obtained in this study indicate that Augmented Reality exposure is an effective treatment for specific phobias and well accepted by the participants. PMID:26886423

  8. In Vivo versus Augmented Reality Exposure in the Treatment of Small Animal Phobia: A Randomized Controlled Trial

    PubMed Central

    Botella, Cristina; Pérez-Ara, M. Ángeles; Bretón-López, Juana; Quero, Soledad; García-Palacios, Azucena; Baños, Rosa María

    2016-01-01

    Although in vivo exposure is the treatment of choice for specific phobias, some acceptability problems have been associated with it. Virtual Reality exposure has been shown to be as effective as in vivo exposure, and it is widely accepted for the treatment of specific phobias, but only preliminary data are available in the literature about the efficacy of Augmented Reality. The purpose of the present study was to examine the efficacy and acceptance of two treatment conditions for specific phobias in which the exposure component was applied in different ways: In vivo exposure (N = 31) versus an Augmented Reality system (N = 32) in a randomized controlled trial. “One-session treatment” guidelines were followed. Participants in the Augmented Reality condition significantly improved on all the outcome measures at post-treatment and follow-ups. When the two treatment conditions were compared, some differences were found at post-treatment, favoring the participants who received in vivo exposure. However, these differences disappeared at the 3- and 6-month follow-ups. Regarding participants’ expectations and satisfaction with the treatment, very positive ratings were reported in both conditions. In addition, participants from in vivo exposure condition considered the treatment more useful for their problem whereas participants from Augmented Reality exposure considered the treatment less aversive. Results obtained in this study indicate that Augmented Reality exposure is an effective treatment for specific phobias and well accepted by the participants. PMID:26886423

  9. Tantalum acetabular augments in one-stage exchange of infected total hip arthroplasty: a case-control study.

    PubMed

    Klatte, Till Orla; Kendoff, Daniel; Sabihi, Reza; Kamath, Atul F; Rueger, Johannes M; Gehrke, Thorsten

    2014-07-01

    During the one-stage exchange procedure for periprosthetic joint infection (PJI) after total hip arthroplasty (THA), acetabular defects challenge reconstructive options. Porous tantalum augments are an established tool for addressing acetabular destruction in aseptic cases, but their utility in septic exchange is unknown. This retrospective case-control study presents the initial results of tantalum augmentation during one-stage exchange for PJI. Primary endpoints were rates of re-infection and short-term complications associated with this technique. Study patients had no higher risk of re-infection with equivalent durability at early follow-up with a re-infection rate in both groups of 4%. In conclusion, tantalum augments are a viable option for addressing acetabular defects in one-stage exchange for septic THA. Further study is necessary to assess long-term durability when compared to traditional techniques for acetabular reconstruction. PMID:24559522

  10. Control of the molecular degradation of hyaluronic acid hydrogels for tissue augmentation.

    PubMed

    Oh, Eun Ju; Kang, Sun-Woong; Kim, Byung-Soo; Jiang, Ge; Cho, Il Hwan; Hahn, Sei Kwang

    2008-09-01

    A novel protocol to control the molecular degradation of hyaluronic acid (HA) hydrogels was successfully developed for tissue augmentation applications. HA has a different conformational structure in water and organic solvent, and the carboxyl group of HA is known to be the recognition site of hyaluronidase and HA receptors. Based on these findings, HA was chemically modified by grafting adipic acid dihydrazide (ADH) to the carboxyl group of HA in the water to prepare HA-ADH(WATER) and in the mixed solvent of water and ethanol to prepare degradation-controlled HA-ADH(WATER/ETHANOL). Three kinds of HA hydrogels were prepared by the crosslinking of HA-ADH(WATER) or HA-ADH(WATER/ETHANOL) with bis(sulfosuccinimidyl) suberate, and by the crosslinking of HA-OH with divinyl sulfone (DVS). In vitro and in vivo degradation tests showed that HA-DVS hydrogels were degraded most rapidly, followed by HA-ADH(WATER) hydrogels and HA-ADH(WATER/ETHANOL) hydrogels. There was no adverse effect during and after in vivo degradation tests. All of the HA hydrogel samples appeared to be biocompatible, according to the histological analysis with hematoxylin-eosin and Alcian blue. PMID:18022803

  11. Spinal Cord Stimulation and Augmentative Control Strategies for Leg Movement after Spinal Paralysis in Humans.

    PubMed

    Minassian, Karen; Hofstoetter, Ursula S

    2016-04-01

    Severe spinal cord injury is a devastating condition, tearing apart long white matter tracts and causing paralysis and disability of body functions below the lesion. But caudal to most injuries, the majority of neurons forming the distributed propriospinal system, the localized gray matter spinal interneuronal circuitry, and spinal motoneuron populations are spared. Epidural spinal cord stimulation can gain access to this neural circuitry. This review focuses on the capability of the human lumbar spinal cord to generate stereotyped motor output underlying standing and stepping, as well as full weight-bearing standing and rhythmic muscle activation during assisted treadmill stepping in paralyzed individuals in response to spinal cord stimulation. By enhancing the excitability state of the spinal circuitry, the stimulation can have an enabling effect upon otherwise "silent" translesional volitional motor control. Strategies for achieving functional movement in patients with severe injuries based on minimal translesional intentional control, task-specific proprioceptive feedback, and next-generation spinal cord stimulation systems will be reviewed. The role of spinal cord stimulation can go well beyond the immediate generation of motor output. With recently developed training paradigms, it can become a major rehabilitation approach in spinal cord injury for augmenting and steering trans- and sublesional plasticity for lasting therapeutic benefits. PMID:26890324

  12. Serotonin in the solitary tract nucleus shortens the laryngeal chemoreflex in anaesthetized neonatal rats.

    PubMed

    Donnelly, William T; Bartlett, Donald; Leiter, J C

    2016-07-01

    What is the central question of this study? Failure to terminate apnoea and arouse is likely to contribute to sudden infant death syndrome (SIDS). Serotonin is deficient in the brainstems of babies who died of SIDS. Therefore, we tested the hypothesis that serotonin in the nucleus of the solitary tract (NTS) would shorten reflex apnoea. What is the main finding and its importance? Serotonin microinjected into the NTS shortened the apnoea and respiratory inhibition associated with the laryngeal chemoreflex. Moreover, this effect was achieved through a 5-HT3 receptor. This is a new insight that is likely to be relevant to the pathogenesis of SIDS. The laryngeal chemoreflex (LCR), an airway-protective reflex that causes apnoea and bradycardia, has long been suspected as an initiating event in the sudden infant death syndrome. Serotonin (5-HT) and 5-HT receptors may be deficient in the brainstems of babies who die of sudden infant death syndrome, and 5-HT seems to be important in terminating apnoeas directly or in causing arousals or as part of the process of autoresuscitation. We hypothesized that 5-HT in the brainstem would limit the duration of the LCR. We studied anaesthetized rat pups between 7 and 21 days of age and made microinjections into the cisterna magna or into the nucleus of the solitary tract (NTS). Focal, bilateral microinjections of 5-HT into the caudal NTS significantly shortened the LCR. The 5-HT1a receptor antagonist, WAY 100635, did not affect the LCR consistently, nor did a 5-HT2 receptor antagonist, ketanserin, alter the duration of the LCR. The 5-HT3 specific agonist, 1-(3-chlorophenyl)-biguanide, microinjected bilaterally into the caudal NTS significantly shortened the LCR. Thus, endogenous 5-HT released within the NTS may curtail the respiratory depression that is part of the LCR, and serotonergic shortening of the LCR may be attributed to activation of 5-HT3 receptors within the NTS. 5-HT3 receptors are expressed presynaptically on C

  13. PARTICULATE CONTROL AT HIGH TEMPERATURE AND PRESSURE USING AUGMENTED GRANULAR BED FILTERS

    EPA Science Inventory

    The report gives results of experimental measurements (in fixed- and moving-bed filters) of the effect of electrostatic augmentation on granular bed filter particle collection efficiencies. Experimental findings included: (1) either polarizing the bed or charging the particles si...

  14. Sensitivity of control-augmented structure obtained by a system decomposition method

    NASA Technical Reports Server (NTRS)

    Sobieszczanskisobieski, Jaroslaw; Bloebaum, Christina L.; Hajela, Prabhat

    1988-01-01

    The verification of a method for computing sensitivity derivatives of a coupled system is presented. The method deals with a system whose analysis can be partitioned into subsets that correspond to disciplines and/or physical subsystems that exchange input-output data with each other. The method uses the partial sensitivity derivatives of the output with respect to input obtained for each subset separately to assemble a set of linear, simultaneous, algebraic equations that are solved for the derivatives of the coupled system response. This sensitivity analysis is verified using an example of a cantilever beam augmented with an active control system to limit the beam's dynamic displacements under an excitation force. The verification shows good agreement of the method with reference data obtained by a finite difference technique involving entire system analysis. The usefulness of a system sensitivity method in optimization applications by employing a piecewise-linear approach to the same numerical example is demonstrated. The method's principal merits are its intrinsically superior accuracy in comparison with the finite difference technique, and its compatibility with the traditional division of work in complex engineering tasks among specialty groups.

  15. Sensitivity of control-augmented structure obtained by a system decomposition method

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, Jaroslaw; Bloebaum, Christina L.; Hajela, Prabhat

    1991-01-01

    The verification of a method for computing sensitivity derivatives of a coupled system is presented. The method deals with a system whose analysis can be partitioned into subsets that correspond to disciplines and/or physical subsystems that exchange input-output data with each other. The method uses the partial sensitivity derivatives of the output with respect to input obtained for each subset separately to assemble a set of linear, simultaneous, algebraic equations that are solved for the derivatives of the coupled system response. This sensitivity analysis is verified using an example of a cantilever beam augmented with an active control system to limit the beam's dynamic displacements under an excitation force. The verification shows good agreement of the method with reference data obtained by a finite difference technique involving entire system analysis. The usefulness of a system sensitivity method in optimization applications by employing a piecewise-linear approach to the same numerical example is demonstrated. The method's principal merits are its intrinsically superior accuracy in comparison with the finite difference technique, and its compatibility with the traditional division of work in complex engineering tasks among specialty groups.

  16. Using family members to augment genetic case-control studies of a life-threatening disease.

    PubMed

    Chen, Lu; Weinberg, Clarice R; Chen, Jinbo

    2016-07-20

    Survival bias is difficult to detect and adjust for in case-control genetic association studies but can invalidate findings when only surviving cases are studied and survival is associated with the genetic variants under study. Here, we propose a design where one genotypes genetically informative family members (such as offspring, parents, and spouses) of deceased cases and incorporates that surrogate genetic information into a retrospective maximum likelihood analysis. We show that inclusion of genotype data from first-degree relatives permits unbiased estimation of genotype association parameters. We derive closed-form maximum likelihood estimates for association parameters under the widely used log-additive and dominant association models. Our proposed design not only permits a valid analysis but also enhances statistical power by augmenting the sample with indirectly studied individuals. Gene variants associated with poor prognosis can also be identified under this design. We provide simulation results to assess performance of the methods. Copyright © 2016 John Wiley & Sons, Ltd. PMID:26866629

  17. Analysis of Aeroheating Augmentation and Control Interference Due to Reaction Control System Jets on Blunt Capsules

    NASA Astrophysics Data System (ADS)

    Dyakonov, Artem Alexander

    Atmospheric entry capsules are frequently fitted with rocket nozzles as part of a Reaction Control System (RCS), which is used for attitude control and guidance maneuvers during entry. These rocket nozzles are installed on the rear wall of the capsule and the interaction of their exhaust with capsule's wake causes changes in aeroheating and aerodynamics. Changes in aeroheating may influence design of Thermal Protection System (TPS) and material secection, while changes in the surface pressure can cause unbalanced moments on the capsule and interfere with the native RCS control authority. Aerodynamic initerference of RCS must be understood and bounded for a sound controller design. The method to analyze aerothermal and aerodynamic effects of RCS on blunt capsules, presented in this dissertation, has been used in analyses of Mars Phoenix, Mars Science Laboratory (MSL) and Crewed Exploration Vehicle (CEV) RCS. As a result a working RCS design paradigm has been developed. This paradigm has been successfully applied to the design of RCS of Mars Science Laboratory (MSL) entry capsule.

  18. A piloted simulator investigation of side-stick controller/stability and control augmentation system requirements for helicopter visual flight tasks

    NASA Technical Reports Server (NTRS)

    Landis, K. H.; Dunford, P. J.; Aiken, E. W.; Hilbert, K. B.

    1984-01-01

    A piloted simulator experiment was conducted to assess the effects of side-stick controller characteristics and level of stability and control augmentation on handling qualities for several low-altitude control tasks. Visual flight tasks were simulated using four-window computer-generated imagery depicting either a nap-of-the-earth course or a runway with obstacles positioned to provide a slalom course. Both low speed and forward flight control laws were implemented, and a method for automatically switching control modes was developed. Variations in force-deflection characteristics and the number of axes controlled through an integrated side-stick were investigated. With high levels of stability and control augmentation, a four-axis controller with small-deflection in all four axes achieved satisfactory handling qualities for low-speed tasks.

  19. Augmenting sensorimotor control using "goal-aware" vibrotactile stimulation during reaching and manipulation behaviors.

    PubMed

    Tzorakoleftherakis, Emmanouil; Murphey, Todd D; Scheidt, Robert A

    2016-08-01

    We describe two sets of experiments that examine the ability of vibrotactile encoding of simple position error and combined object states (calculated from an optimal controller) to enhance performance of reaching and manipulation tasks in healthy human adults. The goal of the first experiment (tracking) was to follow a moving target with a cursor on a computer screen. Visual and/or vibrotactile cues were provided in this experiment, and vibrotactile feedback was redundant with visual feedback in that it did not encode any information above and beyond what was already available via vision. After only 10 minutes of practice using vibrotactile feedback to guide performance, subjects tracked the moving target with response latency and movement accuracy values approaching those observed under visually guided reaching. Unlike previous reports on multisensory enhancement, combining vibrotactile and visual feedback of performance errors conferred neither positive nor negative effects on task performance. In the second experiment (balancing), vibrotactile feedback encoded a corrective motor command as a linear combination of object states (derived from a linear-quadratic regulator implementing a trade-off between kinematic and energetic performance) to teach subjects how to balance a simulated inverted pendulum. Here, the tactile feedback signal differed from visual feedback in that it provided information that was not readily available from visual feedback alone. Immediately after applying this novel "goal-aware" vibrotactile feedback, time to failure was improved by a factor of three. Additionally, the effect of vibrotactile training persisted after the feedback was removed. These results suggest that vibrotactile encoding of appropriate combinations of state information may be an effective form of augmented sensory feedback that can be applied, among other purposes, to compensate for lost or compromised proprioception as commonly observed, for example, in stroke

  20. Augmented RIGS

    NASA Technical Reports Server (NTRS)

    Kaminskas, R. A.; Mcguire, D.

    1974-01-01

    The results of the Phase 2 Resonant Infrasonic Gauging System (RIGS) development program are presented. The program consisted of design, fabrication, and testing of an "augmented" RIGS concept. The RIGS is a gauging system capable of measuring propellant quantities in zero-g as well as under accelerated conditions. Except for hydrogen, it can be used to gauge virtually any propellant in liquid form, including cryogenics. The gage consists of a sensor unit which is attached to the propellant tank and an electronic control unit which may be positioned separately from the sensor. The control unit receives signals from the sensor as well as the propellant temperature measurement and the ullage gas pressure, and computes the propellant quantity in the tank.

  1. Semiochemical lures reduce emigration and enhance pest control services in open-field predator augmentation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Augmentation biocontrol is a commercially viable pest management tactic in enclosed glasshouse environments, but is far less effective in open-field agriculture where newly released enemies rapidly disperse from release sites. We tested the potential for behavior-modifying semiochemicals to increase...

  2. Adaptive Augmenting Control Flight Characterization Experiment on an F/A-18

    NASA Technical Reports Server (NTRS)

    VanZwieten, Tannen S.; Orr, Jeb S.; Wall, John H.; Gilligan, Eric T.

    2014-01-01

    This paper summarizes the Adaptive Augmenting Control (AAC) flight characterization experiments performed using an F/A-18 (TN 853). AAC was designed and developed specifically for launch vehicles, and is currently part of the baseline autopilot design for NASA's Space Launch System (SLS). The scope covered here includes a brief overview of the algorithm (covered in more detail elsewhere), motivation and benefits of flight testing, top-level SLS flight test objectives, applicability of the F/A-18 as a platform for testing a launch vehicle control design, test cases designed to fully vet the AAC algorithm, flight test results, and conclusions regarding the functionality of AAC. The AAC algorithm developed at Marshall Space Flight Center is a forward loop gain multiplicative adaptive algorithm that modifies the total attitude control system gain in response to sensed model errors or undesirable parasitic mode resonances. The AAC algorithm provides the capability to improve or decrease performance by balancing attitude tracking with the mitigation of parasitic dynamics, such as control-structure interaction or servo-actuator limit cycles. In the case of the latter, if unmodeled or mismodeled parasitic dynamics are present that would otherwise result in a closed-loop instability or near instability, the adaptive controller decreases the total loop gain to reduce the interaction between these dynamics and the controller. This is in contrast to traditional adaptive control logic, which focuses on improving performance by increasing gain. The computationally simple AAC attitude control algorithm has stability properties that are reconcilable in the context of classical frequency-domain criteria (i.e., gain and phase margin). The algorithm assumes that the baseline attitude control design is well-tuned for a nominal trajectory and is designed to adapt only when necessary. Furthermore, the adaptation is attracted to the nominal design and adapts only on an as-needed basis

  3. A flight investigation of the stability, control, and handling qualities of an augmented jet flap STOL airplane

    NASA Technical Reports Server (NTRS)

    Vomaske, R. F.; Innis, R. C.; Swan, B. E.; Grossmith, S. W.

    1978-01-01

    The stability, control, and handling qualities of an augmented jet flap STOL airplane are presented. The airplane is an extensively modified de Havilland Buffalo military transport. The modified airplane has two fan-jet engines which provide vectorable thrust and compressed air for the augmentor jet flap and Boundary-Layer Control (BLC). The augmentor and BLC air is cross ducted to minimize asymmetric moments produced when one engine is inoperative. The modifications incorporated in the airplane include a Stability Augmentation System (SAS), a powered elevator, and a powered lateral control system. The test gross weight of the airplane was between 165,000 and 209,000 N (37,000 and 47,000 lb). Stability, control, and handling qualities are presented for the airspeed range of 40 to 180 knots. The lateral-directional handling qualities are considered satisfactory for the normal operating range of 65 to 160 knots airspeed when the SAS is functioning. With the SAS inoperative, poor turn coordination and spiral instability are primary deficiencies contributing to marginal handling qualities in the landing approach. The powered elevator control system enhanced the controllability in pitch, particularly in the landing flare and stall recovery.

  4. Launch Vehicle Manual Steering with Adaptive Augmenting Control In-flight Evaluations of Adverse Interactions Using a Piloted Aircraft

    NASA Technical Reports Server (NTRS)

    Hanson, Curt; Miller, Chris; Wall, John H.; Vanzwieten, Tannen S.; Gilligan, Eric; Orr, Jeb S.

    2015-01-01

    An adaptive augmenting control algorithm for the Space Launch System has been developed at the Marshall Space Flight Center as part of the launch vehicles baseline flight control system. A prototype version of the SLS flight control software was hosted on a piloted aircraft at the Armstrong Flight Research Center to demonstrate the adaptive controller on a full-scale realistic application in a relevant flight environment. Concerns regarding adverse interactions between the adaptive controller and a proposed manual steering mode were investigated by giving the pilot trajectory deviation cues and pitch rate command authority. Two NASA research pilots flew a total of twenty five constant pitch-rate trajectories using a prototype manual steering mode with and without adaptive control.

  5. A Randomized, Controlled Trial of Cognitive-Behavioral Therapy for Augmenting Pharmacotherapy in Obsessive-Compulsive Disorder

    PubMed Central

    Simpson, Helen Blair; Foa, Edna B.; Liebowitz, Michael R.; Ledley, Deborah Roth; Huppert, Jonathan D.; Cahill, Shawn; Vermes, Donna; Schmidt, Andrew B.; Hembree, Elizabeth; Franklin, Martin; Campeas, Raphael; Hahn, Chang-Gyu; Petkova, Eva

    2014-01-01

    Objective Although serotonin reuptake inhibitors (SRIs) are approved for the treatment of obsessive-compulsive disorder (OCD), most OCD patients who have received an adequate SRI trial continue to have clinically significant OCD symptoms. The purpose of this study was to examine the effects of augmenting SRIs with exposure and ritual prevention, an established cognitive-behavioral therapy (CBT) for OCD. Method A randomized, controlled trial was conducted at two academic outpatient clinics to compare the effects of augmenting SRIs with exposure and ritual prevention versus stress management training, another form of CBT. Participants were adult outpatients (N=108) with primary OCD and a Yale-Brown Obsessive Compulsive Scale total score ≥16 despite a therapeutic SRI dose for at least 12 weeks prior to entry. Participants received 17 sessions of CBT (either exposure and ritual prevention or stress management training) twice a week while continuing SRI pharmacotherapy. Results Exposure and ritual prevention was superior to stress management training in reducing OCD symptoms. At week 8, significantly more patients receiving exposure and ritual prevention than patients receiving stress management training had a decrease in symptom severity of at least 25% (based on Yale-Brown Obsessive Compulsive Scale scores) and achieved minimal symptoms (defined as a Yale-Brown Obsessive Compulsive Scale score ≤12). Conclusions Augmentation of SRI pharmacotherapy with exposure and ritual prevention is an effective strategy for reducing OCD symptoms. However, 17 sessions were not sufficient to help most of these patients achieve minimal symptoms. PMID:18316422

  6. Thrust Augmentation Through Active Flow Control: Lessons from a Bluegill Sunfish

    NASA Astrophysics Data System (ADS)

    Akhtar, Imran; Mittal, Rajat; Lauder, George

    2002-11-01

    Numerical simulations are being used to analyze the effect that vortices shed from the dorsal fin have on the thrust of the tail fin for a Bluegill Sunfish. The simulations are being carried out using a Cartesian grid method which allows us to simulate flows with complex moving boundararies on stationary Cartesian grids. The simulations attempt to model the kinematics of the fin motion and the flow conditions as measured by Drucker & Lauder (J. Exp. Bio. Vol. 202, pp 2393-2412, 1999) for a live specimen using PIV. Our simulations indicate that vortex shedding from the upstream dorsal fin is indeed capable of increasing the thrust of the tail fin significantly. However, this thrust augmentation is found to be quite sensitive to the phase relationship between the two flapping fins. Furthermore, the maximum thrust augmentation is found for phase angles that match those observed for the Bluegill Sunfish! The numerical simulation allow us to examine the underlying physical mechanism for this thrust augmentation and results pertaining to this will be presented.

  7. Development and human factors analysis of an augmented reality interface for multi-robot tele-operation and control

    NASA Astrophysics Data System (ADS)

    Lee, Sam; Lucas, Nathan P.; Ellis, R. Darin; Pandya, Abhilash

    2012-06-01

    This paper presents a seamlessly controlled human multi-robot system comprised of ground and aerial robots of semiautonomous nature for source localization tasks. The system combines augmented reality interfaces capabilities with human supervisor's ability to control multiple robots. The role of this human multi-robot interface is to allow an operator to control groups of heterogeneous robots in real time in a collaborative manner. It used advanced path planning algorithms to ensure obstacles are avoided and that the operators are free for higher-level tasks. Each robot knows the environment and obstacles and can automatically generate a collision-free path to any user-selected target. It displayed sensor information from each individual robot directly on the robot in the video view. In addition, a sensor data fused AR view is displayed which helped the users pin point source information or help the operator with the goals of the mission. The paper studies a preliminary Human Factors evaluation of this system in which several interface conditions are tested for source detection tasks. Results show that the novel Augmented Reality multi-robot control (Point-and-Go and Path Planning) reduced mission completion times compared to the traditional joystick control for target detection missions. Usability tests and operator workload analysis are also investigated.

  8. NK1 receptor activation in rat rostral ventrolateral medulla selectively attenuates somato-sympathetic reflex while antagonism attenuates sympathetic chemoreflex.

    PubMed

    Makeham, John M; Goodchild, Ann K; Pilowsky, Paul M

    2005-06-01

    The effects of activation and blockade of the neurokinin 1 (NK1) receptor in the rostral ventrolateral medulla (RVLM) on arterial blood pressure (ABP), splanchnic sympathetic nerve activity (sSNA), phrenic nerve activity, the somato-sympathetic reflex, baroreflex, and chemoreflex were studied in urethane-anesthetized and artificially ventilated Sprague-Dawley rats. Bilateral microinjection of either the stable substance P analog (pGlu5, MePhe8, Sar9)SP(5-11) (DiMe-SP) or the highly selective NK1 agonist [Sar9, Met (O(2))11]SP into the RVLM resulted in an increase in ABP, sSNA, and heart rate and an abolition of phrenic nerve activity. The effects of [Sar9, Met (O(2))11]SP were blocked by the selective nonpeptide NK1 receptor antagonist WIN 51708. NK1 receptor activation also dramatically attenuated the somato-sympathetic reflex elicited by tibial nerve stimulation, while leaving the baroreflex and chemoreflex unaffected. This effect was again blocked by WIN 51708. NK1 receptor antagonism in the RVLM, with WIN 51708 significantly attenuated the sympathoexcitatory response to hypoxia but had no effect on baseline respiratory function. Our findings suggest that substance P and the NK1 receptor play a significant role in the cardiorespiratory reflexes integrated within the RVLM. PMID:15731401

  9. RMS active damping augmentation

    NASA Technical Reports Server (NTRS)

    Gilbert, Michael G.; Scott, Michael A.; Demeo, Martha E.

    1992-01-01

    The topics are presented in viewgraph form and include: RMS active damping augmentation; potential space station assembly benefits to CSI; LaRC/JSC bridge program; control law design process; draper RMS simulator; MIMO acceleration control laws improve damping; potential load reduction benefit; DRS modified to model distributed accelerations; accelerometer location; Space Shuttle aft cockpit simulator; simulated shuttle video displays; SES test goals and objectives; and SES modifications to support RMS active damping augmentation.

  10. Issues of Mitigation Strategies in Augmented System for Next Generation Control Room

    SciTech Connect

    Tuan Q. Tran

    2007-08-01

    Past research on augmented systems has been predominately concerned with measuring and classifying an operator’s functional states. Only recently has the field begun researching mitigation strategies. The purpose of this paper is to add further conceptual understanding to mitigation strategies. Based upon the decision making literature, we pose three issues that mitigation strategies need to resolve: the types of decision strategies an operator uses, the structure of the information that an operator processes, and finally, the cue or pattern of cues that the operator relies on in making decisions. These issues are important to ensure that mitigation strategies are congruent to operator’s decision-making behaviors.

  11. Flight Testing of the Space Launch System (SLS) Adaptive Augmenting Control (AAC) Algorithm on an F/A-18

    NASA Technical Reports Server (NTRS)

    Dennehy, Cornelius J.; VanZwieten, Tannen S.; Hanson, Curtis E.; Wall, John H.; Miller, Chris J.; Gilligan, Eric T.; Orr, Jeb S.

    2014-01-01

    The Marshall Space Flight Center (MSFC) Flight Mechanics and Analysis Division developed an adaptive augmenting control (AAC) algorithm for launch vehicles that improves robustness and performance on an as-needed basis by adapting a classical control algorithm to unexpected environments or variations in vehicle dynamics. This was baselined as part of the Space Launch System (SLS) flight control system. The NASA Engineering and Safety Center (NESC) was asked to partner with the SLS Program and the Space Technology Mission Directorate (STMD) Game Changing Development Program (GCDP) to flight test the AAC algorithm on a manned aircraft that can achieve a high level of dynamic similarity to a launch vehicle and raise the technology readiness of the algorithm early in the program. This document reports the outcome of the NESC assessment.

  12. Ribavirin in Cancer Immunotherapies: Controlling Nitric Oxide Augments Cytotoxic Lymphocyte Function

    PubMed Central

    Kast, Richard E

    2003-01-01

    Abstract Either ribavirin (RBV) or cyclophosphamide (CY) can shift an immune response from Th2 toward a Th1 cytokine profile. CY is used in this role in various current cancer immunotherapy attempts but with mixed success. More potent and reliable immunoadjuvants and Th1 response biasing methods are needed. RBV is used today mainly to augment interferon-alpha treatment of hepatitis C. RBV shifts an immune response from Th2 toward Th1 more effectively than CY and may be a safe and useful adjuvant for current cancer immunotherapeutic efforts. RBV is thought to act by inhibition of tetrahydrobiopterin synthesis. Tetrahydrobiopterin is an essential cofactor for all known isoforms of nitric oxide synthase. Lowered nitric oxide favors Th1 development as high levels favor Th2 weighting. PMID:12659664

  13. Preliminary control law and hardware designs for a ride quality augmentation system for commuter aircraft. Phase 2

    NASA Technical Reports Server (NTRS)

    Davis, D. J.; Linse, D. J.; Suikat, R.; Entz, D. P.

    1986-01-01

    The continued investigation of the design of Ride Quality Augmentation Systems (RQAS) for commuter aircraft is described. The purpose of these RQAS is the reduction of the vertical and lateral acceleration response of the aircraft due to atmospheric turbulence by the application of active control. The current investigations include the refinement of the sample data feedback control laws based on the control-rate-weighting and output-weighting optimal control design techniqes. These control designs were evaluated using aircraft time simulations driven by Dryden spectra turbulence. Fixed gain controllers were tested throughout the aircrft operating envelope. The preliminary design of the hardware modifications necessary to implement and test the RQAS on a commuter aircraft is included. These include a separate surface elevator and the flap modifications to provide both direct lift and roll control. A preliminary failure mode investigation was made for the proposed configuration. The results indicate that vertical acceleration reductions of 45% and lateral reductions of more than 50% are possible. A fixed gain controller appears to be feasible with only minor response degradation.

  14. Augmented Thermal Bus

    NASA Technical Reports Server (NTRS)

    Schrage, Dean S. (Inventor)

    1996-01-01

    The present invention is directed to an augmented thermal bus. In the present design a plurality of thermo-electric heat pumps are used to couple a source plate to a sink plate. Each heat pump is individually controlled by a model based controller. The controller coordinates the heat pumps to maintain isothermality in the source.

  15. Augmented thermal bus

    NASA Technical Reports Server (NTRS)

    Schrage, Dean S. (Inventor)

    1993-01-01

    The present invention is directed to an augmented thermal bus. In the present design a plurity of thermo-electric heat pumps are used to couple a source plate to a sink plate. Each heat pump is individually controlled by a model based controller. The controller coordinates the heat pump to maintain isothermality in the source.

  16. Reconfigurable Control Design with Neural Network Augmentation for a Modified F-15 Aircraft

    NASA Technical Reports Server (NTRS)

    Burken, John J.

    2007-01-01

    The viewgraphs present background information about reconfiguration control design, design methods used for paper, control failure survivability results, and results and time histories of tests. Topics examined include control reconfiguration, general information about adaptive controllers, model reference adaptive control (MRAC), the utility of neural networks, radial basis functions (RBF) neural network outputs, neurons, and results of investigations of failures.

  17. Launch Vehicle Manual Steering with Adaptive Augmenting Control:In-Flight Evaluations of Adverse Interactions Using a Piloted Aircraft

    NASA Technical Reports Server (NTRS)

    Hanson, Curt; Miller, Chris; Wall, John H.; VanZwieten, Tannen S.; Gilligan, Eric T.; Orr, Jeb S.

    2015-01-01

    An Adaptive Augmenting Control (AAC) algorithm for the Space Launch System (SLS) has been developed at the Marshall Space Flight Center (MSFC) as part of the launch vehicle's baseline flight control system. A prototype version of the SLS flight control software was hosted on a piloted aircraft at the Armstrong Flight Research Center to demonstrate the adaptive controller on a full-scale realistic application in a relevant flight environment. Concerns regarding adverse interactions between the adaptive controller and a potential manual steering mode were also investigated by giving the pilot trajectory deviation cues and pitch rate command authority, which is the subject of this paper. Two NASA research pilots flew a total of 25 constant pitch rate trajectories using a prototype manual steering mode with and without adaptive control, evaluating six different nominal and off-nominal test case scenarios. Pilot comments and PIO ratings were given following each trajectory and correlated with aircraft state data and internal controller signals post-flight.

  18. Cardiovascular responses to peripheral chemoreflex activation and comparison of different methods to evaluate baroreflex gain in conscious mice using telemetry.

    PubMed

    Braga, Valdir A; Burmeister, Melissa A; Sharma, Ram V; Davisson, Robin L

    2008-10-01

    Peripheral chemoreceptors located in the carotid bodies are the primary sensors of systemic hypoxia. Although the pattern of responses elicited by peripheral chemoreceptor activation is well established in rats, lambs, and rabbits, the cardiovascular responses to peripheral chemoreflex activation in conscious mice have not been delineated. Here we report that stimulation of peripheral chemoreceptors by potassium cyanide (KCN) in conscious mice elicits a unique biphasic response in blood pressure that is characterized by an initial and robust rise followed by a decrease in blood pressure, which is accompanied by a marked reduction in heart rate. The depressor and bradycardic responses to KCN were abolished by muscarinic receptor blockade with atropine, and the pressor response was abolished by alpha-adrenergic receptor blockade with prazosin, suggesting that vagal and sympathetic drive to the heart and sympathetic drive to the vasculature mediate these cardiovascular responses. These studies characterized the chemoreflex in conscious mice and established the reliability of using them for studying hypoxia-related diseases such as obstructive sleep apnea. In another series of experiments, two methods for analyzing baroreflex sensitivity were compared: the classical pharmacological approach using phenylephrine and sodium nitroprusside (i.e., the Oxford technique) or the sequence method for analyzing spontaneous baroreflex activity. Our findings indicate that both methods are reliable, and the sequence method certainly has its benefits as a predictive tool in the context of long-term noninvasive studies using telemetry. However, for absolute determination of baroreflex function, analysis of spontaneous baroreflex activity should be complemented by the classical pharmacological method. PMID:18667715

  19. Active structural control for damping augmentation and compensation of thermal distortion

    NASA Technical Reports Server (NTRS)

    Sirlin, S. W.

    1992-01-01

    A large space-based Focus Mission Interferometer is used as a testbed for the NASA Controls and Structures Interaction Program. Impedance-based adaptive structural control and control of thermal disturbances are demonstrated using an end-to-end simulation of the system's optical performance. Attention is also given to integrated optical/structural modeling and a hierarchical, layered control strategy.

  20. Can Atypical Antipsychotic Augmentation Reduce Subsequent Treatment Failure More Effectively Among Depressed Patients with a Higher Degree of Treatment Resistance? A Meta-Analysis of Randomized Controlled Trials

    PubMed Central

    Wang, Hee Ryung; Woo, Young Sup; Ahn, Hyeong Sik; Ahn, Il Min; Kim, Hyun Jung; Bahk, Won-Myong

    2015-01-01

    Background: Atypical antipsychotic augmentation was demonstrated to be efficacious in treatment-resistant depression (TRD) in previous meta-analyses. We investigate whether there are differences in the effect size of atypical antipsychotic augmentation in major depressive disorder according to the degree of treatment resistance. Methods: A comprehensive search of four databases identified 11 randomized controlled trials. The 11 trials, which included 3 341 participants, were pooled using a random-effects meta-analysis. Results: Atypical antipsychotic augmentation of antidepressant therapy showed superior efficacy compared to antidepressant monotherapy in TRD in terms of both response and remission rates (response, risk ratio [RR] = 1.38, 95% confidence interval [CI] = 1.25 to 1.53; remission, RR = 1.62, 95% CI = 1.42 to 1.85). In addition, regarding response rates in the TRD trials, atypical antipsychotic augmentation exhibited significantly different effect sizes according to the degree of treatment resistance (TRD 1: RR = 1.24; TRD 2: RR = 1.37; TRD 2–4: RR = 1.58). In non-TRD trials, atypical antipsychotic augmentation failed to show superior efficacy over antidepressant monotherapy in terms of remission rates (RR = 0.89; 95% CI = 0.69 to 1.14). Atypical antipsychotic augmentation of antidepressant therapy exhibits greater effect size in patients with a higher degree of treatment resistance. Conclusions: This finding strengthens the rationale for considering atypical antipsychotic augmentation among depressed patients with multiple previous treatment failures in clinical practice. The efficacy of atypical antipsychotic augmentation for non-TRD seems to be different from that for TRD and, thus, further studies of non-TRD populations are needed. PMID:25770098

  1. Study protocol for the randomised controlled trial: Antiglucocorticoid augmentation of anti-Depressants in Depression (The ADD Study)

    PubMed Central

    2013-01-01

    Background Some patients with depression do not respond to first and second line conventional antidepressants and are therefore characterised as suffering from treatment refractory depression (TRD). On-going psychosocial stress and dysfunction of the hypothalamic-pituitary-adrenal axis are both associated with an attenuated clinical response to antidepressants. Preclinical data shows that co-administration of corticosteroids leads to a reduction in the ability of selective serotonin reuptake inhibitors to increase forebrain 5-hydroxytryptamine, while co-administration of antiglucocorticoids has the opposite effect. A Cochrane review suggests that antiglucocorticoid augmentation of antidepressants may be effective in treating TRD and includes a pilot study of the cortisol synthesis inhibitor, metyrapone. The Antiglucocorticoid augmentation of anti-Depressants in Depression (The ADD Study) is a multicentre randomised placebo controlled trial of metyrapone augmentation of serotonergic antidepressants in a large population of patients with TRD in the UK National Health Service. Methods/design Patients with moderate to severe treatment refractory Major Depression aged 18 to 65 will be randomised to metyrapone 500 mg twice daily or placebo for three weeks, in addition to on-going conventional serotonergic antidepressants. The primary outcome will be improvement in Montgomery-Åsberg Depression Rating Scale score five weeks after randomisation (i.e. two weeks after trial medication discontinuation). Secondary outcomes will include the degree of persistence of treatment effect for up to 6 months, improvements in quality of life and also safety and tolerability of metyrapone. The ADD Study will also include a range of sub-studies investigating the potential mechanism of action of metyrapone. Discussion Strengths of the ADD study include broad inclusion criteria meaning that the sample will be representative of patients with TRD treated within the UK National Health

  2. Lip augmentation.

    PubMed

    Byrne, Patrick J; Hilger, Peter A

    2004-02-01

    Lip augmentation has become increasingly popular in recent years as a reflection of cultural trends emphasizing youth and beauty. Techniques to enhance the appearance of the lips have evolved with advances in biotechnology. An understanding of lip anatomy and aesthetics forms the basis for successful results. We outline the pertinent anatomy and aesthetics of the preoperative evaluation. A summary of various filler materials available is provided. Augmentation options include both injectable and open surgical techniques. The procedures and materials currently favored by the authors are described in greater detail. PMID:15034811

  3. Flow Control Research at NASA Langley in Support of High-Lift Augmentation

    NASA Technical Reports Server (NTRS)

    Sellers, William L., III; Jones, Gregory S.; Moore, Mark D.

    2002-01-01

    The paper describes the efforts at NASA Langley to apply active and passive flow control techniques for improved high-lift systems, and advanced vehicle concepts utilizing powered high-lift techniques. The development of simplified high-lift systems utilizing active flow control is shown to provide significant weight and drag reduction benefits based on system studies. Active flow control that focuses on separation, and the development of advanced circulation control wings (CCW) utilizing unsteady excitation techniques will be discussed. The advanced CCW airfoils can provide multifunctional controls throughout the flight envelope. Computational and experimental data are shown to illustrate the benefits and issues with implementation of the technology.

  4. An Action Dependent Heuristic Dynamic Programming-controlled Superconducting Magnetic Energy Storage for Transient Stability Augmentation

    NASA Astrophysics Data System (ADS)

    Wang, Xinpu; Yang, Jun; Zhang, Xiaodong; Yu, Xiaopeng

    To enhance the stability of power system, the active power and reactive power can be absorbed from or released to Superconducting magnetic energy storage (SMES) unit according to system power requirements. This paper proposes a control strategy based on action dependent heuristic dynamic programing (ADHDP) which can control SMES to improve the stability of electric power system with on-line learning ability. Based on back propagation (BP) neural network, ADHDP approximates the optimal control solution of nonlinear system through iteration step by step. This on-line learning ability improves its performance by learning from its own mistakes through reinforcement signal from external environment, so that it can adjust the neural network weights according to the back propagation error to achieve optimal control performance. To investigate the effectiveness of the proposed control strategy, simulation tests are carried out in Matlab/Simulink. And a conventional Proportional-Integral (PI) controlled method is used to compare the performance of ADHDP. Simulation results show that the proposed controller demonstrates superior damping performance on power system oscillation caused by three-phase fault and wind power fluctuation over the PI controller.

  5. Augmented Adaptive Control of a Wind Turbine in the Presence of Structural Modes

    NASA Technical Reports Server (NTRS)

    Frost, Susan A.; Balas, Mark J.; Wright, Alan D.

    2010-01-01

    Wind turbines operate in highly turbulent environments resulting in aerodynamic loads that can easily excite turbine structural modes, potentially causing component fatigue and failure. Two key technology drivers for turbine manufacturers are increasing turbine up time and reducing maintenance costs. Since the trend in wind turbine design is towards larger, more flexible turbines with lower frequency structural modes, manufacturers will want to develop methods to operate in the presence of these modes. Accurate models of the dynamic characteristics of new wind turbines are often not available due to the complexity and expense of the modeling task, making wind turbines ideally suited to adaptive control. In this paper, we develop theory for adaptive control with rejection of disturbances in the presence of modes that inhibit the controller. We use this method to design an adaptive collective pitch controller for a high-fidelity simulation of a utility-scale, variable-speed wind turbine operating in Region 3. The objective of the adaptive pitch controller is to regulate generator speed, accommodate wind gusts, and reduce the interference of certain structural modes in feedback. The control objective is accomplished by collectively pitching the turbine blades. The adaptive pitch controller for Region 3 is compared in simulations with a baseline classical Proportional Integrator (PI) collective pitch controller.

  6. Virtual Planning, Control, and Machining for a Modular-Based Automated Factory Operation in an Augmented Reality Environment

    NASA Astrophysics Data System (ADS)

    Pai, Yun Suen; Yap, Hwa Jen; Md Dawal, Siti Zawiah; Ramesh, S.; Phoon, Sin Ye

    2016-06-01

    This study presents a modular-based implementation of augmented reality to provide an immersive experience in learning or teaching the planning phase, control system, and machining parameters of a fully automated work cell. The architecture of the system consists of three code modules that can operate independently or combined to create a complete system that is able to guide engineers from the layout planning phase to the prototyping of the final product. The layout planning module determines the best possible arrangement in a layout for the placement of various machines, in this case a conveyor belt for transportation, a robot arm for pick-and-place operations, and a computer numerical control milling machine to generate the final prototype. The robotic arm module simulates the pick-and-place operation offline from the conveyor belt to a computer numerical control (CNC) machine utilising collision detection and inverse kinematics. Finally, the CNC module performs virtual machining based on the Uniform Space Decomposition method and axis aligned bounding box collision detection. The conducted case study revealed that given the situation, a semi-circle shaped arrangement is desirable, whereas the pick-and-place system and the final generated G-code produced the highest deviation of 3.83 mm and 5.8 mm respectively.

  7. Virtual Planning, Control, and Machining for a Modular-Based Automated Factory Operation in an Augmented Reality Environment.

    PubMed

    Pai, Yun Suen; Yap, Hwa Jen; Md Dawal, Siti Zawiah; Ramesh, S; Phoon, Sin Ye

    2016-01-01

    This study presents a modular-based implementation of augmented reality to provide an immersive experience in learning or teaching the planning phase, control system, and machining parameters of a fully automated work cell. The architecture of the system consists of three code modules that can operate independently or combined to create a complete system that is able to guide engineers from the layout planning phase to the prototyping of the final product. The layout planning module determines the best possible arrangement in a layout for the placement of various machines, in this case a conveyor belt for transportation, a robot arm for pick-and-place operations, and a computer numerical control milling machine to generate the final prototype. The robotic arm module simulates the pick-and-place operation offline from the conveyor belt to a computer numerical control (CNC) machine utilising collision detection and inverse kinematics. Finally, the CNC module performs virtual machining based on the Uniform Space Decomposition method and axis aligned bounding box collision detection. The conducted case study revealed that given the situation, a semi-circle shaped arrangement is desirable, whereas the pick-and-place system and the final generated G-code produced the highest deviation of 3.83 mm and 5.8 mm respectively. PMID:27271840

  8. Virtual Planning, Control, and Machining for a Modular-Based Automated Factory Operation in an Augmented Reality Environment

    PubMed Central

    Pai, Yun Suen; Yap, Hwa Jen; Md Dawal, Siti Zawiah; Ramesh, S.; Phoon, Sin Ye

    2016-01-01

    This study presents a modular-based implementation of augmented reality to provide an immersive experience in learning or teaching the planning phase, control system, and machining parameters of a fully automated work cell. The architecture of the system consists of three code modules that can operate independently or combined to create a complete system that is able to guide engineers from the layout planning phase to the prototyping of the final product. The layout planning module determines the best possible arrangement in a layout for the placement of various machines, in this case a conveyor belt for transportation, a robot arm for pick-and-place operations, and a computer numerical control milling machine to generate the final prototype. The robotic arm module simulates the pick-and-place operation offline from the conveyor belt to a computer numerical control (CNC) machine utilising collision detection and inverse kinematics. Finally, the CNC module performs virtual machining based on the Uniform Space Decomposition method and axis aligned bounding box collision detection. The conducted case study revealed that given the situation, a semi-circle shaped arrangement is desirable, whereas the pick-and-place system and the final generated G-code produced the highest deviation of 3.83 mm and 5.8 mm respectively. PMID:27271840

  9. Pilot-optimal augmentation synthesis

    NASA Technical Reports Server (NTRS)

    Schmidt, D. K.

    1978-01-01

    An augmentation synthesis method usable in the absence of quantitative handling qualities specifications, and yet explicitly including design objectives based on pilot-rating concepts, is presented. The algorithm involves the unique approach of simultaneously solving for the stability augmentation system (SAS) gains, pilot equalization and pilot rating prediction via optimal control techniques. Simultaneous solution is required in this case since the pilot model (gains, etc.) depends upon the augmented plant dynamics, and the augmentation is obviously not a priori known. Another special feature is the use of the pilot's objective function (from which the pilot model evolves) to design the SAS.

  10. Development and flight evaluation of an augmented stability active controls concept with a small horizontal tail

    NASA Technical Reports Server (NTRS)

    Rising, J. J.; Kairys, A. A.; Maass, C. A.; Siegart, C. D.; Rakness, W. L.; Mijares, R. D.; King, R. W.; Peterson, R. S.; Hurley, S. R.; Wickson, D.

    1982-01-01

    A limited authority pitch active control system (PACS) was developed for a wide body jet transport (L-1011) with a flying horizontal stabilizer. Two dual channel digital computers and the associated software provide command signals to a dual channel series servo which controls the stabilizer power actuators. Input sensor signals to the computer are pitch rate, column-trim position, and dynamic pressure. Control laws are given for the PACS and the system architecture is defined. The piloted flight simulation and vehicle system simulation tests performed to verify control laws and system operation prior to installation on the aircraft are discussed. Modifications to the basic aircraft are described. Flying qualities of the aircraft with the PACS on and off were evaluated. Handling qualities for cruise and high speed flight conditions with the c.g. at 39% mac ( + 1% stability margin) and PACS operating were judged to be as good as the handling qualities with the c.g. at 25% (+15% stability margin) and PACS off.

  11. Augmentative Biological Control Using Parasitoids for Fruit Fly Management in Brazil.

    PubMed

    Garcia, Flávio R M; Ricalde, Marcelo P

    2012-01-01

    The history of classical biological control of fruit flies in Brazil includes two reported attempts in the past 70 years. The first occurred in 1937 when an African species of parasitoid larvae (Tetrastichus giffardianus) was introduced to control the Mediterranean fruit fly, Ceratitis capitata and other tephritids. The second occurred in September 1994 when the exotic parasitoid Diachasmimorpha longicaudata, originally from Gainesville, Florida, was introduced by a Brazilian agricultural corporation (EMBRAPA) to evaluate the parasitoid's potential for the biological control of Anastrepha spp. and Ceratitis capitata. Although there are numerous native Brazilian fruit fly parasitoids, mass rearing of these native species is difficult. Thus, D. longicaudata was chosen due to its specificity for the family Tephritidae and its ease of laboratory rearing. In this paper we review the literature on Brazilian fruit fly biological control and suggest that those tactics can be used on a large scale, together creating a biological barrier to the introduction of new fruit fly populations, reducing the source of outbreaks and the risk of species spread, while decreasing the use of insecticides on fruit destined for domestic and foreign markets. PMID:26466795

  12. Augmentative Biological Control Using Parasitoids for Fruit Fly Management in Brazil

    PubMed Central

    Garcia, Flávio R. M.; Ricalde, Marcelo P.

    2012-01-01

    The history of classical biological control of fruit flies in Brazil includes two reported attempts in the past 70 years. The first occurred in 1937 when an African species of parasitoid larvae (Tetrastichus giffardianus) was introduced to control the Mediterranean fruit fly, Ceratitis capitata and other tephritids. The second occurred in September 1994 when the exotic parasitoid Diachasmimorpha longicaudata, originally from Gainesville, Florida, was introduced by a Brazilian agricultural corporation (EMBRAPA) to evaluate the parasitoid’s potential for the biological control of Anastrepha spp. and Ceratitis capitata. Although there are numerous native Brazilian fruit fly parasitoids, mass rearing of these native species is difficult. Thus, D. longicaudata was chosen due to its specificity for the family Tephritidae and its ease of laboratory rearing. In this paper we review the literature on Brazilian fruit fly biological control and suggest that those tactics can be used on a large scale, together creating a biological barrier to the introduction of new fruit fly populations, reducing the source of outbreaks and the risk of species spread, while decreasing the use of insecticides on fruit destined for domestic and foreign markets. PMID:26466795

  13. Chin augmentation.

    PubMed

    Choe, K S; Stucki-McCormick, S U

    2000-01-01

    The primary goal of facial aesthetic surgery is to restore, enhance, and rejuvenate the aging face to a more youthful appearance, achieving balance and harmony. The mental area must be addressed in order to have a complete synthesis of the face. The concept of augmenting the mental area with implants has evolved so significantly that it now stands by itself as an important procedure. Various autogenous implants for chin augmentation have been in use for over 100 years but have complications. The advent of synthetic materials has given rise to various types of alloplastic implants: Gore-Tex, Medpor, Supramid, Silastic, and Mersilene. No one implant is perfect for every face. This article overviews several alloplastic implants--their advantages, disadvantages, and complications, in addition to the different techniques of preparing and delivering the implants. PMID:11802346

  14. Time of day affects chemoreflex sensitivity and the carbon dioxide reserve during NREM sleep in participants with sleep apnea.

    PubMed

    El-Chami, Mohamad; Shaheen, David; Ivers, Blake; Syed, Ziauddin; Badr, M Safwan; Lin, Ho-Sheng; Mateika, Jason H

    2014-11-15

    Our investigation was designed to determine whether the time of day affects the carbon dioxide reserve and chemoreflex sensitivity during non-rapid eye movement (NREM) sleep. Ten healthy men with obstructive sleep apnea completed a constant routine protocol that consisted of sleep sessions in the evening (10 PM to 1 AM), morning (6 AM to 9 AM), and afternoon (2 PM to 5 PM). Between sleep sessions, the participants were awake. During each sleep session, core body temperature, baseline levels of carbon dioxide (PET(CO2)) and minute ventilation, as well as the PET(CO2) that demarcated the apneic threshold and hypocapnic ventilatory response, were measured. The nadir of core body temperature during sleep occurred in the morning and was accompanied by reductions in minute ventilation and PetCO2 compared with the evening and afternoon (minute ventilation: 5.3 ± 0.3 vs. 6.2 ± 0.2 vs. 6.1 ± 0.2 l/min, P < 0.02; PET(CO2): 39.7 ± 0.4 vs. 41.4 ± 0.6 vs. 40.4 ± 0.6 Torr, P < 0.02). The carbon dioxide reserve was reduced, and the hypocapnic ventilatory response increased in the morning compared with the evening and afternoon (carbon dioxide reserve: 2.1 ± 0.3 vs. 3.6 ± 0.5 vs. 3.5 ± 0.3 Torr, P < 0.002; hypocapnic ventilatory response: 2.3 ± 0.3 vs. 1.6 ± 0.2 vs. 1.8 ± 0.2 l·min(-1)·mmHg(-1), P < 0.001). We conclude that time of day affects chemoreflex properties during sleep, which may contribute to increases in breathing instability in the morning compared with other periods throughout the day/night cycle in individuals with sleep apnea. PMID:25213638

  15. Organelle size control - increasing vacuole content activates SNAREs to augment organelle volume through homotypic fusion.

    PubMed

    Desfougères, Yann; Neumann, Heinz; Mayer, Andreas

    2016-07-15

    Cells control the size of their compartments relative to cell volume, but there is also size control within each organelle. Yeast vacuoles neither burst nor do they collapse into a ruffled morphology, indicating that the volume of the organellar envelope is adjusted to the amount of content. It is poorly understood how this adjustment is achieved. We show that the accumulating content of yeast vacuoles activates fusion of other vacuoles, thus increasing the volume-to-surface ratio. Synthesis of the dominant compound stored inside vacuoles, polyphosphate, stimulates binding of the chaperone Sec18/NSF to vacuolar SNAREs, which activates them and triggers fusion. SNAREs can only be activated by lumenal, not cytosolic, polyphosphate (polyP). Control of lumenal polyP over SNARE activation in the cytosol requires the cytosolic cyclin-dependent kinase Pho80-Pho85 and the R-SNARE Nyv1. These results suggest that cells can adapt the volume of vacuoles to their content through feedback from the vacuole lumen to the SNAREs on the cytosolic surface of the organelle. PMID:27252384

  16. Controlled Cavitation to Augment SWL Stone Comminution: Mechanistic Insights In-Vitro

    PubMed Central

    Duryea, Alexander P.; Roberts, William W.; Cain, Charles A.; Hall, Timothy L.

    2013-01-01

    Stone comminution in shock wave lithotripsy (SWL) has been documented to result from mechanical stresses conferred directly to the stone, as well as the activity of cavitational microbubbles. Studies have demonstrated that the presence of this cavitation activity is crucial for stone subdivision; however, its exact role in the comminution process remains somewhat weakly defined, in part due to the fact that it is difficult to isolate the cavitational component from the shock waves themselves. In this study, we further explored the importance of cavitation in SWL stone comminution through the use of histotripsy ultrasound therapy. Histotripsy was utilized to target model stones designed to mimic the mid-range tensile fracture strength of naturally occurring cystine calculi with controlled cavitation at strategic time points in the SWL comminution process. All SWL was applied at a peak-positive pressure (p+) of 34 MPa and a peak-negative pressure (p−) of 8 MPa; a shock rate of 1 Hz was used. Histotripsy pulses had a p− of 33 MPa and were applied at a pulse repetition frequency (PRF) of 100 Hz. Ten model stones were sonicated in-vitro with each of five different treatment schemes: A. 10 minutes SWL (600 shocks) with 0.7 seconds of histotripsy interleaved between successive shocks (totaling to 42,000 pulses); B. 10 minutes SWL (600 shocks) followed by 10 minutes histotripsy applied in 0.7 second bursts (1 burst per second, totaling to 42,000 pulses); C. 10 minutes histotripsy applied in 0.7 second bursts (42,000 pulses) followed by 10 minutes SWL (600 shocks); D. 10 minutes SWL-only (600 shocks); E. 10 minutes histotripsy-only applied in 0.7 second bursts (42,000 pulses). Following sonication, debris was collected and sieved through 8, 6, 4, and 2 mm filters. It was found that SWL-only generated a broad range of fragment sizes, with an average of 14.9 ± 24.1% of the original stone mass remaining >8 mm. Histotripsy-only eroded the surface of stones to tiny

  17. An electrooculogram-based binary saccade sequence classification (BSSC) technique for augmentative communication and control.

    PubMed

    Keegan, Johnalan; Burke, Edward; Condron, James

    2009-01-01

    In the field of assistive technology, the electrooculogram (EOG) can be used as a channel of communication and the basis of a man-machine interface. For many people with severe motor disabilities, simple actions such as changing the TV channel require assistance. This paper describes a method of detecting saccadic eye movements and the use of a saccade sequence classification algorithm to facilitate communication and control. Saccades are fast eye movements that occurs when a person's gaze jumps from one fixation point to another. The classification is based on pre-defined sequences of saccades, guided by a static visual template (e.g. a page or poster). The template, consisting of a table of symbols each having a clearly identifiable fixation point, is situated within view of the user. To execute a particular command, the user moves his or her gaze through a pre-defined path of eye movements. This results in a well-formed sequence of saccades which are translated into a command if a match is found in a library of predefined sequences. A coordinate transformation algorithm is applied to each candidate sequence of recorded saccades to mitigate the effect of changes in the user's position and orientation relative to the visual template. Upon recognition of a saccade sequence from the library, its associated command is executed. A preliminary experiment in which two subjects were instructed to perform a series of command sequences consisting of 8 different commands are presented in the final sections. The system is also shown to be extensible to facilitate convenient text entry via an alphabetic visual template. PMID:19965222

  18. In-Flight Suppression of a De-Stabilized F/A-18 Structural Mode Using the Space Launch System Adaptive Augmenting Control System

    NASA Technical Reports Server (NTRS)

    Wall, John; VanZwieten, Tannen; Giiligan Eric; Miller, Chris; Hanson, Curtis; Orr, Jeb

    2015-01-01

    Adaptive Augmenting Control (AAC) has been developed for NASA's Space Launch System (SLS) family of launch vehicles and implemented as a baseline part of its flight control system (FCS). To raise the technical readiness level of the SLS AAC algorithm, the Launch Vehicle Adaptive Control (LVAC) flight test program was conducted in which the SLS FCS prototype software was employed to control the pitch axis of Dryden's specially outfitted F/A-18, the Full Scale Advanced Systems Test Bed (FAST). This presentation focuses on a set of special test cases which demonstrate the successful mitigation of the unstable coupling of an F/A-18 airframe structural mode with the SLS FCS.

  19. Prolonged leucine supplementation does not augment muscle mass or affect glycemic control in elderly type 2 diabetic men.

    PubMed

    Leenders, Marika; Verdijk, Lex B; van der Hoeven, Letty; van Kranenburg, Janneau; Hartgens, Fred; Wodzig, Will K W H; Saris, Wim H M; van Loon, Luc J C

    2011-06-01

    The loss of muscle mass with aging has been, at least partly, attributed to a blunted muscle protein synthetic response to food intake. Leucine coingestion has been reported to stimulate postprandial insulin release and augment postprandial muscle protein accretion. We assessed the clinical benefits of 6 mo of leucine supplementation in elderly, type 2 diabetes patients. Sixty elderly males with type 2 diabetes (age, 71 ± 1 y; BMI, 27.3 ± 0.4 kg/m(2)) were administered 2.5 g L-leucine (n = 30) or a placebo (n = 30) with each main meal during 6 mo of nutritional intervention (7.5 g/d leucine or placebo). Body composition, muscle fiber characteristics, muscle strength, glucose homeostasis, and basal plasma amino acid and lipid concentrations were assessed prior to, during, and after intervention. Lean tissue mass did not change or differ between groups and at 0, 3, and 6 mo were 61.9 ± 1.1, 62.2 ± 1.1, and 62.0 ± 1.0 kg, respectively, in the leucine group and 62.2 ± 1.3, 62.2 ± 1.3, and 62.2 ± 1.3 kg in the placebo group. There also were no changes in body fat percentage, muscle strength, and muscle fiber type characteristics. Blood glycosylated hemoglobin did not change or differ between groups and was 7.1 ± 0.1% in the leucine group and 7.2 ± 0.2% in the placebo group. Consistent with this, oral glucose insulin sensitivity and plasma lipid concentrations did not change or differ between groups. We conclude that prolonged leucine supplementation (7.5 g/d) does not modulate body composition, muscle mass, strength, glycemic control, and/or lipidemia in elderly, type 2 diabetes patients who habitually consume adequate dietary protein. PMID:21525248

  20. Lamotrigine Augmentation Versus Placebo in Serotonin Reuptake Inhibitors-Resistant Obsessive-Compulsive Disorder: A Randomized Controlled Trial

    PubMed Central

    Khalkhali, Mohammadrasoul; Zarrabi, Homa; Kafie, Moosa; Heidarzadeh, Abtin

    2016-01-01

    Objective: Serotonin reuptake inhibitors are frequently used in first-line treatments for patients with obsessive-compulsive disorder. Nevertheless, many of these patients do not respond well to initial therapy. The hypothesis of glutamatergic dysfunction in specific brain regions has been proposed in the pathophysiology of obsessive-compulsive disorder. This study was designed to evaluate the possible efficacy of lamotrigine, a glutamatergic agent in Serotonin reuptake inhibitors-resistant patients with obsessive-compulsive disorder. Method: This study was a 12-week, double blind, randomized, placebo-controlled trial of adjunctive fixed-doses of lamotrigine (100 mg) to Serotonin reuptake inhibitors therapy in obsessive-compulsive disorder. Eligible subjects who had a total Y-BOCS of 21 or above were randomly assigned to receive adjunctive treatment with either lamotrigine (n = 26), or placebo (n = 27). Response to lamotrigine was defined as clinical improvement (>25% decrease in the total Y-BOCS score), which was administered at weeks 0, 8 and 12. Results: At the endpoint (week 12), significant differences were observed in obsession, compulsion, and total Y-BOCS scores comparing lamotrigine to placebo (P = 0.01, 0.005 and 0.007 respectively). The mean reduction in obsession, compulsion and total scores in lamotrigine group was about 4.15, 4.50 and 8.73, respectively. Similarly, the mean reductions in the placebo group were 2.52, 2.56 and 5.07. Effect sizes for efficacy measureswerecalculatedbyCohen’sd, and it was calculated as 0.54 for the total YBOCS. Conclusion: Our findings provide evidence that this augmentation is well tolerated and may be an effective strategy for patients with refractory obsessive-compulsive disorder. PMID:27437007

  1. Controlling Virtual Clouds and Making it Rain Particle Systems in Real Spaces Using Situated Augmented Simulation and Portable Virtual Environments

    NASA Astrophysics Data System (ADS)

    Hedley, N.; Lonergan, C. D.

    2012-07-01

    The research described in this paper reports on the design, rationale, development and implementation of a set of new geospatial interfaces that combine multi-touch interaction, portable virtual environments, 'geosimulation gaming', and mobile augmented reality. The result is a set of new ways for us to combine the capabilities of geospatial virtual environments, augmented realitiy and geosimulation. These new hybrid interfaces deliver new geospatial information experiences - new ways of connecting spatial data, simulations, and abstract concepts to real spaces. Their potential to enhance environmental perception and learning must be explored.

  2. Fetal acidosis and hypotension during repeated umbilical cord occlusions are associated with enhanced chemoreflex responses in near-term fetal sheep.

    PubMed

    Bennet, Laura; Westgate, Jenny A; Liu, Yung-Chi Jack; Wassink, Guido; Gunn, Alistair J

    2005-10-01

    This study examined the hypothesis that repeated episodes of brief but severe hypoxia would not attenuate the chemoreflex-mediated rapid initial fall in fetal heart rate (FHR) and, further, that greater hypoxic stress, as shown by hypotension and metabolic acidosis, would be associated with an enhanced chemoreflex response. Chronically instrumented, near-term fetal sheep received 1 min total umbilical cord occlusion either every 5 min for 4 h (1:5 group; n = 8) or every 2.5 min (1:2.5 group; n = 8) until mean arterial blood pressure fell to <20 mmHg on two successive occlusions. Umbilical cord occlusion caused variable decelerations, with sustained hypertension in the 1:5 group and little change in acid-base status (pH 7.34 +/- 0.03 after 4 h). In contrast, the 1:2.5 group showed progressive hypotension and metabolic acidemia (pH 6.92 +/- 0.04 after the last occlusion). The 1:2.5 group showed a significant increase in the rate of initial fall in FHR during the occlusion series, which was greater than the 1:5 group in the last 30 min of the occlusion series (9.4 +/- 1.4 vs. 3.5 +/- 0.3 beats.min(-1).s(-1); P < 0.01), with a greater fall in FHR (71.9 +/- 6.5 vs. 47.0 +/- 8.7 beats/min; P < 0.05). In summary, this study demonstrated that repetitive laborlike cord occlusions, which led to severe fetal compromise, were associated with an increase in the slope and magnitude of the initial FHR deceleration. These findings support the concept of the chemoreflex as a central, robust component of fetal adaptation to severe hypoxia. PMID:15976361

  3. Risperidone Augmentation for Treatment-Resistant Aggression in Attention-Deficit/Hyperactivity Disorder: A Placebo-Controlled Pilot Study

    ERIC Educational Resources Information Center

    Armenteros, Jorge L.; Lewis, John E.; Davalos, Marisabel

    2007-01-01

    Objective: To evaluate the effects of risperidone augmentation for treatment-resistant aggression in children with attention-deficit/hyperactivity disorder (ADHD). Method: Twenty-five children (ages 7-12 years) with attention-deficit/hyperactivity disorder(ADHD) and significant aggressive behaviors were randomized to risperidone or placebo for 4…

  4. In-Flight Suppression of an Unstable F/A-18 Structural Mode Using the Space Launch System Adaptive Augmenting Control System

    NASA Technical Reports Server (NTRS)

    VanZwieten, Tannen S.; Gilligan, Eric T.; Wall, John H.; Miller, Christopher J.; Hanson, Curtis E.; Orr, Jeb S.

    2015-01-01

    NASA's Space Launch System (SLS) Flight Control System (FCS) includes an Adaptive Augmenting Control (AAC) component which employs a multiplicative gain update law to enhance the performance and robustness of the baseline control system for extreme off-nominal scenarios. The SLS FCS algorithm including AAC has been flight tested utilizing a specially outfitted F/A-18 fighter jet in which the pitch axis control of the aircraft was performed by a Non-linear Dynamic Inversion (NDI) controller, SLS reference models, and the SLS flight software prototype. This paper describes test cases from the research flight campaign in which the fundamental F/A-18 airframe structural mode was identified using post-flight frequency-domain reconstruction, amplified to result in closed loop instability, and suppressed in-flight by the SLS adaptive control system.

  5. In-Flight Suppression of a Destabilized F/A-18 Structural Mode Using the Space Launch System Adaptive Augmenting Control System

    NASA Technical Reports Server (NTRS)

    Wall, John H.; VanZwieten, Tannen S.; Gilligan, Eric T.; Miller, Christopher J.; Hanson, Curtis E.; Orr, Jeb S.

    2015-01-01

    NASA's Space Launch System (SLS) Flight Control System (FCS) includes an Adaptive Augmenting Control (AAC) component which employs a multiplicative gain update law to enhance the performance and robustness of the baseline control system for extreme off nominal scenarios. The SLS FCS algorithm including AAC has been flight tested utilizing a specially outfitted F/A-18 fighter jet in which the pitch axis control of the aircraft was performed by a Non-linear Dynamic Inversion (NDI) controller, SLS reference models, and the SLS flight software prototype. This paper describes test cases from the research flight campaign in which the fundamental F/A-18 airframe structural mode was identified using frequency-domain reconstruction of flight data, amplified to result in closed loop instability, and suppressed in-flight by the SLS adaptive control system.

  6. Randomised controlled trial of labouring in water compared with standard of augmentation for management of dystocia in first stage of labour

    PubMed Central

    Cluett, Elizabeth R; Pickering, Ruth M; Getliffe, Kathryn; Saunders, Nigel James St George

    2004-01-01

    Objectives To evaluate the impact of labouring in water during first stage of labour on rates of epidural analgesia and operative delivery in nulliparous women with dystocia. Design Randomised controlled trial. Setting University teaching hospital in southern England. Participants 99 nulliparous women with dystocia (cervical dilation rate < 1 cm/hour in active labour) at low risk of complications. Interventions Immersion in water in birth pool or standard augmentation for dystocia (amniotomy and intravenous oxytocin). Main outcome measures Primary: epidural analgesia and operative delivery rates. Secondary: augmentation rates with amniotomy and oxytocin, length of labour, maternal and neonatal morbidity including infections, maternal pain score, and maternal satisfaction with care. Results Women randomised to immersion in water had a lower rate of epidural analgesia than women allocated to augmentation (47% v 66%, relative risk 0.71 (95% confidence interval 0.49 to 1.01), number needed to treat for benefit (NNT) 5). They showed no difference in rates of operative delivery (49% v 50%, 0.98 (0.65 to 1.47), NNT 98), but significantly fewer received augmentation (71% v 96%, 0.74 (0.59 to 0.88), NNT 4) or any form of obstetric intervention (amniotomy, oxytocin, epidural, or operative delivery) (80% v 98%, 0.81 (0.67 to 0.92), NNT 5). More neonates of women in the water group were admitted to the neonatal unit (6 v 0, P = 0.013), but there was no difference in Apgar score, infection rates, or umbilical cord pH. Conclusions Labouring in water under midwifery care may be an option for slow progress in labour, reducing the need for obstetric intervention, and offering an alternative pain management strategy. PMID:14744822

  7. The use of the Alexis® device in breast augmentation to improve outcomes: a comparative randomized case-control survey

    PubMed Central

    Dessy, Luca Andrea; Serratore, Francesco; Ribuffo, Diego; Mazzocchi, Marco

    2016-01-01

    Background We present our experience in using a disposable wound retractor commonly used in abdominal surgery named Alexis® (Applied Medical Resources Corporation, Rancho Santa Margarita, CA, USA), during breast augmentation in order to improve outcomes, particularly final scar length. Methods Between January 2010 and November 2012, 40 patients undergoing breast augmentation with an inframammary approach were enrolled in the present study. Patients were randomly assigned to two groups: group 1 underwent breast augmentation with the standard technique; group 2 underwent breast augmentation by using the Alexis® (Applied Medical Resources Corporation) device. Patients were followed-up for a 12-month period. The time of surgery, the days of drain duration and the length of the incisions were recorded for both groups and statistical significance was evaluated with the Wilcoxon rank sum test. Also, final scar appearance was evaluated using a visual analogue scale (VAS). Results Patients in group 2 reported a lower incidence of hematomas and had shorter drain duration. The difference in scar length between the two groups was statistically significant (P<0.05). Surgeons and patients were mostly satisfied with the final appearance of the scar. Conclusions The use of the Alexis® (Applied Medical Resources Corporation) device has proven useful in reducing the length of the inframammary incision. Interestingly, the increased visibility obtained with the use of the Alexis device allowed a better hemostasis, as suggested by the shorter drain duration and lower incidence of hematomas. However, its use prolongs the operative time, for which we recommend surgeons to allow themselves some time to become familiar with the device. Level of evidence: level I, evidence obtained from at least one properly designed randomized controlled trial. PMID:27294035

  8. Augmented Reality Tower Technology Assessment

    NASA Technical Reports Server (NTRS)

    Reisman, Ronald J.; Brown, David M.

    2009-01-01

    Augmented Reality technology may help improve Air Traffic Control Tower efficiency and safety during low-visibility conditions. This paper presents the assessments of five off-duty controllers who shadow-controlled' with an augmented reality prototype in their own facility. Initial studies indicated unanimous agreement that this technology is potentially beneficial, though the prototype used in the study was not adequate for operational use. Some controllers agreed that augmented reality technology improved situational awareness, had potential to benefit clearance, control, and coordination tasks and duties and could be very useful for acquiring aircraft and weather information, particularly aircraft location, heading, and identification. The strongest objections to the prototype used in this study were directed at aircraft registration errors, unacceptable optical transparency, insufficient display performance in sunlight, inadequate representation of the static environment and insufficient symbology.

  9. Effects of Mobile Augmented Reality Learning Compared to Textbook Learning on Medical Students: Randomized Controlled Pilot Study

    PubMed Central

    2013-01-01

    Background By adding new levels of experience, mobile Augmented Reality (mAR) can significantly increase the attractiveness of mobile learning applications in medical education. Objective To compare the impact of the heightened realism of a self-developed mAR blended learning environment (mARble) on learners to textbook material, especially for ethically sensitive subjects such as forensic medicine, while taking into account basic psychological aspects (usability and higher level of emotional involvement) as well as learning outcomes (increased learning efficiency). Methods A prestudy was conducted based on a convenience sample of 10 third-year medical students. The initial emotional status was captured using the “Profile of Mood States” questionnaire (POMS, German variation); previous knowledge about forensic medicine was determined using a 10-item single-choice (SC) test. During the 30-minute learning period, the students were randomized into two groups: the first group consisted of pairs of students, each equipped with one iPhone with a preinstalled copy of mARble, while the second group was provided with textbook material. Subsequently, both groups were asked to once again complete the POMS questionnaire and SC test to measure changes in emotional state and knowledge gain. Usability as well as pragmatic and hedonic qualities of the learning material was captured using AttrakDiff2 questionnaires. Data evaluation was conducted anonymously. Descriptive statistics for the score in total and the subgroups were calculated before and after the intervention. The scores of both groups were tested against each other using paired and unpaired signed-rank tests. An item analysis was performed for the SC test to objectify difficulty and selectivity. Results Statistically significant, the mARble group (6/10) showed greater knowledge gain than the control group (4/10) (Wilcoxon z=2.232, P=.03). The item analysis of the SC test showed a difficulty of P=0.768 (s=0.09) and a

  10. Digital integrated control of a Mach 2.5 mixed-compression supersonic inlet and an augmented mixed-flow turbofan engine

    NASA Technical Reports Server (NTRS)

    Batterton, P. G.; Arpasi, D. J.; Baumbick, R. J.

    1974-01-01

    A digitally implemented integrated inlet-engine control system was designed and tested on a mixed-compression, axisymmetric, Mach 2.5, supersonic inlet with 45 percent internal supersonic area contraction and a TF30-P-3 augmented turbofan engine. The control matched engine airflow to available inlet airflow. By monitoring inlet terminal shock position and over-board bypass door command, the control adjusted engine speed so that in steady state, the shock would be at the desired location and the overboard bypass doors would be closed. During engine-induced transients, such as augmentor light-off and cutoff, the inlet operating point was momentarily changed to a more supercritical point to minimize unstarts. The digital control also provided automatic inlet restart. A variable inlet throat bleed control, based on throat Mach number, provided additional inlet stability margin.

  11. Effective Augmentation of Complex Networks.

    PubMed

    Wang, Jinjian; Yu, Xinghuo; Stone, Lewi

    2016-01-01

    Networks science plays an enormous role in many aspects of modern society from distributing electrical power across nations to spreading information and social networking amongst global populations. While modern networks constantly change in size, few studies have sought methods for the difficult task of optimising this growth. Here we study theoretical requirements for augmenting networks by adding source or sink nodes, without requiring additional driver-nodes to accommodate the change i.e., conserving structural controllability. Our "effective augmentation" algorithm takes advantage of clusters intrinsic to the network topology, and permits rapidly and efficient augmentation of a large number of nodes in one time-step. "Effective augmentation" is shown to work successfully on a wide range of model and real networks. The method has numerous applications (e.g. study of biological, social, power and technological networks) and potentially of significant practical and economic value. PMID:27165120

  12. Tetraplegia is associated with enhanced peripheral chemoreflex sensitivity and ventilatory long-term facilitation

    PubMed Central

    Sankari, Abdulghani; Bascom, Amy T.; Riehani, Anas; Badr, M. Safwan

    2016-01-01

    Cardiorespiratory plasticity induced by acute intermittent hypoxia (AIH) may contribute to recovery following spinal cord injury (SCI). We hypothesized that patients with cervical SCI would demonstrate higher minute ventilation (V̇e) following AIH compared with subjects with thoracic SCI and able-bodied subjects who served as controls. Twenty-four volunteers (8 with cervical SCI, 8 with thoracic SCI, and 8 able-bodied) underwent an AIH protocol during wakefulness. Each subject experienced 15 episodes of isocapnic hypoxia using mixed gases of 100% nitrogen (N2), 8% O2, and 40% CO2 to achieve oxygen saturation ≤90% followed by room air (RA). Measurements were obtained before, during, and 40 min after AIH to obtain ventilation and heart rate variability data [R-R interval (RRI) and low-frequency/ high-frequency power (LF/HF)]. AIH results were compared with those of sham studies conducted in RA during the same time period. Individuals with cervical SCI had higher V̇e after AIH compared with able-bodied controls (117.9 ± 23.2% vs. 97.9 ± 11.2%, P < 0.05). RRI decreased during hypoxia in all individuals (those with cervical SCI, from 1,009.3 ± 65.0 ms to 750.2 ± 65.0 ms; those with thoracic SCI, from 945.2 ± 65.0 ms to 674.9 ± 65.0 ms; and those who were able-bodied, from 949 ± 75.0 to 682.2 ± 69.5 ms; P < 0.05). LH/HF increased during recovery in individuals with thoracic SCI and those who were able-bodied (0.54 ± 0.22 vs. 1.34 ± 0.22 and 0.67 ± 0.23 vs. 1.82 ± 0.23, respectively; P < 0.05) but remained unchanged in the group with cervical SCI. Our conclusion is that patients with cervical SCI demonstrate ventilatory long-term facilitation following AIH compared with able-bodied controls. Heart rate responses to hypoxia are acutely present in patients with cervical SCI but are absent during posthypoxic recovery. PMID:26272316

  13. From Augmentation to Conservation of Entomopathogenic Nematodes: Trophic Cascades, Habitat Manipulation and Enhanced Biological Control of Diaprepes abbreviatus Root Weevils in Florida Citrus Groves

    PubMed Central

    Stuart, R. J.; El-Borai, F. E.; Duncan, L. W.

    2008-01-01

    The use of entomopathogenic nematodes (EPN) for management of the root weevil, Diaprepes abbreviatus, in Florida citrus groves is considered a biological control success story and typically involves augmentation in which EPN are applied inundatively as biopesticides to quickly kill the pest. However, recent evidence indicates that efficacy of EPN applications in Florida citrus depends on soil type. They are very effective in the well drained coarse sands of the Central Ridge but often less so in poorly drained fine-textured soils of the Flatwoods. Moreover, groves on the Central Ridge can harbor rich communities of endemic EPN that might often suppress weevil populations below economic thresholds, whereas Flatwoods groves tend to have few endemic EPN and frequent weevil problems. Current research is examining the ecological dynamics of EPN in Florida citrus groves, the potential impact of EPN augmentation on soil food webs, especially endemic EPN, and whether habitat manipulation and inoculation strategies might be effective for conserving and enhancing EPN communities to achieve long-term control in problem areas. Conservation biological control could extend the usefulness of EPN in Florida citrus and be especially appropriate for groves with persistent weevil problems. PMID:19259523

  14. Consequences of peripheral chemoreflex inhibition with low-dose dopamine in humans

    PubMed Central

    Niewinski, Piotr; Tubek, Stanislaw; Banasiak, Waldemar; Paton, Julian F R; Ponikowski, Piotr

    2014-01-01

    Low-dose dopamine inhibits peripheral chemoreceptors and attenuates the hypoxic ventilatory response (HVR) in humans. However, it is unknown: (1) whether it also modulates the haemodynamic reactions to acute hypoxia, (2) whether it also modulates cardiac baroreflex sensitivity (BRS) and (3) if there is any effect of dopamine withdrawal. We performed a double-blind, placebo-controlled study on 11 healthy male volunteers. At sea level over 2 days every subject was administered low-dose dopamine (2 μg kg–1 min–1) or saline infusion, during which we assessed both ventilatory and haemodynamic responses to acute hypoxia. Separately, we evaluated effects of initiation and withdrawal of each infusion and BRS. The initiation of dopamine infusion did not affect minute ventilation (MV) or mean blood pressure (MAP), but increased both heart rate (HR) and cardiac output. Concomitantly, it decreased systemic vascular resistance. Dopamine blunted the ventilatory, MAP and HR reactions (hypertension, tachycardia) to acute hypoxia. Dopamine attenuated cardiac BRS to falling blood pressure. Dopamine withdrawal evoked an increase in MV. The magnitude of the increment in MV due to dopamine withdrawal correlated with the size of the HVR and depended on the duration of dopamine administration. The ventilatory reaction to dopamine withdrawal constitutes a novel index of peripheral chemoreceptor function. PMID:24396060

  15. Antipsychotic Augmentation of Serotonin Reuptake Inhibitors in Treatment-Resistant Obsessive-Compulsive Disorder: An Update Meta-Analysis of Double-Blind, Randomized, Placebo-Controlled Trials

    PubMed Central

    Dold, Markus; Aigner, Martin; Lanzenberger, Rupert

    2015-01-01

    Background: Many patients with obsessive-compulsive disorder do not respond adequately to serotonin reuptake inhibitors. Augmentation with antipsychotic drugs can be beneficial in this regard. However, since new relevant randomized controlled trials evaluating new antipsychotics were conducted, a recalculation of the effect sizes appears necessary. Methods: We meta-analyzed all double-blind, randomized, placebo-controlled trials comparing augmentation of serotonin reuptake inhibitors with antipsychotics to placebo supplementation in treatment-resistant obsessive-compulsive disorder. The primary outcome was mean change in the Yale-Brown Obsessive–Compulsive Scale total score. Secondary outcomes were obsessions, compulsions, response rates, and attrition rates. The data collection process was conducted independently by 2 authors. Hedges’s g and risks ratios were calculated as effect sizes. In preplanned meta-regressions, subgroup analyses, and sensitivity analyses, we examined the robustness of the results and explored reasons for potential heterogeneity. Results: Altogether, 14 double-blind, randomized, placebo-controlled trials (n=491) investigating quetiapine (N=4, n=142), risperidone (N=4, n=132), aripiprazole (N=2, n=79), olanzapine (N=2, n=70), paliperidone (N=1, n=34), and haloperidol (N=1, n=34) were incorporated. Augmentation with antipsychotics was significantly more efficacious than placebo in Yale-Brown Obsessive–Compulsive Scale total reduction (N=14, n=478; Hedges’s g=-0.64, 95% CI: -0.87 to -0.41; P=<.01). Aripiprazole (Hedges’s g=-1.35), haloperidol (Hedges’s g=-0.82), and risperidone (Hedges’s g=-0.59) significantly outperformed placebo. Antipsychotics were superior to placebo in treating obsessions, compulsions, and achieving response. There was no between-group difference concerning all-cause discontinuation. The nonsignificant meta-regressions suggest no influence of the antipsychotic dose or baseline symptom severity on the meta

  16. Mutually Augmented Cognition

    NASA Astrophysics Data System (ADS)

    Friesdorf, Florian; Pangercic, Dejan; Bubb, Heiner; Beetz, Michael

    In mac, an ergonomic dialog-system and algorithms will be developed that enable human experts and companions to be integrated into knowledge gathering and decision making processes of highly complex cognitive systems (e.g. Assistive Household as manifested further in the paper). In this event we propose to join algorithms and methodologies coming from Ergonomics and Artificial Intelligence that: a) make cognitive systems more congenial for non-expert humans, b) facilitate their comprehension by utilizing a high-level expandable control code for human experts and c) augment representation of such cognitive system into “deep representation” obtained through an interaction with human companions.

  17. Breast augmentation surgery

    MedlinePlus

    Breast augmentation; Breast implants; Implants - breast; Mammaplasty ... Breast augmentation is done by placing implants behind breast tissue or under the chest muscle. An implant is a sac filled with either sterile salt water (saline) or a ...

  18. L1 Adaptive Control Augmentation System with Application to the X-29 Lateral/Directional Dynamics: A Multi-Input Multi-Output Approach

    NASA Technical Reports Server (NTRS)

    Griffin, Brian Joseph; Burken, John J.; Xargay, Enric

    2010-01-01

    This paper presents an L(sub 1) adaptive control augmentation system design for multi-input multi-output nonlinear systems in the presence of unmatched uncertainties which may exhibit significant cross-coupling effects. A piecewise continuous adaptive law is adopted and extended for applicability to multi-input multi-output systems that explicitly compensates for dynamic cross-coupling. In addition, explicit use of high-fidelity actuator models are added to the L1 architecture to reduce uncertainties in the system. The L(sub 1) multi-input multi-output adaptive control architecture is applied to the X-29 lateral/directional dynamics and results are evaluated against a similar single-input single-output design approach.

  19. A placebo-controlled crossover study of iloperidone augmentation for residual anger and irritability in major depressive disorder

    PubMed Central

    Ionescu, Dawn F.; Fava, Maurizio; Kim, Daniel Ju Hyung; Baer, Lee; Shelton, Richard C.; Cusin, Cristina

    2016-01-01

    Background: Even when patients experience remission with antidepressants, many continue to report anger attacks and excessive irritability despite continued treatment. Iloperidone antagonizes 5-HT-2a, D2, and alpha-1 receptors, which can have anti-aggressive effects. We examined iloperidone’s safety and efficacy as an augmentation agent in outpatients with partially remitted major depressive disorder (MDD) with residual symptoms of anger and irritability. Methods: A total of 13 outpatients with partially remitted MDD [currently treated with selective serotonin reuptake inhibitors (SSRIs)] received four weeks of iloperidone or placebo, followed by one week of washout. Patients were then crossed over to the other treatment arm for 4 weeks. Treatment arms were randomized and double blind; and two sites were used for the study. Analyses compared treatment response using the Symptom Questionnaire (SQ) Anger/Hostility Subscale as the primary outcome measure. Results: There was no significant differential effect of iloperidone × weeks on the SQ Anger/Hostility Subscore over the course of the study, compared with placebo × weeks, regardless of administration order (p = 0.77). Conclusions: Iloperidone did not significantly outperform placebo on measures of anger or irritability in patients with partially remitted MDD and residual anger/irritability. PMID:26913173

  20. Status report of RMS active damping augmentation

    NASA Technical Reports Server (NTRS)

    Gilbert, Mike; Demeo, Martha E.

    1993-01-01

    A status report of Remote Manipulator System (RMS) active damping augmentation is presented. Topics covered include: active damping augmentation; benefits of RMS ADA; simulated payload definition; sensor and actuator definition; ADA control law design; Shuttle Engineering Simulator (SES) real-time simulation; and astronaut evaluation.

  1. Augmented Reality for Close Quarters Combat

    ScienceCinema

    None

    2014-06-23

    Sandia National Laboratories has developed a state-of-the-art augmented reality training system for close-quarters combat (CQB). This system uses a wearable augmented reality system to place the user in a real environment while engaging enemy combatants in virtual space (Boston Dynamics DI-Guy). Umbra modeling and simulation environment is used to integrate and control the AR system.

  2. Augmented Reality for Close Quarters Combat

    SciTech Connect

    2013-09-20

    Sandia National Laboratories has developed a state-of-the-art augmented reality training system for close-quarters combat (CQB). This system uses a wearable augmented reality system to place the user in a real environment while engaging enemy combatants in virtual space (Boston Dynamics DI-Guy). Umbra modeling and simulation environment is used to integrate and control the AR system.

  3. Components of a Rice-Oilseed Rape Production System Augmented with Trichoderma sp. Tri-1 Control Sclerotinia sclerotiorum on Oilseed Rape.

    PubMed

    Hu, Xiaojia; Roberts, Daniel P; Xie, Lihua; Maul, Jude E; Yu, Changbing; Li, Yinshui; Zhang, Yinbo; Qin, Lu; Liao, Xing

    2015-10-01

    Sclerotinia sclerotiorum causes serious yield losses on many crops throughout the world. A multicomponent treatment that consisted of the residual rice straw remaining after rice harvest and Trichoderma sp. Tri-1 (Tri-1) formulated with the oilseed rape seedcake fertilizer was used in field soil infested with S. sclerotiorum. This treatment resulted in oilseed rape seed yield that was significantly greater than the nontreated control or when the fungicide carbendizem was used in the presence of this pathogen in field trials. Yield data suggested that the rice straw, oilseed rape seedcake, and Tri-1 components of this treatment all contributed incrementally. Similar treatment results were obtained regarding reduction in disease incidence. Slight improvements in yield and disease incidence were detected when this multicomponent treatment was combined with a fungicide spray. Inhibition of sclerotial germination by this multicomponent treatment trended greater than the nontreated control at 90, 120, and 150 days in field studies but was not significantly different from this control. This multicomponent treatment resulted in increased yield relative to the nontreated control in the absence of pathogen in a greenhouse pot study, while the straw alone and the straw plus oilseed rape seedcake treatments did not; suggesting that Tri-1 was capable of promoting growth. Experiments reported here indicate that a treatment containing components of a rice-oilseed rape production system augmented with Tri-1 can control S. sclerotiorum on oilseed rape, be used in integrated strategies containing fungicide sprays for control of this pathogen, and promote plant growth. PMID:26390095

  4. Gluteal augmentation with cryopreserved fat.

    PubMed

    Moscatiello, Fabrizio; Aznar-Benitah, Salvador; Grella, Roberto; Jover, Javier Herrero

    2010-03-01

    Gluteal augmentation with autologous fat is becoming a standard ancillary procedure for sculpting the buttock area. The high rate of resorption due to aggressive harvesting techniques or inadequate injection procedures often leads to repeated treatments. Currently, several techniques for storing fat by controlled freezing and thawing procedures can guarantee a high rate of cell viability, similar to that obtained with fresh tissue. This allows surgeons to compile fat tissue available for future repeat injections, decreasing additional costs and morbidity for patients. The authors describe a case of gluteal augmentation with cryopreserved fat in a 42-year-old man. PMID:20442098

  5. Membranes and Bone Substitutes in a One-Stage Procedure for Horizontal Bone Augmentation: A Histologic Double-Blind Parallel Randomized Controlled Trial.

    PubMed

    Merli, Mauro; Moscatelli, Marco; Mariotti, Giorgia; Pagliaro, Umberto; Breschi, Lorenzo; Mazzoni, Annalisa; Nieri, Michele

    2015-01-01

    The aim of this histologic, double-blind, parallel, randomized controlled trial was to compare anorganic bone mineral-collagen membranes (BB) and betatricalcium phosphate-pericardium collagen membranes (CJ) in a one-stage procedure for horizontal bone augmentation. A biopsy was performed in the regenerated area at abutment connection 6 months after surgery. Five patients were assigned and treated with the BB combination and five patients were treated with the CJ combination. At abutment connection, 6 months after grafting, no significant differences were evident in the histomorphometric comparisons, even if the percentage of residual graft, using the marrow spaces and soft tissue as a reference, tended to be greater in the CJ group (P = .0759). PMID:26133135

  6. Experimental Investigation of Augmented Spark Ignition of a LO2/LCH4 Reaction Control Engine at Altitude Conditions

    NASA Technical Reports Server (NTRS)

    Kleinhenz, Julie; Sarmiento, Charles; Marshall, William

    2012-01-01

    The use of nontoxic propellants in future exploration vehicles would enable safer, more cost-effective mission scenarios. One promising green alternative to existing hypergols is liquid methane (LCH4) with liquid oxygen (LO2). A 100 lbf LO2/LCH4 engine was developed under the NASA Propulsion and Cryogenic Advanced Development project and tested at the NASA Glenn Research Center Altitude Combustion Stand in a low pressure environment. High ignition energy is a perceived drawback of this propellant combination; so this ignition margin test program examined ignition performance versus delivered spark energy. Sensitivity of ignition to spark timing and repetition rate was also explored. Three different exciter units were used with the engine s augmented (torch) igniter. Captured waveforms indicated spark behavior in hot fire conditions was inconsistent compared to the well-behaved dry sparks. This suggests that rising pressure and flow rate increase spark impedance and may at some point compromise an exciter s ability to complete each spark. The reduced spark energies of such quenched deliveries resulted in more erratic ignitions, decreasing ignition probability. The timing of the sparks relative to the pressure/flow conditions also impacted the probability of ignition. Sparks occurring early in the flow could trigger ignition with energies as low as 1 to 6 mJ, though multiple, similarly timed sparks of 55 to 75 mJ were required for reliable ignition. Delayed spark application and reduced spark repetition rate both correlated with late and occasional failed ignitions. An optimum time interval for spark application and ignition therefore coincides with propellant introduction to the igniter.

  7. Augmented Reality in astrophysics

    NASA Astrophysics Data System (ADS)

    Vogt, Frédéric P. A.; Shingles, Luke J.

    2013-09-01

    Augmented Reality consists of merging live images with virtual layers of information. The rapid growth in the popularity of smartphones and tablets over recent years has provided a large base of potential users of Augmented Reality technology, and virtual layers of information can now be attached to a wide variety of physical objects. In this article, we explore the potential of Augmented Reality for astrophysical research with two distinct experiments: (1) Augmented Posters and (2) Augmented Articles. We demonstrate that the emerging technology of Augmented Reality can already be used and implemented without expert knowledge using currently available apps. Our experiments highlight the potential of Augmented Reality to improve the communication of scientific results in the field of astrophysics. We also present feedback gathered from the Australian astrophysics community that reveals evidence of some interest in this technology by astronomers who experimented with Augmented Posters. In addition, we discuss possible future trends for Augmented Reality applications in astrophysics, and explore the current limitations associated with the technology. This Augmented Article, the first of its kind, is designed to allow the reader to directly experiment with this technology.

  8. Augmented reality system

    NASA Astrophysics Data System (ADS)

    Lin, Chien-Liang; Su, Yu-Zheng; Hung, Min-Wei; Huang, Kuo-Cheng

    2010-08-01

    In recent years, Augmented Reality (AR)[1][2][3] is very popular in universities and research organizations. The AR technology has been widely used in Virtual Reality (VR) fields, such as sophisticated weapons, flight vehicle development, data model visualization, virtual training, entertainment and arts. AR has characteristics to enhance the display output as a real environment with specific user interactive functions or specific object recognitions. It can be use in medical treatment, anatomy training, precision instrument casting, warplane guidance, engineering and distance robot control. AR has a lot of vantages than VR. This system developed combines sensors, software and imaging algorithms to make users feel real, actual and existing. Imaging algorithms include gray level method, image binarization method, and white balance method in order to make accurate image recognition and overcome the effects of light.

  9. Augmentation-related brain plasticity.

    PubMed

    Di Pino, Giovanni; Maravita, Angelo; Zollo, Loredana; Guglielmelli, Eugenio; Di Lazzaro, Vincenzo

    2014-01-01

    Today, the anthropomorphism of the tools and the development of neural interfaces require reconsidering the concept of human-tools interaction in the framework of human augmentation. This review analyses the plastic process that the brain undergoes when it comes into contact with augmenting artificial sensors and effectors and, on the other hand, the changes that the use of external augmenting devices produces in the brain. Hitherto, few studies investigated the neural correlates of augmentation, but clues on it can be borrowed from logically-related paradigms: sensorimotor training, cognitive enhancement, cross-modal plasticity, sensorimotor functional substitution, use and embodiment of tools. Augmentation modifies function and structure of a number of areas, i.e., primary sensory cortices shape their receptive fields to become sensitive to novel inputs. Motor areas adapt the neuroprosthesis representation firing-rate to refine kinematics. As for normal motor outputs, the learning process recruits motor and premotor cortices and the acquisition of proficiency decreases attentional recruitment, focuses the activity on sensorimotor areas and increases the basal ganglia drive on the cortex. Augmentation deeply relies on the frontoparietal network. In particular, premotor cortex is involved in learning the control of an external effector and owns the tool motor representation, while the intraparietal sulcus extracts its visual features. In these areas, multisensory integration neurons enlarge their receptive fields to embody supernumerary limbs. For operating an anthropomorphic neuroprosthesis, the mirror system is required to understand the meaning of the action, the cerebellum for the formation of its internal model and the insula for its interoception. In conclusion, anthropomorphic sensorized devices can provide the critical sensory afferences to evolve the exploitation of tools through their embodiment, reshaping the body representation and the sense of the self

  10. Augmentation-related brain plasticity

    PubMed Central

    Di Pino, Giovanni; Maravita, Angelo; Zollo, Loredana; Guglielmelli, Eugenio; Di Lazzaro, Vincenzo

    2014-01-01

    Today, the anthropomorphism of the tools and the development of neural interfaces require reconsidering the concept of human-tools interaction in the framework of human augmentation. This review analyses the plastic process that the brain undergoes when it comes into contact with augmenting artificial sensors and effectors and, on the other hand, the changes that the use of external augmenting devices produces in the brain. Hitherto, few studies investigated the neural correlates of augmentation, but clues on it can be borrowed from logically-related paradigms: sensorimotor training, cognitive enhancement, cross-modal plasticity, sensorimotor functional substitution, use and embodiment of tools. Augmentation modifies function and structure of a number of areas, i.e., primary sensory cortices shape their receptive fields to become sensitive to novel inputs. Motor areas adapt the neuroprosthesis representation firing-rate to refine kinematics. As for normal motor outputs, the learning process recruits motor and premotor cortices and the acquisition of proficiency decreases attentional recruitment, focuses the activity on sensorimotor areas and increases the basal ganglia drive on the cortex. Augmentation deeply relies on the frontoparietal network. In particular, premotor cortex is involved in learning the control of an external effector and owns the tool motor representation, while the intraparietal sulcus extracts its visual features. In these areas, multisensory integration neurons enlarge their receptive fields to embody supernumerary limbs. For operating an anthropomorphic neuroprosthesis, the mirror system is required to understand the meaning of the action, the cerebellum for the formation of its internal model and the insula for its interoception. In conclusion, anthropomorphic sensorized devices can provide the critical sensory afferences to evolve the exploitation of tools through their embodiment, reshaping the body representation and the sense of the self

  11. Systems development of a stall/spin research facility using remotely controlled/augmented aircraft models. Volume 1: Systems overview

    NASA Technical Reports Server (NTRS)

    Montoya, R. J.; Jai, A. R.; Parker, C. D.

    1979-01-01

    A ground based, general purpose, real time, digital control system simulator (CSS) is specified, developed, and integrated with the existing instrumentation van of the testing facility. This CSS is built around a PDP-11/55, and its operational software was developed to meet the dual goal of providing the immediate capability to represent the F-18 drop model control laws and the flexibility for expansion to represent more complex control laws typical of control configured vehicles. Overviews of the two CSS's developed are reviewed as well as the overall system after their integration with the existing facility. Also the latest version of the F-18 drop model control laws (REV D) is described and the changes needed for its incorporation in the digital and analog CSS's are discussed.

  12. Development and Flight Test of an Augmented Thrust-Only Flight Control System on an MD-11 Transport Airplane

    NASA Technical Reports Server (NTRS)

    Burcham, Frank W., Jr.; Maine, Trindel A.; Burken, John J.; Pappas, Drew

    1996-01-01

    An emergency flight control system using only engine thrust, called Propulsion-Controlled Aircraft (PCA), has been developed and flight tested on an MD-11 airplane. In this thrust-only control system, pilot flight path and track commands and aircraft feedback parameters are used to control the throttles. The PCA system was installed on the MD-11 airplane using software modifications to existing computers. Flight test results show that the PCA system can be used to fly to an airport and safely land a transport airplane with an inoperative flight control system. In up-and-away operation, the PCA system served as an acceptable autopilot capable of extended flight over a range of speeds and altitudes. The PCA approaches, go-arounds, and three landings without the use of any non-nal flight controls have been demonstrated, including instrument landing system-coupled hands-off landings. The PCA operation was used to recover from an upset condition. In addition, PCA was tested at altitude with all three hydraulic systems turned off. This paper reviews the principles of throttles-only flight control; describes the MD-11 airplane and systems; and discusses PCA system development, operation, flight testing, and pilot comments.

  13. An Experimental Evaluation of Generalized Predictive Control for Tiltrotor Aeroelastic Stability Augmentation in Airplane Mode of Flight

    NASA Technical Reports Server (NTRS)

    Kvaternik, Raymond G.; Piatak, David J.; Nixon, Mark W.; Langston, Chester W.; Singleton, Jeffrey D.; Bennett, Richard L.; Brown, Ross K.

    2001-01-01

    The results of a joint NASA/Army/Bell Helicopter Textron wind-tunnel test to assess the potential of Generalized Predictive Control (GPC) for actively controlling the swashplate of tiltrotor aircraft to enhance aeroelastic stability in the airplane mode of flight are presented. GPC is an adaptive time-domain predictive control method that uses a linear difference equation to describe the input-output relationship of the system and to design the controller. The test was conducted in the Langley Transonic Dynamics Tunnel using an unpowered 1/5-scale semispan aeroelastic model of the V-22 that was modified to incorporate a GPC-based multi-input multi-output control algorithm to individually control each of the three swashplate actuators. Wing responses were used for feedback. The GPC-based control system was highly effective in increasing the stability of the critical wing mode for all of the conditions tested, without measurable degradation of the damping in the other modes. The algorithm was also robust with respect to its performance in adjusting to rapid changes in both the rotor speed and the tunnel airspeed.

  14. V-TIME: a treadmill training program augmented by virtual reality to decrease fall risk in older adults: study design of a randomized controlled trial

    PubMed Central

    2013-01-01

    Background Recent work has demonstrated that fall risk can be attributed to cognitive as well as motor deficits. Indeed, everyday walking in complex environments utilizes executive function, dual tasking, planning and scanning, all while walking forward. Pilot studies suggest that a multi-modal intervention that combines treadmill training to target motor function and a virtual reality obstacle course to address the cognitive components of fall risk may be used to successfully address the motor-cognitive interactions that are fundamental for fall risk reduction. The proposed randomized controlled trial will evaluate the effects of treadmill training augmented with virtual reality on fall risk. Methods/Design Three hundred older adults with a history of falls will be recruited to participate in this study. This will include older adults (n=100), patients with mild cognitive impairment (n=100), and patients with Parkinson’s disease (n=100). These three sub-groups will be recruited in order to evaluate the effects of the intervention in people with a range of motor and cognitive deficits. Subjects will be randomly assigned to the intervention group (treadmill training with virtual reality) or to the active-control group (treadmill training without virtual reality). Each person will participate in a training program set in an outpatient setting 3 times per week for 6 weeks. Assessments will take place before, after, and 1 month and 6 months after the completion of the training. A falls calendar will be kept by each participant for 6 months after completing the training to assess fall incidence (i.e., the number of falls, multiple falls and falls rate). In addition, we will measure gait under usual and dual task conditions, balance, community mobility, health related quality of life, user satisfaction and cognitive function. Discussion This randomized controlled trial will demonstrate the extent to which an intervention that combines treadmill training augmented

  15. Use of the Charge/Discharge (C/D) ratio to augment voltage limit (V sub T) charge control in the ERBS spacecraft

    NASA Astrophysics Data System (ADS)

    Halpert, G.

    1982-07-01

    A 50-ampere hour nickel cadmium cell test pack was operated in a power profile simulating the orbit of the Earth Radiation Budget Satellite (ERBS). The objective was to determine the ability of the temperature compensated voltage limit (V sub T) charge control system to maintain energy balance in the half sine wave-type current profile expected of this mission. The four-cell pack (50 E) was tested at the Naval Weapons Support Center (NWSC) at Crane, Indiana. The ERBS evaluation test consisted of two distinct operating sequences, each having a specific purpose. The first phase was a parametric test involving the effect of V sub T level, temperature, and Beta angle on the charge/discharge (C/D) ratio, an indicator of the amount of overcharge. The second phase of testing made use of the C/D ratio limit to augment the V sub T charge limit control. When the C/D limit was reached, the current was switched from the taper mode to a C/67 (0.75 A) trickle charge. The use of an ampere hour integrator limiting the overcharge to a C/67 rate provided a fine tuning of the charge control technique which eliminated the sensitivity problems noted in the initial operating sequence.

  16. Informatics in radiology: Intuitive user interface for 3D image manipulation using augmented reality and a smartphone as a remote control.

    PubMed

    Nakata, Norio; Suzuki, Naoki; Hattori, Asaki; Hirai, Naoya; Miyamoto, Yukio; Fukuda, Kunihiko

    2012-01-01

    Although widely used as a pointing device on personal computers (PCs), the mouse was originally designed for control of two-dimensional (2D) cursor movement and is not suited to complex three-dimensional (3D) image manipulation. Augmented reality (AR) is a field of computer science that involves combining the physical world and an interactive 3D virtual world; it represents a new 3D user interface (UI) paradigm. A system for 3D and four-dimensional (4D) image manipulation has been developed that uses optical tracking AR integrated with a smartphone remote control. The smartphone is placed in a hard case (jacket) with a 2D printed fiducial marker for AR on the back. It is connected to a conventional PC with an embedded Web camera by means of WiFi. The touch screen UI of the smartphone is then used as a remote control for 3D and 4D image manipulation. Using this system, the radiologist can easily manipulate 3D and 4D images from computed tomography and magnetic resonance imaging in an AR environment with high-quality image resolution. Pilot assessment of this system suggests that radiologists will be able to manipulate 3D and 4D images in the reading room in the near future. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.324115086/-/DC1. PMID:22556316

  17. Flight Test Comparison of Different Adaptive Augmentations for Fault Tolerant Control Laws for a Modified F-15

    NASA Technical Reports Server (NTRS)

    Burken, John J.; Hanson, Curtis E.; Lee, James A.; Kaneshinge, John T.

    2009-01-01

    This report describes the improvements and enhancements to a neural network based approach for directly adapting to aerodynamic changes resulting from damage or failures. This research is a follow-on effort to flight tests performed on the NASA F-15 aircraft as part of the Intelligent Flight Control System research effort. Previous flight test results demonstrated the potential for performance improvement under destabilizing damage conditions. Little or no improvement was provided under simulated control surface failures, however, and the adaptive system was prone to pilot-induced oscillations. An improved controller was designed to reduce the occurrence of pilot-induced oscillations and increase robustness to failures in general. This report presents an analysis of the neural networks used in the previous flight test, the improved adaptive controller, and the baseline case with no adaptation. Flight test results demonstrate significant improvement in performance by using the new adaptive controller compared with the previous adaptive system and the baseline system for control surface failures.

  18. Revision Breast Augmentation at the Time of Cardiac Sarcoma Resection: The Importance of Pocket Control When Inframammary Approach Is Combined with Simultaneous Sternotomy.

    PubMed

    Rose, Jessica F; Kim, Min P; Reardon, Michael J; Ellsworth, Warren A

    2016-03-01

    Sternotomy in patients with previous breast augmentation becomes an aesthetic challenge when an inframammary approach is utilized over the traditional midline skin incision. Although the inframammary fold approach offers a well-concealed scar when compared with the midline chest incision, patients with a history of previous breast augmentation are at risk for alteration of the anatomy leading to symmastia, implant malposition, and asymmetry. We present a case report of sternotomy and resection of a mediastinal perivascular epithelioid cell tumor with concomitant revision augmentation with silicone implants and SERI Scaffold. Our patient had an uncomplicated postoperative course and a good cosmetic result 1 year after concomitant revision augmentation in conjunction with cardiac tumor resection. In conclusion, the authors feel that despite the difficulties in performing breast augmentation in patients undergoing thoracic surgery, it is possible to obtain good results. It is necessary to reinforce the repair with a mesh to recreate support and proper anatomy. PMID:27257577

  19. Revision Breast Augmentation at the Time of Cardiac Sarcoma Resection: The Importance of Pocket Control When Inframammary Approach Is Combined with Simultaneous Sternotomy

    PubMed Central

    Rose, Jessica F.; Kim, Min P.; Reardon, Michael J.

    2016-01-01

    Summary: Sternotomy in patients with previous breast augmentation becomes an aesthetic challenge when an inframammary approach is utilized over the traditional midline skin incision. Although the inframammary fold approach offers a well-concealed scar when compared with the midline chest incision, patients with a history of previous breast augmentation are at risk for alteration of the anatomy leading to symmastia, implant malposition, and asymmetry. We present a case report of sternotomy and resection of a mediastinal perivascular epithelioid cell tumor with concomitant revision augmentation with silicone implants and SERI Scaffold. Our patient had an uncomplicated postoperative course and a good cosmetic result 1 year after concomitant revision augmentation in conjunction with cardiac tumor resection. In conclusion, the authors feel that despite the difficulties in performing breast augmentation in patients undergoing thoracic surgery, it is possible to obtain good results. It is necessary to reinforce the repair with a mesh to recreate support and proper anatomy. PMID:27257577

  20. Making Self-Help More Helpful: A Randomized Controlled Trial of the Impact of Augmenting Self-Help Materials with Implementation Intentions on Promoting the Effective Self-Management of Anxiety Symptoms

    ERIC Educational Resources Information Center

    Varley, Rachel; Webb, Thomas L.; Sheeran, Paschal

    2011-01-01

    Objective: The effectiveness of self-help materials may be constrained by failures to undertake recommended exercises or to deploy the techniques that one has learned at the critical moment. The present randomized controlled trial investigated whether augmenting self-help materials with if-then plans (or implementation intentions) could overcome…

  1. Confronting an Augmented Reality

    ERIC Educational Resources Information Center

    Munnerley, Danny; Bacon, Matt; Wilson, Anna; Steele, James; Hedberg, John; Fitzgerald, Robert

    2012-01-01

    How can educators make use of augmented reality technologies and practices to enhance learning and why would we want to embrace such technologies anyway? How can an augmented reality help a learner confront, interpret and ultimately comprehend reality itself ? In this article, we seek to initiate a discussion that focuses on these questions, and…

  2. Equating of Augmented Subscores

    ERIC Educational Resources Information Center

    Sinharay, Sandip; Haberman, Shelby J.

    2011-01-01

    Recently, there has been an increasing level of interest in subscores for their potential diagnostic value. Haberman (2008b) suggested reporting an augmented subscore that is a linear combination of a subscore and the total score. Sinharay and Haberman (2008) and Sinharay (2010) showed that augmented subscores often lead to more accurate…

  3. Subfascial gluteal augmentation.

    PubMed

    de la Peña, J Abel; Rubio, Omar V; Cano, Jacobo P; Cedillo, Mariana C; Garcés, Miriam T

    2006-07-01

    Developing the concept of gluteal augmentation through the past 17 years has been an academic adventure. During these years my coworkers and I have progressively improved surgical technique and devised an anatomical system for gluteal augmentation that includes an ideal implant design and templates to assist in evaluating patients in the preoperative period and to identify the most appropriate implant size. PMID:16818097

  4. Pre-Diabetes Augments Neuropeptide Y1- and α1-Receptor Control of Basal Hindlimb Vascular Tone in Young ZDF Rats

    PubMed Central

    Novielli, Nicole M.; Al-Khazraji, Baraa K.; Medeiros, Philip J.; Goldman, Daniel; Jackson, Dwayne N.

    2012-01-01

    Background Peripheral vascular disease in pre-diabetes may involve altered sympathetically-mediated vascular control. Thus, we investigated if pre-diabetes modifies baseline sympathetic Y1-receptor (Y1R) and α1-receptor (α1R) control of hindlimb blood flow (Qfem) and vascular conductance (VC). Methods Qfem and VC were measured in pre-diabetic ZDF rats (PD) and lean controls (CTRL) under infusion of BIBP3226 (Y1R antagonist), prazosin (α1R antagonist) and BIBP3226+prazosin. Neuropeptide Y (NPY) concentration and Y1R and α1R expression were determined from hindlimb skeletal muscle samples. Results Baseline Qfem and VC were similar between groups. Independent infusions of BIBP3226 and prazosin led to increases in Qfem and VC in CTRL and PD, where responses were greater in PD (p<0.05). The percent change in VC following both drugs was also greater in PD compared to CTRL (p<0.05). As well, Qfem and VC responses to combined blockade (BIBP3226+prazosin) were greater in PD compared to CTRL (p<0.05). Interestingly, an absence of synergistic effects was observed within groups, as the sum of the VC responses to independent drug infusions was similar to responses following combined blockade. Finally, white and red vastus skeletal muscle NPY concentration, Y1R expression and α1R expression were greater in PD compared to CTRL. Conclusions For the first time, we report heightened baseline Y1R and α1R sympathetic control of Qfem and VC in pre-diabetic ZDF rats. In support, our data suggest that augmented sympathetic ligand and receptor expression in pre-diabetes may contribute to vascular dysregulation. PMID:23071607

  5. Gender-Specific Effects of an Augmented Written Emotional Disclosure Intervention on Posttraumatic, Depressive, and HIV-Disease-Related Outcomes: A Randomized, Controlled Trial

    PubMed Central

    Ironson, Gail; O’Cleirigh, Conall; Leserman, Jane; Stuetzle, Rick; Fordiani, Joanne; Fletcher, MaryAnn; Schneiderman, Neil

    2015-01-01

    Objective Trauma histories and symptoms of PTSD occur at very high rates in people with HIV and are associated with poor disease management and accelerated disease progression. The authors of this study examined the efficacy of a brief written trauma disclosure intervention on posttraumatic stress, depression, HIV-related physical symptoms, and biological markers of HIV disease progression. Method HIV-infected men and women were randomized to four 30-min expressive writing sessions in either a treatment (trauma writing) or an attention control (daily events writing) condition. The disclosure intervention augmented the traditional emotional disclosure paradigm with probes to increase processing by focusing on trauma appraisals, self-worth, and problem solving. Outcomes were assessed at baseline, 1-, 6-, and 12-month follow-up. Results Hierarchical linear modeling (N = 244, intent-to-treat analyses) revealed no significant treatment effects for the group as a whole. Gender by treatment group interactions were significant such that women in the trauma-writing group had significantly reduced posttraumatic stress disorder (PTSD) symptoms (p = .017), depression (p = .009), and HIV-related symptoms (p = .022) compared with their controls. In contrast, men in the trauma-treatment condition did not improve more than controls on any outcome variables. Unexpectedly, men in the daily-event-writing control group had significantly greater reductions in depression then men in the trauma-writing group. Treatment effects were magnified in women when the analysis was restricted to those with elevated PTSD symptoms at baseline. Conclusions A brief (4-session) guided written emotional disclosure intervention resulted in significant and meaningful reductions in PTSD, depression, and physical symptoms for women with HIV, but not for men. PMID:23244367

  6. Intermittent daytime mouthpiece ventilation successfully augments nocturnal non-invasive ventilation, controlling ventilatory failure and maintaining patient independence.

    PubMed

    Ward, Karen; Ford, Verity; Ashcroft, Helen; Parker, Robert

    2015-01-01

    A 53-year-old woman with spinal muscular atrophy and a 7-year history of nocturnal non-invasive ventilation (NIV) use via nasal mask and chinstrap was admitted electively. Outpatient review suggested symptomatic hypercapnia and hypoxaemia. Use of her usual NIV resulted in early morning respiratory acidosis due to excess mouth leak, and continuous face mask NIV was instigated while in hospital. Once stabilised, she elected to return to nasal ventilation. At outpatient review, respiratory acidosis reoccurred despite diurnal use of NIV. Using the patient's routine ventilator and a novel mouthpiece and trigger algorithm, intermittent daytime mouthpiece ventilation (MPV) was introduced alongside overnight NIV. Control of respiratory failure was achieved and, vitally, independent living maintained. Intermittent MPV was practicable and effective where the limits of ventilator tolerance had otherwise been reached. MPV may reduce the need for tracheostomy ventilation and this case serves as a reminder of the increasing options routinely available to NIV clinicians. PMID:26160549

  7. The Effect of Continuous and Discretized Presentations of Concurrent Augmented Visual Biofeedback on Postural Control in Quiet Stance

    PubMed Central

    D’Anna, Carmen; Schmid, Maurizio; Bibbo, Daniele; Bertollo, Maurizio; Comani, Silvia; Conforto, Silvia

    2015-01-01

    The purpose of this study was to evaluate the effect of a continuous and a discretized Visual Biofeedback (VBF) on balance performance in upright stance. The coordinates of the Centre of Pressure (CoP), extracted from a force plate, were processed in real-time to implement the two VBFs, administered to two groups of 12 healthy participants. In the first group, a representation of the CoP was continuously shown, while in the second group, the discretized VBF was provided at an irregular frequency (that depended on the subject's performance) by displaying one out of a set of five different emoticons, each corresponding to a specific area covered by the current position of the CoP. In the first case, participants were asked to maintain a white spot within a given square area, whereas in the second case they were asked to keep the smiling emoticon on. Trials with no VBF were administered as control. The effect of the two VBFs on balance was studied through classical postural parameters and a subset of stabilogram diffusion coefficients. To quantify the amount of time spent in stable conditions, the percentage of time during which the CoP was inside the stability area was calculated. Both VBFs improved balance maintainance as compared to the absence of any VBF. As compared to the continuous VBF, in the discretized VBF a significant decrease of sway path, diffusion and Hurst coefficients was found. These results seem to indicate that a discretized VBF favours a more natural postural behaviour by promoting a natural intermittent postural control strategy. PMID:26196518

  8. High-dose galantamine augmentation inferior to placebo on attention, inhibitory control and working memory performance in nonsmokers with schizophrenia.

    PubMed

    Dyer, Michael A; Freudenreich, Oliver; Culhane, Melissa A; Pachas, Gladys N; Deckersbach, Thilo; Murphy, Erin; Goff, Donald C; Evins, A Eden

    2008-07-01

    Dysfunction in the neuronal nicotinic acetylcholine receptor (nAChR) system has been implicated in the pathophysiology of schizophrenia, and it has been postulated that treatments that increase nAChR activity may improve symptoms of the disorder. We investigated the effects of the acetylcholinesterase inhibitor and allosteric nAChR modulator, galantamine, on cognitive performance and clinical symptoms when added to a stable antipsychotic medication regimen in nonsmoking outpatients with schizophrenia in a double-blind, placebo-controlled, parallel-group design. Participants were randomized to receive either galantamine (n=10) up to 32 mg/day or identical placebo (n=10) for 8 weeks and completed a cognitive battery at baseline and week 8 and clinical scales at baseline, week 4 and week 8. The primary outcome measure was attentional performance as measured by the d' measure in the Continuous Performance Test - Identical Pairs (CPT-IP) Version. Contrary to our hypothesis, galantamine treatment was associated with inferior performance on the CPT-IP, on the three-card Stroop task, and on the Letter-Number Span task without reordering. Galantamine had no effect on clinical symptoms. In summary, galantamine treatment, at a dose of 32 mg/day, was well tolerated but was not effective as an adjunctive treatment for cognitive deficits in stable nonsmokers with schizophrenia. PMID:18325740

  9. Augmented reality: a review.

    PubMed

    Berryman, Donna R

    2012-01-01

    Augmented reality is a technology that overlays digital information on objects or places in the real world for the purpose of enhancing the user experience. It is not virtual reality, that is, the technology that creates a totally digital or computer created environment. Augmented reality, with its ability to combine reality and digital information, is being studied and implemented in medicine, marketing, museums, fashion, and numerous other areas. This article presents an overview of augmented reality, discussing what it is, how it works, its current implementations, and its potential impact on libraries. PMID:22559183

  10. Ziprasidone Augmentation of Escitalopram for Major Depressive Disorder: Efficacy Results from a Randomized, Double-Blind, Placebo-Controlled Study

    PubMed Central

    Papakostas, George I.; Fava, Maurizio; Baer, Lee; Swee, Michaela B.; Jaeger, Adrienne; Bobo, William V.; Shelton, Richard C.

    2016-01-01

    Objective To test the efficacy of adjunctive ziprasidone in adults with non-psychotic unipolar major depression experiencing persistent symptoms following 8 weeks of open-label escitalopram. Method This was a multi-center, parallel randomized, double-blind, placebo-controlled trial conducted at three academic medical centers in the United States. The participant pool consisted of 139 outpatients with persistent symptoms of major depressive disorder following an 8-week open label trial of escitalopram (phase 1). Subjects were randomized (1:1, n=139) to adjunctive ziprasidone (escitalopram+ziprasidone, n=71) or adjunctive placebo (escitalopram+placebo, n=68), with 8 weekly follow-up assessments. Primary outcome was defined by clinical response according to the 17-item Hamilton Depression Rating Scale (HAMD-17) and determined by a 50% or greater reduction in scale scores. The Hamilton Anxiety Rating scale (HAM-A) and Visual Analogue Scale for Pain were defined a priori as key secondary outcome measures. Results Rates of clinical response (35.2% vs. 20.5%, p=0.04) and mean improvement in HAMD-17 total scores (−6.4 ± 6.4 vs. −3.3 ± 6.2, p=0.04) were significantly greater for the escitalopram+ziprasidone group. Several secondary measures of antidepressant efficacy were also in favor of adjunctive ziprasidone. Escitalopram+ziprasidone also resulted in significantly greater improvement in HAM-A, but not Visual Analogue Scale for Pain scores. Ten (14%) patients discontinued escitalopram+ziprasidone due to intolerance versus none for escitalopram+placebo (p<0.01 versus placebo). Conclusions Adjunctive ziprasidone, when added to escitalopram, demonstrated antidepressant efficacy in adult patients with major depressive disorder experiencing persistent symptoms following 8 weeks of open-label escitalopram. PMID:26085041

  11. Effective Augmentation of Complex Networks

    NASA Astrophysics Data System (ADS)

    Wang, Jinjian; Yu, Xinghuo; Stone, Lewi

    2016-05-01

    Networks science plays an enormous role in many aspects of modern society from distributing electrical power across nations to spreading information and social networking amongst global populations. While modern networks constantly change in size, few studies have sought methods for the difficult task of optimising this growth. Here we study theoretical requirements for augmenting networks by adding source or sink nodes, without requiring additional driver-nodes to accommodate the change i.e., conserving structural controllability. Our “effective augmentation” algorithm takes advantage of clusters intrinsic to the network topology, and permits rapidly and efficient augmentation of a large number of nodes in one time-step. “Effective augmentation” is shown to work successfully on a wide range of model and real networks. The method has numerous applications (e.g. study of biological, social, power and technological networks) and potentially of significant practical and economic value.

  12. Effective Augmentation of Complex Networks

    PubMed Central

    Wang, Jinjian; Yu, Xinghuo; Stone, Lewi

    2016-01-01

    Networks science plays an enormous role in many aspects of modern society from distributing electrical power across nations to spreading information and social networking amongst global populations. While modern networks constantly change in size, few studies have sought methods for the difficult task of optimising this growth. Here we study theoretical requirements for augmenting networks by adding source or sink nodes, without requiring additional driver-nodes to accommodate the change i.e., conserving structural controllability. Our “effective augmentation” algorithm takes advantage of clusters intrinsic to the network topology, and permits rapidly and efficient augmentation of a large number of nodes in one time-step. “Effective augmentation” is shown to work successfully on a wide range of model and real networks. The method has numerous applications (e.g. study of biological, social, power and technological networks) and potentially of significant practical and economic value. PMID:27165120

  13. Breast augmentation surgery

    MedlinePlus

    ... the shape of your breasts. Talk with a plastic surgeon if you are considering breast augmentation. Discuss ... mammograms or breast x-rays before surgery. The plastic surgeon will do a routine breast exam. Several ...

  14. Perceptually Augmented Simulator Design.

    PubMed

    Edmunds, T; Pai, D K

    2012-01-01

    Training simulators have proven their worth in a variety of fields, from piloting to air-traffic control to nuclear power station monitoring. Designing surgical simulators, however, poses the challenge of creating trainers that effectively instill not only high-level understanding of the steps to be taken in a given situation, but also the low-level "muscle-memory" needed to perform delicate surgical procedures. It is often impossible to build an ideal simulator that perfectly mimics the haptic experience of a surgical procedure, but by focussing on the aspects of the experience that are perceptually salient we can build simulators that effectively instill learning. We propose a general method for the design of surgical simulators that augment the perceptually salient aspects of an interaction. Using this method, we can increase skill-transfer rates without requiring expensive improvements in the capability of the rendering hardware or the computational complexity of the simulation. In this paper, we present our decomposition-based method for surgical simulator design, and describe a user-study comparing the training effectiveness of a haptic-search-task simulator designed using our method versus an unaugmented simulator. The results show that perception-based task decomposition can be used to improve the design of surgical simulators that effectively impart skill by targeting perceptually significant aspects of the interaction. PMID:26963831

  15. Effects of Performing Morning Versus Afternoon Exercise on Glycemic Control and Hypoglycemia Frequency in Type 1 Diabetes Patients on Sensor-Augmented Insulin Pump Therapy

    PubMed Central

    Gomez, Ana Maria; Gomez, Claudia; Aschner, Pablo; Veloza, Angelica; Muñoz, Oscar; Rubio, Claudia; Vallejo, Santiago

    2015-01-01

    Background: Although physical exercise (PE) is recommended for individuals with type 1 diabetes (DM1), participation in exercise is challenging because it increases the risk of severe hypoglycemia and the available therapeutic options to prevent it frequently result in hyperglycemia. There is no clear recommendation about the best timing for exercise. The aim of this study was to compare the risk of hypoglycemia after morning or afternoon exercise sessions up to 36 hours postworkout. Methods: This randomized crossover study enrolled subjects with DM1, older than 18 years of age, on sensor-augmented insulin pump (SAP) therapy. Participants underwent 2 moderate-intensity exercise sessions; 1 in the morning and 1 in the afternoon, separated by a 7 to 14 day wash-out period. Continuous glucose monitoring (CGM) data were collected 24 hours before, during and 36 hours after each session. Results: Thirty-five subjects (mean age 30.31 ± 12.66 years) participated in the study. The rate of hypoglycemia was significantly lower following morning versus afternoon exercise sessions (5.6 vs 10.7 events per patient, incidence rate ratio, 0.52; 95% CI, 0.43-0.63; P < .0001). Most hypoglycemic events occurred 15-24 hours after the session. On days following morning exercise sessions, there were 20% more CGM readings in near-euglycemic range (70-200 mg/dL) than on days prior to morning exercise (P = .003). Conclusions: Morning exercise confers a lower risk of late-onset hypoglycemia than afternoon exercise and improves metabolic control on the subsequent day. PMID:25555390

  16. Muzzle shunt augmentation of conventional railguns

    SciTech Connect

    Parker, J.V.

    1990-01-01

    Augmentation is a well-known technique for reducing the armature current and hence the armature power dissipation in a plasma armature railgun. In spite of the advantages, no large augmented railguns have been built, primarily due to the mechanical and electrical complexity introduce by the extra conductors required. It is possible to achieve some of the benefits of augmentation in conventional railgun by diverting a fraction {phi} of the input current through a shunt path at the muzzle of the railgun. In particular, the relation between force and armature current is the same as that obtained in an n-turn, series connected augmented railgun with n = 1/(1-{phi}). The price of this simplification is a reduction in electrical efficiency and some additional complexity in the external electrical system. Additions to the electrical system are required to establish the shunt current and to control its magnitude during projectile acceleration. The relationship between muzzle shunt augmentation and conventional series augmentation is developed and various techniques is developed and various techniques for establishing and controlling the shunt current are illustrated with a practical example. 5 refs., 8 figs., 2 tabs.

  17. Augmenting computer networks

    NASA Technical Reports Server (NTRS)

    Bokhari, S. H.; Raza, A. D.

    1984-01-01

    Three methods of augmenting computer networks by adding at most one link per processor are discussed: (1) A tree of N nodes may be augmented such that the resulting graph has diameter no greater than 4log sub 2((N+2)/3)-2. Thi O(N(3)) algorithm can be applied to any spanning tree of a connected graph to reduce the diameter of that graph to O(log N); (2) Given a binary tree T and a chain C of N nodes each, C may be augmented to produce C so that T is a subgraph of C. This algorithm is O(N) and may be used to produce augmented chains or rings that have diameter no greater than 2log sub 2((N+2)/3) and are planar; (3) Any rectangular two-dimensional 4 (8) nearest neighbor array of size N = 2(k) may be augmented so that it can emulate a single step shuffle-exchange network of size N/2 in 3(t) time steps.

  18. Ureteral bladder augmentation.

    PubMed

    Churchill, B M; Aliabadi, H; Landau, E H; McLorie, G A; Steckler, R E; McKenna, P H; Khoury, A E

    1993-08-01

    Virtually all segments of the gastrointestinal tract have been used successfully in augmentation cystoplasty. The complications inherent in enterocystoplasty are well described. Megaureters subtending effete kidneys (poorly or nonfunctioning) provide a novel and excellent source of augmentation material with urothelium and muscular backing, free of the electrolyte and acid base disturbances, and mucus production that plague enterocystoplasty. Augmentation cystoplasty using detubularized, reconfigured, otherwise disposable megaureter, with or without ipsilateral total or partial nephrectomy, was performed in 16 patients (mean age 8.8 years, range 1 to 25) with inadequate and dysfunctional bladders. Postoperative followup varied between 8 and 38 months (mean 22). The overall renal function and radiographic appearance of the remaining upper tracts have remained stable or improved in all patients. Of the 16 patients 15 require intermittent catheterization and 1 voids spontaneously. Ten patients are continent day and night, 5 have improved continence (4 damp at night and 1 stress incontinence) and 1 has failed to gain continence despite good capacity and compliance. Complete postoperative urodynamic evaluations in 12 of 13 patients show good capacity, low pressure bladders with no instability. Complications occurred in 5 patients, including transient urine extravasation in 2, contralateral ureterovesical obstruction in 2 and Mitrofanoff stomal stenosis in 1. Augmentation ureterocystoplasty combines the benefits common to all enterocystoplasties without adding any of the untoward complications or risks associated with nonurothelial augmentations. PMID:8326632

  19. Effect of xenograft (ABBM) particle size on vital bone formation following maxillary sinus augmentation: a multicenter, randomized, controlled, clinical histomorphometric trial.

    PubMed

    Testori, Tiziano; Wallace, Stephen S; Trisi, Paolo; Capelli, Matteo; Zuffetti, Francesco; Del Fabbro, Massimo

    2013-01-01

    The purpose of this study was a histomorphometric comparison of vital bone formation following maxillary sinus augmentation with two different particle sizes of anorganic bovine bone matrix (ABBM). Bilateral sinus floor augmentations were performed in 13 patients. Trephine bone cores were taken from the lateral window areas of 11 patients 6 to 8 months after augmentation for histologic and histomorphometric analysis. Bone samples from both the large and small particle size groups showed evidence of vital bone formation similar to that seen in previous studies, confirming the osteoconductivity of ABBM. Significant bone bridging was seen creating new trabeculae composed of the newly formed bone and residual ABBM particles. Histologic evaluation revealed the newly formed bone to be mostly woven bone with some remodeling to lamellar bone. Osteocytes were seen within the newly formed bone as well as osteoblast seams with recently formed osteoid. Isolated osteoclasts were observed on the ABBM surfaces. Vital bone formation (primary outcome measure) was more extensive in the large particle grafts compared with the small particle grafts (26.77% ± 9.63% vs 18.77% ± 4.74%, respectively). The histologic results reaffirm the osteoconductive ability of ABBM when used as the sole grafting material in maxillary sinus augmentation. The histomorphometric results at 6 to 8 months revealed a statistically significant increase (P = .02) in vital bone formation when the larger particle size was used. Additional studies should be performed to confirm these results. PMID:23820706

  20. Webizing mobile augmented reality content

    NASA Astrophysics Data System (ADS)

    Ahn, Sangchul; Ko, Heedong; Yoo, Byounghyun

    2014-01-01

    This paper presents a content structure for building mobile augmented reality (AR) applications in HTML5 to achieve a clean separation of the mobile AR content and the application logic for scaling as on the Web. We propose that the content structure contains the physical world as well as virtual assets for mobile AR applications as document object model (DOM) elements and that their behaviour and user interactions are controlled through DOM events by representing objects and places with a uniform resource identifier. Our content structure enables mobile AR applications to be seamlessly developed as normal HTML documents under the current Web eco-system.

  1. Efficacy and safety of oxytocin augmentation therapy for schizophrenia: an updated systematic review and meta-analysis of randomized, placebo-controlled trials.

    PubMed

    Oya, Kazuto; Matsuda, Yuki; Matsunaga, Shinji; Kishi, Taro; Iwata, Nakao

    2016-08-01

    The aim of this study was to perform a systematic review and an updated and comprehensive meta-analysis of oxytocin augmentation therapy in patients with schizophrenia who received antipsychotic agents. Data published up to 07/11/2015 were obtained from PubMed, PsycINFO, and Cochrane Library databases. We conducted a systematic review and meta-analysis of patients' data from randomized controlled trials (RCTs) comparing oxytocin with placebo. Relative risk (RR), standardized mean difference (SMD), and 95 % confidence intervals (95 % CI) based on the random-effects model were calculated. We included seven RCTs; the total sample size was 206 patients. Oxytocin was superior to placebo for decreasing the Positive and Negative Syndrome Scale (PANSS) general subscale scores (SMD = -0.44, 95 % CI -0.82 to -0.06, p = 0.02, I (2) = 0 %, N = 4, n = 112); however, it was not different from placebo for total symptoms (SMD = -0.46, 95 % CI -1.20 to 0.28, p = 0.22, I (2) = 80 %, N = 6, n = 162), positive symptoms (SMD = -0.18, 95 % CI -0.87 to 0.51, p = 0.60, I (2) = 81 %, N = 6, n = 192), and negative symptoms (SMD = -0.34, 95 % CI -0.76 to 0.08, p = 0.12, I (2) = 55 %, N = 7, n = 214). However, a sensitivity analysis including only oxytocin administration on consecutive days studies was superior to placebo in negative symptoms (SMD = -0.44, 95 % CI -0.87 to -0.01, p = 0.04, I (2) = 51 %, N = 6 n = 192). There were no significant differences for all-cause discontinuation (RR = 1.02) and individual side effects such as headache and dizziness between oxytocin and placebo. Oxytocin may improve PANSS general subscale scores in schizophrenia and seems to be well tolerated. However, because the number of studies in the current analysis was small, further study will be required using larger sample sizes. PMID:26303414

  2. Computer Augmented Lectures

    ERIC Educational Resources Information Center

    Seitz, W. A.; Matsen, F. A.

    1974-01-01

    Discusses the use of a central computer linked to a CRT console, with display projected onto a large screen, to operate computer augmentation of lectures in large group instruction. Indicates that both introductory tutorial and computer modes are feasible in subject matter presentation. (CC)

  3. Augmentative & Alternative Communication

    ERIC Educational Resources Information Center

    Murphy, Patti

    2007-01-01

    There is no definitive recipe for augmentative and alternative communication (AAC) success, but its universal ingredients can be found at home. The main ones are: (1) Understanding that all children need to express themselves, however outgoing or shy they may be; (2) Willingness to embrace the technology that may help your child regardless of your…

  4. Augmented Reality Binoculars.

    PubMed

    Oskiper, Taragay; Sizintsev, Mikhail; Branzoi, Vlad; Samarasekera, Supun; Kumar, Rakesh

    2015-05-01

    In this paper we present an augmented reality binocular system to allow long range high precision augmentation of live telescopic imagery with aerial and terrain based synthetic objects, vehicles, people and effects. The inserted objects must appear stable in the display and must not jitter and drift as the user pans around and examines the scene with the binoculars. The design of the system is based on using two different cameras with wide field of view and narrow field of view lenses enclosed in a binocular shaped shell. Using the wide field of view gives us context and enables us to recover the 3D location and orientation of the binoculars much more robustly, whereas the narrow field of view is used for the actual augmentation as well as to increase precision in tracking. We present our navigation algorithm that uses the two cameras in combination with an inertial measurement unit and global positioning system in an extended Kalman filter and provides jitter free, robust and real-time pose estimation for precise augmentation. We have demonstrated successful use of our system as part of information sharing example as well as a live simulated training system for observer training, in which fixed and rotary wing aircrafts, ground vehicles, and weapon effects are combined with real world scenes. PMID:26357208

  5. Stability-Augmentation Devices for Miniature Aircraft

    NASA Technical Reports Server (NTRS)

    Wood, RIchard M.

    2005-01-01

    Non-aerodynamic mechanical devices are under consideration as means to augment the stability of miniature autonomous and remotely controlled aircraft. Such aircraft can be used for diverse purposes, including military reconnaissance, radio communications, and safety-related monitoring of wide areas. The need for stability-augmentation devices arises because adverse meteorological conditions generally affect smaller aircraft more strongly than they affect larger aircraft: Miniature aircraft often become uncontrollable under conditions that would not be considered severe enough to warrant grounding of larger aircraft. The need for the stability-augmentation devices to be non-aerodynamic arises because there is no known way to create controlled aerodynamic forces sufficient to counteract the uncontrollable meteorological forces on miniature aircraft. A stability-augmentation device of the type under consideration includes a mass pod (a counterweight) at the outer end of a telescoping shaft, plus associated equipment to support the operation of the aircraft. The telescoping shaft and mass pod are stowed in the rear of the aircraft. When deployed, they extend below the aircraft. Optionally, an antenna for radio communication can be integrated into the shaft. At the time of writing this article, the deployment of the telescoping shaft and mass pod was characterized as passive and automatic, but information about the deployment mechanism(s) was not available. The feasibility of this stability-augmentation concept was demonstrated in flights of hand-launched prototype aircraft.

  6. Batten augmented triangular beam

    NASA Technical Reports Server (NTRS)

    Adams, Louis R.; Hedgepeth, John M.

    1986-01-01

    The BAT (Batten-Augmented Triangular) BEAM is characterized by battens which are buckled in the deployed state, thus preloading the truss. The preload distribution is determined, and the effects of various external loading conditions are investigated. The conceptual design of a deployer is described and loads are predicted. The influence of joint imperfections on effective member stiffness is investigated. The beam is assessed structurally.

  7. Postreduction Breast Augmentation

    PubMed Central

    Doft, Melissa A.

    2015-01-01

    Background: Most breast reduction patients are highly satisfied after surgery. However, there is a subset of women who seek breast augmentation years later to restore lost volume chiefly associated with weight loss and postpartum changes. Breast shape and overall aesthetics are often revised at the same time. Methods: A retrospective review was performed of 2 surgeons’ experiences with post-reduction breast augmentation. Twenty patients were identified between 2002 and 2014. An in-depth chart review was conducted to determine patient motivation and to examine the operative techniques employed. Implant variables, a reduction specimen weight to implant volume comparison (where available), and complications are reported. Results: The average age was 37.1 years and average body mass index was 21.8 kg/m2. Most patients waited over a decade to have their breasts revised. Weight loss was the motivating factor in 8 patients and pregnancy changes in 11. Nineteen patients wished to stay with the same bra size or 1 cup size larger. Although all patients elected to have an implant placed, 19 patients wished to have an improved breast shape, not specifically a larger volume. The average breast implant was 203.5 cm3 (range, 120–340 cm3). Complications from implant placement included a seroma treated by aspiration and a Baker class III capsular contracture that required surgical correction. Conclusions: A small subset of reduction mammaplasty patients seek breast augmentation many years later primarily to improve breast contour, not to restore their prereduction breast volumes. Conservative augmentation combined with revision of breast shape and areolar aesthetics yields good results with minimal complications. PMID:26579333

  8. Specific Phobias in Youth: A Randomized Controlled Trial Comparing One-Session Treatment to a Parent-Augmented One-Session Treatment

    PubMed Central

    Ollendick, Thomas H.; Halldorsdottir, Thorhildur; Fraire, Maria G; Austin, Kristin E.; Noguchi, Ryoichi J. P.; Lewis, Krystal M.; Jarrett, Matthew A.; Cunningham, Natoshia R.; Canavera, Kristin; Allen, Kristy B.; Whitmore, Maria J.

    2015-01-01

    Objective Examine the efficacy of a parent-augmented One Session Treatment (A-OST) in treating specific phobias (SP) in youth by comparing this novel treatment to child-focused OST, a well-established treatment. Method A total of 97 youth (ages 6–15, 51.5% female, 84.5% white) who fulfilled diagnostic criteria for SP were randomized to either A-OST or OST. SPs were assessed with semi-structured diagnostic interviews, clinician improvement ratings, and parent and child improvement ratings. In addition, measures of treatment satisfaction and parental self-efficacy were obtained. Blind assessments were completed pretreatment, post-treatment, and 1-month and 6-months following treatment. Analyses were undertaken using mixed models. In addition, gender, age, internalizing/externalizing problems, parent overprotection, and parent anxiety were examined as potential predictors and moderators of treatment outcome. Results Both treatment conditions produced similar outcomes with approximately 50% of youth in both treatments diagnosis free and judged to be much or very much improved at post-treatment and 1-month follow up. At 6-month follow up, however, the treatments diverged with OST resulting in marginally superior outcomes to A-OST, contrary to predictions. Only age of child predicted treatment outcome across the two treatments (older children did better); unexpectedly, none of the variables moderated treatment outcomes. Conclusions Parent augmentation of OST produced no appreciable gains in treatment outcomes. Directions for future research are highlighted. PMID:25645164

  9. Neurally augmented sexual function.

    PubMed

    Meloy, S

    2007-01-01

    Neurally Augmented Sexual Function (NASF) is a technique utilizing epidural electrodes to restore and improve sexual function. Orgasmic dysfunction is common in adult women, affecting roughly one quarter of populations studied. Many male patients suffering from erectile dysfunction are not candidates for phosphdiesterase therapy due to concomitant nitrate therapy. Positioning the electrodes at roughly the level of the cauda equina allows for stimulation of somatic efferents and afferents as well as modifying sympathetic and parasympathetic activity. Our series of women treated by NASF is described. Our experience shows that the evaluation of potential candidates for both correctable causes and psychological screening are important considerations. PMID:17691397

  10. History of gluteal augmentation.

    PubMed

    de la Peña, J Abel; Rubio, Omar V; Cano, Jacobo P; Cedillo, Mariana C; Garcés, Miriam T

    2006-07-01

    The concept of female beauty has changed throughout time, but the form and size of the breasts and gluteal region have remained constant as symbols of maximum femininity. Sculptures and prints show us feminine figures that are voluminous and reflect human history's interest in fertility. The early years of gluteal augmentation saw few published reports that described the procedure technique, follow-up, or possible complications. But developments continued as surgeons began experimenting with different anatomical planes for implant placement. The most important goal in plastic surgery is meeting a patient's expectations. It is important for the surgeon to thoroughly explain to patients what can realistically be achieved with a procedure. PMID:16818090

  11. Folate augmentation of antidepressant response.

    PubMed

    Owen, R T

    2013-12-01

    The use of two antidepressants from the initiation of treatment in major depressive disorder has been investigated in several recent studies and forms a paradigm shift in the pharmacotherapy of the condition. Several, but not all, trials have claimed improved response and remission rates with the combinations as opposed to monotherapy. The use of folate preparations (folic and folinic acid and l-meth-ylfolate) have shown effective augmentation of antidepressant response in a variety of controlled and open-label settings in patients with normo- and hypofolatemic status. Several recent trials using L-methylfolate, the active and more bioavailable form of folic acid, have shown promising adjunctive use with a well-tolerated adverse event profile. PMID:24524097

  12. Six-Month Follow-Up of a Randomized Controlled Trial Augmenting Serotonin Reuptake Inhibitor Treatment With Exposure and Ritual Prevention for Obsessive-Compulsive Disorder

    PubMed Central

    Foa, Edna B.; Simpson, Helen Blair; Liebowitz, Michael R.; Powers, Mark B.; Rosenfield, David; Cahill, Shawn P.; Campeas, Raphael; Franklin, Martin; Hahn, Chang-Gyu; Hembree, Elizabeth A.; Huppert, Jonathan D.; Schmidt, Andrew B.; Vermes, Donna; Williams, Monnica T.

    2014-01-01

    Objective This article describes the long-term effects of augmenting serotonin reuptake inhibitors (SRIs) with exposure and ritual prevention or stress management training in patients with DSM-IV obsessive-compulsive disorder (OCD). Method Between November 2000 and November 2006, 111 OCD patients from 2 academic outpatient centers with partial SRI response were randomized to the addition of exposure and ritual prevention or stress management training, delivered twice weekly for 8 weeks (acute phase); 108 began treatment. Responders (38 of 52 in the exposure and ritual prevention condition, 11 of 52 in the stress management training condition) entered a 24-week maintenance phase. The Yale-Brown Obsessive Compulsive Scale (YBOCS) was the primary outcome measure. Results After 24 weeks, patients randomized to and receiving exposure and ritual prevention versus stress management training had significantly better outcomes (mean YBOCS scores of 14.69 and 21.37, respectively; t = 2.88, P = .005), higher response rates (decrease in YBOCS scores ≥ 25%: 40.7% vs 9.3%, Fisher exact test P < .001), and higher rates of excellent response (YBOCS score ≤ 12: 24.1% vs 5.6%, Fisher exact test P = .01). During the maintenance phase, the slope of change in YBOCS scores was not significant in either condition (all P values ≥ .55), with no difference between exposure and ritual prevention and stress management training (P > .74). Better outcome was associated with baseline variables: lower YBOCS scores, higher quality of life, fewer comorbid Axis I diagnoses, and male sex. Conclusions Augmenting SRIs with exposure and ritual prevention versus stress management training leads to better outcome after acute treatment and 24 weeks later. Maintenance outcome, however, was primarily a function of OCD severity at entrance. Greater improvement during the acute phase influences how well patients maintain their gains, regardless of treatment condition. PMID:23759449

  13. Wireless Augmented Reality Prototype (WARP)

    NASA Technical Reports Server (NTRS)

    Devereaux, A. S.

    1999-01-01

    Initiated in January, 1997, under NASA's Office of Life and Microgravity Sciences and Applications, the Wireless Augmented Reality Prototype (WARP) is a means to leverage recent advances in communications, displays, imaging sensors, biosensors, voice recognition and microelectronics to develop a hands-free, tetherless system capable of real-time personal display and control of computer system resources. Using WARP, an astronaut may efficiently operate and monitor any computer-controllable activity inside or outside the vehicle or station. The WARP concept is a lightweight, unobtrusive heads-up display with a wireless wearable control unit. Connectivity to the external system is achieved through a high-rate radio link from the WARP personal unit to a base station unit installed into any system PC. The radio link has been specially engineered to operate within the high- interference, high-multipath environment of a space shuttle or space station module. Through this virtual terminal, the astronaut will be able to view and manipulate imagery, text or video, using voice commands to control the terminal operations. WARP's hands-free access to computer-based instruction texts, diagrams and checklists replaces juggling manuals and clipboards, and tetherless computer system access allows free motion throughout a cabin while monitoring and operating equipment.

  14. Creating Tangible Interfaces by Augmenting Physical Objects with Multimodal Language

    SciTech Connect

    McGee, David R. ); Cohen, Philip R.

    2001-01-01

    Rasa is a tangible augmented reality environment that digitally enhances the existing paper-based command and control capability in a military command post. By observing and understanding the users' speech, pen, and touch-based multimodal language, Rasa computationally augments the physical objects on a command post map, linking these items to digital representations of the same; for example, linking a paper map to the world and Post-it notes to military units. Herein, we give a thorough account of Rasa's underlying multiagent framework, and its recognition, understanding, and multimodal integration components. Moreover, we examine five properties of language: generativity, comprehensibility, compositionality, referentiality, and, at times, persistence--that render it suitable as an augmentation approach, contrasting these properties to those of other augmentation methods. It is these properties of language that allow users of Rasa to augment physical objects, transforming them into tangible interfaces.

  15. Augmented Virtual Reality Laboratory

    NASA Technical Reports Server (NTRS)

    Tully-Hanson, Benjamin

    2015-01-01

    Real time motion tracking hardware has for the most part been cost prohibitive for research to regularly take place until recently. With the release of the Microsoft Kinect in November 2010, researchers now have access to a device that for a few hundred dollars is capable of providing redgreenblue (RGB), depth, and skeleton data. It is also capable of tracking multiple people in real time. For its original intended purposes, i.e. gaming, being used with the Xbox 360 and eventually Xbox One, it performs quite well. However, researchers soon found that although the sensor is versatile, it has limitations in real world applications. I was brought aboard this summer by William Little in the Augmented Virtual Reality (AVR) Lab at Kennedy Space Center to find solutions to these limitations.

  16. NASA Communications Augmentation network

    NASA Technical Reports Server (NTRS)

    Omidyar, Guy C.; Butler, Thomas E.; Laios, Straton C.

    1990-01-01

    The NASA Communications (Nascom) Division of the Mission Operations and Data Systems Directorate (MO&DSD) is to undertake a major initiative to develop the Nascom Augmentation (NAUG) network to achieve its long-range service objectives for operational data transport to support the Space Station Freedom Program, the Earth Observing System (EOS), and other projects. The NAUG is the Nascom ground communications network being developed to accommodate the operational traffic of the mid-1990s and beyond. The NAUG network development will be based on the Open Systems Interconnection Reference Model (OSI-RM). This paper describes the NAUG network architecture, subsystems, topology, and services; addresses issues of internetworking the Nascom network with other elements of the Space Station Information System (SSIS); discusses the operations environment. This paper also notes the areas of related research and presents the current conception of how the network will provide broadband services in 1998.

  17. NASA Communications Augmentation network

    NASA Astrophysics Data System (ADS)

    Omidyar, Guy C.; Butler, Thomas E.; Laios, Straton C.

    1990-09-01

    The NASA Communications (Nascom) Division of the Mission Operations and Data Systems Directorate (MO&DSD) is to undertake a major initiative to develop the Nascom Augmentation (NAUG) network to achieve its long-range service objectives for operational data transport to support the Space Station Freedom Program, the Earth Observing System (EOS), and other projects. The NAUG is the Nascom ground communications network being developed to accommodate the operational traffic of the mid-1990s and beyond. The NAUG network development will be based on the Open Systems Interconnection Reference Model (OSI-RM). This paper describes the NAUG network architecture, subsystems, topology, and services; addresses issues of internetworking the Nascom network with other elements of the Space Station Information System (SSIS); discusses the operations environment. This paper also notes the areas of related research and presents the current conception of how the network will provide broadband services in 1998.

  18. Magnetohydrodynamic Augmented Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.

    2008-01-01

    Over the past several years, efforts have been under way to design and develop an operationally flexible research facility for investigating the use of cross-field MHD accelerators as a potential thrust augmentation device for thermal propulsion systems. The baseline configuration for this high-power experimental facility utilizes a 1.5-MWe multi-gas arc-heater as a thermal driver for a 2-MWe MHD accelerator, which resides in a large-bore 2-tesla electromagnet. A preliminary design study using NaK seeded nitrogen as the working fluid led to an externally diagonalized segmented MHD channel configuration based on an expendable heat-sink design concept. The current status report includes a review of engineering/design work and performance optimization analyses and summarizes component hardware fabrication and development efforts, preliminary testing results, and recent progress toward full-up assembly and testing

  19. NAESA Augmentation Pilot Project

    NASA Technical Reports Server (NTRS)

    Hoover, John J.

    1998-01-01

    This project was one project within the Native American Earth and Space Academy (NAESA). NAESA is a national initiative comprised of several organizations that support programs which focus on 1) enhancing the technological, scientific and pedagogical skills of K-14 teachers who instruct Native Americans, 2) enhancing the understanding and applications of science, technology, and engineering of college-bound Native Americans and teaching them general college "survival skills" (e.g., test taking, time management, study habits), 3) enhancing the scientific and pedagogical skills of the faculty of tribally-controllcd colleges and community colleges with large Native American enrollments, and 4) strengthening the critical relationships between students, their parents, tribal elders, and their communities. This Augmentation Pilot Project focused on the areas of community-school alliances and intemet technology use in teaching and learning and daily living addressing five major objectives.

  20. Augmented Reality Comes to Physics

    ERIC Educational Resources Information Center

    Buesing, Mark; Cook, Michael

    2013-01-01

    Augmented reality (AR) is a technology used on computing devices where processor-generated graphics are rendered over real objects to enhance the sensory experience in real time. In other words, what you are really seeing is augmented by the computer. Many AR games already exist for systems such as Kinect and Nintendo 3DS and mobile apps, such as…

  1. B-52 stability augmentation system reliability

    NASA Technical Reports Server (NTRS)

    Bowling, T. C.; Key, L. W.

    1976-01-01

    The B-52 SAS (Stability Augmentation System) was developed and retrofitted to nearly 300 aircraft. It actively controls B-52 structural bending, provides improved yaw and pitch damping through sensors and electronic control channels, and puts complete reliance on hydraulic control power for rudder and elevators. The system has experienced over 300,000 flight hours and has exhibited service reliability comparable to the results of the reliability test program. Development experience points out numerous lessons with potential application in the mechanization and development of advanced technology control systems of high reliability.

  2. Infusing CD19-Directed T Cells to Augment Disease Control in Patients Undergoing Autologous Hematopoietic Stem-Cell Transplantation for Advanced B-Lymphoid Malignancies

    PubMed Central

    Kebriaei, Partow; Huls, Helen; Jena, Bipulendu; Munsell, Mark; Jackson, Rineka; Lee, Dean A.; Hackett, Perry B.; Rondon, Gabriela; Shpall, Elizabeth; Champlin, Richard E.

    2012-01-01

    Abstract Limited curative treatment options exist for patients with advanced B-lymphoid malignancies, and new therapeutic approaches are needed to augment the efficacy of hematopoietic stem-cell transplantation (HSCT). Cellular therapies, such as adoptive transfer of T cells that are being evaluated to target malignant disease, use mechanisms independent of chemo- and radiotherapy with nonoverlapping toxicities. Gene therapy is employed to generate tumor-specific T cells, as specificity can be redirected through enforced expression of a chimeric antigen receptor (CAR) to achieve antigen recognition based on the specificity of a monoclonal antibody. By combining cell and gene therapies, we have opened a new Phase I protocol at the MD Anderson Cancer Center (Houston, TX) to examine the safety and feasibility of administering autologous genetically modified T cells expressing a CD19-specific CAR (capable of signaling through chimeric CD28 and CD3-ζ) into patients with high-risk B-lymphoid malignancies undergoing autologous HSCT. The T cells are genetically modified by nonviral gene transfer of the Sleeping Beauty system and CAR+ T cells selectively propagated in a CAR-dependent manner on designer artificial antigen-presenting cells. The results of this study will lay the foundation for future protocols including CAR+ T-cell infusions derived from allogeneic sources. PMID:22107246

  3. An Augmentation of G-Guidance Algorithms

    NASA Technical Reports Server (NTRS)

    Carson, John M. III; Acikmese, Behcet

    2011-01-01

    The original G-Guidance algorithm provided an autonomous guidance and control policy for small-body proximity operations that took into account uncertainty and dynamics disturbances. However, there was a lack of robustness in regards to object proximity while in autonomous mode. The modified GGuidance algorithm was augmented with a second operational mode that allows switching into a safety hover mode. This will cause a spacecraft to hover in place until a mission-planning algorithm can compute a safe new trajectory. No state or control constraints are violated. When a new, feasible state trajectory is calculated, the spacecraft will return to standard mode and maneuver toward the target. The main goal of this augmentation is to protect the spacecraft in the event that a landing surface or obstacle is closer or further than anticipated. The algorithm can be used for the mitigation of any unexpected trajectory or state changes that occur during standard mode operations

  4. Magnetohydrodynamic Augmented Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.; Cole, John; Lineberry, John; Chapman, Jim; Schmidt, Harold; Cook, Stephen (Technical Monitor)

    2002-01-01

    A fundamental obstacle to routine space access is the specific energy limitations associated with chemical fuels. In the case of vertical take-off, the high thrust needed for vertical liftoff and acceleration to orbit translates into power levels in the 10 GW range. Furthermore, useful payload mass fractions are possible only if the exhaust particle energy (i.e., exhaust velocity) is much greater than that available with traditional chemical propulsion. The electronic binding energy released by the best chemical reactions (e.g., LOX/LH2 for example, is less than 2 eV per product molecule (approx. 1.8 eV per H2O molecule), which translates into particle velocities less than 5 km/s. Useful payload fractions, however, will require exhaust velocities exceeding 15 km/s (i.e., particle energies greater than 20 eV). As an added challenge, the envisioned hypothetical RLV (reusable launch vehicle) should accomplish these amazing performance feats while providing relatively low acceleration levels to orbit (2-3g maximum). From such fundamental considerations, it is painfully obvious that planned and current RLV solutions based on chemical fuels alone represent only a temporary solution and can only result in minor gains, at best. What is truly needed is a revolutionary approach that will dramatically reduce the amount of fuel and size of the launch vehicle. This implies the need for new compact high-power energy sources as well as advanced accelerator technologies for increasing engine exhaust velocity. Electromagnetic acceleration techniques are of immense interest since they can be used to circumvent the thermal limits associated with conventional propulsion systems. This paper describes the Magnetohydrodynamic Augmented Propulsion Experiment (MAPX) being undertaken at NASA Marshall Space Flight Center (MSFC). In this experiment, a 1-MW arc heater is being used as a feeder for a 1-MW magnetohydrodynamic (MHD) accelerator. The purpose of the experiment is to demonstrate

  5. Treatment of phantom limb pain (PLP) based on augmented reality and gaming controlled by myoelectric pattern recognition: a case study of a chronic PLP patient.

    PubMed

    Ortiz-Catalan, Max; Sander, Nichlas; Kristoffersen, Morten B; Håkansson, Bo; Brånemark, Rickard

    2014-01-01

    A variety of treatments have been historically used to alleviate phantom limb pain (PLP) with varying efficacy. Recently, virtual reality (VR) has been employed as a more sophisticated mirror therapy. Despite the advantages of VR over a conventional mirror, this approach has retained the use of the contralateral limb and is therefore restricted to unilateral amputees. Moreover, this strategy disregards the actual effort made by the patient to produce phantom motions. In this work, we investigate a treatment in which the virtual limb responds directly to myoelectric activity at the stump, while the illusion of a restored limb is enhanced through augmented reality (AR). Further, phantom motions are facilitated and encouraged through gaming. The proposed set of technologies was administered to a chronic PLP patient who has shown resistance to a variety of treatments (including mirror therapy) for 48 years. Individual and simultaneous phantom movements were predicted using myoelectric pattern recognition and were then used as input for VR and AR environments, as well as for a racing game. The sustained level of pain reported by the patient was gradually reduced to complete pain-free periods. The phantom posture initially reported as a strongly closed fist was gradually relaxed, interestingly resembling the neutral posture displayed by the virtual limb. The patient acquired the ability to freely move his phantom limb, and a telescopic effect was observed where the position of the phantom hand was restored to the anatomically correct distance. More importantly, the effect of the interventions was positively and noticeably perceived by the patient and his relatives. Despite the limitation of a single case study, the successful results of the proposed system in a patient for whom other medical and non-medical treatments have been ineffective justifies and motivates further investigation in a wider study. PMID:24616655

  6. Treatment of phantom limb pain (PLP) based on augmented reality and gaming controlled by myoelectric pattern recognition: a case study of a chronic PLP patient

    PubMed Central

    Ortiz-Catalan, Max; Sander, Nichlas; Kristoffersen, Morten B.; Håkansson, Bo; Brånemark, Rickard

    2014-01-01

    A variety of treatments have been historically used to alleviate phantom limb pain (PLP) with varying efficacy. Recently, virtual reality (VR) has been employed as a more sophisticated mirror therapy. Despite the advantages of VR over a conventional mirror, this approach has retained the use of the contralateral limb and is therefore restricted to unilateral amputees. Moreover, this strategy disregards the actual effort made by the patient to produce phantom motions. In this work, we investigate a treatment in which the virtual limb responds directly to myoelectric activity at the stump, while the illusion of a restored limb is enhanced through augmented reality (AR). Further, phantom motions are facilitated and encouraged through gaming. The proposed set of technologies was administered to a chronic PLP patient who has shown resistance to a variety of treatments (including mirror therapy) for 48 years. Individual and simultaneous phantom movements were predicted using myoelectric pattern recognition and were then used as input for VR and AR environments, as well as for a racing game. The sustained level of pain reported by the patient was gradually reduced to complete pain-free periods. The phantom posture initially reported as a strongly closed fist was gradually relaxed, interestingly resembling the neutral posture displayed by the virtual limb. The patient acquired the ability to freely move his phantom limb, and a telescopic effect was observed where the position of the phantom hand was restored to the anatomically correct distance. More importantly, the effect of the interventions was positively and noticeably perceived by the patient and his relatives. Despite the limitation of a single case study, the successful results of the proposed system in a patient for whom other medical and non-medical treatments have been ineffective justifies and motivates further investigation in a wider study. PMID:24616655

  7. Augmented Likelihood Image Reconstruction.

    PubMed

    Stille, Maik; Kleine, Matthias; Hägele, Julian; Barkhausen, Jörg; Buzug, Thorsten M

    2016-01-01

    The presence of high-density objects remains an open problem in medical CT imaging. Data of projections passing through objects of high density, such as metal implants, are dominated by noise and are highly affected by beam hardening and scatter. Reconstructed images become less diagnostically conclusive because of pronounced artifacts that manifest as dark and bright streaks. A new reconstruction algorithm is proposed with the aim to reduce these artifacts by incorporating information about shape and known attenuation coefficients of a metal implant. Image reconstruction is considered as a variational optimization problem. The afore-mentioned prior knowledge is introduced in terms of equality constraints. An augmented Lagrangian approach is adapted in order to minimize the associated log-likelihood function for transmission CT. During iterations, temporally appearing artifacts are reduced with a bilateral filter and new projection values are calculated, which are used later on for the reconstruction. A detailed evaluation in cooperation with radiologists is performed on software and hardware phantoms, as well as on clinically relevant patient data of subjects with various metal implants. Results show that the proposed reconstruction algorithm is able to outperform contemporary metal artifact reduction methods such as normalized metal artifact reduction. PMID:26208310

  8. Structural consequences of railgun augmentation

    SciTech Connect

    Wellman, G.W.; Schuler, K.W. . Applied Mechanics Div. III)

    1989-01-01

    An augmented railgun can provide the same driving force on a projectile at a lower plasma arc current and thus less potential erosion and barrel damage as an unaugmented railgun. However, there are structural consequences to railgun augmentation which must be overcome before the advantages of lower plasma arc currents can be realized. To investigate these consequences, a bolted V-block supporting structure is considered with two cores; unaugmented (a single pair of conducting rails), and augmented (conducting rails augmented by a second tandem set of conductors). The mechanical load on the cores consist of the static bolt preload, the plasma pressure behind the projectile, and the magnetic pressure induced by currents flowing in the rails or augmenting conductors. Assuming no current diffusion into the conductors, the magnetic pressure distribution on the conductors is determined by solving the two dimensional magnetostatic field equations using an analogy with heat transfer. These loads are then used in a dynamic finite element structural model. The maximum rail current is found at which the unaugmented railgun can be repetitively fired without detrimental gaps forming at the bore. For the augmented railgun, at the same projectile acceleration, large permanent deformations can occur. Thus successful implementation of rail gun augmentation will require improvement of the supporting structure.

  9. Structural consequences of railgun augmentation

    SciTech Connect

    Wellman, G.W.; Schuler, K.W.

    1988-01-01

    An augmented railgun can provide the same driving force on a projectile at a lower plasma arc current and thus less potential erosion and barrel damage as an unaugmented railgun. However, there are structural consequences to railgun augmentation which must be overcome before the advantages of lower plasma arc currents can be realized. To investigate these consequences, a bolted V-block supporting structure is considered with two cores; unaugmented (a single pair of conducting rails), and augmented (conducting rails augmented by a second tandem set of conductors). The mechanical load on the cores consist of the static bolt preload, the plasma pressure behind the projectile, and the magnetic pressure induced by currents flowing in the rails or augmenting conductors. Assuming no current diffusion into the conductors, the magnetic pressure distribution on the conductors is determined by solving the two-dimensional magnetostatic field equations using an analogy with heat transfer. These loads are then used in a dynamic finite element structural model. The maximum rail current is found at which the unaugmented railgun can be repetitively fired without detrimental gaps forming at the bore. For the augmented railgun, at the same projectile acceleration, large permanent deformations can occur. Thus successful implementation of rail gun augmentation will require improvement of the supporting structure.

  10. Augmented Reality Comes to Physics

    NASA Astrophysics Data System (ADS)

    Buesing, Mark; Cook, Michael

    2013-04-01

    Augmented reality (AR) is a technology used on computing devices where processor-generated graphics are rendered over real objects to enhance the sensory experience in real time. In other words, what you are really seeing is augmented by the computer. Many AR games already exist for systems such as Kinect and Nintendo 3DS and mobile apps, such as Tagwhat and Star Chart (a must for astronomy class). The yellow line marking first downs in a televised football game2 and the enhanced puck that makes televised hockey easier to follow3 both use augmented reality to do the job.

  11. Mersiline mesh in premaxillary augmentation.

    PubMed

    Foda, Hossam M T

    2005-01-01

    Premaxillary retrusion may distort the aesthetic appearance of the columella, lip, and nasal tip. This defect is characteristically seen in, but not limited to, patients with cleft lip nasal deformity. This study investigated 60 patients presenting with premaxillary deficiencies in which Mersiline mesh was used to augment the premaxilla. All the cases had surgery using the external rhinoplasty technique. Two methods of augmentation with Mersiline mesh were used: the Mersiline roll technique, for the cases with central symmetric deficiencies, and the Mersiline packing technique, for the cases with asymmetric deficiencies. Premaxillary augmentation with Mersiline mesh proved to be simple technically, easy to perform, and not associated with any complications. Periodic follow-up evaluation for a mean period of 32 months (range, 12-98 months) showed that an adequate degree of premaxillary augmentation was maintained with no clinically detectable resorption of the mesh implant. PMID:15959688

  12. Augmented reality for wafer prober

    NASA Astrophysics Data System (ADS)

    Gilgenkrantz, Pascal

    2011-03-01

    The link between wafer manufacturing and wafer test is often weak: without common information system, Test engineers have to read locations of test structures from reference documents and search them on the wafer prober screen. Mask Data Preparation team is ideally placed to fill this gap, given its relationship with both design and manufacturing sides. With appropriate design extraction scripts and design conventions, mask engineers can provide exact wafer locations of all embedded test structures to avoid a painful camera search. Going a step further, it would be a great help to provide to wafer probers a "map" of what was build on wafers. With this idea in mind, mask design database can simply be provided to Test engineers; but the real added value would come from a true integration of real-wafer camera views and design database used for wafer manufacturing. As proven by several augmented reality applications, like Google Maps' mixed Satellite/Map view, mixing a real-world view with its theoretical model is very useful to understand the reality. The creation of such interface can only be made by a wafer prober manufacturer, given the high integration of these machines with their control panel. But many existing software libraries could be used to plot the design view matching the camera view. Standard formats for mask design are usually GDSII and OASIS (SEMI P39 standard); multiple free software and commercial viewers/editors/libraries for these formats are available.

  13. Design and numerical evaluation of full-authority flight control systems for conventional and thruster-augmented helicopters employed in NOE operations

    NASA Technical Reports Server (NTRS)

    Perri, Todd A.; Mckillip, R. M., Jr.; Curtiss, H. C., Jr.

    1987-01-01

    The development and methodology is presented for development of full-authority implicit model-following and explicit model-following optimal controllers for use on helicopters operating in the Nap-of-the Earth (NOE) environment. Pole placement, input-output frequency response, and step input response were used to evaluate handling qualities performance. The pilot was equipped with velocity-command inputs. A mathematical/computational trajectory optimization method was employed to evaluate the ability of each controller to fly NOE maneuvers. The method determines the optimal swashplate and thruster input histories from the helicopter's dynamics and the prescribed geometry and desired flying qualities of the maneuver. Three maneuvers were investigated for both the implicit and explicit controllers with and without auxiliary propulsion installed: pop-up/dash/descent, bob-up at 40 knots, and glideslope. The explicit controller proved to be superior to the implicit controller in performance and ease of design.

  14. Orion MPCV Continuum RCS Heating Augmentation Model Development

    NASA Technical Reports Server (NTRS)

    Hyatt, Andrew J.; White, Molly E.

    2014-01-01

    The reaction control system jets of the Orion Multi Purpose Crew Vehicle can have a significant impact on the magnitude and distribution of the surface heat flux on the leeside of the aft-body, when they are fired. Changes in surface heating are expressed in terms of augmentation factor over the baseline smooth body heating. Wind tunnel tests revealed heating augmentation factors as high as 13.0, 7.6, 2.8, and 5.8 for the roll, pitch down, pitch up, and yaw jets respectively. Heating augmentation factor models, based almost exclusively on data from a series of wind tunnel tests have been developed, for the purposes of thermal protection system design. The wind tunnel tests investigated several potential jet-to-freestream similarity parameters, and heating augmentation factors derived from the data showed correlation with the jet-to-freestream momentum ratio. However, this correlation was not utilized in the developed models. Instead augmentation factors were held constant throughout the potential trajectory space. This simplification was driven by the fact that ground to flight traceability and sting effects are not well understood. Given the sensitivity of the reaction control system jet heating augmentation to configuration, geometry, and orientation the focus in the present paper is on the methodology used to develop the models and the lessons learned from the data. The models that are outlined in the present work are specific to the aerothermal database used to design the thermal protection system for the Exploration Flight Test 1 vehicle.

  15. Augmenting ejector endwall effects. [V/STOL aircraft

    NASA Technical Reports Server (NTRS)

    Porter, J. L.; Squyers, R. A.

    1979-01-01

    Rectangular inlet ejectors which had multiple hypermixing nozzles for their primary jets were investigated for the effects of endwall blowing on thrust augmentation performance. The ejector configurations tested had both straight wall and active boundary layer control type diffusers. Endwall flows were energized and controlled by simple blowing jets suitably located in the ejector. Both the endwall and boundary layer control diffuser blowing rates were varied to determine optimum performance. High area ratio diffusers with insufficient endwall blowing showed endwall separation and rapid degradation of thrust performance. Optimized values of diffuser boundary layer control and endwall nozzle blowing rates in an ejector augmenter were shown to achieve high levels of augmentation performance for maximum compactness.

  16. Cortical Modulation of Motor Control Biofeedback among the Elderly with High Fall Risk during a Posture Perturbation Task with Augmented Reality.

    PubMed

    Chang, Chun-Ju; Yang, Tsui-Fen; Yang, Sai-Wei; Chern, Jen-Suh

    2016-01-01

    The cerebral cortex provides sensorimotor integration and coordination during motor control of daily functional activities. Power spectrum density based on electroencephalography (EEG) has been employed as an approach that allows an investigation of the spatial-temporal characteristics of neuromuscular modulation; however, the biofeedback mechanism associated with cortical activation during motor control remains unclear among elderly individuals. Thirty one community-dwelling elderly participants were divided into low fall-risk potential (LF) and high fall-risk potential (HF) groups based upon the results obtained from a receiver operating characteristic analysis of the ellipse area of the center of pressure. Electroencephalography (EEG) was performed while the participants stood on a 6-degree-of-freedom Stewart platform, which generated continuous perturbations and done either with or without the virtual reality scene. The present study showed that when there was visual stimulation and poor somatosensory coordination, a higher level of cortical response was activated in order to keep postural balance. The elderly participants in the LF group demonstrated a significant and strong correlation between postural-related cortical regions; however, the elderly individuals in the HF group did not show such a relationship. Moreover, we were able to clarify the roles of various brainwave bands functioning in motor control. Specifically, the gamma and beta bands in the parietal-occipital region facilitate the high-level cortical modulation and sensorimotor integration, whereas the theta band in the frontal-central region is responsible for mediating error detection during perceptual motor tasks. Finally, the alpha band is associated with processing visual challenges in the occipital lobe.With a variety of motor control demands, increment in brainwave band coordination is required to maintain postural stability. These investigations shed light on the cortical modulation of

  17. Cortical Modulation of Motor Control Biofeedback among the Elderly with High Fall Risk during a Posture Perturbation Task with Augmented Reality

    PubMed Central

    Chang, Chun-Ju; Yang, Tsui-Fen; Yang, Sai-Wei; Chern, Jen-Suh

    2016-01-01

    The cerebral cortex provides sensorimotor integration and coordination during motor control of daily functional activities. Power spectrum density based on electroencephalography (EEG) has been employed as an approach that allows an investigation of the spatial–temporal characteristics of neuromuscular modulation; however, the biofeedback mechanism associated with cortical activation during motor control remains unclear among elderly individuals. Thirty one community-dwelling elderly participants were divided into low fall-risk potential (LF) and high fall-risk potential (HF) groups based upon the results obtained from a receiver operating characteristic analysis of the ellipse area of the center of pressure. Electroencephalography (EEG) was performed while the participants stood on a 6-degree-of-freedom Stewart platform, which generated continuous perturbations and done either with or without the virtual reality scene. The present study showed that when there was visual stimulation and poor somatosensory coordination, a higher level of cortical response was activated in order to keep postural balance. The elderly participants in the LF group demonstrated a significant and strong correlation between postural-related cortical regions; however, the elderly individuals in the HF group did not show such a relationship. Moreover, we were able to clarify the roles of various brainwave bands functioning in motor control. Specifically, the gamma and beta bands in the parietal–occipital region facilitate the high-level cortical modulation and sensorimotor integration, whereas the theta band in the frontal–central region is responsible for mediating error detection during perceptual motor tasks. Finally, the alpha band is associated with processing visual challenges in the occipital lobe.With a variety of motor control demands, increment in brainwave band coordination is required to maintain postural stability. These investigations shed light on the cortical modulation

  18. Augmentation cystoplasty in neurogenic bladder.

    PubMed

    Çetinel, Bülent; Kocjancic, Ervin; Demirdağ, Çetin

    2016-09-01

    The aim of this review is to update the indications, contraindications, technique, complications, and the tissue engineering approaches of augmentation cystoplasty (AC) in patients with neurogenic bladder. PubMed/MEDLINE was searched for the keywords "augmentation cystoplasty," "neurogenic bladder," and "bladder augmentation." Additional relevant literature was determined by examining the reference lists of articles identified through the search. The update review of of the indications, contraindications, technique, outcome, complications, and tissue engineering approaches of AC in patients with neurogenic bladder is presented. Although some important progress has been made in tissue engineering AC, conventional AC still has an important role in the surgical treatment of refractory neurogenic lower urinary tract dysfunction. PMID:27617312

  19. Augmentation mentoplasty using Mersilene mesh.

    PubMed

    McCollough, E G; Hom, D B; Weigel, M T; Anderson, J R

    1990-10-01

    Many different materials are available for augmentation mentoplasty. However, the optimal implant material for chin implantation has yet to be found. During the past several years, a number of experienced surgeons have turned to the use of Mersilene mesh. Mersilene mesh is a non-absorbable Dacron polyester fiber that can be conformed easily into layers to achieve tailored dimensions and shape. At the McCollough Plastic Surgery Clinic PA, Birmingham, Ala, 277 patients over a 10-year period underwent chin augmentation with Mersilene mesh implants. The material provides excellent tensile strength, durability, and surgical adaptability. The overall complication rate was 3.2% (nine patients); infection rate, 2.5% (seven patients); and removal secondary to infection, 1.7% (five patients). Based on this 10-year experience, Mersilene mesh remains our material of choice for chin augmentation. PMID:2206500

  20. Augmentation cystoplasty in neurogenic bladder

    PubMed Central

    Kocjancic, Ervin; Demirdağ, Çetin

    2016-01-01

    The aim of this review is to update the indications, contraindications, technique, complications, and the tissue engineering approaches of augmentation cystoplasty (AC) in patients with neurogenic bladder. PubMed/MEDLINE was searched for the keywords "augmentation cystoplasty," "neurogenic bladder," and "bladder augmentation." Additional relevant literature was determined by examining the reference lists of articles identified through the search. The update review of of the indications, contraindications, technique, outcome, complications, and tissue engineering approaches of AC in patients with neurogenic bladder is presented. Although some important progress has been made in tissue engineering AC, conventional AC still has an important role in the surgical treatment of refractory neurogenic lower urinary tract dysfunction. PMID:27617312

  1. An overview of current Navy programs to develop thrust augmenting ejectors

    NASA Technical Reports Server (NTRS)

    Green, K. A.

    1979-01-01

    The primary objective of Navy sponsored research in thrust augmentation is the development of an improved augmenter for V/STOL application. In support of this goal, a data base is being established to provide an accurate prediction capability for use in ejector design. A general technology development of ejectors and associated effects presently is split into the more specific areas of lift and control, since thrust augmenting ejectors may be suitable for both. Research areas examined include advanced diffuser and end wall design; advanced primary nozzles; analytic studies; augmenting reaction controls; and nozzle design.

  2. SCUBA: The Self-Contained Unified Bass Augmenter

    NASA Astrophysics Data System (ADS)

    Cceres, Juan Pablo; Mysore, Gautham J.; Trevio, Jeffrey

    2005-04-01

    The Self-Contained Unified Bass Augmenter (SCUBA) is a new augmentative OSC (Open Sound Control) controller for the tuba. SCUBA allows new expressive possibilities by adding onboard continuous and discrete sensors to provide user-controlled parametric data for the processing of the instruments natural sound in Pd. SCUBA endows acoustic instruments with parametric control of virtual instruments and provides a means of integrating the output of a virtual instrument with the natural sound of the tuba. The user sends controller data from the augmented tuba interface to the virtual instrument via FSRs (Force-Sensitive Resistors) and buttons mounted on the existing instrument interface. An AVRMini microcontroller converts raw sensor data to OSC (Open Sound Control) messages, which are mapped in Pd to control virtual instrument parameters. Virtual instrument output is integrated into the solo instrument interface via satellite speakers mounted in the bell; this allows for mixing of the instruments natural sound with that of the virtual instrument to create the impression of a single instrument. This integration is the goal of the SCUBA project: by providing a flexible but unified control interface and acoustic output, traditional acoustic instrument interfaces can be augmented and paired with virtual musical instruments. [We would like to thank Michael Gurevich, Max Matthews, Bill Verplank, Pascal Stang, and classmates from Music 250 (Fall 04) for assistance in the realization of this project.

  3. A Cross-Sectional Study Demonstrating Increased Serum Amyloid A Related Inflammation in High-Density Lipoproteins from Subjects with Type 1 Diabetes Mellitus and How This Association Was Augmented by Poor Glycaemic Control

    PubMed Central

    McEneny, Jane; Daniels, Jane-Ann; McGowan, Anne; Gunness, Anjuli; Moore, Kevin; Stevenson, Michael; Young, Ian S.; Gibney, James

    2015-01-01

    Inflammatory atherosclerosis is increased in subjects with type 1 diabetes mellitus (T1DM). Normally high-density lipoproteins (HDL) protect against atherosclerosis; however, in the presence of serum amyloid-A- (SAA-) related inflammation this property may be reduced. Fasting blood was obtained from fifty subjects with T1DM, together with fifty age, gender and BMI matched control subjects. HDL was subfractionated into HDL2 and HDL3 by rapid ultracentrifugation. Serum-hsCRP and serum-, HDL2-, and HDL3-SAA were measured by ELISAs. Compared to control subjects, SAA was increased in T1DM subjects, nonsignificantly in serum (P = 0.088), and significantly in HDL2(P = 0.003) and HDL3(P = 0.005). When the T1DM group were separated according to mean HbA1c (8.34%), serum-SAA and HDL3-SAA levels were higher in the T1DM subjects with HbA1c ≥ 8.34%, compared to when HbA1c was <8.34% (P < 0.05). Furthermore, regression analysis illustrated, that for every 1%-unit increase in HbA1c, SAA increased by 20% and 23% in HDL2 and HDL3, respectively, independent of BMI. HsCRP did not differ between groups (P > 0.05). This cross-sectional study demonstrated increased SAA-related inflammation in subjects with T1DM that was augmented by poor glycaemic control. We suggest that SAA is a useful inflammatory biomarker in T1DM, which may contribute to their increased atherosclerosis risk. PMID:26557720

  4. Computer Augmented Learning; A Survey.

    ERIC Educational Resources Information Center

    Kindred, J.

    The report contains a description and summary of computer augmented learning devices and systems. The devices are of two general types programed instruction systems based on the teaching machines pioneered by Pressey and developed by Skinner, and the so-called "docile" systems that permit greater user-direction with the computer under student…

  5. Augmenting a Classical Electrochemical Demonstration.

    ERIC Educational Resources Information Center

    Yochum, Susan M.; Luoma, John R.

    1995-01-01

    Presents an augmentation of a classical electrochemical demonstration that addresses the learning styles of the students and teaches electrochemistry in a concrete manner. Enables each student to see each event clearly, repeatedly, or in stop-action mode and enables students to improve their own mental models by providing them with a visually…

  6. Gluteus augmentation with fat grafting.

    PubMed

    Perén, P A; Gómez, J B; Guerrerosantos, J; Salazar, C A

    2000-01-01

    This study presents the authors' experience with gluteus augmentation with autologus fat grafts and liposuction methods, having recorded the evolution of gluteus reshaping with autologus intramuscular fat graft injections for the past 5 years. Preoperative shape is discussed and patient evaluations, operative techniques, postoperative management, and longterm results are emphasized. PMID:11246428

  7. A novel cobiotic containing a prebiotic and an antioxidant augments the glucose control and gastrointestinal tolerability of metformin: a case report.

    PubMed

    Greenway, F; Wang, S; Heiman, M

    2014-03-01

    The gut microbiome plays an important role in regulation of metabolic processes, including digestion, absorption, and synthesis of bioactive molecules that signal physiological host mechanisms. Changes in the human gut microbiome are associated with type 2 diabetes and insulin resistance. Water-soluble dietary fibres like inulin and beta-glucan are fermented in the colon, and beta-glucan increases viscosity. Blueberries improve insulin sensitivity through an antioxidant effect. A cobiotic, consisting of purified inulin, sugar-free blueberry pomace extract, and an oat preparation of purified beta-glucan was developed for twice a day (bid) consumption as a smoothie drink to repair the gastrointestinal dysbiosis in type 2 diabetes. A 30-year-old man presented with new onset type 2 diabetes and a fasting glucose (FBS) of 375 mg/dl. Metformin 500 mg bid was initiated and increased to 1 g bid after 1 week. During the first 9 days of metformin treatment, he developed diarrhoea, but his FBS only dropped to 325 mg/dl. The cobiotic bid was added on the 9th day of metformin treatment, and after 2 days, his FBS dropped to 175 mg/dl. After 8 weeks on metformin and the cobiotic, his blood sugar was 100 mg/dl and he lost 5.5 kg. His stools became soft and formed on the cobiotic, reverted to diarrhoea when off of it for 2 days, and returned to normal on resuming the cobiotic formulation. Metformin is a safe, effective and inexpensive generic medication favouring weight loss, recommended as initial treatment of type 2 diabetes by the American Diabetes Association. However, a 20% incidence of diarrhoea limits its tolerability. A safe food supplement that can increase the efficacy of metformin and its tolerability, as occurred in this case report, would have significant positive public health consequences. A controlled clinical trial of the cobiotic with metformin is planned. PMID:23685372

  8. Controlled release of thymosin beta 4 using a collagen-chitosan sponge scaffold augments cutaneous wound healing and increases angiogenesis in diabetic rats with hindlimb ischemia.

    PubMed

    Ti, Dongdong; Hao, Haojie; Xia, Lei; Tong, Chuan; Liu, Jiejie; Dong, Liang; Xu, Shenjun; Zhao, Yali; Liu, Huiling; Fu, Xiaobing; Han, Weidong

    2015-02-01

    It is important to establish an efficient vascularization for the long-term acceptance of bioengineered skin equivalents treating the cutaneous wounds of diabetic rats with hindlimb ischemia. This study investigates the possible use of a collagen-chitosan sponge scaffold encapsulated with thymosin beta 4 (CCSS-eTβ4), an angiogenic factor, to accelerate cutaneous wound healing in streptozotocin (STZ)-induced diabetic rats with hindlimb ischemia. CCSSs-eTβ4 was fabricated using a freeze-drying method. The scaffolds were analyzed by scanning electron microscopy, swelling and degradation assays, mechanical properties, and scaffolds of 50:50 collagen-chitosan were selected and applied. The controlled release of Tβ4 from the scaffolds elicited localized and prolonged effects over 12 days, as shown by an enzyme-linked immunosorbent assay (ELISA). In vivo, CCSSs-eTβ4 improved diabetic cutaneous wound healing, with faster wound reepithelialization, better dermal reorganization, and higher wound vascularization. Furthermore, CCSSs-eTβ4 downregulated inflammatory genes and upregulated angiogenic genes in the wound tissue. Significant increases in CD31-positive endothelial cells and new vessel density were also observed. In vitro, Tβ4 increased the migratory and proliferative activity of high glucose (HG)-treated human umbilical vein endothelial cells (HUVECs). Meanwhile, we found that Tβ4 could promote HG-treated HUVECs migration and improve angiogenesis by activation of the VEGF/AKT pathway. Overall, these findings demonstrated the promising potential of CCSSs-eTβ4 to promote more effective wound healing and suggest its possible application for diabetic cutaneous wound treatment. PMID:25204972

  9. Augmented-reality-based object modeling in Internet robotics

    NASA Astrophysics Data System (ADS)

    Dalton, Barney; Friz, Harald; Taylor, Kenneth

    1998-12-01

    This paper introduces an Augmented Reality interface that can be used in supervisory control of a robot over the Internet. The operator's client interface requires only a modest computer to run the Java control applet. Operators can completely specify the remote manipulator's path, using an Augmented Realty stick cursor, superimposed on multiple monoscopic images of the workspace. The same cursor is used to identify objects in the workspace, allowing interactive modeling of the workspace environment. Operating place predefined wireframe models of objects on an image of the workspace and use the cursor to align them with corresponding objects in the image.

  10. [Subantral augmentation with porous titanium in experiment and clinic].

    PubMed

    Sirak, S V; Shchetinin, E V; Sletov, A A

    2016-01-01

    The article discusses the use of porous titanium for subantral augmentation. Experimental study was conducted on 12 yearling rams. Subantral augmentation using porous titanium was performed in 33 patients. In the control group consisting of 14 patients calcium phosphates and bone collagen based agents ("Bio-Оss" and "Collost") were used. In the main and control groups 46 and 32 implant were placed, respectively. Pilot histological and clinical studies proved that the granules of porous titanium are biocompatible with bone tissue, provide the optimal surface microrelief, thus creating good conditions for adhesion, expansion and migration of osteoforming cells, have negligible kinetics of resorption, are porous to ensure effective neovascularization of de novo formed bone tissue. Porous titanium is an effective alternative material for subantral bone augmentation for dental implantation and reconstructive operations on the maxillary sinus. PMID:26925568