Science.gov

Sample records for aerial take-off posture

  1. Lightweight Vertical Take-Off & Landing Unmanned Aerial Systems For Local-Scale Forestry and Agriculture Remote Sensing Data Collection

    NASA Astrophysics Data System (ADS)

    Putman, E.; Sheridan, R.; Popescu, S. C.

    2015-12-01

    The evolution of lightweight Vertical Take-Off and Landing (VTOL) rotary Unmanned Aerial Vehicles (UAVs) and remote sensor technologies have provided researchers with the ability to integrate compact remote sensing systems with UAVs to create Unmanned Aerial Systems (UASs) capable of collecting high-resolution airborne remote sensing data. UASs offer a myriad of benefits. Some of the most notable include: (1) reduced operational cost; (2) reduced lead-time for mission planning; (3) high-resolution and high-density data collection; and (4) customization of data collection intervals to fit the needs of a specific project (i.e. acquiring data at hourly, daily, or weekly intervals). Such benefits allow researchers and natural resource managers to acquire airborne remote sensing data on local-scale phenomenon in ways that were previously cost-prohibitive. VTOL UASs also offer a stable platform capable of low speed low altitude flight over small spatial scales that do not require a dedicated runway. Such flight characteristics allow VTOL UASs to collect high-resolution data at very high densities, enabling the use of structure from motion (SFM) techniques to generate three-dimensional datasets from photographs. When combined, these characteristics make VTOL UASs ideal for collecting data over agricultural or forested research areas. The goal of this study is to provide an overview of several lightweight eight-rotor VTOL UASs designed for small-scale forest remote sensing data collection. Specific objectives include: (1) the independent integration of a lightweight multispectral camera, a lightweight scanning lidar sensor, with required components (i.e. IMU, GPS, data logger) and the UAV; (2) comparison of UAS-collected data to terrestrial lidar data and airborne multispectral and lidar data; (3) comparison of UAS SFM techniques to terrestrial lidar data; and (4) multi-temporal assessment of tree decay using terrestrial lidar and UAS SfM techniques.

  2. SR-71 Taking Off

    NASA Technical Reports Server (NTRS)

    1990-01-01

    One of three U.S. Air Force SR-71 reconnaissance aircraft originally retired from operational service and loaned to NASA for a high-speed research program retracts its landing gear after taking off from NASA's Ames-Dryden Flight Research Facility (later Dryden Flight Research Center), Edwards, California, on a 1990 research flight. One of the SR-71As was later returned to the Air Force for active duty in 1995. Data from the SR-71 high-speed research program will be used to aid designers of future supersonic/hypersonic aircraft and propulsion systems. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of

  3. Take-off of heavily loaded airplanes

    NASA Technical Reports Server (NTRS)

    Proll, A

    1928-01-01

    In the present article, several suggestions will be made for shortening the otherwise long take-off distance. For the numerical verification of the process, I will use a graphic method for determining the take-off distance of seaplanes.

  4. The stimuli evoking the aerial-righting posture of falling pea aphids.

    PubMed

    Meresman, Yonatan; Ribak, Gal; Weihs, Daniel; Inbar, Moshe

    2014-10-01

    Some wingless insects possess aerial righting reflexes, suggesting that adaptation for controlling body orientation while falling through air could have preceded flight. When threatened by natural enemies, wingless pea aphids (Acyrthosiphon pisum) may drop off their host plant and assume a stereotypic posture that rotates them in midair to land on their feet. The sensory information triggering aphids to assume this posture has so far been unknown. We subjected aphids to a series of tests, isolating the sensory cues experienced during free-fall. Falling aphids assumed the righting posture and landed upright irrespective of whether the experiments were carried out in the light or in complete darkness. Detachment of the tarsi from the substrate triggered the aphids to assume the posture rapidly, but only for a brief period. Rotation (mainly roll and yaw) of the body in air, in the light, caused aphids to assume the posture and remain in it throughout rotation. In contrast, aphids rotated in the dark did not respond. Acceleration associated with falling or airflow over the body per se did not trigger the posture. However, sensing motion relative to air heightened the aphids' responsiveness to rotation in the light. These results suggest that the righting posture of aphids is triggered by a tarsal reflex, but, once the aphid is airborne, vision and a sense of motion relative to air can augment the response. Hence, aerial righting in a wingless insect could have emerged as a basic tarsal response and developed further to include secondary sensory cues typical of falling. PMID:25104755

  5. Aerodynamics of a beetle in take-off flights

    NASA Astrophysics Data System (ADS)

    Lee, Boogeon; Park, Hyungmin; Kim, Sun-Tae

    2015-11-01

    In the present study, we investigate the aerodynamics of a beetle in its take-off flights based on the three-dimensional kinematics of inner (hindwing) and outer (elytron) wings, and body postures, which are measured with three high-speed cameras at 2000 fps. To track the highly deformable wing motions, we distribute 21 morphological markers and use the modified direct linear transform algorithm for the reconstruction of measured wing motions. To realize different take-off conditions, we consider two types of take-off flights; that is, one is the take-off from a flat ground and the other is from a vertical rod mimicking a branch of a tree. It is first found that the elytron which is flapped passively due to the motion of hindwing also has non-negligible wing-kinematic parameters. With the ground, the flapping amplitude of elytron is reduced and the hindwing changes its flapping angular velocity during up and downstrokes. On the other hand, the angle of attack on the elytron and hindwing increases and decreases, respectively, due to the ground. These changes in the wing motion are critically related to the aerodynamic force generation, which will be discussed in detail. Supported by the grant to Bio-Mimetic Robot Research Center funded by Defense Acquisition Program Administration (UD130070ID).

  6. Take-off and propeller thrust

    NASA Technical Reports Server (NTRS)

    Schrenk, Martin

    1933-01-01

    As a result of previous reports, it was endeavored to obtain, along with the truest possible comprehension of the course of thrust, a complete, simple and clear formula for the whole take-off distance up to a certain altitude, which shall give the correct relative weight to all the factors.

  7. Take-off and landing forces and the evolution of controlled gliding in northern flying squirrels Glaucomys sabrinus.

    PubMed

    Paskins, Keith E; Bowyer, Adrian; Megill, William M; Scheibe, John S

    2007-04-01

    Flying squirrels are well known for their ability to glide between trees at the top of a forest canopy. We present experimental performance and behavioural evidence that flight in flying squirrels may have evolved out of a need to control landing forces. Northern flying squirrels were filmed jumping from a horizontal branch to a much larger vertical pole. These were both slightly compliant (less than 1.9 mm N(-1)), and instrumented using strain gauges so that forces could be measured. Take-off and landing forces were both positively correlated with horizontal range between 0.5 and 2.5 m (r=0.355 and r=0.811, respectively, P<0.05), but not significantly different to each other at each range tested. Take-off forces ranged from 1 to 10 bodyweights, and landing forces were between 3 and 10 bodyweights. Glide angles increased rapidly with horizontal range, approaching 45 degrees at 3 m, above which they gradually decreased, suggesting that northern flying squirrels are optimised for long distance travel. We show that northern flying squirrels initiate full gliding posture at ranges of less than 1 m, without landing any higher than an equivalent ballistic projectile. However, this gliding posture enables them to pitch upwards, potentially stalling the wing, and spreads the landing reaction force over all four extended limbs. At steeper approach angles of close to 45 degrees , flying squirrels were unable to pitch up sufficiently and landed forelimbs first, consequently sustaining higher impact forces. We investigate four hypotheses to explain the origin of flight in these animals and conclude that the need to reduce landing impact forces was most likely to have stimulated the development of aerial control in flying squirrels. PMID:17401124

  8. Take-off distance for airplanes

    NASA Technical Reports Server (NTRS)

    Proll, A

    1926-01-01

    There are two principal ways in which the total take-off distance (taxying plus hovering plus the first part of the climb) can be reduced to a minimum. These are: 1) taxying and hovering until the maximum speed has been attained close to the ground and then changing to a steep rapid climb; 2) lifting the airplane from the ground as soon as possible and then climbing at a relatively large angle of attack. These cases, as well as all the other conceivable combinations, can be expressed with a single basic formula, which is derived from the energy equation for rectilinear flight.

  9. CME Onset and Take-Off

    NASA Technical Reports Server (NTRS)

    Antiochos, S. K.; Karpen, J. T.; DeVore, C. R.

    2011-01-01

    For understanding and eventually predicting coronal mass ejections/eruptive flares, two critical questions must be answered: What is the mechanism for eruption onset, and what is the mechanism for the rapid acceleration? We address these questions in the context of the breakout model using 2.5D MHD simulations with adaptive mesh refinement (AMR). The AMR capability allowed us to achieve ultra-high numerical resolution and, thereby, determine the influence of the effective Lundquist number on the eruption. Our calculations show that, at least, for the breakout model, the onset of reconnection external to the highly sheared filament channel is the onset mechanism. Once this reconnection turns on, eruption is inevitable. However, as long as this is the only reconnection in the system, the eruption remains slow. We find that the eruption undergoes an abrupt "take-off" when the flare reconnection below the erupting plasmoid develops significant reconnection jets. We conclude that in fast CMEs, flare reconnection is the primary mechanism responsible for both flare heating and CME acceleration. We discuss the implications of these results for SDO observations and describe possible tests of the model.

  10. Development of new antibiotics: taking off finally?

    PubMed

    Bettiol, Esther; Harbarth, Stephan

    2015-01-01

    Since 2010, awareness of the global threat caused by antimicrobial resistance (AMR) has risen considerably and multiple policy and research initiatives have been implemented. Research and development (R&D) of much-needed new antibiotics active against multiresistant pathogens is a key component of all programmes aiming at fighting AMR, but it has been lagging behind owing to scientific, regulatory and economic challenges. Although a few new antibiotics might be available in Switzerland in the next 5 years, these new agents are not based on new mechanisms of action and are not necessarily active against resistant pathogens for which there is the highest unmet medical need, i.e. multiresistant Gram-negative bacteria. Of the three new antibiotics with pending authorisation in Switzerland for systemic treatment of severe infections, oritavancin and tedizolid target Gram-positive pathogens, while only ceftolozane+tazobactam partially covers multiresistant Gram-negative pathogens. Among six antibiotics currently in phase III of clinical development, delafloxacin and solithromycin will also be useful mostly for Gram-positive infections. Importantly, the four other compounds are active against multiresistant Gram-negative pathogens: ceftazidime+avibactam, meropenem+RPX7009, eravacycline and plazomicin. The three last compounds are also active against carbapenem-resistant Enterobacteriaceae (CRE). A few compounds active against such pathogens are currently in earlier clinical development, but their number may decrease, considering the risk of failure over the course of clinical development. At last, through public and political awareness of pathogens with high public health impact and unmet medical need, development of innovative economic incentives and updated regulatory guidance, R&D of new antibiotics is slowly taking off again. PMID:26230280

  11. On the take-off of heavily loaded airplanes

    NASA Technical Reports Server (NTRS)

    Breguet, Louis

    1928-01-01

    This report examines the take-off conditions of airplanes equipped with tractive propellers, and particularly the more difficult take-off of airplanes heavily loaded per unit of wing area (wing loading) or per unit of engine power (power loading).

  12. Analysis and Model Tests of Autogiro Jump Take-off

    NASA Technical Reports Server (NTRS)

    Wheatley, John B; Bioletti, Carlton

    1936-01-01

    An analysis is made of the autogiro jump take-off, in which the kinetic energy of the rotor turning at excess speed is used to effect a vertical take-off. By the use of suitable approximations, the differential equation of motion of the rotor during this maneuver is reduced to a form that can be solved. Only the vertical jump was studied; the effect of a forward motion during the jump is discussed briefly. The results of model tests of the jump take-off have been incorporated in the paper and used to establish the relative accuracy of the results predicted from the analysis. Good agreement between calculation and experiment was obtained by making justifiable allowances.

  13. A warning concerning the take-off with heavy load

    NASA Technical Reports Server (NTRS)

    Reid, Elliott G; Carroll, Thomas

    1927-01-01

    A successful take-off can be made with an airplane so heavily loaded that it cannot climb to a height greater than the span of its wings. The explanation is that the power required to maintain level flight at an altitude of the order of the wing span may be as much as 50 per cent greater than that necessary when the airplane is just clear of the ground. The failure of heavily loaded airplanes to continue climbing at the rate attained immediately after the actual take-off is a grave hazard and has resulted in great risk or catastrophe in three notable cases which are cited.

  14. Tick off to Take off: The Pre-Departure Guide

    ERIC Educational Resources Information Center

    Arthur, Erica

    2009-01-01

    "Tick Off to Take Off (TOTTO)" is an online pre-departure guide for UK undergraduates intending to study abroad. It aims to simplify the application process, centralise information, increase efficiency and improve retention rates. TOTTO responds to the changing climate surrounding study abroad in UK universities and offers one way to address calls…

  15. Morphometric relationships of take-off speed in anuran amphibians.

    PubMed

    Choi, Inho; Shim, Jae Han; Ricklefs, Robert E

    2003-10-01

    Locomotory speed correlates with muscle mass (determining force and stride rate), limb length (stride rate and distance), and laterally compressed body trunk (force and stride distance). To delineate generalization of the locomotory-morphometric relationships specifically in anuran amphibians, we investigated take-off speed and the three morphological variables from seven species, Rana nigromaculata, R. rugosa, and Bombina orientalis, Eleuthrodectilus fitzingeri, E. diastema, Bufo typhonius, Colostethus flotator and Physalaemus pustulosus. The fastest jumper E. fitzingeri (3.41 m s(-1)) showed 2.49-fold greater speed than the slowest B. typhonius. Take-off speed correlated well with both thigh muscle mass relative to body mass and hindlimb length relative to snout-vent length (HL/SVL), but poorly correlated with the inter-ilial width relative to SVL. The best morphological predictor was HL/SVL (speed=-3.28+3.916 HL/SVL, r=0.968, P<0.0001), suggesting that anuran take-off speed is portrayed well with high gear and acceleration distance characterized by hindlimbs. PMID:12975797

  16. Characteristics of a Single Float Seaplane During Take-off

    NASA Technical Reports Server (NTRS)

    Crowley, J W , Jr; Ronan, K M

    1925-01-01

    At the request of the Bureau of Aeronautics, Navy Department, the National Advisory Committee for Aeronautics at Langley Field is investigating the get-away characteristics of an N-9H, a DT-2, and an F-5l, as representing, respectively, a single float, a double float, and a boat type of seaplane. This report covers the investigation conducted on the N-9H. The results show that a single float seaplane trims aft in taking off. Until a planing condition is reached the angle of attack is about 15 degrees and is only slightly affected by controls. When planing it seeks a lower angle, but is controllable through a widening range, until at the take-off it is possible to obtain angles of 8 degrees to 15 degrees with corresponding speeds of 53 to 41 M. P. H. or about 40 per cent of the speed range. The point of greatest resistance occurs at about the highest angle of a pontoon planing angle of 9 1/2 degrees and at a water speed of 24 M. P. H.

  17. Whiteflies stabilize their take-off with closed wings.

    PubMed

    Ribak, Gal; Dafni, Eyal; Gerling, Dan

    2016-06-01

    The transition from ground to air in flying animals is often assisted by the legs pushing against the ground as the wings start to flap. Here, we show that when tiny whiteflies (Bemisia tabaci, body length ca. 1 mm) perform take-off jumps with closed wings, the abrupt push against the ground sends the insect into the air rotating forward in the sagittal (pitch) plane. However, in the air, B. tabaci can recover from this rotation remarkably fast (less than 11 ms), even before spreading its wings and flapping. The timing of body rotation in air, a simplified biomechanical model and take-off in insects with removed wings all suggest that the wings, resting backwards alongside the body, stabilize motion through air to prevent somersaulting. The increased aerodynamic force at the posterior tip of the body results in a pitching moment that stops body rotation. Wing deployment increases the pitching moment further, returning the body to a suitable angle for flight. This inherent stabilizing mechanism is made possible by the wing shape and size, in which half of the wing area is located behind the posterior tip of the abdomen. PMID:27045098

  18. Biomechanical and dynamic mechanism of locust take-off

    NASA Astrophysics Data System (ADS)

    Chen, Dian-Sheng; Yin, Jun-Mao; Chen, Ke-Wei; Li, Zhen

    2014-10-01

    The biomimetic locust robot hopping vehicle has promising applications in planet exploration and reconnaissance. This paper explores the bionic dynamics model of locust jumping by using high-speed video and force analysis. This paper applies hybrid rigid-flexible mechanisms to bionic locust hopping and studies its dynamics with emphasis laid on the relationship between force and jumping performance. The hybrid rigid-flexible model is introduced in the analysis of locust mechanism to address the principles of dynamics that govern locust joints and mechanisms during energy storage and take-off. The dynamic response of the biomimetic mechanism is studied by considering the flexibility according to the locust jumping dynamics mechanism. A multi-rigid-body dynamics model of locust jumping is established and analyzed based on Lagrange method; elastic knee and tarsus mechanisms that were proposed in previous works are analyzed alongside the original bionic joint configurations and their machinery principles. This work offers primary theories for take-off dynamics and establishes a theoretical basis for future studies and engineering applications.

  19. Reusable aerospace system with horizontal take-off

    NASA Astrophysics Data System (ADS)

    Lozino-Lozinskii, G. E.; Shkadov, L. M.; Plokhikh, V. P.

    1990-10-01

    An aerospace system (ASS) concept aiming at cost reductions for launching facilities, reduction of ground preparations for start and launch phases, flexibility of use, international inspection of space systems, and emergency rescue operations is presented. The concept suggests the utilization of an AN-225 subsonic carrier aircraft capable of carrying up to 250 ton of the external load, external fuel tank, and orbital spacecraft. It includes a horizontal take-off, full reusable or single-use system, orbital aircraft with hypersonic characteristics, the use of an air-breathing jet engine on the first stage of launch, and the utilization of advanced structural materials. Among possible applications for ASS are satellite launches into low supporting orbits, suborbital cargo and passenger flights, scientific and economic missions, and the technical servicing of orbital vehicles and stations.

  20. Take Off! Aeronautics and Aviation Science: Careers and Opportunities

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Funded by National Aeronautic and Space Administration's High Performance Computing and Communications/ Learning Technologies Project (HPCC/LTP) Cooperative Agreement, Aeronautics and aviation Science: Careers and Opportunities was operative from July 1995 through July 1998. This project operated as a collaboration with Massachusetts Corporation for Educational Telecommunications, the Federal Aviation Administration, Bridgewater State College and four targeted "core sites" in the greater Boston area: Dorchester, Malden, East Boston and Randolph. In its first and second years, a video series with a participatory website on aeronautics and aviation science was developed and broadcast via "live, interactive" satellite feed. Accompanying teacher and student supplementary instructional materials for grades 6-12 were produced and disseminated by the Massachusetts Corporation for Educational Telecommunications (MCET). In year three, the project team redesigned the website, edited 14 videos to a five part thematic unit, and developed a teacher's guide to the video and web materials supplement for MAC and PC platforms, aligned with national standards. In the MCET grant application it states that project Take Off! in its initial phase would recruit and train teachers at "core" sites in the greater Boston area, as well as opening participation to other on-line users of MCET's satellite feeds. "Core site" classrooms would become equipped so that teachers and students might become engaged in an interactive format which aimed at not only involving the students during the "live" broadcast of the instructional video series, but which would encourage participation in electronic information gathering and sharing among participants. As a Take Off! project goal, four schools with a higher than average proportion of minority and underrepresented youth were invited to become involved with the project to give these students the opportunity to consider career exploration and development

  1. Characteristics of a Boat Type Seaplane During Take-off

    NASA Technical Reports Server (NTRS)

    Crowley, J W; Ronan, K M

    1926-01-01

    This report, on the planing and get-away characteristics of the F-5-L, gives the results of the second of a series of take-off tests on three different seaplanes conducted by the National Advisory Committee for Aeronautics at the suggestion of the Bureau of Aeronautics, Navy Department. The single-float seaplane was the first tested and the twin-float seaplane is to be the third. The characteristics of the boat type were found to be similar to the single float, the main difference being the increased sluggishness and relatively larger planing resistance of the larger seaplane. At a water speed of 15 miles per hour the seaplane trims aft to about 12 degrees and remains in this angular position while plowing. At 2.25 miles per hour the planing stage is started and the planing angle is immediately lowered to about 10 degrees. As the velocity increases the longitudinal control becomes more effective but over control will produce instability. At the get-away the range of angle of attack is 19 degrees to 11 degrees with velocities from the stalling speed through about 25 per cent of the speed range.

  2. Altus I aircraft taking off from lakebed runway

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The remotely-piloted Altus I aircraft takes off from Rogers Dry Lake adjacent to NASA's Dryden Flight Research Center, Edwards, Calif. The short series of test flights sponsored by the Naval Postgraduate School in early August, 1997, were designed to demonstrate the ability of the experimental craft to cruise at altitudes above 40,000 feet for sustained durations. On its final flight Aug. 15, the Altus I reached an altitude of 43,500 feet. The Altus I and its sister ship, the Altus II, are variants of the Predator surveillance drone built by General Atomics/Aeronautical Systems, Inc. They are designed for high-altitude, long-duration scientific sampling missions, and are powered by turbocharged piston engines. The Altus I incorporates a single-stage turbocharger, while the Altus II, built for NASA's Environmental Research Aircraft and Sensor Technology program, sports a two-stage turbocharger to enable the craft to fly at altitudes above 55,000 feet.

  3. Analysis of Dragonfly Take-off Mechanism: Initial Impulse Generated by Aerodynamic Forces

    NASA Astrophysics Data System (ADS)

    Zhu, Ruijie; Bode-Oke, Ayodeji; Ren, Yan; Dong, Haibo; Flow Simulation Research Team

    2013-11-01

    Take-off is a critical part of insect flight due to not only that every single flight initiates from take-off, but also that the take-off period, despite its short duration, accounts for a relatively large fraction of the total energy consumption. Thus, studying the mechanism of insect take-off will help to improve the design of Micro Air Vehicles (MAVs) in two major properties, the success rate and the energy efficiency of take-off. In this work, we study 20 cases in which dragonflies (species including Pachydiplax longipennis, Epitheca Cynosura, Epitheca princeps etc.) take off from designed platform. By high-speed photogrammetry, 3-d reconstruction and numerical simulation, we explore how dragonflies coordinate different body parts to help take-off. We evaluate how aerodynamic forces generated by wing flapping create the initial impulse, and how these forces help save energy consumption. Supported by NSF CBET-1343154.

  4. Rans S-12 RPV Takes off with Spacewedge #2

    NASA Technical Reports Server (NTRS)

    1992-01-01

    A Rans S-12 remotely piloted 'mothership' takes off from a lakebed runway carrying a Spacewedge research model during 1992 flight tests. The Spacewedge was lauched in flight from the Rans S-12 aircraft and then glided back to a landing under a steerable parafoil. Technology tested in the Spacewedge program was used in developing the X-38 research vehicle. From October 1991 to December 1996, NASA Ames-Dryden Flight Research Facility (after 1994, the Dryden Flight Research Center, Edwards, California) conducted a research program know as the Spacecraft Autoland Project. This Project was designed to determine the feasibility of the autonomous recovery of a spacecraft using a ram-air parafoil system for the final stages of flight, including a precision landing. The Johnson Space Center and the U.S. Army participated in various phases of the program. The Charles Stark Draper Laboratory developed the software for Wedge 3 under contract to the Army. Four generic spacecraft (each called a Spacewedge or simply a Wedge) were built; the last one was built to test the feasibility of a parafoil for delivering Army cargoes. Technology developed during this program has applications for future spacecraft recovery systems, such as the X-38 Crew Return Vehicle demonstrator. The Spacewedge program demonstrated precision flare and landing into the wind at a predetermined location. The program showed that a flexible, deployable system using autonomous navigation and landing was a viable and practical way to recover spacecraft. NASA researchers conducted flight tests of the Spacewedge at three sites near Dryden, a hillside near Tehachapi, the Rogers Dry Lakebed at Edwards Air Force Base, and the California City Airport Drop Zone. During the first phase of testing 36 flights were made. Phase II consisted of 45 flights using a smaller parafoil. A third Phase of 34 flights was conducted primarily by the Army and resulted in the development of an Army guidance system for precision offset

  5. ROCKETS OR JATO JET ASSISTED TAKE OFF UNITS AT THE HIGH PRESSURE COMBUSTION FACILITY - STATIC FIRING

    NASA Technical Reports Server (NTRS)

    1946-01-01

    ROCKETS OR JATO JET ASSISTED TAKE OFF UNITS AT THE HIGH PRESSURE COMBUSTION FACILITY - STATIC FIRING OF NITRIC ACID ANILINE ROCKET - PERMANGANATE PER OXIDE ROCKET SETUP INCLUDING TWO VIEWS THROUGH CONTROL ROOM SAFETY WINDOW

  6. Influence of determination of reference position of image on rocket take-off drift

    NASA Astrophysics Data System (ADS)

    Cui, Shuhua; Liu, Jun; Shen, Si; Hu, Shaolin

    2016-01-01

    Mathematical analysis model for influence of reference position deviation on carrier rocket take-off drift has been made to tackle the issue on determination of reference position of reticule for optical tracking and measurement of video image in aerospace test range and the variation in rocket take-off drift due to reference position deviation has been subjected to quantitative analysis based on angular error of tracking and lateral error of measuring point as a result of deviation of reference position of reticule cross. The method serves as technical support to quality analysis of rocket take-off deviation measurement data and improvement in data processing precision for carrier rocket take-off drift.

  7. Hybrid vehicle powertrain system with power take-off driven vehicle accessory

    DOEpatents

    Beaty, Kevin D.; Bockelmann, Thomas R.; Zou, Zhanijang; Hope, Mark E.; Kang, Xiaosong; Carpenter, Jeffrey L.

    2006-09-12

    A hybrid vehicle powertrain system includes a first prime mover, a first prime mover driven power transmission mechanism having a power take-off adapted to drive a vehicle accessory, and a second prime mover. The second prime mover is operable to drive the power transmission mechanism alone or in combination with the first prime mover to provide power to the power take-off through the power transmission mechanism. The invention further includes methods for operating a hybrid vehicle powertrain system.

  8. Wing and body motion and aerodynamic and leg forces during take-off in droneflies.

    PubMed

    Chen, Mao Wei; Zhang, Yan Lai; Sun, Mao

    2013-12-01

    Here, we present a detailed analysis of the take-off mechanics in droneflies performing voluntary take-offs. Wing and body kinematics of the insects during take-off were measured using high-speed video techniques. Based on the measured data, the inertia force acting on the insect was computed and the aerodynamic force of the wings was calculated by the method of computational fluid dynamics. Subtracting the aerodynamic force and the weight from the inertia force gave the leg force. In take-off, a dronefly increases its stroke amplitude gradually in the first 10-14 wingbeats and becomes airborne at about the 12th wingbeat. The aerodynamic force increases monotonously from zero to a value a little larger than its weight, and the leg force decreases monotonously from a value equal to its weight to zero, showing that the droneflies do not jump and only use aerodynamic force of flapping wings to lift themselves into the air. Compared with take-offs in insects in previous studies, in which a very large force (5-10 times of the weight) generated either by jumping legs (locusts, milkweed bugs and fruit flies) or by the 'fling' mechanism of the wing pair (butterflies) is used in a short time, the take-off in the droneflies is relatively slow but smoother. PMID:24132205

  9. Wing and body motion and aerodynamic and leg forces during take-off in droneflies

    PubMed Central

    Chen, Mao Wei; Zhang, Yan Lai; Sun, Mao

    2013-01-01

    Here, we present a detailed analysis of the take-off mechanics in droneflies performing voluntary take-offs. Wing and body kinematics of the insects during take-off were measured using high-speed video techniques. Based on the measured data, the inertia force acting on the insect was computed and the aerodynamic force of the wings was calculated by the method of computational fluid dynamics. Subtracting the aerodynamic force and the weight from the inertia force gave the leg force. In take-off, a dronefly increases its stroke amplitude gradually in the first 10–14 wingbeats and becomes airborne at about the 12th wingbeat. The aerodynamic force increases monotonously from zero to a value a little larger than its weight, and the leg force decreases monotonously from a value equal to its weight to zero, showing that the droneflies do not jump and only use aerodynamic force of flapping wings to lift themselves into the air. Compared with take-offs in insects in previous studies, in which a very large force (5–10 times of the weight) generated either by jumping legs (locusts, milkweed bugs and fruit flies) or by the ‘fling’ mechanism of the wing pair (butterflies) is used in a short time, the take-off in the droneflies is relatively slow but smoother. PMID:24132205

  10. Taking off

    ERIC Educational Resources Information Center

    Gorman, Elizabeth

    2012-01-01

    With roots going back to 1986, the Student Team on Alumni Relations or STAR was one of the first student-alumni groups in Canada and routinely attracted capable and enthusiastic volunteers. It offered to appreciative, albeit small, student audiences a suite of popular programs, including job shadowing and goodie boxes parents could send to their…

  11. Thorough warm-up before take-off in honey bee swarms.

    PubMed

    Seeley, Thomas D; Kleinhenz, Marco; Bujok, Brigitte; Tautz, Jürgen

    2003-06-01

    In a bivouacked swarm of honey bees, most individuals are quiescent while a small minority (the scouts) are active in choosing the swarm's future nest site. This study explores the way in which the members of a swarm warm their flight muscles for take-off when the swarm eventually decamps. An infrared camera was used to measure the thoracic (flight muscle) temperatures of individual bees on the surface of a swarm cluster. These are generally the coolest bees in a swarm. The warming of the surface-layer bees occurred mainly in the last 10 min before take-off. By the time a take-off began, 100% of the bees had their flight muscles heated to at least 35 degrees C, which is sufficient to support rapid flight. Take-offs began only a few seconds after all the surface-layer bees had their flight muscles warmed to at least 35 degrees C, but exactly how take-offs are triggered remains a mystery. PMID:12835835

  12. Calculated effect of various types of flap on take-off over obstacles

    NASA Technical Reports Server (NTRS)

    Wetmore, J W

    1936-01-01

    In order to determine whether or not flaps could be expected to have any beneficial effect on take-off performance, the distances required to take off and climb to an altitude of 50 feet were calculated for hypothetical airplanes, corresponding to relatively high-speed types and equipped with several types of flap. The types considered are the Fowler wing, the Hall wing, the split flap, the balanced split flap, the plain flap, and the external-airfoil flap. The results indicate that substantial reductions in take-off distance are possible through the use of flaps, provided that the proper flap angle corresponding to a given set of conditions is used. The best flap angle for taking off varies inversely as power loading and, to a much smaller extent, varies inversely with wing loading. Apparently, the best take-off characteristics are provided by the type of device in which the flap forms an extension to the main wing as in the case of the Fowler wing and the external-airfoil flap.

  13. A Simulator Study of Take-Off Characteristics of Proposed Supersonic Transports

    NASA Technical Reports Server (NTRS)

    Jackson, Charles T., Jr.; Snyder, C. Thomas

    1965-01-01

    Fixed-cockpit piloted simulator studies of delta-planform and variable-wing-sweep supersonic transport configurations are being conducted at the Ames Research Center to investigate the handling qualities and certification requirements related to the take-off maneuver. Validation of the simulation was achieved by duplicating the take-off certification program of a subsonic jet transport. Evaluation of the simulator was made by NASA pilots as well as company and FAA pilots involved in the actual certification flights of the airplane. The present paper is limited to a discussion of normal take-off, minimum control speed (ground), rotation characteristics, and initial climbout. Comparisons of the take-off characteristics are made between the supersonic transport and the current class of subsonic jet transports. Results indicate that minimum control speed (ground) characteristics are a function of thrust-weight ratio, the time provided for SST rotation should be at least as long as that for the subsonic jet transports, abused take-offs are more likely to result in tail scrapes, and climbout below the minimum drag speed requires that the pilot carefully monitor airspeed.

  14. Compliant ankle function results in landing-take off asymmetry in legged locomotion.

    PubMed

    Maykranz, Daniel; Seyfarth, Andre

    2014-05-21

    The spring loaded inverted pendulum (SLIP) model is widely used to predict and explain basic characteristics of human walking and running. Its periodic running solutions can be mirrored at the instant of the vertical orientation of the leg and thus are symmetric between landing and take-off. In contrast, human running shows asymmetries between touchdown and take-off (e.g. shorter brake than push duration, greater mean ground reaction force during braking phase). Yet it is not fully understood whether these asymmetries are caused by asymmetric muscle properties (e.g. velocity-dependent force generation) or the asymmetric lever arm system in the human leg. We extend the SLIP model by a foot segment and a compliant ankle joint. This represents the extended foot contact and the displacement of the center of pressure during contact. With this model we investigate to which extent the landing-take off asymmetry in legged locomotion is caused by this asymmetric lever arm system. We find similar landing-take off asymmetries as in human running suggesting that the asymmetric lever arm system contributes to the asymmetry. PMID:24486249

  15. 40 CFR 1037.525 - Special procedures for testing hybrid vehicles with power take-off.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Special procedures for testing hybrid vehicles with power take-off. 1037.525 Section 1037.525 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW HEAVY-DUTY MOTOR VEHICLES Test and Modeling Procedures §...

  16. 40 CFR 1037.525 - Special procedures for testing hybrid vehicles with power take-off.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Special procedures for testing hybrid vehicles with power take-off. 1037.525 Section 1037.525 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW HEAVY-DUTY MOTOR VEHICLES Test and Modeling Procedures §...

  17. Feasibility study on linear-motor-assisted take-off (LMATO) of winged launch vehicle

    NASA Astrophysics Data System (ADS)

    Nagatomo, Makoto; Kyotani, Yoshihiro

    1987-11-01

    Application of technology of magnetically levitated transportation to horizontal take-off of an experimental space vehicle has been studied. An experimental system of linear-motor-assisted take-off (LMATO) consists of the HIMES space vehicle and a magnetically levitated and propelled sled which is a modified MLU model developed by the JNR. The original MLU model is a train of three cars which weighs 30 tons and is driven by a thrust of 15 tons. The maximum speed is 400 km/h. The highest speed of 517 km/h has been obtained by the first JNR linear motor car. Since the take-off speed of the HIMES vehicle with the initial mass of 14 tons is 470 km/h, the existing technology can be used for the LMATO of the vehicle. The concept of the HIMES/LMATO is to use the MLU vehicles to accelerate the HIMES vehicle at 0.33 g on a 5 km guide track until the speed reaches 300 km/h, when the rocket engines of the space vehicle are started to increase the acceleration up to 1 g. The total system will take the final checkout for take-off during the acceleration phase and the speed exceeds 470 km/h which is large enough to aerodynamically lift the space vehicle, then the fastening mechanism is unlocked to separate the vehicles. The experimental system can be applied for initial acceleration of a vehicle with air-breathing propulsion.

  18. Decorticate posture

    MedlinePlus

    Decorticate posture is an abnormal posturing in which a person is stiff with bent arms, clenched fists, and legs ... Decorticate posture is a sign of damage to the nerve pathway between the brain and spinal cord. Although it ...

  19. The calculated effect of various hydrodynamic and aerodynamic factors on the take-off of a large flying boat

    NASA Technical Reports Server (NTRS)

    Olson, R E; Allison, J M

    1940-01-01

    Report presents the results of an investigation made to determine the influence of various factors on the take-off performance of a hypothetical large flying boat by means of take-off calculations. The factors varied in the calculations were size of hull (load coefficient), wing setting, trim, deflection of flap, wing loading, aspect ratio, and parasite drag. The take-off times and distances were calculated to the stalling speeds and the performance above these speeds was separately studied to determine piloting technique for optimum take-off.

  20. Issues related to aircraft take-off plumes in a mesoscale photochemical model.

    PubMed

    Bossioli, Elissavet; Tombrou, Maria; Helmis, Costas; Kurtenbach, Ralf; Wiesen, Peter; Schäfer, Klaus; Dandou, Aggeliki; Varotsos, Kostas V

    2013-07-01

    The physical and chemical characteristics of aircraft plumes at the take-off phase are simulated with the mesoscale CAMx model using the individual plume segment approach, in a highly resolved domain, covering the Athens International Airport. Emission indices during take-off measured at the Athens International Airport are incorporated. Model predictions are compared with in situ point and path-averaged observations (NO, NO₂) downwind of the runway at the ground. The influence of modeling process, dispersion properties and background air composition on the chemical evolution of the aircraft plumes is examined. It is proven that the mixing properties mainly determine the plume dispersion. The initial plume properties become significant for the selection of the appropriate vertical resolution. Besides these factors, the background NOx and O₃ concentration levels control NOx distribution and their conversion to nitrogen reservoir species. PMID:23584035

  1. Microphysical Properties of Warm Clouds During The Aircraft Take-Off and Landing Over Bucharest, Romania

    NASA Astrophysics Data System (ADS)

    Stefan, Sabina; Nicolae Vajaiac, Sorin; Boscornea, Andreea

    2016-06-01

    This paper is focused on airborne measurements of microphysical parameters into warm clouds when the aircraft penetrates the cloud, both during take-off and landing. The experiment was conducted during the aircraft flight between Bucharest and Craiova, in the southern part of Romania. The duration of the experimental flight was 2 hours and 35 minutes in October 7th, 2014, but the present study is dealing solely with the analysis of cloud microphysical properties at the beginning of the experiment (during the aircraft take-off) and at the end, when it got finalized by the aircraft landing procedure. The processing and interpretation of the measurements showed the differences between microphysical parameters, emphasizing that the type of cloud over Bucharest changed, as it was expected. In addition, the results showed that it is important to take into account both the synoptic context and the cloud perturbation due to the velocity of the aircraft, in such cases.

  2. Wave-actuated power take-off device for electricity generation

    SciTech Connect

    Chertok, Allan

    2013-01-31

    Since 2008, Resolute Marine Energy, Inc. (RME) has been engaged in the development of a rigidly moored shallow-water point absorber wave energy converter, the "3D-WEC". RME anticipated that the 3D-WEC configuration with a fully buoyant point absorber buoy coupled to three power take off (PTO) units by a tripod array of tethers would achieve higher power capture than a more conventional 1-D configuration with a single tether and PTO. The investigation conducted under this program and documented herein addressed the following principal research question regarding RME's power take off (PTO) concept for its 3D-WEC: Is RME's winch-driven generator PTO concept, previously implemented at sub-scale and tested at the Ohmsett wave tank facility, scalable in a cost-effective manner to significant power levels e.g., 10 to 100kW?

  3. Requirements report for SSTO vertical take-off and horizontal landing vehicle

    NASA Technical Reports Server (NTRS)

    Greenberg, H. S.

    1994-01-01

    This document describes the detailed design requirements and design criteria to support Structures/TPS Technology development for SSTO winged vehicle configurations that use vertical take-off and horizontal landing and delivers 25,000 lb payloads to a 220 nm circular orbit at an inclination of 51.6 degrees or 40,000 lb payloads to a 150 nm circular orbit at a 28.5 degree inclination.

  4. Linear kinematics at take-off in horses jumping the wall in an international Puissance competition.

    PubMed

    Powers, Pippa

    2005-07-01

    Sagittal plane SVHS video recordings (50 Hz) were made of horses jumping the wall at an international Puissance competition. Video sequences were manually digitized and six kinematic variables at take-off were analyzed. Nine horses started the competition with the fence height at 1.80 m, and two horses attempted the fence in the fifth and final round with the fence height at 2.27 m. For successful performances, fence height was correlated with the following take-off variables: vertical velocity of the centre of mass (r = 0.45, p = 0.03); height of centre of mass (r = 0.44, p = 0.04); distance of centre of mass from fence (r = 0.46, p = 0.03); and distance from leading hind limb to centre of mass (r = -0.61, p < 0.01). These results indicated that body position at take-off is the most important aspect when jumping high fences. This is the first known study that has examined horses jumping over a Puissance wall. The results should help horse riders and trainers improve performance in Puissance jumping horses, and perhaps help in the early selection of horses with a talent for jumping high fences. PMID:16138654

  5. Airport take-off noise assessment aimed at identify responsible aircraft classes.

    PubMed

    Sanchez-Perez, Luis A; Sanchez-Fernandez, Luis P; Shaout, Adnan; Suarez-Guerra, Sergio

    2016-01-15

    Assessment of aircraft noise is an important task of nowadays airports in order to fight environmental noise pollution given the recent discoveries on the exposure negative effects on human health. Noise monitoring and estimation around airports mostly use aircraft noise signals only for computing statistical indicators and depends on additional data sources so as to determine required inputs such as the aircraft class responsible for noise pollution. In this sense, the noise monitoring and estimation systems have been tried to improve by creating methods for obtaining more information from aircraft noise signals, especially real-time aircraft class recognition. Consequently, this paper proposes a multilayer neural-fuzzy model for aircraft class recognition based on take-off noise signal segmentation. It uses a fuzzy inference system to build a final response for each class p based on the aggregation of K parallel neural networks outputs Op(k) with respect to Linear Predictive Coding (LPC) features extracted from K adjacent signal segments. Based on extensive experiments over two databases with real-time take-off noise measurements, the proposed model performs better than other methods in literature, particularly when aircraft classes are strongly correlated to each other. A new strictly cross-checked database is introduced including more complex classes and real-time take-off noise measurements from modern aircrafts. The new model is at least 5% more accurate with respect to previous database and successfully classifies 87% of measurements in the new database. PMID:26540603

  6. VIDEO REVIEW: Maths in a Box video: Take-off - moving bodies with constant mass

    NASA Astrophysics Data System (ADS)

    Marks, Ken

    1999-09-01

    I write this review as a PGCE maths tutor, and therefore from the perspective of using parts of this series at A-level. The sample video, `Take-off - moving bodies with constant mass', is a good example of combining real footage with commentary as the viewer is invited to think about modelling the take-off of an aircraft. The style is reminiscent of Open University presentations and here the challenge is to determine the necessary length of the runway. The video is split into two sections. The first, commentary, section works quite well, although it jars a bit to hear Newton's Third Law put across as `Action and reaction are equal and opposite'; this is a familiar offering but one that still causes mystification in the sixth form. The viewer is invited to think about setting up equations, and reminded that the chain rule will be necessary to solve the differential equation generated from Newton's Second Law. This gives a good indication of the level of mathematics required. Unfortunately the flow is then somewhat disturbed by a strong emphasis on boundary conditions. If the student can cope with the general level of calculus required, this aspect of the challenge would also seem to fit more naturally into the second section of the video. This second section looks at setting up the equations and `solutions'. It can be used after classroom discussion, and takes the viewer through three, increasingly sophisticated, models involving functions for drag and resistance forces. On the whole this is clear and helpful, but for some reason the solutions each stop with an equation linking the length of the runway to the take-off velocity, failing to make use of the second equation to eliminate this intermediate variable. All in all, it is a useful addition to resources for A-level, particularly if students are also following the sort of mechanics syllabus (within mathematics) that emphasizes modelling.

  7. Requirements report for SSTO vertical take-off/horizontal landing vehicle

    NASA Technical Reports Server (NTRS)

    Greenberg, H. S.

    1994-01-01

    This document describes the detailed design requirements and design criteria to support Structures/TPS Technology development for SSTO winged vehicle configurations that use vertical take-off and horizontal landing and deliver 25,000 lb payloads to a 220 nm circular orbit at an inclination of 51.6 degrees or 40,000 lb payloads to a 150 nm circular orbit at a 28.5 degree of inclination. This document will be updated on a timely basis as informatIon becomes available throughout the project.

  8. Magnetic levitation assisted aircraft take-off and landing (feasibility study - GABRIEL concept)

    NASA Astrophysics Data System (ADS)

    Rohacs, Daniel; Rohacs, Jozsef

    2016-08-01

    The Technology Roadmap 2013 developed by the International Air Transport Association envisions the option of flying without an undercarriage to be in operation by 2032. Preliminary investigations clearly indicate that magnetic levitation technology (MagLev) might be an appealing solution to assist the aircraft take-off and landing. The EU supported research project, abbreviated as GABRIEL, was dealing with (i) the concept development, (ii) the identification, evaluation and selection of the deployable magnetic levitation technology, (iii) the definition of the core system elements (including the required aircraft modifications, the ground-based system and airport elements, and the rendezvous control system), (iv) the analysis of the safety and security aspects, (v) the concept validation and (vi) the estimation of the proposed concept impact in terms of aircraft weight, noise, emission, cost-benefit). All results introduced here are compared to a medium size hypothetic passenger aircraft (identical with an Airbus A320). This paper gives a systematic overview of (i) the applied methods, (ii) the investigation of the possible use of magnetic levitation technology to assist the commercial aircraft take-off and landing processes and (iii) the demonstrations, validations showing the feasibility of the radically new concept. All major results are outlined.

  9. Low Noise Cruise Efficient Short Take-Off and Landing Transport Vehicle Study

    NASA Technical Reports Server (NTRS)

    Kim, Hyun D.; Berton, Jeffrey J.; Jones, Scott M.

    2007-01-01

    The saturation of the airspace around current airports combined with increasingly stringent community noise limits represents a serious impediment to growth in world aviation travel. Breakthrough concepts that both increase throughput and reduce noise impacts are required to enable growth in aviation markets. Concepts with a 25 year horizon must facilitate a 4x increase in air travel while simultaneously meeting community noise constraints. Attacking these horizon issues holistically is the concept study of a Cruise Efficient Short Take-Off and Landing (CESTOL) high subsonic transport under the NASA's Revolutionary Systems Concepts for Aeronautics (RSCA) project. The concept is a high-lift capable airframe with a partially embedded distributed propulsion system that takes a synergistic approach in propulsion-airframe-integration (PAI) by fully integrating the airframe and propulsion systems to achieve the benefits of both low-noise short take-off and landing (STOL) operations and efficient high speed cruise. This paper presents a summary of the recent study of a distributed propulsion/airframe configuration that provides low-noise STOL operation to enable 24-hour use of the untapped regional and city center airports to increase the capacity of the overall airspace while still maintaining efficient high subsonic cruise flight capability.

  10. Validation of an Active Gear, Flexible Aircraft Take-off and Landing analysis (AGFATL)

    NASA Technical Reports Server (NTRS)

    Mcgehee, J. R.

    1984-01-01

    The results of an analytical investigation using a computer program for active gear, flexible aircraft take off and landing analysis (AGFATL) are compared with experimental data from shaker tests, drop tests, and simulated landing tests to validate the AGFATL computer program. Comparison of experimental and analytical responses for both passive and active gears indicates good agreement for shaker tests and drop tests. For the simulated landing tests, the passive and active gears were influenced by large strut binding friction forces. The inclusion of these undefined forces in the analytical simulations was difficult, and consequently only fair to good agreement was obtained. An assessment of the results from the investigation indicates that the AGFATL computer program is a valid tool for the study and initial design of series hydraulic active control landing gear systems.

  11. Taxiing, Take-Off, and Landing Simulation of the High Speed Civil Transport Aircraft

    NASA Technical Reports Server (NTRS)

    Reaves, Mercedes C.; Horta, Lucas G.

    1999-01-01

    The aircraft industry jointly with NASA is studying enabling technologies for higher speed, longer range aircraft configurations. Higher speeds, higher temperatures, and aerodynamics are driving these newer aircraft configurations towards long, slender, flexible fuselages. Aircraft response during ground operations, although often overlooked, is a concern due to the increased fuselage flexibility. This paper discusses modeling and simulation of the High Speed Civil Transport aircraft during taxiing, take-off, and landing. Finite element models of the airframe for various configurations are used and combined with nonlinear landing gear models to provide a simulation tool to study responses to different ground input conditions. A commercial computer simulation program is used to numerically integrate the equations of motion and to compute estimates of the responses using an existing runway profile. Results show aircraft responses exceeding safe acceptable human response levels.

  12. Adaptive Data-based Predictive Control for Short Take-off and Landing (STOL) Aircraft

    NASA Technical Reports Server (NTRS)

    Barlow, Jonathan Spencer; Acosta, Diana Michelle; Phan, Minh Q.

    2010-01-01

    Data-based Predictive Control is an emerging control method that stems from Model Predictive Control (MPC). MPC computes current control action based on a prediction of the system output a number of time steps into the future and is generally derived from a known model of the system. Data-based predictive control has the advantage of deriving predictive models and controller gains from input-output data. Thus, a controller can be designed from the outputs of complex simulation code or a physical system where no explicit model exists. If the output data happens to be corrupted by periodic disturbances, the designed controller will also have the built-in ability to reject these disturbances without the need to know them. When data-based predictive control is implemented online, it becomes a version of adaptive control. The characteristics of adaptive data-based predictive control are particularly appropriate for the control of nonlinear and time-varying systems, such as Short Take-off and Landing (STOL) aircraft. STOL is a capability of interest to NASA because conceptual Cruise Efficient Short Take-off and Landing (CESTOL) transport aircraft offer the ability to reduce congestion in the terminal area by utilizing existing shorter runways at airports, as well as to lower community noise by flying steep approach and climb-out patterns that reduce the noise footprint of the aircraft. In this study, adaptive data-based predictive control is implemented as an integrated flight-propulsion controller for the outer-loop control of a CESTOL-type aircraft. Results show that the controller successfully tracks velocity while attempting to maintain a constant flight path angle, using longitudinal command, thrust and flap setting as the control inputs.

  13. Fatiguing effect of multiple take-offs and landings in regional airline operations.

    PubMed

    Honn, Kimberly A; Satterfield, Brieann C; McCauley, Peter; Caldwell, J Lynn; Van Dongen, Hans P A

    2016-01-01

    Fatigue is a risk factor for flight performance and safety in commercial aviation. In US commercial aviation, to help to curb fatigue, the maximum duration of flight duty periods is regulated based on the scheduled start time and the number of flight segments to be flown. There is scientific support for regulating maximum duty duration based on scheduled start time; fatigue is well established to be modulated by circadian rhythms. However, it has not been established scientifically whether the number of flight segments, per se, affects fatigue. To address this science gap, we conducted a randomized, counterbalanced, cross-over study with 24 active-duty regional airline pilots. Objective and subjective fatigue was compared between a 9-hour duty day with multiple take-offs and landings versus a duty day of equal duration with a single take-off and landing. To standardize experimental conditions and isolate the fatiguing effect of the number of segments flown, the entire duty schedules were carried out in a high-fidelity, moving-base, full-flight, regional jet flight simulator. Steps were taken to maintain operational realism, including simulated airplane inspections and acceptance checks, use of realistic dispatch releases and airport charts, real-world air traffic control interactions, etc. During each of the two duty days, 10 fatigue test bouts were administered, which included a 10-minute Psychomotor Vigilance Test (PVT) assessment of objective fatigue and Samn-Perelli (SP) and Karolinska Sleepiness Scale (KSS) assessments of subjective sleepiness/fatigue. Results showed a greater build-up of objective and subjective fatigue in the multi-segment duty day than in the single-segment duty day. With duty start time and duration and other variables that could impact fatigue levels held constant, the greater build-up of fatigue in the multi-segment duty day was attributable specifically to the difference in the number of flight segments flown. Compared to findings in

  14. Quiet Cruise Efficient Short Take-off and Landing Subsonic Transport System

    NASA Technical Reports Server (NTRS)

    Kawai, Ron

    2008-01-01

    This NASA funded study conceived a revolutionary airplane concept to enable future traffic growth by using regional air space. This requires a very quiet airplane with STOL capability. Starting with a Blended Wing Body that is cruise efficient with inherent low noise characteristics from forward noise shielding and void of aft downward noise reflections, integration of embedded distributed propulsion enables incorporation of the revolutionary concept for jet noise shielding. Embedded distributed propulsion also enables incorporation of a fan bleed internally blown flap for quiet powered lift. The powered lift provides STOL capability for operation at regional airports with rapid take-off and descent to further reduce flyover noise. This study focused on configuring the total engine noise shielding STOL concept with a BWB airplane using the Boeing Phantom Works WingMOD multidisciplinary optimization code to define a planform that is pitch controllable. The configuration was then sized and mission data developed to enable NASA to assess the flyover and sideline noise. The foundational technologies needed are identified including military dual use benefits.

  15. Stability analysis of the Gyroscopic Power Take-Off wave energy point absorber

    NASA Astrophysics Data System (ADS)

    Nielsen, Søren R. K.; Zhang, Zili; Kramer, Morten M.; Olsen, Jan

    2015-10-01

    The Gyroscopic Power Take-Off (GyroPTO) wave energy point absorber consists of a float rigidly connected to a lever. The operational principle is somewhat similar to that of the so-called gyroscopic hand wrist exercisers, where the rotation of the float is brought forward by the rotational particle motion of the waves. At first, the equations of motion of the system are derived based on analytical rigid body dynamics. Next, assuming monochromatic waves simplified equations are derived, valid under synchronisation of the ring of the gyro to the angular frequency of the excitation. Especially, it is demonstrated that the dynamics of the ring can be described as an autonomous nonlinear single-degree-of-freedom system, affected by three different types of point attractors. One where the ring vibrations are attracted to a static equilibrium point indicating unstable synchronisation and two types of attractors where the ring is synchronised to the wave angular frequency, either rotating in one or the opposite direction. Finally, the stability conditions and the basins of attraction to the point attractors defining the synchronised motion are determined.

  16. Measurement of the Errors of Service Altimeter Installations During Landing-Approach and Take-Off Operations

    NASA Technical Reports Server (NTRS)

    Gracey, William; Jewel, Joseph W., Jr.; Carpenter, Gene T.

    1960-01-01

    The overall errors of the service altimeter installations of a variety of civil transport, military, and general-aviation airplanes have been experimentally determined during normal landing-approach and take-off operations. The average height above the runway at which the data were obtained was about 280 feet for the landings and about 440 feet for the take-offs. An analysis of the data obtained from 196 airplanes during 415 landing approaches and from 70 airplanes during 152 take-offs showed that: 1. The overall error of the altimeter installations in the landing- approach condition had a probable value (50 percent probability) of +/- 36 feet and a maximum probable value (99.7 percent probability) of +/- 159 feet with a bias of +10 feet. 2. The overall error in the take-off condition had a probable value of +/- 47 feet and a maximum probable value of +/- 207 feet with a bias of -33 feet. 3. The overall errors of the military airplanes were generally larger than those of the civil transports in both the landing-approach and take-off conditions. In the landing-approach condition the probable error and the maximum probable error of the military airplanes were +/- 43 and +/- 189 feet, respectively, with a bias of +15 feet, whereas those for the civil transports were +/- 22 and +/- 96 feet, respectively, with a bias of +1 foot. 4. The bias values of the error distributions (+10 feet for the landings and -33 feet for the take-offs) appear to represent a measure of the hysteresis characteristics (after effect and recovery) and friction of the instrument and the pressure lag of the tubing-instrument system.

  17. Research and application of a new kind of measurement technology of take-off and landing performance

    NASA Astrophysics Data System (ADS)

    Chunbao, Yang

    A video-based take-off and landing performance measurement system has been developed to aid in certification of the Y-12 aircraft. The system has high accuracy and is adaptable to computer analysis. Employing dual channel audio inputs, and the video system is capable of coordinating such synchronous signals as IRIG B time code and voice with flight data obtained using an airborne data acquisition system. Applications of the system include searching for the best take-off and landing flight path, the establishment of helicopter hovering capacity, and fly-over noise evaluation.

  18. Validation of Self-Reported Power Take-Off Shielding Using On-Site Farm Audits.

    PubMed

    Chapel, D B; Sorensen, J A; Tinc, P J; Fiske, T; Wyckoff, S; Mellors, P W; Jenkins, P

    2015-04-01

    Despite the substantial contribution of power take-off (PTO) entanglements to workplace morbidity and mortality among agricultural workers, the degree of proper PTO shielding on U.S. farms remains poorly characterized. Sampling from the New York data of the USDA National Agricultural Statistical Service (NASS), at least 200 each of dairy, livestock, crop, fruit, and vegetable farms were surveyed by phone to determine the extent of proper PTO shielding. In the same year, on-site audits were performed at 211 randomly selected New York livestock and dairy farms using a four-point scale to assess PTO shielding. Supplemental data were gathered on farm acreage, number of livestock, principal commodity, and operator experience. The phone survey data for livestock and dairy farms were then compared to the on-farm audit data. In the phone survey, 72.5% of farms reported having shields on all implements. The mean percentage of implements reported to be shielded was 90.2%. By on-farm audit, 10% of farms had all implements properly shielded, and the mean percentage of properly shielded implements was 56.7%, with shielding rates differing widely for different classes of implements. No significant predictors of PTO shielding were identified. The phone survey greatly overestimated proper PTO shielding rates when compared with the on-farm audits. These data suggest a lower level of proper shielding among farmers than is mandated by current industry safety standards. The results also identify a principal weakness of phone surveys in accurately assessing the true magnitude of on-farm risk for PTO entanglement. PMID:26204785

  19. Decerebrate posture

    MedlinePlus

    ... Brain problem due to drugs, poisoning, or infection Head injury Brain problem due to liver failure Increased pressure ... of posture? Is there any history of a head injury or other condition? What other symptoms came before ...

  20. Final Scientific/Technical Report: ADVANCED INTEGRATION OF POWER TAKE-OFF IN VIVACE

    SciTech Connect

    Simiao, Gustavo

    2014-03-21

    Vortex Hydro Energy is commercializing a University of Michigan patented MHK device, the VIVACE converter (Vortex Induced Vibration Aquatic Clean Energy). Unlike water turbines, it does not use propeller blades. Rather, river or ocean currents flow around cylinders causing them to move up and down in Flow Induced Motions (FIM). This kinetic energy of the cylinder is then converted to electricity. Importantly, the VIVACE converter is simpler in design and more cost effective than water turbines. This project accelerated the development of the VIVACE technology. Funding from the DOE enabled VHE to accelerate the development in three ways. One was to increase the efficiency of the hydrodynamics of the system. This aided in maximizing the power output for a wide range of water speeds. The second was to design, build, and test an efficient power take-off (PTO) that converted the most power from the VIVACE cylinders into electricity. This effort was necessary because of the nature of power generated using this technology. Although the PTO uses off-the-shelf components, it is specifically tuned to the specific water flow characteristics. The third way the development was accelerated was by testing the improved Beta 1B prototype over a longer period of time in a river. The greatest benefit from the longer open-water testing-period is a better understand of the power generation characteristics of the system as well as the maintenance lifespan of the device. Renewable energy generation is one of today’s most challenging global dilemmas. The energy crisis requires tapping into every source of energy and developing every technology that can generate energy at a competitive cost within the next 50 years. Development of VIVACE will bolster domestic energy security and mitigate global climate change. There are numerous commercial and military applications for a fully developed system, which could generate clean/renewable energy from small scale (1-5kW) to medium scale (500k

  1. How is the brain working?: Research on brain oscillations and connectivities in a new "Take-Off" state.

    PubMed

    Başar, Erol; Düzgün, Aysel

    2016-05-01

    The present report is a trial to survey analysis and applications of brain oscillations in cognitive impairment for opening the way to a new take off in research on brain oscillation. Although the number of papers related to brain oscillations rapidly increases, it is important to indicate the common principles governing the functioning of brain oscillations in the brain and body. Research scientists need a global view on the types of analysis, applications and existing oscillations. Further, scientists dealing with brain oscillations must have some knowledge from theoretical physics, system theory, and also general philosophy. The neuroscientists working on brain oscillations can mentally integrate several papers in the present report, and try to discover new avenues to augment knowledge on brain functions. A new take off in the search of brain oscillations indicates the strong need to survey this brunch of neuroscience in a broad panoply of science. PMID:25660309

  2. Probabilistic model, analysis and computer code for take-off and landing related aircraft crashes into a structure

    SciTech Connect

    Glaser, R.

    1996-02-06

    A methodology is presented that allows the calculation of the probability that any of a particular collection of structures will be hit by an aircraft in a take-off or landing related accident during a specified window of time with a velocity exceeding a given critical value. A probabilistic model is developed that incorporates the location of each structure relative to airport runways in the vicinity; the size of the structure; the sizes, types, and frequency of use of commercial, military, and general aviation aircraft which take-off and land at these runways; the relative frequency of take-off and landing related accidents by aircraft type; the stochastic properties of off-runway crashes, namely impact location, impact angle, impact velocity, and the heading, deceleration, and skid distance after impact; and the stochastic properties of runway overruns and runoffs, namely the position at which the aircraft exits the runway, its exit velocity, and the heading and deceleration after exiting. Relevant probability distributions are fitted from extensive commercial, military, and general aviation accident report data bases. The computer source code for implementation of the calculation is provided.

  3. Take-off speed in jumping mantises depends on body size and a power-limited mechanism.

    PubMed

    Sutton, G P; Doroshenko, M; Cullen, D A; Burrows, M

    2016-07-15

    Many insects such as fleas, froghoppers and grasshoppers use a catapult mechanism to jump, and a direct consequence of this is that their take-off velocities are independent of their mass. In contrast, insects such as mantises, caddis flies and bush crickets propel their jumps by direct muscle contractions. What constrains the jumping performance of insects that use this second mechanism? To answer this question, the jumping performance of the mantis Stagmomantis theophila was measured through all its developmental stages, from 5 mg first instar nymphs to 1200 mg adults. Older and heavier mantises have longer hind and middle legs and higher take-off velocities than younger and lighter mantises. The length of the propulsive hind and middle legs scaled approximately isometrically with body mass (exponent=0.29 and 0.32, respectively). The front legs, which do not contribute to propulsion, scaled with an exponent of 0.37. Take-off velocity increased with increasing body mass (exponent=0.12). Time to accelerate increased and maximum acceleration decreased, but the measured power that a given mass of jumping muscle produced remained constant throughout all stages. Mathematical models were used to distinguish between three possible limitations to the scaling relationships: first, an energy-limited model (which explains catapult jumpers); second, a power-limited model; and third, an acceleration -: limited model. Only the model limited by muscle power explained the experimental data. Therefore, the two biomechanical mechanisms impose different limitations on jumping: those involving direct muscle contractions (mantises) are constrained by muscle power, whereas those involving catapult mechanisms are constrained by muscle energy. PMID:27284067

  4. Maximizing height, distance or rotation from real-time analysis visualisation of take-off angles and speed.

    PubMed

    Green, Richard

    2006-01-01

    Studies to optimise take off angles for height or distance have usually involved either a time-consuming invasive approach of placing markers on the body in a laboratory setting or using even less efficient manual frame-by-frame joint angle calculations with one of the many sport science video analysis software tools available. This research introduces a computer-vision based, marker-free, real-time biomechanical analysis approach to optimise take-off angles based on speed, base of support and dynamically calculated joint angles and mass of body segments. The goal of a jump is usually for height, distance or rotation with consequent dependencies on speed and phase of joint angles, centre of mass COM) and base of support. First and second derivatives of joint angles and body part COMs are derived from a Continuous Human Movement Recognition (CHMR) system for kinematical and what-if calculations. Motion is automatically segmented using hierarchical Hidden Markov Models and 3D tracking is further stabilized by estimating the joint angles for the next frame using a forward smoothing Particle filter. The results from a study of jumps, leaps and summersaults supporting regular knowledge of results feedback during training sessions indicate that this approach is useful for optimising the height, distance or rotation of skills. Key PointsComputer-vision based marker-free tracking.Real-time biomechanical analysis.Improve tracking using a forward smoothing Particle filter.Automatically segment using hierarchical Hidden Markov Models.Recognize skills using segmented motion.Optimize take-off angles using speed, base of support, joint angles and mass of body segments.Optimize height, distance or rotation of skills. PMID:24357954

  5. Take-off speed in jumping mantises depends on body size and a power-limited mechanism

    PubMed Central

    Doroshenko, M.; Cullen, D. A.; Burrows, M.

    2016-01-01

    ABSTRACT Many insects such as fleas, froghoppers and grasshoppers use a catapult mechanism to jump, and a direct consequence of this is that their take-off velocities are independent of their mass. In contrast, insects such as mantises, caddis flies and bush crickets propel their jumps by direct muscle contractions. What constrains the jumping performance of insects that use this second mechanism? To answer this question, the jumping performance of the mantis Stagmomantis theophila was measured through all its developmental stages, from 5 mg first instar nymphs to 1200 mg adults. Older and heavier mantises have longer hind and middle legs and higher take-off velocities than younger and lighter mantises. The length of the propulsive hind and middle legs scaled approximately isometrically with body mass (exponent=0.29 and 0.32, respectively). The front legs, which do not contribute to propulsion, scaled with an exponent of 0.37. Take-off velocity increased with increasing body mass (exponent=0.12). Time to accelerate increased and maximum acceleration decreased, but the measured power that a given mass of jumping muscle produced remained constant throughout all stages. Mathematical models were used to distinguish between three possible limitations to the scaling relationships: first, an energy-limited model (which explains catapult jumpers); second, a power-limited model; and third, an acceleration-limited model. Only the model limited by muscle power explained the experimental data. Therefore, the two biomechanical mechanisms impose different limitations on jumping: those involving direct muscle contractions (mantises) are constrained by muscle power, whereas those involving catapult mechanisms are constrained by muscle energy. PMID:27284067

  6. Performance and technological feasibility of rocket powered HTHL-SSTO with take-off assist (aerospace plane/ekranoplane)

    NASA Astrophysics Data System (ADS)

    Tomita, Nobuyuki; Nebylov, Alexander V.; Sokolov, Victor V.; Ohkami, Yoshiaki

    It might be said that it is common understanding that rocket-powered single stage to orbit (SSTO) aerospace planes will become feasible with near-term technology as described in [1] (Koelle, D. E. Survey and comparison of winged launch vehicle options, ISTS 94-g-11 V 1994) and [2] (Bekey, I. Why SSTO rocket launch vehicles are now feasible and practical, IAF-94-V.1.524 1994). Among two methods of launching aerospace planes into orbit, vertical take-off (VT) and horizontal take-off (HT), it seems that VT takes the lead from HT [1, 2]. The decision for the X-33 program by NASA, also, seems to favor VT. In retrospect, almost all of the launch vehicles in the past have been VT, mainly because VT solved the problem of exit from atmosphere to space. However, broadening the range of requirements for space transportation systems from military to commercial and unmanned to manned seems to favor the need for HT. In this paper, the authors are going to prove that aerospace plane/ekranoplane system, which is a reusable launch vehicle system based on the HT concept, with ekranoplane as a take-off and possibly, landing assist, could be competitive with the VT concept from both technological and economical view points. Ekranoplane is a wing-in-ground-effect craft (WIG), which moves at a speed of approximately 0.5 M, carrying heavy loads above the sea surface. Combination of high initial velocity and high performance tri-propellant engine for aerospace plane makes it possible to configure an aerospace plane which is competitive with VT. Other specific features of HT in comparison with VT are discussed.

  7. Flight take-off and walking behavior of insecticide-susceptible and - resistant strains of Sitophilus zeamais exposed to deltamethrin.

    PubMed

    Guedes, N M P; Guedes, R N C; Ferreira, G H; Silva, L B

    2009-08-01

    Insects have evolved a variety of physiological and behavioral responses to various toxins in natural and managed ecosystems. However, insect behavior is seldom considered in insecticide studies although insects are capable of changing their behavior in response to their sensory perception of insecticides, which may compromise insecticide efficacy. This is particularly serious for insect pests that are physiologically resistant to insecticides since insecticide avoidance may further compromise their management. Locomotion plays a major role determining insecticide exposure and was, therefore, considered in investigating the behavioral responses of male and female adult insects from an insecticide-susceptible and two insecticide-resistant strains of the maize weevil Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), a major pest of stored cereals. Different dose-dependent behavioral responses were expected among strains with behavioral resistance less likely to occur in physiologically resistant insects since they are able to withstand higher doses of insecticide. The behavioral responses to deltamethrin-sprayed surfaces differed among the maize weevil strains. Such responses were concentration-independent for all of the strains. Stimulus-independent behavioral resistance was unrelated to physiological resistance with one resistant strain exhibiting higher rates of flight take-off and the other resistant strain exhibiting lower flight take-off. Female mobility was similar for all strains, unlike male mobility. Males of each strain exhibited a pattern of mobility following the same trend of flight take-off. Behavioral patterns of response to insecticide are, therefore, variable among strains, particularly among insecticide-resistant strains, and worth considering in resistance surveys and management programs. PMID:19302721

  8. F-16XL ship #1 (#849) takes off for first flight of the Digital Flight Control System (DFCS)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The F-16XL #1 (NASA 849) takes off for the first flight of the Digital Flight Control System (DFCS) on December 16, 1997. Like most first flight, the DFCS required months of preparations. During July 1997, crews worked on the engine, cockpit, canopy, seat, and instrumentation. By late August, the aircraft began combined systems tests and a flight readiness review. Although the Air Force Safety Review Board (AFSRB)- a group that provided double checks on all flight operations - approved the program in late November 1997, a problem with the aircraft flight computer delayed the functional check flight until mid-December.

  9. The Rolling Friction of Several Airplane Wheels and Tires and the Effect of Rolling Friction on Take-Off

    NASA Technical Reports Server (NTRS)

    Wetmore, J W

    1937-01-01

    This report presents the results of test made to determine the rolling friction of airplane wheels and tires under various conditions of wheel loading, tire inflation pressure, and ground surface. The effect of wheel-bearing type was also investigated. Six pairs of wheels and tires were tested including two sizes of each of the types designated as standard (high pressure), low pressure, and extra low pressure. The results of calculations intended to show the effect of variations in rolling friction on take-off are also presented.

  10. Male moths optimally balance take-off thoracic temperature and warm-up duration to reach a pheromone source quickly.

    PubMed

    Crespo, José G; Vickers, Neil J; Goller, Franz

    2014-12-01

    Animal activities, such as foraging and reproduction, are constrained by decisions about how to allocate energy and time efficiently. Overall, male moths invest less in reproduction than females, but they are thought to engage in a scramble competition for access to females that advertise readiness to mate by releasing sexual pheromones. However, before male moths can follow the pheromone, they often need to heat their flight muscles by shivering to produce sufficient power for sustained flight. Here, we show that Helicoverpa zea males that sense the female pheromone at high ambient temperatures take off with higher thoracic temperature, shiver for less time and warm up faster than males tested at lower ambient temperatures. These higher take-off temperatures translate into higher airspeeds, underscoring the importance of thoracic temperature for flight performance. Furthermore, shorter combined duration for warm-up and pheromone-mediated optomotor anemotaxis is consistent with the idea that males engage in scramble competition for access to females in nature. Our results strongly suggest that male moths minimize the time between perceiving the female's pheromone signal and arriving at the source by optimizing thermoregulatory behaviour and temperature-dependent flight performance in accordance with ambient temperature conditions. Our finding that moths engage in a trade-off between rapid flight initiation and suboptimal flight performance suggests a sensorimotor control mechanism that involves a complex interaction with the thermal environment. PMID:25386029

  11. Interaction of the elytra and hind wing of a rhinoceros beetle (Trypoxylus dichotomus) during a take-off mode

    NASA Astrophysics Data System (ADS)

    Oh, Seungyoung; Oh, Sehyeong; Choi, Haecheon; Lee, Boogeon; Park, Hyungmin; Kim, Sun-Tae

    2015-11-01

    The elytra are a pair of hardened wings that cover the abdomen of a beetle to protect beetle's hind wings. During the take-off, these elytra open and flap in phase with the hind wings. We investigate the effect of the elytra flapping on beetle's aerodynamic performance. Numerical simulations are performed at Re=10,000 (based on the wingtip mean velocity and mean chord length of the hind wing) using an immersed boundary method. The simulations are focused on a take-off, and the wing kinematics used is directly obtained from the experimental observations using high speed cameras. The simulation result shows three-dimensional vortical structures generated by the hind wing of the beetle and their interaction with the elytra. The presence of elytra has a negative effect on the lift generation by the hind wings, but the lift force on the elytra themselves is negligible. Further discussions on the elytra - hind wing interaction will be provided during the presentation. Supported by UD130070ID.

  12. Male moths optimally balance take-off thoracic temperature and warm-up duration to reach a pheromone source quickly

    PubMed Central

    Crespo, José G.; Vickers, Neil J.; Goller, Franz

    2014-01-01

    Animal activities, such as foraging and reproduction, are constrained by decisions about how to allocate energy and time efficiently. Overall, male moths invest less in reproduction than females, but they are thought to engage in a scramble competition for access to females that advertise readiness to mate by releasing sexual pheromones. However, before male moths can follow the pheromone, they often need to heat their flight muscles by shivering to produce sufficient power for sustained flight. Here, we show that Helicoverpa zea males that sense the female pheromone at high ambient temperatures take off with higher thoracic temperature, shiver for less time and warm up faster than males tested at lower ambient temperatures. These higher take-off temperatures translate into higher airspeeds, underscoring the importance of thoracic temperature for flight performance. Furthermore, shorter combined duration for warm-up and pheromone-mediated optomotor anemotaxis is consistent with the idea that males engage in scramble competition for access to females in nature. Our results strongly suggest that male moths minimize the time between perceiving the female's pheromone signal and arriving at the source by optimizing thermoregulatory behaviour and temperature-dependent flight performance in accordance with ambient temperature conditions. Our finding that moths engage in a trade-off between rapid flight initiation and suboptimal flight performance suggests a sensorimotor control mechanism that involves a complex interaction with the thermal environment. PMID:25386029

  13. Take-off Stability Characteristics of a 1/13-scale Model of the Consolidated Vultee Skate 7 Seaplane (TED No. NACA DE 338)

    NASA Technical Reports Server (NTRS)

    McKann, Robert; Coffee, Claude W.; Abrabian, Donald D.

    1949-01-01

    The take-off stability characteristics of a Consolidated Vultee Aircraft Corporation Skate 7 seaplane were determined in the Langley tank no. 2. Trim limits of stability, trim tracks, and elevator limits of stability are presented.

  14. Excepting Myotis capaccinii, the wings' contribution to take-off performance does not correlate with foraging ecology in six species of insectivorous bat.

    PubMed

    Gardiner, James D; Altringham, John D; Papadatou, Elena; Nudds, Robert L

    2014-01-01

    Take-off in bats is separated into two distinct phases: an initial jump and a subsequent wing powered acceleration. Here, using footage from a high-speed camera, the first comparative study of the performance during the wing induced phase of take-off in six insectivorous bat species is described. Despite distinct differences in foraging strategy, the mass specific power generated by the bats during wing induced take-off did not differ between species, with the exception of Myotis capaccinii. This suggests that differences in take-off performance may only be evident in bats that exhibit particularly unusual foraging strategies, such as the trawling behaviour of M. capaccinii - with differences in the remaining species only manifesting in subtler aspects of flight performance such as agility or manoeuvrability. The poorer take-off performance of M. capaccinii could be related to either a reduction in wing-stroke amplitude to stop the wings hitting the water's surface during foraging or perhaps an effect of having very large feet. No scaling relationship between body mass and mass-specific take-off power was found, which supports earlier research on birds and insects, suggesting that the mass-specific muscle power available for flight is broadly similar across a large range of body sizes and species. PMID:25326512

  15. Excepting Myotis capaccinii, the wings' contribution to take-off performance does not correlate with foraging ecology in six species of insectivorous bat

    PubMed Central

    Gardiner, James D.; Altringham, John D.; Papadatou, Elena; Nudds, Robert L.

    2014-01-01

    ABSTRACT Take-off in bats is separated into two distinct phases: an initial jump and a subsequent wing powered acceleration. Here, using footage from a high-speed camera, the first comparative study of the performance during the wing induced phase of take-off in six insectivorous bat species is described. Despite distinct differences in foraging strategy, the mass specific power generated by the bats during wing induced take-off did not differ between species, with the exception of Myotis capaccinii. This suggests that differences in take-off performance may only be evident in bats that exhibit particularly unusual foraging strategies, such as the trawling behaviour of M. capaccinii – with differences in the remaining species only manifesting in subtler aspects of flight performance such as agility or manoeuvrability. The poorer take-off performance of M. capaccinii could be related to either a reduction in wing-stroke amplitude to stop the wings hitting the water's surface during foraging or perhaps an effect of having very large feet. No scaling relationship between body mass and mass-specific take-off power was found, which supports earlier research on birds and insects, suggesting that the mass-specific muscle power available for flight is broadly similar across a large range of body sizes and species. PMID:25326512

  16. Design of a hydraulic power take-off system for the wave energy device with an inverse pendulum

    NASA Astrophysics Data System (ADS)

    Zhang, Da-hai; Li, Wei; Zhao, Hai-tao; Bao, Jing-wei; Lin, Yong-gang

    2014-04-01

    This paper describes a dual-stroke acting hydraulic power take-off (PTO) system employed in the wave energy converter (WEC) with an inverse pendulum. The hydraulic PTO converts slow irregular reciprocating wave motions to relatively smooth, fast rotation of an electrical generator. The design of the hydraulic PTO system and its control are critical to maximize the generated power. A time domain simulation study and the laboratory experiment of the full-scale beach test are presented. The results of the simulation and laboratory experiments including their comparison at full-scale are also presented, which have validated the rationality of the design and the reliability of some key components of the prototype of the WEC with an inverse pendulum with the dual-stroke acting hydraulic PTO system.

  17. Marine Hydrokinetic Turbine Power-Take-Off Design for Optimal Performance and Low Impact on Cost-of-Energy: Preprint

    SciTech Connect

    Beam, M.; Kline, B.; Elbing, B.; Straka, W.; Fontaine, A.; Lawson, M.; Li, Y.; Thresher, R.; Previsic, M.

    2013-02-01

    Marine hydrokinetic devices are becoming a popular method for generating marine renewable energy worldwide. These devices generate electricity by converting the kinetic energy of moving water, wave motion or currents, into electrical energy through the use of a power-take-off (PTO) system. Most PTO systems incorporate a mechanical or hydraulic drivetrain, power generator, and electric control/conditioning system to deliver the generated electric power to the grid at the required state. Like wind turbine applications, the PTO system must be designed for high reliability, good efficiency, and long service life with reasonable maintenance requirements, low cost, and an appropriate mechanical design for anticipated applied steady and unsteady loads. The ultimate goal of a PTO design is high efficiency and low maintenance and cost, with a low impact on the device cost-of-energy (CoE).

  18. Marine Hydrokinetic Turbine Power-Take-Off Design for Optimal Performance and Low Impact on Cost-of-Energy: Preprint

    SciTech Connect

    Beam, M.; Kline, B.; Elbing, B.; Straka, W.; Fontaine, A.; Lawson, M.; Li, Y.; Thresher, R.; Previsic, M.

    2012-04-01

    Marine hydrokinetic devices are becoming a popular method for generating marine renewable energy worldwide. These devices generate electricity by converting the kinetic energy of moving water, wave motion or currents, into electrical energy through the use of a Power-Take-Off (PTO) system. Most PTO systems incorporate a mechanical or hydraulic drive train, power generator and electric control/conditioning system to deliver the generated electric power to the grid at the required state. Like wind turbine applications, the PTO system must be designed for high reliability, good efficiency, and long service life with reasonable maintenance requirements, low cost and an appropriate mechanical design for anticipated applied steady and unsteady loads. The ultimate goal of a PTO design is high efficiency, low maintenance and cost with a low impact on the device Cost-of-Energy (CoE).

  19. An evaluation of composite propulsion for single-stage-to-orbit vehicles designed for horizontal take-off

    NASA Technical Reports Server (NTRS)

    Martin, J. A.

    1977-01-01

    Composite propulsion was analyzed for single-stage-to-orbit vehicles designed for horizontal take-off. Trajectory, geometric, and mass analyses were performed to establish the orbital payload capability of six engines. The results indicated that none of the engines performed adequately to deliver payloads to orbit as analyzed. The single-stage turbine and oxidizer-rich gas generator resulted in a low engine specific impulse, and the performance increment of the ejector subsystem was less than that of a separate rocket system with a high combustion pressure. There was a benefit from incorporating a fan into the engine, and removal of the fan from the airstream during the ramjet mode increased the orbital payload capability.

  20. Validation of a Flexible Aircraft TakeOff and Landing Analysis /FATOLA/ computer program using flight landing data

    NASA Technical Reports Server (NTRS)

    Carden, H. D.; Mcgehee, J. R.

    1977-01-01

    A multiple-degree-of-freedom takeoff and landing analysis, Flexible Aircraft TakeOff and Landing Analysis computer program (FATOLA), was used to predict the landing behavior of a rigid-body X-24B reentry research vehicle and of a flexible-body modified-delta-wing supersonic YF-12 research aircraft. The analytical predictions were compared with flight test data for both research vehicles. Predicted time histories of vehicle motion and attitude, landing-gear strut stroke, and axial force transmitted from the landing gear to the airframe during the landing impact and rollout compared well with the actual time histories. Based on the comparisons presented, the versatility and validity of the FATOLA program for predicting landing dynamics of aircraft has been demonstrated.

  1. Estimation of the Basic Reproductive Ratio for Dengue Fever at the Take-Off Period of Dengue Infection

    PubMed Central

    Jafaruddin; Indratno, Sapto W.; Nuraini, Nuning; Supriatna, Asep K.; Soewono, Edy

    2015-01-01

    Estimating the basic reproductive ratio ℛ0 of dengue fever has continued to be an ever-increasing challenge among epidemiologists. In this paper we propose two different constructions to estimate ℛ0 which is derived from a dynamical system of host-vector dengue transmission model. The construction is based on the original assumption that in the early states of an epidemic the infected human compartment increases exponentially at the same rate as the infected mosquito compartment (previous work). In the first proposed construction, we modify previous works by assuming that the rates of infection for mosquito and human compartments might be different. In the second construction, we add an improvement by including more realistic conditions in which the dynamics of an infected human compartments are intervened by the dynamics of an infected mosquito compartment, and vice versa. We apply our construction to the real dengue epidemic data from SB Hospital, Bandung, Indonesia, during the period of outbreak Nov. 25, 2008–Dec. 2012. We also propose two scenarios to determine the take-off rate of infection at the beginning of a dengue epidemic for construction of the estimates of ℛ0: scenario I from equation of new cases of dengue with respect to time (daily) and scenario II from equation of new cases of dengue with respect to cumulative number of new cases of dengue. The results show that our first construction of ℛ0 accommodates the take-off rate differences between mosquitoes and humans. Our second construction of the ℛ0 estimation takes into account the presence of infective mosquitoes in the early growth rate of infective humans and vice versa. We conclude that the second approach is more realistic, compared with our first approach and the previous work. PMID:26413140

  2. Estimation of the Basic Reproductive Ratio for Dengue Fever at the Take-Off Period of Dengue Infection.

    PubMed

    Jafaruddin; Indratno, Sapto W; Nuraini, Nuning; Supriatna, Asep K; Soewono, Edy

    2015-01-01

    Estimating the basic reproductive ratio ℛ 0 of dengue fever has continued to be an ever-increasing challenge among epidemiologists. In this paper we propose two different constructions to estimate ℛ 0 which is derived from a dynamical system of host-vector dengue transmission model. The construction is based on the original assumption that in the early states of an epidemic the infected human compartment increases exponentially at the same rate as the infected mosquito compartment (previous work). In the first proposed construction, we modify previous works by assuming that the rates of infection for mosquito and human compartments might be different. In the second construction, we add an improvement by including more realistic conditions in which the dynamics of an infected human compartments are intervened by the dynamics of an infected mosquito compartment, and vice versa. We apply our construction to the real dengue epidemic data from SB Hospital, Bandung, Indonesia, during the period of outbreak Nov. 25, 2008-Dec. 2012. We also propose two scenarios to determine the take-off rate of infection at the beginning of a dengue epidemic for construction of the estimates of ℛ 0: scenario I from equation of new cases of dengue with respect to time (daily) and scenario II from equation of new cases of dengue with respect to cumulative number of new cases of dengue. The results show that our first construction of ℛ 0 accommodates the take-off rate differences between mosquitoes and humans. Our second construction of the ℛ 0 estimation takes into account the presence of infective mosquitoes in the early growth rate of infective humans and vice versa. We conclude that the second approach is more realistic, compared with our first approach and the previous work. PMID:26413140

  3. Plasma jet takes off.

    PubMed Central

    Frazer, L

    1999-01-01

    Thanks to a series of joint research projects by Los Alamos National Laboratory, Beta Squared of Allen, Texas, and the University of California at Los Angeles, there is now a more environmentally sound method for cleaning semiconductor chips that may also be effective in cleaning up chemical, bacterial, and nuclear contaminants. The Atmospheric Pressure Plasma Jet uses a type of ionized gas called plasma to clean up contaminants by binding to them and lifting them away. In contrast to the corrosive acids and chemical solvents traditionally used to clean semiconductor chips, the jet oxidizes contaminants, producing only benign gaseous by-products such as oxygen and carbon dioxide. The new technology is also easy to transport, cleans thoroughly and quickly, and presents no hazards to its operators. PMID:10417375

  4. GPM Takes Off

    NASA Video Gallery

    An international satellite that will set a new standard for global precipitation measurements from space has completed a 7,300-mile journey from the United States to Japan, where it now will underg...

  5. Determining postural stability

    NASA Technical Reports Server (NTRS)

    Lieberman, Erez (Inventor); Forth, Katharine E. (Inventor); Paloski, William H. (Inventor)

    2011-01-01

    A method for determining postural stability of a person can include acquiring a plurality of pressure data points over a period of time from at least one pressure sensor. The method can also include the step of identifying a postural state for each pressure data point to generate a plurality of postural states. The method can include the step of determining a postural state of the person at a point in time based on at least the plurality of postural states.

  6. Effect of Ground Proximity on Aerodynamic Characteristics of Two Horizontal-Attitude Jet Vertical-Take-Off-and-Landing Airplane Models

    NASA Technical Reports Server (NTRS)

    Newsom, William A., Jr.

    1960-01-01

    An investigation has been made to study the effect of ground proximity on the aerodynamic characteristics of two jet vertical-take-off-and-landing airplane models in which the fuselage remains in a horizontal attitude for the take-off and landing. The first model (called the tilt-wing model) had a tilting wing-engine assembly which was set at 90 deg incidence for the take-off and landing. The second model, called the deflected-jet model) had a cascade of retractable turning vanes to deflect the exhaust of the horizontally mounted jet engines downward for vertical take-off and landing while the entire model remained in a horizontal attitude. With the models at various heights above the ground in the take-off and landing configuration, the lift, drag, and pitching moment were measured and tuft surveys were made to determine the flow field caused by the jet exhaust. The tilt-wing model experienced a loss of lift of less than 3 percent near the ground. The deflected-jet model, however, suffered losses in lift as high as 45 percent near the ground because of a low pressure region under the model caused by the entrainment of air by the jet exhaust as it spread out along the ground. This loss in lift for the deflected-jet configuration could probably be reduced to less than 5 percent by the use of a longer landing gear and a high wing location.

  7. Aerial Explorers

    NASA Technical Reports Server (NTRS)

    Young, Larry A.; Pisanich, Greg; Ippolito, Corey

    2005-01-01

    This paper presents recent results from a mission architecture study of planetary aerial explorers. In this study, several mission scenarios were developed in simulation and evaluated on success in meeting mission goals. This aerial explorer mission architecture study is unique in comparison with previous Mars airplane research activities. The study examines how aerial vehicles can find and gain access to otherwise inaccessible terrain features of interest. The aerial explorer also engages in a high-level of (indirect) surface interaction, despite not typically being able to takeoff and land or to engage in multiple flights/sorties. To achieve this goal, a new mission paradigm is proposed: aerial explorers should be considered as an additional element in the overall Entry, Descent, Landing System (EDLS) process. Further, aerial vehicles should be considered primarily as carrier/utility platforms whose purpose is to deliver air-deployed sensors and robotic devices, or symbiotes, to those high-value terrain features of interest.

  8. Structural Sizing of a Horizontal Take-Off Launch Vehicle with an Air Collection and Enrichment System

    NASA Technical Reports Server (NTRS)

    McCurdy, David R.; Roche, Joseph M.

    2004-01-01

    In support of NASA's Next Generation Launch Technology (NGLT) program, the Andrews Gryphon booster was studied. The Andrews Gryphon concept is a horizontal lift-off, two-stage-to-orbit, reusable launch vehicle that uses an air collection and enrichment system (ACES). The purpose of the ACES is to collect atmospheric oxygen during a subsonic flight loiter phase and cool it to cryogenic temperature, ultimately resulting in a reduced initial take-off weight To study the performance and size of an air-collection based booster, an initial airplane like shape was established as a baseline and modeled in a vehicle sizing code. The code, SIZER, contains a general series of volume, surface area, and fuel fraction relationships that tie engine and ACES performance with propellant requirements and volumetric constraints in order to establish vehicle closure for the given mission. A key element of system level weight optimization is the use of the SIZER program that provides rapid convergence and a great deal of flexibility for different tank architectures and material suites in order to study their impact on gross lift-off weight. This paper discusses important elements of the sizing code architecture followed by highlights of the baseline booster study.

  9. Short Field Take-Off and Landing Performance as an Enabling Technology for a Greener, More Efficient Airspace System

    NASA Technical Reports Server (NTRS)

    Hange, Craig E.

    2009-01-01

    The Cruise Efficient Short Take-Off and Landing (CESTOL) aircraft and Civil Tiltrotor (CTR) are two examples of powered-lift aircraft concepts that are of interest to NASA. These concepts will be able to utilize the shorter unused or underutilized runways and corresponding airspace at the crowded hub airports and many unused airfields and airspace that currently exist in other expanding urban areas providing additional capacity to the airspace system and reductions in congestion and delays seen in the current system. By treating the use of CESTOL and CTR as critical components that supplement other green aircraft to be used in the overall airspace system, the efficiency and improvements gained by the entire system will offset the potential increased fuel usage and emissions that may be a result of providing short field capability to the powered-lift aircraft. My presentation will address how NASA and the aerospace industry may identify, analysis, and finally implement these powered-lift aircraft into the airspace system and improve the capacity and reduce delay, while obtaining an overall reduction in noise, fuel usage, and emissions.

  10. Take-off and landing kinetics of a free-ranging gliding mammal, the Malayan colugo (Galeopterus variegatus)

    PubMed Central

    Byrnes, Greg; Lim, Norman T.-L; Spence, Andrew J

    2008-01-01

    Arboreal animals negotiate a highly three-dimensional world that is discontinuous on many spatial scales. As the scale of substrate discontinuity increases, many arboreal animals rely on leaping or gliding locomotion between distant supports. In order to successfully move through their habitat, gliding animals must actively modulate both propulsive and aerodynamic forces. Here we examined the take-off and landing kinetics of a free-ranging gliding mammal, the Malayan colugo (Galeopterus variegatus) using a custom-designed three-dimensional accelerometry system. We found that colugos increase the propulsive impulse to affect longer glides. However, we also found that landing forces are negatively associated with glide distance. Landing forces decrease rapidly as glide distance increases from the shortest glides, then level off, suggesting that the ability to reorient the aerodynamic forces prior to landing is an important mechanism to reduce velocity and thus landing forces. This ability to substantially alter the aerodynamic forces acting on the patagial wing in order to reorient the body is a key to the transition between leaping and gliding and allows gliding mammals to travel long distances between trees with reduced risk of injury. Longer glides may increase the access to distributed resources and reduce the exposure to predators in the canopy or on the forest floor. PMID:18252673

  11. Exercise and Posture

    MedlinePlus

    ... Info For Teens Message Boards & Forums Donate Shop Exercise & Posture About Spondylitis / Exercise & Posture Overview For The ... Diet Blood Work and Spondylitis Spondylitis Awareness Month Exercise Exercise is an integral part of any spondylitis ...

  12. Vertical Jump Height is more Strongly Associated with Velocity and Work Performed Prior to Take-off

    NASA Technical Reports Server (NTRS)

    Bentley, J. R.; Loehr, J. A.; DeWitt, J. K.; Lee, S. M. C.; English, K. L.; Nash, R. E.; Leach, M. A.; Hagan, R. D.

    2008-01-01

    Vertical jump (VJ) height is commonly used as a measure of athletic capability in strength and power sports. Although VJ has been shown to be a predictor of athletic performance, it is not clear which kinetic ground reaction force (GRF) variables, such as peak force (PF), peak power (PP), peak velocity (PV), total work (TW) or impulse (Imp) are the best correlates. To determine which kinetic variables (PF, PP, PV, TW, and Imp) best correlate with VJ height. Twenty subjects (14 males, 6 females) performed three maximal countermovement VJs on a force platform (Advanced Mechanical Technology, Inc., Watertown, MA, USA). VJ jump height was calculated as the difference between standing reach and the highest reach point measured using a Vertec. PF, PP, PV, TW, and Imp were calculated using the vertical GRF data sampled at 1000 Hz from the lowest point in the countermovement through the concentric portion until take-off. GRF data were normalized to body mass measured using a standard scale (Detecto, Webb City, MO, USA). Correlation coefficients were computed between each GRF variable and VJ height using a Pearson correlation. VJ height (43.4 plus or minus 9.1 cm) was significantly correlated (p less than 0.001) with PF (998 plus or minus 321 N; r=0.51), PP (1997 plus or minus 772 W; r=0.69), PV (2.66 plus or minus 0.40 m (raised dot) s(sup -1); r=0.85), TW (259 plus or minus 93.0 kJ; r=0.82), and Imp (204 plus or minus 51.1 N(raised dot)s; r=0.67). Although all variables were correlated to VJ height, PV and TW were more strongly correlated to VJ height than PF, PP, and Imp. Therefore, since TW is equal to force times displacement, the relative displacement of the center of mass along with the forces applied during the upward movement of the jump are critical determinants of VJ height. PV and TW are key determinants of VJ height, and therefore successful training programs to increase VJ height should focus on rapid movement (PV) and TW by increasing power over time rather

  13. Semiempirical Procedure for Estimating Lift and Drag Characteristics of Propeller-Wing-Flap Configurations for Vertical-and Short-Take-Off-and-Landing Airplanes

    NASA Technical Reports Server (NTRS)

    Kuhn, Richard E.

    1959-01-01

    The analysis presented uses the momentum theory as a starting point in developing semiempirical expressions for calculating the effect of propeller thrust and slipstream on the lift and drag characteristics of wing-flap configurations that would be suitable for vertical-take-off-and-landing (VTOL) and short-take-off-and-landing (STOL) airplanes. The method uses power-off forward-speed information and measured slipstream deflection data at zero forward speed to provide a basis for estimating the lift and drag at combined forward speed and power-on conditions. A correlation of slipstream deflection data is also included. The procedure is applicable only in the unstalled flight regime; nevertheless, it should be useful in preliminary design estimates of the performance that may be expected of VTOL and STOL airplanes.

  14. Effects of the kinematic viscosity and surface tension on the bubble take-off period in a catalase-hydrogen peroxide system.

    PubMed

    Sasaki, Satoshi; Iida, Yoshinori

    2009-06-01

    The effect of kinematic viscosity and surface tension of the solution was investigated by adding catalase, glucose oxidase, or glucose on the bubble movement in a catalase-hydrogen peroxide system. The kinematic viscosity was measured using a Cannon-Fenske kinematic viscometer. The surface tension of the solution was measured by the Wilhelmy method using a self-made apparatus. The effects of the hole diameter/cell wall thickness, catalase concentration, glucose concentration, and glucose oxidase concentration on the kinematic viscosity, surface tension, and bubble take-off period were investigated. With our system, the effects of the changes in the solution materiality on the bubble take-off period were proven to be very small in comparison to the change in the oxygen-producing rate. PMID:19250805

  15. Exploratory investigation of the effectiveness of biplane wings with large-chord double slotted flaps in redirecting a propeller slipstream downward for vertical take-off

    NASA Technical Reports Server (NTRS)

    Kirby, Robert H

    1956-01-01

    Results are presented from static-force tests on biplane wings with large-chord double slotted flaps which turn the slipstream of a single counter rotating propeller downward for vertical take-off. The investigation provided information on the effect of chord length, flap deflection, propeller position, end plates, fuselage, and ground proximity on the efficiency of the wing system in turning the propeller slipstream.

  16. Transition-flight Tests of a Model of a Low-wing Transport Vertical-take-off Airplane with Tilting Wing and Propellers

    NASA Technical Reports Server (NTRS)

    Lovell, Powell M , Jr; Parlett, Lysle P

    1956-01-01

    An investigation of the stability and control of a low-wing four-engine transport vertical-take-off airplane during the transition from hovering to normal forward flight has been conducted with a remotely controlled free-flight model. The model had four propellers distributed along the wing with the thrust axes in the wing-chord plane. The wing could be rotated to 90 degrees incidence so that the propeller thrust axes were vertical for hovering flight.

  17. Intra-specific variation in wing morphology and its impact on take-off performance in blue tits (Cyanistes caeruleus) during escape flights

    PubMed Central

    McFarlane, Laura; Altringham, John D.; Askew, Graham N.

    2016-01-01

    ABSTRACT Diurnal and seasonal increases in body mass and seasonal reductions in wing area may compromise a bird's ability to escape, as less of the power available from the flight muscles can be used to accelerate and elevate the animal's centre of mass. Here, we investigated the effects of intra-specific variation in wing morphology on escape take-off performance in blue tits (Cyanistes caeruleus). Flights were recorded using synchronised high-speed video cameras and take-off performance was quantified as the sum of the rates of change of the kinetic and potential energies of the centre of mass. Individuals with a lower wing loading, WL (WL=body weight/wing area) had higher escape take-off performance, consistent with the increase in lift production expected from relatively larger wings. Unexpectedly, it was found that the total power available from the flight muscles (estimated using an aerodynamic analysis) was inversely related to WL. This could simply be because birds with a higher WL have relatively smaller flight muscles. Alternatively or additionally, variation in the aerodynamic load on the wing resulting from differences in wing morphology will affect the mechanical performance of the flight muscles via effects on the muscle's length trajectory. Consistent with this hypothesis is the observation that wing beat frequency and relative downstroke duration increase with decreasing WL; both are factors that are expected to increase muscle power output. Understanding how wing morphology influences take-off performance gives insight into the potential risks associated with feather loss and seasonal and diurnal fluctuations in body mass. PMID:26994175

  18. Intra-specific variation in wing morphology and its impact on take-off performance in blue tits (Cyanistes caeruleus) during escape flights.

    PubMed

    McFarlane, Laura; Altringham, John D; Askew, Graham N

    2016-05-01

    Diurnal and seasonal increases in body mass and seasonal reductions in wing area may compromise a bird's ability to escape, as less of the power available from the flight muscles can be used to accelerate and elevate the animal's centre of mass. Here, we investigated the effects of intra-specific variation in wing morphology on escape take-off performance in blue tits (Cyanistes caeruleus). Flights were recorded using synchronised high-speed video cameras and take-off performance was quantified as the sum of the rates of change of the kinetic and potential energies of the centre of mass. Individuals with a lower wing loading, WL (WL=body weight/wing area) had higher escape take-off performance, consistent with the increase in lift production expected from relatively larger wings. Unexpectedly, it was found that the total power available from the flight muscles (estimated using an aerodynamic analysis) was inversely related to WL. This could simply be because birds with a higher WL have relatively smaller flight muscles. Alternatively or additionally, variation in the aerodynamic load on the wing resulting from differences in wing morphology will affect the mechanical performance of the flight muscles via effects on the muscle's length trajectory. Consistent with this hypothesis is the observation that wing beat frequency and relative downstroke duration increase with decreasing WL; both are factors that are expected to increase muscle power output. Understanding how wing morphology influences take-off performance gives insight into the potential risks associated with feather loss and seasonal and diurnal fluctuations in body mass. PMID:26994175

  19. Take-off time of the first generation of the overwintering small brown planthopper, Laodelphax striatellus in the temperate zone in East Asia.

    PubMed

    Sanada-Morimura, Sachiyo; Otuka, Akira; Matsumura, Masaya; Etoh, Tomoki; Zhu, Yeqin; Zhou, Yijun; Zhang, Gufeng

    2015-01-01

    Overseas migration of the small brown planthopper, Laodelphax striatellus (Fallén), occurs during the winter wheat harvest season in East Asia. Knowing the take-off time of emigrating L. striatellus is crucial for predicting such migrations with a simulation technique because winds, carriers of migratory insects, change continuously. Several methods were used in China and Japan from late May to early June 2012 and again in 2013 to identify the precise timing of take-off. These methods included: a tow net trap mounted to a pole at 10 m above the ground, a helicopter-towed net trap, and a canopy trap (which also had video monitoring) set over wheat plants. Laodelphax striatellus emigrated from wheat fields mainly in the early evening, before dusk. The insects also emigrated during the daytime but rarely emigrated at dawn, showing a pattern that is unlike the bimodal emigration at dusk and dawn of two other rice planthoppers, the brown planthopper, Nilaparvata lugens (Stål), and the white-backed planthopper, Sogatella furcifera (Horváth). There was no significant difference in the temporal pattern of take-off behavior between females and males of Japanese L. striatellus populations. PMID:25780936

  20. Take-Off Time of the First Generation of the Overwintering Small Brown Planthopper, Laodelphax striatellus in the Temperate Zone in East Asia

    PubMed Central

    Sanada-Morimura, Sachiyo; Otuka, Akira; Matsumura, Masaya; Etoh, Tomoki; Zhu, Yeqin; Zhou, Yijun; Zhang, Gufeng

    2015-01-01

    Overseas migration of the small brown planthopper, Laodelphax striatellus (Fallén), occurs during the winter wheat harvest season in East Asia. Knowing the take-off time of emigrating L. striatellus is crucial for predicting such migrations with a simulation technique because winds, carriers of migratory insects, change continuously. Several methods were used in China and Japan from late May to early June 2012 and again in 2013 to identify the precise timing of take-off. These methods included: a tow net trap mounted to a pole at 10 m above the ground, a helicopter-towed net trap, and a canopy trap (which also had video monitoring) set over wheat plants. Laodelphax striatellus emigrated from wheat fields mainly in the early evening, before dusk. The insects also emigrated during the daytime but rarely emigrated at dawn, showing a pattern that is unlike the bimodal emigration at dusk and dawn of two other rice planthoppers, the brown planthopper, Nilaparvata lugens (Stål), and the white-backed planthopper, Sogatella furcifera (Horváth). There was no significant difference in the temporal pattern of take-off behavior between females and males of Japanese L. striatellus populations. PMID:25780936

  1. Flight Investigation of the Stability and Control Characteristics of a 1/4-Scale Model of a Tilt-Wing Vertical-Take-Off-and-Landing Aircraft

    NASA Technical Reports Server (NTRS)

    Tosti, Louis P.

    1959-01-01

    An experimental investigation has been conducted to determine the dynamic stability and control characteristics of a tilt-wing vertical-take-off-and-landing aircraft with the use of a remotely controlled 1/4-scale free-flight model. The model had two propellers with hinged (flapping) blades mounted on the wing which could be tilted up to an incidence angle of nearly 90 deg for vertical take-off and landing. The investigation consisted of hovering flights in still air, vertical take-offs and landings, and slow constant-altitude transitions from hovering to forward flight. The stability and control characteristics of the model were generally satisfactory except for the following characteristics. In hovering flight, the model had an unstable pitching oscillation of relatively long period which the pilots were able to control without artificial stabilization but which could not be considered entirely satisfactory. At very low speeds and angles of wing incidence on the order of 70 deg, the model experienced large nose-up pitching moments which severely limited the allowable center-of-gravity range.

  2. Force balance in the take-off of a pierid butterfly: relative importance and timing of leg impulsion and aerodynamic forces.

    PubMed

    Bimbard, Gaëlle; Kolomenskiy, Dmitry; Bouteleux, Olivier; Casas, Jérôme; Godoy-Diana, Ramiro

    2013-09-15

    Up to now, the take-off stage has remained an elusive phase of insect flight that was relatively poorly explored compared with other maneuvers. An overall assessment of the different mechanisms involved in force production during take-off has never been explored. Focusing on the first downstroke, we have addressed this problem from a force balance perspective in butterflies taking off from the ground. In order to determine whether the sole aerodynamic wing force could explain the observed motion of the insect, we have firstly compared a simple analytical model of the wing force with the acceleration of the insect's center of mass estimated from video tracking of the wing and body motions. Secondly, wing kinematics were also used for numerical simulations of the aerodynamic flow field. Similar wing aerodynamic forces were obtained by the two methods. However, neither are sufficient, nor is the inclusion of the ground effect, to predict faithfully the body acceleration. We have to resort to the leg forces to obtain a model that best fits the data. We show that the median and hind legs display an active extension responsible for the initiation of the upward motion of the insect's body, occurring before the onset of the wing downstroke. We estimate that legs generate, at various times, an upward force that can be much larger than all other forces applied to the insect's body. The relative timing of leg and wing forces explains the large variability of trajectories observed during the maneuvers. PMID:23788714

  3. Analysis of the effects of boundary-layer control in the take-off and power-off landing performance characteristics of a liaison type of airplane

    NASA Technical Reports Server (NTRS)

    Horton, Elmer A; Loftin, Laurence K; Racisz, Stanley F; Quinn, John

    1951-01-01

    A performance analysis has been made to determine whether boundary-layer control by suction might reduce the minimum take-off and landing distances of a four-place or five-place airplane or a liaison type of airplane below those obtainable with conventional high-lift devices. The airplane was assumed to have a cruise duration of 5 hours at 60-percent power and to be operating from airstrips having a ground friction coefficient of 0.2 or a combined ground and braking coefficient of 0.4. The payload was fixed at 1500 pounds, the wing span was varied from 25 to 100 feet, the aspect ratio was varied from 5 to 15, and the power was varied from 300 to 1300 horsepower. Maximum lift coefficients of 5.0 and 2.8 were assumed for the airplanes with and without boundary-layer-control --equipment weight was included. The effects of the boundary-layer control on total take-off distance, total power-off landing distance, landing and take-off ground run, stalling speed, sinking speed, and gliding speed were determined.

  4. Social Postural Coordination

    ERIC Educational Resources Information Center

    Varlet, Manuel; Marin, Ludovic; Lagarde, Julien; Bardy, Benoit G.

    2011-01-01

    The goal of the current study was to investigate whether a visual coupling between two people can produce spontaneous interpersonal postural coordination and change their intrapersonal postural coordination involved in the control of stance. We examined the front-to-back head displacements of participants and the angular motion of their hip and…

  5. Effect of UV-Blocking Plastic Films on Take-Off and Host Plant Finding Ability of Diaphorina citri (Hemiptera: Liviidae).

    PubMed

    Miranda, M P; Dos Santos, F L; Felippe, M R; Moreno, A; Fereres, A

    2015-02-01

    The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is a major pest of citrus worldwide due to its ability to transmit the bacteria associated with huanglongbing. Vision, behavior, and performance of insect pests can be manipulated by using ultraviolet (UV)-blocking materials. Thus, the aim of our study was to evaluate how UV-blocking plastic films may affect the take-off and host plant finding ability of D. citri. To assess the effect of a UV-deficient environment on take-off, adult psyllids were released from a vial inside a screenhouse covered by a UV-blocking or standard (control) film and the number of insects remaining on each vial under each treatment was counted at different time intervals. Moreover, to assess the ability of D. citri to find citrus plants under a UV-deficient environment, two independent no-choice host plant finding assays with different plant arrangements were conducted. In each treatment, the number of psyllids per plant at different time intervals was counted. Both D. citri take-off and host plant finding ability was clearly disrupted under a UV-deficient environment. The number of psyllids remaining in the vials was significantly higher under UV-blocking than standard film in all periods recorded. Furthermore, psyllids were present in significantly higher number on citrus plants under standard film than under UV-blocking film in all of the periods assessed and experiments conducted. Our results showed that UV-blocking materials could become a valuable strategy for integrated management of D. citri and huanglongbing in citrus grown in enclosed environments. PMID:26470126

  6. Estimation of Joint Forces and Moments for the In-Run and Take-Off in Ski Jumping Based on Measurements with Wearable Inertial Sensors

    PubMed Central

    Logar, Grega; Munih, Marko

    2015-01-01

    This study uses inertial sensors to measure ski jumper kinematics and joint dynamics, which was until now only a part of simulation studies. For subsequent calculation of dynamics in the joints, a link-segment model was developed. The model relies on the recursive Newton–Euler inverse dynamics. This approach allowed the calculation of the ground reaction force at take-off. For the model validation, four ski jumpers from the National Nordic center performed a simulated jump in a laboratory environment on a force platform; in total, 20 jumps were recorded. The results fit well to the reference system, presenting small errors in the mean and standard deviation and small root-mean-square errors. The error is under 12% of the reference value. For field tests, six jumpers participated in the study; in total, 28 jumps were recorded. All of the measured forces and moments were within the range of prior simulated studies. The proposed system was able to indirectly provide the values of forces and moments in the joints of the ski-jumpers' body segments, as well as the ground reaction force during the in-run and take-off phases in comparison to the force platform installed on the table. Kinematics assessment and estimation of dynamics parameters can be applied to jumps from any ski jumping hill. PMID:25985167

  7. Estimation of joint forces and moments for the in-run and take-off in ski jumping based on measurements with wearable inertial sensors.

    PubMed

    Logar, Grega; Munih, Marko

    2015-01-01

    This study uses inertial sensors to measure ski jumper kinematics and joint dynamics, which was until now only a part of simulation studies. For subsequent calculation of dynamics in the joints, a link-segment model was developed. The model relies on the recursive Newton-Euler inverse dynamics. This approach allowed the calculation of the ground reaction force at take-off. For the model validation, four ski jumpers from the National Nordic center performed a simulated jump in a laboratory environment on a force platform; in total, 20 jumps were recorded. The results fit well to the reference system, presenting small errors in the mean and standard deviation and small root-mean-square errors. The error is under 12% of the reference value. For field tests, six jumpers participated in the study; in total, 28 jumps were recorded. All of the measured forces and moments were within the range of prior simulated studies. The proposed system was able to indirectly provide the values of forces and moments in the joints of the ski-jumpers' body segments, as well as the ground reaction force during the in-run and take-off phases in comparison to the force platform installed on the table. Kinematics assessment and estimation of dynamics parameters can be applied to jumps from any ski jumping hill. PMID:25985167

  8. The course correction implementation of the inertial navigation system based on the information from the aircraft satellite navigation system before take-off

    NASA Astrophysics Data System (ADS)

    Markelov, V.; Shukalov, A.; Zharinov, I.; Kostishin, M.; Kniga, I.

    2016-04-01

    The use of the correction course option before aircraft take-off after inertial navigation system (INS) inaccurate alignment based on the platform attitude-and-heading reference system in azimuth is considered in the paper. A course correction is performed based on the track angle defined by the information received from the satellite navigation system (SNS). The course correction includes a calculated track error definition during ground taxiing along straight sections before take-off with its input in the onboard digital computational system like amendment for using in the current flight. The track error calculation is performed by the statistical evaluation of the track angle comparison defined by the SNS information with the current course measured by INS for a given number of measurements on the realizable time interval. The course correction testing results and recommendation application are given in the paper. The course correction based on the information from SNS can be used for improving accuracy characteristics for determining an aircraft path after making accelerated INS preparation concerning inaccurate initial azimuth alignment.

  9. 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.

  10. 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.

  11. Wind-Tunnel Investigation of Subsonic Longitudinal Aerodynamic Characteristics of a Tiltable-Wing Vertical-Take-Off-and-Landing Supersonic Bomber Configuration Including Turbojet Power Effects

    NASA Technical Reports Server (NTRS)

    Thompson, Robert F.; Vogler, Raymond D.; Moseley, William C., Jr.

    1959-01-01

    Jet-powered model tests were made to determine the low-speed longitudinal aerodynamic characteristics of a vertical-take-off and-landing supersonic bomber configuration. The configuration has an unique engine-wing arrangement wherein six large turbojet engines (three on each side of the fuselage) are buried in a low-aspect-ratio wing which is tilted into the vertical plane for take-off. An essentially two-dimensional variable inlet, spanning the leading edge of each wing semispan, provides air for the engines. Jet flow conditions were simulated for a range of military (nonafterburner) and afterburner turbojet-powered flight at subsonic speeds. Three horizontal tails were tested at a station down-stream of the jet exit and at three heights above the jet axes. A semi-span model was used and test parameters covered wing-fuselage incidence angles from 0 deg to 15 deg, wing angles of attack from -4 deg to 36 deg, a variable range of horizontal-tail incidence angles, and some variations in power simulation conditions. Results show that, with all horizontal tails tested, there were large variations in static stability throughout the lift range. When the wing and fuselage were alined, the model was statically stable throughout the test range only with the largest tail tested (tail span of 1.25 wing span) and only when the tail was located in the low test position which placed the tail nearest to the undeflected jet. For transition flight conditions, none of the tail configurations provided satisfactory longitudinal stability or trim throughout the lift range. Jet flow was destabilizing for most of the test conditions, and varying the jet-exit flow conditions at a constant thrust coefficient had little effect on the stability of this model. Wing leading-edge simulation had some important effects on the longitudinal aerodynamic characteristics.

  12. Autoimmune Basis for Postural Tachycardia Syndrome

    ClinicalTrials.gov

    2016-03-30

    Postural Orthostatic Tachycardia Syndrome; Postural Tachycardia Syndrome; Tachycardia; Arrhythmias, Cardiac; Autonomic Nervous System Diseases; Orthostatic Intolerance; Cardiovascular Diseases; Primary Dysautonomias

  13. Tips to Maintain Good Posture

    MedlinePlus

    ... Pain and Chiropractic Posture Spinal Health Winter Activities Backpack Safety Kids and Sports Exercising Outdoors with Baby ... Pain and Chiropractic Posture Spinal Health Winter Activities Backpack Safety Kids and Sports Exercising Outdoors with Baby ...

  14. Postural Orthostatic Tachycardia Syndrome

    PubMed Central

    2014-01-01

    The postural orthostatic tachycardia syndrome is a disease characterized by excessively increased heart rate during orthostatic challenge associated with symptoms of orthostatic intolerance including dizziness, exercise intolerance, headache, fatigue, memory problems, nausea, blurred vision, pallor, and sweating, which improve with recumbence. Postural orthostatic tachycardia syndrome patients may present with a multitude of additional symptoms that are attributable to vascular vasoconstriction. Observed signs and symptoms in a patient with postural orthostatic tachycardia syndrome include tachycardia at rest, exaggerated heart rate increase with upright position and exercise, crushing chest pain, tremor, syncope, loss of vision, confusion, migraines, fatigue, heat intolerance, parasthesia, dysesthesia, allodynia, altered traditional senses, and thermoregulatory abnormalities. There are a number of possible dermatological manifestations of postural orthostatic tachycardia syndrome easily explained by its recently discovered pathophysiology. The author reports the case of a 22-year-old woman with moderate-to-severe postural orthostatic tachycardia syndrome with numerous dermatological manifestations attributable to the disease process. The cutaneous manifestations observed in this patient are diverse and most noticeable during postural orthostatic tachycardia syndrome flares. The most distinct are evanescent, hyperemic, sharply demarcated, irregular patches on the chest and neck area that resolve upon diascopy. This distinct “evanescent hyperemia” disappears spontaneously after seconds to minutes and reappears unexpectedly. Other observed dermatological manifestations of this systemic disease include Raynaud’s phenomenon, koilonychia, onychodystrophy, madarosis, dysesthesia, allodynia, telogen effluvium, increased capillary refill time, and livedo reticularis. The treatment of this disease poses a great challenge. The author reports the unprecedented use of an

  15. European Biospheric Network Takes Off

    NASA Astrophysics Data System (ADS)

    Brovkin, Victor; Reick, Christian; van Bodegom, Peter

    2010-04-01

    Opening Symposium of the TERRABITES Network; Hamburg, Germany, 9-11 February 2010; The huge amount of recently acquired information about the functioning of the terrestrial biosphere and the ever increasing spatial resolution of Earth system models call for a new level of integrating efforts among biosphere modelers, developers of ecological theory, and data-gathering communities. Responding to this call, a new European network, Terrestrial Biosphere in the Earth System (TERRABITES), held its opening symposium in Germany. The meeting was organized jointly with another recently founded European network, Advancing the Integrated Monitoring of Trace Gas Exchange Between Biosphere and Atmosphere (ABBA). Almost 100 scientific contributions covered the latest advances in modeling ecophysiological and biogeochemical processes; analyses of model constraints set by measurements of water and carbon dioxide (CO2) fluxes, including carbon isotopes; and new perspectives in using remote sensing data for evaluation of global terrestrial biosphere models.

  16. Professional Learning Networks Taking Off

    ERIC Educational Resources Information Center

    Flanigan, Robin L.

    2012-01-01

    Busy educators who want to ask advice, offer opinions, and engage in discussions with colleagues increasingly turn to professional learning networks (PLNs)--online communities that allow the sharing of lesson plans, teaching strategies, and student work, as well as collaboration across grade levels and departments. As budget cuts limit…

  17. Posture and Movement

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Session TP3 includes short reports on: (1) Modification of Goal-Directed Arm Movements During Inflight Adaptation to Microgravity; (2) Quantitative Analysis of Motion control in Long Term Microgravity; (3) Does the Centre of Gravity Remain the Stabilised Reference during Complex Human Postural Equilibrium Tasks in Weightlessness?; and (4) Arm End-Point Trajectories Under Normal and Microgravity Environments.

  18. Stopover optimization in a long-distance migrant: the role of fuel load and nocturnal take-off time in Alaskan northern wheatears (Oenanthe oenanthe)

    PubMed Central

    2013-01-01

    Introduction In long-distance migrants, a considerably higher proportion of time and energy is allocated to stopovers rather than to flights. Stopover duration and departure decisions affect consequently subsequent flight stages and overall speed of migration. In Arctic nocturnal songbird migrants the trade-off between a relatively long migration distance and short nights available for travelling may impose a significant time pressure on migrants. Therefore, we hypothesize that Alaskan northern wheatears (Oenanthe oenanthe) use a time-minimizing migration strategy to reach their African wintering area 15,000 km away. Results We estimated the factors influencing the birds’ daily departure probability from an Arctic stopover before crossing the Bering Strait by using a Cormack-Jolly-Seber model. To identify in which direction and when migration was resumed departing birds were radio-tracked. Here we show that Alaskan northern wheatears did not behave as strict time minimizers, because their departure fuel load was unrelated to fuel deposition rate. All birds departed with more fuel load than necessary for the sea crossing. Departure probability increased with stopover duration, evening fuel load and decreasing temperature. Birds took-off towards southwest and hence, followed in general the constant magnetic and geographic course but not the alternative great circle route. Nocturnal departure times were concentrated immediately after sunset. Conclusion Although birds did not behave like time-minimizers in respect of the optimal migration strategies their surplus of fuel load clearly contradicted an energy saving strategy in terms of the minimization of overall energy cost of transport. The observed low variation in nocturnal take-off time in relation to local night length compared to similar studies in the temperate zone revealed that migrants have an innate ability to respond to changes in the external cue of night length. Likely, birds maximized their potential

  19. Hydrodynamic Investigation of the the Take-Off Characteristics of a 1/10-Scale Dynamic Model of the Convair XF2Y-1 Airplane

    NASA Technical Reports Server (NTRS)

    McBridge, Ellis E.; Fisher, Lloyd J.

    1954-01-01

    An investigation was made of the take-off characteristics of a 1/10-scale dynamic model of the Convair XF2Y-1 airplane. This airplane is a water-based, jet-propelled, delta-wing fighter incorporating a hydro-ski landing gear. Tests were made with the original configuration, with the beaching wheels removed, and with the wheels installed and fairings added in front of the wheels. Each configuration was tested at weight and balance conditions simulating 17,000 pounds gross weight with the moment due t o 7,600 pounds of thrust, 17,300 pounds gross weight with a 9,500-pound thrust condition, and 23,000 pounds gross weight with a 9,300-pound thrust condition. Constant-speed runs were made at various elevon settings and vertical ski-strut positions; and trim, rise, and resistance were measured. Accelerated runs were made with controlled elevons and scale shock struts which could be extended as desired, and the longitudinal stability and spray characteristics were observed and photographed.

  20. A qualitative analysis of power take-off driveline shields: barriers and motivators to shield use for New York State farmers.

    PubMed

    Weil, R; Mellors, P; Fiske, T; Sorensen, J A

    2014-01-01

    Machinery entanglements are one of the top three causes of death in farming. Education on the risks of unshielded power take-off (PTO) equipment does not appear to significantly alter farmers' willingness to replace missing or broken shielding. Different assessments conducted in various regions of the U.S. indicate that as many as one-third to one-half of PTOs are inadequately shielded. Qualitative research was conducted with New York farmers to identify the factors that influence the decision to replace damaged or missing PTO driveline shields. Interview topics included: knowledge of entanglement risks, decisions regarding safety in general, decisions relating to PTO driveline shielding specifically, and the barriers and motivators to replacing missing or broken PTO driveline shields. Interviews with 38 farmers revealed the following themes: (1) farmers are fully aware of PTO entanglement risk, (2) insufficient time and money are primary barriers to purchasing or replacing damaged or missing PTO driveline shields, (3) PTO driveline shield designs are problematic and have led to negative experiences with shielding, and (4) risk acceptance and alternate work strategies are preferred alternatives to replacing shields. Our findings indicate that more innovative approaches will be required to make PTO driveline shield use a viable and attractive choice for farmers. New shield designs that address the practical barriers farmers face, as well as the provision of logistical and financial assistance for shield replacement, may alter the decision environment sufficiently to make replacing PTO driveline shielding a more attractive option for farmers. PMID:24804464

  1. ADP-ribosylation factor arf6p may function as a molecular switch of new end take off in fission yeast

    SciTech Connect

    Fujita, Atsushi

    2008-02-01

    Small GTPases act as molecular switches in a wide variety of cellular processes. In fission yeast Schizosaccharomyces pombe, the directions of cell growth change from a monopolar manner to a bipolar manner, which is known as 'New End Take Off' (NETO). Here I report the identification of a gene, arf6{sup +}, encoding an ADP-ribosylation factor small GTPase, that may be essential for NETO. arf6{delta} cells completely fail to undergo NETO. arf6p localizes at both cell ends and presumptive septa in a cell-cycle dependent manner. And its polarized localization is not dependent on microtubules, actin cytoskeletons and some NETO factors (bud6p, for3p, tea1p, tea3p, and tea4p). Notably, overexpression of a fast GDP/GTP-cycling mutant of arf6p can advance the timing of NETO. These findings suggest that arf6p functions as a molecular switch for the activation of NETO in fission yeast.

  2. Postural development in rats.

    PubMed

    Lelard, T; Jamon, M; Gasc, J-P; Vidal, P-P

    2006-11-01

    Mammals adopt a limited number of postures during their day-to-day activities. These stereotyped skeletal configurations are functionally adequate and limit the number of degrees of freedom to be controlled by the central nervous system. The temporal pattern of emergence of these configurations in altricial mammals is unknown. We therefore carried out an X-ray study in unrestrained rats from birth (P0) until postnatal day 23 (P23). The X-rays showed that many of the skeletal configurations described in adult rodents were already present at birth. By contrast, limb placement changed abruptly at around P10. These skeletal configurations, observed in anesthetized pups, required the maintenance of precise motor control. On the other hand, motor control continued to mature, as shown by progressive changes in resting posture and head movements from P0 to P23. We suggest that a few innate skeletal configurations provide the necessary frames of reference for the gradual construction of an adult motor repertoire in altricial mammals, such as the rat. The apparent absence of a requirement for external sensorial cues in the maturation of this repertoire may account for the maturation of postural and motor control in utero in precocial mammals (Muir et al., 2000 for a review on the locomotor behavior of altricial and precocial animals). PMID:16814770

  3. Stand Up Straight: Posture for Singers.

    ERIC Educational Resources Information Center

    Gauthier, Delores R.

    2002-01-01

    Focuses on the importance of posture in music-making. Provides information on the importance of posture and the different types of posture stances to help students work toward better posture. Includes information on using kinesthetic experiences to help students improve their posture. (CMK)

  4. Postural stress analysis in industry.

    PubMed

    Genaidy, A M; Al-Shedi, A A; Karwowski, W

    1994-04-01

    Both observational and instrumentation-based techniques have been used to conduct postural stress analysis in industry. As observational methods are more widespread than instrumentation-based techniques and can be used as a practical tool in the workplace, this study reviews and assesses the scientific literature on observational techniques. Techniques are classified into macropostural, micropostural and postural-work activity. The basis for each classification is outlined and evaluated. Postural recording is performed either continuously or intermittently. Intermittent postural recording procedures lack the criteria for determining the optimum number of observations for low and high repetitive jobs. Research is warranted to examine the sources and magnitudes of errors associated with postural classification. Such information is required to train job analysts in the ergonomics of working postures. PMID:15676953

  5. Posture modulates implicit hand maps.

    PubMed

    Longo, Matthew R

    2015-11-01

    Several forms of somatosensation require that afferent signals be informed by stored representations of body size and shape. Recent results have revealed that position sense relies on a highly distorted body representation. Changes of internal hand posture produce plastic alterations of processing in somatosensory cortex. This study therefore investigated how such postural changes affect implicit body representations underlying position sense. Participants localised the knuckles and tips of each finger in external space in two postures: the fingers splayed (Apart posture) or pressed together (Together posture). Comparison of the relative locations of the judgments of each landmark were used to construct implicit maps of represented hand structure. Spreading the fingers apart produced increases in the implicit representation of hand size, with no apparent effect on hand shape. Thus, changes of internal hand posture produce rapid modulation of how the hand itself is represented, paralleling the known effects on somatosensory cortical processing. PMID:26117153

  6. Assessment of postural balance function.

    PubMed

    Kostiukow, Anna; Rostkowska, Elzbieta; Samborski, Włodzimierz

    2009-01-01

    Postural balance is defined as the ability to stand unassisted without falling. Examination of the patient's postural balance function is a difficult diagnostic task. Most of the balance tests used in medicine provide incomplete information on this coordination ability of the human body. The aim of this study was to review methods of assessment of the patient's postural balance function, including various tests used in medical diagnostics centers. PMID:20698188

  7. Aerial radiation surveys

    SciTech Connect

    Jobst, J.

    1980-01-01

    A recent aerial radiation survey of the surroundings of the Vitro mill in Salt Lake City shows that uranium mill tailings have been removed to many locations outside their original boundary. To date, 52 remote sites have been discovered within a 100 square kilometer aerial survey perimeter surrounding the mill; 9 of these were discovered with the recent aerial survey map. Five additional sites, also discovered by aerial survey, contained uranium ore, milling equipment, or radioactive slag. Because of the success of this survey, plans are being made to extend the aerial survey program to other parts of the Salt Lake valley where diversions of Vitro tailings are also known to exist.

  8. Smooth-Water Landing Stability and Rough-Water Landing and Take-Off Behavior of a 1/13-Scale Model of the Consolidated Vultee Skate 7 Seaplane, TED No. NACA DE 338

    NASA Technical Reports Server (NTRS)

    McKann, Robert F.; Coffee, Claude W.; Arabian, Donald D.

    1949-01-01

    A model of the Consolidated Vultee Aircraft Corporation Skate 7 seaplane was tested in Langley tank no. 2. Presented without discussion in this paper are landing stability in smooth water, maximum normal accelerations occurring during rough-water landings, and take-off behavior in waves.

  9. Postural performance of vestibular loss patients under increased postural threat.

    PubMed

    Young, Laurence R; Bernard-Demanze, Laurence; Dumitrescu, Michel; Magnan, Jacques; Borel, Liliane; Lacour, Michel

    2012-01-01

    The effects of increasing postural task difficulty on balance control was investigated in 9 compensated vestibular loss patients whose results were compared to 11 healthy adults. Subjects were tested in static (stable support) and dynamic (sinusoidal translation of the support) conditions, both at floor level and at height (62 cm above the floor), and with and without vision, to create an additional postural threat. Wavelet analysis of the center of foot pressure displacement and motion analysis of the body segments were used to evaluate the postural performance. Evaluation questionnaires were used to examine the compensation level of the patients (DHI test), their general anxiety level (SAST), fear of height (subjective scale), and workload (NASA TLX test). (Vestibular loss patients rely more on vision and spend more energy maintaining balance than controls, but they use the same postural strategy as normals in both static and dynamic conditions.) Questionnaire data all showed differences in behavior and perceptions between the controls and the patients. However, at height and without vision, a whole body strategy leading to rigid posture replaces the head stabilization strategy found for standing at floor level. The effects of height on postural control can be attributable to an increase in postural threat and attention changes resulting from modifications in perception. PMID:23000612

  10. Aerial Image Systems

    NASA Astrophysics Data System (ADS)

    Clapp, Robert E.

    1987-09-01

    Aerial images produce the best stereoscopic images of the viewed world. Despite the fact that every optic in existence produces an aerial image, few persons are aware of their existence and possible uses. Constant reference to the eye and other optical systems have produced a psychosis of design that only considers "focal planes" in the design and analysis of optical systems. All objects in the field of view of the optical device are imaged by the device as an aerial image. Use of aerial images in vision and visual display systems can provide a true stereoscopic representation of the viewed world. This paper discusses aerial image systems - their applications and designs and presents designs and design concepts that utilize aerial images to obtain superior visual displays, particularly with application to visual simulation.

  11. Seated postural hypotension.

    PubMed

    Gorelik, Oleg; Cohen, Natan

    2015-12-01

    Most studies of postural hypotension (PH) have focused on standing PH. Less is known about PH after transition from a supine to sitting position. Moreover, seated PH has not been previously reviewed in the English literature. The aim of this review was to provide current information regarding seating-induced PH. Seventeen studies were reviewed regarding prevalence, methods of evaluation, manifestations, predisposing factors, prognosis, and management of seated PH. Prevalence ranged from 8% among community-dwelling persons to 56% in elderly hospitalized patients. Dizziness and palpitations were the most frequent symptoms. Of a variety of factors that have been identified as predisposing and contributing to seated PH, aging, bed rest, and hypertension were most important. Because seated PH is a common, easily diagnosable and frequently symptomatic condition, especially in elderly inpatients, this disorder warrants attention. Moreover, seating-induced falls in blood pressure and the associated symptoms, may be largely prevented by nonpharmacologic interventions. PMID:26515671

  12. Take-Off and Landing Characteristics of a 0.13-Scale Model of the Convair XFY-1 Vertically Rising Airplane in Steady Winds, TED No. NACA DE 368

    NASA Technical Reports Server (NTRS)

    Schade, Robert O.; Smith, Charles C., Jr.; Lovell, P. M., Jr.

    1954-01-01

    An experimental investigation has been conducted to determine the stability and control characteristics of a 0.13-scale free-flight model of the Convair XFY-1 airplane during take-offs and landings in steady winds. The tests indicated that take-offs in headwinds up to at least 20 knots (full scale) will be fairly easy to perform although the airplane may be blown downstream as much as 3 spans before a trim condition can be established. The distance that the airplane will be blown down-stream can be reduced by restraining the upwind landing gear until the instant of take-off. The tests also indicated that spot landings in headwinds up to at least 30 knots (full scale) and in crosswinds up to at least 20 knots (full scale) can be accomplished with reasonable accuracy although, during the landing approach, there will probably be an undesirable nosing-up tendency caused by ground effect and by the change in angle of attack resulting from vertical descent. Some form of arresting gear will probably be required to prevent the airplane from rolling downwind or tipping over after contact. This rolling and tipping can be prevented by a snubbing line attached to the tip of the upwind' wing or tail or by an arresting gear consisting of a wire mesh on the ground and hooks on the landing gear to engage the mesh.

  13. Aerial photographic reproductions

    USGS Publications Warehouse

    U.S. Geological Survey

    1975-01-01

    The National Cartographic Information Center of the U.S. Geological Survey maintains records of aerial photographic coverage of the United States and its Territories, based on reports from other Federal agencies as well as State governmental agencies and commercial companies. From these records, the Center furnishes data to prospective purchasers on available photography and the agency holding the aerial film.

  14. SR-71A Taking Off with Test Fixture Mounted Atop the Aft Section of the Aircraft and F-18 Chase Airc

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This photo shows a NASA's SR-71A Blackbird, followed by a NASA F/A-18 chase plane, taking off from the runway at the Dryden Flight Research Center, Edwards, California, on a 1999 flight. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and sideslip, which are normally obtained with small tubes and vanes extending into the airstream. One of Dryden's SR-71s was used for the Linear Aerospike Rocket Engine, or LASRE Experiment. Another earlier project consisted of a series of flights using the SR-71 as a science camera platform for NASA's Jet Propulsion Laboratory in Pasadena, California. An upward

  15. Postural Tachycardia Syndrome (POTS)

    PubMed Central

    Low, Phillip A.; Sandroni, Paola; Joyner, Michael; Shen, Win-Kuang

    2014-01-01

    Introduction POTS is defined as the development of orthostatic symptoms associated with a heart rate (HR) increment ≥30, usually to ≥120 bpm without orthostatic hypotension. Symptoms of orthostatic intolerance are those due to brain hypoperfusion and those due to sympathetic overaction. Methods We provide a review of POTS based primarily on work from the Mayo Clinic. Results Females predominate over males by 5:1. Mean age of onset in adults is about 30 years and most patients are between the ages of 20–40 years. Pathophysiologic mechanisms (not mutually exclusive) include peripheral denervation, hypovolemia, venous pooling, β-receptor supersensitivity, psychologic mechanisms, and presumed impairment of brain stem regulation. Prolonged deconditioning may also interact with these mechanisms to exacerbate symptoms. The evaluation of POTS requires a focused history and examination, followed by tests that should include HUT, some estimation of volume status and preferably some evaluation of peripheral denervation and hyperadrenergic state. All patients with POTS require a high salt diet, copious fluids, and postural training. Many require β-receptor antagonists in small doses and low-dose vasoconstrictors. Somatic hypervigilance and psychologic factors are involved in a significant proportion of patients. Conclusions POTS is heterogeneous in presentation and mechanisms. Major mechanisms are denervation, hypovolemia, deconditioning, and hyperadrenergic state. Most patients can benefit from a pathophysiologically based regimen of management. PMID:19207771

  16. Postural threat influences conscious perception of postural sway.

    PubMed

    Cleworth, Taylor W; Carpenter, Mark G

    2016-05-01

    This study examined how changes in threat influenced conscious perceptions of postural sway. Young healthy adults stood on a forceplate mounted to a hydraulic lift placed at two heights (0.8m and 3.2m). At each height, subjects stood quietly with eyes open and eyes closed for 60s. Subjects were instructed to either stand normal, or stand normal and track their perceived sway in the antero-posterior plane by rotating a hand-held potentiometer. Participants reported an increased level of fear, anxiety, arousal and a decreased level of balance confidence when standing at height. In addition, postural sway amplitude decreased and frequency increased at height. However, there were no effects of height on perceived sway. When standing under conditions of increased postural threat, sway amplitude is reduced, while sway perception appears to remain unchanged. Therefore, when threat is increased, sensory gain may be increased to compensate for postural strategies that reduce sway (i.e. stiffening strategy), thereby ensuring sufficient afferent information is available to maintain, or even increase the conscious perception of postural sway. PMID:27016388

  17. Tank Tests of a 1/7-Size Dynamic Model of the Grumman XJR2F-1 Amphibian to Determine the Effect of Slotted- and Split-Type Flaps on Take-Off Stability - NACA Model 212, TED No. NACA 2378

    NASA Technical Reports Server (NTRS)

    Land, Norman S.; Zeck, Howard

    1947-01-01

    Additional tests of a 1/7-size model of the Grumman XJR2F-1 amphibian were made in Langley tank no. 1 to compare the behavior during take-off of the model equipped with split- and slotted-type flaps. The slotted flag had a large effect on locating the forward center-of-gravity limits for stable take-offs. Stable take-offs within the normal operating range of positions of the center of gravity could be made with the split flaps deflected 45deg or with the slotted flaps deflected less than 20deg. At flap deflections required for similar take-off stability, the use of split-flaps resulted lower take-off speeds than the use of slotted flaps. An increase in forward acceleration from 1.1 to 4.8 feet per second per second moved the center-of-gravity limit forward approximately 3-percent mean aerodynamic chord.

  18. Vestibular humanoid postural control.

    PubMed

    Mergner, Thomas; Schweigart, Georg; Fennell, Luminous

    2009-01-01

    Many of our motor activities require stabilization against external disturbances. This especially applies to biped stance since it is inherently unstable. Disturbance compensation is mainly reactive, depending on sensory inputs and real-time sensor fusion. In humans, the vestibular system plays a major role. When there is no visual space reference, vestibular-loss clearly impairs stance stability. Most humanoid robots do not use a vestibular system, but stabilize upright body posture by means of center of pressure (COP) control. We here suggest using in addition a vestibular sensor and present a biologically inspired vestibular sensor along with a human-inspired stance control mechanism. We proceed in two steps. First, in an introductory review part, we report on relevant human sensors and their role in stance control, focusing on own models of transmitter fusion in the vestibular sensor and sensor fusion in stance control. In a second, experimental part, the models are used to construct an artificial vestibular system and to embed it into the stance control of a humanoid. The robot's performance is investigated using tilts of the support surface. The results are compared to those of humans. Functional significance of the vestibular sensor is highlighted by comparing vestibular-able with vestibular-loss states in robot and humans. We show that a kinematic body-space sensory feedback (vestibular) is advantageous over a kinetic one (force cues) for dynamic body-space balancing. Our embodiment of human sensorimotor control principles into a robot is more than just bionics. It inspired our biological work (neurorobotics: 'learning by building', proof of principle, and more). We envisage a future clinical use in the form of hardware-in-the-loop simulations of neurological symptoms for improving diagnosis and therapy and designing medical assistive devices. PMID:19665555

  19. Automatic and Interactive Key Posture Design by Combing the PIK with Parametric Posture Splicing

    NASA Astrophysics Data System (ADS)

    Li, Shilei; Wu, Bing; Liang, Jiahong; Su, Jiongming

    Key posture design is commonly needed in computer animation. This paper presents an automatic and interactive whole body posture designing technique by combining the PIK (prioritized inverse kinematics) with the proposed parametric human posture splicing technique. The key feature of PIK is that the user can design a posture by adding high level constraints with different priorities. However, the PIK is essentially a numerical IK algorithm which relies on the iterative optimization starting from a good enough initial posture to get the final result. To speed up the running efficiency and ensure the lifelikeness of the final posture, the parametric posture splicing technique is proposed to generate the initial guess of the PIK. According to the set of the high level constraints, the whole body is divided into some partial parts, whose postures are then generated by the parametric posture synthesis from a single posture database. Then an initial posture guess with some main characteristics of the finally acceptable posture can be generated approximately by splicing these partial body postures together. Starting from this initial guess and with all constraints considered at different priority levels, the PIK can be initialized with a bias defined by this particularly initial guess and iterated step by step to get a final posture. The total process of the whole body posture generation is automatic and interactive. The experimental results show that this combination method can not only improve the computation efficiency of the PIK but also can simultaneously ensure the naturalness of the final posture.

  20. Investigation of the Effectiveness of Boundary-layer Control by Blowing over a Combination of Sliding and Plain Flaps in Deflecting a Propeller Slipstream Downward for Vertical Take-off

    NASA Technical Reports Server (NTRS)

    Spreemann, Kenneth P; Kuhn, Richard E

    1956-01-01

    An investigation was conducted in order to determine the effectiveness of blowing a jet of air over the flaps of a wing equipped with a 50-percent-chord sliding flap and a 25-percent-chord plain flap in deflecting a propeller slipstream downward for vertical take-off and the results are presented herein. The effects of a leading-edge slat, ground proximity, end plate, and propeller position were also investigated. The tests were conducted in a static-thrust facility at the Langley Aeronautical Laboratory.

  1. Flight Tests of a Model of a High-wing Transport Vertical-take-off Airplane with Tilting Wing and Propellers and with Jet Controls at the Rear of the Fuselage for Pitch and Yaw Control

    NASA Technical Reports Server (NTRS)

    Lovell, Powell M , Jr; Parlett, Lysle P

    1957-01-01

    An investigation of the stability and control of a high-wing transport vertical-take-off airplane with four engines during constant-altitude transitions from hovering to normal forward flight was conducted with a remotely controlled free-flight model. The model had four propellers distributed along the wing with the thrust axes in the wing chord plane. The wing could be rotated to 90 degrees incidence so that the propeller thrust axes were vertical for hovering flight. An air jet at the rear of the fuselage provided pitch and yaw control for hovering and low-speed flight.

  2. Age Related Decline in Postural Control Mechanisms.

    ERIC Educational Resources Information Center

    Stelmach, George E.; And Others

    1989-01-01

    Studied voluntary and reflexive mechanisms of postural control of young (N=8) and elderly (N=8) adults through measurement of reflexive reactions to large-fast and small-slow ankle rotation postural disturbances. Found reflexive mechanisms relatively intact for both groups although elderly appeared more disadvantaged when posture was under the…

  3. Recognizing postural orthostatic tachycardia syndrome.

    PubMed

    Pavlik, Daniel; Agnew, Donna; Stiles, Lauren; Ditoro, Rachel

    2016-04-01

    This article describes the pathophysiology, clinical presentation, differential diagnosis, diagnosis, and management of postural orthostatic tachycardia syndrome (POTS), a potentially debilitating autonomic disorder that can have many causes and presentations. POTS can be mistaken for panic disorder, inappropriate sinus tachycardia, and chronic fatigue syndrome. Clinician suspicion for the syndrome is key to prompt patient diagnosis and treatment. PMID:26967958

  4. Nonstationary properties of postural sway.

    PubMed

    Carroll, J P; Freedman, W

    1993-01-01

    Postural sway during quite stance is usually assumed to be a stationary stochastic process. We tested this assumption by investigating the time invariance of the average value and variance of the postural sway of three subjects. The sway was measured with a force plate under three conditions: subject standing on two feet with eyes open; subject standing on two feet with eyes closed; and subject standing on one foot with eyes open. Data were collected in 1 min runs. More than 50 min of data were collected for each subject under each test condition. The data were averaged across all runs for each subject and condition. Trends were found to be present in the data. In addition, there were initial transient increases in the second-order moments about the trends. The transient changes in first- and second-order moments usually disappeared during the first 20 s. In light of these findings, we can reject the hypothesis that postural sway is a stationary process. The results imply that the usual methods to parameterize postural sway have to be either changed or reinterpreted. PMID:8478345

  5. Aerial Photography Summary Record System

    USGS Publications Warehouse

    U.S. Geological Survey

    1998-01-01

    The Aerial Photography Summary Record System (APSRS) describes aerial photography projects that meet specified criteria over a given geographic area of the United States and its territories. Aerial photographs are an important tool in cartography and a number of other professions. Land use planners, real estate developers, lawyers, environmental specialists, and many other professionals rely on detailed and timely aerial photographs. Until 1975, there was no systematic approach to locate an aerial photograph, or series of photographs, quickly and easily. In that year, the U.S. Geological Survey (USGS) inaugurated the APSRS, which has become a standard reference for users of aerial photographs.

  6. Does Observation of Postural Imbalance Induce a Postural Reaction?

    PubMed Central

    Tia, Banty; Saimpont, Arnaud; Paizis, Christos; Mourey, France; Fadiga, Luciano; Pozzo, Thierry

    2011-01-01

    Background Several studies bring evidence that action observation elicits contagious responses during social interactions. However automatic imitative tendencies are generally inhibited and it remains unclear in which conditions mere action observation triggers motor behaviours. In this study, we addressed the question of contagious postural responses when observing human imbalance. Methodology/Principal Findings We recorded participants' body sway while they observed a fixation cross (control condition), an upright point-light display of a gymnast balancing on a rope, and the same point-light display presented upside down. Our results showed that, when the upright stimulus was displayed prior to the inverted one, centre of pressure area and antero-posterior path length were significantly greater in the upright condition compared to the control and upside down conditions. Conclusions/Significance These results demonstrate a contagious postural reaction suggesting a partial inefficiency of inhibitory processes. Further, kinematic information was sufficient to trigger this reaction. The difference recorded between the upright and upside down conditions indicates that the contagion effect was dependent on the integration of gravity constraints by body kinematics. Interestingly, the postural response was sensitive to habituation, and seemed to disappear when the observer was previously shown an inverted display. The motor contagion recorded here is consistent with previous work showing vegetative output during observation of an effortful movement and could indicate that lower level control facilitates contagion effects. PMID:21423622

  7. Aerial Explorers and Robotic Ecosystems

    NASA Technical Reports Server (NTRS)

    Young, Larry A.; Pisanich, Greg

    2004-01-01

    A unique bio-inspired approach to autonomous aerial vehicle, a.k.a. aerial explorer technology is discussed. The work is focused on defining and studying aerial explorer mission concepts, both as an individual robotic system and as a member of a small robotic "ecosystem." Members of this robotic ecosystem include the aerial explorer, air-deployed sensors and robotic symbiotes, and other assets such as rovers, landers, and orbiters.

  8. Aerial photographic reproductions

    USGS Publications Warehouse

    U.S. Geological Survey

    1971-01-01

    Geological Survey vertical aerial photography is obtained primarily for topographic and geologic mapping. Reproductions from this photography are usually satisfactory for general use. Because reproductions are not stocked, but are custom processed for each order, they cannot be returned for credit or refund.

  9. Aerial of the VAB

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Even in this aerial view at KSC, the Vehicle Assembly Building is imposing. In front of it is the Launch Control Center. In the background is the Rotation/Processing Facility, next to the Banana Creek. In the foreground is the Saturn Causeway that leads to Launch Pads 39A and 39B.

  10. Aerial Perspective Artistry

    ERIC Educational Resources Information Center

    Wolfe, Linda

    2010-01-01

    This article presents a lesson centering on aerial perspective artistry of students and offers suggestions on how art teachers should carry this project out. This project serves to develop students' visual perception by studying reproductions by famous artists. This lesson allows one to imagine being lured into a landscape capable of captivating…

  11. The Steps to Perfect Posture

    ERIC Educational Resources Information Center

    Chappell, Jon

    2007-01-01

    Many people have memories of being told to "stop slouching" while seated at the piano bench. But the reality is that good piano posture is not as simple as bolting upright on the bench when the teacher barks. According to Eric Sutz, a Chicago-area piano teacher and performer, one should see a natural curve in his/her lower lumbar area and should…

  12. Investigation of Effectiveness of a Wing Equipped with a 50-percent-chord Sliding Flap, a 30-percent-chord Slotted Flap, and a 30-percent-chord Slat in Deflecting Propeller Slipstreams Downward for Vertical Take-off

    NASA Technical Reports Server (NTRS)

    Kuhn, Richard E

    1957-01-01

    Results are presented of an investigation of the effectiveness of a wing equipped with a 50-percent-chord sliding flap and a 30-percent-chord slotted flap in deflecting a propeller slipstream downward for vertical take-off. Tests were conducted at zero forward speed in a large room and included the effects of flap deflection, proximity to the ground, a leading-edge slat, and end plates. A turning angle of about 70 degrees and a resultant force of about 100 percent of the thrust were achieved near the ground. Out of the ground-effect region, the turning angle was also about 70 degrees but the resultant force was reduced to about 86 percent of the thrust.

  13. Articulatory constraints on interpersonal postural coordination.

    PubMed

    Shockley, Kevin; Baker, Aimee A; Richardson, Michael J; Fowler, Carol A

    2007-02-01

    Cooperative conversation has been shown to foster interpersonal postural coordination. The authors investigated whether such coordination is mediated by the influence of articulation on postural sway. In Experiment 1, talkers produced words in synchrony or in alternation, as the authors varied speaking rate and word similarity. Greater shared postural activity was found for the faster speaking rate. In Experiment 2, the authors demonstrated that shared postural activity also increases when individuals speak the same words or speak words that have similar stress patterns. However, this increase in shared postural activity is present only when participants' data are compared with those of their partner, who was present during the task, but not when compared with the data of a member of a different pair speaking the same word sequences as those of the original partner. The authors' findings suggest that interpersonal postural coordination observed during conversation is mediated by convergent speaking patterns. PMID:17311488

  14. Postural Stability is Altered by Blood Shift

    NASA Astrophysics Data System (ADS)

    Marais, M.; Denise, P.; Guincetre, J. Y.; Normand, H.

    2008-06-01

    Non-vestibular influences as shift in blood volume changed perception of body posture. Then, factors affecting blood shift may alter postural control. The purpose of our study was to investigate the effects of leg venous contention on postural stability. Twelve subjects were studied on a balance plate for 5 minutes with the eyes closed, in 3 conditions: with no leg venous contention or grade 1 and 3 support stockings. Standard deviation of x and y position was calculated before and after the closure of the eyes. Strong venous contention altered postural stability, after the eyes were closed, during the first 10 s of standing. As support stockings prevent blood shift induced by upright posture, this result is in line with the hypothesis that blood shifts influence the perception of body orientation and postural control among others factors as vision, vestibular inputs... This strong venous contention could induce an increase of fall.

  15. Common postural defects among music students.

    PubMed

    Blanco-Piñeiro, Patricia; Díaz-Pereira, M Pino; Martínez, Aurora

    2015-07-01

    Postural quality during musical performance affects both musculoskeletal health and the quality of the performance. In this study we examined the posture of 100 students at a Higher Conservatory of Music in Spain. By analysing video tapes and photographs of the students while performing, a panel of experts extracted values of 11 variables reflecting aspects of overall postural quality or the postural quality of various parts of the body. The most common postural defects were identified, together with the situations in which they occur. It is concluded that most students incur in unphysiological postures during performance. It is hoped that use of the results of this study will help correct these errors. PMID:26118530

  16. The neuropathic postural tachycardia syndrome

    NASA Technical Reports Server (NTRS)

    Jacob, G.; Costa, F.; Shannon, J. R.; Robertson, R. M.; Wathen, M.; Stein, M.; Biaggioni, I.; Ertl, A.; Black, B.; Robertson, D.

    2000-01-01

    BACKGROUND: The postural tachycardia syndrome is a common disorder that is characterized by chronic orthostatic symptoms and a dramatic increase in heart rate on standing, but that does not involve orthostatic hypotension. Several lines of evidence indicate that this disorder may result from sympathetic denervation of the legs. METHODS: We measured norepinephrine spillover (the rate of entry of norepinephrine into the venous circulation) in the arms and legs both before and in response to exposure to three stimuli (the cold pressor test, sodium nitroprusside infusion, and tyramine infusion) in 10 patients with the postural tachycardia syndrome and in 8 age- and sex-matched normal subjects. RESULTS: At base line, the mean (+/-SD) plasma norepinephrine concentration in the femoral vein was lower in the patients with the postural tachycardia syndrome than in the normal subjects (135+/-30 vs. 215+/-55 pg per milliliter [0.80+/-0.18 vs. 1.27+/-0.32 nmol per liter], P=0.001). Norepinephrine spillover in the arms increased to a similar extent in the two groups in response to each of the three stimuli, but the increases in the legs were smaller in the patients with the postural tachycardia syndrome than in the normal subjects (0.001+/-0.09 vs. 0.12+/-0.12 ng per minute per deciliter of tissue [0.006+/-0.53 vs. 0.71+/-0.71 nmol per minute per deciliter] with the cold pressor test, P=0.02; 0.02+/-0.07 vs. 0.23+/-0.17 ng per minute per deciliter [0.12+/-0.41 vs. 1.36+/-1.00 nmol per minute per deciliter] with nitroprusside infusion, P=0.01; and 0.008+/-0.09 vs. 0.19+/-0.25 ng per minute per deciliter [0.05+/-0.53 vs. 1.12+/-1.47 nmol per minute per deciliter] with tyramine infusion, P=0.04). CONCLUSIONS: The neuropathic postural tachycardia syndrome results from partial sympathetic denervation, especially in the legs.

  17. Reduce torques and stick the landing: limb posture during landing in toads.

    PubMed

    Azizi, Emanuel; Larson, Neil P; Abbott, Emily M; Danos, Nicole

    2014-10-15

    A controlled landing, where an animal does not crash or topple, requires enough stability to allow muscles to effectively dissipate mechanical energy. Toads (Rhinella marina) are exemplary models for understanding the mechanics and motor control of landing given their ability to land consistently during bouts of continuous hopping. Previous studies in anurans have shown that ground reaction forces (GRFs) during landing are significantly higher compared with takeoff and can potentially impart large torques about the center of mass (COM), destabilizing the body at impact. We predict that in order to minimize such torques, toads will align their COM with the GRF vector during the aerial phase in anticipation of impact. We combined high-speed videography and force-plate ergometry to quantify torques at the COM and relate the magnitude of torques to limb posture at impact. We show that modulation of hindlimb posture can shift the position of the COM by about 20% of snout-vent length. Rapid hindlimb flexion during the aerial phase of a hop moved the COM anteriorly and reduced torque by aligning the COM with the GRF vector. We found that the addition of extrinsic loads did not significantly alter landing behavior but did change the torques experienced at impact. We conclude that anticipatory hindlimb flexion during the aerial phase of a hop is a critical feature of a mechanically stable landing that allows toads to quickly string together multiple, continuous hops. PMID:25320271

  18. NEW APPROACHES: High temperature superconductors take off

    NASA Astrophysics Data System (ADS)

    Gough, Colin

    1998-01-01

    This article describes the progress made towards real engineering applications of high temperature superconductors (HTS) in the ten years following the Nobel Prize winning discovery by Bednorz and Müller in August 1986. Examples include HTS wires and tapes for more efficient and powerful electric motors and for increasing the electrical power into the heart of modern cities, HTS permanent magnets for levitation, microwave filters for cellular telephone networks, SQUIDs (superconducting quantum interference devices) to monitor foetal heart and brain signals, and a new generation of superfast logic devices based on the flux quantum.

  19. A Flight Simulator Program Takes Off

    ERIC Educational Resources Information Center

    McMahon, Don

    2003-01-01

    Aviation concepts, including forces acting on an airplane, navigation, correct aircraft terminology, and general aviation vocabulary, are often part of a comprehensive fifth-grade aviation curriculum. But in one school district, students also learned about flying planes and even trained in a flight simulator. This article describes how industry…

  20. X-36 Taking off During First Flight

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The X-36 remotely piloted aircraft lifts off on its first flight, May 17, 1997, at NASA's Dryden Flight Research Center, Edwards, California. The aircraft flew for five minutes and reached an altitude of approximately 4,900 feet. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems and the risks associated with their inability to deal with unknown or unforeseen phenomena in flight. Fully fueled the X-36 prototype weighed approximately 1,250 pounds. It was 19 feet long and three feet high with a wingspan of just over 10 feet. A Williams International F112 turbofan engine provided close to 700 pounds of thrust. A typical research flight lasted 35 to 45 minutes from takeoff to touchdown. A total of 31 successful research flights were flown from May 17, 1997, to November 12, 1997, amassing 15 hours and 38 minutes of flight time. The aircraft reached an altitude of 20,200 feet and a maximum angle of attack of 40 degrees. In a follow-on effort, the Air Force Research Laboratory (AFRL), Wright-Patterson Air Force Base, Ohio, contracted with Boeing to fly AFRL's Reconfigurable Control for Tailless Fighter Aircraft (RESTORE) software as a demonstration of the adaptability of the neural-net algorithm to compensate for in-flight damage or malfunction of effectors, such as flaps, ailerons and rudders. Two RESTORE research flights were flown in December 1998, proving the viability of the software approach. The X-36 aircraft flown at the Dryden Flight Research Center in 1997 was a 28-percent scale representation of a theoretical advanced fighter aircraft. The Boeing Phantom Works (formerly McDonnell Douglas) in St. Louis, Missouri, built two of the vehicles in a cooperative agreement with the Ames Research Center, Moffett Field, California.

  1. X-36 Taking off during First Flight

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The remotely-piloted X-36 Tailless Fighter Agility Research Aircraft lifts off from Rogers Dry Lake at the Dryden Flight Research Center on its first flight on May 17, 1997. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems and the risks associated with their inability to deal with unknown or unforeseen phenomena in flight. Fully fueled the X-36 prototype weighed approximately 1,250 pounds. It was 19 feet long and three feet high with a wingspan of just over 10 feet. A Williams International F112 turbofan engine provided close to 700 pounds of thrust. A typical research flight lasted 35 to 45 minutes from takeoff to touchdown. A total of 31 successful research flights were flown from May 17, 1997, to November 12, 1997, amassing 15 hours and 38 minutes of flight time. The aircraft reached an altitude of 20,200 feet and a maximum angle of attack of 40 degrees. In a follow-on effort, the Air Force Research Laboratory (AFRL), Wright-Patterson Air Force Base, Ohio, contracted with Boeing to fly AFRL's Reconfigurable Control for Tailless Fighter Aircraft (RESTORE) software as a demonstration of the adaptability of the neural-net algorithm to compensate for in-flight damage or malfunction of effectors, such as flaps, ailerons and rudders. Two RESTORE research flights were flown in December 1998, proving the viability of the software approach. The X-36 aircraft flown at the Dryden Flight Research Center in 1997 was a 28-percent scale representation of a theoretical advanced fighter aircraft. The Boeing Phantom Works (formerly McDonnell Douglas) in St. Louis, Missouri, built two of the vehicles in a cooperative agreement with the Ames Research Center, Moffett Field, California.

  2. Discovery Takes Off on New Mission

    NASA Video Gallery

    Space shuttle Discovery began its next mission April 17, 2012, when it took off from its operational home and headed to the Smithsonian Institution where it will be put on display to inspire the pu...

  3. NASA's Global Hawk 871 Takes Off

    NASA Video Gallery

    NASA's Global Hawk 871 departed from a runway at NASA's Wallops Flight Facility, Wallops Island, Va. on Sept. 25, 2013 at the close of the NASA HS3 Hurricane Mission. NASA 871 was returning to home...

  4. Dynamic Control of Posture Across Locomotor Tasks

    PubMed Central

    Earhart, Gammon M.

    2013-01-01

    Successful locomotion depends on postural control to establish and maintain appropriate postural orientation of body segments relative to one another and to the environment, and to ensure dynamic stability of the moving body. This paper provides a framework for considering dynamic postural control, highlighting the importance of coordination, consistency, and challenges to postural control posed by various locomotor tasks such as turning and backward walking. The impacts of aging and various movement disorders on postural control are discussed broadly in an effort to provide a general overview of the field and recommendations for assessment of dynamic postural control across different populations in both clinical and research settings. Suggestions for future research on dynamic postural control during locomotion are also provided and include discussion of opportunities afforded by new and developing technologies, the need for long-term monitoring of locomotor performance in everyday activities, gaps in our knowledge of how targeted intervention approaches modify dynamic postural control, and the relative paucity of literature regarding dynamic postural control in movement disorder populations other than Parkinson disease. PMID:24132838

  5. AERIAL RADIOLOGICAL SURVEYS

    SciTech Connect

    Proctor, A.E.

    1997-06-09

    Measuring terrestrial gamma radiation from airborne platforms has proved to be a useful method for characterizing radiation levels over large areas. Over 300 aerial radiological surveys have been carried out over the past 25 years including U.S. Department of Energy (DOE) sites, commercial nuclear power plants, Formerly Utilized Sites Remedial Action Program/Uranium Mine Tailing Remedial Action Program (FUSRAP/UMTRAP) sites, nuclear weapons test sites, contaminated industrial areas, and nuclear accident sites. This paper describes the aerial measurement technology currently in use by the Remote Sensing Laboratory (RSL) for routine environmental surveys and emergency response activities. Equipment, data-collection and -analysis methods, and examples of survey results are described.

  6. [Postural examination in daily occlusodontology].

    PubMed

    Serviere, F

    1989-03-01

    According to the osteopathic and chiropractic concepts, facing a TMJ problem, the practitioner has to determine if the trouble observed in the stomatognatic apparatus is the cause or the effect of the structural problems present anywhere else in the body. The postural examination allows to answer this question. Tow techniques can be used. First a static and dynamic posture test proposed by Bricot. The level of the cranium, the eyes, the shoulders, the wrists, the pelvis and the ankles is analysed, from a front view; from the side, the gravity line is inspected: vertex, auditory meatus, shoulder, hip joint, anterior side of the tibia, ankle joint. The vertical posture can be studied from the front: the arms are held straight and the antero-posterior length between the fingers is measured. From the back, one notes the recoil of the buttocks on one side. An ocular convergence test is performed. Then one uses a Romberg test (oscillation of the body when the eyes are closed), and a Fukuda stepping test. The patient is then asked to bite on a compress, and the same exams are redone. If no change occurs, we are dealing with an ascending problem: the origin of the problem is not the stomatognathic system. The second technique is the Meerssemann test that needs the practice of Applied Kinesiology muscle testing. The patient is lying supine and one tests: the dental occlusion, the two TMJs, the temporal muscles, masseters, pterygoids, sterno-cleido-mastoids, upper tapezius, left and right sacro-iliac joints, psoas muscles bilaterally.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2636023

  7. Variations in Writing Posture and Cerebral Organization

    ERIC Educational Resources Information Center

    Levy, Jerre; Reid, Marylou

    1976-01-01

    Investigated the relationship between hand writing posture and cerebral dominance of 48 left handed writers and 25 right handed writers. Determined that cerebral dominance is related to handedness and to whether or not the writing hand posture is normal or inverted. (SL)

  8. Articulatory Constraints on Interpersonal Postural Coordination

    ERIC Educational Resources Information Center

    Shockley, Kevin; Baker, Aimee A.; Richardson, Michael J.; Fowler, Carol A.

    2007-01-01

    Cooperative conversation has been shown to foster interpersonal postural coordination. The authors investigated whether such coordination is mediated by the influence of articulation on postural sway. In Experiment 1, talkers produced words in synchrony or in alternation, as the authors varied speaking rate and word similarity. Greater shared…

  9. Neuromechanical tuning of nonlinear postural control dynamics

    NASA Astrophysics Data System (ADS)

    Ting, Lena H.; van Antwerp, Keith W.; Scrivens, Jevin E.; McKay, J. Lucas; Welch, Torrence D. J.; Bingham, Jeffrey T.; DeWeerth, Stephen P.

    2009-06-01

    Postural control may be an ideal physiological motor task for elucidating general questions about the organization, diversity, flexibility, and variability of biological motor behaviors using nonlinear dynamical analysis techniques. Rather than presenting "problems" to the nervous system, the redundancy of biological systems and variability in their behaviors may actually be exploited to allow for the flexible achievement of multiple and concurrent task-level goals associated with movement. Such variability may reflect the constant "tuning" of neuromechanical elements and their interactions for movement control. The problem faced by researchers is that there is no one-to-one mapping between the task goal and the coordination of the underlying elements. We review recent and ongoing research in postural control with the goal of identifying common mechanisms underlying variability in postural control, coordination of multiple postural strategies, and transitions between them. We present a delayed-feedback model used to characterize the variability observed in muscle coordination patterns during postural responses to perturbation. We emphasize the significance of delays in physiological postural systems, requiring the modulation and coordination of both the instantaneous, "passive" response to perturbations as well as the delayed, "active" responses to perturbations. The challenge for future research lies in understanding the mechanisms and principles underlying neuromechanical tuning of and transitions between the diversity of postural behaviors. Here we describe some of our recent and ongoing studies aimed at understanding variability in postural control using physical robotic systems, human experiments, dimensional analysis, and computational models that could be enhanced from a nonlinear dynamics approach.

  10. Correcting Poor Posture without Awareness or Willpower

    ERIC Educational Resources Information Center

    Wernik, Uri

    2012-01-01

    In this article, a new technique for correcting poor posture is presented. Rather than intentionally increasing awareness or mobilizing willpower to correct posture, this approach offers a game using randomly drawn cards with easy daily assignments. A case using the technique is presented to emphasize the subjective experience of living with poor…

  11. Postural Variables in Girls Practicing Volleyball

    ERIC Educational Resources Information Center

    Grabara, Malgorzata; Hadzik, Andrzej

    2009-01-01

    Study aim: To assess body posture of young female volleyball players in relation to their untrained mates. Material and methods: A group of 42 volleyball players and another of 43 untrained girls, all aged 13-16 years were studied with respect to their body posture indices by using computer posturography. Spinal angles and curvatures were…

  12. Postural Coordination during Socio-motor Improvisation

    PubMed Central

    Gueugnon, Mathieu; Salesse, Robin N.; Coste, Alexandre; Zhao, Zhong; Bardy, Benoît G.; Marin, Ludovic

    2016-01-01

    Human interaction often relies on socio-motor improvisation. Creating unprepared movements during social interaction is not a random process but relies on rules of synchronization. These situations do not only involve people to be coordinated, but also require the adjustment of their posture in order to maintain balance and support movements. The present study investigated posture in such a context. More precisely, we first evaluated the impact of amplitude and complexity of arm movements on posture in solo situation. Then, we assessed the impact of interpersonal coordination on posture using the mirror game in which dyads performed improvised and synchronized movements (i.e., duo situation). Posture was measured through ankle-hip coordination in medio-lateral and antero-posterior directions (ML and AP respectively). Our results revealed the spontaneous emergence of in-phase pattern in ML direction and antiphase pattern in AP direction for solo and duo situations. These two patterns respectively refer to the simultaneous flexion/extension of the ankles and the hips in the same or opposite direction. It suggests different functional roles of postural coordination patterns in each direction, with in-phase supporting task performance in ML (dynamical stability) and antiphase supporting postural control in AP (mechanical stability). Although amplitude of movement did not influence posture, movement complexity disturbed postural stability in both directions. Conversely, interpersonal coordination promoted postural stability in ML but not in AP direction. These results are discussed in terms of the difference in coupling strength between ankle-hip coordination and interpersonal coordination. PMID:27547193

  13. Postural Coordination during Socio-motor Improvisation.

    PubMed

    Gueugnon, Mathieu; Salesse, Robin N; Coste, Alexandre; Zhao, Zhong; Bardy, Benoît G; Marin, Ludovic

    2016-01-01

    Human interaction often relies on socio-motor improvisation. Creating unprepared movements during social interaction is not a random process but relies on rules of synchronization. These situations do not only involve people to be coordinated, but also require the adjustment of their posture in order to maintain balance and support movements. The present study investigated posture in such a context. More precisely, we first evaluated the impact of amplitude and complexity of arm movements on posture in solo situation. Then, we assessed the impact of interpersonal coordination on posture using the mirror game in which dyads performed improvised and synchronized movements (i.e., duo situation). Posture was measured through ankle-hip coordination in medio-lateral and antero-posterior directions (ML and AP respectively). Our results revealed the spontaneous emergence of in-phase pattern in ML direction and antiphase pattern in AP direction for solo and duo situations. These two patterns respectively refer to the simultaneous flexion/extension of the ankles and the hips in the same or opposite direction. It suggests different functional roles of postural coordination patterns in each direction, with in-phase supporting task performance in ML (dynamical stability) and antiphase supporting postural control in AP (mechanical stability). Although amplitude of movement did not influence posture, movement complexity disturbed postural stability in both directions. Conversely, interpersonal coordination promoted postural stability in ML but not in AP direction. These results are discussed in terms of the difference in coupling strength between ankle-hip coordination and interpersonal coordination. PMID:27547193

  14. Aerial Video Imaging

    NASA Technical Reports Server (NTRS)

    1991-01-01

    When Michael Henry wanted to start an aerial video service, he turned to Johnson Space Center for assistance. Two NASA engineers - one had designed and developed TV systems in Apollo, Skylab, Apollo- Soyuz and Space Shuttle programs - designed a wing-mounted fiberglass camera pod. Camera head and angles are adjustable, and the pod is shaped to reduce vibration. The controls are located so a solo pilot can operate the system. A microprocessor displays latitude, longitude, and bearing, and a GPS receiver provides position data for possible legal references. The service has been successfully utilized by railroads, oil companies, real estate companies, etc.

  15. Force-Test Investigation of the Stability and Control Characteristics of a 1/4-Scale Model of a Tilt-Wing Vertical-Take-Off-and-Landing Aircraft

    NASA Technical Reports Server (NTRS)

    Newsom, William A., Jr.; Tosti, Louis P.

    1959-01-01

    A wind-tunnel investigation has been made to determine the aerodynamic characteristics of a 1/4-scale model of a tilt-wing vertical-take-off-and-landing aircraft. The model had two 3-blade single-rotation propellers with hinged (flapping) blades mounted on the wing, which could be tilted from an incidence of 4 deg for forward flight to 86 deg for hovering flight. The investigation included measurements of both the longitudinal and lateral stability and control characteristics in both the normal forward flight and the transition ranges. Tests in the forward-flight condition were made for several values of thrust coefficient, and tests in the transition condition were made at several values of wing incidence with the power varied to cover a range of flight conditions from forward-acceleration (or climb) conditions to deceleration (or descent) conditions The control effectiveness of the all-movable horizontal tail, the ailerons and the differential propeller pitch control was also determined. The data are presented without analysis.

  16. Tank Tests of a 1/7-Size Powered Dynamic Model of the Grumman XJR2F-1 Amphibian: Spray Characteristics, Take-Off and Landing Stability in Smooth Water - Langley Tank Model 212, TED No. NACA 2378

    NASA Technical Reports Server (NTRS)

    Land, Norman S.; Zeck, Howrad

    1946-01-01

    Tests of a model of the XJR2F-Y amphibian were made in Langley tank no. to determine the spray characteristics and the take-off and landing stability. At a gross load of 22,000 pounds full size, spray entered the propeller disk only at a very narrow range of speeds. The spray striking the flaps was not excessive and no appreciable wetting of the tail surfaces was noted. The trim limits of stability appeared to be satisfactory and the upper-limit porpoising was not violent. The stable range of center-of-gravity locations with flaps set 20deg was well aft of the desired operating range. However, with flaps up, the forward limit was about 18 percent mean aerodynamic chord and the aft limit about 28.5 percent mean aerodynamic chord at a load of 26,000 pounds and with elevators deflected -10deg. Under these conditions the location of the step is considered satisfactory. Tests showed that the effect of water in the nose-wheel well would be to move the forward limit aft about 2-percent mean aerodynamic chord. Without ventilation of the main step, the model skipped during landing at most trims, but this skipping was not violent. With the ventilation, the model skipped lightly only at trims where the afterbody keel was approximately parallel to the water (around 7.5 deg).

  17. Adaptation of Postural Stability following Stroke.

    PubMed

    Di Fabio, R P

    1997-01-01

    Activities of daily living require both anticipatory and reactive postural adjustments. The influence of stroke on anticipatory and reactive balance behaviors is addressed in this article. Two primary deficits appear to underlie postural instability following stroke. The first deficit type is characterized by a loss of postural muscle recruitment in both lower extremities (not hyperactive stretch reflexes). The second deficit type is related specifically to the lack of limb stabilization on the paretic side of the body. These two categories of deficit might result from the disruption of geocentric and egocentric references for postural stability with cerebrovascular disease. Context-dependent postural responses are either relearned or retained following stroke, but deficits in the sequencing and timing of stabilizing neuromuscular responses appear to be resistant to adaptation. Prior knowledge of an impending balance disturbance improves the initiation of reactive postural adjustments in subjects with stroke but has no effect on the initiation of stabilizing responses associated with voluntary motion. The results suggest that reactive and anticipatory postural adjustments are controlled by different neural mechanisms and may require separate attention in a rehabilitation program. PMID:27620375

  18. Recovery of postural equilibrium control following spaceflight

    NASA Technical Reports Server (NTRS)

    Paloski, W. H.; Reschke, M. F.; Black, F. O.; Doxey, D. D.; Harm, D. L.

    1992-01-01

    Decreased postural stability is observed in most astronauts immediately following spaceflight. Because ataxia may present postflight operational hazards, it is important to determine the incidence of postural instability immediately following landing and the dynamics of recovery of normal postural equilibrium control. It is postulated that postflight postural instability results from in-flight adaptive changes in central nervous system (CNS) processing of sensory information from the visual, vestibular, and proprioceptive systems. The purpose of the present investigation was to determine the magnitude and time course of postflight recovery of postural equilibrium control and, hence, readaptation of CNS processing of sensory information. Thirteen crew members from six spaceflight missions were studied pre- and postflight using a modified commercial posturography system. Postural equilibrium control was found to be seriously disrupted immediately following spaceflight in all subjects. Readaptation to the terrestrial environment began immediately upon landing, proceeded rapidly for the first 10-12 hours, and then proceeded much more slowly for the subsequent 2-4 days until preflight stability levels were reachieved. It is concluded that the overall postflight recovery of postural stability follows a predictable time course.

  19. Postural orthostatic tachycardia syndrome (POTS)

    PubMed Central

    Sidhu, Bharat; Obiechina, Nonyelum; Rattu, Noman; Mitra, Shanta

    2013-01-01

    Postural orthostatic tachycardia syndrome (POTS) is a heterogeneous group of conditions characterised by autonomic dysfunction and an exaggerated sympathetic response to assuming an upright position. Up till recently, it was largely under-recognised as a clinical entity. There is now consensus about the definition of POTS as a greater than 30/min heart rate increase on standing from a supine position (greater than 40/min increase in 12–19-year-old patients) or an absolute heart rate of greater than 120/min within 10 min of standing from a supine position and in the absence of hypotension, arrhythmias, sympathomimetic drugs or other conditions that cause tachycardia. We present two cases of POTS, followed by a discussion of its pathogenesis, pathophysiology, epidemiology and management. PMID:24042210

  20. Reversible postural orthostatic tachycardia syndrome

    PubMed Central

    Abdulla, Aza; Rajeevan, Thirumagal

    2015-01-01

    Postural orthostatic tachycardia syndrome (POTS) is a relatively rare syndrome recognised since 1940. It is a heterogenous condition with orthostatic intolerance due to dysautonomia and is characterised by rise in heart rate above 30 bpm from base line or to more than 120 bpm within 5-10 min of standing with or without change in blood pressure which returns to base line on resuming supine position. This condition present with various disabling symptoms such as light headedness, near syncope, fatigue, nausea, vomiting, tremor, palpitations and mental clouding, etc. However there are no identifiable signs on clinical examination and patients are often diagnosed to have anxiety disorder. The condition predominantly affects young female between the ages of 15-50 but is rarely described in older people. We describe an older patient who developed POTS which recovered over 12 mo. Recognising this condition is important as there are treatment options available to alleviate the disabling symptoms. PMID:26244158

  1. Adaptation to transient postural perturbations

    NASA Technical Reports Server (NTRS)

    Andres, Robert O.

    1992-01-01

    This research was first proposed in May, 1986, to focus on some of the problems encountered in the analysis of postural responses gathered from crewmembers. The ultimate driving force behind this line of research was the desire to treat, predict, or explain 'Space Adaptation Syndrome' (SAS) and hence circumvent any adverse effects of space motion sickness on crewmember performance. The aim of this project was to develop an easily implemented analysis of the transient responses to platform translation that can be elicited with a protocol designed to force sensorimotor reorganization, utilizing statistically reliable criterion measures. This report will present: (1) a summary of the activity that took place in each of the three funded years of the project; (2) discussion of experimental results and their implications for future research; and (3) a list of presentations and publications resulting from this project.

  2. Infrared film for aerial photography

    USGS Publications Warehouse

    Anderson, William H.

    1979-01-01

    Considerable interest has developed recently in the use of aerial photographs for agricultural management. Even the simplest hand-held aerial photographs, especially those taken with color infrared film, often provide information not ordinarily available through routine ground observation. When fields are viewed from above, patterns and variations become more apparent, often allowing problems to be spotted which otherwise may go undetected.

  3. AERIAL PHOTOGRAPHY AND LEGAL APPLICATIONS

    EPA Science Inventory

    Aerial photographic interpretation is the process of examining objects on aerial photographs and determining their significance. t is often defined as both art and science because the process, and the quality of the derived information, is often a qualitative nature and much depe...

  4. Postural correlates with painful situations

    PubMed Central

    Lelard, Thierry; Montalan, Benoît; Morel, Maria F.; Krystkowiak, Pierre; Ahmaidi, Said; Godefroy, Olivier; Mouras, Harold

    2013-01-01

    Background: Emotional context may play a crucial role in movement production. According to simulation theories, emotional states affect motor systems. The aim of this study was to compare postural responses assessed by posturography and electromyography when subjects were instructed to imagine themselves in a painful or a non-painful situation. Methods: Twenty-nine subjects (22.3 ± 3.7 years) participated in this study. While standing quietly on a posturographic platform, they were instructed to imagine themselves in a painful or non-painful situation. Displacement of the center of pressure (COP), leg muscle electromyographic activity, heart rate, and electrodermal activity were assessed in response to painful and non-painful situations. Results: The anteroposterior path was shorter (p < 0.05) when subjects imagined themselves in a painful situation (M = 148.0 ± 33.4 mm) compared to a non-painful situation (158.2 ± 38.7 mm). Higher tibialis anterior (TA) activity (RMS-TA = 3.38 ± 1.95% vs. 3.24 ± 1.85%; p < 0.001) and higher variability of soleus (SO) activity (variation coefficient of RMS-SO = 13.5 ± 16.2% vs. M = 9.0 ± 7.2%; p < 0.05) were also observed in painful compared to non-painful situations. No significant changes were observed for other physiological data. Conclusion: This study demonstrates that simulation of painful situations induces changes in postural control and leg muscle activation compared to non-painful situations, as increased stiffness was demonstrated in response to aversive pictures in accordance with previous results. PMID:23386816

  5. Trunk posture monitoring with inertial sensors

    PubMed Central

    Wong, Man Sang

    2008-01-01

    Measurement of human posture and movement is an important area of research in the bioengineering and rehabilitation fields. Various attempts have been initiated for different clinical application goals, such as diagnosis of pathological posture and movements, assessment of pre- and post-treatment efficacy and comparison of different treatment protocols. Image-based methods for measurements of human posture and movements have been developed, such as the radiography, photogrammetry, optoelectric technique and video analysis. However, it is found that these methods are complicated to set up, time-consuming to operate and could only be applied in laboratory environments. This study introduced a method of using a posture monitoring system in estimating the spinal curvature changes during trunk movements on the sagittal and coronal planes and providing trunk posture monitoring during daily activities. The system consisted of three sensor modules, each with one tri-axial accelerometer and three uni-axial gyroscopes orthogonally aligned, and a digital data acquisition and feedback system. The accuracy of this system was tested with a motion analysis system (Vicon 370) in calibration with experimental setup and in trunk posture measurement with nine human subjects, and the performance of the posture monitoring system during daily activities with two human subjects was reported. The averaged root mean squared differences between the measurements of the system and motion analysis system were found to be <1.5° in dynamic calibration, and <3.1° for the sagittal plane and ≤2.1° for the coronal plane in estimation of the trunk posture change during trunk movements. The measurements of the system and the motion analysis system was highly correlated (>0.999 for dynamic calibration and >0.829 for estimation of spinal curvature change in domain planes of movement during flexion and lateral bending). With the sensing modules located on the upper trunk, mid-trunk and the pelvic

  6. Limit cycle oscillations in standing human posture.

    PubMed

    Chagdes, James R; Rietdyk, Shirley; Haddad, Jeffrey M; Zelaznik, Howard N; Cinelli, Michael E; Denomme, Luke T; Powers, Kaley C; Raman, Arvind

    2016-05-01

    Limit cycle oscillations (LCOs) are a hallmark of dynamic instability in time-delayed and nonlinear systems such as climate change models, biological oscillators, and robotics. Here we study the links between the human neuromuscular system and LCOs in standing posture. First, we demonstrate through a simple mathematical model that the observation of LCOs in posture is indicative of excessive neuromuscular time-delay. To test this hypothesis we study LCOs in the postural sway of individuals with multiple sclerosis and concussed athletes representing two different populations with chronically and acutely increased neuromuscular time-delays. Using a wavelet analysis method we demonstrate that 67% of individuals with multiple sclerosis and 44% of individuals with concussion exhibit intermittent LCOs; 8% of MS-controls, 0% of older adults, and 0% of concussion-controls displayed LCOs. Thus, LCOs are not only key to understanding postural instability but also may have important applications for the detection of neuromuscular deficiencies. PMID:27018157

  7. Confounders of Vasovagal Syncope: Postural Tachycardia Syndrome

    PubMed Central

    Nwazue, Victor C.; Raj, Satish R

    2012-01-01

    Most patients who present to a cardiologist with syncope will have vasovagal (reflex) syncope. A busy syncope practice will often also see patients with postural tachycardia syndrome, often presenting with severe recurrent presyncope. Recognition of this “syncope confounder” might be difficult without adequate knowledge of their presentation, and this can adversely affect optimal management. Patients with postural tachycardia syndrome exhibit an excessive increase in heart rate ≥ 30 bpm within 10 minutes of standing (in the absence of orthostatic hypotension), in addition to chronic symptoms of orthostatic intolerance. Postural tachycardia syndrome can often be differentiated from vasovagal syncope by its hemodynamic pattern during tilt table test and differing clinical characteristics. This article will briefly review the presentation of postural tachycardia syndrome, its putative pathophysiology and an approach to non-pharmacological and pharmacological management. PMID:23217691

  8. Postural variability and sensorimotor development in infancy.

    PubMed

    Dusing, Stacey C

    2016-03-01

    Infants develop skills through a coupling between their sensory and motor systems. Newborn infants must interpret sensory information and use it to modify movements and organize the postural control system based on the task demands. This paper starts with a brief review of evidence on the use of sensory information in the first months of life, and describes the importance of movement variability and postural control in infancy. This introduction is followed by a review of the evidence for the interactions between the sensory, motor, and postural control systems in typically development infants. The paper highlights the ability of young infants to use sensory information to modify motor behaviors and learn from their experiences. Last, the paper highlights evidence of atypical use of sensory, motor, and postural control in the first months of life in infants who were born preterm, with neonatal brain injury or later diagnosed with cerebral palsy (CP). PMID:27027603

  9. Unmanned Aerial Systems for scientific research

    NASA Astrophysics Data System (ADS)

    Stefanutti, Leopoldo; MacKenzie, A. Robert; di Donfrancesco, Guido; Amici, Stefania

    2010-05-01

    could fly for over 20 hours over the ice pack or over the Antarctic continent could measure the horizontal and vertical extent of the ice sheet over unprecedented areas. Technical challenges, such as ensuring safe take-off and landing, appear not to be insurmountable. A second example is the study of the UTLS using a HALE platform such as the Global Hawk. Such a platform is well-suited for circumpolar flights, in which the same air masses could be encountered in a single flight, providing a quasi-lagrangian view of stratospheric ozone chemistry during the polar winter. Transects from the mid latitudes to the subtropics could also be designed, to study exchange processes across the tropopause and the age of air in the stratosphere. We will illustrate other possible scientific missions using other types of UAS platforms.

  10. Microgravity effects on 'postural' muscle activity patterns

    NASA Technical Reports Server (NTRS)

    Layne, Charles S.; Spooner, Brian S.

    1994-01-01

    Changes in neuromuscular activation patterns associated with movements made in microgravity can contribute to muscular atrophy. Using electromyography (EMG) to monitor 'postural' muscles, it was found that free floating arm flexions made in microgravity were not always preceded by neuromuscular activation patterns normally observed during movements made in unit gravity. Additionally, manipulation of foot sensory input during microgravity arm flexion impacted upon anticipatory postural muscle activation.

  11. AERIAL MEASURING SYSTEM IN JAPAN

    SciTech Connect

    Lyons, Craig; Colton, David

    2012-01-01

    The U.S. Department of Energy National Nuclear Security Agency’s Aerial Measuring System deployed personnel and equipment to partner with the U.S. Air Force in Japan to conduct multiple aerial radiological surveys. These were the first and most comprehensive sources of actionable information for U.S. interests in Japan and provided early confirmation to the government of Japan as to the extent of the release from the Fukushima Daiichi Nuclear Power Generation Station. Many challenges were overcome quickly during the first 48 hours; including installation and operation of Aerial Measuring System equipment on multiple U.S. Air Force Japan aircraft, flying over difficult terrain, and flying with talented pilots who were unfamiliar with the Aerial Measuring System flight patterns. These all combined to make for a dynamic and non-textbook situation. In addition, the data challenges of the multiple and on-going releases, and integration with the Japanese government to provide valid aerial radiological survey products that both military and civilian customers could use to make informed decisions, was extremely complicated. The Aerial Measuring System Fukushima response provided insight in addressing these challenges and gave way to an opportunity for the expansion of the Aerial Measuring System’s mission beyond the borders of the US.

  12. Postural control in man: the phylogenetic perspective.

    PubMed

    Gramsbergen, Albert

    2005-01-01

    Erect posture in man is a recent affordance from an evolutionary perspective. About eight million years ago, the stock from which modern humans derived split off from the ape family, and from around sixty-thousand years ago, modern man developed. Upright gait and manipulations while standing pose intricate cybernetic problems for postural control. The trunk, having an older evolutionary history than the extremities, is innervated by medially descending motor systems and extremity muscles by the more recent, laterally descending systems. Movements obviously require concerted actions from both systems. Research in rats has demonstrated the interdependencies between postural control and the development of fluent walking. Only 15 days after birth, adult-like fluent locomotion emerges and is critically dependent upon postural development. Vesttibular deprivation induces a retardation in postural development and, consequently, a retarded development of adult-like locomotion. The cerebellum obviously has an important role in mutual adjustments in postural control and extremity movements, or, in coupling the phylogenetic older and newer structures. In the human, the cerebellum develops partly after birth and therefore is vulnerable to adverse perinatal influences. Such vulnerability seems to justify focusing our scientific research efforts onto the development of this structure. PMID:16097476

  13. Aerial thermography for energy conservation

    NASA Technical Reports Server (NTRS)

    Jack, J. R.

    1978-01-01

    Thermal infrared scanning from an aircraft is a convenient and commercially available means for determining relative rates of energy loss from building roofs. The need to conserve energy as fuel costs makes the mass survey capability of aerial thermography an attractive adjunct to community energy awareness programs. Background information on principles of aerial thermography is presented. Thermal infrared scanning systems, flight and environmental requirements for data acquisition, preparation of thermographs for display, major users and suppliers of thermography, and suggested specifications for obtaining aerial scanning services were reviewed.

  14. Gravitational Effects upon Locomotion Posture

    NASA Technical Reports Server (NTRS)

    DeWitt, John K.; Bentley, Jason R.; Edwards, W. Brent; Perusek, Gail P.; Samorezov, Sergey

    2008-01-01

    Researchers use actual microgravity (AM) during parabolic flight and simulated microgravity (SM) obtained with horizontal suspension analogs to better understand the effect of gravity upon gait. In both environments, the gravitational force is replaced by an external load (EL) that returns the subject to the treadmill. However, when compared to normal gravity (N), researchers consistently find reduced ground reaction forces (GRF) and subtle kinematic differences (Schaffner et al., 2005). On the International Space Station, the EL is applied by elastic bungees attached to a waist and shoulder harness. While bungees can provide EL approaching body weight (BW), their force-length characteristics coupled with vertical oscillations of the body during gait result in a variable load. However, during locomotion in N, the EL is consistently equal to 100% body weight. Comparisons between AM and N have shown that during running, GRF are decreased in AM (Schaffner et al, 2005). Kinematic evaluations in the past have focussed on joint range of motion rather than joint posture at specific instances of the gait cycle. The reduced GRF in microgravity may be a result of differing hip, knee, and ankle positions during contact. The purpose of this investigation was to compare joint angles of the lower extremities during walking and running in AM, SM, and N. We hypothesized that in AM and SM, joints would be more flexed at heel strike (HS), mid-stance (MS) and toe-off (TO) than in N.

  15. Influence of forward head posture on condylar position.

    PubMed

    Ohmure, H; Miyawaki, S; Nagata, J; Ikeda, K; Yamasaki, K; Al-Kalaly, A

    2008-11-01

    There are several reports suggesting that forward head posture is associated with temporomandibular disorders and restraint of mandibular growth, possibly due to mandibular displacement posteriorly. However, there have been few reports in which the condylar position was examined in forward head posture. The purpose of this study was to test the hypothesis that the condyle moves posteriorly in the forward head posture. The condylar position and electromyography from the masseter, temporal and digastric muscles were recorded on 15 healthy male adults at mandibular rest position in the natural head posture and deliberate forward head posture. The condylar position in the deliberate forward head posture was significantly more posterior than that in the natural head posture. The activity of the masseter and digastric muscles in the deliberate forward head posture was slightly increased. These results suggest that the condyle moves posteriorly in subjects with forward head posture. PMID:18808377

  16. Anatomy and histochemistry of hindlimb flight posture in birds. I. The extended hindlimb posture of shorebirds.

    PubMed

    McFarland, Joshua C; Meyers, Ron A

    2008-08-01

    Birds utilize one of two hindlimb postures during flight: an extended posture (with the hip and knee joints flexed, while the ankle joint is extended caudally) or a flexed posture (with the hip, knee, and ankle joints flexed beneath the body). American Avocets (Recurvirostra americana) and Black-necked Stilts (Himantopus mexicanus) extend their legs caudally during flight and support them for extended periods. Slow tonic and slow twitch muscle fibers are typically found in muscles functioning in postural support due to the fatigue resistance of these fibers. We hypothesized that a set of small muscles composed of high percentages of slow fibers and thus dedicated to postural support would function in securing the legs in the extended posture during flight. This study examined the anatomy and histochemical profile of eleven hindlimb muscles to gain insight into their functional roles during flight. Contrary to our hypothesis, all muscles possessed both fast twitch and slow twitch or slow tonic fibers. We believe this finding is due to the versatility of dynamic and postural functions the leg muscles must facilitate, including standing, walking, running, swimming, and hindlimb support during flight. Whether birds use an extended or flexed hindlimb flight posture may be related to the aerodynamic effect of leg position or may reflect evolutionary history. PMID:18506762

  17. Modeling aerial refueling operations

    NASA Astrophysics Data System (ADS)

    McCoy, Allen B., III

    Aerial Refueling (AR) is the act of offloading fuel from one aircraft (the tanker) to another aircraft (the receiver) in mid flight. Meetings between tanker and receiver aircraft are referred to as AR events and are scheduled to: escort one or more receivers across a large body of water; refuel one or more receivers; or train receiver pilots, tanker pilots, and boom operators. In order to efficiently execute the Aerial Refueling Mission, the Air Mobility Command (AMC) of the United States Air Force (USAF) depends on computer models to help it make tanker basing decisions, plan tanker sorties, schedule aircraft, develop new organizational doctrines, and influence policy. We have worked on three projects that have helped AMC improve its modeling and decision making capabilities. Optimal Flight Planning. Currently Air Mobility simulation and optimization software packages depend on algorithms which iterate over three dimensional fuel flow tables to compute aircraft fuel consumption under changing flight conditions. When a high degree of fidelity is required, these algorithms use a large amount of memory and CPU time. We have modeled the rate of aircraft fuel consumption with respect to AC GrossWeight, Altitude and Airspeed. When implemented, this formula will decrease the amount of memory and CPU time needed to compute sortie fuel costs and cargo capacity values. We have also shown how this formula can be used in optimal control problems to find minimum costs flight plans. Tanker Basing Demand Mismatch Index. Since 1992, AMC has relied on a Tanker Basing/AR Demand Mismatch Index which aggregates tanker capacity and AR demand data into six regions. This index was criticized because there were large gradients along regional boundaries. Meanwhile tankers frequently cross regional boundaries to satisfy the demand for AR support. In response we developed continuous functions to score locations with respect to their proximity to demand for AR support as well as their

  18. Postural control at the human wrist

    PubMed Central

    Chew, John Z Z; Gandevia, Simon C; Fitzpatrick, Richard C

    2008-01-01

    In our movements and posture, we always act against a physical load. A key property of any load is its elastic stiffness (K), which describes how the force required to hold it must change with position. Here we examine how load stiffness affects the ability to maintain a stable posture at the wrist. Loads having positive (like a spring) and negative stiffness (like an inverted pendulum) were created by varying the position of weights on multiarm rigid pendulum. Subjects (n = 9) held 15 loads (K = ± 0.04, ± 0.01 and 0 N m deg−1 at mean torques of 0.2, 0.4 and 0.6 N m) still for 60 s. Residual wrist movement (sway) increased with mean torque and increased as stiffness became more negative. Large effects of load stiffness were seen at low frequencies (< 1.5 Hz) but not at higher frequencies that reflect load resonance and reflex activity. Subjects accurately perceived their postural sway while holding the loads but measured psychophysical thresholds showed that load stiffness was not perceived. We conclude that load stiffness, independent of force levels, affects the ability to control a load and that the postural control process relies on perception and volitional tracking rather than more automatic reflex pathways. Despite an awareness of their postural errors, we see no evidence for adaptation of postural control processes to compensate for changes in load properties. This is unlike the adaptation of feedforward control processes that produce targeted volitional movements when load properties are altered. We propose that postural control and movement control are fundamentally different neural processes. PMID:18187473

  19. Reliability of photographic posture analysis of adolescents

    PubMed Central

    Hazar, Zeynep; Karabicak, Gul Oznur; Tiftikci, Ugur

    2015-01-01

    [Purpose] Postural problems of adolescents needs to be evaluated accurately because they may lead to greater problems in the musculoskeletal system as they develop. Although photographic posture analysis has been frequently used, more simple and accessible methods are still needed. The purpose of this study was to investigate the inter- and intra-rater reliability of photographic posture analysis using MB-ruler software. [Subjects and Methods] Subjects were 30 adolescents (15 girls and 15 boys, mean age: 16.4±0.4 years, mean height 166.3±6.7 cm, mean weight 63.8±15.1 kg) and photographs of their habitual standing posture photographs were taken in the sagittal plane. For the evaluation of postural angles, reflective markers were placed on anatomical landmarks. For angular measurements, MB-ruler (Markus Bader- MB Software Solutions, triangular screen ruler) was used. Photographic evaluations were performed by two observers with a repetition after a week. Test-retest and inter-rater reliability evaluations were calculated using intra-class correlation coefficients (ICC). [Results] Inter-rater (ICC>0.972) and test-retest (ICC>0.774) reliability were found to be in the range of acceptable to excellent. [Conclusion] Reference angles for postural evaluation were found to be reliable and repeatable. The present method was found to be an easy and non-invasive method and it may be utilized by researchers who are in search of an alternative method for photographic postural assessments. PMID:26644658

  20. Modelling socio-metabolic transitions: The historical take-off, the acceleration of fossil fuel use, and the 1970s oil price shock - the first trigger of a future decline?

    NASA Astrophysics Data System (ADS)

    Wiedenhofer, Dominik; Rovenskaya, Elena; Krausmann, Fridolin; Haas, Willi; Fischer-Kowalski, Marina

    2013-04-01

    By talking about socio-metabolic transitions, we talk about changes in the energy base of socio-economic systems, leading to fundamental changes in social and environmental relations. This refers to the historical shift from a biomass-based (agrarian) economy to a fossil fuel based (industrial) economy just as much as to a future shift from fossil fuels to renewable energy carriers. In our presentation, • We will first show that this pattern of transition can be identified for most high income industrial countries: the later the transition started, the faster it proceeded, and the turning point to stabilization of metabolic rates in all of them happened in the early 1970ies. Due to the inherent non-linearity of this process, two approaches will be aplied to estimate parameters for the starting point, transition speed and saturation level: firstly a combination of an expontential and a generalized logistic function and secondly a Gompertz function. For both an iterative test procedure is applied to find the global minimum of the residual error for the whole function and all its parameters. This theory-based approach allows us to apply a robust methodology across all cases, thereby yielding results which can be generalized. • Next, we will show that this was not just a "historical" socio-ecological transition, however. Currently, a substantial number of countries comprising more than half of the world's population are following a similar transitional pathway at an ever accelerating pace. Based on empirical data on physical resource use and the above sketched methodology, we can show that these so-called emerging economies are currently in the take-off or acceleration phase of the very same transition. • Apart from these "endogenous" processes of socio-metabolic transition, we will investigate the effect of external shocks and their impact on the dynamics of energy and materials use. The first such shock we will explore is the oil crisis of 1972 that possibly

  1. Scapular Bracing and Alteration of Posture and Muscle Activity in Overhead Athletes With Poor Posture

    PubMed Central

    Cole, Ashley K; McGrath, Melanie L; Harrington, Shana E; Padua, Darin A; Rucinski, Terri J; Prentice, William E

    2013-01-01

    Context Overhead athletes commonly have poor posture. Commercial braces are used to improve posture and function, but few researchers have examined the effects of shoulder or scapular bracing on posture and scapular muscle activity. Objective To examine whether a scapular stabilization brace acutely alters posture and scapular muscle activity in healthy overhead athletes with forward-head, rounded-shoulder posture (FHRSP). Design Randomized controlled clinical trial. Setting Applied biomechanics laboratory. Patients or Other Participants Thirty-eight healthy overhead athletes with FHRSP. Intervention(s) Participants were assigned randomly to 2 groups: compression shirt with no strap tension (S) and compression shirt with the straps fully tensioned (S + T). Posture was measured using lateral-view photography with retroreflective markers. Electromyography (EMG) of the upper trapezius (UT), middle trapezius (MT), lower trapezius (LT), and serratus anterior (SA) in the dominant upper extremity was measured during 4 exercises (scapular punches, W's, Y's, T's) and 2 glenohumeral motions (forward flexion, shoulder extension). Posture and exercise EMG measurements were taken with and without the brace applied. Main Outcome Measure(s) Head and shoulder angles were measured from lateral-view digital photographs. Normalized surface EMG was used to assess mean muscle activation of the UT, MT, LT, and SA. Results Application of the brace decreased forward shoulder angle in the S + T condition. Brace application also caused a small increase in LT EMG during forward flexion and Y's and a small decrease in UT and MT EMG during shoulder extension. Brace application in the S + T group decreased UT EMG during W's, whereas UT EMG increased during W's in the S group. Conclusions Application of the scapular brace improved shoulder posture and scapular muscle activity, but EMG changes were highly variable. Use of a scapular brace might improve shoulder posture and muscle activity in

  2. Postural stability in children with hemiplegia estimated for three postural conditions: standing, sitting and kneeling.

    PubMed

    Szopa, Andrzej; Domagalska-Szopa, Małgorzata

    2015-04-01

    Postural control deficit is one of the most important problems in children with cerebral palsy (CP). The purpose of the presented study was to compare the effects of body posture asymmetry alone (i.e., in children with mild scoliosis) with the effects of body posture impairment (i.e., in children with hemiplegia) on postural stability. Forty-five outpatients with hemiplegia and 51 children with mild scoliosis were assessed using a posturography device. The examination comprised two parts: (1) analysis of the static load distribution; and (2) a posturographic test (CoP measurements) conducted in three postural conditions: standing, sitting and kneeling. Based on the asymmetry index of the unaffected/affected body sides while standing, the children with hemiplegia were divided into two different postural patterns: a pro-gravitational postural pattern (PGPP) and an anti-gravitational postural pattern (AGPP) (Domagalska-Szopa & Szopa (2013). BioMed Research International, 2013, 462094; (2014). Therapeutics and Clinical Risk Management, 10, 113). The group of children with mild scoliosis, considered as a standard for static body weight distribution, was used as the reference group. The results of present study only partially confirmed that children with hemiplegia have increased postural instability. Strong weight distribution asymmetry was found in children with an AGPP, which induced larger lateral-medial CoP displacements compared with children with scoliosis. In children with hemiplegia, distinguishing between their postural patterns may be useful to improve the guidelines for early therapy children with an AGPP before abnormal patterns of weight-bearing asymmetry are fully established. PMID:25677032

  3. Postural sway following cryotherapy in healthy adults.

    PubMed

    Fukuchi, Claudiane A; Duarte, Marcos; Stefanyshyn, Darren J

    2014-01-01

    In light of the wide use of cryotherapy and its potential negative effects on postural stability, little is known about how postural sway is affected, particularly when the whole lower limb is immersed. The purpose of this study was to analyze the influence of cryotherapy on postural sway in healthy males. Twenty-six subjects were randomly assigned into two intervention groups: control (tepid water at ∼26°C) or ice (cold water at ∼11°C). Postural sway was measured through the center of pressure (COP) position while they stood on a force plate during bipedal (70 s) and unipedal (40 s) conditions before and after the subjects were immersed in a water tub up to the umbilical level for 20 min. COP standard deviation (SD) and COP velocity were analyzed in the anterior-posterior (AP) and medial-lateral (ML) directions. Statistical analysis showed that in the bipedal condition cryotherapy increased the COP SD and COP velocity in the ML direction. During the unipedal condition, a higher COP velocity in the AP and ML directions was also reported. Our findings indicate that cryotherapy by immersing the whole lower limb should be used with caution before engaging in challenging postural control activities. PMID:24631278

  4. Effect of absence of vision on posture.

    PubMed

    Alotaibi, Abdullah Z; Alghadir, Ahmad; Iqbal, Zaheen A; Anwer, Shahnawaz

    2016-04-01

    [Purpose] The visual system is one of the sensory systems that enables the body to assess and process information about the external environment. In the absence of vision, a blind person loses contact with the outside world and develops faulty motor patterns, which results in postural deficiencies. However, literature regarding the development of such deficiencies is limited. The aim of this study was to discuss the effect of absence of vision on posture, the possible biomechanics behind the resulting postural deficiencies, and strategies to correct and prevent them. [Subjects and Methods] Various electronic databases including PubMed, Medline, and Google scholar were examined using the words "body", "posture", "blind" and "absence of vision". References in the retrieved articles were also examined for cross-references. The search was limited to articles in the English language. [Results] A total of 74 papers were shortlisted for this review, most of which dated back to the 1950s and 60s. [Conclusion] Blind people exhibit consistent musculoskeletal deformities. Absence of vision leads to numerous abnormal sensory and motor interactions that often limit blind people in isolation. Rehabilitation of the blind is a multidisciplinary task. Specialists from different fields need to diagnose and treat the deficiencies of the blind together as a team. Before restoring the normal mechanics of posture and gait, the missing link with the external world should be reestablished. PMID:27190486

  5. Coupling of postural and manual tasks in expert performers.

    PubMed

    Amado, A C; Palmer, C J; Hamill, J; van Emmerik, R E A

    2016-04-01

    The purpose of this study was to investigate the integration of bimanual rhythmic movements and posture in expert marching percussionists. Participants (N=11) performed three rhythmic manual tasks [1:1, 2:3, and 2:3-F (2:3 rhythm played faster at a self-selected tempo)] in one of three postures: sitting, standing on one foot, and standing on two feet. Discrete relative phase, postural time-to-contact, and coherence analysis were used to analyze the performance of the manual task, postural control, and the integration between postural and manual performance. Across all three rhythms, discrete relative phase mean and variability results showed no effects of posture on rhythmic performance. The complexity of the manual task (1:1 vs. 2:3) had no effect on postural time-to-contact. However, increasing the tempo of the manual task (2:3 vs. 2:3-F) did result in a decreased postural time-to-contact in the two-footed posture. Coherence analysis revealed that the coupling between the postural and manual task significantly decreased as a function of postural difficulty (going from a two-footed to a one-footed posture) and rhythmic complexity (1:1 vs. 2:3). Taken together, these results demonstrate that expert marching percussionists systematically decouple postural and manual fluctuations in order to preserve the performance of the rhythmic movement task. PMID:26803676

  6. Correlation between Trunk Posture and Neck Reposition Sense among Subjects with Forward Head Neck Postures

    PubMed Central

    Lee, Han Suk; Chung, Hyung Kuk; Park, Sun Wook

    2015-01-01

    Objective. To assess the correlation of abnormal trunk postures and reposition sense of subjects with forward head neck posture (FHP). Methods. In all, postures of 41 subjects were evaluated and the FHP and trunk posture including shoulder, scapular level, pelvic side, and anterior tilting degrees were analyzed. We used the head repositioning accuracy (HRA) test to evaluate neck position senses of neck flexion, neck extension, neck right and left side flexion, and neck right and left rotation and calculated the root mean square error in trials for each subject. Spearman's rank correlation coefficients and regression analysis were used to assess the degree of correlation between the trunk posture and HRA value, and a significance level of α = 0.05 was considered. Results. There were significant correlations between the HRA value of right side neck flexion and pelvic side tilt angle (p < 0.05). If pelvic side tilting angle increases by 1 degree, right side neck flexion increased by 0.76 degrees (p = 0.026). However, there were no significant correlations between other neck motions and trunk postures. Conclusion. Verifying pelvic postures should be prioritized when movement is limited due to the vitiation of the proprioceptive sense of neck caused by FHP. PMID:26583125

  7. Prompting correct lifting posture using signs.

    PubMed

    Burt, C D; Henningsen, N; Consedine, N

    1999-08-01

    The use of a symbol to prompt the adoption of correct lifting posture was examined in three studies. Study 1 used an Appropriateness Test to evaluate nine symbols designed to encourage the adoption of correct lifting posture. Four symbols met the appropriateness criteria and were tested for comprehension in Study 2. Study 3 examined the effect of the best performing symbol from Study 2 in a field setting which involved subjects lifting a small box. Results indicate significant increases in the adoption of the use of correct lifting posture when the symbol was present compared to a control condition. The study also identified the placement of a lifting criterion symbol onto packaging as a useful technique for communicating safety information. PMID:10416848

  8. Low Cost Surveying Using AN Unmanned Aerial Vehicle

    NASA Astrophysics Data System (ADS)

    Pérez, M.; Agüera, F.; Carvajal, F.

    2013-08-01

    Traditional manned airborne surveys are usually expensive and the resolution of the acquired images is often limited. The main advantage of Unmanned Aerial Vehicle (UAV) system acting as a photogrammetric sensor platform over more traditional manned airborne system is the high flexibility that allows image acquisition from unconventional viewpoints, the low cost in comparison with classical aerial photogrammetry and the high resolution images obtained. Nowadays there is a necessity for surveying small areas and in these cases, it is not economical the use of normal large format aerial or metric cameras to acquire aerial photos, therefore, the use of UAV platforms can be very suitable. Also the large availability of digital cameras has strongly enhanced the capabilities of UAVs. The use of digital non metric cameras together with the UAV could be used for multiple applications such as aerial surveys, GIS, wildfire mapping, stability of landslides, crop monitoring, etc. The aim of this work was to develop a low cost and accurate methodology in the production of orthophotos and Digital Elevation Models (DEM). The study was conducted in the province of Almeria, south of Spain. The photogrammetric flight had an altitude of 50 m over ground, covering an area of 5.000 m2 approximately. The UAV used in this work was the md4-200, which is an electronic battery powered quadrocopter UAV developed by Microdrones GmbH, Germany. It had on-board a Pextax Optio A40 digital non metric camera with 12 Megapixels. It features a 3x optical zoom lens with a focal range covering angles of view equivalent to those of 37-111 mm lens in 35 mm format. The quadrocopter can be programmed to follow a route defined by several waypoints and actions and it has the ability for vertical take off and landing. Proper flight geometry during image acquisition is essential in order to minimize the number of photographs, avoid areas without a good coverage and make the overlaps homogeneous. The flight

  9. Simulating aerial gravitropism and posture control in plants: what has been done, what is missing

    NASA Astrophysics Data System (ADS)

    Coutand, Catherine; Pot, Guillaume; Bastien, R.; Badel, Eric; Moulia, Bruno

    The gravitropic response requires a process of perception of the signal and a motor process to actuate the movements. Different models have been developed, some focuses on the perception process and some focuses on the motor process. The kinematics of the gravitropic response will be first detailed to set the phenomenology of gravi- and auto-tropism. A model of perception (AC model) will be first presented to demonstrate that sensing inclination is not sufficient to control the gravitropic movement, and that proprioception is also involved. Then, “motor models” will be reviewed. In herbaceous plants, differential growth is the main motor. Modelling tropic movements with simulating elongation raises some difficulties that will be explained. In woody structures the main motor process is the differentiation of reaction wood via cambial growth. We will first present the simplest biomechanical model developed to simulate gravitropism and its limits will be pointed out. Then a more sophisticated model (TWIG) will be presented with a special focus on the importance of wood viscoelasticity and the wood maturation process and its regulation by a mechanosensing process. The presentation will end by a balance sheet of what is done and what is missing for a complete modelling of gravitropism and will present first results of a running project dedicating to get the data required to include phototropism in the actual models.

  10. Pseudodystonic Posture Secondary to Klippel–Feil Syndrome and Diastematomyelia

    PubMed Central

    Lopez-Vicchi, Martin; Da Prat, Gustavo; Gatto, Emilia Mabel

    2015-01-01

    Background Dystonic postures possess a great number of differential diagnoses. Phenomenology Shown We describe a pseudodystonic posture in a 61-year-old woman with skeletal and extra-skeletal abnormalities. Educational Value Klippel–Feil syndrome represents an unusual cause of pseudodystonic posture to be considered in the differential diagnosis of dystonia. PMID:27352284

  11. Postural Control in Children: Implications for Pediatric Practice

    ERIC Educational Resources Information Center

    Westcott, Sarah L.; Burtner, Patricia

    2004-01-01

    Based on a systems theory of motor control, reactive postural control (RPA) and anticipatory postural control (APA) in children are reviewed from several perspectives in order to develop an evidence-based intervention strategy for improving postural control in children with limitations in motor function. Research on development of postural…

  12. Development of the Coordination between Posture and Manual Control

    ERIC Educational Resources Information Center

    Haddad, Jeffrey M.; Claxton, Laura J.; Keen, Rachel; Berthier, Neil E.; Riccio, Gary E.; Hamill, Joseph; Van Emmerik, Richard E. A.

    2012-01-01

    Studies have suggested that proper postural control is essential for the development of reaching. However, little research has examined the development of the coordination between posture and manual control throughout childhood. We investigated the coordination between posture and manual control in children (7- and 10-year-olds) and adults during…

  13. Aerial camera auto focusing system

    NASA Astrophysics Data System (ADS)

    Wang, Xuan; Lan, Gongpu; Gao, Xiaodong; Liang, Wei

    2012-10-01

    Before the aerial photographic task, the cameras focusing work should be performed at first to compensate the defocus caused by the changes of the temperature, pressure etc. A new method of aerial camera auto focusing is proposed through traditional photoelectric self-collimation combined with image processing method. Firstly, the basic principles of optical self-collimation and image processing are introduced. Secondly, the limitations of the two are illustrated and the benefits of the new method are detailed. Then the basic principle, the system composition and the implementation of this new method are presented. Finally, the data collection platform is set up reasonably and the focus evaluation function curve is draw. The results showed that: the method can be used in the Aerial camera focusing field, adapt to the aviation equipment trends of miniaturization and lightweight .This paper is helpful to the further work of accurate and automatic focusing.

  14. Dynamics of aerial target pursuit

    NASA Astrophysics Data System (ADS)

    Pal, S.

    2015-12-01

    During pursuit and predation, aerial species engage in multitasking behavior that involve simultaneous target detection, tracking, decision-making, approach and capture. The mobility of the pursuer and the target in a three dimensional environment during predation makes the capture task highly complex. Many researchers have studied and analyzed prey capture dynamics in different aerial species such as insects and bats. This article focuses on reviewing the capture strategies adopted by these species while relying on different sensory variables (vision and acoustics) for navigation. In conclusion, the neural basis of these capture strategies and some applications of these strategies in bio-inspired navigation and control of engineered systems are discussed.

  15. AERIAL OF VEHICLE ASSEMBLY BUILDING & SURROUNDING AREA

    NASA Technical Reports Server (NTRS)

    1977-01-01

    AERIAL OF VEHICLE ASSEMBLY BUILDING & SURROUNDING AREA KSC-377C-0082.41 116-KSC-377C-82.41, P-15877, ARCHIVE-04151 Aerial view - Shuttle construction progress - VAB and Orbiter Processing Facilities - direction northwest.

  16. Assessing Postural Stability in the Concussed Athlete

    PubMed Central

    Ruhe, Alexander; Fejer, René; Gänsslen, Axel; Klein, Wolfgang

    2014-01-01

    Context: Postural stability assessment is included as part of the diagnostic and monitoring process for sports-related concussions. Particularly, the relatively simple Balance Error Scoring System (BESS) and more sophisticated force plate measures like the Sensory Organization Test (SOT) are suggested. Evidence Acquisition: Relevant studies were identified via the following electronic databases: PubMed, MEDLINE, EMBASE, Web of Science, ScienceDirect, and CINAHL (1980 to July 2013). Inclusion was based on the evaluation of postural sway or balance in concussed athletes of any age or sex and investigating the reliability or validity of the included tests. Study Design: Clinical review. Level of Evidence: Level 4 Results: Both the SOT and the BESS show moderate reliability, but a learning effect due to repetitive testing needs to be considered. Both tests indicate that postural stability returns to baseline by day 3 to 5 in most concussed athletes. While the BESS is a simple and valid method, it is sensitive to subjectivity in scoring and the learning effect. The SOT is very sensitive to even subtle changes in postural sway, and thus, more accurate than the BESS; however, it is a rather expensive method of balance testing. Conclusion: Both tests serve the purpose of monitoring balance performance in the concussed athlete; however, neither may serve as a stand-alone diagnostic or monitoring tool. Strength of Recommendation Taxonomy: B PMID:25177420

  17. Influence of musical groove on postural sway.

    PubMed

    Ross, Jessica M; Warlaumont, Anne S; Abney, Drew H; Rigoli, Lillian M; Balasubramaniam, Ramesh

    2016-03-01

    Timescales of postural fluctuation reflect underlying neuromuscular processes in balance control that are influenced by sensory information and the performance of concurrent cognitive and motor tasks. An open question is how postural fluctuations entrain to complex environmental rhythms, such as in music, which also vary on multiple timescales. Musical groove describes the property of music that encourages auditory-motor synchronization and is used to study voluntary motor entrainment to rhythmic sounds. The influence of groove on balance control mechanisms remains unexplored. We recorded fluctuations in center of pressure (CoP) of standing participants (N = 40) listening to low and high groove music and during quiet stance. We found an effect of musical groove on radial sway variability, with the least amount of variability in the high groove condition. In addition, we observed that groove influenced postural sway entrainment at various temporal scales. For example, with increasing levels of groove, we observed more entrainment to shorter, local timescale rhythmic musical occurrences. In contrast, we observed more entrainment to longer, global timescale features of the music, such as periodicity, with decreasing levels of groove. Finally, musical experience influenced the amount of postural variability and entrainment at local and global timescales. We conclude that groove in music and musical experience can influence the neural mechanisms that govern balance control, and discuss implications of our findings in terms of multiscale sensorimotor coupling. (PsycINFO Database Record PMID:26727019

  18. Wearable monitoring of seated spinal posture.

    PubMed

    Dunne, L E; Walsh, P; Hermann, S; Smyth, B; Caulfield, B

    2008-06-01

    This work describes the evaluation of a wearable plastic optical fiber (POF) sensor for monitoring seated spinal posture, as compared to a conventional expert visual analysis, and the development of a field-deployable posture monitoring system. A garment-integrated POF sensor was developed and tested on nine healthy subjects. Data from the wearable sensor were compared to data taken simultaneously from a marker-based motion capture system, for accuracy and reliability. Peak analysis of the resulting data showed a mean time error of 0.53 plusmn 0.8 s, and a mean value error of 0.64 plusmn 3.1 deg, which represents 14.5% of the average range of motion. Expert determination of transitional (good to bad) posture showed a variation of 20.9% of range of motion. These results indicate that the wearable sensor approximates the accuracy of expert visual analysis, and provides sufficient accuracy of measurement to reliably monitor seated spinal posture. PMID:23852756

  19. Can Smartwatches Replace Smartphones for Posture Tracking?

    PubMed Central

    Mortazavi, Bobak; Nemati, Ebrahim; VanderWall, Kristina; Flores-Rodriguez, Hector G.; Cai, Jun Yu Jacinta; Lucier, Jessica; Naeim, Arash; Sarrafzadeh, Majid

    2015-01-01

    This paper introduces a human posture tracking platform to identify the human postures of sitting, standing or lying down, based on a smartwatch. This work develops such a system as a proof-of-concept study to investigate a smartwatch’s ability to be used in future remote health monitoring systems and applications. This work validates the smartwatches’ ability to track the posture of users accurately in a laboratory setting while reducing the sampling rate to potentially improve battery life, the first steps in verifying that such a system would work in future clinical settings. The algorithm developed classifies the transitions between three posture states of sitting, standing and lying down, by identifying these transition movements, as well as other movements that might be mistaken for these transitions. The system is trained and developed on a Samsung Galaxy Gear smartwatch, and the algorithm was validated through a leave-one-subject-out cross-validation of 20 subjects. The system can identify the appropriate transitions at only 10 Hz with an F-score of 0.930, indicating its ability to effectively replace smart phones, if needed. PMID:26506354

  20. Can smartwatches replace smartphones for posture tracking?

    PubMed

    Mortazavi, Bobak; Nemati, Ebrahim; VanderWall, Kristina; Flores-Rodriguez, Hector G; Cai, Jun Yu Jacinta; Lucier, Jessica; Naeim, Arash; Sarrafzadeh, Majid

    2015-01-01

    This paper introduces a human posture tracking platform to identify the human postures of sitting, standing or lying down, based on a smartwatch. This work develops such a system as a proof-of-concept study to investigate a smartwatch's ability to be used in future remote health monitoring systems and applications. This work validates the smartwatches' ability to track the posture of users accurately in a laboratory setting while reducing the sampling rate to potentially improve battery life, the first steps in verifying that such a system would work in future clinical settings. The algorithm developed classifies the transitions between three posture states of sitting, standing and lying down, by identifying these transition movements, as well as other movements that might be mistaken for these transitions. The system is trained and developed on a Samsung Galaxy Gear smartwatch, and the algorithm was validated through a leave-one-subject-out cross-validation of 20 subjects. The system can identify the appropriate transitions at only 10 Hz with an F-score of 0.930, indicating its ability to effectively replace smart phones, if needed. PMID:26506354

  1. Effect of absence of vision on posture

    PubMed Central

    Alotaibi, Abdullah Z.; Alghadir, Ahmad; Iqbal, Zaheen A.; Anwer, Shahnawaz

    2016-01-01

    [Purpose] The visual system is one of the sensory systems that enables the body to assess and process information about the external environment. In the absence of vision, a blind person loses contact with the outside world and develops faulty motor patterns, which results in postural deficiencies. However, literature regarding the development of such deficiencies is limited. The aim of this study was to discuss the effect of absence of vision on posture, the possible biomechanics behind the resulting postural deficiencies, and strategies to correct and prevent them. [Subjects and Methods] Various electronic databases including PubMed, Medline, and Google scholar were examined using the words “body”, “posture”, “blind” and “absence of vision”. References in the retrieved articles were also examined for cross-references. The search was limited to articles in the English language. [Results] A total of 74 papers were shortlisted for this review, most of which dated back to the 1950s and 60s. [Conclusion] Blind people exhibit consistent musculoskeletal deformities. Absence of vision leads to numerous abnormal sensory and motor interactions that often limit blind people in isolation. Rehabilitation of the blind is a multidisciplinary task. Specialists from different fields need to diagnose and treat the deficiencies of the blind together as a team. Before restoring the normal mechanics of posture and gait, the missing link with the external world should be reestablished. PMID:27190486

  2. Cognitive load affects postural control in children.

    PubMed

    Schmid, Maurizio; Conforto, Silvia; Lopez, Luisa; D'Alessio, Tommaso

    2007-05-01

    Inferring relations between cognitive processes and postural control is a relatively topical challenge in developmental neurology. This study investigated the effect of a concurrent cognitive task on postural control in a sample of 50 nine-year-old children. Each subject completed two balance trials of 60 s, one with a concurrent cognitive task (cognitive load) and another with no cognitive load. The concurrent cognitive task consisted of mentally counting backwards in steps of 2. Twelve posturographic parameters (PPs) were extracted from the centre of pressure (CoP) trajectory obtained through a load cell force plate. Analysis of variance revealed significant differences in the majority of the extracted PPs. CoP was found to travel faster, farther, and with substantially different features demonstrating an overall broadening of the spectrum in the frequency domain. Nonlinear stability factors revealed significant differences when exposed to a concurrent cognitive task, showing an increase of instability in the intervention rate of the postural control system. By grouping children through selected items from Teachers Ratings and PANESS assessment, specific significant differences were also found both in time and frequency domain PPs, thus confirming the hypothesis of an interaction between cognitive processes (and their development), and postural control. PMID:17136524

  3. Body Posture Facilitates Retrieval of Autobiographical Memories

    ERIC Educational Resources Information Center

    Dijkstra, Katinka; Kaschak, Michael P.; Zwaan, Rolf A.

    2007-01-01

    We assessed potential facilitation of congruent body posture on access to and retention of autobiographical memories in younger and older adults. Response times were shorter when body positions during prompted retrieval of autobiographical events were similar to the body positions in the original events than when body position was incongruent.…

  4. Forearm Posture and Mobility in Quadrupedal Dinosaurs

    PubMed Central

    VanBuren, Collin S.; Bonnan, Matthew

    2013-01-01

    Quadrupedality evolved four independent times in dinosaurs; however, the constraints associated with these transitions in limb anatomy and function remain poorly understood, in particular the evolution of forearm posture and rotational ability (i.e., active pronation and supination). Results of previous qualitative studies are inconsistent, likely due to an inability to quantitatively assess the likelihood of their conclusions. We attempt to quantify antebrachial posture and mobility using the radius bone because its morphology is distinct between extant sprawled taxa with a limited active pronation ability and parasagittal taxa that have an enhanced ability to actively pronate the manus. We used a sliding semi-landmark, outline-based geometric morphometric approach of the proximal radial head and a measurement of the angle of curvature of the radius in a sample of 189 mammals, 49 dinosaurs, 35 squamates, 16 birds, and 5 crocodilians. Our results of radial head morphology showed that quadrupedal ceratopsians, bipedal non-hadrosaurid ornithopods, and theropods had limited pronation/supination ability, and sauropodomorphs have unique radial head morphology that likely allowed limited rotational ability. However, the curvature of the radius showed that no dinosaurian clade had the ability to cross the radius about the ulna, suggesting parallel antebrachial elements for all quadrupedal dinosaurs. We conclude that the bipedal origins of all quadrupedal dinosaur clades could have allowed for greater disparity in forelimb posture than previously appreciated, and future studies on dinosaur posture should not limit their classifications to the overly simplistic extant dichotomy. PMID:24058633

  5. Inertia sensor-based guidance system for upperlimb posture correction.

    PubMed

    Ding, Z Q; Luo, Z Q; Causo, A; Chen, I M; Yue, K X; Yeo, S H; Ling, K V

    2013-02-01

    Stroke rehabilitation is labor-intensive and time-consuming. To assist patients and therapists alike, we propose a wearable system that measures orientation and corrects arm posture using vibrotactile actuators. The system evaluates user posture with respect to a reference and gives feedback in the form of vibration patterns. Users correct their arm posture, one DOF at a time, by following a protocol starting from the shoulder up to the forearm. Five users evaluated the proposed system by replicating ten different postures. Experimental results demonstrated system robustness and showed that some postures were easier to mimic depending on their naturalness. PMID:21978912

  6. Methods of Postural Assessment Used for Sports Persons

    PubMed Central

    Singla, Deepika

    2014-01-01

    Occurrence of postural defects has become very common now-a-days not only in general population but also in sports persons. There are various methods which can be used to assess these postural defects. These methods have evolved over a period of many years. This paper is first of its kind to summarize the methods of postural assessment which have been used and which can be used for evaluation of postural abnormalities in sports persons such as the visual observation, plumbline, goniometry, photographic, radiographic, photogrammetric, flexiruler, electromagnetic tracking device etc. We recommend more and more postural evaluation studies to be done in future based on the photogrammetric method. PMID:24959470

  7. Posture and Texting: Effect on Balance in Young Adults.

    PubMed

    Nurwulan, Nurul Retno; Jiang, Bernard C; Iridiastadi, Hardianto

    2015-01-01

    Using a mobile phone while doing another activity is a common dual-task activity in our daily lives. This study examined the effect of texting on the postural stability of young adults. Twenty college students were asked to perform static and dynamic postural stability tasks. Traditional COP and multivariate multiscale entropy (MMSE) were used to assess the static postural stability and the Star Excursion Balance Test (SEBT) was used to assess the dynamic postural stability. Results showed that (1) texting impaired postural stability, (2) the complexity index did not change much although the task conditions changed, and (3) performing texting is perceived to be more difficult. PMID:26230323

  8. Posture and Texting: Effect on Balance in Young Adults

    PubMed Central

    Nurwulan, Nurul Retno; Jiang, Bernard C.; Iridiastadi, Hardianto

    2015-01-01

    Using a mobile phone while doing another activity is a common dual-task activity in our daily lives. This study examined the effect of texting on the postural stability of young adults. Twenty college students were asked to perform static and dynamic postural stability tasks. Traditional COP and multivariate multiscale entropy (MMSE) were used to assess the static postural stability and the Star Excursion Balance Test (SEBT) was used to assess the dynamic postural stability. Results showed that (1) texting impaired postural stability, (2) the complexity index did not change much although the task conditions changed, and (3) performing texting is perceived to be more difficult. PMID:26230323

  9. Design of a nonlinear robust controller for a complete unmanned aerial vehicle mission

    NASA Astrophysics Data System (ADS)

    Sadraey, Mohammad Hashem

    Unmanned Aerial Vehicle (UAV) flight control systems must be capable of delivering the required performance while handling nonlinearities and uncertainties in the vehicle model, the atmosphere, and ambient wind. These factors necessitate the development of nonlinear flight control system design methods that can handle large nonlinearities and uncertainties. Variable approaches to the linear control of UAVs have been discussed in the recent literature. However, the development of a nonlinear robust autopilot has not been addressed to any significant degree. The development of a nonlinear autopilot based on robust control methods will be discussed in this dissertation. In this design technique, the nonlinear UAV model is not linearized. The control law is designed using the Hinfinity technique. This dissertation presents the results of an exploratory study to examine robust autopilot nonlinear design methods for the UAV and compare this new approach with existing PID, LQR, and linear Hinfinity techniques. Since the method must then be verified, its flight simulation will be done using MATLAB/SIMULINK. Verification, validation and robustness tests are documented at the end of this dissertation. The airplane examined is called the Hawkeye. It was designed and built by KU students in the fall of 2004. It is a small, 14 foot wingspan, remotely controlled airplane made from composite materials with a maximum takeoff weight of 90 lbs. It will be used in the future as a small UAV for research programs at KU. The mission includes take-off, climb, cruise, a one and a half circle accomplished in a level turn, and a return back to its original airfield accomplished by cruising back, descending, and completing an approach and landing. After take-off, the airplane is required to climb to 1,000 ft altitude, and then it travels 5,000 ft over the ground into the target area. It will then take some photos of that target using its camera. The complete mission for the UAV lasts about

  10. 29 CFR 1926.453 - Aerial lifts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... lift, except in case of emergency. (x) Climbers shall not be worn while performing work from an aerial... 29 Labor 8 2010-07-01 2010-07-01 false Aerial lifts. 1926.453 Section 1926.453 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Scaffolds § 1926.453 Aerial lifts. (a)...

  11. Postural sway and perceived comfort in pointing tasks.

    PubMed

    Solnik, Stanislaw; Pazin, Nemanja; Coelho, Chase J; Rosenbaum, David A; Zatsiorsky, Vladimir M; Latash, Mark L

    2014-05-21

    In this study, we explored relations between indices of postural sway and perceived comfort during pointing postures performed by standing participants. The participants stood on a force plate, grasped a pointer with the dominant (right) hand, and pointed to targets located at four positions and at two distances from the body. We quantified postural sway over 60-s intervals at each pointing posture, and found no effects of target location or distance on postural sway indices. In contrast, comfort ratings correlated significantly with indices of one of the sway components, trembling. Our observations support the hypothesis that rambling and trembling sway components involve different neurophysiological mechanisms. They also suggest that subjective perception of comfort may be more important than the actual posture for postural sway. PMID:24686189

  12. Reconnaissance mapping from aerial photographs

    NASA Technical Reports Server (NTRS)

    Weeden, H. A.; Bolling, N. B. (Principal Investigator)

    1975-01-01

    The author has identified the following significant results. Engineering soil and geology maps were successfully made from Pennsylvania aerial photographs taken at scales from 1:4,800 to 1:60,000. The procedure involved a detailed study of a stereoscopic model while evaluating landform, drainage, erosion, color or gray tones, tone and texture patterns, vegetation, and cultural or land use patterns.

  13. Postural education and behavior among students in a city in southern Brazil: student postural education and behavior

    PubMed Central

    Fonseca, Cíntia Detsch; Cardoso dos Santos, Antônio; Candotti, Cláudia Tarragô; Noll, Matias; Luz, Anna Maria Hecker; Corso, Carlos Otávio

    2015-01-01

    [Purpose] The aim of the present study was to assess the knowledge of the spine and posture among adolescent female students and to determine if they had access to postural education in or outside school. [Subjects and Methods] This was an epidemiological survey of a representative sample of 495 female students aged 14 to 18 years attending a regular secondary school in São Leopoldo, RS, Brazil. Data were collected through a questionnaire. [Results] The results showed that 16.8% of teens did not know what a spine was, 8.3% had no knowledge of posture, and 61% reported receiving no posture education. Posture awareness was associated only with posture while using a computer, while having postural education class was not associated with any postural behavior. [Conclusion] The results showed that, although most students are familiar with the spine and posture, a sizable group is not, and over half had no postural education. These findings suggest that inclusion of postural education programs in schools should be encouraged in order to promote health and prevent diseases related to the spine. PMID:26504322

  14. Postural education and behavior among students in a city in southern Brazil: student postural education and behavior.

    PubMed

    Fonseca, Cíntia Detsch; Cardoso Dos Santos, Antônio; Candotti, Cláudia Tarragô; Noll, Matias; Luz, Anna Maria Hecker; Corso, Carlos Otávio

    2015-09-01

    [Purpose] The aim of the present study was to assess the knowledge of the spine and posture among adolescent female students and to determine if they had access to postural education in or outside school. [Subjects and Methods] This was an epidemiological survey of a representative sample of 495 female students aged 14 to 18 years attending a regular secondary school in São Leopoldo, RS, Brazil. Data were collected through a questionnaire. [Results] The results showed that 16.8% of teens did not know what a spine was, 8.3% had no knowledge of posture, and 61% reported receiving no posture education. Posture awareness was associated only with posture while using a computer, while having postural education class was not associated with any postural behavior. [Conclusion] The results showed that, although most students are familiar with the spine and posture, a sizable group is not, and over half had no postural education. These findings suggest that inclusion of postural education programs in schools should be encouraged in order to promote health and prevent diseases related to the spine. PMID:26504322

  15. Age-dependency of posture parameters in children and adolescents

    PubMed Central

    Ludwig, Oliver; Mazet, Carola; Mazet, Dirk; Hammes, Annette; Schmitt, Eduard

    2016-01-01

    [Purpose] Poor posture in children and adolescents is a well-known problem. Therefore, early detection of incorrect posture is important. Photometric posture analysis is a cost-efficient and easy method, but needs reliable reference values. As children’s posture changes as they grow, the assessment needs to be age-specific. This study aimed to investigate the development of both one-dimensional posture parameter (body inclination angle) and complex parameter (posture index) in different age groups (childhood to adolescence). [Subjects and Methods] The participants were 372 symptom-free children and adolescents (140 girls and 232 boys aged 6–17). Images of their habitual posture were obtained in the sagittal plane. High-contrast marker points and marker spheres were placed on anatomical landmarks. Based on the marker points, the body inclination angle (INC) and posture index (PI) were calculated using the Corpus concepts software. [Results] The INC angle significantly increased with age. The PI did not change significantly among the age groups. No significant differences between the corresponding age groups were found for PI and INC for both sexes. [Conclusion] When evaluating posture using the body inclination angle, the age of the subject needs to be considered. Posture assessment with an age-independent parameter may be more suitable. PMID:27313382

  16. Obesity Impact on the Attentional Cost for Controlling Posture

    PubMed Central

    Mignardot, Jean-Baptiste; Olivier, Isabelle; Promayon, Emmanuel; Nougier, Vincent

    2010-01-01

    Background This study investigated the effects of obesity on attentional resources allocated to postural control in seating and unipedal standing. Methods Ten non obese adults (BMI = 22.4±1.3, age = 42.4±15.1) and 10 obese adult patients (BMI = 35.2±2.8, age = 46.2±19.6) maintained postural stability on a force platform in two postural tasks (seated and unipedal). The two postural tasks were performed (1) alone and (2) in a dual-task paradigm in combination with an auditory reaction time task (RT). Performing the RT task together with the postural one was supposed to require some attentional resources that allowed estimating the attentional cost of postural control. 4 trials were performed in each condition for a total of 16 trials. Findings (1) Whereas seated non obese and obese patients exhibited similar centre of foot pressure oscillations (CoP), in the unipedal stance only obese patients strongly increased their CoP sway in comparison to controls. (2) Whatever the postural task, the additional RT task did not affect postural stability. (3) Seated, RT did not differ between the two groups. (4) RT strongly increased between the two postural conditions in the obese patients only, suggesting that body schema and the use of internal models was altered with obesity. Interpretation Obese patients needed more attentional resources to control postural stability during unipedal stance than non obese participants. This was not the case in a more simple posture such as seating. To reduce the risk of fall as indicated by the critical values of CoP displacement, obese patients must dedicate a strong large part of their attentional resources to postural control, to the detriment of non-postural events. Obese patients were not able to easily perform multitasking as healthy adults do, reflecting weakened psycho-motor abilities. PMID:21187914

  17. Postural awareness among dental students in Jizan, Saudi Arabia

    PubMed Central

    Kanaparthy, Aruna; Kanaparthy, Rosaiah; Boreak, Nezar

    2015-01-01

    Objective: The study was conducted to assess the postural awareness of dental students in Jizan, Saudi Arabia. Materials and Methods: Close-ended, self-administered questionnaires were used for data collection in the survey. The questionnaire was prepared by observing the positions of students working in the clinics and the common mistakes they make with regard to their postures. The questionnaires were distributed among the dental students who were present and reported to work in the clinics. Levels of postural awareness and the relationship between postural awareness and the degree of musculoskeletal disorder (MSD) among the students was evaluated. This study was carried out in the College of Dental Sciences and Hospital, Jizan. Statistical Analysis: The level of knowledge of postural awareness was evaluated and correlated with the presence or absence of the MSDs. Categorical variables were compared using Chi-square test. P values of less than 0.05 were considered statistically significant. Results: A total of 162 dental students from the age group of 20–25 years were included in the survey, of which 134 dentists responded (83%). When their postural awareness was evaluated, results showed that 89% of the students had poor-to-medium levels of postural awareness. The relation between postural awareness and prevalence of MSDs indicated that 75% of the students with poor awareness, 49% of the students with average awareness, and 40% of the students with good awareness have MSDs. The results were statistically significant (0.002127, which is <0.005) stating that better awareness about proper postures while working helps to minimize the risk of MSDs. Conclusion: Evaluation of levels of postural awareness showed that 21% of the students had poor postural awareness, 67% had average awareness, and 11% had good postural awareness. The analysis of results showed that those students with low-to-average postural awareness had significantly greater prevalence of MSDs. PMID

  18. Smart Rehabilitation Garment for posture monitoring.

    PubMed

    Wang, Q; Chen, W; Timmermans, A A A; Karachristos, C; Martens, J B; Markopoulos, P

    2015-08-01

    Posture monitoring and correction technologies can support prevention and treatment of spinal pain or can help detect and avoid compensatory movements during the neurological rehabilitation of upper extremities, which can be very important to ensure their effectiveness. We describe the design and development of Smart Rehabilitation Garment (SRG) a wearable system designed to support posture correction. The SRG combines a number of inertial measurement units (IMUs), controlled by an Arduino processor. It provides feedback with vibration on the garment, audible alarm signals and visual instruction through a Bluetooth connected smartphone. We discuss the placement of sensing modules, the garment design, the feedback design and the integration of smart textiles and wearable electronics which aimed at achieving wearability and ease of use. We report on the system's accuracy as compared to optical tracker method. PMID:26737595

  19. Modulation of ankle stiffness during postural sway.

    PubMed

    Lang, Christopher B; Kearney, Robert E

    2014-01-01

    Ankle stiffness is a nonlinear, time-varying system which contributes to the control of human upright stance. This study sought to examine the nature of the contribution of stiffness to postural control by determining how intrinsic and reflex stiffnesses varied with sway. Subjects were instructed to stand quietly on a bilateral electro-hydraulic actuator while perturbations were applied about the ankle. Subjects performed three types of trials: normal stance, forward lean, and backward lean. Position, torque, and EMGs from the tibialis anterior and triceps surae were recorded. Background torque, intrinsic stiffness and reflex stiffness were calculated for each perturbation. Intrinsic and reflex stiffnesses were heavily modulated by postural sway. Moreover, they were modulated in a complimentary manner; intrinsic stiffness was lowest when reflex gain was highest, and vice versa. These findings suggest that intrinsic stiffness is modulated simultaneously with reflex stiffness to optimize the control of balance. PMID:25570884

  20. Ice skating promotes postural control in children.

    PubMed

    Keller, M; Röttger, K; Taube, W

    2014-12-01

    High fall rates causing injury and enormous financial costs are reported for children. However, only few studies investigated the effects of balance training in children and these studies did not find enhanced balance performance in postural (transfer) tests. Consequently, it was previously speculated that classical balance training might not be stimulating enough for children to adequately perform these exercises. Therefore, the aim of this study is to evaluate the influence of ice skating as an alternative form of balance training. Volunteers of an intervention (n = 17; INT: 13.1 ± 0.4 years) and a control group (n = 13; CON: 13.2 ± 0.3 years) were tested before and after training in static and dynamic postural transfer tests. INT participated in eight sessions of ice skating during education lessons, whereas CON participated in normal physical education. Enhanced balance performance was observed in INT but not in CON when tested on an unstable free-swinging platform (P < 0.05) or when performing a functional reach test (P < 0.001). This is the first study showing significantly enhanced balance performance after ice skating in children. More importantly, participating children improved static and dynamic balance control in postural tasks that were not part of the training. PMID:24739083

  1. Lead effects on postural balance of children.

    PubMed Central

    Bhattacharya, A; Shukla, R; Bornschein, R L; Dietrich, K N; Keith, R

    1990-01-01

    The postural sway responses of 63 children with a mean age of 5.74 years were quantified with a Force Platform technique. The average maximum (max) blood lead (PbB) of these children during the first 5 years of life was 20.7 micrograms/dL (range 9.2 to 32.5). The backward stepwise regression analysis for sway area response during the eyes-closed, no-foam test with all the covariates and confounders and the PbB parameters showed a significant relationship with peak or max PbB during the second year of life. These results are consistent with our previous study with a smaller group of children. The data have been analyzed to provide some insight into the role of various afferent for the maintenance of postural balance. The results suggests a hypothesis that if the max PbB had caused some level of impairment in the functional capacities or interconnectivity of the vestibular and/or proprioception systems at 2 years of age, then it is reasonable to assume that the redundancy in the postural afferent systems would naturally adapt to rely more on the remaining intact afferent system (in this case, vision). PMID:2088753

  2. Fingertip contact influences human postural control

    NASA Technical Reports Server (NTRS)

    Jeka, J. J.; Lackner, J. R.

    1994-01-01

    Touch and pressure stimulation of the body surface can strongly influence apparent body orientation, as well as the maintenance of upright posture during quiet stance. In the present study, we investigated the relationship between postural sway and contact forces at the fingertip while subjects touched a rigid metal bar. Subjects were tested in the tandem Romberg stance with eyes open or closed under three conditions of fingertip contact: no contact, touch contact (< 0.98 N of force), and force contact (as much force as desired). Touch contact was as effective as force contact or sight of the surroundings in reducing postural sway when compared to the no contact, eyes closed condition. Body sway and fingertip forces were essentially in phase with force contact, suggesting that fingertip contact forces are physically counteracting body sway. Time delays between body sway and fingertip forces were much larger with light touch contact, suggesting that the fingertip is providing information that allows anticipatory innervation of musculature to reduce body sway. The results are related to observations on precision grip as well as the somatosensory, proprioceptive, and motor mechanisms involved in the reduction of body sway.

  3. Postural dynamics and habituation to seasickness.

    PubMed

    Tal, Dror; Bar, Ronen; Nachum, Zohar; Gil, Amnon; Shupak, Avi

    2010-07-26

    The computerized dynamic posturography (CDP) test examines the response pattern to simultaneous, multimodal sensory stimulation. The purpose of this prospective, controlled study was to investigate whether postural dynamics evaluated by CDP are related to seasickness severity and the process of habituation to sea conditions. Subjects included 74 naval personnel assigned to service aboard ship and 29 controls designated for shore-based positions. Study participants performed a baseline CDP test, and subsequent follow-up examinations 6 and 12 months after completion of their training. On those occasions they also completed a seasickness severity questionnaire. Longitudinal changes in postural parameters were examined, as well as a possible correlation between baseline CDP results and final seasickness severity scores. The results indicated longitudinal habituation to seasickness. Reduced scores were found for sensory organization sub-tests 3 and 5 in the first follow-up examination, reflecting increased weighting of visual and somatosensory input in the maintenance of balance. Scores in the second follow-up examination were above baseline values, indicating increased reliance on vestibular cues. These significant bimodal changes were found only in study subjects having the highest degree of habituation to seasickness. A significant decrease in motor response strength was found in parallel with increased habituation to seasickness. Baseline CDP results and postural control dynamics were not correlated with subjects' final seasickness severity score. These results suggest a potential role for CDP in monitoring the process of habituation to unusual motion conditions. PMID:20493235

  4. Trends in quantitative aerial thermography

    SciTech Connect

    Schott, J.R.; Wilkinson, E.P.

    1983-06-01

    Recent improvements in aerial thermographic techniques, particularly in achievable spatial resolution and noise equivalent temperature variation, have enabled the use of thermography in a more objective fashion. Interpretation of the information contained in thermograms has also been improved through the use of certain techniques accounting for roof material type (emissivity), background effects, and atmospheric variables. With current methods, roof surface temperature from aerial imagery can be measured to within 1.8/sup 0/F (1.0/sup 0/C) of the actual temperature. These advances in thermogram analysis have opened the door for potential direct measurement of rooftop heat-loss levels from thermogram data. Ultimately, it is felt that this type of information would make it feasible to direct intensive energy-conservation efforts toward a smaller population, where the need and cost benefits will be the greatest.

  5. Aerial Photographs and Satellite Images

    USGS Publications Warehouse

    U.S. Geological Survey

    1997-01-01

    Photographs and other images of the Earth taken from the air and from space show a great deal about the planet's landforms, vegetation, and resources. Aerial and satellite images, known as remotely sensed images, permit accurate mapping of land cover and make landscape features understandable on regional, continental, and even global scales. Transient phenomena, such as seasonal vegetation vigor and contaminant discharges, can be studied by comparing images acquired at different times. The U.S. Geological Survey (USGS), which began using aerial photographs for mapping in the 1930's, archives photographs from its mapping projects and from those of some other Federal agencies. In addition, many images from such space programs as Landsat, begun in 1972, are held by the USGS. Most satellite scenes can be obtained only in digital form for use in computer-based image processing and geographic information systems, but in some cases are also available as photographic products.

  6. Aerial robotic data acquisition system

    SciTech Connect

    Hofstetter, K.J.; Hayes, D.W.; Pendergast, M.M.; Corban, J.E.

    1993-12-31

    A small, unmanned aerial vehicle (UAV), equipped with sensors for physical and chemical measurements of remote environments, is described. A miniature helicopter airframe is used as a platform for sensor testing and development. The sensor output is integrated with the flight control system for real-time, interactive, data acquisition and analysis. Pre-programmed flight missions will be flown with several sensors to demonstrate the cost-effective surveillance capabilities of this new technology.

  7. Telemetry of Aerial Radiological Measurements

    SciTech Connect

    H. W. Clark, Jr.

    2002-10-01

    Telemetry has been added to National Nuclear Security Administration's (NNSA's) Aerial Measuring System (AMS) Incident Response aircraft to accelerate availability of aerial radiological mapping data. Rapid aerial radiological mapping is promptly performed by AMS Incident Response aircraft in the event of a major radiological dispersal. The AMS airplane flies the entire potentially affected area, plus a generous margin, to provide a quick look at the extent and severity of the event. The primary result of the AMS Incident Response over flight is a map of estimated exposure rate on the ground along the flight path. Formerly, it was necessary to wait for the airplane to land before the map could be seen. Now, while the flight is still in progress, data are relayed via satellite directly from the aircraft to an operations center, where they are displayed and disseminated. This permits more timely utilization of results by decision makers and redirection of the mission to optimize its value. The current telemetry capability can cover all of North America. Extension to a global capability is under consideration.

  8. Detecting altered postural control after cerebral concussion in athletes with normal postural stability

    PubMed Central

    Cavanaugh, J; Guskiewicz, K; Giuliani, C; Marshall, S; Mercer, V; Stergiou, N

    2005-01-01

    Objective: To determine if approximate entropy (ApEn), a regularity statistic from non-linear dynamics, could detect changes in postural control during quiet standing in athletes with normal postural stability after cerebral concussion. Methods: The study was a retrospective, case series analysis of centre of pressure (COP) data collected during the Sensory Organization Test (SOT) from NCAA Division I (USA) athletes prior to and within 48 h after injury. Subjects were 21 male and six female athletes from a variety of sports who sustained a cerebral concussion between 1997 and 2003. After injury, athletes displayed normal postural stability equivalent to preseason levels. For comparison, COP data also were collected from 15 male and 15 female healthy non-athletes on two occasions. ApEn values were calculated for COP anterior-posterior (AP) and medial-lateral (ML) time series. Results: Compared to healthy subjects, COP oscillations among athletes generally became more regular (lower ApEn value) after injury despite the absence of postural instability. For AP time series, declines in ApEn values were much larger in SOT conditions 1 and 2 (approximately three times as large as the standard error of the mean) than for all other conditions. For ML time series, ApEn values declined after injury in all sensory conditions (F1,55 = 6.36, p = 0.02). Conclusions: Athletes who demonstrated normal postural stability after concussion nonetheless displayed subtle changes in postural control. Changes in ApEn may have represented a clinically abnormal finding. ApEn analysis of COP oscillations may be a valuable supplement to existing concussion assessment protocols for athletes. PMID:16244188

  9. Measurement of lip posture and interaction between lip posture and resting face height.

    PubMed

    Yemm, R; El-Sharkawy, M; Stephens, C D

    1978-10-01

    A method for measurement of lip incompetence is described. Electromyographic techniques were used to obtain relaxation of the muscles of the lip and of a jaw elevator muscle. Standardized photographs were taken of the subject's profile, from which lip separation and face height were measured. Variation was found in successive measurements of lip posture, some of which appeared to depend upon mandibular posture. With the teeth in occlusion, lip separation was reduced. Active maintenance of lip contact by the subject was often associated with a reduction in lower face height, which may have been a direct consequence of the lip muscle activity, or of jaw elevator activity facilitating the lip closure. PMID:280639

  10. The dentist’s operating posture – ergonomic aspects

    PubMed Central

    Pîrvu, C; Pătraşcu, I; Pîrvu, D; Ionescu, C

    2014-01-01

    Abstract The practice of dentistry involves laborious high finesse dental preparations, precision and control in executions that require a particular attention, concentration and patience of the dentist and finally the dentist’s physical and mental resistance. The optimal therapeutic approach and the success of practice involve special working conditions for the dentist and his team in an ergonomic environment. The meaning of the posture in ergonomics is the manner in which different parts of the body are located and thus the reports are established between them in order to allow a special task execution. This article discusses the posture adopted by dentists when they work, beginning with the balanced posture and going to different variants of posture. The ideal posture of a dentist gives him, on the one hand the optimal working conditions (access, visibility and control in the mouth) and on the other hand, physical and psychological comfort throughout the execution of the clinical acts. Although the theme of dentist posture is treated with great care and often presented in the undergraduate courses and the continuing education courses on ergonomics in dentistry, many dentists do not know the subject well enough nor the theoretical issues and therefore nor the practical applicability. The risk and perspective of the musculoskeletal disorders related to unbalanced postures should determine the dentists take postural corrective actions and compensation measures in order to limit the negative effects of working in a bad posture. PMID:25184007

  11. The Effect of Training on Postural Control in Dyslexic Children

    PubMed Central

    Goulème, Nathalie; Gérard, Christophe-Loïc; Bucci, Maria Pia

    2015-01-01

    The aim of this study was to explore whether a short postural training period could affect postural stability in dyslexic children. Postural performances were evaluated using Multitest Equilibre from Framiral. Posture was recorded in three different viewing conditions (eyes open fixating a target, eyes closed and eyes open with perturbed vision) and in two different postural conditions (on stable and unstable support). Two groups of dyslexic children participated in the study, i.e. G1: 16 dyslexic participants (mean age 9.9 ± 0.3 years) who performed short postural training and G2: 16 dyslexic participants of similar ages (mean age 9.1 ± 0.3 years) who did not perform any short postural training. Findings showed that short postural training improved postural stability on unstable support surfaces with perturbed vision: indeed the surface, the mean velocity of CoP and the spectral power indices in both directions decreased significantly, and the cancelling time in the antero-posterior direction improved significantly. Such improvement could be due to brain plasticity, which allows better performance in sensory process and cerebellar integration. PMID:26162071

  12. Effect of Posture on Hip Angles and Moments during Gait

    PubMed Central

    Lewis, Cara L.; Sahrmann, Shirley A.

    2014-01-01

    Anterior hip pain is common in young, active adults. Clinically, we have noted that patients with anterior hip pain often walk in a swayback posture, and that their pain is reduced when the posture is corrected. The purpose of this study was to investigate a potential mechanism for the reduction in pain by testing the effect of posture on movement patterns and internal moments during gait in healthy subjects. Fifteen subjects were instructed to walk while maintaining three postures: 1) natural, 2) swayback, and 3) forward flexed. Kinematic and force data were collected using a motion capture system and a force plate. Walking in the swayback posture resulted in a higher peak hip extension angle, hip flexor moment and hip flexion angular impulse compared to natural posture. In contrast, walking in a forward flexed posture resulted in a decreased hip extension angle and decreased hip flexion angular impulse. Based on these results, walking in a swayback posture may result in increased forces required of the anterior hip structures, potentially contributing to anterior hip pain. This study provides a potential biomechanical mechanism for clinical observations that posture correction in patients with hip pain is beneficial. PMID:25262565

  13. Potentially risky postural behaviors during worksite keyboard use

    PubMed Central

    Baker, Nancy A.; Redfern, Mark

    2016-01-01

    Objective This study describes the frequency and distribution of potentially risky postural behaviors of keyboard users. Method Forty-three subjects’ keyboard postural behaviors were rated with the Keyboard – Personal Computer Style instrument (K-PeCS) while they worked at their own workstations. The frequency and distribution of keyboard postural behaviors, and the associations and differences between the right and left sides were assessed. Results Generally, each static body posture had a single criterion that occurred most frequently, (e.g. elbow flexion posture 80 – 120 degrees), while dynamic postures of the wrists and hands were distributed throughout their criteria. Right and left side postural behaviors were significantly associated for shoulder flexion, elbow flexion, hand displacement, wrist extension, forearm rotation, isolated 5th digit, MCP hyperextension, and wrist support use, and significantly different for hand displacement, isolated thumb, number of digits used, and MCP hyperextension. Conclusion Potentially problematic keyboard postural behaviors are common among keyboard users. Our results suggest that occupational therapists must systematically assess body, arm, wrist, and hand postures on both the right and left sides to be able to develop the most effective intervention strategies. PMID:19708467

  14. Effect of Different Insoles on Postural Balance: A Systematic Review

    PubMed Central

    Christovão, Thaluanna Calil Lourenço; Neto, Hugo Pasini; Grecco, Luanda André Collange; Ferreira, Luiz Alfredo Braun; Franco de Moura, Renata Calhes; Eliege de Souza, Maria; Franco de Oliveira, Luis Vicente; Oliveira, Claudia Santos

    2013-01-01

    [Purpose] The aim of the present study was to perform a systematic review of the literature on the effect of different insoles on postural balance. [Subjects and Methods] A systematic review was conducted of four databases. The papers retrieved were evaluated based on the following inclusion criteria: 1) design: controlled clinical trial; 2) intervention: insole; 3) outcome: change in static postural balance; and 4) year of publication: 2005 to 2012. [Results] Twelve controlled trials were found comparing the effects of different insoles on postural balance. The papers had methodological quality scores of 3 or 4 on the PEDro scale. [Conclusion] Insoles have benefits that favor better postural balance and control. PMID:24259792

  15. Investigation of compensatory postures with videofluoromanometry in dysphagia patients

    PubMed Central

    Solazzo, Antonio; Monaco, Luigi; Del Vecchio, Lucia; Tamburrini, Stefania; Iacobellis, Francesca; Berritto, Daniela; Pizza, Nunzia Luisa; Reginelli, Alfonso; Di Martino, Natale; Grassi, Roberto

    2012-01-01

    AIM: To investigate the effectiveness of head compensatory postures to ensure safe oropharyngeal transit. METHODS: A total of 321 dysphagia patients were enrolled and assessed with videofluoromanometry (VFM). The dysphagia patients were classified as follows: safe transit; penetration without aspiration; aspiration before, during or after swallowing; multiple aspirations and no transit. The patients with aspiration or no transit were tested with VFM to determine whether compensatory postures could correct their swallowing disorder. RESULTS: VFM revealed penetration without aspiration in 71 patients (22.1%); aspiration before swallowing in 17 patients (5.3%); aspiration during swallowing in 32 patients (10%); aspiration after swallowing in 21 patients (6.5%); multiple aspirations in six patients (1.9%); no transit in five patients (1.6%); and safe transit in 169 patients (52.6%). Compensatory postures guaranteed a safe transit in 66/75 (88%) patients with aspiration or no transit. A chin-down posture achieved a safe swallow in 42/75 (56%) patients, a head-turned posture in 19/75 (25.3%) and a hyperextended head posture in 5/75 (6.7%). The compensatory postures were not effective in 9/75 (12%) cases. CONCLUSION: VFM allows the speech-language the-rapist to choose the most effective compensatory posture without a trial-and-error process and check the effectiveness of the posture. PMID:22736921

  16. The role of central vision in posture: Postural sway adaptations in Stargardt patients.

    PubMed

    Agostini, Valentina; Sbrollini, Agnese; Cavallini, Chanda; Busso, Alessandra; Pignata, Giulia; Knaflitz, Marco

    2016-01-01

    The role of central and peripheral vision in the maintenance of upright stance is debated in literature. Stargardt disease causes visual deficits affecting the central field, but leaving unaltered a patient's peripheral vision. Hence, the study of this rare pathology gives the opportunity to selectively investigate the role of central vision in posture. Postural sway in quiet stance was analyzed in 10 Stargardt patients and 10 control subjects, in three different conditions: (1) eyes closed, (2) eyes open, gazing at a fixed target, and (3) eyes open, tracking a moving target. Stargardt patients outperformed controls in the condition with eyes closed, showing a reduced root mean square (RMS) of the medio-lateral COP displacement, while their performance was not significantly different from controls in the antero-posterior direction. There were no significant differences between patients and controls in open eyes conditions. These results suggest that Stargardt patients adapted to a different visual-somatosensory integration, relying less on vision, especially in the medio-lateral direction. Hence, the central vision seems to affect mostly the medio-lateral direction of postural sway. This finding supports the plausibility of the "functional sensitivity hypothesis", that assigns complementary roles to central and peripheral vision in the control of posture. PMID:26514831

  17. Evidence for energy savings from aerial running in the Svalbard rock ptarmigan (Lagopus muta hyperborea)

    PubMed Central

    Nudds, R. L.; Folkow, L. P.; Lees, J. J.; Tickle, P. G.; Stokkan, K.-A.; Codd, J. R.

    2011-01-01

    Svalbard rock ptarmigans were walked and run upon a treadmill and their energy expenditure measured using respirometry. The ptarmigan used three different gaits: a walking gait at slow speeds (less than or equal to 0.75 m s−1), grounded running at intermediate speeds (0.75 m s−1 < U < 1.67 m s−1) and aerial running at high speeds (greater than or equal to 1.67 m s−1). Changes of gait were associated with reductions in the gross cost of transport (COT; J kg−1 m−1), providing the first evidence for energy savings with gait change in a small crouched-postured vertebrate. In addition, for the first time (excluding humans) a decrease in absolute metabolic energy expenditure (rate of O2 consumption) in aerial running when compared with grounded running was identified. The COT versus U curve varies between species and the COT was cheaper during aerial running than grounded running, posing the question of why grounded running should be used at all. Existing explanations (e.g. stability during running over rocky terrain) amount to just so stories with no current evidence to support them. It may be that grounded running is just an artefact of treadmill studies. Research investigating the speeds used by animals in the field is sorely needed. PMID:21288943

  18. Posture support improves object individuation in infants.

    PubMed

    Woods, Rebecca J; Wilcox, Teresa

    2013-08-01

    A hierarchical progression in infants' ability to use surface features, such as color, as a basis for object individuation in the first year has been well established (Tremoulet, Leslie, & Hall, 2000; Wilcox, 1999). There is evidence, however, that infants' sensitivity to surface features can be increased through multisensory (i.e., visuohaptic) exploration of objects (Wilcox, Woods, Chapa, & McCurry, 2007). Three studies were conducted to investigate the effect of multisensory experience on infants' sensitivity to pattern information. Experiments 1 and 2 confirmed that 5.5- and 6.5-month-olds do not spontaneously use pattern differences to individuate objects and revealed that 6.5- but not 5.5-month-olds can be primed to attend to pattern differences if allowed multisensory experience with the objects prior to the individuation task. However, the 5.5-month-olds also had greater difficulty maintaining a self-sitting posture during the multisensory priming experience. In Experiment 3, 4.5- and 5.5-month-olds were given full postural support during the multisensory exploration period. In this situation, the 5.5-month-olds successfully individuated the objects, but even with full postural support, 4.5-month-old infants did not use the pattern differences to individuate the objects. These results demonstrate that multisensory priming is effective with infants as young as 5.5 months and extends multisensory priming to another surface feature, pattern. Furthermore, these results indicate that constraints are placed on the multisensory experience by the physical and motor development of the infant. PMID:23046431

  19. Postural Stability When Leaning from Perceived Upright

    NASA Technical Reports Server (NTRS)

    Vanya, Robert D.; Grounds, John F.; Wood, Scott J.

    2011-01-01

    The transition between quiet stance and gait requires the volitional movement of one?s center of mass (COM) toward a limit of stability (LOS). The goal of this study was to measure the effect of leaning from perceived upright on postural stability when voluntarily maintaining fixed stance positions and during perturbations of the support surface. The COM was derived from force plate data in 12 healthy subjects while standing with feet positioned so that lateral base of support was equal to foot length. For all conditions, arms were folded and subjects were instructed to lean without bending at the hips or lifting their feet. The LOS was determined during maximal voluntary leans with eyes open and closed. The COM was then displayed on a monitor located in front of the subject. Subjects were visually guided to lean toward a target position, maintain this position for 10s, return to upright, and then repeat the same targeted lean maneuver with eyes closed. Targets were randomly presented at 2? in 8 directions and between 2-6? in these same directions according to the asymmetric LOS. Subjects were then verbally guided to lean between 2? back and 4? forward prior to a perturbation of the support surface in either a forward or backward direction. The average LOS was 5.8? forward, 2.9? back, and 4.8? in left/right directions, with no significant difference between eyes open and closed. Center of pressure (COP) velocity increased as subjects maintained fixed stance positions farther from upright, with increased variability during eyes closed conditions. The time to stability and COP path length increased as subjects leaned opposite to the direction of the support surface perturbations. We conclude that postural stability is compromised as subjects lean away from perceived upright, except for perturbations that induce sway in the direction opposite the lean. The asymmetric LOS relative to perceived upright favors postural stability for COM movements in the forward direction.

  20. Postural reorganization induced by torso cutaneous covibration.

    PubMed

    Lee, Beom-Chan; Martin, Bernard J; Ho, Allison; Sienko, Kathleen H

    2013-05-01

    Cutaneous information from joints has been attributed proprioceptive properties similar to those of muscle spindles. This study aimed to assess whether vibration-induced changes in torso cutaneous information contribute to whole-body postural reorganization in humans. Ten healthy young adults stood in normal and Romberg stances with six vibrating actuators positioned on the torso in contact with the skin over the left and right external oblique, internal oblique, and erector spinae muscle locations at the L4/L5 vertebrae level. Vibrations around the torso were randomly applied at two locations simultaneously (covibration) or at all locations simultaneously. Kinematic analysis of the body segments indicated that covibration applied to the skin over the internal oblique muscles induced shifts of both the head and torso in the anterior direction (torso flexion) while the hips shifted in the posterior direction (ankle plantar flexion). Conversely, covibration applied to the skin over the erector spinae muscle locations produced opposite effects. However, covibration applied to the skin over the left internal oblique and left erector spinae, the right internal oblique and right erector spinae, or at all locations simultaneously did not induce any significant postural changes. In addition, the center of pressure position as measured by the force plate was unaffected by all covibration conditions tested. These results were independent of stance and suggest an integrated and coordinated reorganization of posture in response to vibration-induced changes in cutaneous information. In addition, combinations of vibrotactile stimuli over multiple locations exhibit directional summation properties in contrast to the individual responses we observed in our previous work. PMID:23637178

  1. A Spherical Aerial Terrestrial Robot

    NASA Astrophysics Data System (ADS)

    Dudley, Christopher J.

    This thesis focuses on the design of a novel, ultra-lightweight spherical aerial terrestrial robot (ATR). The ATR has the ability to fly through the air or roll on the ground, for applications that include search and rescue, mapping, surveillance, environmental sensing, and entertainment. The design centers around a micro-quadcopter encased in a lightweight spherical exoskeleton that can rotate about the quadcopter. The spherical exoskeleton offers agile ground locomotion while maintaining characteristics of a basic aerial robot in flying mode. A model of the system dynamics for both modes of locomotion is presented and utilized in simulations to generate potential trajectories for aerial and terrestrial locomotion. Details of the quadcopter and exoskeleton design and fabrication are discussed, including the robot's turning characteristic over ground and the spring-steel exoskeleton with carbon fiber axle. The capabilities of the ATR are experimentally tested and are in good agreement with model-simulated performance. An energy analysis is presented to validate the overall efficiency of the robot in both modes of locomotion. Experimentally-supported estimates show that the ATR can roll along the ground for over 12 minutes and cover the distance of 1.7 km, or it can fly for 4.82 minutes and travel 469 m, on a single 350 mAh battery. Compared to a traditional flying-only robot, the ATR traveling over the same distance in rolling mode is 2.63-times more efficient, and in flying mode the system is only 39 percent less efficient. Experimental results also demonstrate the ATR's transition from rolling to flying mode.

  2. Artificial Intelligence Software for Assessing Postural Stability

    NASA Technical Reports Server (NTRS)

    Lieberman, Erez; Forth, Katharine; Paloski, William

    2013-01-01

    A software package reads and analyzes pressure distributions from sensors mounted under a person's feet. Pressure data from sensors mounted in shoes, or in a platform, can be used to provide a description of postural stability (assessing competence to deficiency) and enables the determination of the person's present activity (running, walking, squatting, falling). This package has three parts: a preprocessing algorithm for reading input from pressure sensors; a Hidden Markov Model (HMM), which is used to determine the person's present activity and level of sensing-motor competence; and a suite of graphical algorithms, which allows visual representation of the person's activity and vestibular function over time.

  3. Evolution and ecology of directed aerial descent in arboreal ants.

    PubMed

    Yanoviak, Stephen P; Munk, Yonatan; Dudley, Robert

    2011-12-01

    Directed aerial descent (DAD) is used by a variety of arboreal animals to escape predators, to remain in the canopy, and to access resources. Here, we build upon the discovery of DAD in ants of tropical canopies by summarizing its known phylogenetic distribution among ant genera, and within both the subfamily Pseudomyrmecinae and the genus Cephalotes. DAD has multiple evolutionary origins in ants, occurring independently in numerous genera in the subfamilies Myrmicinae, Formicinae, and Pseudomyrmecinae. Ablation experiments and video recordings of ants in a vertical wind tunnel showed that DAD in Cephalotes atratus is achieved via postural changes, specifically orientation of the legs and gaster. The occurrence of DAD in Formicinae indicates that the presence of a postpetiole is not essential for the behavior. Evidence to date indicates that gliding behavior is accomplished by visual targeting mediated by the compound eyes, and is restricted to diurnally active ants that nest in trees. Occlusion of ocelli in Pseudomyrmex gracilis workers had no effect on their success or performance in gliding. Experimental assessment of the fate of ants that fall to the understory showed that ants landing in water are 15 times more likely to suffer lethal attacks than are ants landing in leaf litter. Variation in both the aerodynamic mechanisms and selective advantages of DAD merits further study given the broad taxonomic diversity of arboreal ants that engage in this intriguing form of flight. PMID:21562023

  4. Aerial Measuring System Technical Integration Annual Report 2002

    SciTech Connect

    Bechtel Nevada Remote Sensing Laboratory

    2003-06-01

    Fiscal Year 2002 is the second year of a five-year commitment by the U.S. Department of Energy, National Nuclear Security Administration (NNSA) to invest in development of new and state-of-the-art technologies for the Aerial Measuring Systems (AMS) project. In 2000, NNSA committed to two million dollars for AMS Technical Integration (TI) for each of five years. The tragedy of September 11, 2001, profoundly influenced the program. NNSA redirected people and funding resources at the Remote Sensing Laboratory (RSL) to more immediate needs. Funds intended for AMS TI were redirected to NNSA's new posture of leaning further forward throughout. AMS TI was brought to a complete halt on December 10, 2001. Then on April 30, 2002, NNSA Headquarters allowed the restart of AMS TI at the reduced level of $840,000. The year's events resulted in a slow beginning of several projects, some of which were resumed only a few weeks before the AMS TI Symposium held at RSL on July 30.

  5. Prevalence of Common Postural Disorders Among Academic Dental Staff

    PubMed Central

    Vakili, Leila; Halabchi, Farzin; Mansournia, Mohammad Ali; Khami, Mohammad Reza; Irandoost, Shahla; Alizadeh, Zahra

    2016-01-01

    Background Musculoskeletal disorders are common problems among dentists. These conditions may lead to inappropriate postures and impairment in physical and psychological function. On the other hand, poor postures and inappropriate ergonomic may result in a wide variety of musculoskeletal disorders. Objectives The aim of this study was to investigate the prevalence of common postural disorders of the spine and shoulder girdle among the dentists and possible correlations between demographic, anthropometric and occupational characteristics with these abnormal postures. Patients and Methods In a cross-sectional study, 96 dental staff including academic staff, residents and senior students of Tehran University of Medical Sciences was enrolled. Data were collected using a questionnaire and posture assessment tools such as plumb-line, checkerboard and flexible ruler. Data analysis was done with SPSS version 17. Results The prevalence of the forward head posture (FHP), rounded shoulder posture (RSP), scoliosis and hyperlordosis were reported in 85.5%, 68.8%, 18.8% and 17.3% of the participants, respectively. A significant correlation was found between gender and FHP (P = 0.04) and also scoliosis (P = 0.009). On the other hand, a significant correlation was seen between weight and hyperlordosis (P = 0.007). Conclusions Our study revealed a high prevalence of postural disorders especially FHP, RSP and scoliosis among Iranian dental staff. The female dentists were less susceptible to FHP and scoliosis. PMID:27625751

  6. Predictors of Postural Stability in Children with ADHD

    ERIC Educational Resources Information Center

    Ghanizadeh, Ahmad

    2011-01-01

    Objective: As children with ADHD who have more inattention problems are more frequently with fine motor problems, it is not clear whether postural balance problems are associated with different subtypes of ADHD. This study investigates the predictors of postural stability in children with ADHD considering the covariant factors of age, gender, and…

  7. The effects of prolonged exposure to weightlessness on postural equilibrium

    NASA Technical Reports Server (NTRS)

    Homick, J. L.; Reschke, M. F.; Miller, E. F., II

    1977-01-01

    A postflight postural equilibrium rail tests on spacecrews was used to prove a pronounced decrement in ability to maintain an upright posture after prolonged exposure to weightlessness. Support for the hypothesis that central neural reorganization occurs in response to environmental change is obtained when postflight decrease in stability on the rails and the time course for recovery are compared with preflight performance.

  8. An Intellectual Posture for Teacher Educators: Two Approaches.

    ERIC Educational Resources Information Center

    Parkay, Forrest W.

    An intellectually clear conceptual base upon which to formulate a study of teacher education is considered. To achieve this conceptual clarification, two intellectual postures are described: John Dewey's "intellectual method" and John Wilson's intellectual "way of working." Three interrelated dimensions of an intellectual posture are discussed:…

  9. Turning Configural Processing Upside Down: Part and Whole Body Postures

    ERIC Educational Resources Information Center

    Reed, Catherine L.; Stone, Valerie E.; Grubb, Jefferson D.; McGoldrick, John E.

    2006-01-01

    Like faces, body postures are susceptible to an inversion effect in untrained viewers. The inversion effect may be indicative of configural processing, but what kind of configural processing is used for the recognition of body postures must be specified. The information available in the body stimulus was manipulated. The presence and magnitude of…

  10. Postural Strategies in Prader-Willi and Down Syndrome Patients

    ERIC Educational Resources Information Center

    Cimolin, Veronica; Galli, Manuela; Grugni, Graziano; Vismara, Luca; Precilios, Helmer; Albertini, Giorgio; Rigoldi, Chiara; Capodaglio, Paolo

    2011-01-01

    Patients affected by Down (DS) and Prader-Willi syndrome (PWS) are characterised by some common clinical and functional features including gait disorders and reduced postural control. The aim of our study was to quantitatively compare postural control in adult PWS and DS. We studied 12 PWS and 19 DS adult patients matched for age, height, weight…

  11. Selection of wrist posture in conditions of motor ambiguity.

    PubMed

    Wood, Daniel K; Goodale, Melvyn A

    2011-02-01

    In our everyday motor interactions with objects, we often encounter situations where the features of an object are determinate (i.e., not perceptually ambiguous), but the mapping between those features and appropriate movement patterns is indeterminate, resulting in a lack of any clear preference for one posture over another. We call this indeterminacy in stimulus-response mapping 'motor ambiguity'. Here, we use a grasping task to investigate the decision mechanisms that mediate the basic behavior of selecting one wrist posture over another in conditions of motor ambiguity. Using one of two possible wrist postures, participants grasped a dowel that was presented at various orientations. At most orientations, there was a clear preference for one wrist posture over the other. Within a small range of orientations, however, participants were variable in their posture selection due to the fact that the dowel was ambiguous with respect to the hand posture it afforded. We observed longer reaction times (RT) during 'ambiguous' trials than during the 'unambiguous' trials. In two subsequent experiments, we explored the effects of foreknowledge and trial history on the selection of wrist posture. We found that foreknowledge led to shorter RT unless the previous trial involved selecting a posture in the ambiguous region, in which case foreknowledge gave no RT advantage. These results are discussed within the context of existing models of sensorimotor decision making. PMID:21152907

  12. Disruption of postural readaptation by inertial stimuli following space flight

    NASA Technical Reports Server (NTRS)

    Black, F. O.; Paloski, W. H.; Reschke, M. F.; Igarashi, M.; Guedry, F.; Anderson, D. J.

    1999-01-01

    Postural instability (relative to pre-flight) has been observed in all shuttle astronauts studied upon return from orbital missions. Postural stability was more closely examined in four shuttle astronaut subjects before and after an 8 day orbital mission. Results of the pre- and post-flight postural stability studies were compared with a larger (n = 34) study of astronauts returning from shuttle missions of similar duration. Results from both studies indicated that inadequate vestibular feedback was the most significant sensory deficit contributing to the postural instability observed post flight. For two of the four IML-1 astronauts, post-flight postural instability and rate of recovery toward their earth-normal performance matched the performance of the larger sample. However, post-flight postural control in one returning astronaut was substantially below mean performance. This individual, who was within normal limits with respect to postural control before the mission, indicated that recovery to pre-flight postural stability was also interrupted by a post-flight pitch plane rotation test. A similar, though less extreme departure from the mean recovery trajectory was present in another astronaut following the same post-flight rotation test. The pitch plane rotation stimuli included otolith stimuli in the form of both transient tangential and constant centripetal linear acceleration components. We inferred from these findings that adaptation on orbit and re-adaptation on earth involved a change in sensorimotor integration of vestibular signals most likely from the otolith organs.

  13. Predictor variables for forward scapular posture including posterior shoulder tightness.

    PubMed

    Lee, Ji-Hyun; Cynn, Heon-seock; Yi, Chung-Hwi; Kwon, Oh-yun; Yoon, Tae-Lim

    2015-04-01

    The purpose of this study was (1) to determine the relationships between the degree of forward scapular posture and the pectoralis minor index, the strength of the serratus anterior, the thoracic spine angle, and posterior shoulder tightness, and (2) to identify predictors of forward scapular posture, including posterior shoulder tightness. The study recruited eighteen subjects with forward scapular posture and objectively measured the acromion distance, the pectoralis minor index, and the strength of the serratus anterior muscle of each participant. The amount of glenohumeral horizontal adduction and internal rotation were evaluated to measure posterior shoulder tightness. There were high intra-rater reliabilities in all measurements. The measurement results showed a statistically strong negative correlation between the degree of forward scapular posture and the pectoralis minor index. They also revealed a moderate positive correlation between the degree of forward scapular posture and the thoracic spine angle and a moderate negative relationship between the degree of forward scapular posture and the amount of the glenohumeral horizontal adduction. A multiple regression analysis indicated that a total multiple regression model explained 93% of the amount of forward scapular posture. All predictor variables, including posterior shoulder tightness, should be considered while assessing, managing, and preventing forward scapular posture. PMID:25892380

  14. Crouched posture maximizes ground reaction forces generated by muscles.

    PubMed

    Hoang, Hoa X; Reinbolt, Jeffrey A

    2012-07-01

    Crouch gait decreases walking efficiency due to the increased knee and hip flexion during the stance phase of gait. Crouch gait is generally considered to be disadvantageous for children with cerebral palsy; however, a crouched posture may allow biomechanical advantages that lead some children to adopt a crouch gait. To investigate one possible advantage of crouch gait, a musculoskeletal model created in OpenSim was placed in 15 different postures from upright to severe crouch during initial, middle, and final stance of the gait cycle for a total of 45 different postures. A series of optimizations was performed for each posture to maximize transverse plane ground reaction forces in the eight compass directions by modifying muscle forces acting on the model. We compared the force profile areas across all postures. Larger force profile areas were allowed by postures from mild crouch (for initial stance) to crouch (for final stance). The overall ability to generate larger ground reaction force profiles represents a mechanical advantage of a crouched posture. This increase in muscle capacity while in a crouched posture may allow a patient to generate new movements to compensate for impairments associated with cerebral palsy, such as motor control deficits. PMID:22542242

  15. Effects of Dyslexia on Postural Control in Adults

    ERIC Educational Resources Information Center

    Patel, M.; Magnusson, M.; Lush, D.; Gomez, S.; Fransson, P. A.

    2010-01-01

    Dyslexia has been shown to affect postural control. The aim of the present study was to investigate the difference in postural stability measured as torque variance in an adult dyslexic group (n=14, determined using the Adult Dyslexia Checklist (ADCL) and nonsense word repetition test) and an adult non-dyslexic group (n=39) on a firm surface and…

  16. An Uninhabited Aerial Vehicle (UAV) Concept for Low-Altitude Geophysical Exploration in Antarctica

    NASA Astrophysics Data System (ADS)

    Raymond, C. A.; Behar, A. E.

    2004-05-01

    A concept for a small, agile UAV platform for conducting geophysical mapping in the IPY and beyond has been explored. We have developed a framework concept for community input and feedback based on a low-cost, autonomous vehicle with onboard high-precision inertial navigation that performs vertical take-off and landing (VTOL). The vehicle we have focused on is the GoldenEye-100, developed by Aurora Flight Sciences Corp. (www.aurora.aero), which can carry a lightweight payload and achieve a range of 300-500 km (roundtrip). The VTOL capability would potentially allow flights to be launched from the helicopter deck of an icebreaker, and would remove the logistical burden of ensuring a hazard-free runway on the ice. Vehicle operations are controlled using a portable ground station. A payload concept has also been developed, indicating that the vehicle could easily carry a lightweight, compact magnetometer, camera and laser altimeter. Instruments developed for space missions exist that would enable a high performance system to be carried within the ~10 kg payload envelope. A gravity measurement system and radar sounder are also considered. A capable UAV platform for geophysical mapping would complement the existing aerial research platforms in Antarctica and has the potential to accelerate the exploration and monitoring of critical but remote areas in a cost-effective manner.

  17. Portable ammonia-borane-based H2 power-pack for unmanned aerial vehicles

    NASA Astrophysics Data System (ADS)

    Seo, Jung-Eun; Kim, Yujong; Kim, Yongmin; Kim, Kibeom; Lee, Jin Hee; Lee, Dae Hyung; Kim, Yeongcheon; Shin, Seock Jae; Kim, Dong-Min; Kim, Sung-Yug; Kim, Taegyu; Yoon, Chang Won; Nam, Suk Woo

    2014-05-01

    An advanced ammonia borane (AB)-based H2 power-pack is designed to continually drive an unmanned aerial vehicle (UAV) for 57 min using a 200-We polymer electrolyte membrane fuel cell (PEMFC). In a flight test with the UAV platform integrated with the developed power-pack, pure hydrogen with an average flow rate of 3.8 L(H2) min-1 is generated by autothermal H2-release from AB with tetraethylene glycol dimethylether (T4EGDE) as a promoter. During take-off, a hybridized power management system (PMS) consisting of the fuel cell and an auxiliary lithium-ion battery supplies 500 We at full power simultaneously, while the fuel cell alone provides 150-200 We and further recharges the auxiliary battery upon cruising. Gaseous byproducts identified by in situ Fourier transform infrared (FT-IR) spectroscopy during AB dehydrogenation are sequestrated using a mixed absorbent in an H2 purification system. In addition, a real-time monitoring system is employed to determine the remaining filter capacity of the purifier at a ground control system for rapidly responding unpredictable circumstances during flight. Separate experiments are conducted to screen potential materials and methods for enhancing filter capacity in the current H2 refining system. A prospective reactor concept for long-term fuel cell applications is proposed based on the results.

  18. Conceptual Design of a Vertical Takeoff and Landing Unmanned Aerial Vehicle with 24-HR Endurance

    NASA Technical Reports Server (NTRS)

    Fredericks, William J.

    2010-01-01

    This paper describes a conceptual design study for a vertical takeoff and landing (VTOL) unmanned aerial vehicle (UAV) that is able to carry a 25-lb science payload for 24 hr and is able to land and take off at elevations as high as 15,000 ft without human intervention. In addition to the science payload, this vehicle must be able to carry a satellite communication system, and the vehicle must be able to be transported in a standard full-size pickup truck and assembled by only two operators. This project started with a brainstorming phase to devise possible vehicle configurations that might satisfy the requirements. A down select was performed to select a near-term solution and two advanced vehicle concepts that are better suited to the intent of the mission. Sensitivity analyses were also performed on the requirements and the technology levels to obtain a better understanding of the design space. This study found that within the study assumptions the mission is feasible; the selected concepts are recommended for further development.

  19. Astronomical Methods in Aerial Navigation

    NASA Technical Reports Server (NTRS)

    Beij, K Hilding

    1925-01-01

    The astronomical method of determining position is universally used in marine navigation and may also be of service in aerial navigation. The practical application of the method, however, must be modified and adapted to conform to the requirements of aviation. Much of this work of adaptation has already been accomplished, but being scattered through various technical journals in a number of languages, is not readily available. This report is for the purpose of collecting under one cover such previous work as appears to be of value to the aerial navigator, comparing instruments and methods, indicating the best practice, and suggesting future developments. The various methods of determining position and their application and value are outlined, and a brief resume of the theory of the astronomical method is given. Observation instruments are described in detail. A complete discussion of the reduction of observations follows, including a rapid method of finding position from the altitudes of two stars. Maps and map cases are briefly considered. A bibliography of the subject is appended.

  20. Postural Tachycardia Syndrome: Beyond Orthostatic Intolerance

    PubMed Central

    Garland, Emily M; Celedonio, Jorge E; Raj, Satish R

    2015-01-01

    Postural Tachycardia Syndrome (POTS) is a form of chronic orthostatic intolerance for which the hallmark physiological trait is an excessive increase in heart rate with assumption of upright posture. The orthostatic tachycardia occurs in the absence of orthostatic hypotension and is associated with a >6-month history of symptoms that are relieved by recumbence. The heart rate abnormality and orthostatic symptoms should not be caused by medications that impair autonomic regulation or by debilitating disorders that can cause tachycardia. POTS is a “final common pathway” for a number of overlapping pathophysiologies, including an autonomic neuropathy in the lower body, hypovolemia, elevated sympathetic tone, mast cell activation, deconditioning, and autoantibodies. Not only may patients be affected by more than one of these pathophysiologies, but also the phenotype of POTS has similarities to a number of other disorders, e.g., chronic fatigue syndrome, Ehlers-Danlos Syndrome, vasovagal syncope, and inappropriate sinus tachycardia. POTS can be treated with a combination of non-pharmacological approaches, a structured exercise training program, and often some pharmacological support. PMID:26198889

  1. Fitts’ Law in Early Postural Adjustments

    PubMed Central

    Bertucco, M.; Cesari, P.; Latash, M.L

    2012-01-01

    We tested a hypothesis that the classical relation between movement time and index of difficulty (ID) in quick pointing action (Fitts’ Law) reflects processes at the level of motor planning. Healthy subjects stood on a force platform and performed quick and accurate hand movements into targets of different size located at two distances. The movements were associated with early postural adjustments that are assumed to reflect motor planning processes. The short distance did not require trunk rotation, while the long distance did. As a result, movements over the long distance were associated with substantiual Coriolis forces. Movement kinematics and contact forces and moments recorded by the platform were studied. Movement time scaled with ID for both movements. However, the data could not be fitted with a single regression: Movements over the long distance had a larger intercept corresponding to movement times about 140 ms longer than movements over the shorter distance. The magnitude of postural adjustments prior to movement initiation scaled with ID for both short and long distances. Our results provide strong support for the hypothesis that Fitts’ Law emerges at the level of motor planning, not at the level of corrections of ongoing movements. They show that, during natural movements, changes in movement distance may lead to changes in the relation between movement time and ID, for example when the contribution of different body segments to the movement varies and when the action of Coriolis force may require an additional correction of the movement trajectory. PMID:23211560

  2. Emotion expression in body action and posture.

    PubMed

    Dael, Nele; Mortillaro, Marcello; Scherer, Klaus R

    2012-10-01

    Emotion communication research strongly focuses on the face and voice as expressive modalities, leaving the rest of the body relatively understudied. Contrary to the early assumption that body movement only indicates emotional intensity, recent studies have shown that body movement and posture also conveys emotion specific information. However, a deeper understanding of the underlying mechanisms is hampered by a lack of production studies informed by a theoretical framework. In this research we adopted the Body Action and Posture (BAP) coding system to examine the types and patterns of body movement that are employed by 10 professional actors to portray a set of 12 emotions. We investigated to what extent these expression patterns support explicit or implicit predictions from basic emotion theory, bidimensional theory, and componential appraisal theory. The overall results showed partial support for the different theoretical approaches. They revealed that several patterns of body movement systematically occur in portrayals of specific emotions, allowing emotion differentiation. Although a few emotions were prototypically expressed by one particular pattern, most emotions were variably expressed by multiple patterns, many of which can be explained as reflecting functional components of emotion such as modes of appraisal and action readiness. It is concluded that further work in this largely underdeveloped area should be guided by an appropriate theoretical framework to allow a more systematic design of experiments and clear hypothesis testing. PMID:22059517

  3. Postural Tachycardia Syndrome: Beyond Orthostatic Intolerance.

    PubMed

    Garland, Emily M; Celedonio, Jorge E; Raj, Satish R

    2015-09-01

    Postural tachycardia syndrome (POTS) is a form of chronic orthostatic intolerance for which the hallmark physiological trait is an excessive increase in heart rate with assumption of upright posture. The orthostatic tachycardia occurs in the absence of orthostatic hypotension and is associated with a >6-month history of symptoms that are relieved by recumbence. The heart rate abnormality and orthostatic symptoms should not be caused by medications that impair autonomic regulation or by debilitating disorders that can cause tachycardia. POTS is a "final common pathway" for a number of overlapping pathophysiologies, including an autonomic neuropathy in the lower body, hypovolemia, elevated sympathetic tone, mast cell activation, deconditioning, and autoantibodies. Not only may patients be affected by more than one of these pathophysiologies but also the phenotype of POTS has similarities to a number of other disorders, e.g., chronic fatigue syndrome, Ehlers-Danlos syndrome, vasovagal syncope, and inappropriate sinus tachycardia. POTS can be treated with a combination of non-pharmacological approaches, a structured exercise training program, and often some pharmacological support. PMID:26198889

  4. [Orthostatic postural tachycardia: study of 8 patients].

    PubMed

    Santiago Pérez, S; Ferrer Gila, T

    1998-02-01

    The occurrence of syncopal episodes is a very frequent event. In the absence of a structural systemic or cardiac disease, syncope is resulting of an anomalous cardiovascular response neurally mediated by the autonomic nervous system. It is the final common manifestation of different abnormal mechanisms and is frequently precipitated by orthostatism. Orthostatic intolerance syndrome refers to the development of symptoms during the upright posture that disappear in supine position. Tachycardia may be one of the clinical features of the syndrome. During orthostatic stress a hyperadrenergic response, with maintained increment of heart rate and associated symptoms, is developed. Changes in blood pressure may be diverse and in some cases hypotension and syncope occurs. Eight patients with symptoms of orthostatic intolerance who underwent autonomic evaluation and were diagnosed from postural tachycardia are presented. In all the cases an abnormal increment of heart rate during tilting was found and it was associated to hyperadrenergic symptoms. Evidence of restricted sympathetic impairment was observed in six cases with distal reduction of sudomotor function and abnormal adrenergic response during Valsalva manoeuvre. Symptoms disappeared or mostly subsided with pharmacological (amitriptyline in one case, phenobarbital in another one and non-cardioselective beta-blockers in six patients) and non-pharmacological treatment. In further examinations heart rate and blood pressure were normal. PMID:9541904

  5. 29 CFR 1926.453 - Aerial lifts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Aerial lifts. 1926.453 Section 1926.453 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Scaffolds § 1926.453 Aerial lifts. (a) General requirements. (1) Unless otherwise provided...

  6. A Classroom Simulation of Aerial Photography.

    ERIC Educational Resources Information Center

    Baker, Simon

    1981-01-01

    Explains how a simulation of aerial photography can help students in a college level beginning course on interpretation of aerial photography understand the interrelationships of the airplane, the camera, and the earth's surface. Procedures, objectives, equipment, and scale are discussed. (DB)

  7. BOREAS Level-0 ER-2 Aerial Photography

    NASA Technical Reports Server (NTRS)

    Newcomer, Jeffrey A.; Dominquez, Roseanne; Hall, Forrest G. (Editor)

    2000-01-01

    For BOReal Ecosystem-Atmosphere Study (BOREAS), the ER-2 and other aerial photography was collected to provide finely detailed and spatially extensive documentation of the condition of the primary study sites. The ER-2 aerial photography consists of color-IR transparencies collected during flights in 1994 and 1996 over the study areas.

  8. Barnacle Geese Achieve Significant Energetic Savings by Changing Posture

    PubMed Central

    Tickle, Peter G.; Nudds, Robert L.; Codd, Jonathan R.

    2012-01-01

    Here we report the resting metabolic rate in barnacle geese (Branta leucopsis) and provide evidence for the significant energetic effect of posture. Under laboratory conditions flow-through respirometry together with synchronous recording of behaviour enabled a calculation of how metabolic rate varies with posture. Our principal finding is that standing bipedally incurs a 25% increase in metabolic rate compared to birds sitting on the ground. In addition to the expected decrease in energy consumption of hindlimb postural muscles when sitting, we hypothesise that a change in breathing mechanics represents one potential mechanism for at least part of the observed difference in energetic cost. Due to the significant effect of posture, future studies of resting metabolic rates need to take into account and/or report differences in posture. PMID:23071672

  9. Adaptive planning of emergency aerial photogrammetric mission

    NASA Astrophysics Data System (ADS)

    Shen, Fuqiang; Zhu, Qing; Zhang, Junxiao; Miao, Shuangxi; Zhou, Xingxia; Cao, Zhenyu

    2015-12-01

    Aiming at the diversity of emergency aerial photogrammetric mission requirements, complex ground and air environmental constraints make the planning mission time-consuming. This paper presents a fast adaptation for the UAV aerial photogrammetric mission planning. First, Building emergency aerial UAVs mission the unified expression of UAVs model and mechanical model of performance parameters in the semantic space make the integrated expression of mission requirements and low altitude environment. Proposed match assessment method which based on resource and mission efficiency. Made the Adaptive match of UAV aerial resources and mission. According to the emergency aerial resource properties, considering complex air-ground environment and mission requirements constraints. Made accurate design of UAV route. Experimental results show, the method scientific and efficient, greatly enhanced the emergency response rate.

  10. Effect of Seated Trunk Posture on Eye Blink Startle and Subjective Experience: Comparing Flexion, Neutral Upright Posture, and Extension of Spine

    PubMed Central

    Ceunen, Erik; Zaman, Jonas; Vlaeyen, Johan W. S.; Dankaerts, Wim; Van Diest, Ilse

    2014-01-01

    Postures are known to be able to affect emotion and motivation. Much less is known about whether (affective) modulation of eye blink startle occurs following specific postures. The objective of the current study was to explore this. Participants in the present study were requested to assume three different sitting postures: with the spine flexed (slouched), neutral upright, and extended. Each posture was assumed for four minutes, and was followed by the administration of brief self-report questionnaires before proceeding to the next posture. The same series of postures and measures were repeated prior to ending the experiment. Results indicate that, relative to the other postures, the extended sitting posture was associated with an increased startle, was more unpleasant, arousing, had smaller levels of dominance, induced more discomfort, and was perceived as more difficult. The upright and flexed sitting postures differed in the level of self-reported positive affect, but not in eye blink startle amplitudes. PMID:24516664

  11. Correlation dimension estimates of human postural sway.

    PubMed

    Gurses, Senih; Celik, Huseyin

    2013-02-01

    Human postural sway during quiet standing demonstrates a complex structured dynamics, which has been studied by applying numerous methods, such as linear system identification methods, stochastic analysis, and nonlinear system dynamics tools. Although each of the methods applied revealed some particular features of the sway data none of them have succeeded to present a global picture of the quiet stance dynamics, which probably has both stochastic and deterministic properties. In this study we have started applying ergodic theory of dynamical systems to explore statistical characteristic of the sway dynamics observed in successive trials of a subject, different subjects in an age group, and finally different age groups constituted by children, adults, and elderly subjects. Five successive 180-s long trials were performed by each of 28 subjects in four age groups at quiet stance with eyes open. Stationary and ergodic signal characteristics of five successive center of pressure time series collected from a subject in antero-posterior direction (CoPx) were examined. 97% of the trials were found to be stationary by applying Run Test while children and elderly groups demonstrated significant nonstationary behavior. On the other hand 13 out of 24 subjects were found to be nonergodic. We expected to observe differences in complexity of CoPx dynamics due to aging (Farmer, Ott, & Yorke, 1983). However linear metrics such as standard deviation and Fourier spectra of CoPx signals did not show differences due to the age groups. Correlation dimension (Dk) estimates of stationary CoPx signals being an invariant measure of nonlinear system dynamics were computed by using the average displacement method (Eckmann & Ruelle, 1985). Postural dynamics was expanded in m-dimensional space through CoPx signal by introducing optimum time delays, τcritical. 112 out of 136 stationary CoPx signals for 24 stationary subjects converged to Dk estimates. Average of Dk estimates for children and

  12. Sensorimotor integration in human postural control

    NASA Technical Reports Server (NTRS)

    Peterka, R. J.

    2002-01-01

    It is generally accepted that human bipedal upright stance is achieved by feedback mechanisms that generate an appropriate corrective torque based on body-sway motion detected primarily by visual, vestibular, and proprioceptive sensory systems. Because orientation information from the various senses is not always available (eyes closed) or accurate (compliant support surface), the postural control system must somehow adjust to maintain stance in a wide variety of environmental conditions. This is the sensorimotor integration problem that we investigated by evoking anterior-posterior (AP) body sway using pseudorandom rotation of the visual surround and/or support surface (amplitudes 0.5-8 degrees ) in both normal subjects and subjects with severe bilateral vestibular loss (VL). AP rotation of body center-of-mass (COM) was measured in response to six conditions offering different combinations of available sensory information. Stimulus-response data were analyzed using spectral analysis to compute transfer functions and coherence functions over a frequency range from 0.017 to 2.23 Hz. Stimulus-response data were quite linear for any given condition and amplitude. However, overall behavior in normal subjects was nonlinear because gain decreased and phase functions sometimes changed with increasing stimulus amplitude. "Sensory channel reweighting" could account for this nonlinear behavior with subjects showing increasing reliance on vestibular cues as stimulus amplitudes increased. VL subjects could not perform this reweighting, and their stimulus-response behavior remained quite linear. Transfer function curve fits based on a simple feedback control model provided estimates of postural stiffness, damping, and feedback time delay. There were only small changes in these parameters with increasing visual stimulus amplitude. However, stiffness increased as much as 60% with increasing support surface amplitude. To maintain postural stability and avoid resonant behavior, an

  13. Newly Standing Infants Increase Postural Stability When Performing a Supra-Postural Task

    PubMed Central

    Claxton, Laura J.; Haddad, Jeffrey M.; Ponto, Katelyn; Ryu, Joong Hyun; Newcomer, Sean C.

    2013-01-01

    Independent stance is one of the most difficult motor milestones to achieve. Newly standing infants exhibit exaggerated body movements and can only stand for a brief amount of time. Given the difficult nature of bipedal stance, these unstable characteristics are slow to improve. However, we demonstrate that infants can increase their stability when engaged in a standing goal-directed task. Infants' balance was measured while standing and while standing and holding a visually attractive toy. When holding the toy, infants stood for a longer period of time, exhibited less body sway, and more mature postural dynamics. These results demonstrate that even with limited standing experience, infants can stabilize posture to facilitate performance of a concurrent task. PMID:23940736

  14. COCOA: tracking in aerial imagery

    NASA Astrophysics Data System (ADS)

    Ali, Saad; Shah, Mubarak

    2006-05-01

    Unmanned Aerial Vehicles (UAVs) are becoming a core intelligence asset for reconnaissance, surveillance and target tracking in urban and battlefield settings. In order to achieve the goal of automated tracking of objects in UAV videos we have developed a system called COCOA. It processes the video stream through number of stages. At first stage platform motion compensation is performed. Moving object detection is performed to detect the regions of interest from which object contours are extracted by performing a level set based segmentation. Finally blob based tracking is performed for each detected object. Global tracks are generated which are used for higher level processing. COCOA is customizable to different sensor resolutions and is capable of tracking targets as small as 100 pixels. It works seamlessly for both visible and thermal imaging modes. The system is implemented in Matlab and works in a batch mode.

  15. The Role of Anticipatory Postural Adjustments in Compensatory Control of Posture: 2. Biomechanical Analysis

    PubMed Central

    Santos, Marcio J.; Kanekar, Neeta; Aruin, Alexander S.

    2010-01-01

    The central nervous system (CNS) utilizes anticipatory (APAs) and compensatory (CPAs) postural adjustments to maintain equilibrium while standing. It is known that these postural adjustments involve displacements of the center of mass (COM) and center of pressure (COP). The purpose of the study was to investigate the relationship between APAs and CPAs from a kinetic and kinematic perspective. Eight subjects were exposed to external predictable and unpredictable perturbations induced at the shoulder level while standing. Kinematic and kinetic data were recorded and analyzed during the time duration typical for anticipatory and compensatory postural adjustments. When the perturbations were unpredictable, the COM and COP displacements were larger compared to predictable conditions with APAs. Thus, the peak of COM displacement, after the pendulum impact, in the posterior direction reached 28 ± 9.6 mm in the unpredictable conditions with no APAs whereas it was 1.6 times smaller, reaching 17 ± 5.5 mm during predictable perturbations. Similarly, after the impact, the peak of COP displacement in the posterior direction was 60 ± 14 mm for unpredictable conditions and 28 ± 3.6 mm for predictable conditions. Finally, the times of the peak COM and COP displacements were similar in the predictable and unpredictable conditions. This outcome provides additional knowledge about how body balance is controlled in presence and in absence of information about the forthcoming perturbation. Moreover, it suggests that control of posture could be enhanced by better utilization of APAs and such an approach could be considered as a valuable modality in the rehabilitation of individuals with balance impairment. PMID:20156693

  16. Putative spinal interneurons mediating postural limb reflexes provide basis for postural control in different planes

    PubMed Central

    Zelenin, Pavel V.; Hsu, Li-Ju; Lyalka, Vladimir F.; Orlovsky, Grigori N.; Deliagina, Tatiana G.

    2014-01-01

    The dorsal-side-up trunk orientation in standing quadrupeds is maintained by the postural system driven mainly by somatosensory inputs from the limbs. Postural limb reflexes (PLRs) represent a substantial component of this system. Earlier we described spinal neurons presumably contributing to the generation of PLRs. The first aim of the present study was to reveal trends in the distribution of neurons with different parameters of PLR-related activity across the gray matter of the spinal cord. The second aim was to estimate the contribution of PLR-related neurons with different patterns of convergence of sensory inputs from the limbs to stabilization of body orientation in different planes. For this purpose, the head and vertebral column of the decerebrate rabbit were fixed, whereas the hindlimbs were positioned on a platform. Activity of individual neurons from L5–L6 was recorded during PLRs evoked by lateral tilts of the platform. In addition, the neurons were tested by tilts of the platform under only the ipsilateral or only the contralateral limb, as well as during in-phase tilts of the platforms under both limbs. We found that, across the spinal gray matter, strength of PLR-related neuronal activity and sensory input from the ipsi-limb decreased in the dorso-ventral direction, while strength of the input from the contra-limb increased. A near linear summation of tilt-related sensory inputs from different limbs was found. Functional roles were proposed for individual neurons. The obtained data present the first characterization of posture-related spinal neurons, forming a basis for studies of postural networks impaired by injury. PMID:25370349

  17. The DOE ARM Aerial Facility

    SciTech Connect

    Schmid, Beat; Tomlinson, Jason M.; Hubbe, John M.; Comstock, Jennifer M.; Mei, Fan; Chand, Duli; Pekour, Mikhail S.; Kluzek, Celine D.; Andrews, Elisabeth; Biraud, S.; McFarquhar, Greg

    2014-05-01

    The Department of Energy Atmospheric Radiation Measurement (ARM) Program is a climate research user facility operating stationary ground sites that provide long-term measurements of climate relevant properties, mobile ground- and ship-based facilities to conduct shorter field campaigns (6-12 months), and the ARM Aerial Facility (AAF). The airborne observations acquired by the AAF enhance the surface-based ARM measurements by providing high-resolution in-situ measurements for process understanding, retrieval-algorithm development, and model evaluation that are not possible using ground- or satellite-based techniques. Several ARM aerial efforts were consolidated into the AAF in 2006. With the exception of a small aircraft used for routine measurements of aerosols and carbon cycle gases, AAF at the time had no dedicated aircraft and only a small number of instruments at its disposal. In this "virtual hangar" mode, AAF successfully carried out several missions contracting with organizations and investigators who provided their research aircraft and instrumentation. In 2009, AAF started managing operations of the Battelle-owned Gulfstream I (G-1) large twin-turboprop research aircraft. Furthermore, the American Recovery and Reinvestment Act of 2009 provided funding for the procurement of over twenty new instruments to be used aboard the G-1 and other AAF virtual-hangar aircraft. AAF now executes missions in the virtual- and real-hangar mode producing freely available datasets for studying aerosol, cloud, and radiative processes in the atmosphere. AAF is also engaged in the maturation and testing of newly developed airborne sensors to help foster the next generation of airborne instruments.

  18. Unmanned aerial survey of elephants.

    PubMed

    Vermeulen, Cédric; Lejeune, Philippe; Lisein, Jonathan; Sawadogo, Prosper; Bouché, Philippe

    2013-01-01

    The use of a UAS (Unmanned Aircraft System) was tested to survey large mammals in the Nazinga Game Ranch in the south of Burkina Faso. The Gatewing ×100™ equipped with a Ricoh GR III camera was used to test animal reaction as the UAS passed, and visibility on the images. No reaction was recorded as the UAS passed at a height of 100 m. Observations, made on a set of more than 7000 images, revealed that only elephants (Loxodonta africana) were easily visible while medium and small sized mammals were not. The easy observation of elephants allows experts to enumerate them on images acquired at a height of 100 m. We, therefore, implemented an aerial strip sample count along transects used for the annual wildlife foot count. A total of 34 elephants were recorded on 4 transects, each overflown twice. The elephant density was estimated at 2.47 elephants/km(2) with a coefficient of variation (CV%) of 36.10%. The main drawback of our UAS was its low autonomy (45 min). Increased endurance of small UAS is required to replace manned aircraft survey of large areas (about 1000 km of transect per day vs 40 km for our UAS). The monitoring strategy should be adapted according to the sampling plan. Also, the UAS is as expensive as a second-hand light aircraft. However the logistic and flight implementation are easier, the running costs are lower and its use is safer. Technological evolution will make civil UAS more efficient, allowing them to compete with light aircraft for aerial wildlife surveys. PMID:23405088

  19. Unmanned Aerial Survey of Elephants

    PubMed Central

    Vermeulen, Cédric; Lejeune, Philippe; Lisein, Jonathan; Sawadogo, Prosper; Bouché, Philippe

    2013-01-01

    The use of a UAS (Unmanned Aircraft System) was tested to survey large mammals in the Nazinga Game Ranch in the south of Burkina Faso. The Gatewing ×100™ equipped with a Ricoh GR III camera was used to test animal reaction as the UAS passed, and visibility on the images. No reaction was recorded as the UAS passed at a height of 100 m. Observations, made on a set of more than 7000 images, revealed that only elephants (Loxodonta africana) were easily visible while medium and small sized mammals were not. The easy observation of elephants allows experts to enumerate them on images acquired at a height of 100 m. We, therefore, implemented an aerial strip sample count along transects used for the annual wildlife foot count. A total of 34 elephants were recorded on 4 transects, each overflown twice. The elephant density was estimated at 2.47 elephants/km2 with a coefficient of variation (CV%) of 36.10%. The main drawback of our UAS was its low autonomy (45 min). Increased endurance of small UAS is required to replace manned aircraft survey of large areas (about 1000 km of transect per day vs 40 km for our UAS). The monitoring strategy should be adapted according to the sampling plan. Also, the UAS is as expensive as a second-hand light aircraft. However the logistic and flight implementation are easier, the running costs are lower and its use is safer. Technological evolution will make civil UAS more efficient, allowing them to compete with light aircraft for aerial wildlife surveys. PMID:23405088

  20. Emotional and movement-related body postures modulate visual processing.

    PubMed

    Borhani, Khatereh; Làdavas, Elisabetta; Maier, Martin E; Avenanti, Alessio; Bertini, Caterina

    2015-08-01

    Human body postures convey useful information for understanding others' emotions and intentions. To investigate at which stage of visual processing emotional and movement-related information conveyed by bodies is discriminated, we examined event-related potentials elicited by laterally presented images of bodies with static postures and implied-motion body images with neutral, fearful or happy expressions. At the early stage of visual structural encoding (N190), we found a difference in the sensitivity of the two hemispheres to observed body postures. Specifically, the right hemisphere showed a N190 modulation both for the motion content (i.e. all the observed postures implying body movements elicited greater N190 amplitudes compared with static postures) and for the emotional content (i.e. fearful postures elicited the largest N190 amplitude), while the left hemisphere showed a modulation only for the motion content. In contrast, at a later stage of perceptual representation, reflecting selective attention to salient stimuli, an increased early posterior negativity was observed for fearful stimuli in both hemispheres, suggesting an enhanced processing of motivationally relevant stimuli. The observed modulations, both at the early stage of structural encoding and at the later processing stage, suggest the existence of a specialized perceptual mechanism tuned to emotion- and action-related information conveyed by human body postures. PMID:25556213

  1. Postural activity monitoring for increasing safety in bomb disposal missions

    NASA Astrophysics Data System (ADS)

    Brusey, James; Rednic, Ramona; Gaura, Elena I.; Kemp, John; Poole, Nigel

    2009-07-01

    In enclosed suits, such as those worn by explosive ordnance disposal (EOD) experts, evaporative cooling through perspiration is less effective and, particularly in hot environments, uncompensable heat stress (UHS) may occur. Although some suits have cooling systems, their effectiveness during missions is dependent on the operative's posture. In order to properly assess thermal state, temperature-based assessment systems need to take posture into account. This paper builds on previous work for instrumenting EOD suits with regard to temperature monitoring and proposes to also monitor operative posture with MEMS accelerometers. Posture is a key factor in predicting how body temperature will change and is therefore important in providing local or remote warning of the onset of UHS. In this work, the C4.5 decision tree algorithm is used to produce an on-line classifier that can differentiate between nine key postures from current acceleration readings. Additional features that summarize how acceleration is changing over time are used to improve average classification accuracy to around 97.2%. Without such temporal feature extraction, dynamic postures are difficult to classify accurately. Experimental results show that training over a variety of subjects, and in particular, mixing gender, improves results on unseen subjects. The main advantages of the on-line posture classification system described here are that it is accurate, does not require integration of acceleration over time, and is computationally lightweight, allowing it to be easily supported on wearable microprocessors.

  2. Postural perturbations: new insights for treatment of balance disorders

    NASA Technical Reports Server (NTRS)

    Horak, F. B.; Henry, S. M.; Shumway-Cook, A.; Peterson, B. W. (Principal Investigator)

    1997-01-01

    This article reviews the neural control of posture as understood through studies of automatic responses to mechanical perturbations. Recent studies of responses to postural perturbations have provided a new view of how postural stability is controlled, and this view has profound implications for physical therapy practice. We discuss the implications for rehabilitation of balance disorders and demonstrate how an understanding of the specific systems underlying postural control can help to focus and enrich our therapeutic approaches. By understanding the basic systems underlying control of balance, such as strategy selection, rapid latencies, coordinated temporal spatial patterns, force control, and context-specific adaptations, therapists can focus their treatment on each patient's specific impairments. Research on postural responses to surface translations has shown that balance is not based on a fixed set of equilibrium reflexes but on a flexible, functional motor skill that can adapt with training and experience. More research is needed to determine the extent to which quantification of automatic postural responses has practical implications for predicting falls in patients with constraints in their postural control system.

  3. Effects of elastic band exercise on subjects with rounded shoulder posture and forward head posture

    PubMed Central

    Kim, Tae-Woon; An, Da-In; Lee, Hye-Yun; Jeong, Ho-Young; Kim, Dong-Hyun; Sung, Yun-Hee

    2016-01-01

    [Purpose] This study performed to investigate the effect of elastic band exercise program on the posture of subjects with rounded shoulder and forward head posture. [Subjects and Methods] The body length, forward shoulder angle, craniovertebral angle, and cranial rotation angle of participants (n=12) were measured before and after the exercise program. Furthermore, the thicknesses of the pectoralis major, rhomboid major, and upper trapezius were measured using an ultrasonographic imaging device. The exercises program was conducted with elastic bands, with 15 repetitions per set and 3 sets in total. [Results] The length of the pectoralis major, forward shoulder angle, and craniovertebral angle showed significant changes between before and after the exercise program, whereas the changes in the other measurements were not significant. The thickness of the upper trapezius showed a significant increase between before and after the elastic band exercise. [Conclusion] These findings suggest that the elastic band exercise program used in the study is effective for lengthening the pectoralis major and correcting rounded shoulder and forward head posture. PMID:27390405

  4. Aerial videotape mapping of coastal geomorphic changes

    USGS Publications Warehouse

    Debusschere, Karolien; Penland, Shea; Westphal, Karen A.; Reimer, P. Douglas; McBride, Randolph A.

    1991-01-01

    An aerial geomorphic mapping system was developed to examine the spatial and temporal variability in the coastal geomorphology of Louisiana. Between 1984 and 1990 eleven sequential annual and post-hurricane aerial videotape surveys were flown covering periods of prolonged fair weather, hurricane impacts and subsequent post-storm recoveries. A coastal geomorphic classification system was developed to map the spatial and temporal geomorphic changes between these surveys. The classification system is based on 10 years of shoreline monitoring, analysis of aerial photography for 1940-1989, and numerous field surveys. The classification system divides shorelines into two broad classes: natural and altered. Each class consists of several genetically linked categories of shorelines. Each category is further subdivided into morphologic types on the basis of landform relief, elevation, habitat type, vegetation density and type, and sediment characteristics. The classification is used with imagery from the low-altitude, high-resolution aerial videotape surveys to describe and quantify the longshore and cross-shore geomorphic, sedimentologic, and vegetative character of Louisiana's shoreline systems. The mapping system makes it possible to delineate and map detailed geomorphic habitat changes at a resolution higher than that of conventional vertical aerial photography. Morphologic units are mapped parallel to the regional shoreline from the aerial videotape imagery onto the base maps at a scale of 1:24,000. The base maps were constructed from vertical aerial photography concurrent with the data of the video imagery.

  5. A Methodology for Investigating Adaptive Postural Control

    NASA Technical Reports Server (NTRS)

    McDonald, P. V.; Riccio, G. E.

    1999-01-01

    Our research on postural control and human-environment interactions provides an appropriate scientific foundation for understanding the skill of mass handling by astronauts in weightless conditions (e.g., extravehicular activity or EVA). We conducted an investigation of such skills in NASA's principal mass-handling simulator, the Precision Air-Bearing Floor, at the Johnson Space Center. We have studied skilled movement-body within a multidisciplinary context that draws on concepts and methods from biological and behavioral sciences (e.g., psychology, kinesiology and neurophysiology) as well as bioengineering. Our multidisciplinary research has led to the development of measures, for manual interactions between individuals and the substantial environment, that plausibly are observable by human sensory systems. We consider these methods to be the most important general contribution of our EVA investigation. We describe our perspective as control theoretic because it draws more on fundamental concepts about control systems in engineering than it does on working constructs from the subdisciplines of biomechanics and motor control in the bio-behavioral sciences. At the same time, we have attempted to identify the theoretical underpinnings of control-systems engineering that are most relevant to control by human beings. We believe that these underpinnings are implicit in the assumptions that cut across diverse methods in control-systems engineering, especially the various methods associated with "nonlinear control", "fuzzy control," and "adaptive control" in engineering. Our methods are based on these theoretical foundations rather than on the mathematical formalisms that are associated with particular methods in control-systems engineering. The most important aspects of the human-environment interaction in our investigation of mass handling are the functional consequences that body configuration and stability have for the pick up of information or the achievement of

  6. Myopia, posture and the visual environment.

    PubMed

    Charman, W Neil

    2011-09-01

    Evidence for a possible role for the peripheral retina in the control of refractive development is discussed, together with Howland's suggestion (Paper presented at the 13th International Myopia Conference, Tubingen, Germany, July 26-29, 2010) that signals to generate appropriate growth might be derived from ocular oblique astigmatism. The dependence of this, or similar peripheral mechanisms, on exposure to a uniform field of near-zero dioptric vergence is emphasized: this is required to ensure a consistent relationship between the astigmatic image fields and the retina. This condition is satisfied by typical outdoor environments. In contrast, indoor environments are likely to be unfavourable to peripherally-based emmetropization, since dioptric stimuli may vary widely across the visual field. This is particularly the case when short working distances or markedly asymmetric head postures with respect to the visual task are adopted. PMID:21410496

  7. Postural dependence of human locomotion during gait initiation.

    PubMed

    Mille, Marie-Laure; Simoneau, Martin; Rogers, Mark W

    2014-12-15

    The initiation of human walking involves postural motor actions for body orientation and balance stabilization that must be effectively integrated with locomotion to allow safe and efficient transport. Our ability to coordinately adapt these functions to environmental or bodily changes through error-based motor learning is essential to effective performance. Predictive compensations for postural perturbations through anticipatory postural adjustments (APAs) that stabilize mediolateral (ML) standing balance normally precede and accompany stepping. The temporal sequencing between these events may involve neural processes that suppress stepping until the expected stability conditions are achieved. If so, then an unexpected perturbation that disrupts the ML APAs should delay locomotion. This study investigated how the central nervous system (CNS) adapts posture and locomotion to perturbations of ML standing balance. Healthy human adults initiated locomotion while a resistance force was applied at the pelvis to perturb posture. In experiment 1, using random perturbations, step onset timing was delayed relative to the APA onset indicating that locomotion was withheld until expected stability conditions occurred. Furthermore, stepping parameters were adapted with the APAs indicating that motor prediction of the consequences of the postural changes likely modified the step motor command. In experiment 2, repetitive postural perturbations induced sustained locomotor aftereffects in some parameters (i.e., step height), immediate but rapidly readapted aftereffects in others, or had no aftereffects. These results indicated both rapid but transient reactive adaptations in the posture and gait assembly and more durable practice-dependent changes suggesting feedforward adaptation of locomotion in response to the prevailing postural conditions. PMID:25231611

  8. Contribution of supraspinal systems to generation of automatic postural responses.

    PubMed

    Deliagina, Tatiana G; Beloozerova, Irina N; Orlovsky, Grigori N; Zelenin, Pavel V

    2014-01-01

    Different species maintain a particular body orientation in space due to activity of the closed-loop postural control system. In this review we discuss the role of neurons of descending pathways in operation of this system as revealed in animal models of differing complexity: lower vertebrate (lamprey) and higher vertebrates (rabbit and cat). In the lamprey and quadruped mammals, the role of spinal and supraspinal mechanisms in the control of posture is different. In the lamprey, the system contains one closed-loop mechanism consisting of supraspino-spinal networks. Reticulospinal (RS) neurons play a key role in generation of postural corrections. Due to vestibular input, any deviation from the stabilized body orientation leads to activation of a specific population of RS neurons. Each of the neurons activates a specific motor synergy. Collectively, these neurons evoke the motor output necessary for the postural correction. In contrast to lampreys, postural corrections in quadrupeds are primarily based not on the vestibular input but on the somatosensory input from limb mechanoreceptors. The system contains two closed-loop mechanisms - spinal and spino-supraspinal networks, which supplement each other. Spinal networks receive somatosensory input from the limb signaling postural perturbations, and generate spinal postural limb reflexes. These reflexes are relatively weak, but in intact animals they are enhanced due to both tonic supraspinal drive and phasic supraspinal commands. Recent studies of these supraspinal influences are considered in this review. A hypothesis suggesting common principles of operation of the postural systems stabilizing body orientation in a particular plane in the lamprey and quadrupeds, that is interaction of antagonistic postural reflexes, is discussed. PMID:25324741

  9. Contribution of supraspinal systems to generation of automatic postural responses

    PubMed Central

    Deliagina, Tatiana G.; Beloozerova, Irina N.; Orlovsky, Grigori N.; Zelenin, Pavel V.

    2014-01-01

    Different species maintain a particular body orientation in space due to activity of the closed-loop postural control system. In this review we discuss the role of neurons of descending pathways in operation of this system as revealed in animal models of differing complexity: lower vertebrate (lamprey) and higher vertebrates (rabbit and cat). In the lamprey and quadruped mammals, the role of spinal and supraspinal mechanisms in the control of posture is different. In the lamprey, the system contains one closed-loop mechanism consisting of supraspino-spinal networks. Reticulospinal (RS) neurons play a key role in generation of postural corrections. Due to vestibular input, any deviation from the stabilized body orientation leads to activation of a specific population of RS neurons. Each of the neurons activates a specific motor synergy. Collectively, these neurons evoke the motor output necessary for the postural correction. In contrast to lampreys, postural corrections in quadrupeds are primarily based not on the vestibular input but on the somatosensory input from limb mechanoreceptors. The system contains two closed-loop mechanisms – spinal and spino-supraspinal networks, which supplement each other. Spinal networks receive somatosensory input from the limb signaling postural perturbations, and generate spinal postural limb reflexes. These reflexes are relatively weak, but in intact animals they are enhanced due to both tonic supraspinal drive and phasic supraspinal commands. Recent studies of these supraspinal influences are considered in this review. A hypothesis suggesting common principles of operation of the postural systems stabilizing body orientation in a particular plane in the lamprey and quadrupeds, that is interaction of antagonistic postural reflexes, is discussed. PMID:25324741

  10. Postural responses to changing task conditions.

    PubMed

    Hansen, P D; Woollacott, M H; Debu, B

    1988-01-01

    The experimental goal was to investigate discrepancies in the literature concerning postural adaptation and to determine if the prior presentation of horizontal perturbations affected the amplitude of responses to rotational perturbations. Surface EMG recordings from lower leg muscles (gastrocnemius (GAS) and tibialis anterior (TA)) were recorded in twelve subjects, and the amplitudes of the responses were statistically analyzed. We did not find differences between the responses to rotational perturbations which preceded or followed horizontal perturbations. This finding did not support the hypothesis that differences in the order of presentation of the different types of perturbations accounted for the discrepancies in the literature. Furthermore, our design did not show the progressive elimination of the GAS response within three to five sequential trials. Instead, we found a slow but significant response amplitude reduction over ten trials without yielding a permanent disappearance of the response. When analyzing the GAS responses to the rotational perturbations only, we found two components that contributed to the response reduction: 1) an initial reduction between trials one and subsequent trials, which could be due to habituation of a startle-like response; and 2) a second reduction which was more gradual. Our results also showed an immediate change in the response amplitude on the first trial, when the type of perturbation was changed. This is inconsistent with the view that ankle musculature stretch and joint movement are the primary inputs driving the postural responses. Since small ankle dorsiflexing rotations produced by the platform translations caused large GAS responses while large ankle dorsiflexing rotations produced by direct platform rotations caused small GAS responses, this suggests that multiple sensory inputs contribute to the responses. We propose that an initial compensation to a new perturbation type occurs within the first trial by the

  11. Postural Instability in Children with ADHD Is Improved by Methylphenidate

    PubMed Central

    Bucci, Maria P.; Stordeur, Coline; Acquaviva, Eric; Peyre, Hugo; Delorme, Richard

    2016-01-01

    HIGHLIGHTS Both spatial and temporal analyses of the Center of Pressure demonstrate that children with ADHD have poorer postural control than typically developing sex-, age-, and IQ-matched children.Poor sensory integration in postural control could partially explained the deficits in postural stability in children with ADHD.MPH treatment improves postural performance in both spatial and temporal domains in children with ADHD.MPH improves postural control specifically when visual and proprioceptive inputs are misleading.Such improvement could be due to MPH effects on neurons, facilitating cerebellar processing of postural control. The aim of this study was to examine postural control in children with ADHD and explore the effect of methylphenidate (MPH), using spatial and temporal analyses of the center of pressure (CoP). Thirty-eight children with ADHD (mean age 9.82 ± 0.37 years) and 38 sex- age- and IQ-matched children with typically development were examined. Postural stability was evaluated using the Multitest Equilibre machine (Framiral®) at inclusion and after 1 month of MPH in children with ADHD. Postural stability was assessed by recording under several conditions: with eyes open and fixed on a target, with eyes closed and with vision perturbed by optokinetic stimulation, on stable and unstable platforms. At inclusion, we observed poor spatial and temporal postural stability in children with ADHD. The spectral power index was higher in children with ADHD than in controls. Canceling time was shorter at low and medium frequencies of oscillation and longer at higher frequencies in children with ADHD. After 1 month of MPH, the surface area and mean velocity of the CoP decreased significantly under the most complex conditions (unstable platform in the absence of proprioceptive and visual inputs). The spectral power index decreased significantly after MPH while the canceling time did not change. Poor postural control in children with ADHD supports the

  12. Ankle sprain and postural sway in basketball players.

    PubMed

    Leanderson, J; Wykman, A; Eriksson, E

    1993-01-01

    The present study compares postural ankle stability between previously injured basketball players, uninjured players and a control/group. Postural sway was recorded and analysed by stabilometry using a specially designed computer-assisted forceplate. Recordings were obtained for 60 s on each foot. The stabilometric results in the players with no previous injuries did not differ from those in the controls. Players with a previously injured ankle differed significantly from the control group. These players had a larger mean postural sway and used a larger sway area. PMID:8536030

  13. Functional asymmetry of posture and body system regulation

    NASA Technical Reports Server (NTRS)

    Boloban, V. N.; Otsupok, A. P.

    1980-01-01

    The manifestation of functional asymmetry during the regulation of an athlete's posture and a system of bodies and its effect on the execution of individual and group acrobatic exercises were studied. Functional asymmetry of posture regulation was recorded in acrobats during the execution of individual and group exercises. It was shown that stability is maintained at the expense of bending and twisting motions. It is important to consider whether the functional asymmetry of posture regulation is left or right sided in making up pairs and groups of acrobats.

  14. Postural Instability in Children with ADHD Is Improved by Methylphenidate.

    PubMed

    Bucci, Maria P; Stordeur, Coline; Acquaviva, Eric; Peyre, Hugo; Delorme, Richard

    2016-01-01

    HIGHLIGHTS Both spatial and temporal analyses of the Center of Pressure demonstrate that children with ADHD have poorer postural control than typically developing sex-, age-, and IQ-matched children.Poor sensory integration in postural control could partially explained the deficits in postural stability in children with ADHD.MPH treatment improves postural performance in both spatial and temporal domains in children with ADHD.MPH improves postural control specifically when visual and proprioceptive inputs are misleading.Such improvement could be due to MPH effects on neurons, facilitating cerebellar processing of postural control. The aim of this study was to examine postural control in children with ADHD and explore the effect of methylphenidate (MPH), using spatial and temporal analyses of the center of pressure (CoP). Thirty-eight children with ADHD (mean age 9.82 ± 0.37 years) and 38 sex- age- and IQ-matched children with typically development were examined. Postural stability was evaluated using the Multitest Equilibre machine (Framiral®) at inclusion and after 1 month of MPH in children with ADHD. Postural stability was assessed by recording under several conditions: with eyes open and fixed on a target, with eyes closed and with vision perturbed by optokinetic stimulation, on stable and unstable platforms. At inclusion, we observed poor spatial and temporal postural stability in children with ADHD. The spectral power index was higher in children with ADHD than in controls. Canceling time was shorter at low and medium frequencies of oscillation and longer at higher frequencies in children with ADHD. After 1 month of MPH, the surface area and mean velocity of the CoP decreased significantly under the most complex conditions (unstable platform in the absence of proprioceptive and visual inputs). The spectral power index decreased significantly after MPH while the canceling time did not change. Poor postural control in children with ADHD supports the

  15. Aerial Terrain Mapping Using Unmanned Aerial Vehicle Approach

    NASA Astrophysics Data System (ADS)

    Tahar, K. N.

    2012-08-01

    This paper looks into the latest achievement in the low-cost Unmanned Aerial Vehicle (UAV) technology in their capacity to map the semi-development areas. The objectives of this study are to establish a new methodology or a new algorithm in image registration during interior orientation process and to determine the accuracy of the photogrammetric products by using UAV images. Recently, UAV technology has been used in several applications such as mapping, agriculture and surveillance. The aim of this study is to scrutinize the usage of UAV to map the semi-development areas. The performance of the low cost UAV mapping study was established on a study area with two image processing methods so that the results could be comparable. A non-metric camera was attached at the bottom of UAV and it was used to capture images at both sites after it went through several calibration steps. Calibration processes were carried out to determine focal length, principal distance, radial lens distortion, tangential lens distortion and affinity. A new method in image registration for a non-metric camera is discussed in this paper as a part of new methodology of this study. This method used the UAV Global Positioning System (GPS) onboard to register the UAV image for interior orientation process. Check points were established randomly at both sites using rapid static Global Positioning System. Ground control points are used for exterior orientation process, and check point is used for accuracy assessment of photogrammetric product. All acquired images were processed in a photogrammetric software. Two methods of image registration were applied in this study, namely, GPS onboard registration and ground control point registration. Both registrations were processed by using photogrammetric software and the result is discussed. Two results were produced in this study, which are the digital orthophoto and the digital terrain model. These results were analyzed by using the root mean square

  16. Postural Stability of Patients with Schizophrenia during Challenging Sensory Conditions: Implication of Sensory Integration for Postural Control

    PubMed Central

    Chen, Chiung-Ling; Lou, Shu-Zon; Wang, Wei-Tsan; Wu, Jui-Yen

    2016-01-01

    Postural dysfunctions are prevalent in patients with schizophrenia and affect their daily life and ability to work. In addition, sensory functions and sensory integration that are crucial for postural control are also compromised. This study intended to examine how patients with schizophrenia coordinate multiple sensory systems to maintain postural stability in dynamic sensory conditions. Twenty-nine patients with schizophrenia and 32 control subjects were recruited. Postural stability of the participants was examined in six sensory conditions of different level of congruency of multiple sensory information, which was based on combinations of correct, removed, or conflicting sensory inputs from visual, somatosensory, and vestibular systems. The excursion of the center of pressure was measured by posturography. Equilibrium scores were derived to indicate the range of anterior-posterior (AP) postural sway, and sensory ratios were calculated to explore ability to use sensory information to maintain balance. The overall AP postural sway was significantly larger for patients with schizophrenia compared to the controls [patients (69.62±8.99); controls (76.53±7.47); t1,59 = -3.28, p<0.001]. The results of mixed-model ANOVAs showed a significant interaction between the group and sensory conditions [F5,295 = 5.55, p<0.001]. Further analysis indicated that AP postural sway was significantly larger for patients compared to the controls in conditions containing unreliable somatosensory information either with visual deprivation or with conflicting visual information. Sensory ratios were not significantly different between groups, although small and non-significant difference in inefficiency to utilize vestibular information was also noted. No significant correlations were found between postural stability and clinical characteristics. To sum up, patients with schizophrenia showed increased postural sway and a higher rate of falls during challenging sensory conditions, which

  17. Verification of Potency of Aerial Digital Oblique Cameras for Aerial Photogrammetry in Japan

    NASA Astrophysics Data System (ADS)

    Nakada, Ryuji; Takigawa, Masanori; Ohga, Tomowo; Fujii, Noritsuna

    2016-06-01

    Digital oblique aerial camera (hereinafter called "oblique cameras") is an assembly of medium format digital cameras capable of shooting digital aerial photographs in five directions i.e. nadir view and oblique views (forward and backward, left and right views) simultaneously and it is used for shooting digital aerial photographs efficiently for generating 3D models in a wide area. For aerial photogrammetry of public survey in Japan, it is required to use large format cameras, like DMC and UltraCam series, to ensure aerial photogrammetric accuracy. Although oblique cameras are intended to generate 3D models, digital aerial photographs in 5 directions taken with them should not be limited to 3D model production but they may also be allowed for digital mapping and photomaps of required public survey accuracy in Japan. In order to verify the potency of using oblique cameras for aerial photogrammetry (simultaneous adjustment, digital mapping and photomaps), (1) a viewer was developed to interpret digital aerial photographs taken with oblique cameras, (2) digital aerial photographs were shot with an oblique camera owned by us, a Penta DigiCAM of IGI mbH, and (3) accuracy of 3D measurements was verified.

  18. Draper Laboratory small autonomous aerial vehicle

    NASA Astrophysics Data System (ADS)

    DeBitetto, Paul A.; Johnson, Eric N.; Bosse, Michael C.; Trott, Christian A.

    1997-06-01

    The Charles Stark Draper Laboratory, Inc. and students from Massachusetts Institute of Technology and Boston University have cooperated to develop an autonomous aerial vehicle that won the 1996 International Aerial Robotics Competition. This paper describes the approach, system architecture and subsystem designs for the entry. This entry represents a combination of many technology areas: navigation, guidance, control, vision processing, human factors, packaging, power, real-time software, and others. The aerial vehicle, an autonomous helicopter, performs navigation and control functions using multiple sensors: differential GPS, inertial measurement unit, sonar altimeter, and a flux compass. The aerial transmits video imagery to the ground. A ground based vision processor converts the image data into target position and classification estimates. The system was designed, built, and flown in less than one year and has provided many lessons about autonomous vehicle systems, several of which are discussed. In an appendix, our current research in augmenting the navigation system with vision- based estimates is presented.

  19. Officials: Aerial Spraying Working Against Miami Mosquitoes

    MedlinePlus

    ... Officials: Aerial Spraying Working Against Miami Mosquitoes The insects are to blame for first cases of Zika ... mosquitoes in a part of Miami where the insects have been linked to 16 cases of Zika ...

  20. Rangeland monitoring with unmanned aerial vehicles (UAVs)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unmanned aerial vehicles (UAVs) have great potential for rangeland management applications, such as monitoring vegetation change, developing grazing strategies, determining rangeland health, and assessing remediation treatment effectiveness. UAVs have several advantages: they can be deployed quickly...

  1. Locating buildings in aerial photos

    NASA Technical Reports Server (NTRS)

    Green, James S.

    1994-01-01

    Algorithms and techniques for use in the identification and location of large buildings in digitized copies of aerial photographs are developed and tested. The building data would be used in the simulation of objects located in the vicinity of an airport that may be detected by aircraft radar. Two distinct approaches are considered. Most building footprints are rectangular in form. The first approach studied is to search for right-angled corners that characterize rectangular objects and then to connect these corners to complete the building. This problem is difficult because many nonbuilding objects, such as street corners, parking lots, and ballparks often have well defined corners which are often difficult to distinguish from rooftops. Furthermore, rooftops come in a number of shapes, sizes, shadings, and textures which also limit the discrimination task. The strategy used linear sequences of different samples to detect straight edge segments at multiple angles and to determine when these segments meet at approximately right-angles with respect to each other. This technique is effective in locating corners. The test image used has a fairly rectangular block pattern oriented about thirty degrees clockwise from a vertical alignment, and the overall measurement data reflect this. However, this technique does not discriminate between buildings and other objects at an operationally suitable rate. In addition, since multiple paths are tested for each image pixel, this is a time consuming task. The process can be speeded up by preprocessing the image to locate the more optimal sampling paths. The second approach is to rely on a human operator to identify and select the building objects and then to have the computer determine the outline and location of the selected structures. When presented with a copy of a digitized aerial photograph, the operator uses a mouse and cursor to select a target building. After a button on the mouse is pressed, with the cursor fully within

  2. Advancing Leadership in Sport: Time to Take Off the Blinkers?

    PubMed

    Cruickshank, Andrew; Collins, Dave

    2016-09-01

    While leadership is one of the most significant factors in sport, most research has focused on who effective leaders are and what they overtly do rather than why and how they lead in a certain way at a certain time. Presumably shaped by social norms, the bulk of this work has also overstated the role of bright (or socially desirable) leadership intentions and behaviours; or at least overlooked how this style fits with the 'darker' (or socially undesirable) intentions and behaviours that are prevalent and effective in applied practice. Contextualising this situation against the origins and dominant paradigms of sport-specific study, we therefore highlight the need for greater emphasis on both the cognitive and dark sides of leadership. Regarding the former, we argue that expert leadership requires cognitive excellence given that optimal and consistent impact requires the conscious selection, combination and deployment of leadership behaviours. Regarding the latter, we also argue that bright intentions and behaviours can often only be a part of an effective leadership repertoire and can beneficially operate in tandem with inherently dark alternatives. To advance knowledge and practice, we therefore call for a more pragmatic approach to research that considers both the cognitive mechanisms-namely professional judgement and decision making-and the full spectrum of intentions and behaviours that underpin real world leadership. PMID:26914268

  3. CFC alternatives fail to take off in Europe

    SciTech Connect

    Chynoweth, E.

    1993-02-17

    Huge differences are emerging in U.S. and European demand for chlorofluorocarbon (CFC) alternatives. European refrigeration system makers have made virtually no progress in replacing ozone-depleting CFCs with alternatives, according to ICI Klea (Runcorn, U.K.) - the newly named CFC-alternatives business of ICI (London). Meanwhile, U.S. tax incentives are spurring demand for CFC alternatives. Under European Community regulation, production and consumption of CFCs should be 50% lower as of Jan. 1, 1993, compared with the base year of 1986, and 85% lower by Jan. 1, 1994. CFC producers say the first target has been reached, but virtually all the reduction has been achieved through cuts in aerosol use.

  4. Pathfinder-Plus takes off on flight in Hawaii

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Pathfinder-Plus on a flight over Hawaii in 1998. Pathfinder was a remotely controlled, solar-powered flying wing, designed and built as a proof-of-concept vehicle for a much larger aircraft capable of flying at extremely high altitudes for weeks at a time. It was built by AeroVironment, Inc., a California company that developed the human-powered Gossamer Condor and Gossamer Albatross lightweight aircraft during the 1970s, and later made the solar-electric powered Gossamer Penguin and Solar Challenger. The basic configuration and concepts for Pathfinder were first realized with the HALSOL (High Altitude Solar) aircraft, built in 1983 by AeroVironment and the Lawrence Livermore Laboratory. Pathfinder was constructed of advanced composites, plastics, and foam, and despite a wingspan of nearly 100 feet, it weighed only about 600 pounds. Pathfinder was one of several unpiloted prototypes under study by NASA's ERAST (Environmental Research Aircraft and Sensor Technology) program, a NASA-industry alliance which is helping develop advanced technologies that will enable aircraft to study the earth's environment during extremely long flights at altitudes in excess of 100,000 feet. (See project description below for Pathfinder's conversion to Pathfinder Plus.) In 1998, the Pathfinder solar-powered flying wing (see its photographs and project description) was modified into the longer-winged Pathfinder Plus configuration and on Aug. 6, 1998, Pathfinder Plus set an altitude record (for propeller-driven aircraft) of approximately 80,285 feet at the Pacific Missile Range Facility. The goal of the Pathfinder Plus flights was to validate new solar, aerodynamic, propulsion, and systems technology developed for its successor, the Centurion, which was designed to reach and sustain altitudes in the 100,000-foot range. The Centurion was succeeded by the Helios Prototype with a goal of reaching and sustaining flight at an altitude of 100,000 feet and flying non-stop for at least 4 days above 50,000 feet. Major activities of Pathfinder Plus' Hawaiian flights included detection of forest nutrient status, forest regrowth after damage caused by Hurricane Iniki in 1992, sediment/algal concentrations in coastal waters, and assessment of coral reef health. Pathfinder science activities were coordinated by NASA's Ames Research Center, Mountain View, California, and included researchers from the University of Hawaii and the University of California. Pathfinder is part of NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program managed by NASA's Dryden Flight Research Center, Edwards, California. Pathfinder and Pathfinder Plus were designed, built, and operated by AeroVironment, Inc., Monrovia, California. Pathfinder had a 98.4-foot wing span and weighed 560 pounds. Pathfinder Plus has a 121-foot wing span and weighs about 700 pounds. Pathfinder was powered by six electric motors while Pathfinder Plus has eight. Pathfinder's solar arrays produced approximately 8,000 watts of power while Pathfinder Plus' solar arrays produce about 12,500 watts of power. Both Pathfinder aircraft were built primarily of composites, plastic, and foam.

  5. India's pharmaceutical industry: hype or high tech take-off?

    PubMed

    Malhotra, Prabodh; Lofgren, Hans

    2004-11-01

    India has built a large pharmaceutical industry through an array of measures in support of domestic firms. The absence of product patents enabled Indian companies to become world leading producers of generic versions of patented drugs. Low costs and a strong engineering tradition continue to sustain competitive strength. The implementation of the World Trade Organization patent regime in 2005 is driving a transformation of the industry. Key elements of the present shake-up include the return of 'big pharma' companies on a large scale and the emergence of several Indian firms that aim to become fully-fledged research-based multinationals. This article provides a description of the development and structure of the Indian pharmaceutical industry and explores questions and challenges arising from its integration into global markets. PMID:15527398

  6. Aeronautics Study Takes Off! Glider Design for Beginners

    ERIC Educational Resources Information Center

    Lazaros, Edward J.; Carlson, Katie

    2008-01-01

    Study of aeronautics is an interesting and motivating subject for students and educators alike. The activity described in this article--appropriate for upper elementary or middle school students--provides an excellent introduction to airplane design and the science of aerodynamics. It also gives students good experience applying knowledge from a…

  7. Aviation Centers Take Off as Airlines Face Pilot Shortfall.

    ERIC Educational Resources Information Center

    Mangan, Katherine S.

    2000-01-01

    Addresses aviation training requirements for pilots planning to fly for commercial airlines within or outside the United States. Describes two aviation training programs at Western Michigan University, a fast-track 13-month program and the traditional four-year program required for U.S. pilots. Notes that decreasing numbers of pilots trained in…

  8. Taking Off the Cape: The Stories of Novice Urban Leadership

    ERIC Educational Resources Information Center

    Tredway, Lynda; Brill, Fred; Hernandez, Janette

    2007-01-01

    New administrators in urban schools face enormous challenges. The novice leaders in this study are graduates of a preparation program at UC Berkeley, and are participants in a leadership induction program. This research examines one aspect of their new position--disciplinarian--through the lens of leadership stories. Although the middle manager…

  9. Federal program for regulating highly hazardous materials finally takes off

    SciTech Connect

    Lessard, P.C.

    1996-11-01

    The Risk Management Program (RMP) rule, Section 112(r) of the Clean Air Act (CAA), was signed on May 24 and finalized on June 20. RMP is one of the most comprehensive, technically based regulatory programs for preventing, detecting and responding to accidental hazardous materials releases to have been issued in recent times. Although facilities have three years to comply, EPA estimates that the rule will affect an estimated 66,000 facilities that store highly hazardous or acutely toxic materials. The 1990 CAA Amendments are designed to prevent accidental releases of highly hazardous chemicals from stationary sources. Two significant regulatory programs that have emerged from the revised CAA are the Process Safety Management (PSM) standard and RMP. PSM is designed to protect employees and regulated by the Occupational Safety and Health Administration. RMP`s purpose is to protect the public and the environment from highly hazardous chemicals. It authorizes EPA to create a list of substances (distinct from the list generated under PSM) known to cause serious adverse effects and to implement a program for accidental chemical release prevention.

  10. A Soft Take-Off in the Direction of "Bologna"

    ERIC Educational Resources Information Center

    Casaravilla Gil, Ana; Cava, Maria Victoria Cuevas; del Rio Merino, Mercedes; Arrebola, Carmen Vinas

    2011-01-01

    In the 2009-2010 academic year, ten new degrees have begun to be taught at the UPM (Universidad Politecnica Madrid), which is the first group of degrees that this university will offer within the framework of the EHEA (European Higher Education Area). One of these new degrees is the Building Engineering Degree, which was implemented in September…

  11. How to Properly Put On, Take Off a Disposable Respirator

    MedlinePlus

    ... the nose piece at your fingertips. Checking Your Seal 2 Cup the respirator in your hand allowing ... quick breath in to check whether the respirator seals tightly to the face. Place both hands completely ...

  12. "EC to go" takes off at Maryland sites.

    PubMed

    2000-03-01

    Baltimore-based Planned Parenthood of Maryland and the Baltimore City Health Department have joined forces in "EC to Go," which distributes free emergency contraceptive pills (ECPs) through the seven affiliate sites of Planned Parenthood and the three family planning centers of the city. The distribution program was started in October 1999 and funds were provided by an undisclosed area foundation. Although the program is still in its infancy, it has recorded some 800 prescriptions of ECPs in the last fiscal year, and 600 prescriptions have been logged in just the first 6 months of the current fiscal year. To inform the public about the program, Planned Parenthood developed newspaper advertisements, a 60-second radio spot, and coupon distributions, all of which emphasize the fact that emergency contraception is a higher dose of birth control, which can prevent pregnancy if taken within 72 hours of unprotected sex. PMID:12349550

  13. Galvanic vestibular stimulation for analysis of postural adaptation and stability.

    PubMed

    Johansson, R; Magnusson, M; Fransson, P A

    1995-03-01

    Human postural dynamics was investigated in 12 normal subjects by means of a force platform recording body sway, induced by bipolar transmastoid galvanic stimulation of the vestibular nerve and labyrinth. The model adopted was that of an inverted segmented pendulum, the dynamics of postural control being assumed to be reflected in the stabilizing forces actuated by the feet as a result of complex muscular activity subject to state feedback of body sway and position. Time-series analysis demonstrates that a transfer function from stimulus to sway-force response with specific parameters can be identified. In addition, adaptation to the vestibular stimulus is demonstrated to exist, and we describe this phenomenon using quantification in terms of a postural adaptation time constant in the range of 40-50 s. The results suggest means to evaluate adaptive behavior and postural control in the erect human being which may be useful in the rehabilitation of individuals striving to regain upright stance. PMID:7698784

  14. Postural changes following sensory reinterpretation as an analog to spaceflight

    NASA Technical Reports Server (NTRS)

    Paloski, William H.; Harm, D. L.; Reschke, M. F.; Doxey, D. D.; Skinner, N. C.; Michaud, L. J.; Parker, D. E.

    1990-01-01

    Postural control changes noted in astronauts immediately following spaceflight are thought to be caused by inflight adaptative changes in Central Nervous System (CNS) processing of sensory information from the visual, vestibular, and proprioceptive systems. In order to elicit these adaptative changes in ground based studies, a Tilt Translation Device (TTD) which causes the CNS of exposed subjects to reinterpret tilt generated sensory inputs from the otolith organs as linear translation of the subject was developed. This device was designed to simulate partially the stimulus rearrangement experienced by astronauts during microgravity. Postural stability is assessed in ten subjects before and after 30 minutes of exposure to TTD. The resulting data suggests that exposure to TTD causes decreases in postural stability and shifts in postflight studies of astronauts. It is concluded that the TTD may be an effective weightlessness simulator, and that the postural changes following TTD exposure may provide a useful dependent measure for evaluation of this apparatus.

  15. Dental occlusion modifies gaze and posture stabilization in human subjects.

    PubMed

    Gangloff, P; Louis, J P; Perrin, P P

    2000-11-01

    Repercussion of dental occlusion was tested upon postural and gaze stabilization, the latter with a visuo-motor task evaluated by shooting performances. Eighteen permit holders shooters and 18 controls were enrolled in this study. Postural control was evaluated in both groups according to four mandibular positions imposed by interocclusal splints: (i) intercuspal occlusion (IO), (ii) centric relation (CR), (iii) physiological side lateral occlusion and (iv) controlateral occlusion, in order to appreciate the impact of the splints upon orthostatism. Postural control and gaze stabilization quality decreased, from the best to the worst, with splints in CR, IO and lateral occlusion. In shooters, the improvement in postural control was parallel to superior shooting performance. A repercussion of dental occlusion upon proprioception and visual stabilization is suggested by these data. PMID:11036196

  16. Transition from Rocking to Crawling: Postural Constraints on Infant Movement.

    ERIC Educational Resources Information Center

    Goldfield, Eugene C.

    1989-01-01

    Investigated postural constraints on movement of 15 6-month-old infants. Results suggested that each of the developing capabilities of orienting, reaching, and kicking assumed a specific function for locomotion at the stage of crawling. (RJC)

  17. Postural sway and the frequency of horizontal eye movements.

    PubMed

    Stoffregen, Thomas A; Bardy, Benoît G; Bonnet, Céderick T; Hove, Philip; Oullier, Olivier

    2007-01-01

    In two experiments, participants were asked to shift gaze to follow horizontal target oscillation to allow us to investigate relations between eye movements and postural dynamics. Postural sway variability was reduced during target oscillation when compared to sway while viewing a stationary target. The influence of target oscillation on sway was independent of target oscillation frequency. Similar results were obtained with measurements of the center of pressure (Experiment 1) and the displacement of body segments (Experiment 2). The overall results are not consistent with the view that eye movements and postural control compete for limited central processing resources. The results are consistent with the thesis of a functional integration of postural control with visual performance. PMID:17392569

  18. A quantitative measurement method for comparison of seated postures.

    PubMed

    Hillman, Susan J; Hollington, James

    2016-05-01

    This technical note proposes a method to measure and compare seated postures. The three-dimensional locations of palpable anatomical landmarks corresponding to the anterior superior iliac spines, clavicular notch, head, shoulders and knees are measured in terms of x, y and z co-ordinates in the reference system of the measuring apparatus. These co-ordinates are then transformed onto a body-based axis system which allows comparison within-subject. The method was tested on eleven unimpaired adult participants and the resulting data used to calculate a Least Significant Difference (LSD) for the measure, which is used to determine whether two postures are significantly different from one another. The method was found to be sensitive to the four following standardised static postural perturbations: posterior pelvic tilt, pelvic obliquity, pelvic rotation, and abduction of the thighs. The resulting data could be used as an outcome measure for the postural alignment aspect of seating interventions in wheelchairs. PMID:26920073

  19. Hand posture recognizer based on separator wavelet networks

    NASA Astrophysics Data System (ADS)

    Bouchrika, Tahani; Jemai, Olfa; Zaied, Mourad; Ben Amar, Chokri

    2015-12-01

    This paper presents a novel hand posture recognizer based on separator wavelet networks (SWNs). Aiming at creating a robust and rapid hand posture recognizer, we have contributed by proposing a new training algorithm for the wavelet network classifier based on fast wavelet transform (FWN). So, the contribution resides in reducing the number of WNs modeling training data. To make that, inspiring from the adaboost feature selection method, we thought to create SWNs (n-1 WNs for n classes) instead of modeling each training sample by its wavelet network (WN). By proposing the new training algorithm, the recognition phase will be positively influenced. It will be more rapid thanks to the reduction of the number of comparisons between test images WNs and training WNs. Comparisons with other works, employing universal hand posture datasets are presented and discussed. Obtained results have shown that the new hand posture recognizer is comparable to previously established ones.

  20. Movement plans for posture selection do not transfer across hands

    PubMed Central

    Schütz, Christoph; Schack, Thomas

    2015-01-01

    In a sequential task, the grasp postures people select depend on their movement history. This motor hysteresis effect results from the reuse of former movement plans and reduces the cognitive cost of movement planning. Movement plans for hand trajectories not only transfer across successive trials, but also across hands. We therefore asked whether such a transfer would also be found in movement plans for hand postures. To this end, we designed a sequential, continuous posture selection task. Participants had to open a column of drawers with cylindrical knobs in ascending and descending sequences. A hand switch was required in each sequence. Hand pro/supination was analyzed directly before and after the hand switch. Results showed that hysteresis effects were present directly before, but absent directly after the hand switch. This indicates that, in the current study, movement plans for hand postures only transfer across trials, but not across hands. PMID:26441734

  1. Observing working postures in industry: Examples of OWAS application.

    PubMed

    Karhu, O; Härkönen, R; Sorvali, P; Vepsäläinen, P

    1981-03-01

    A practical method for identifying and evaluating poor working postures, ie the Ovako Working Posture Analysing System (OWAS), was presented in an earlier paper (Karhu et al, 1977). The application of the method is here described by means of two examples. One is a case study undertaken by members of an ergonomics training course, in which a marked improvement in working posture was achieved by OWAS analysis of critical activities. The second illustrates the effect of setting up a multidisciplinary group in order to develop an alternative method for the installation and maintenance of steel mill equipment. In both examples, application of the OWAS method led to improved posture in the situations studied, and to the likelihood of its wider industrial use. PMID:15676393

  2. Reliable aerial thermography for energy conservation

    NASA Technical Reports Server (NTRS)

    Jack, J. R.; Bowman, R. L.

    1981-01-01

    A method for energy conservation, the aerial thermography survey, is discussed. It locates sources of energy losses and wasteful energy management practices. An operational map is presented for clear sky conditions. The map outlines the key environmental conditions conductive to obtaining reliable aerial thermography. The map is developed from defined visual and heat loss discrimination criteria which are quantized based on flat roof heat transfer calculations.

  3. Aerial righting reflexes in flightless animals.

    PubMed

    Jusufi, Ardian; Zeng, Yu; Full, Robert J; Dudley, Robert

    2011-12-01

    Animals that fall upside down typically engage in an aerial righting response so as to reorient dorsoventrally. This behavior can be preparatory to gliding or other controlled aerial behaviors and is ultimately necessary for a successful landing. Aerial righting reflexes have been described historically in various mammals such as cats, guinea pigs, rabbits, rats, and primates. The mechanisms whereby such righting can be accomplished depend on the size of the animal and on anatomical features associated with motion of the limbs and body. Here we apply a comparative approach to the study of aerial righting to explore the diverse strategies used for reorientation in midair. We discuss data for two species of lizards, the gecko Hemidactylus platyurus and the anole Anolis carolinensis, as well as for the first instar of the stick insect Extatosoma tiaratum, to illustrate size-dependence of this phenomenon and its relevance to subsequent aerial performance in parachuting and gliding animals. Geckos can use rotation of their large tails to reorient their bodies via conservation of angular momentum. Lizards with tails well exceeding snout-vent length, and correspondingly large tail inertia to body inertia ratios, are more effective at creating midair reorientation maneuvers. Moreover, experiments with stick insects, weighing an order of magnitude less than the lizards, suggest that aerodynamic torques acting on the limbs and body may play a dominant role in the righting process for small invertebrates. Both inertial and aerodynamic effects, therefore, can play a role in the control of aerial righting. We propose that aerial righting reflexes are widespread among arboreal vertebrates and arthropods and that they represent an important initial adaptation in the evolution of controlled aerial behavior. PMID:21930662

  4. Determination of characteristic parameters of human postural dynamics.

    PubMed

    Johansson, R; Magnusson, M

    1989-01-01

    Posture control performance was quantified in three variables (swiftness, stiffness, damping). Subjects were tested with a force platform recording body sway induced by vibrators attached to the calf muscles. Parameter estimation was made with identification of a transfer function representing the stabilized inverted pendulum. It is conjectured that the state feedback parameters identified are suitable for use in assessing ability to maintain posture. PMID:2635507

  5. Postural sway in diabetic peripheral neuropathy among Indian elderly

    PubMed Central

    Dixit, Snehil; Maiya, Arun; Shasthry, B.A.; Kumaran, D. Senthil; Guddattu, Vasudeva

    2015-01-01

    Background & objectives: Diabetic peripheral neuropathy (DPN) is a major complication of type 2 diabetes and have long term complications on the postural control of the affected population. The objectives of this study were to evaluate postural stability in patients with DPN and to examine correlation of Michigan Neuropathy Screening Instrument (MNSI) with duration of diabetes, age and postural stability measures. Methods: Participants were included if they had clinical neuropathy which was defined by MNSI. Sixty one patients gave their consent to participate in the study and were evaluated on posturography for postural stability measures in four conditions. Repeated measures of analysis of variance (RANOVA) was used to analyze the changes in postural stability measures in different conditions. Results: An increase in mean value of postural stability measures was observed for velocity moment 20.4±1.3, 24.3±2.2, 42.3±20.7, 59±43.03, mediolateral displacement 0.21±0.10, 0.22±0.18, 0.03±0.11, 0.34±0.18, and anteroposterior displacement 0.39 ± 0.09, 0.45±0.12, 0.47±0.13, 0.51±0.20 from EO to EC, EOF, and ECF, respectively. There was a significant difference (P<0.05) in participants with DPN, with greater sway amplitude on firm and foam surface in all the conditions. Moderate correlation of MNSI with age (r=0.43) and postural stability measures were also observed. Interpretation & conclusions: Evaluation of postural stability in Indian DPN population suggests balance impairments on either firm and foam surfaces, with greater likelihood of fall being on foam or deformable surfaces among elderly adults with neuropathy (CTRI/2011/07/001884). PMID:26831420

  6. Tai Chi training reduced coupling between respiration and postural control.

    PubMed

    Holmes, Matthew L; Manor, Brad; Hsieh, Wan-hsin; Hu, Kun; Lipsitz, Lewis A; Li, Li

    2016-01-01

    In order to maintain stable upright stance, the postural control system must account for the continuous perturbations to the body's center-of-mass including those caused by spontaneous respiration. Both aging and disease increase "posturo-respiratory synchronization;" which reflects the degree to which respiration affects postural sway fluctuations over time. Tai Chi training emphasizes the coordination of respiration and bodily movements and may therefore optimize the functional interaction between these two systems. The purpose of the project was to examine the effect of Tai Chi training on the interaction between respiration and postural control in older adults. We hypothesized that Tai Chi training would improve the ability of the postural control system to compensate for respiratory perturbations and thus, reduce posturo-respiratory synchronization. Participants were recruited from supportive housing facilities and randomized to a 12-week Tai Chi intervention (n=28; 86 ± 5 yrs) or educational-control program (n=34, 85 ± 6 yrs). Standing postural sway and respiration were simultaneously recorded with a force plate and respiratory belt under eyes-open and eyes-closed conditions. Posturo-respiratory synchronization was determined by quantifying the variation of the phase relationship between the dominant oscillatory mode of respiration and corresponding oscillations within postural sway. Groups were similar in age, gender distribution, height, body mass, and intervention compliance. Neither intervention altered average sway speed, sway magnitude or respiratory rate. As compared to the education-control group, however, Tai Chi training reduced posturo-respiratory synchronization when standing with eyes open or closed (p<0.001). Tai Chi training did not affect traditional parameters of standing postural control or respiration, yet reduced the coupling between respiration and postural control. The beneficial effects of Tai Chi training may therefore stem in part

  7. Biomechanical capabilities influence postural control strategies in the cat hindlimb

    PubMed Central

    McKay, J. Lucas; Burkholder, Thomas J.; Ting, Lena H.

    2008-01-01

    During postural responses to perturbations, horizontal plane forces generated by the cat hindlimb are stereotypically directed either towards or away from the animal’s center of mass, independent of perturbation direction. We used a static, three-dimensional musculoskeletal model of the hindlimb to investigate possible biomechanical determinants of this “force constraint strategy” (Macpherson, 1988). We hypothesized that directions in which the hindlimb can produce large forces are preferentially used in postural control. We computed feasible force sets (FFS) based on hindlimb configurations of three cats during postural equilibrium tasks (Jacobs and Macpherson, 1996) and compared them to horizontal plane postural force directions. The grand mean FFS was bimodal, with maxima near the posterior-anterior axis (−86±8° and 71±4°), and minima near the medial-lateral axis (177±8° and 8±8°). Postural force directions clustered near both maxima; there were no medial postural forces near the absolute minimum. However, the medians of the anterior and posterior postural force direction histograms in the right hindlimb were rotated counter-clockwise from the FFS maxima (p<0.05; Wilcoxon signed-rank test). Because the posterior-anterior alignment of the FFS is consistent with a hindlimb structure optimized for locomotion, we conclude that the biomechanical capabilities of the hindlimb strongly influence, but do not uniquely determine the force directions observed in the force constraint strategy. Forces used in postural control may reflect a balance between a neural preference for using forces in the directions of large feasible forces and other criteria, such as the stabilization of the center of mass, and muscular coordination strategies. PMID:17156787

  8. Association between temporomandibular disorders and abnormal head postures.

    PubMed

    Faulin, Evandro Francisco; Guedes, Carlos Gramani; Feltrin, Pedro Paulo; Joffiley, Cláudia Maria Mithie Suda Costa

    2015-01-01

    This study examines the possible correlation between the prevalence of temporomandibular disorders (TMD) and different head postures in the frontal and sagittal planes using photographs of undergraduate students in the School of Dentistry at the Universidade de Brasília - UnB, Brazil. In this nonrandomized, cross-sectional study, the diagnoses of TMD were made with the Research Diagnostic Criteria (RDC)/TMD axis I. The craniovertebral angle was used to evaluate forward head posture in the sagittal plane, and the interpupillary line was used to measure head tilt in the frontal plane. The measurements to evaluate head posture were made using the Software for the Assessment of Posture (SAPO). Students were divided into two study groups, based on the presence or absence of TMD. The study group comprised 46 students and the control group comprised 80 students. Data about head posture and TMD were analyzed with the Statistical Package for the Social Sciences, version 13. Most cases of TMD were classified as degenerative processes (group III), followed by disk displacement (group II) and muscle disorders (group I). There was no sex predominance for the type of disorder. No association was found between prevalence rates for head postures in the frontal plane and the occurrence of TMD. The same result was found for the association of TMD diagnosis with craniovertebral angle among men and women, and the group that contained both men and women. Abnormal head postures were common among individuals both with and without TMD. No association was found between head posture evaluated in the frontal and sagittal planes and TMD diagnosis with the use of RDC/TMD. PMID:26017489

  9. Human posture classification for intelligent visual surveillance systems

    NASA Astrophysics Data System (ADS)

    Rababaah, Haroun; Shirkhodaie, Amir

    2008-04-01

    Intelligent surveillance systems (ISS) have gained a significant attention in recent years due to the nationwide security concerns. Some of the important applications of ISS include: homeland security, border monitoring, battlefield intelligence, and sensitive facility monitoring. The essential requirements of an ISS include: (1) multi-modality multi-sensor data and information fusion, (2) communication networking, (3) distributed data/information processing,(4) Automatic target recognition and tracking, (5) Scenario profiling from discrete correlated/uncorrelated events, (6) Context-based situation reasoning, and (7) Collaborative resource sharing and decision support systems. In this paper we have addressed the problem of humanposture classification in crowded urban terrain environments. Certain range of human postures can be attributed to different suspicious acts of intruders in a constrained environment. By proper time analysis of human trespassers' postures in an environment, it would be possible to identify and differentiate malicious intention of the trespassers from other normal human behaviors. Specifically in this paper, we have proposed an image processing-based approach for characterization of five different human postures including: standing, bending, crawling, carrying a heavy object, and holding a long object. Two approaches were introduced to address the problem: template-matching and Hamming Adaptive Neural Network (HANN) classifiers. The former approach performs human posture characterization via binary-profile projection and applies a correlation-based method for classification of human postures. The latter approach is based a HANN technique. For training of the neural, the posture-patterns are initially compressed, thresholded, and serialized. The binary posture-pattern arrays were then used for training of the HANN. The comparative performance evaluation of both approaches the same set of training and testing examples were used to measure

  10. Real-time posture reconstruction for Microsoft Kinect.

    PubMed

    Shum, Hubert P H; Ho, Edmond S L; Jiang, Yang; Takagi, Shu

    2013-10-01

    The recent advancement of motion recognition using Microsoft Kinect stimulates many new ideas in motion capture and virtual reality applications. Utilizing a pattern recognition algorithm, Kinect can determine the positions of different body parts from the user. However, due to the use of a single-depth camera, recognition accuracy drops significantly when the parts are occluded. This hugely limits the usability of applications that involve interaction with external objects, such as sport training or exercising systems. The problem becomes more critical when Kinect incorrectly perceives body parts. This is because applications have limited information about the recognition correctness, and using those parts to synthesize body postures would result in serious visual artifacts. In this paper, we propose a new method to reconstruct valid movement from incomplete and noisy postures captured by Kinect. We first design a set of measurements that objectively evaluates the degree of reliability on each tracked body part. By incorporating the reliability estimation into a motion database query during run time, we obtain a set of similar postures that are kinematically valid. These postures are used to construct a latent space, which is known as the natural posture space in our system, with local principle component analysis. We finally apply frame-based optimization in the space to synthesize a new posture that closely resembles the true user posture while satisfying kinematic constraints. Experimental results show that our method can significantly improve the quality of the recognized posture under severely occluded environments, such as a person exercising with a basketball or moving in a small room. PMID:23981562

  11. Changes in Habitual and Active Sagittal Posture in Children and Adolescents with and without Visual Input – Implications for Diagnostic Analysis of Posture

    PubMed Central

    Mazet, Carola; Mazet, Dirk; Hammes, Annette; Schmitt, Eduard

    2016-01-01

    Introduction Poor posture in children and adolescents has a prevalence of 22-65% and is suggested to be responsible for back pain. To assess posture, photometric imaging of sagittal posture is widely used, but usually only habitual posture positions (resting position with minimal muscle activity) are analysed. Aim The objective of this study was 1) to investigate possible changes in posture-describing parameters in the sagittal plane, when the subjects changed from a habitual passive posture to an actively corrected posture, and 2) to investigate the changes in posture parameters when an actively corrected posture was to be maintained with closed eyes. Materials and Methods In a group of 216 male children and adolescents (average 12.4 ± 2.5 years, range 7.0 – 17.6 years), six sagittal posture parameters (body tilt BT, trunk incline TI, posture index PI, horizontal distances between ear, shoulder and hip and the perpendicular to the ankle joint) were determined by means of photometric imaging in an habitual passive posture position, in an actively erect posture with eyes open, and in active stance with eyes closed. The change in these parameters during the transition between the posture positions was analysed statistically (dependent t-Test or Wilcoxon-Test) after Bonferroni correction (p<0.004). Results When moving from a habitual passive to an active posture BT, TI, PI, dEar, dShoulder, and dHip decreased significantly(p< 0.004). When the eyes were closed, only the perpendicular distances (dEar, dShoulder, and dHip) increased significantly. The parameters that describe the alignment of the trunk sections in relation to each other (BT, TI, PI), remained unchanged in both actively regulated posture positions. Conclusion Changes in sagittal posture parameters that occur when a habitual passive posture switches into an active posture or when an active posture is to be maintained while the eyes are closed can be used for diagnostic purposes regarding poor posture

  12. Endurance bounds of aerial systems

    NASA Astrophysics Data System (ADS)

    Harrington, Aaron M.; Kroninger, Christopher M.

    2014-06-01

    Within the past few years micro aerial vehicles (MAVs) have received much more attention and are starting to proliferate into military as well as civilian roles. However, one of the major drawbacks for this technology currently, has been their poor endurance, usually below 10 minutes. This is a direct result of the inefficiencies inherent in their design. Often times, designers do not consider the various components in the vehicle design and match their performance to the desired mission for the vehicle. These vehicles lack a prescribed set of design guidelines or empirically derived design equations which often limits their design to selection of commercial off-the-shelf components without proper consideration of their affect on vehicle performance. In the current study, the design space for different vehicle configurations has been examined including insect flapping, avian flapping, rotary wing, and fixed wing, and their performance bounds are established. The propulsion system typical of a rotary wing vehicle is analyzed to establish current baselines for efficiency of vehicles at this scale. The power draw from communications is analyzed to determine its impact on vehicle performance. Finally, a representative fixed wing MAV is examined and the effects of adaptive structures as a means for increasing vehicle endurance and range are examined. This paper seeks to establish the performance bounds for micro air vehicles and establish a path forward for future designs so that efficiency may be maximized.

  13. Evaluating sensory conflict and postural instability. Theories of motion sickness.

    PubMed

    Warwick-Evans, L A; Symons, N; Fitch, T; Burrows, L

    1998-11-15

    Two experiments were carried out to evaluate the sensory conflict and the postural instability theories of motion sickness. The central hypothesis of sensory conflict theory is that motion sickness is caused by conflict between the current pattern of sensory inputs about self-movement and the pattern that is expected on the basis of previous experience. A subsidiary hypothesis is that the degree of motion sickness is proportional to the magnitude of sensory conflict. The central hypothesis of postural instability theory is that motion sickness is caused by loss of postural control. A subsidiary hypothesis is that the degree of motion sickness is proportional to amount of postural instability, which can be manipulated by physical restraint. In both experiments there were two levels of sensory conflict and two levels of postural restraint. Dependent variables were latency of onset and severity of motion sickness. The widespread occurrence of motion sickness in both experiments clearly confirmed the main hypothesis of sensory conflict theory. The results from Experiment 1, that there was significantly more motion sickness in the restrained condition, and from Experiment 2, that there was no significant difference in symptoms between the two restraint conditions, provide no support for the subsidiary hypothesis of postural instability theory. Evidence relating to the subsidiary proposition of sensory conflict theory was inconsistent. PMID:10052575

  14. Adaptability of anticipatory postural adjustments associated with voluntary movement

    PubMed Central

    Yiou, Eric; Caderby, Teddy; Hussein, Tarek

    2012-01-01

    The control of balance is crucial for efficiently performing most of our daily motor tasks, such as those involving goal-directed arm movements or whole body displacement. The purpose of this article is twofold. Firstly, it is to recall how balance can be maintained despite the different sources of postural perturbation arising during voluntary movement. The importance of the so-called “anticipatory postural adjustments” (APA), taken as a “line of defence” against the destabilizing effect induced by a predicted perturbation, is emphasized. Secondly, it is to report the results of recent studies that questioned the adaptability of APA to various constraints imposed on the postural system. The postural constraints envisaged here are classified into biomechanical (postural stability, superimposition of motor tasks), (neuro) physiological (fatigue), temporal (time pressure) and psychological (fear of falling, emotion). Overall, the results of these studies point out the capacity of the central nervous system (CNS) to adapt the spatio-temporal features of APA to each of these constraints. However, it seems that, depending on the constraint, the “priority” of the CNS was focused on postural stability maintenance, on body protection and/or on maintenance of focal movement performance. PMID:22720267

  15. Effects of acute spinalization on neurons of postural networks

    PubMed Central

    Zelenin, Pavel V.; Lyalka, Vladimir F.; Hsu, Li-Ju; Orlovsky, Grigori N.; Deliagina, Tatiana G.

    2016-01-01

    Postural limb reflexes (PLRs) represent a substantial component of postural corrections. Spinalization results in loss of postural functions, including disappearance of PLRs. The aim of the present study was to characterize the effects of acute spinalization on two populations of spinal neurons (F and E) mediating PLRs, which we characterized previously. For this purpose, in decerebrate rabbits spinalized at T12, responses of interneurons from L5 to stimulation causing PLRs before spinalization, were recorded. The results were compared to control data obtained in our previous study. We found that spinalization affected the distribution of F- and E-neurons across the spinal grey matter, caused a significant decrease in their activity, as well as disturbances in processing of posture-related sensory inputs. A two-fold decrease in the proportion of F-neurons in the intermediate grey matter was observed. Location of populations of F- and E-neurons exhibiting significant decrease in their activity was determined. A dramatic decrease of the efficacy of sensory input from the ipsilateral limb to F-neurons, and from the contralateral limb to E-neurons was found. These changes in operation of postural networks underlie the loss of postural control after spinalization, and represent a starting point for the development of spasticity. PMID:27302149

  16. Subjective Visual Vertical and Postural Capability in Children Born Prematurely

    PubMed Central

    Bucci, Maria Pia; Wiener-Vacher, Sylvette; Trousson, Clémence; Baud, Olivier; Biran, Valerie

    2015-01-01

    Purpose We compared postural stability and subjective visual vertical performance in a group of very preterm-born children aged 3-4 years and in a group of age-matched full-term children. Materials and Methods A platform (from TechnoConcept) was used to measure postural control in children. Perception of subjective visual vertical was also recorded with posture while the child had to adjust the vertical in the dark or with visual perturbation. Two other conditions (control conditions) were also recorded while the child was on the platform: for a fixation of the vertical bar, and in eyes closed condition. Results Postural performance was poor in preterm-born children compared to that of age-matched full-term children: the surface area, the length in medio-lateral direction and the mean speed of the center of pressure (CoP) were significantly larger in the preterm-born children group (p < 0.04, p < 0.01, and p < 0.04, respectively). Dual task in both groups of children significantly affected postural control. The subjective visual vertical (SVV) values were more variable and less precise in preterm-born children. Discussion-Conclusions We suggest that poor postural control as well as perception of verticality observed in preterm-born children could be due to immaturity of the cortical processes involved in the motor control and in the treatment of perception and orientation of verticality. PMID:25790327

  17. Monitoring the prevalence of postural changes in schoolchildren

    PubMed Central

    Nichele da Rosa, Bruna; Noll, Matias; Sedrez, Juliana Adami; Furlanetto, Tassia Silveira; Candotti, Claudia Tarrago

    2016-01-01

    [Purpose] The aim of this study was to identify whether postural changes are prevalent with advancing age using a photogrammetric method performing one-year follow-up study. [Subjects and Methods] Thirty-eight schoolchildren were evaluated in 2011 and 2012 in this cohort study. The subjects underwent a postural evaluation, which involved palpation of reference anatomic points, placement of reflexive markers over the anatomic points, image acquisition, and point digitalization using the Digital Image-based Postural Assessment evaluation software. For data analysis, descriptive statistics and inferential statistics were analyzed by McNemar’s test. [Results] The results showed a significant increase in postural change prevalence for the lumbar spine in the sagittal plane (from 42.2% to 81.6%) and the knees in the frontal plane (from 39.5% to 63.2%) and a significant decrease in the prevalence of scoliosis (from 68.5% to 42.2%). [Conclusion] The findings indicate an increase in the prevalence of postural changes in schoolchildren from Teutônia, RS, Brazil, in 2012 compared with 2011. The development of longitudinal investigations for long-term monitoring of the evolution of posture and of schoolchildren habits’s representing a viable alternative to subsidize health actions. PMID:27065514

  18. Postured voxel-based human models for electromagnetic dosimetry

    NASA Astrophysics Data System (ADS)

    Nagaoka, Tomoaki; Watanabe, Soichi

    2008-12-01

    High-resolution anatomically realistic whole-body voxel models have recently been developed for electromagnetic dosimetry. However, the posture of most models is similar to the standing one, which strongly limits electromagnetic dosimetry when simulating a realistic exposure scenario. In this paper, we present the development of postured models based on anatomically realistic voxel models with standing posture. Voxel models of the Japanese adult male and female were used as the original upright standing models. The Japanese models were composed of 2 mm cubic voxels, each of which was segmented into 51 different tissue types. We developed several different types of posture models using a novel posture transformation method. These posture models were smoothly transformed, while the continuity of the internal tissues and organs was maintained. In this paper, we also present our calculations of the whole-body averaged specific absorption rates (SARs) of sitting male and female models exposed to electromagnetic plane waves at very high (VHF) and ultra high frequency (UHF) bands.

  19. "Stand up straight": notes toward a history of posture.

    PubMed

    Gilman, Sander L

    2014-03-01

    The essay presents a set of interlinked claims about posture in modern culture. Over the past two centuries it has come to define a wide range of assumptions in the West from what makes human beings human (from Lamarck to Darwin and beyond) to the efficacy of the body in warfare (from Dutch drill manuals in the 17th century to German military medical studies of soldiers in the 19th century). Dance and sport both are forms of posture training in terms of their own claims. Posture separates 'primitive' from 'advanced' peoples and the 'ill' from the 'healthy.' Indeed an entire medical sub-specialty developed in which gymnastics defined and recuperated the body. But all of these claims were also part of a Western attempt to use posture (and the means of altering it) as the litmus test for the healthy modern body of the perfect citizen. Focusing on the centrality of posture in two oddly linked moments of modern thought--modern Zionist thought and Nationalism in early 20th century China--in terms of bodily reform, we show how "posture" brings all of the earlier debates together to reform the body. PMID:24317755

  20. The Relationship Between the Stomatognathic System and Body Posture

    PubMed Central

    Cuccia, Antonino; Caradonna, Carola

    2009-01-01

    In recent years, many researchers have investigated the various factors that can influence body posture: mood states, anxiety, head and neck positions, oral functions (respiration, swallowing), oculomotor and visual systems, and the inner ear. Recent studies indicate a role for trigeminal afferents on body posture, but this has not yet been demonstrated conclusively. The present study aims to review the papers that have shown a relationship between the stomatognathic system and body posture. These studies suggest that tension in the stomatognathic system can contribute to impaired neural control of posture. Numerous anatomical connections between the stomatognathic system’s proprioceptive inputs and nervous structures are implicated in posture (cerebellum, vestibular and oculomotor nuclei, superior colliculus). If the proprioceptive information of the stomatognathic system is inaccurate, then head control and body position may be affected. In addition, the present review discusses the role the myofascial system plays in posture. If confirmed by further research, these considerations can improve our understanding and treatment of muscular-skeletal disorders that are associated with temporomandibular joint disorders, occlusal changes, and tooth loss. PMID:19142553

  1. The relationship between the stomatognathic system and body posture.

    PubMed

    Cuccia, Antonino; Caradonna, Carola

    2009-01-01

    In recent years, many researchers have investigated the various factors that can influence body posture: mood states, anxiety, head and neck positions, oral functions (respiration, swallowing), oculomotor and visual systems, and the inner ear. Recent studies indicate a role for trigeminal afferents on body posture, but this has not yet been demonstrated conclusively. The present study aims to review the papers that have shown a relationship between the stomatognathic system and body posture. These studies suggest that tension in the stomatognathic system can contribute to impaired neural control of posture. Numerous anatomical connections between the stomatognathic system's proprioceptive inputs and nervous structures are implicated in posture (cerebellum, vestibular and oculomotor nuclei, superior colliculus). If the proprioceptive information of the stomatognathic system is inaccurate, then head control and body position may be affected. In addition, the present review discusses the role the myofascial system plays in posture. If confirmed by further research, these considerations can improve our understanding and treatment of muscular-skeletal disorders that are associated with temporomandibular joint disorders, occlusal changes, and tooth loss. PMID:19142553

  2. Effects of acute spinalization on neurons of postural networks.

    PubMed

    Zelenin, Pavel V; Lyalka, Vladimir F; Hsu, Li-Ju; Orlovsky, Grigori N; Deliagina, Tatiana G

    2016-01-01

    Postural limb reflexes (PLRs) represent a substantial component of postural corrections. Spinalization results in loss of postural functions, including disappearance of PLRs. The aim of the present study was to characterize the effects of acute spinalization on two populations of spinal neurons (F and E) mediating PLRs, which we characterized previously. For this purpose, in decerebrate rabbits spinalized at T12, responses of interneurons from L5 to stimulation causing PLRs before spinalization, were recorded. The results were compared to control data obtained in our previous study. We found that spinalization affected the distribution of F- and E-neurons across the spinal grey matter, caused a significant decrease in their activity, as well as disturbances in processing of posture-related sensory inputs. A two-fold decrease in the proportion of F-neurons in the intermediate grey matter was observed. Location of populations of F- and E-neurons exhibiting significant decrease in their activity was determined. A dramatic decrease of the efficacy of sensory input from the ipsilateral limb to F-neurons, and from the contralateral limb to E-neurons was found. These changes in operation of postural networks underlie the loss of postural control after spinalization, and represent a starting point for the development of spasticity. PMID:27302149

  3. Evidence from the eyes: Threatening postures hold attention.

    PubMed

    Azarian, Bobby; Esser, Elizabeth G; Peterson, Matthew S

    2016-06-01

    Efficient detection of threat provides obvious survival advantages and has resulted in a fast and accurate threat-detection system. Although beneficial under normal circumstances, this system may become hypersensitive and cause threat-processing abnormalities. Past research has shown that anxious individuals have difficulty disengaging attention from threatening faces, but it is unknown whether other forms of threatening social stimuli also influence attentional orienting. Much like faces, human body postures are salient social stimuli, because they are informative of one's emotional state and next likely action. Additionally, postures can convey such information in situations in which another's facial expression is not easily visible. Here we investigated whether there is a threat-specific effect for high-anxious individuals, by measuring the time that it takes the eyes to leave the attended stimulus, a task-irrelevant body posture. The results showed that relative to nonthreating postures, threat-related postures hold attention in anxious individuals, providing further evidence of an anxiety-related attentional bias for threatening information. This is the first study to demonstrate that attentional disengagement from threatening postures is affected by emotional valence in those reporting anxiety. PMID:26384994

  4. Postural strategy changes with fatigue of the lumbar extensor muscles.

    PubMed

    Wilson, Erin L; Madigan, Michael L; Davidson, Bradley S; Nussbaum, Maury A

    2006-04-01

    The purpose of this study was to investigate the effect of lumbar extensor fatigue on postural strategy in response to a balance perturbation. Anteriorly-directed force perturbations were applied to the upper back with a padded pendulum and attempted to challenge the postural control system without eliciting a stepping response. In three separate sessions, subjects were perturbed both before and after a fatiguing protocol that induced lumbar extensor fatigue to one of three different fatigue levels. Postural strategy was quantified using center of pressure position along with joint angles and joint torques for the ankle, knee, hip, and "low back" joints. Results showed both proactive and reactive changes in postural strategy. Proactive changes involved a slight anterior lean prior to the perturbation, and reactive changes were consistent with a shift toward more of a hip strategy with fatigue. In addition, results suggested that subjects classified as moving mostly at the hip prior to fatigue were more affected by fatigue compared to subjects classified as moving roughly equal amounts at the ankle and hip prior to fatigue. Increasing fatigue level exaggerated some, but not all, of the changes in postural strategy with fatigue. These findings illustrate that neuromuscular fatigue can influence postural strategy in response to a balance perturbation. PMID:16023345

  5. Effects of Levodopa on Postural Strategies in Parkinson's disease.

    PubMed

    Baston, Chiara; Mancini, Martina; Rocchi, Laura; Horak, Fay

    2016-05-01

    Altered postural control and balance are major disabling issues of Parkinson's disease (PD). Static and dynamic posturography have provided insight into PD's postural deficits; however, little is known about impairments in postural coordination. We hypothesized that subjects with PD would show more ankle strategy during quiet stance than healthy control subjects, who would include some hip strategy, and this stiffer postural strategy would increase with disease progression. We quantified postural strategy and sway dispersion with inertial sensors (one placed on the shank and one on the posterior trunk at L5 level) while subjects were standing still with their eyes open. A total of 70 subjects with PD, including a mild group (H&Y≤2, N=33) and a more severe group (H&Y≥3, N=37), were assessed while OFF and while ON levodopa medication. We also included a healthy control group (N=21). Results showed an overall preference of ankle strategy in all groups while maintaining balance. Postural strategy was significantly lower ON compared to OFF medication (indicating more hip strategy), but no effect of disease stage was found. Instead, sway dispersion was significantly larger in ON compared to OFF medication, and significantly larger in the more severe PD group compared to the mild. In addition, increased hip strategy during stance was associated with poorer self-perception of balance. PMID:27131172

  6. Which biomechanical models are currently used in standing posture analysis?

    PubMed

    Crétual, A

    2015-11-01

    In 1995, David Winter concluded that postural analysis of upright stance was often restricted to studying the trajectory of the center of pressure (CoP). However, postural control means regulation of the center of mass (CoM) with respect to CoP. As CoM is only accessible by using a biomechanical model of the human body, the present article proposes to determine which models are actually used in postural analysis, twenty years after Winter's observation. To do so, a selection of 252 representative articles dealing with upright posture and published during the four last years has been checked. It appears that the CoP model largely remains the most common one (accounting for nearly two thirds of the selection). Other models, CoP/CoM and segmental models (with one, two or more segments) are much less used. The choice of the model does not appear to be guided by the population studied. Conversely, while some confusion remains between postural control and the associated concepts of stability or strategy, this choice is better justified for real methodological concerns when dealing with such high-level parameters. Finally, the computation of the CoM continues to be a limitation in achieving a more complete postural analysis. This unfortunately implies that the model is chosen for technological reasons in many cases (choice being a euphemism here). Some effort still has to be made so that bioengineering developments allow us to go beyond this limit. PMID:26388359

  7. Otolith and Vertical Canal Contributions to Dynamic Postural Control

    NASA Technical Reports Server (NTRS)

    Black, F. Owen

    1999-01-01

    The objective of this project is to determine: 1) how do normal subjects adjust postural movements in response to changing or altered otolith input, for example, due to aging? and 2) how do patients adapt postural control after altered unilateral or bilateral vestibular sensory inputs such as ablative inner ear surgery or ototoxicity, respectively? The following hypotheses are under investigation: 1) selective alteration of otolith input or abnormalities of otolith receptor function will result in distinctive spatial, frequency, and temporal patterns of head movements and body postural sway dynamics. 2) subjects with reduced, altered, or absent vertical semicircular canal receptor sensitivity but normal otolith receptor function or vice versa, should show predictable alterations of body and head movement strategies essential for the control of postural sway and movement. The effect of altered postural movement control upon compensation and/or adaptation will be determined. These experiments provide data for the development of computational models of postural control in normals, vestibular deficient subjects and normal humans exposed to unusual force environments, including orbital space flight.

  8. Use of Video Analysis System for Working Posture Evaluations

    NASA Technical Reports Server (NTRS)

    McKay, Timothy D.; Whitmore, Mihriban

    1994-01-01

    In a work environment, it is important to identify and quantify the relationship among work activities, working posture, and workplace design. Working posture may impact the physical comfort and well-being of individuals, as well as performance. The Posture Video Analysis Tool (PVAT) is an interactive menu and button driven software prototype written in Supercard (trademark). Human Factors analysts are provided with a predefined set of options typically associated with postural assessments and human performance issues. Once options have been selected, the program is used to evaluate working posture and dynamic tasks from video footage. PVAT has been used to evaluate postures from Orbiter missions, as well as from experimental testing of prototype glove box designs. PVAT can be used for video analysis in a number of industries, with little or no modification. It can contribute to various aspects of workplace design such as training, task allocations, procedural analyses, and hardware usability evaluations. The major advantage of the video analysis approach is the ability to gather data, non-intrusively, in restricted-access environments, such as emergency and operation rooms, contaminated areas, and control rooms. Video analysis also provides the opportunity to conduct preliminary evaluations of existing work areas.

  9. Monitoring the prevalence of postural changes in schoolchildren.

    PubMed

    Nichele da Rosa, Bruna; Noll, Matias; Sedrez, Juliana Adami; Furlanetto, Tassia Silveira; Candotti, Claudia Tarrago

    2016-01-01

    [Purpose] The aim of this study was to identify whether postural changes are prevalent with advancing age using a photogrammetric method performing one-year follow-up study. [Subjects and Methods] Thirty-eight schoolchildren were evaluated in 2011 and 2012 in this cohort study. The subjects underwent a postural evaluation, which involved palpation of reference anatomic points, placement of reflexive markers over the anatomic points, image acquisition, and point digitalization using the Digital Image-based Postural Assessment evaluation software. For data analysis, descriptive statistics and inferential statistics were analyzed by McNemar's test. [Results] The results showed a significant increase in postural change prevalence for the lumbar spine in the sagittal plane (from 42.2% to 81.6%) and the knees in the frontal plane (from 39.5% to 63.2%) and a significant decrease in the prevalence of scoliosis (from 68.5% to 42.2%). [Conclusion] The findings indicate an increase in the prevalence of postural changes in schoolchildren from Teutônia, RS, Brazil, in 2012 compared with 2011. The development of longitudinal investigations for long-term monitoring of the evolution of posture and of schoolchildren habits's representing a viable alternative to subsidize health actions. PMID:27065514

  10. A New Standing Posture Detector to Enable People with Multiple Disabilities to Control Environmental Stimulation by Changing Their Standing Posture through a Commercial Wii Balance Board

    ERIC Educational Resources Information Center

    Shih, Ching-Hsiang; Shih, Ching-Tien; Chiang, Ming-Shan

    2010-01-01

    This study assessed whether two persons with multiple disabilities would be able to control environmental stimulation using body swing (changing standing posture) and a Wii Balance Board with a newly developed standing posture detection program (i.e. a new software program turns a Wii Balance Board into a precise standing posture detector). The…

  11. Effects of disease severity and medication state on postural control asymmetry during challenging postural tasks in individuals with Parkinson's disease.

    PubMed

    Barbieri, Fabio A; Polastri, Paula F; Baptista, André M; Lirani-Silva, Ellen; Simieli, Lucas; Orcioli-Silva, Diego; Beretta, Victor S; Gobbi, Lilian T B

    2016-04-01

    The aim of this study was to investigate the effects of disease severity and medication state on postural control asymmetry during challenging tasks in individuals with Parkinson's disease (PD). Nineteen people with PD and 11 neurologically healthy individuals performed three standing task conditions: bipedal standing, tandem and unipedal adapted standing; the individuals with PD performed the tasks in ON and OFF medication state. The participants with PD were distributed into 2 groups according to disease severity: unilateral group (n=8) and bilateral group (n=11). The two PD groups performed the evaluations both under and without the medication. Two force plates were used to analyze the posture. The symmetric index was calculated for various of center of pressure. ANOVA one-way (groups) and two-way (PD groups×medication), with repeated measures for medication, were calculated. For main effects of group, the bilateral group was more asymmetric than CG. For main effects of medication, only unipedal adapted standing presented effects of PD medication. There was PD groups×medication interaction. Under the effects of medication, the unilateral group presented lower asymmetry of RMS in anterior-posterior direction and area than the bilateral group in unipedal adapted standing. In addition, the unilateral group presented lower asymmetry of mean velocity, RMS in anterior-posterior direction and area in unipedal standing and area in tandem adapted standing after a medication dose. Postural control asymmetry during challenging postural tasks was dependent on disease severity and medication state in people with PD. The bilateral group presented higher postural control asymmetry than the control and unilateral groups in challenging postural tasks. Finally, the medication dose was able to reduce postural control asymmetry in the unilateral group during challenging postural tasks. PMID:26741255

  12. Influence of Sensory Dependence on Postural Control

    NASA Technical Reports Server (NTRS)

    Santana, Patricia A.; Mulavara, Ajitkumar P.; Fiedler, Matthew J.

    2011-01-01

    The current project is part of an NSBRI funded project, "Development of Countermeasures to Aid Functional Egress from the Crew Exploration Vehicle Following Long-Duration Spaceflight." The development of this countermeasure is based on the use of imperceptible levels of electrical stimulation to the balance organs of the inner ear to assist and enhance the response of a person s sensorimotor function. These countermeasures could be used to increase an astronaut s re-adaptation rate to Earth s gravity following long-duration space flight. The focus of my project is to evaluate and examine the correlation of sensory preferences for vision and vestibular systems. Disruption of the sensorimotor functions following space flight affects posture, locomotion and spatial orientation tasks in astronauts. The Group Embedded Figures Test (GEFT), the Rod and Frame Test (RFT) and the Computerized Dynamic Posturography Test (CDP) are measurements used to examine subjects visual and vestibular sensory preferences. The analysis of data from these tasks will assist in relating the visual dependence measures recognized in the GEFT and RFT with vestibular dependence measures recognized in the stability measures obtained during CDP. Studying the impact of sensory dependence on the performance in varied tasks will help in the development of targeted countermeasures to help astronauts readapt to gravitational changes after long duration space flight.

  13. Idiopathic orthostatic intolerance and postural tachycardia syndromes

    NASA Technical Reports Server (NTRS)

    Jacob, G.; Biaggioni, I.; Robertson, D. (Principal Investigator)

    1999-01-01

    Upright posture imposes a substantial gravitational stress on the body, for which we are able to compensate, in large part because of the autonomic nervous system. Alteration in autonomic function, therefore, may lead to orthostatic intolerance. On one extreme, patients with autonomic failure caused by degenerative loss of autonomic function are severely disabled by orthostatic hypotension and may faint whenever they stand up. Fortunately, such patients are relatively rare. On the other hand, disabling orthostatic intolerance can develop in otherwise normal young people. These patients can be severely impaired by symptoms of fatigue, tachycardia, and shortness of breath when they stand up. The actual incidence of this disorder is unknown, but these patients make up the largest group of patients referred to centers that specialize in autonomic disorders. We will review recent advances made in the understanding of this condition, potential pathophysiological mechanisms that contribute to orthostatic intolerance, therapeutic alternatives currently available for the management of these patients, and areas in which more research is needed.

  14. Neuromuscular dentistry: Occlusal diseases and posture.

    PubMed

    Khan, Mohd Toseef; Verma, Sanjeev Kumar; Maheshwari, Sandhya; Zahid, Syed Naved; Chaudhary, Prabhat K

    2013-01-01

    Neuromuscular dentistry has been a controversial topic in the field of dentistry and still remains debatable. The issue of good occlusion and sound health has been repeatedly discussed. Sometimes we get complains of sensitive teeth and sometimes of tired facial muscles on getting up in the morning. Owing to the intimate relation of masticatory apparatus with the cranium and cervico-scapular muscular system, the disorders in any system, draw attention from concerned clinicians involved in management, to develop an integrated treatment protocol for the suffering patients. There may be patients reporting to the dental clinics after an occlusal restoration or extraction, having pain in or around the temporomandibular joint, headache or neck pain. Although their esthetic demands must not be undermined during the course of treatment plan, whenever dental treatment of any sort is planned, occlusion/bite should be given prime importance. Very few dentist are able to diagnose the occlusal disease and of those who diagnose many people resort to aggressive treatment modalities. This paper aims to report the signs of occlusal disease, and discuss their association with TMDs and posture. PMID:25737904

  15. Aerial photo SBVC1962". Photo no. 360. Low oblique aerial view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Aerial photo -SBVC-1962". Photo no. 360. Low oblique aerial view of the campus, looking southeast. Stamped on the rear: "Ron Wilhite, Sun-Telegram photo, file, 10/22/62/ - San Bernardino Valley College, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  16. Cerebellar control of postural scaling and central set in stance.

    PubMed

    Horak, F B; Diener, H C

    1994-08-01

    1. The effects of cerebellar deficits in humans on scaling the magnitude of automatic postural responses based on sensory feedback and on predictive central set was investigated. Electromyographic (EMG) and surface reactive torques were compared in patients with anterior lobe cerebellar disorders and in normal healthy adults exposed to blocks of four velocities and five amplitudes of surface translations during stance. Correlations between the earliest postural responses (integrated EMG and initial rate of change of torque) and translation velocity provided a measure of postural magnitude scaling using sensory information from the current displacement. Correlations of responses with translation amplitude provided a measure of scaling dependent on predictive central set based on sequential experience with previous like displacements because the earliest postural responses occurred before completion of the displacements and because scaling to displacement amplitude disappeared when amplitudes were randomized in normal subjects. 2. Responses of cerebellar patients to forward body sway induced by backward surface displacements were hypermetric, that is, surface-reactive torque responses were two to three times larger than normal with longer muscle bursts resulting in overshooting of initial posture. Despite this postural hypermetria, the absolute and relative latencies of agonist muscle bursts at the ankle, knee, and hip were normal in cerebellar patients. 3. Although they were hypermetric, the earliest postural responses of cerebellar patients were scaled normally to platform displacement velocities using somatosensory feedback. Cerebellar patients, however, were unable to scale initial postural response magnitude to expected displacement amplitudes based on prior experience using central set. Randomization of displacement amplitudes eliminated the set effect of amplitude on initial responses in normal subjects, but responses to randomized and blocked trials were not

  17. Real-Time Hand Posture Recognition Using a Range Camera

    NASA Astrophysics Data System (ADS)

    Lahamy, Herve

    The basic goal of human computer interaction is to improve the interaction between users and computers by making computers more usable and receptive to the user's needs. Within this context, the use of hand postures in replacement of traditional devices such as keyboards, mice and joysticks is being explored by many researchers. The goal is to interpret human postures via mathematical algorithms. Hand posture recognition has gained popularity in recent years, and could become the future tool for humans to interact with computers or virtual environments. An exhaustive description of the frequently used methods available in literature for hand posture recognition is provided. It focuses on the different types of sensors and data used, the segmentation and tracking methods, the features used to represent the hand postures as well as the classifiers considered in the recognition process. Those methods are usually presented as highly robust with a recognition rate close to 100%. However, a couple of critical points necessary for a successful real-time hand posture recognition system require major improvement. Those points include the features used to represent the hand segment, the number of postures simultaneously recognizable, the invariance of the features with respect to rotation, translation and scale and also the behavior of the classifiers against non-perfect hand segments for example segments including part of the arm or missing part of the palm. A 3D time-of-flight camera named SR4000 has been chosen to develop a new methodology because of its capability to provide in real-time and at high frame rate 3D information on the scene imaged. This sensor has been described and evaluated for its capability for capturing in real-time a moving hand. A new recognition method that uses the 3D information provided by the range camera to recognize hand postures has been proposed. The different steps of this methodology including the segmentation, the tracking, the hand

  18. Postural Rehabilitation for Adolescent Idiopathic Scoliosis during Growth

    PubMed Central

    Weiss, Hans-Rudolf; Moramarco, Marc Michael; Borysov, Maksym; Lee, Sang Gil; Nan, Xiaofeng; Moramarco, Kathryn Ann

    2016-01-01

    Long-term follow-up of untreated patients with adolescent idiopathic scoliosis (AIS) indicates that, with the exception of some extremely severe cases, AIS does not have a significant impact on quality of life and does not result in dire consequences. In view of the relatively benign nature of AIS and the long-term complications of surgery, the indications for treatment should be reviewed. Furthermore, recent studies have shown that scoliosis-specific exercises focusing on postural rehabilitation can positively influence the spinal curvatures in growing adolescents. Experiential postural re-education is a conservative, non-invasive approach, and its role in the management of AIS warrants further study. This article reviews current evidence for the inclusion of various forms of postural reeducation in the management of AIS. Recent comprehensive reviews have been researched including a manual and PubMed search for evidence regarding the effectiveness of physical/postural re-education/physiotherapy programs in growing AIS patients. This search revealed that there were few studies on the application of postural re-education in the management of AIS. These studies revealed that postural re-education in the form of exercise rehabilitation programs may have a positive influence on scoliosis; however, the various programs were difficult to compare. More research is necessary. There is at present Level 1 evidence for the effectiveness of Schroth scoliosis exercises in the management of AIS. Whether this evidence can be extrapolated to include other forms of scoliosis- pattern-specific exercises requires further investigation. Because corrective postures theoretically reduce the asymmetric loading of the spinal deformities and reverse the vicious cycle of spinal curvature progression, their integration into AIS programs may be beneficial and should be further examined. PMID:27340540

  19. One month of contemporary dance modulates fractal posture in aging

    PubMed Central

    Coubard, Olivier A.; Ferrufino, Lena; Nonaka, Tetsushi; Zelada, Oscar; Bril, Blandine; Dietrich, Gilles

    2013-01-01

    Understanding the human aging of postural control and how physical or motor activity improves balance and gait is challenging for both clinicians and researchers. Previous studies have evidenced that physical and sporting activity focusing on cardiovascular and strength conditioning help older adults develop their balance and gait and/or decrease their frequency of falls. Motor activity based on motor-skill learning has also been put forward as an alternative to develop balance and/or prevent falls in aging. Specifically dance has been advocated as a promising program to boost motor control. In this study, we examined the effects of contemporary dance (CD) on postural control of older adults. Upright stance posturography was performed in 38 participants aged 54–89 years before and after the intervention period, during which one half of the randomly assigned participants was trained to CD and the other half was not trained at all (no dance, ND). CD training lasted 4 weeks, 3 times a week. We performed classical statistic scores of postural signal and dynamic analyses, namely signal diffusion analysis (SDA), recurrence quantification analysis (RQA), and detrended fluctuation analysis (DFA). CD modulated postural control in older trainees, as revealed in the eyes closed condition by a decrease in fractal dimension and an increase in DFA alpha component in the mediolateral plane. The ND group showed an increase in length and mean velocity of postural signal, and the eyes open a decrease in RQA maximal diagonal line in the anteroposterior plane and an increase in DFA alpha component in the mediolateral plane. No change was found in SDA in either group. We suggest that such a massed practice of CD reduced the quantity of exchange between the subject and the environment by increasing their postural confidence. Since CD has low-physical but high-motor impact, we conclude that it may be recommended as a useful program to rehabilitate posture in aging. PMID:24611047

  20. Development of adaptive sensorimotor control in infant sitting posture.

    PubMed

    Chen, Li-Chiou; Jeka, John; Clark, Jane E

    2016-03-01

    A reliable and adaptive relationship between action and perception is necessary for postural control. Our understanding of how this adaptive sensorimotor control develops during infancy is very limited. This study examines the dynamic visual-postural relationship during early development. Twenty healthy infants were divided into 4 developmental groups (each n=5): sitting onset, standing alone, walking onset, and 1-year post-walking. During the experiment, the infant sat independently in a virtual moving-room in which anterior-posterior oscillations of visual motion were presented using a sum-of-sines technique with five input frequencies (from 0.12 to 1.24Hz). Infants were tested in five conditions that varied in the amplitude of visual motion (from 0 to 8.64cm). Gain and phase responses of infants' postural sway were analyzed. Our results showed that infants, from a few months post-sitting to 1 year post-walking, were able to control their sitting posture in response to various frequency and amplitude properties of the visual motion. Infants showed an adult-like inverted-U pattern for the frequency response to visual inputs with the highest gain at 0.52 and 0.76Hz. As the visual motion amplitude increased, the gain response decreased. For the phase response, an adult-like frequency-dependent pattern was observed in all amplitude conditions for the experienced walkers. Newly sitting infants, however, showed variable postural behavior and did not systemically respond to the visual stimulus. Our results suggest that visual-postural entrainment and sensory re-weighting are fundamental processes that are present after a few months post sitting. Sensorimotor refinement during early postural development may result from the interactions of improved self-motion control and enhanced perceptual abilities. PMID:26979899

  1. Postural Rehabilitation for Adolescent Idiopathic Scoliosis during Growth.

    PubMed

    Weiss, Hans-Rudolf; Moramarco, Marc Michael; Borysov, Maksym; Ng, Shu Yan; Lee, Sang Gil; Nan, Xiaofeng; Moramarco, Kathryn Ann

    2016-06-01

    Long-term follow-up of untreated patients with adolescent idiopathic scoliosis (AIS) indicates that, with the exception of some extremely severe cases, AIS does not have a significant impact on quality of life and does not result in dire consequences. In view of the relatively benign nature of AIS and the long-term complications of surgery, the indications for treatment should be reviewed. Furthermore, recent studies have shown that scoliosis-specific exercises focusing on postural rehabilitation can positively influence the spinal curvatures in growing adolescents. Experiential postural re-education is a conservative, non-invasive approach, and its role in the management of AIS warrants further study. This article reviews current evidence for the inclusion of various forms of postural reeducation in the management of AIS. Recent comprehensive reviews have been researched including a manual and PubMed search for evidence regarding the effectiveness of physical/postural re-education/physiotherapy programs in growing AIS patients. This search revealed that there were few studies on the application of postural re-education in the management of AIS. These studies revealed that postural re-education in the form of exercise rehabilitation programs may have a positive influence on scoliosis; however, the various programs were difficult to compare. More research is necessary. There is at present Level 1 evidence for the effectiveness of Schroth scoliosis exercises in the management of AIS. Whether this evidence can be extrapolated to include other forms of scoliosis- pattern-specific exercises requires further investigation. Because corrective postures theoretically reduce the asymmetric loading of the spinal deformities and reverse the vicious cycle of spinal curvature progression, their integration into AIS programs may be beneficial and should be further examined. PMID:27340540

  2. Ankle and hip postural strategies defined by joint torques.

    PubMed

    Runge, C F; Shupert, C L; Horak, F B; Zajac, F E

    1999-10-01

    Previous studies have identified two discrete strategies for the control of posture in the sagittal plane based on EMG activations, body kinematics, and ground reaction forces. The ankle strategy was characterized by body sway resembling a single-segment-inverted pendulum and was elicited on flat support surfaces. In contrast, the hip strategy was characterized by body sway resembling a double-segment inverted pendulum divided at the hip and was elicited on short or compliant support surfaces. However, biomechanical optimization models have suggested that hip strategy should be observed in response to fast translations on a flat surface also, provided the feet are constrained to remain in contact with the floor and the knee is constrained to remain straight. The purpose of this study was to examine the experimental evidence for hip strategy in postural responses to backward translations of a flat support surface and to determine whether analyses of joint torques would provide evidence for two separate postural strategies. Normal subjects standing on a flat support surface were translated backward with a range of velocities from fast (55 cm/s) to slow (5 cm/s). EMG activations and joint kinematics showed pattern changes consistent with previous experimental descriptions of mixed hip and ankle strategy with increasing platform velocity. Joint torque analyses revealed the addition of a hip flexor torque to the ankle plantarflexor torque during fast translations. This finding indicates the addition of hip strategy to ankle strategy to produce a continuum of postural responses. Hip torque without accompanying ankle torque (pure hip strategy) was not observed. Although postural control strategies have previously been defined by how the body moves, we conclude that joint torques, which indicate how body movements are produced, are useful in defining postural control strategies. These results also illustrate how the biomechanics of the body can transform discrete control

  3. One month of contemporary dance modulates fractal posture in aging.

    PubMed

    Coubard, Olivier A; Ferrufino, Lena; Nonaka, Tetsushi; Zelada, Oscar; Bril, Blandine; Dietrich, Gilles

    2014-01-01

    Understanding the human aging of postural control and how physical or motor activity improves balance and gait is challenging for both clinicians and researchers. Previous studies have evidenced that physical and sporting activity focusing on cardiovascular and strength conditioning help older adults develop their balance and gait and/or decrease their frequency of falls. Motor activity based on motor-skill learning has also been put forward as an alternative to develop balance and/or prevent falls in aging. Specifically dance has been advocated as a promising program to boost motor control. In this study, we examined the effects of contemporary dance (CD) on postural control of older adults. Upright stance posturography was performed in 38 participants aged 54-89 years before and after the intervention period, during which one half of the randomly assigned participants was trained to CD and the other half was not trained at all (no dance, ND). CD training lasted 4 weeks, 3 times a week. We performed classical statistic scores of postural signal and dynamic analyses, namely signal diffusion analysis (SDA), recurrence quantification analysis (RQA), and detrended fluctuation analysis (DFA). CD modulated postural control in older trainees, as revealed in the eyes closed condition by a decrease in fractal dimension and an increase in DFA alpha component in the mediolateral plane. The ND group showed an increase in length and mean velocity of postural signal, and the eyes open a decrease in RQA maximal diagonal line in the anteroposterior plane and an increase in DFA alpha component in the mediolateral plane. No change was found in SDA in either group. We suggest that such a massed practice of CD reduced the quantity of exchange between the subject and the environment by increasing their postural confidence. Since CD has low-physical but high-motor impact, we conclude that it may be recommended as a useful program to rehabilitate posture in aging. PMID:24611047

  4. Does a crouched leg posture enhance running stability and robustness?

    PubMed

    Blum, Yvonne; Birn-Jeffery, Aleksandra; Daley, Monica A; Seyfarth, Andre

    2011-07-21

    Humans and birds both walk and run bipedally on compliant legs. However, differences in leg architecture may result in species-specific leg control strategies as indicated by the observed gait patterns. In this work, control strategies for stable running are derived based on a conceptual model and compared with experimental data on running humans and pheasants (Phasianus colchicus). From a model perspective, running with compliant legs can be represented by the planar spring mass model and stabilized by applying swing leg control. Here, linear adaptations of the three leg parameters, leg angle, leg length and leg stiffness during late swing phase are assumed. Experimentally observed kinematic control parameters (leg rotation and leg length change) of human and avian running are compared, and interpreted within the context of this model, with specific focus on stability and robustness characteristics. The results suggest differences in stability characteristics and applied control strategies of human and avian running, which may relate to differences in leg posture (straight leg posture in humans, and crouched leg posture in birds). It has been suggested that crouched leg postures may improve stability. However, as the system of control strategies is overdetermined, our model findings suggest that a crouched leg posture does not necessarily enhance running stability. The model also predicts different leg stiffness adaptation rates for human and avian running, and suggests that a crouched avian leg posture, which is capable of both leg shortening and lengthening, allows for stable running without adjusting leg stiffness. In contrast, in straight-legged human running, the preparation of the ground contact seems to be more critical, requiring leg stiffness adjustment to remain stable. Finally, analysis of a simple robustness measure, the normalized maximum drop, suggests that the crouched leg posture may provide greater robustness to changes in terrain height. PMID

  5. Ankle and hip postural strategies defined by joint torques

    NASA Technical Reports Server (NTRS)

    Runge, C. F.; Shupert, C. L.; Horak, F. B.; Zajac, F. E.; Peterson, B. W. (Principal Investigator)

    1999-01-01

    Previous studies have identified two discrete strategies for the control of posture in the sagittal plane based on EMG activations, body kinematics, and ground reaction forces. The ankle strategy was characterized by body sway resembling a single-segment-inverted pendulum and was elicited on flat support surfaces. In contrast, the hip strategy was characterized by body sway resembling a double-segment inverted pendulum divided at the hip and was elicited on short or compliant support surfaces. However, biomechanical optimization models have suggested that hip strategy should be observed in response to fast translations on a flat surface also, provided the feet are constrained to remain in contact with the floor and the knee is constrained to remain straight. The purpose of this study was to examine the experimental evidence for hip strategy in postural responses to backward translations of a flat support surface and to determine whether analyses of joint torques would provide evidence for two separate postural strategies. Normal subjects standing on a flat support surface were translated backward with a range of velocities from fast (55 cm/s) to slow (5 cm/s). EMG activations and joint kinematics showed pattern changes consistent with previous experimental descriptions of mixed hip and ankle strategy with increasing platform velocity. Joint torque analyses revealed the addition of a hip flexor torque to the ankle plantarflexor torque during fast translations. This finding indicates the addition of hip strategy to ankle strategy to produce a continuum of postural responses. Hip torque without accompanying ankle torque (pure hip strategy) was not observed. Although postural control strategies have previously been defined by how the body moves, we conclude that joint torques, which indicate how body movements are produced, are useful in defining postural control strategies. These results also illustrate how the biomechanics of the body can transform discrete control

  6. Aerial radiation survey at a military range.

    SciTech Connect

    Williams, G. P.; Martino, L. E.; Wrobel, J.; Environmental Assessment; U.S. Army Aberdeen Proving Ground

    2001-04-01

    Aberdeen Proving Ground (APG) is currently listed on the Superfund National Priorities List because of past waste handling practices at 13 'study areas.' Concern has been expressed that anthropogenic radioisotopes may have been released at some of the study areas, with the potential of posing health risks to human or ecological receptors. This concern was addressed by thoroughly searching archival records, sampling and analyzing environmental media, and performing an aerial radiation survey. The aerial radiation survey techniques employed have been used over all U.S. Department of Energy and commercial reactor sites. Use of the Aerial Measurement System (AMS) allowed investigators to safely survey areas where surveys using hand-held instruments would be difficult to perform. In addition, the AMS delivered a full spectrum of the measured gamma radiation, thereby providing a means of determining which radioisotopes were present at the surface. As a quality check on the aerial measurements, four ground truth measurements were made at selected locations and compared with the aerial data for the same locations. The results of the survey revealed no evidence of surface radioactive contamination. The measured background radiation, including the cosmic contribution, ranged from 4 to 11 {mu}R/h.

  7. Autoimmune Basis for Postural Tachycardia Syndrome

    PubMed Central

    Li, Hongliang; Yu, Xichun; Liles, Campbell; Khan, Muneer; Vanderlinde‐Wood, Megan; Galloway, Allison; Zillner, Caitlin; Benbrook, Alexandria; Reim, Sean; Collier, Daniel; Hill, Michael A.; Raj, Satish R.; Okamoto, Luis E.; Cunningham, Madeleine W.; Aston, Christopher E.; Kem, David C.

    2014-01-01

    Background Patients with postural tachycardia syndrome (POTS) have exaggerated orthostatic tachycardia often following a viral illness, suggesting autoimmunity may play a pathophysiological role in POTS. We tested the hypothesis that they harbor functional autoantibodies to adrenergic receptors (AR). Methods and Results Fourteen POTS patients (7 each from 2 institutions) and 10 healthy subjects were examined for α1AR autoantibody‐mediated contractility using a perfused rat cremaster arteriole assay. A receptor‐transfected cell‐based assay was used to detect the presence of β1AR and β2AR autoantibodies. Data were normalized and expressed as a percentage of baseline. The sera of all 14 POTS patients demonstrated significant arteriolar contractile activity (69±3% compared to 91±1% of baseline for healthy controls, P<0.001) when coexisting β2AR dilative activity was blocked; and this was suppressed by α1AR blockade with prazosin. POTS sera acted as a partial α1AR antagonist significantly shifting phenylephrine contractility curves to the right. All POTS sera increased β1AR activation (130±3% of baseline, P<0.01) and a subset had increased β2AR activity versus healthy subjects. POTS sera shifted isoproterenol cAMP response curves to the left, consistent with enhanced β1AR and β2AR agonist activity. Autoantibody‐positive POTS sera demonstrated specific binding to β1AR, β2AR, and α1AR in transfected cells. Conclusions POTS patients have elevated α1AR autoantibodies exerting a partial peripheral antagonist effect resulting in a compensatory sympathoneural activation of α1AR for vasoconstriction and concurrent βAR‐mediated tachycardia. Coexisting β1AR and β2AR agonistic autoantibodies facilitate this tachycardia. These findings may explain the increased standing plasma norepinephrine and excessive tachycardia observed in many POTS patients. PMID:24572257

  8. Postural tachycardia syndrome: time frequency mapping.

    PubMed

    Novak, V; Novak, P; Opfer-Gehrking, T L; Low, P A

    1996-12-14

    Orthostatic tachycardia is common but its specificity remains uncertain. Our preliminary work suggested that using autonomic function testing in conjunction with time-frequency mapping (TFM), it might be possible to characterize a subset of the postural tachycardia syndrome (POTS), that is due to a restricted autonomic neuropathy. We describe 20 patients (17 women and 3 men, aged 14-43 years) with florid POTS and 20 controls (14 women and 6 men, aged 20-41 years). Autonomic failure was quantified by its distribution (cardiovagal, adrenergic and sudomotor) and severity, a symptom profile was generated, and spectral indices, based on modified Wigner distribution during rest and head-up tilt (80 degrees) were evaluated. During tilt-up POTS patients differed from controls by an excessive heart rate (> 130 bpm) (P < 0.001), and higher diastolic pressure (P < 0.01). During rest, cardiovagal oscillations (at respiratory frequencies [RF]) and slow rhythms at nonrespiratory frequencies (NONRF) (from 0.01 to 0.07 Hz) in R-R intervals (RRI) (P < 0.01) were reduced. Both RF and NONRF rhythms in RRI were further blunted with tilt-up (P < 0.001). Slow adrenergic vasomotor rhythms in blood pressure (BP) (approximately 0.07 Hz) surged with tilt-up and returned to normal levels afterwards. The index of sympatho-vagal balance (NONRF-Systolic BP (SBP)/RF-RRI) was dramatically increased in POTS (P < 0.001). Distal postganglionic sudomotor failure was observed, and impairment of the BP responses to the Valsalva maneuver (phase II) suggested peripheral adrenergic dysfunction. Persistent orthostatic dizziness, tiredness, gastrointestinal symptoms and palpitations were common in POTS patients. It is possible to identify a subset of POTS patients who have a length-dependent autonomic neuropathy, affecting the peripheral adrenergic and cardiovagal fibers, with relative preservation of cardiac adrenergic fibers. PMID:8988490

  9. University Football Players, Postural Stability, and Concussions.

    PubMed

    Graves, Barbara Sue

    2016-02-01

    Concussion in football athletes is certainly more prevalent and has potentially serious outcomes. With current concerns and increasing return-to-play issues, additional assessment focus is needed. Division 1 college football athletes, from 18 to 20.9 years (n = 177; age, 19.7 ± 1.2 years; height, 182.3 ± 4.5 cm; weight, 97.3 ± 10.6 kg), before fall practice, over a period of 3 years, underwent baseline postural stability testing (sensory organization test [SOT], NeuroCom). Individuals, who were diagnosed with a concussion (headache, dizziness, fatigue, confusion, or loss of consciousness) during practice or actual competition (n = 15; age, 18.9 ± 0.9 years; height, 181.8 ± 2.5 cm; weight, 86.6 ± 3.6 kg), underwent serial evaluation after injury and 24 hours after concussion. As soon as the player was considered asymptomatic, the test was completed on the first and 14th day. A control group of noninjured male athletes (n = 15; age, 19.1 ± 0.4 years; height, 178.2 ± 3.2 cm; weight, 78.6 ± 2.1 kg) were tested for the same time frame. This particular study was only one part of the total evaluation conducted for the concussed athlete's return to play. Results indicated that the concussion group had a statistically significant (p = 0.037) change from their baseline SOT score and the control group (p = 0.025). This change remained significant until day 14 of posttesting. These data indicate that the SOT, when available, may be a positive additional assessment of concussed college-aged football players. Professionals, when dealing with concussion in competitive sports, do need to continue to work together, but awareness of SOT assessments may also contribute to the return-to-play decisions. PMID:26284680

  10. Postural tachycardia syndrome: time frequency mapping

    NASA Technical Reports Server (NTRS)

    Novak, V.; Novak, P.; Opfer-Gehrking, T. L.; Low, P. A.

    1996-01-01

    Orthostatic tachycardia is common but its specificity remains uncertain. Our preliminary work suggested that using autonomic function testing in conjunction with time-frequency mapping (TFM), it might be possible to characterize a subset of the postural tachycardia syndrome (POTS), that is due to a restricted autonomic neuropathy. We describe 20 patients (17 women and 3 men, aged 14-43 years) with florid POTS and 20 controls (14 women and 6 men, aged 20-41 years). Autonomic failure was quantified by its distribution (cardiovagal, adrenergic and sudomotor) and severity, a symptom profile was generated, and spectral indices, based on modified Wigner distribution during rest and head-up tilt (80 degrees) were evaluated. During tilt-up POTS patients differed from controls by an excessive heart rate (> 130 bpm) (P < 0.001), and higher diastolic pressure (P < 0.01). During rest, cardiovagal oscillations (at respiratory frequencies [RF]) and slow rhythms at nonrespiratory frequencies (NONRF) (from 0.01 to 0.07 Hz) in R-R intervals (RRI) (P < 0.01) were reduced. Both RF and NONRF rhythms in RRI were further blunted with tilt-up (P < 0.001). Slow adrenergic vasomotor rhythms in blood pressure (BP) (approximately 0.07 Hz) surged with tilt-up and returned to normal levels afterwards. The index of sympatho-vagal balance (NONRF-Systolic BP (SBP)/RF-RRI) was dramatically increased in POTS (P < 0.001). Distal postganglionic sudomotor failure was observed, and impairment of the BP responses to the Valsalva maneuver (phase II) suggested peripheral adrenergic dysfunction. Persistent orthostatic dizziness, tiredness, gastrointestinal symptoms and palpitations were common in POTS patients. It is possible to identify a subset of POTS patients who have a length-dependent autonomic neuropathy, affecting the peripheral adrenergic and cardiovagal fibers, with relative preservation of cardiac adrenergic fibers.

  11. Dynamic posture analysis of Spacelab-1 crew members

    NASA Technical Reports Server (NTRS)

    Anderson, D. J.; Reschke, M. F.; Homick, J. E.; Werness, S. A.

    1986-01-01

    Dynamic posture testing was conducted on the science crew of the Spacelab-1 mission on a single axis linear motion platform. Tests took place in pre- and post-flight sessions lasting approximately 20 min each. The pre-flight tests were widely spaced over the several months prior to the mission while the post-flight tests were conducted over the first, second, fourth, and sixth days after landing. Two of the crew members were also tested on the day of landing. Consistent with previous postural testing conducted on flight crews, these crew members were able to complete simple postural tasks to an acceptable level even in the first few hours after landing. Our tests were designed to induce dynamic postural responses using a variety of stimuli and from these responses, evaluate subtle changes in the postural control system which had occurred over the duration of the flight. Periodic sampling post-flight allowed us to observe the time course of readaptation to terrestrial life. Our observations of hip and shoulder position, when subjected to careful analysis, indicated modification of the postural response from pre- to post-flight and that demonstrable adjustments in the dynamic control of their postural systems were taking place in the first few days after flight. For transient stimuli where the platform on which they were asked to stand quickly moved a few centimeters fore or aft then stopped, ballistic or open loop 'programs' would closely characterize the response. During these responses the desired target position was not always achieved and of equal importance not always properly corrected some 15 seconds after the platform ceased to move. The persistent observation was that the subjects had a much stronger dependence on visual stabilization post-flight than pre-flight. This was best illustrated by a slow or only partial recovery to an upward posture after a transient base-of-support movement with eyes open. Postural responses to persistent wideband pseudorandom

  12. Corticospinal Excitability of Trunk Muscles during Different Postural Tasks

    PubMed Central

    Chiou, Shin-Yi; Gottardi, Sam E. A.; Hodges, Paul W.; Strutton, Paul H.

    2016-01-01

    Evidence suggests that the primary motor cortex (M1) is involved in both voluntary, goal-directed movements and in postural control. Trunk muscles are involved in both tasks, however, the extent to which M1 controls these muscles in trunk flexion/extension (voluntary movement) and in rapid shoulder flexion (postural control) remains unclear. The purpose of this study was to investigate this question by examining excitability of corticospinal inputs to trunk muscles during voluntary and postural tasks. Twenty healthy adults participated. Transcranial magnetic stimulation was delivered to the M1 to examine motor evoked potentials (MEPs) in the trunk muscles (erector spinae (ES) and rectus abdominis (RA)) during dynamic shoulder flexion (DSF), static shoulder flexion (SSF), and static trunk extension (STE). The level of background muscle activity in the ES muscles was matched across tasks. MEP amplitudes in ES were significantly larger in DSF than in SSF or in STE; however, this was not observed for RA. Further, there were no differences in levels of muscle activity in RA between tasks. Our findings reveal that corticospinal excitability of the ES muscles appears greater during dynamic anticipatory posture-related adjustments than during static tasks requiring postural (SSF) and goal-directed voluntary (STE) activity. These results suggest that task-oriented rehabilitation of trunk muscles should be considered for optimal transfer of therapeutic effect to function. PMID:26807583

  13. Postural responses during the various frequencies of anteroposterior perturbation.

    PubMed

    Han, Kap Soo; Shin, Sun Hye; Yu, Chang Ho; Kwon, Tae Kyu

    2014-01-01

    This study investigated the characteristics of dynamic postural responses when subjects attempted to maintain an upright standing position on a support plate during continuous sinusoidal perturbation in the anterior-posterior direction. Fifteen healthy young subjects participated in the experiment. Body movement patterns during the perturbation were captured and analyzed using a 3D motion analysis system (APAS 3D motion analysis, Ariel Dynamics Inc.). Seven markers were attached on the subject's body to measure and analyze the motion patterns. The markers were positioned at the head, chest, hip, right knee, left knee, right ankle, and left ankle. Five different frequencies of motion were applied to the support surface: 0.1, 0.5, 1.0, 1.5, and 2.0 Hz with a 4-cm path of motion at the base. The experiments measured dynamic postural responses in a condition were subjects had their eyes open. The results showed that the median frequency of the knee and ankle increased in all frequency bands. Following an increase in the frequency of the perturbation, the postural control strategy was changed from the ankle strategy to a combined strategy. These experimental results could be applied to the dynamic postural training for the elderly and to rehabilitation training for patients to improve their ability for postural control. PMID:25226955

  14. Nonplantigrade Foot Posture: A Constraint on Dinosaur Body Size

    PubMed Central

    Kubo, Tai; Kubo, Mugino O.

    2016-01-01

    Dinosaurs had functionally digitigrade or sub-unguligrade foot postures. With their immediate ancestors, dinosaurs were the only terrestrial nonplantigrades during the Mesozoic. Extant terrestrial mammals have different optimal body sizes according to their foot posture (plantigrade, digitigrade, and unguligrade), yet the relationship of nonplantigrade foot posture with dinosaur body size has never been investigated, even though the body size of dinosaurs has been studied intensively. According to a large dataset presented in this study, the body sizes of all nonplantigrades (including nonvolant dinosaurs, nonvolant terrestrial birds, extant mammals, and extinct Nearctic mammals) are above 500 g, except for macroscelid mammals (i.e., elephant shrew), a few alvarezsauroid dinosaurs, and nondinosaur ornithodirans (i.e., the immediate ancestors of dinosaurs). When nonplantigrade tetrapods evolved from plantigrade ancestors, lineages with nonplantigrade foot posture exhibited a steady increase in body size following Cope’s rule. In contrast, contemporaneous plantigrade lineages exhibited no trend in body size evolution and were largely constrained to small body sizes. This evolutionary pattern of body size specific to foot posture occurred repeatedly during both the Mesozoic and the Cenozoic eras. Although disturbed by the end-Cretaceous extinction, species of mid to large body size have predominantly been nonplantigrade animals from the Jurassic until the present; conversely, species with small body size have been exclusively composed of plantigrades in the nonvolant terrestrial tetrapod fauna. PMID:26790003

  15. Effects of emotional videos on postural control in children.

    PubMed

    Brandão, Arthur de Freitas; Palluel, Estelle; Olivier, Isabelle; Nougier, Vincent

    2016-03-01

    The link between emotions and postural control has been rather unexplored in children. The objective of the present study was to establish whether the projection of pleasant and unpleasant videos with similar arousal would lead to specific postural responses such as postural freezing, aversive or appetitive behaviours as a function of age. We hypothesized that postural sway would similarly increase with the viewing of high arousal videos in children and adults, whatever the emotional context. 40 children participated in the study and were divided into two groups of age: group 7-9 years (n=23; mean age=8 years ± 0.7) and group 10-12 years (n=17; mean age=11 years ± 0.7). 19 adults (mean age=25.8 years ± 4.4) also took part in the experiment. They viewed emotional videos while standing still on a force platform. Centre of foot pressure (CoP) displacements were analysed. Antero-posterior, medio-lateral mean speed and sway path length increased similarly with the viewing of high arousal movies in the younger, older children, and adults. Our findings suggest that the development of postural control is not influenced by the maturation of the emotional processing. PMID:26979902

  16. Spatiotemporal interactions between audition and touch depend on hand posture.

    PubMed

    Sanabria, Daniel; Soto-Faraco, Salvador; Spence, Charles

    2005-09-01

    We report two experiments designed to assess the consequences of posture change on audiotactile spatiotemporal interactions. In Experiment 1, participants had to discriminate the direction of an auditory stream (consisting of the sequential presentation of two tones from different spatial positions) while attempting to ignore a task-irrelevant tactile stream (consisting of the sequential presentation of two vibrations, one to each of the participant's hands). The tactile stream presented to the participants' hands was either spatiotemporally congruent or incongruent with respect to the sounds. A significant decrease in performance in incongruent trials compared with congruent trials was demonstrated when the participants adopted an uncrossed-hands posture but not when their hands were crossed over the midline. In Experiment 2, we investigated the ability of participants to discriminate the direction of two sequentially presented tactile stimuli (one presented to each hand) as a function of the presence of congruent vs incongruent auditory distractors. Here, the crossmodal effect was stronger in the crossed-hands posture than in the uncrossed-hands posture. These results demonstrate the reciprocal nature of audiotactile interactions in spatiotemporal processing, and highlight the important role played by body posture in modulating such crossmodal interactions. PMID:15942735

  17. Effect of Cognitive Load on Seating Posture in Children.

    PubMed

    Igarashi, Go; Karashima, Chieko; Hoshiyama, Minoru

    2016-03-01

    Although children are frequently required to sit upright, it is often difficult to maintain this posture when performing cognitive tasks. Information about the relationship between a cognitive tasks and postural seating control is important for children to complete tasks more effectively. To determine the muscle activity and body sway of children in a seated posture while performing a cognitive task, changes in muscle activity and center of pressure (COP) were recorded while 4(th) grade children performed arithmetic tasks. Electromyography was recorded from the internal oblique and lumbar multifidus muscles, and the COP was recorded using a baropodometer placed on the stool. These variables were measured during easy (EA) and difficult (DA) arithmetic tasks. EMG activity decreased during the EA and DA tasks, while the COP was displaced in the DA task. The results of the arithmetic tasks were not related to the EMG or COP changes. Attention to maintain a seated posture may be reduced when children perform cognitive tasks. Therefore, it may be better to allow children to alter their posture especially when they are performing difficult tasks. In this research, we only used arithmetic tasks as the cognitive exercise, and therefore, other types of tasks should be examined. PMID:26317316

  18. Development and initial validation of the Seated Posture Scale.

    PubMed

    Barks, Lelia; Luther, Stephen L; Brown, Lisa M; Schulz, Brian; Bowen, Mary Elizabeth; Powell-Cope, Gail

    2015-01-01

    Literature shows that some health outcomes (e.g., eating, breathing, and speaking) are directly related to posture. Evidence of outcomes mediated by wheelchair seated posture is limited to interface pressure, physical function, and wheelchair skills and safety. This study's purpose was to develop and validate a rapid, low-burden, paper-pencil assessment of wheelchair seated posture for research use and to test feasibility of its use with a sample of older adults. We used a prospective design and a convenience sample of older adults who were receiving rehabilitation services in a community living center. Forty-nine older wheelchair users participated. Main measures were the Seated Posture Scale (SPS), Modified Ashworth Scale, Barthel Index, Visual Descriptor Scale, scale-content validity index (S-CVI), Cronbach alpha, and test-retest reliability. Rating by six experts yielded the overall content validity score (S-CVI) of 0.744. Total SPS score correlated positively with physical function (Barthel Index, r = 0.46, p < 0.001) and negatively with muscle tone (Modified Ashworth Scale, r = -0.44, p = 0.001), supporting SPS construct validity. Internal consistency was 0.66 (Cronbach alpha). Test-retest reliability yielded Pearson product-moment correlations of 0.89 to 0.99. We conclude that the SPS has sufficient preliminary validity and reliability to support its use as an evaluation of wheelchair seated posture in outcomes research. PMID:26230339

  19. Working posture and its predictors in hospital operating room nurses

    PubMed Central

    Abdollahzade, Farahnaz; Mohammadi, Fariba; Dianat, Iman; Asghari, Elnaz; Asghari-Jafarabadi, Mohammad; Sokhanvar, Zahra

    2016-01-01

    Background: This study was conducted to evaluate working posture of operating room nurses and its relationship with demographic and job details of this group. Methods: This cross-sectional study was conducted among 147 operating room nurses in Tabriz, Iran using a questionnaire and the Rapid Entire Body Assessment (REBA) checklist. The data were analyzed with SPSS.16 using t test, Pearson correlation coefficient and analysis of variance (ANOVA) tests for univariate analysis and the linear regression test for multivariate analysis. Results: The mean (SD) of REBA score was 7.7 (1.9), which means a high risk level and highlights an urgent need to change the working postures of the studied nurses. There was significant relationship between working posture and age (P = 0.003), gender (P = 0.003), regular daily exercise (P = 0.048), work experience (P = 0.003), number of shifts per month (P = 0.006) and type of operating rooms (P < 0.001) in univariate analyses. Gender and type of operating room were the predictors of working posture of nurses in multivariate analysis. Conclusion: The findings highlight the need for ergonomic interventions and educational programs to improve working posture of this study population, which can consequently lead to promotion of health and well-being of this group. PMID:27123432

  20. Stance Postural Strategies in Patients with Chronic Inflammatory Demyelinating Polyradiculoneuropathy

    PubMed Central

    Missori, Paolo; Trompetto, Carlo; Fattapposta, Francesco

    2016-01-01

    Introduction Polyneuropathy leads to postural instability and an increased risk of falling. We investigated how impaired motor impairment and proprioceptive input due to neuropathy influences postural strategies. Methods Platformless bisegmental posturography data were recorded in healthy subjects and patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Each subject stood on the floor, wore a head and a hip electromagnetic tracker. Sway amplitude and velocity were recorded and the mean direction difference (MDD) in the velocity vector between trackers was calculated as a flexibility index. Results Head and hip postural sway increased more in patients with CIDP than in healthy controls. MDD values reflecting hip strategies also increased more in patients than in controls. In the eyes closed condition MDD values in healthy subjects decreased but in patients remained unchanged. Discussion Sensori-motor impairment changes the balance between postural strategies that patients adopt to maintain upright quiet stance. Motor impairment leads to hip postural strategy overweight (eyes open), and prevents strategy re-balancing when the sensory context predominantly relies on proprioceptive input (eyes closed). PMID:26977594

  1. Influence of gymnastics training on the development of postural control.

    PubMed

    Garcia, Claudia; Barela, José Angelo; Viana, André Rocha; Barela, Ana Maria Forti

    2011-03-29

    This study investigated the influence of gymnastics training on the postural control of children with and without the use of visual information. Two age groups, aged 5-7 and 9-11 years old, of gymnasts and nongymnasts were asked to maintain an upright and quiet stance on a force platform with eyes open (EO) and eyes closed (EC) for 30s. Area of the stabilogram (AOS) and mean velocity of the center of pressure (COP) in anterior-posterior (AP) and medial-lateral (ML) directions were calculated and used to investigate the effects of gymnastics training, age, and visual information. Younger gymnasts presented greater postural control compared to younger nongymnasts while visual information did not improve postural control in younger nongymnasts. Younger gymnasts displayed improved postural control with EO compared to EC. The mean velocity of the COP in the ML direction was: less for younger gymnasts than younger nongymnasts with EO. These results suggest that gymnastics training promotes improvements in postural control of younger children only, which results from their use of visual information when available. PMID:21276829

  2. Nonplantigrade Foot Posture: A Constraint on Dinosaur Body Size.

    PubMed

    Kubo, Tai; Kubo, Mugino O

    2016-01-01

    Dinosaurs had functionally digitigrade or sub-unguligrade foot postures. With their immediate ancestors, dinosaurs were the only terrestrial nonplantigrades during the Mesozoic. Extant terrestrial mammals have different optimal body sizes according to their foot posture (plantigrade, digitigrade, and unguligrade), yet the relationship of nonplantigrade foot posture with dinosaur body size has never been investigated, even though the body size of dinosaurs has been studied intensively. According to a large dataset presented in this study, the body sizes of all nonplantigrades (including nonvolant dinosaurs, nonvolant terrestrial birds, extant mammals, and extinct Nearctic mammals) are above 500 g, except for macroscelid mammals (i.e., elephant shrew), a few alvarezsauroid dinosaurs, and nondinosaur ornithodirans (i.e., the immediate ancestors of dinosaurs). When nonplantigrade tetrapods evolved from plantigrade ancestors, lineages with nonplantigrade foot posture exhibited a steady increase in body size following Cope's rule. In contrast, contemporaneous plantigrade lineages exhibited no trend in body size evolution and were largely constrained to small body sizes. This evolutionary pattern of body size specific to foot posture occurred repeatedly during both the Mesozoic and the Cenozoic eras. Although disturbed by the end-Cretaceous extinction, species of mid to large body size have predominantly been nonplantigrade animals from the Jurassic until the present; conversely, species with small body size have been exclusively composed of plantigrades in the nonvolant terrestrial tetrapod fauna. PMID:26790003

  3. The Development and Flight Testing of an Aerially Deployed Unmanned Aerial System

    NASA Astrophysics Data System (ADS)

    Smith, Andrew

    An investigation into the feasibility of aerial deployed unmanned aerial vehicles was completed. The investigation included the development and flight testing of multiple unmanned aerial systems to investigate the different components of potential aerial deployment missions. The project consisted of two main objectives; the first objective dealt with the development of an airframe capable of surviving aerial deployment from a rocket and then self assembling from its stowed configuration into its flight configuration. The second objective focused on the development of an autopilot capable of performing basic guidance, navigation, and control following aerial deployment. To accomplish these two objectives multiple airframes were developed to verify their completion experimentally. The first portion of the project, investigating the feasibility of surviving an aerial deployment, was completed using a fixed wing glider that following a successful deployment had 52 seconds of controlled flight. Before developing the autopilot in the second phase of the project, the glider was significantly upgraded to fix faults discovered in the glider flight testing and to enhance the system capabilities. Unfortunately to conform to outdoor flight restrictions imposed by the university and the Federal Aviation Administration it was required to switch airframes before flight testing of the new fixed wing platform could begin. As a result, an autopilot was developed for a quadrotor and verified experimentally completely indoors to remain within the limits of governing policies.

  4. Evaluation of unmanned aerial vehicle shape, flight path and camera type for waterfowl surveys: disturbance effects and species recognition.

    PubMed

    McEvoy, John F; Hall, Graham P; McDonald, Paul G

    2016-01-01

    The use of unmanned aerial vehicles (UAVs) for ecological research has grown rapidly in recent years, but few studies have assessed the disturbance impacts of these tools on focal subjects, particularly when observing easily disturbed species such as waterfowl. In this study we assessed the level of disturbance that a range of UAV shapes and sizes had on free-living, non-breeding waterfowl surveyed in two sites in eastern Australia between March and May 2015, as well as the capability of airborne digital imaging systems to provide adequate resolution for unambiguous species identification of these taxa. We found little or no obvious disturbance effects on wild, mixed-species flocks of waterfowl when UAVs were flown at least 60m above the water level (fixed wing models) or 40m above individuals (multirotor models). Disturbance in the form of swimming away from the UAV through to leaving the water surface and flying away from the UAV was visible at lower altitudes and when fixed-wing UAVs either approached subjects directly or rapidly changed altitude and/or direction near animals. Using tangential approach flight paths that did not cause disturbance, commercially available onboard optical equipment was able to capture images of sufficient quality to identify waterfowl and even much smaller taxa such as swallows. Our results show that with proper planning of take-off and landing sites, flight paths and careful UAV model selection, UAVs can provide an excellent tool for accurately surveying wild waterfowl populations and provide archival data with fewer logistical issues than traditional methods such as manned aerial surveys. PMID:27020132

  5. Evaluation of unmanned aerial vehicle shape, flight path and camera type for waterfowl surveys: disturbance effects and species recognition

    PubMed Central

    Hall, Graham P.; McDonald, Paul G.

    2016-01-01

    The use of unmanned aerial vehicles (UAVs) for ecological research has grown rapidly in recent years, but few studies have assessed the disturbance impacts of these tools on focal subjects, particularly when observing easily disturbed species such as waterfowl. In this study we assessed the level of disturbance that a range of UAV shapes and sizes had on free-living, non-breeding waterfowl surveyed in two sites in eastern Australia between March and May 2015, as well as the capability of airborne digital imaging systems to provide adequate resolution for unambiguous species identification of these taxa. We found little or no obvious disturbance effects on wild, mixed-species flocks of waterfowl when UAVs were flown at least 60m above the water level (fixed wing models) or 40m above individuals (multirotor models). Disturbance in the form of swimming away from the UAV through to leaving the water surface and flying away from the UAV was visible at lower altitudes and when fixed-wing UAVs either approached subjects directly or rapidly changed altitude and/or direction near animals. Using tangential approach flight paths that did not cause disturbance, commercially available onboard optical equipment was able to capture images of sufficient quality to identify waterfowl and even much smaller taxa such as swallows. Our results show that with proper planning of take-off and landing sites, flight paths and careful UAV model selection, UAVs can provide an excellent tool for accurately surveying wild waterfowl populations and provide archival data with fewer logistical issues than traditional methods such as manned aerial surveys. PMID:27020132

  6. Ground cover estimated from aerial photographs

    NASA Technical Reports Server (NTRS)

    Gerbermann, A. H.; Cuellar, J. A.; Wiegand, C. L.

    1976-01-01

    Estimates of per cent ground cover made by ground observers were compared with independent estimates made on the basis of low-altitude (640-1219 m) aerial photographs of the same fields. Standard statistical simple correlation and linear regression analyses revealed a high correlation between the two estimation methods. In crops such as grain, sorghum, corn, and forage sorghum, in which the broadest part of the leaf canopy is near the top of the plant, there was a tendency to overestimate the per cent ground cover from aerial photographs.

  7. Noise from aerial bursts of fireworks

    NASA Technical Reports Server (NTRS)

    Maglieri, D. J.; Henderson, H. R.

    1973-01-01

    A study was made recording the pressure time histories of the aerial bursts of mortars of various sizes launched during an actual fireworks display. The peak overpressure and duration of blast noise as well as the energy spectral density are compared with the characteristics of a blasting cap and of an F-104 aircraft at a Mach number of 1.4 and an altitude of 42,000 ft. Noise levels of the fireworks aerial bursts peaked 15 decibels below levels deemed damaging to hearing.

  8. Advanced Image Processing of Aerial Imagery

    NASA Technical Reports Server (NTRS)

    Woodell, Glenn; Jobson, Daniel J.; Rahman, Zia-ur; Hines, Glenn

    2006-01-01

    Aerial imagery of the Earth is an invaluable tool for the assessment of ground features, especially during times of disaster. Researchers at the NASA Langley Research Center have developed techniques which have proven to be useful for such imagery. Aerial imagery from various sources, including Langley's Boeing 757 Aries aircraft, has been studied extensively. This paper discusses these studies and demonstrates that better-than-observer imagery can be obtained even when visibility is severely compromised. A real-time, multi-spectral experimental system will be described and numerous examples will be shown.

  9. MicroProbe Small Unmanned Aerial System

    NASA Technical Reports Server (NTRS)

    Bland, Geoffrey; Miles, Ted

    2012-01-01

    The MicroProbe unmanned aerial system (UAS) concept incorporates twin electric motors mounted on the vehicle wing, thus enabling an aerodynamically and environmentally clean nose area for atmospheric sensors. A payload bay is also incorporated in the fuselage to accommodate remote sensing instruments. A key feature of this concept is lightweight construction combined with low flying speeds to minimize kinetic energy and associated hazards, as well as maximizing spatial resolution. This type of aerial platform is needed for Earth science research and environmental monitoring. There were no vehicles of this type known to exist previously.

  10. Metrically preserving the USGS aerial film archive

    USGS Publications Warehouse

    Moe, Donald; Longhenry, Ryan

    2013-01-01

    Since 1972, the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center in Sioux Falls, South Dakota, has provided fi lm-based products to the public. EROS is home to an archive of 12 million frames of analog photography ranging from 1937 to the present. The archive contains collections from both aerial and satellite platforms including programs such as the National High Altitude Program (NHAP), National Aerial Photography Program (NAPP), U.S. Antarctic Resource Center (USARC), Declass 1(CORONA, ARGON, and LANYARD), Declass 2 (KH-7 and KH-9), and Landsat (1972 – 1992, Landsat 1–5).

  11. Laser Doppler velocimeter aerial spray measurements

    NASA Technical Reports Server (NTRS)

    Zalay, A. D.; Eberle, W. R.; Howle, R. E.; Shrider, K. R.

    1978-01-01

    An experimental research program for measuring the location, spatial extent, and relative concentration of airborne spray clouds generated by agricultural aircraft is described. The measurements were conducted with a ground-based laser Doppler velocimeter. The remote sensing instrumentation, experimental tests, and the results of the flight tests are discussed. The cross section of the aerial spray cloud and the observed location, extent, and relative concentration of the airborne particulates are presented. It is feasible to use a mobile laser Doppler velocimeter to track and monitor the transport and dispersion of aerial spray generated by an agricultural aircraft.

  12. AERIAL OF VISITORS INFORMATION CENTER [VIC] & ROCKET GARDEN

    NASA Technical Reports Server (NTRS)

    1973-01-01

    AERIAL OF VISITORS INFORMATION CENTER [VIC] & ROCKET GARDEN KSC-373C-0556.20 116-KSC-373C-556.20, P-01622-B, ARCHIVE-04455 Aerial view of Easter crowds at Visitors Information Center, Kennedy Space Center, Florida.

  13. Lower lumbar spine axial rotation is reduced in end-range sagittal postures when compared to a neutral spine posture.

    PubMed

    Burnett, Angus; O'Sullivan, Peter; Ankarberg, Lars; Gooding, Megan; Nelis, Rogier; Offermann, Frank; Persson, Jannike

    2008-08-01

    Sports such as rowing, gymnastics, cycling and fast bowling in cricket that combine rotation with spine flexion and extension are known to carry greater risk of low back pain (LBP). Few studies have investigated the capacity of the lumbar spine to rotate in various sagittal positions, and further, these studies have generated disparate conclusions. The purpose of this study was to determine whether the range of lower lumbar axial rotation (L3-S2) is decreased in end-range flexion and extension postures when compared to the neutral spine posture. Eighteen adolescent female rowers (mean age=14.9 years) with no history of LBP were recruited for this study. Lower lumbar axial rotation was measured by an electromagnetic tracking system (3-Space Fastrak) in end-range flexion, extension and neutral postures, in sitting and standing positions. There was a reduction in the range of lower lumbar axial rotation in both end-range extension and flexion (p<0.001) postures when compared to neutral. Further, the range of lower lumbar axial rotation measurements in flexion when sitting was reduced when compared to standing (p=0.013). These findings are likely due to the anatomical limitations of the passive structures in end-range sagittal postures. PMID:17395521

  14. Effect of craniocervical posture on abdominal muscle activities

    PubMed Central

    Su, Jung Gil; Won, Shin Ji; Gak, Hwangbo

    2016-01-01

    [Purpose] The aim of this study was to investigate the influence of the craniocervical posture on abdominal muscle activities in hook-lying position. [Subjects] This study recruited 12 healthy young adults. [Methods] Each subject was asked to adopt a supine position with the hip and knee flexed at 60°. Surface electromyographic signals of transversus abdominis/internal oblique, rectus abdominis, and external oblique in different craniocervical postures (extension, neutral, and flexion) were compared. [Results] The transversus abdominis and rectus abdominis showed increased muscle activities in craniocervical flexion compared to craniocervical extension and neutral position. Greater muscle activities of the external oblique were seen in craniocervical flexion than in craniocervical extension. [Conclusion] Craniocervical flexion was found to be effective to increase the abdominal muscle activities. Consideration of craniocervical posture is recommended when performing trunk stabilization exercises. PMID:27065558

  15. Posture metrology for aerospace camera in the assembly of spacecraft

    NASA Astrophysics Data System (ADS)

    Yang, ZaiHua; Yang, Song; Wan, Bile; Pan, Tingyao; Long, Changyu

    2016-01-01

    During the spacecraft assembly process, the posture of the aerospace camera to the spacecraft coordinate system needs to be measured precisely, because the posture data are very important for the earth observing. In order to measure the angles between the camera optical axis and the spacecraft coordinate system's three axes x, y, z, a measurement scheme was designed. The scheme was based on the principle of space intersection measurement with theodolites. Three thodolites were used to respectively collimate the camera axis and two faces of a base cube. Then, through aiming at each other, a measurement network was built. Finally, the posture of the camera was measured. The error analysis and measurement experiments showed that the precision can reach 6″. This method has been used in the assembly of satellite GF-2 with satisfactory results.

  16. Dimension and Complexity in Human Movement and Posture.

    PubMed

    Morrison, Steven; Newell, Karl M

    2015-10-01

    There has been considerable effort over the last 25 years to understand the emergence of complexity in motor output and how this relates to properties of the individual (e.g., age, disease state, etc.), environment (e.g., information) and task (e.g., movement, posture, isometric force). This paper addresses the behavioral dimension of motor complexity in movement and posture from a degrees of freedom (DF) perspective together with the change of complexity through aging, disease and fatigue. The dimension of behavior for a given perceptual-motor output is shown to be relatively low, dependent on the interaction between the individual, environmental, and task constraints and varies within a limited adaptive range for a given motor task. The determination of dimension in movement and posture has taken us beyond the traditional motor performance scores of behavior but it is not a sufficient characterization of the adaptive and emergent processes of complexity. PMID:26375933

  17. Interindividual variation in posture allocation: possible role in human obesity.

    PubMed

    Levine, James A; Lanningham-Foster, Lorraine M; McCrady, Shelly K; Krizan, Alisa C; Olson, Leslie R; Kane, Paul H; Jensen, Michael D; Clark, Matthew M

    2005-01-28

    Obesity occurs when energy intake exceeds energy expenditure. Humans expend energy through purposeful exercise and through changes in posture and movement that are associated with the routines of daily life [called nonexercise activity thermogenesis (NEAT)]. To examine NEAT's role in obesity, we recruited 10 lean and 10 mildly obese sedentary volunteers and measured their body postures and movements every half-second for 10 days. Obese individuals were seated, on average, 2 hours longer per day than lean individuals. Posture allocation did not change when the obese individuals lost weight or when lean individuals gained weight, suggesting that it is biologically determined. If obese individuals adopted the NEAT-enhanced behaviors of their lean counterparts, they might expend an additional 350 calories (kcal) per day. PMID:15681386

  18. Kinect-based posture tracking for correcting positions during exercise.

    PubMed

    Guerrero, Cesar; Uribe-Quevedo, Alvaro

    2013-01-01

    The Kinect sensor has opened the path for developing numerous applications in several different areas. Medical and health applications are benefiting from the Kinect as it allows non-invasive body motion capture that can be used in motor rehabilitation and phobia treatment. A major advantage of the Kinect is that allows developing solutions that can be used at home or even the office thus, expanding the user freedom for interacting with complementary solutions to its physical activities without requiring any traveling. This paper present a Kinect-based posture tracking software for assisting the user in successfully match postures required in some exercises for strengthen body muscles. Unlike several video games available, this tool offers a user interface for customizing posture parameters, so it can be enhanced by healthcare professionals or by their guidance through the user. PMID:23400149

  19. Postural balance and the risk of falling during pregnancy.

    PubMed

    Cakmak, Bulent; Ribeiro, Ana Paula; Inanir, Ahmet

    2016-01-01

    Pregnancy is a physiological process and many changes occur in a woman's body during pregnancy. These changes occur in all systems to varying degrees, including the cardiovascular, respiratory, genitourinary, and musculoskeletal systems. The hormonal, anatomical, and physiological changes occurring during pregnancy result in weight gain, decreased abdominal muscle strength and neuromuscular control, increased ligamentous laxity, and spinal lordosis. These alterations shift the centre of gravity of the body, altering the postural balance and increasing the risk of falls. Falls during pregnancy can cause maternal and foetal complications, such as maternal bone fractures, head injuries, internal haemorrhage, abruption placenta, rupture of the uterus and membranes, and occasionally maternal death or intrauterine foetal demise. Preventative strategies, such as physical exercise and the use of maternity support belts, can increase postural stability and reduce the risk of falls during pregnancy. This article reviews studies that have investigated changes in postural balance and risk of falling during pregnancy. PMID:26212584

  20. Body posture evaluations in subjects with internal temporomandibular joint derangement.

    PubMed

    Munhoz, Wagner Cesar; Marques, Amélia Pasqual

    2009-10-01

    The aim of this study was to verify possible relationships between global body posture and temporomandibular joint internal derangement (TMJ-id), by comparing 30 subjects presenting typical TMJ-id signs to 20 healthy subjects. Body posture was assessed using the analysis of muscle chains on several photographs. Results show a higher frequency of lifted shoulders (p=0.04) and of changes in the antero-internal hip chain (p=0.02) in the test group, but no further differences were found significant between the control and test groups. The test group was then divided into three subgroups according to the Helkimo index of temporomandibular disorder severity. Again, no significant differences were found between the subgroups. However, there was a trend noticed in the group with the most severe dysfunction, to present a forward head and shoulders posture. Results are discussed in light of previous studies using the same sample. PMID:19891257

  1. Classification of posture maintenance data with fuzzy clustering algorithms

    NASA Technical Reports Server (NTRS)

    Bezdek, James C.

    1992-01-01

    Sensory inputs from the visual, vestibular, and proprioreceptive systems are integrated by the central nervous system to maintain postural equilibrium. Sustained exposure to microgravity causes neurosensory adaptation during spaceflight, which results in decreased postural stability until readaptation occurs upon return to the terrestrial environment. Data which simulate sensory inputs under various sensory organization test (SOT) conditions were collected in conjunction with Johnson Space Center postural control studies using a tilt-translation device (TTD). The University of West Florida applied the fuzzy c-meams (FCM) clustering algorithms to this data with a view towards identifying various states and stages of subjects experiencing such changes. Feature analysis, time step analysis, pooling data, response of the subjects, and the algorithms used are discussed.

  2. Hands, arms, and minds: interactions between posture and thought.

    PubMed

    Mohr, Christine; Thut, Gregor; Landis, Theodor; Brugger, Peter

    2003-10-01

    Based on earlier reports of inconsistent postural preferences in psychiatric populations, we assessed arm folding (AF) and hand clasping (HC) postures in 361 healthy right-handers with different degrees of magical ideation (MI). Subjects generally preferred the congruent combination of a left-arm-top (AF) and a left-thumb-top position (HC). Incongruent subjects, in particular those with a right-arm-top/left-thumb-top position, scored higher on MI than did congruent subjects. Our main finding was thus an association between a style of thinking (MI) and lateral preferences for limb postures, inconsistent across distal (primarily contralaterally innervated) and more proximal (more bilaterally innervated) parts of the body. This association is interpreted in the frame of lesser hemispheric asymmetries in subjects bordering to schizotypal personalities. PMID:13680446

  3. Significance of vestibular and proprioceptive afferentation in the regulation of human posture

    NASA Technical Reports Server (NTRS)

    Gurfinkel, V. S.

    1980-01-01

    Viewpoints on the vertical human posture and the relation between postural adaptation during voluntary movements and the guarantee of stable locomotor movements are examined. Various complex sensory systems are discussed.

  4. Effects of Four Days Hiking on Postural Control

    PubMed Central

    Vieira, Marcus Fraga; de Avelar, Ivan Silveira; Silva, Maria Sebastiana; Soares, Viviane; Lobo da Costa, Paula Hentschel

    2015-01-01

    Hiking is a demanding form of exercise that may cause delayed responses of the postural muscles and a loss of somatosensory information, particularly when repeatedly performed for several days. These effects may negatively influence the postural control of hikers. Therefore, the aim of this study was to investigate the effects of a four-day hike on postural control. Twenty-six adults of both sexes travelled 262 kilometers, stopping for lunch and resting in the early evening each day. Force platforms were used to collect center of pressure (COP) data at 100 Hz for 70 seconds before hiking started and immediately after arriving at the rest station each day. The COP time course data were analyzed according to global stabilometric descriptors, spectral analysis and structural descriptors using sway density curve (SDC) and stabilometric diffusion analysis (SDA). Significant increases were found for global variables in both the anterior-posterior and medial-lateral directions (COP sway area, COP total sway path, COP mean velocity, COP root mean square value and COP range). In the spectral analysis, only the 80% power frequency (F80) in the anterior-posterior direction showed a significant increase, reflecting the increase of the sway frequencies. The SDC revealed a significant increase in the mean distance between peaks (MD) and a significant decrease in the mean peak amplitudes (MP), suggesting that a larger torque amplitude is required for stabilization and that the postural stability is reduced. The SDA revealed a decrease in the long-term slope (Hl) and increases in the short-term (Ks) and the long-term (Kl) intercepts. We considered the likelihood that the presence of local and general fatigue, pain and related neuromuscular adaptations and somatosensory deficits may have contributed to these postural responses. Together, these results demonstrated that four days of hiking increased sway frequencies and deteriorated postural control in the standing position. PMID

  5. Postural motor learning in people with Parkinson's disease.

    PubMed

    Peterson, Daniel S; Dijkstra, Bauke W; Horak, Fay B

    2016-08-01

    Protective postural responses to external perturbations are hypokinetic in people with Parkinson's disease (PD), and improving these responses may reduce falls. However, the ability of people with PD to improve postural responses with practice is poorly understood. Our objective was to determine whether people with PD can improve protective postural responses similarly to healthy adults through repeated perturbations, and whether improvements are retained or generalize to untrained perturbations. Twelve healthy adults and 15 people with PD underwent 25 forward and 25 backward translations of the support surface, eliciting backward, and forward protective steps, respectively. We assessed whether: (1) performance improved over one day of practice, (2) changes were retained 24 h later, and (3) improvements generalized to untrained (lateral) postural responses. People with PD and healthy adults improved postural response characteristics, including center of mass displacement after perturbations (p < 0.001), margin of stability at first footfall (p = 0.001), step latency (p = 0.044), and number of steps (p = 0.001). However, unlike controls, improvements in people with PD occurred primarily in the first block of trials. Improvements were more pronounced during backward protective stepping than forward, and with the exception of step latency, were retained 24 h later. Improvements in forward-backward stepping did not generalize to lateral protective stepping. People with PD can improve protective stepping over the course of 1 day of perturbation practice. Improvements were generally similar to healthy adults, and were retained in both groups. Perturbation practice may represent a promising approach to improving protective postural responses in people with PD; however, additional research is needed to understand how to enhance generalization. PMID:27193311

  6. Quantifying and Reducing Posture-Dependent Distortion in Ballistocardiogram Measurements

    PubMed Central

    Javaid, Abdul Q.; Wiens, Andrew D.; Fesmire, N. Forrest; Weitnauer, Mary A.; Inan, Omer T.

    2015-01-01

    Ballistocardiography is a non-invasive measurement of the mechanical movement of the body caused by cardiac ejection of blood. Recent studies have demonstrated that ballistocardiogram (BCG) signals can be measured using a modified home weighing scale, and used to track changes in myocardial contractility and cardiac output. With this approach, the BCG can potentially be used both for preventive screening and for chronic disease management applications. However, for achieving high signal quality, subjects are required to stand still on the scale in an upright position for the measurement; the effects of intentional (for user comfort) or unintentional (due to user error) modifications in the position or posture of the subject during the measurement have not been investigated in the existing literature. In this study, we quantified the effects of different standing and seated postures on the measured BCG signals, and on the most salient BCG-derived features compared to reference standard measurements (e.g., impedance cardiography). We determined that the standing upright posture led to the least distorted signals as hypothesized, and that the correlation between BCG-derived timing interval features (R-J interval) and the pre-ejection period, PEP (measured using ICG), decreased significantly with impaired posture or sitting position. We further implemented two novel approaches to improve the PEP estimates from other standing and sitting postures, using system identification and improved J-wave detection methods. These approaches can improve the usability of standing BCG measurements in unsupervised settings (i.e. the home), by improving the robustness to non-ideal posture, as well as enabling high quality seated BCG measurements. PMID:26058064

  7. A Simple Postflight Measure of Postural Atania in Astronauts

    NASA Technical Reports Server (NTRS)

    Reschke, M. F.; Harm, D. I.; Kofman, I. S.; Wood, S. J.; Bloomberg, J. J.

    2011-01-01

    Astronauts returning from space flight universally present with postural ataxia. Throughout the Space Shuttle Program, measurement of ataxia has concentrated on sway in the anterior-posterior (AP) plane. The current investigation, as a part of a larger functional study, concentrated on characterizing postural instability using dynamic stabilographic sway patterns in both the AP and medial-lateral (ML) planes. To accomplish this goal, six astronauts from short-duration (Shuttle) and three from long-duration (ISS) flights were required to recover from a simulated fall. Subjects with eyes open, wearing running shoes lay prone on the floor for 2 minutes and then quickly stood up, maintained a quiet stance for 3 minutes, arms relaxed along the side of the body, and feet comfortably placed on the force plate. Crewmembers were tested twice before flight, on landing day (Shuttle only), and 1, 6, and 30 days after flight. Anterior-posterior and ML center-of-pressure (COP) coordinates were calculated from the ground reaction forces collected at 500 Hz. The 3-minute quiet stance trial was broken into three 1-minute segments for stabilogram diffusion analysis. A mean sway speed (rate of change of COP displacement) was also calculated as an additional postural stability parameter. While there was considerable variation, most of crewmembers tested exhibited increased stochastic activity evidenced by larger short-term COP diffusion coefficients postflight in both the AP and ML planes, suggesting significant changes in postural control mechanisms, particularly control of lower limb muscle function. As expected, postural instability of ISS astronauts on the first day postflight was similar to that of Shuttle crewmembers on landing day. Recoveries of stochastic activity and mean sway speed to baseline levels were typically observed by the 30th day postflight for both long-duration and short-duration crewmembers. Dynamic postural stability characteristics obtained in this low

  8. Longitudinal Study Evaluating Postural Balance of Young Athletes.

    PubMed

    Steinberg, Nili; Nemet, Dan; Pantanowitz, Michal; Zeev, Aviva; Hallumi, Monder; Sindiani, Mahmood; Meckel, Yoav; Eliakim, Alon

    2016-02-01

    Repeated anaerobic conditions during athletic performance may cause general and local fatigue that result in postural balance deficit. Evidence suggests that improved postural balance during athletic training may decrease the risk for fallings and traumatic injuries among athletes. Twenty athletes (12 girls, 8 boys) and 20 controls (12 girls, 8 boys) ages 10-15 years participated in the current study. All athletes were active in an 8-month physical activity program, 3 times per week for 90 min., specific to basketball, soccer, or athletic training. The control children participated in physical education at school only, with no involvement in organized extracurricular sports. All participants were evaluated for postural balance in three assessments over one year (at 4-mo intervals); the Interactive Balance System machine (Tetrax device) was used to assess balance at three test times (pre-, post-, and 10 min) after a session of a repeated sprint anaerobic test, consisting of 12 × 20 m run starting every 20 sec. The athletes had better postural balance than controls. There were different group patterns of change over the sessions; a significant interaction of session and group indicated that postural balance of the groups differed. The contribution of low sway frequencies (F1) and high sway frequencies (F6) differed between the controls and the athletes group. Results suggested that although athletes had better postural balance, improvement should be encouraged during training over the sessions and seasons, with special awareness of the balance deficit that occurs immediately after anaerobic stress and at the end of the season, to decrease the risk of injuries. PMID:27420320

  9. Effects of four days hiking on postural control.

    PubMed

    Vieira, Marcus Fraga; de Avelar, Ivan Silveira; Silva, Maria Sebastiana; Soares, Viviane; Lobo da Costa, Paula Hentschel

    2015-01-01

    Hiking is a demanding form of exercise that may cause delayed responses of the postural muscles and a loss of somatosensory information, particularly when repeatedly performed for several days. These effects may negatively influence the postural control of hikers. Therefore, the aim of this study was to investigate the effects of a four-day hike on postural control. Twenty-six adults of both sexes travelled 262 kilometers, stopping for lunch and resting in the early evening each day. Force platforms were used to collect center of pressure (COP) data at 100 Hz for 70 seconds before hiking started and immediately after arriving at the rest station each day. The COP time course data were analyzed according to global stabilometric descriptors, spectral analysis and structural descriptors using sway density curve (SDC) and stabilometric diffusion analysis (SDA). Significant increases were found for global variables in both the anterior-posterior and medial-lateral directions (COP sway area, COP total sway path, COP mean velocity, COP root mean square value and COP range). In the spectral analysis, only the 80% power frequency (F80) in the anterior-posterior direction showed a significant increase, reflecting the increase of the sway frequencies. The SDC revealed a significant increase in the mean distance between peaks (MD) and a significant decrease in the mean peak amplitudes (MP), suggesting that a larger torque amplitude is required for stabilization and that the postural stability is reduced. The SDA revealed a decrease in the long-term slope (Hl) and increases in the short-term (Ks) and the long-term (Kl) intercepts. We considered the likelihood that the presence of local and general fatigue, pain and related neuromuscular adaptations and somatosensory deficits may have contributed to these postural responses. Together, these results demonstrated that four days of hiking increased sway frequencies and deteriorated postural control in the standing position. PMID

  10. The force output of handle and pedal in different bicycle-riding postures.

    PubMed

    Chen, Chia-Hsiang; Wu, Yu-Kuang; Chan, Ming-Sheng; Shih, Yo; Shiang, Tzyy-Yuang

    2016-01-01

    The purpose of this study was to analyse the force output of handle and pedal as well as the electromyography (EMG) of lower extremity in different cycling postures. Bilateral pedalling asymmetry indices of force and EMG were also determined in this study. Twelve healthy cyclists were recruited for this study and tested for force output and EMG during steady state cycling adopting different pedalling and handle bar postures. The standing posture increased the maximal stepping torque (posture 1: 204.2 ± 47.0 Nm; posture 2: 212.5 ± 46.1 Nm; posture 3: 561.5 ± 143.0 Nm; posture 4: 585.5 ± 139.1 Nm), stepping work (posture 1: 655.2 ± 134.6 Nm; posture 2: 673.2 ± 116.3 Nm; posture 3: 1852.3 ± 394.4 Nm; posture 4: 1911.3 ± 432.9 Nm), and handle force (posture 1: 16.6 ± 3.6 N; posture 2: 16.4 ± 3.6 N; posture 3: 26.5 ± 8.2 N; posture 4: 41.4 ± 11.1 N), as well as muscle activation (posture 1: 13.6-25.1%; posture 2: 13.0-23.9%; posture 3: 23.6-61.8%; posture 4: 22.5-65.8%) in the erector spine, rectus femoris, tibialis anterior, and soleus. However, neither a sitting nor a standing riding posture affected the hamstring. The riding asymmetry was detected between the right and left legs only in sitting conditions. When a cyclist changes posture from sitting to standing, the upper and lower extremities are forced to produce more force output because of the shift in body weight. These findings suggest that cyclists can switch between sitting and standing postures during competition to increase cycling efficiency in different situations. Furthermore, coaches and trainers can modify sitting and standing durations to moderate cycling intensity, without concerning unbalanced muscle development. PMID:26967311

  11. 7 CFR 1755.507 - Aerial cable services.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... § 1755.507 Aerial cable services. (a) Where more than six pairs are needed initially, and where an aerial service is necessary, the service shall consist of 22 AWG filled aerial cable of a pair size adequate for... from the building, the wall bracket shall be reinforced against pullout by an arrangement equivalent...

  12. 7 CFR 1755.507 - Aerial cable services.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... § 1755.507 Aerial cable services. (a) Where more than six pairs are needed initially, and where an aerial service is necessary, the service shall consist of 22 AWG filled aerial cable of a pair size adequate for... from the building, the wall bracket shall be reinforced against pullout by an arrangement equivalent...

  13. 7 CFR 1755.507 - Aerial cable services.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... § 1755.507 Aerial cable services. (a) Where more than six pairs are needed initially, and where an aerial service is necessary, the service shall consist of 22 AWG filled aerial cable of a pair size adequate for... from the building, the wall bracket shall be reinforced against pullout by an arrangement equivalent...

  14. 47 CFR 32.6421 - Aerial cable expense.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Aerial cable expense. 32.6421 Section 32.6421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6421 Aerial cable expense. (a) This account shall include expenses associated with aerial cable. (b) Subsidiary record...

  15. 47 CFR 32.6421 - Aerial cable expense.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Aerial cable expense. 32.6421 Section 32.6421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6421 Aerial cable expense. (a) This account shall include expenses associated with aerial cable. (b) Subsidiary record...

  16. 47 CFR 32.6421 - Aerial cable expense.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Aerial cable expense. 32.6421 Section 32.6421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6421 Aerial cable expense. (a) This account shall include expenses associated with aerial cable. (b) Subsidiary record...

  17. 47 CFR 32.6421 - Aerial cable expense.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Aerial cable expense. 32.6421 Section 32.6421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6421 Aerial cable expense. (a) This account shall include expenses associated with aerial cable. (b) Subsidiary record...

  18. Geography via Aerial Field Trips: Do It This Way, 6.

    ERIC Educational Resources Information Center

    Richason, Benjamin F., Jr.; Guell, Carl E.

    To provide guidance for geography teachers, this booklet presents information on how to plan and execute aerial field trips. The aerial field trip can be employed as an effective visual aid technique in the teaching of geography, especially for presenting earth generalizations and interrelationships. The benefits of an aerial field trip are…

  19. The lumbosacral segment as a vulnerable region in various postures

    NASA Technical Reports Server (NTRS)

    Rosemeyer, B.

    1978-01-01

    The lumbosacral region in man is exposed to special static and dynamic load. In a supine position, the disc size increases because of the absence of axial load. In a standing position, with physiological posture of the spine, strain discomfort occurs which is increased even more in the sitting position due to the curvature of the lumbar region of the spine and the irregular distribution of pressure in the discs as a result of this. This special problem of sitting posture can be confirmed by examinations.

  20. Fetal malnutrition--the price of upright posture?

    PubMed Central

    Briend, A

    1979-01-01

    The pattern of preterm fetal growth faltering, normally seen in man, differs from that observed in animals. This type of fetal growth cannot be considered as an adaptation to facilitate birth but is more likely to be due to rapid evolution and imperfect adaptation to the upright posture. The pattern of posture and physical activity during pregnancy may therefore be an important determinant of fetal growth. Differences in intrauterine nutrition existing between social groups, usually ascribed to variations of maternal diet and nutrition, may well result from different patterns of maternal activity in the weeks preceding birth. PMID:476446

  1. The Effect of Body Posture on Brain Glymphatic Transport

    PubMed Central

    Lee, Hedok; Xie, Lulu; Yu, Mei; Kang, Hongyi; Feng, Tian; Deane, Rashid; Logan, Jean; Nedergaard, Maiken

    2015-01-01

    The glymphatic pathway expedites clearance of waste, including soluble amyloid β (Aβ) from the brain. Transport through this pathway is controlled by the brain's arousal level because, during sleep or anesthesia, the brain's interstitial space volume expands (compared with wakefulness), resulting in faster waste removal. Humans, as well as animals, exhibit different body postures during sleep, which may also affect waste removal. Therefore, not only the level of consciousness, but also body posture, might affect CSF–interstitial fluid (ISF) exchange efficiency. We used dynamic-contrast-enhanced MRI and kinetic modeling to quantify CSF-ISF exchange rates in anesthetized rodents' brains in supine, prone, or lateral positions. To validate the MRI data and to assess specifically the influence of body posture on clearance of Aβ, we used fluorescence microscopy and radioactive tracers, respectively. The analysis showed that glymphatic transport was most efficient in the lateral position compared with the supine or prone positions. In the prone position, in which the rat's head was in the most upright position (mimicking posture during the awake state), transport was characterized by “retention” of the tracer, slower clearance, and more CSF efflux along larger caliber cervical vessels. The optical imaging and radiotracer studies confirmed that glymphatic transport and Aβ clearance were superior in the lateral and supine positions. We propose that the most popular sleep posture (lateral) has evolved to optimize waste removal during sleep and that posture must be considered in diagnostic imaging procedures developed in the future to assess CSF-ISF transport in humans. SIGNIFICANCE STATEMENT The rodent brain removes waste better during sleep or anesthesia compared with the awake state. Animals exhibit different body posture during the awake and sleep states, which might affect the brain's waste removal efficiency. We investigated the influence of body posture on

  2. Hypertension associated with massive, bilateral, posture-dependent renal dysfunction

    SciTech Connect

    Clorius, J.H.; Schmidlin, P.; Raptou, E.; Huber, W.; Georgi, P.

    1981-07-01

    Hippurate function scintiscans were obtained in prone and standing positions in a group of 76 patients with concurrent hypertension and nephroptosis. Twelve of these patients had massive, bilateral disturbance of intrarenal hippurate transport in the standing position; hippurate transport was normal in the prone position. This pattern was present in only three of 120 normotensive patients with nephroptosis. To investigate the importance of nephroptosis, 87 other hypertensive patients were examined. Eighteen of these patients demonstrated posture-dependent tubular dysfunction, but only four had nephroptosis. The results suggest a direct relationship between bilateral posture-dependent tubular dysfunction and hypertension.

  3. [Pyridostigmine in the treatment of postural orthostatic tachycardia syndrome].

    PubMed

    Can, Ilknur; Tholakanahalli, Venkatakrishna

    2014-09-01

    A 34-year-old female patient was admitted with the complaints of inability to stand upright, palpitations, dizziness, and fatigue in the upright posture for the last one year. She was found to stand upright for less than one minute without symptoms. Tilt table testing showed that, compared to baseline her heart rate increased 55 beats/min in the fifth minute of the test with the symptoms of palpitations, fatigue and sweating without any significant change in her blood pressure. Postural orthostatic tachycardia syndrome was diagnosed, and pyridostigmine treatment was started. Four months after treatment her symptoms were relieved so that she was able to function as a nurse. PMID:25362946

  4. Aerial Infrared Photos for Citrus Growers

    NASA Technical Reports Server (NTRS)

    Blazquez, C. H.; Horn, F. W. J.

    1982-01-01

    Handbook advises on benefits and methods of aerial photography with color infrared film. Interpretation of photographs is discussed in detail. Necessary equipment for interpretation is described--light table, magnifying lenses, and microfiche viewers, for example. Advice is given on rating tree condition; identifying effects of diseases, insects, and nematodes; and evaluating effects of soil, water, and weather.

  5. "A" Is for Aerial Maps and Art

    ERIC Educational Resources Information Center

    Todd, Reese H.; Delahunty, Tina

    2007-01-01

    The technology of satellite imagery and remote sensing adds a new dimension to teaching and learning about maps with elementary school children. Just a click of the mouse brings into view some images of the world that could only be imagined a generation ago. Close-up aerial pictures of the school and neighborhood quickly catch the interest of…

  6. 29 CFR 1926.453 - Aerial lifts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from the American National...) Vertical towers; and (v) A combination of any such devices. Aerial equipment may be made of metal, wood... on the edge of the basket or use planks, ladders, or other devices for a work position. (v) A...

  7. 29 CFR 1926.453 - Aerial lifts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from the American National...) Vertical towers; and (v) A combination of any such devices. Aerial equipment may be made of metal, wood... on the edge of the basket or use planks, ladders, or other devices for a work position. (v) A...

  8. 29 CFR 1926.453 - Aerial lifts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from the American National...) Vertical towers; and (v) A combination of any such devices. Aerial equipment may be made of metal, wood... on the edge of the basket or use planks, ladders, or other devices for a work position. (v) A...

  9. Using Unmanned Aerial Vehicles and GPS Receivers

    NASA Technical Reports Server (NTRS)

    Gary, B.

    1995-01-01

    It is proposed that a small fleet of unmanned aerial vehicles (UAVs) be used over a period of years to monitor the rise of pressure surfaces caused by the hypothesized rise in average temperature of the troposphere due to global warming. Global Positioning Satellite System (GPS) receivers would be used for the precise tracking required.

  10. Sea Ice Mapping using Unmanned Aerial Systems

    NASA Astrophysics Data System (ADS)

    Solbø, S.; Storvold, R.

    2011-12-01

    Mapping of sea ice extent and sea ice features is an important task in climate research. Since the arctic coastal and oceanic areas have a high probability of cloud coverage, aerial platforms are superior to satellite measurements for high-resolution optical measurements. However, routine observations of sea ice conditions present a variety of problems using conventional piloted aircrafts. Specially, the availability of suitable aircrafts for lease does not cover the demand in major parts of the arctic. With the recent advances in unmanned aerial systems (UAS), there is a high possibility of establishing routine, cost effective aerial observations of sea ice conditions in the near future. Unmanned aerial systems can carry a wide variety of sensors useful for characterizing sea-ice features. For instance, the CryoWing UAS, a system initially designed for measurements of the cryosphere, can be equipped with digital cameras, surface thermometers and laser altimeters for measuring freeboard of ice flows. In this work we will present results from recent CryoWing sea ice flights on Svalbard, Norway. The emphasis will be on data processing for stitching together images acquired with the non-stabilized camera payload, to form high-resolution mosaics covering large spatial areas. These data are being employed to map ice conditions; including ice and lead features and melt ponds. These high-resolution mosaics are also well suited for sea-ice mechanics, classification studies and for validation of satellite sea-ice products.

  11. ENVIRONMENTAL APPLICATION OF LOW ALTITUDE AERIAL PHOTOGRAPHY

    EPA Science Inventory

    The most practical avenue for development of these goals is to continue to use the LAAPS system at field sites that require aerial imaging. For the sake of convenience, I believe that the local field sites can provide a convenient location to develop new applications and test enh...

  12. Aerial Scene Recognition using Efficient Sparse Representation

    SciTech Connect

    Cheriyadat, Anil M

    2012-01-01

    Advanced scene recognition systems for processing large volumes of high-resolution aerial image data are in great demand today. However, automated scene recognition remains a challenging problem. Efficient encoding and representation of spatial and structural patterns in the imagery are key in developing automated scene recognition algorithms. We describe an image representation approach that uses simple and computationally efficient sparse code computation to generate accurate features capable of producing excellent classification performance using linear SVM kernels. Our method exploits unlabeled low-level image feature measurements to learn a set of basis vectors. We project the low-level features onto the basis vectors and use simple soft threshold activation function to derive the sparse features. The proposed technique generates sparse features at a significantly lower computational cost than other methods~\\cite{Yang10, newsam11}, yet it produces comparable or better classification accuracy. We apply our technique to high-resolution aerial image datasets to quantify the aerial scene classification performance. We demonstrate that the dense feature extraction and representation methods are highly effective for automatic large-facility detection on wide area high-resolution aerial imagery.

  13. A TOOL FOR PLANNING AERIAL PHOTOGRAPHY

    EPA Science Inventory

    abstract The U.S. EPAs Pacific Coastal Ecology Branch has developed a tool in the form of an Excel. spreadsheet that facilitates planning aerial photography missions. The spreadsheet accepts various input parameters such as desired photo-scale and boundary coordinates of the stud...

  14. The Art and Science of Aerial Perspective

    ERIC Educational Resources Information Center

    Kegel, Susan

    2006-01-01

    The author is always looking for ways to see connections and to adapt experiences across different subjects. Combining art with other disciplines helps keep students engaged, even the really analytical and verbal learners. Aerial perspective is an art technique, a scientific principle, and a vehicle for introducing Chinese painting and…

  15. Calculating aerial images from EUV masks

    NASA Astrophysics Data System (ADS)

    Pistor, Thomas V.; Neureuther, Andrew R.

    1999-06-01

    Aerial images for line/space patterns, arrays of posts and an arbitrary layout pattern are calculated for EUV masks in a 4X EUV imaging system. Both mask parameters and illumination parameters are varied to investigate their effects on the aerial image. To facilitate this study, a parallel version of TEMPEST with a Fourier transform boundary condition was developed and run on a network of 24 microprocessors. Line width variations are observed when absorber thickness or sidewall angle changes. As the line/space pattern scales to smaller dimensions, the aspect ratios of the absorber features increase, introducing geometric shadowing and reducing aerial image intensity and contrast. 100nm square posts have circular images of diameter close to 100nm, but decreasing in diameter significantly when the corner round radius at the mask becomes greater than 50 nm. Exterior mask posts image slightly smaller and with higher ellipticity than interior mask posts. The aerial image of the arbitrary test pattern gives insight into the effects of the off-axis incidence employed in EUV lithography systems.

  16. The Control of Posture in Newly Standing Infants is Task Dependent

    ERIC Educational Resources Information Center

    Claxton, Laura J.; Melzer, Dawn K.; Ryu, Joong Hyun; Haddad, Jeffrey M.

    2012-01-01

    The postural sway patterns of newly standing infants were compared under two conditions: standing while holding a toy and standing while not holding a toy. Infants exhibited a lower magnitude of postural sway and more complex sway patterns when holding the toy. These changes suggest that infants adapt postural sway in a manner that facilitates…

  17. Assessment of Postural Control in Children with Cerebral Palsy: A Review

    ERIC Educational Resources Information Center

    Pavao, Silvia Leticia; dos Santos, Adriana Neves; Woollacott, Marjorie Hines; Rocha, Nelci Adriana Cicuto Ferreira

    2013-01-01

    This paper aimed to review studies that assessed postural control (PC) in children with cerebral palsy (CP) and describe the methods used to investigate postural control in this population. It also intended to describe the performance of children with CP in postural control. An extensive database search was performed using the keywords: postural…

  18. Onset of Dyskinesia and Changes in Postural Task Performance during the Course of Neuroleptic Withdrawal.

    ERIC Educational Resources Information Center

    Newell, Karl M.; Ko, Young G.; Sprague, Robert L.; Mahorney, Steven L.; Bodfish, James W.

    2002-01-01

    The effect of neuroleptic withdrawal on postural task performance of 20 adults with mental retardation was examined. Assessments were conducted at baseline and monthly intervals, extending to one year following complete medication withdrawal, when significant changes in amount of postural motion and sequential pattern of postural movement…

  19. Combining Workstation Design and Performance Management to Increase Ergonomically Correct Computer Typing Postures

    ERIC Educational Resources Information Center

    Culig, Kathryn M.; Dickinson, Alyce M.; Lindstrom-Hazel, Debra; Austin, John

    2008-01-01

    The effects of workstation changes and a performance management (PM) package on seven typing postures were examined for seven office workers. Workstation adjustments were implemented first. Two participants increased five safe postures by 50% or more. The effects of a PM package on postures that did not improve by 50% were then examined using a…

  20. Development of low postural tone compensatory patterns in children - theoretical basis.

    PubMed

    Gogola, Anna; Saulicz, Edward; Kuszewski, Michał; Matyja, Małgorzata; Myśliwiec, Andrzej

    2014-01-01

    Neurological literature indicates the existence of children with low postural tone without association with central nervous system damage. This fact induces to think about mechanisms, which allow these children to maintain upright posture. There is a suspicion that compensatory mechanism included in this process, enables to achieve upright posture, but at expense of body posture quality. Observations of children's developmental stages caused determination of some postural tone area, which comprise both children with normotonia and with low postural tone without characteristics of central nervous system (CNS) damage. Set of specific qualities allows determination of two types of low postural tone: spastoidal and atetoidal type. Spastoidal type is characterized by deep trunk muscles (local) low postural tone compensated by excessive tension of superficial muscles (global). Atetoidal type includes children with low postural tone in both deep and superficial muscles. At inefficient active subsystem, verticalization proceeds at excessive use of passive subsystem qualities, that is meniscus, ligament, bone shape, and muscles passive features. From neurodevelopmental point of view compensatory mechanisms can be used in children with low postural tone in order to achieve upright posture, but at expense of body posture quality. PMID:25182403

  1. Perceived body discomfort and trunk muscle activity in three prolonged sitting postures

    PubMed Central

    Waongenngarm, Pooriput; Rajaratnam, Bala S.; Janwantanakul, Prawit

    2015-01-01

    [Purpose] This study aimed to investigate the perceived discomfort and trunk muscle activity in three different 1-hour sitting postures. [Subjects] A repeated-measures design study was conducted on 10 healthy subjects. [Methods] Each subject sat for an hour in three sitting postures (i.e., upright, slumped, and forward leaning sitting postures). Subjects rated perceived body discomfort using Borg’s CR-10 scale at the beginning and after 1 hour sitting. The electromyographic activity of the trunk muscle activity was recorded during the 1-hour period of sitting. [Results] The forward leaning sitting posture led to higher Borg scores in the low back than those in the upright (p = 0.002) and slumped sitting postures (p < 0.001). The forward leaning posture was significantly associated with increased iliocostalis lumborum pars thoracis (ICL) and superficial lumbar multifidus (MF) muscle activity compared with the upright and slumped sitting postures. The upright sitting posture was significantly associated with increased internal oblique (IO)/transversus abdominis (TrA) and ICL muscle activity compared with the slumped sitting posture. [Conclusion] The sitting posture with the highest low back discomfort after prolonged sitting was the forward leaning posture. Sitting in an upright posture is recommended because it increases IO/TrA muscle activation and induces only relatively moderate ICL and MF muscle activation. PMID:26311951

  2. Object and activity detection from aerial video

    NASA Astrophysics Data System (ADS)

    Se, Stephen; Shi, Feng; Liu, Xin; Ghazel, Mohsen

    2015-05-01

    Aerial video surveillance has advanced significantly in recent years, as inexpensive high-quality video cameras and airborne platforms are becoming more readily available. Video has become an indispensable part of military operations and is now becoming increasingly valuable in the civil and paramilitary sectors. Such surveillance capabilities are useful for battlefield intelligence and reconnaissance as well as monitoring major events, border control and critical infrastructure. However, monitoring this growing flood of video data requires significant effort from increasingly large numbers of video analysts. We have developed a suite of aerial video exploitation tools that can alleviate mundane monitoring from the analysts, by detecting and alerting objects and activities that require analysts' attention. These tools can be used for both tactical applications and post-mission analytics so that the video data can be exploited more efficiently and timely. A feature-based approach and a pixel-based approach have been developed for Video Moving Target Indicator (VMTI) to detect moving objects at real-time in aerial video. Such moving objects can then be classified by a person detector algorithm which was trained with representative aerial data. We have also developed an activity detection tool that can detect activities of interests in aerial video, such as person-vehicle interaction. We have implemented a flexible framework so that new processing modules can be added easily. The Graphical User Interface (GUI) allows the user to configure the processing pipeline at run-time to evaluate different algorithms and parameters. Promising experimental results have been obtained using these tools and an evaluation has been carried out to characterize their performance.

  3. Attention Demand and Postural Control in Children with Hearing Deficit

    ERIC Educational Resources Information Center

    Derlich, Malgorzata; Krecisz, Krzysztof; Kuczynski, Michal

    2011-01-01

    To elucidate the mechanisms responsible for deteriorated postural control in children with hearing deficit (CwHD), we measured center-of-pressure (COP) variability, mean velocity and entropy in bipedal quiet stance (feet together) with or without the concurrent cognitive task (reaction to visual stimulus) on hard or foam surface in 29 CwHD and a…

  4. Task, muscle and frequency dependent vestibular control of posture

    PubMed Central

    Forbes, Patrick A.; Siegmund, Gunter P.; Schouten, Alfred C.; Blouin, Jean-Sébastien

    2015-01-01

    The vestibular system is crucial for postural control; however there are considerable differences in the task dependence and frequency response of vestibular reflexes in appendicular and axial muscles. For example, vestibular reflexes are only evoked in appendicular muscles when vestibular information is relevant to postural control, while in neck muscles they are maintained regardless of the requirement to maintain head on trunk balance. Recent investigations have also shown that the bandwidth of vestibular input on neck muscles is much broader than appendicular muscles (up to a factor of 3). This result challenges the notion that vestibular reflexes only contribute to postural control across the behavioral and physiological frequency range of the vestibular organ (i.e., 0–20 Hz). In this review, we explore and integrate these task-, muscle- and frequency-related differences in the vestibular system’s contribution to posture, and propose that the human nervous system has adapted vestibular signals to match the mechanical properties of the system that each group of muscles controls. PMID:25620919

  5. Effect of gravity and posture on lung mechanics.

    PubMed

    Bettinelli, D; Kays, C; Bailliart, O; Capderou, A; Techoueyres, P; Lachaud, J L; Vaïda, P; Miserocchi, G

    2002-12-01

    The volume-pressure relationship of the lung was studied in six subjects on changing the gravity vector during parabolic flights and body posture. Lung recoil pressure decreased by approximately 2.7 cmH(2)O going from 1 to 0 vertical acceleration (G(z)), whereas it increased by approximately 3.5 cmH(2)O in 30 degrees tilted head-up and supine postures. No substantial change was found going from 1 to 1.8 G(z). Matching the changes in volume-pressure relationships of the lung and chest wall (previous data), results in a decrease in functional respiratory capacity of approximately 580 ml at 0 G(z) relative to 1 G(z) and of approximately 1,200 ml going to supine posture. Microgravity causes a decrease in lung and chest wall recoil pressures as it removes most of the distortion of lung parenchyma and thorax induced by changing gravity field and/or posture. Hypergravity does not greatly affect respiratory mechanics, suggesting that mechanical distortion is close to maximum already at 1 G(z). The end-expiratory volume during quiet breathing corresponds to the mechanical functional residual capacity in each condition. PMID:12391116

  6. Posture as a Determinant of Visual Behavior in Newborns

    ERIC Educational Resources Information Center

    Fredrickson, W. Timm; Brown, Josephine V.

    1975-01-01

    The effects of posture on the visual behavior of 15 3-day-old healthy, black, newborn infants were assessed. Findings suggest that the vestibular, proprioceptive, and contact stimulation provided by the on-shoulder position affects the newborn's ability to follow and process visual stimuli. (Author/CS)

  7. Practice of Contemporary Dance Promotes Stochastic Postural Control in Aging

    PubMed Central

    Ferrufino, Lena; Bril, Blandine; Dietrich, Gilles; Nonaka, Tetsushi; Coubard, Olivier A.

    2011-01-01

    As society ages and the frequency of falls increases, counteracting gait and posture decline is a challenging issue for countries of the developed world. Previous studies have shown that exercise and hazard management help to improve balance and/or decrease the risks for falling in normal aging. Motor activity based on motor-skill learning, particularly dance, can also benefit balance and decreases falls with age. Recent studies have suggested that older dancers have better balance, posture, or gait than non-dancers. Additionally, clinical or laboratory measures have shown improvements in some aspects of balance after dance interventions in elderly trainees. This study examined the impact of contemporary dance (CD) and of fall prevention (FP) programs on postural control of older adults. Posturography of quiet upright stance was performed in 41 participants aged 59–86 years before and after 4.4-month training in either CD or FP once a week. Though classical statistic scores failed to show any effect, dynamic analyses of the center-of-pressure displacements revealed significant changes after training. Specifically, practice of CD enhanced the critical time interval in diffusion analysis, and reduced recurrence and mathematical stability in recurrence quantification analysis, whereas practice of FP induced or tended to induce the reverse patterns. Such effects were obtained only in the eyes open condition. We suggest that CD training based on motor improvisation favored stochastic posture inducing plasticity in motor control, while FP training based on more stereotyped behaviors did not. PMID:22232582

  8. Objective Clinical Assessment of Posture Patterns after Implant Breast Augmentation

    PubMed Central

    Mandrini, Silvia; Finotti, Valentina; Dall’Angelo, Anna; Malovini, Alberto; Chierico, Simona; Faga, Angela; Dalla Toffola, Elena

    2015-01-01

    Background: An increased weight of the breasts causes several spinal postural alterations that reduce the ability to perform dynamic tasks requiring a stable balance. The effects of the increased weight of the breasts on static posture after implant breast augmentation have not been investigated yet. Methods: Forty volunteer healthy women were asked to wear different sized breast implants (800, 400, and 300 g) inside a dedicated sports bra for 6½ consecutive hours during their everyday life activities, 1 day for every implant size. Posture changes were assessed with the association of a physiatric clinical examination with a static force platform analysis. Results: A significant increase in cervical lordosis after the use of 400-g breast implants and upward was demonstrated. This alteration was stable between the 400-g and 800-g breast implants. The 400-g (per breast) implant might therefore be the load threshold that breaks the cervical postural physiologic balance. A significant increase in lumbar lordosis was demonstrated only after the use of the 800-g breast implants. The static force platform assessment demonstrated a worsening of the balance independent from the visual control with the use of 400-g and 800-g implants. Conclusions: Heavy breast implants proved to induce reversible alterations in the spinal curve, and 400 g is the cutoff for functional physiologic compensation in the short term. Such a weight might be considered the safety limit for the use of breast implants for cosmetic purposes. PMID:26218390

  9. Evaluation of postural stability in children with hemiplegic cerebral palsy

    PubMed Central

    Kenis-Coskun, Ozge; Giray, Esra; Eren, Beyhan; Ozkok, Ozlem; Karadag-Saygi, Evrim

    2016-01-01

    [Purpose] Postural stability is the ability of to maintain the position of the body within the support area. This function is affected in cerebral palsy. The aim of the present study was to compare static and dynamic postural stability between children with hemiplegic cerebral palsy and healthy controls. [Subjects and Methods] Thirty-seven children between the ages of 5 and 14 diagnosed with hemiplegic cerebral palsy (19 right, 18 left) and 23 healthy gender- and age-matched controls were included in the study. Postural stability was evaluated in both of the groups using a Neurocom Balance. Sway velocity was measured both with the eyes open and closed. Sit to stand and turning abilities were also assessed. [Results] The sway velocities with the eyes open and closed were significantly different between the groups. The weight transfer time in the Sit to Stand test was also significantly slower in children with cerebral palsy. Children with cerebral palsy also showed slower turning times and greater sway velocities during the Step and Quick Turn test on a force plate compared with their healthy counterparts. [Conclusion] Both static and dynamic postural stability parameters are affected in hemiplegic cerebral palsy. Further research is needed to define rehabilitation interventions to improve these parameters in patients. PMID:27313338

  10. Closed loop kinesthetic feedback for postural control rehabilitation.

    PubMed

    Vérité, Fabien; Bachta, Wael; Morel, Guillaume

    2014-01-01

    Postural control rehabilitation may benefit from the use of smart devices providing biofeedback. This approach consists of increasing the patients perception of their postural state. Namely, postural state is monitored and fed back in real time to the patients through one or more sensory channels. This allows implementing rehabilitation exercises where the patients control their posture with the help of additional sensory inputs. In this paper, a closed loop control of the Center-Of-Pressure (CoP) based on kinesthetic feedback is proposed as a new form of biofeedback. The motion of a one Degree of Freedom (DoF) translational device, lightly touched by the patient's forefinger, is servoed to the patient's CoP position extracted from the measurements of a force plate on which he/she stands. As a result, the patient's CoP can be controllably displaced. A first set of experiments is used to prove the feasibility of this closed-loop control under ideal conditions favoring the perception of the kinesthetic feedback, while the subject is totally unaware of the context. A second set of experiments is then proposed to evaluate the robustness of this approach under experimental conditions that are more realistic with regards to the clinical context of a rehabilitation program involving biofeedback-based exercises. PMID:24968379

  11. Do Equilibrium Constraints Modulate Postural Reaction when Viewing Imbalance?

    ERIC Educational Resources Information Center

    Tia, Banty; Paizis, Christos; Mourey, France; Pozzo, Thierry

    2012-01-01

    Action observation and action execution are tightly coupled on a neurophysiological and a behavioral level, such that visually perceiving an action can contaminate simultaneous and subsequent action execution. More specifically, observing a model in postural disequilibrium was shown to induce an increase in observers' body sway. Here we…

  12. Influence of Passive Stiffness of Hamstrings on Postural Stability

    PubMed Central

    Kuszewski, Michał; Gnat, Rafał; Sobota, Grzegorz; Myśliwiec, Andrzej

    2015-01-01

    The aim of the study was to explore whether passive stiffness of the hamstrings influences the strategy of maintaining postural stability. A sample of 50 subjects was selected; the final analyses were based on data of 41 individuals (33 men, 8 women) aged 21 to 29 (mean = 23.3, SD = 1.1) years. A quasi- experimental ex post facto design with repeated measures was used. Categories of independent variables were obtained directly prior to the measurement of the dependent variables. In stage one of the study, passive knee extension was measured in the supine position to assess hamstring stiffness. In stage two, the magnitude of postural sway in antero-posterior direction was measured, while varying the body position on a stabilometric platform, both with and without visual control. The margin of safety was used as a measure of postural control. The magnitude of the margin of safety increased significantly between the open-eye and closed-eye trials. However, although we registered a visible tendency for a larger increase of the margin of safety associated with lower levels of passive hamstrings stiffness, no significant differences were found. Therefore, this study demonstrated that hamstring stiffness did not influence the strategy used to maintain postural stability. PMID:25964809

  13. Payload specialists Baudry and Al-Saud conduct Postural experiment

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Payload specialists Patrick Baudry (left) and Sultan Salman Abdelazize Al-Saud team up to conduct a French Postural Experement (FPE) on the middeck of the Space shuttle Discovery during the STS 51-G flight. Behind them on the middeck walls are two sleep restraints.

  14. Payload specialist Sultan Abdelazize Al-Saud conducts Postural experiment

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Payload specialist Sultan Salman Abdelazize Al-Saud assists in conducting a French Postural Experement (FPE) on the middeck of the Space shuttle Discovery during the STS 51-G flight. Behind him on the middeck walls are two sleep restraints. At the bottom of the frame, foot restraints are visible.

  15. Enhancing Anticipatory Postural Adjustments: A Novel Approach to Balance Rehabilitation

    PubMed Central

    Aruin, Alexander S.

    2016-01-01

    Balance impairment is common in individuals with neurological disorders and older adults and is a major cause of falls in these populations. Evidence on the effectiveness of conventional interventions for balance restoration is limited. We describe a novel approach to balance rehabilitation that is based on enhancing anticipatory postural adjustments. PMID:27335705

  16. Training affects the development of postural adjustments in sitting infants.

    PubMed Central

    Hadders-Algra, M; Brogren, E; Forssberg, H

    1996-01-01

    1. The present study addressed the question of whether daily balance training can affect the development of postural adjustments in sitting infants. 2. Postural responses during sitting on a moveable platform were assessed in twenty healthy infants at 5-6, 7-8 and 9-10 months of age. Multiple surface EMGs and kinematics were recorded while the infants were exposed to slow and fast horizontal forward (Fw) and backward (Bw) displacements of the platform. After the first session the parents of nine infants trained their child's sitting balance daily. 3. At the youngest age, when none of the infants could sit independently, the muscle activation patterns were direction specific and showed a large variation. This variation decreased with increasing age, resulting in selection of the most complete responses. Training facilitated response selection both during Fw and Bw translations. This suggests a training effect on the first level of the central pattern generator (CPG) model of postural control. 4. Training also affected the development of response modulation during Fw translations. It accelerated the development of: (1) the ability to modulate EMG amplitude with respect to platform velocity and initial sitting position, (2) antagonist activity and (3) a distal onset of the response. These findings point to a training effect on the second level of the CPG model of postural adjustments. Images Figure 1 Figure 4 PMID:8735713

  17. Radiation Dose Estimation Using Realistic Postures with PIMAL

    SciTech Connect

    Akkurt, Hatice; Wiarda, Dorothea; Eckerman, Keith F

    2010-12-01

    For correct radiation dose assessment, it is important to take the posture into account. A computational phantom with moving arms and legs was previously developed to address this need. Further, an accompanying graphical user interface (GUI), called PIMAL, was developed to enable dose estimation using realistic postures in a user-friendly manner such that the analyst's time could be substantially reduced. The importance of the posture for correct dose estimation has been demonstrated with a few case studies in earlier analyses. The previous version of PIMAL was somewhat limited in its features (i.e., it contained only a hermaphrodite phantom model and allowed only isotropic source definition). Currently GUI is being further enhanced by incorporating additional phantom models, improving the features, and increasing the user friendliness in general. This paper describes recent updates to the PIMAL software. In this summary recent updates to the PIMAL software, which aims to perform radiation transport simulations for phantom models in realistic postures in a user-friendly manner, are described. In future work additional phantom models, including hybrid phantom models, will be incorporated. In addition to further enhancements, a library of input files for the case studies that have been analyzed to date will be included in the PIMAL.

  18. Slow Dangerous Curve: Scoliosis and Posture Screening Handbook. Revised Edition.

    ERIC Educational Resources Information Center

    Tenney, Horace K., III; And Others

    The yearly screening process to detect scoliosis (curvature of the spine) and poor posture in girls 10 to 14 and boys 13 to 14 is discussed. The purpose of the program is to detect deformities in their earliest stages to prevent progression. Photographs are interspersed with text on suggestions for planning the screening program, clothing, setting…

  19. Postural Control in Children, Teenagers and Adults with Down Syndrome

    ERIC Educational Resources Information Center

    Rigoldi, Chiara; Galli, Manuela; Mainardi, Luca; Crivellini, Marcello; Albertini, Giorgio

    2011-01-01

    The goal of this work was to analyze postural control in Down syndrome (DS) participants considering three different groups composed by children, teenagers and adults with DS. An analysis of the centre of pressure (COP) displacement during standing position was therefore performed for the three groups of subjects. The obtained signal of COP was…

  20. Returning home: location memory versus posture memory in object manipulation.

    PubMed

    Weigelt, Matthias; Cohen, Rajal; Rosenbaum, David A

    2007-05-01

    Previous studies of object manipulation have suggested that when participants return an object to the place from which they just carried it, they tend to grasp the object for the target-back-to-home trips close to where they just grasped it for the home-to-target trips [Exp Brain Res 157(4):486-495, 2004; Psychon Bull Rev, 2006]. What was unclear from these previous studies was whether participants recalled postures or locations. According to the posture hypothesis, they remembered what body positions they adopted when they last held the object. According to the location hypothesis, they remembered where they held the object and then took hold of it there or nearby again. To distinguish between these possibilities, we had participants mount or dismount a platform after home-to-target moves and before target-back-to-home moves. In the control condition, they did not change their vertical position relative to the shelf containing the home and target platforms (they merely stepped sideways). We found that participants grasped the object at nearly the same place along its length as they had before, even if this meant adopting very different postures than before. This outcome is consistent with the location-recall account and is inconsistent with the posture-recall account. The implications for motor planning are discussed. PMID:17119941

  1. Motivational Postures and Compliance with Environmental Law in Australian Agriculture

    ERIC Educational Resources Information Center

    Bartel, Robyn; Barclay, Elaine

    2011-01-01

    Motivational posture theory is applied and extended to the context of Australian agriculture and environmental regulation. Regulatory failure in this area has been observed but little was known of the compliance attitudes and behaviours of farmers prior to this study. Agriculture covers over 60% of Australia's land surface so this information is…

  2. Emotion and motivated behavior: postural adjustments to affective picture viewing.

    PubMed

    Hillman, Charles H; Rosengren, Karl S; Smith, Darin P

    2004-03-01

    Thirty-six participants (18 female, 18 male) viewed affective pictures to investigate the coupling between emotional reactions and motivated behavior. Framed within the biphasic theory of emotion, the three systems approach was employed by collecting measures of subjective report, expressive physiology, and motivated behavior. Postural adjustments associated with viewing affective pictures were measured. Results indicated sex-differences for postural responses to unpleasant pictures; an effect not found for pleasant and neutral picture contents. Females exhibited increased postural movement in the posterior direction, and males exhibited increased movement in the anterior direction, for unpleasant pictures. Subjective report of valence and arousal using the self-assessment manikin (SAM), and the startle eye-blink reflex were collected during a separate session, which replicated previous picture-viewing research. Specifically, participants rated pleasant pictures higher in valence and exhibited smaller startle responses compared to unpleasant pictures. Females also reported lower valence ratings compared to males across all picture contents. These findings extend our knowledge of motivated engagement with affective stimuli and indicate that postural responses may provide insight into sex-related differences in withdrawal behavior. PMID:15019170

  3. Changes of postural steadiness following use of prefabricated orthotic insoles.

    PubMed

    Bateni, Hamid

    2013-04-01

    Orthoses are designed to assist a malaligned foot in adapting to the environment and reduce the frequency of injury. Literature is divided on the benefits of orthotics insoles for postural stability. The current study was conducted to determine the effect of prefabricated orthotic arch supports on postural stabilization. Twelve healthy young adults participated in this study and were tested with and without prefabricated orthotics. Different variables were computed from movement of center of pressure (COP) during orthotic use as suggested in the literature. The mean position of COP was significantly shifted forward and toward the dominant side. Neither the COP movement nor the velocity changes following the use of orthotics revealed significant differences. Mediolateral range of COP movement and the 95% confidence circle area of sway was significantly reduced (P = .022 and 0.048 respectively), but changes in 95% confidence circle and ellipse areas of fractal dimension were not significant (P = .053 and P = .057 respectively). In conclusion, orthotic insoles significantly improved postural sway initially by reducing mediolateral range of postural sway and 95% confidence circle area of sway at the cost of increased fractal dimension area variables and power. PMID:22815281

  4. Changes in the body posture of women occurring with age

    PubMed Central

    2013-01-01

    Background A current topic in the field of geriatrics still needing a great deal of study is the changes in body posture occurring with age. Symptoms of these changes can be observed starting between the ages of 40–50 years with a slow progression that increases after 60 years of age. The aims of this study were to evaluate parameters characterizing the posture of women over the age of 60 years compared with a control group and to determine the dynamics of body posture changes in the following decades. Methods The study included 260 randomly selected women. The study group consisted of 130 women between the ages of 60–90 years (Older Women). The control group (Younger Women) consisted of 130 women between the ages of 20–25 years (posture stabilization period). The photogrammetric method was used to evaluate body posture using the phenomenon of the projection chamber. The study was conducted according to generally accepted principles. Results In the analysis of parameters characterizing individual slope curves, results were varied among different age groups. The lumbar spine slope did not show significant differences between different age groups (p = 0.6952), while statistically significant differences (p = 0.0000) were found in the thoracic-lumbar spine slope (p = 0.0033) and upper thoracic spine slope. Body angle was shown to increase with age (p = 0.0000). Thoracic kyphosis depth significantly deepened with age (p = 0.0002), however, the thoracic kyphosis angle decreased with age (p = 0.0000). An increase in asymmetries was noticed, provided by a significantly higher angle of the shoulder line (p = 0.0199) and the difference in height of the lower shoulder blade angle (p = 0.0007) measurements in the group of older women. Conclusions Changes in the parameters describing body posture throughout consecutive decades were observed. Therapy for women over the age of 60 years should involve strengthening of the erector spinae

  5. INFLUENCE OF INJURY ON DYNAMIC POSTURAL CONTROL IN RUNNERS

    PubMed Central

    Klusendorf, Anna; Kernozek, Thomas

    2016-01-01

    ABSTRACT Background Injury has been linked with altered postural control in active populations. The association between running injury and dynamic postural control has not been examined. Hypothesis/Purpose The purpose of this study was to examine dynamic postural control in injured and uninjured runners using the Star Excursion Balance Test (SEBT), Time to Stabilization (TTS) of ground reaction forces following a single-leg landing, and postural stability indices reflecting the fluctuations in GRFs during single-leg landing and stabilization tasks (forward and lateral hop). It was hypothesized that dynamic postural control differences would exist between runners with a history of injury that interrupted training for ≥7 days (INJ) when compared to runners without injury (CON). Design Case-control study Methods Twenty-two INJ (14 F, 8 M; 23.7 ± 2.1 y; 22.3 ± 2.8 kg/m2; 29.5 ± 16.3 mi/wk) currently running > 50% pre-injury mileage without pain were compared with twenty-two matched CON (14F, 8M; 22.7 ± 1.2 y; 22.7 ± 2.7 kg/m2; 31.2 ± 19.6 mi/wk). INJ group was stratified by site of injury into two groups (Hip/Thigh/Knee and Lower Leg/Ankle/Foot) for secondary analysis. Leg length-normalized anterior, posterolateral, and posteromedial reach distances on the SEBT, medial/lateral and anterior/posterior ground reaction force TTS, directional postural stability indices, and a composite dynamic postural stability index (DPSI), were assessed using mixed model ANOVA (α=0.05) and effect sizes (d). Results No group X direction interaction or group differences were observed for the SEBT (p=0.51, 0.71) or TTS (p=0.83, 0.72) measures. A group X direction interaction was found for postural stability indices during the forward landing task (p<0.01). Both Hip/Thigh/Knee and Lower leg/Ankle/Foot INJ groups demonstrated a greater vertical postural stability index (VPSI) (p=0.01 for both, d=0.80, 0.95) and DPSI (p=0.01, 0.02, d=0.75, 0.93) when

  6. Modulation of plasma melatonin concentrations by changes in posture.

    PubMed

    Nathan, P J; Jeyaseelan, A S; Burrows, G D; Norman, T R

    1998-05-01

    Posture change from a lying position to a standing position results in a decrease in plasma volume, which leads to an increase in plasma constituents, especially that of proteins and blood constituents bound to them. The aim of the present study was to investigate the physiological effects of postural changes on plasma nocturnal melatonin concentrations in healthy human volunteers. The study was divided into four stages. During stage one, subjects were seated from 21.00 hr to 01.00 hr. In stage two, subjects were lying at ground level from 21.00 hr to 01.00 hr. In stage three, subjects were is a sitting position from 2100 hr to 2300 hr and then in a standing position from 23.00 hr to 24.00 hr, and back to the sitting position from 24.00 hr to 01.00 hr. In the final stage, subjects were in a lying position from 21.00 hr to 23.00 hr and then in a standing position from 23.00 hr to 24.00 hr and back to the lying position from 24.00 hr to 01.00 hr. AUC analysis showed significant differences between sitting and lying positions (t=2.84; P<0.05; df=5), with higher melatonin levels associated with the sitting position (mean difference in peak concentration of 17.1 pg/ml). Furthermore a change in posture from the lying to the standing position produced a statistically significant increase in melatonin concentrations (final stage) (t=-3.37; P<0.05; df=5) (mean difference in peak concentration of 28.5 pg/ml). No differences were found with a change in posture from a sitting to a standing position. The hemoconcentration and hemodilution associated with posture changes may play a role in altering plasma protein bound hormones such as melatonin. PMID:9572531

  7. Postural Assessment Software (PAS/SAPO): Validation and Reliabiliy

    PubMed Central

    Ferreira, Elizabeth Alves G.; Duarte, Marcos; Maldonado, Edison Puig; Burke, Thomaz Nogueira; Marques, Amelia Pasqual

    2010-01-01

    OBJECTIVE: This study was designed to estimate the accuracy of the postural assessment software (PAS/SAPO) for measurement of corporal angles and distances as well as the inter- and intra-rater reliabilities. INTRODUCTION: Postural assessment software was developed as a subsidiary tool for postural assessment. It is easy to use and available in the public domain. Nonetheless, validation studies are lacking. METHODS: The study sample consisted of 88 pictures from 22 subjects, and each subject was assessed twice (1 week interval) by 5 blinded raters. Inter- and intra-rater reliabilities were estimated using the intraclass correlation coefficient. To estimate the accuracy of the software, an inanimate object was marked with hallmarks using pre-established parameters. Pictures of the object were rated, and values were checked against the known parameters. RESULTS: Inter-rater reliability was excellent for 41% of the variables and very good for 35%. Ten percent of the variables had acceptable reliability, and 14% were defined as non-acceptable. For intra-rater reliability, 44.8% of the measurements were considered to be excellent, 23.5% were very good, 12.4% were acceptable and 19.3% were considered non-acceptable. Angular measurements had a mean error analisys of 0.11°, and the mean error analisys for distance was 1.8 mm. DISCUSSION: Unacceptable intraclass correlation coefficient values typically used the vertical line as a reference, and this may have increased the inaccuracy of the estimates. Increased accuracies were obtained by younger raters with more sophisticated computer skills, suggesting that past experience influenced results. CONCLUSION: The postural assessment software was accurate for measuring corporal angles and distances and should be considered as a reliable tool for postural assessment. PMID:20668624

  8. Lateral ankle ligament anesthesia significantly alters single limb postural control.

    PubMed

    McKeon, P O; Booi, M J; Branam, B; Johnson, D L; Mattacola, C G

    2010-07-01

    Lateral ankle anesthesia has been used as a model to explore effects of ligament deafferentation related to ankle sprain on single limb postural control with conflicting results. Time-to-boundary (TTB) is a postural control measurement technique found to be sensitive in detecting subtle deficits in postural control in those with chronic ankle instability. The objective of this study was to determine the effects of lateral ankle ligament anesthesia on TTB measures of single limb postural control in healthy adults. Twenty-two healthy adults with no history of lower extremity injury within the past 6 months or balance disorders participated in the study. All subjects received a lidocaine injection to the lateral ankle structures on one of two testing days. On both testing days, subjects performed 3 eyes open and 3 eyes closed, 10-s trials of barefoot single limb stance on a forceplate. The dependent variables were the mean of TTB minima(s) and standard deviation of TTB minima(s) in mediolateral (ML) and anteroposterior (AP) directions. Separate condition (anesthesia, control) by vision (eyes open, eyes closed) ANOVAs with repeated measures were used for each TTB variable to determine the effects of anesthesia on postural control. Alpha level was set a priori at p≤0.05. The anesthesia day TTBAP magnitude (p=0.008) and variability (p=0.044) measures were significantly lower than the control day, regardless of vision. Anesthesia of the lateral ankle ligamentous structures significantly reduced the magnitude and variability of TTBAP measures. These findings are similar to deficits found in those with chronic ankle instability. PMID:20663671

  9. Support afferentation in the posture and locomotion control system

    NASA Astrophysics Data System (ADS)

    Grigoriev, Anatoly; Tomilovskaya, Elena; Kozlovskaya, Inesa

    Mechanisms of support afferentation contribution in posture and locomotion control, which were uncertain up to now, became the point of intensive studies recently. This became possible since the space flights era started which created the conditions for simulated microgravity experiments under conditions of dry immersion and bedrest. The results of neurophysiological studies performed under the conditions of supportlessness have shown that decline or elimination of support loads is followed by deep and fast developing alterations in postural tonic system, including development of postural muscle atonia, changes of recruitment order of motoneurons innervating the shin muscles, spinal hyperreflexia development etc. (Kozlovskaya I.B. et al., 1987). It has been also shown that application of artificial support stimulation in the regimen of natural locomotion under these conditions decreases significantly or even eliminates the development of mentioned changes. The results of these studies laid down the basis for a new hypothesis on the trigger role of support afferentation in postural tonic system and its role in organization and control of postural synergies (Grigoriev A.I. et al., 2004). According to this hypothesis the muscle reception is considered to be the leading afferent input in the control of locomotion. However the data of recent studies pointed out strongly to the participation of support afferentation in definition of cognitive strategies and motor programs of locomotor movements (Chernikova L.A. et al., 2013) and, consequently, in the processes of their initiation (Gerasimenko Yu.P. et al., 2012). The cortical locomotor reflex composes apparently the basis of these processes. The receptive field of this reflex is located in the support zones of the soles and the central part is located in the posterior parietal areas (IPL) of brain cortex. The study is supported by RFBR grant N 13-04-12091 OFI-m.

  10. Comparison of Postural Recovery Following Short and Long Duration Spaceflights

    NASA Technical Reports Server (NTRS)

    Wood, S. J.; Fiedler, J.; Taylor, L. C.; Kozlovskaya, I.; Black, F. O.; Paloski, W. H.

    2010-01-01

    INTRODUCTION: Post-flight postural ataxia reflects adaptive changes to vestibulo-spinal reflexes and control strategies adopted for movement in weightlessness. Quantitative measures obtained during computerized dynamic posturography (CDP) from US and Russian programs provide insight into the effect of spaceflight duration in terms of both the initial decrements and recovery of postural stability. METHODS: CDP was obtained on 117 crewmembers following Shuttle flights lasting 4-17 days, and on 64 crewmembers following long-duration missions lasting 48-380 days. Although the number and timing of sessions varied, the goal was to characterize postural recovery pooling similar measures from different research and flight medicine programs. This report focuses on eyes closed, head erect conditions with either a fixed or sway-referenced base of support. A smaller subset of subjects repeated the sway-referenced condition while making pitch head movements (+/- 20deg at 0.33Hz). Equilibrium scores were derived from peak-to-peak anterior-posterior sway. Fall probability was modeled using Bayesian statistical methods to estimate parameters of a logit function. RESULTS: The standard Romberg condition was the least sensitive. Longer duration flights led to larger decrements in stability with sway-reference support during the first 1-2 days, although the timecourse of recovery was similar across flight duration with head erect. Head movements led to increased incidence of falls during the first week, with a significantly longer recovery following long duration flights. CONCLUSIONS: The diagnostic assessment of postural instability, and differences in the timecourse of postural recovery between short and long flight durations, are more pronounced during unstable support conditions requiring active head movements.

  11. Effects of adiposity on postural control and cognition.

    PubMed

    Meng, Hao; O'Connor, Daniel P; Lee, Beom-Chan; Layne, Charles S; Gorniak, Stacey L

    2016-01-01

    In the U.S., it is estimated that over one-third of adults are obese (Body Mass Index (BMI)>30kg/m(2)). Previous studies suggest that obesity may be associated with deficits in cognitive performance and postural control. Increased BMI may challenge cognitive and postural performance in a variety of populations; however, most relevant studies have classified participants based on BMI values, which cannot be used to accurately assess the effects of adiposity on cognitive performance and postural control. The objective of the current study was to examine motor and cognitive responses for overweight and obese adults compared to normal weight individuals by using both BMI and adiposity measures. Ten normal weight (BMI=18-24.9kg/m(2)), ten overweight (BMI=25-29.9kg/m(2)), and ten obese (BMI=30-40kg/m(2)) adults were evaluated (age: 24±4 years). Participants were classified into three groups based on BMI values at the onset of the study, prior to body composition analysis. Participants performed (1) working memory task while maintaining upright stance, and (2) a battery of sensorimotor evaluations. Working memory reaction times, response accuracy, center-of-pressure (COP) path length, velocity, migration area, time to boundary values in anterior-posterior direction, and ankle-hip strategy-scores were calculated to evaluate cognitive-motor performance. No significant deficits in working memory performance were observed. Overall, measures of motor function deteriorated as BMI and body fat percentage increased. The relationship between deteriorating postural performance indices and body fat percentage were greater than those found between BMI and postural performance indices. PMID:26669948

  12. Mechanical Characteristics of Reflex Durign Upright Posture in Paralyzed Subjects

    NASA Astrophysics Data System (ADS)

    Kim, Yongchul; Youm, Youngil; Lee, Bumsuk; Kim, Youngho; Choi, Hyeonki

    The characteristics of flexor reflexes have been investigated in the previous studies with human subjects who were seated or supine position. However, researchers did not describe how the spinal circuits are used in different hip angles for paralyzed subjects, such as the standing position with walker or cane. In upright posture the compatibility between a flexor reflex of leg and body balance is a special problem for lower limb injured subjects. Therefore, the purpose of this study was to investigate the effects of hip angle change on the flexor reflex evoked in standing paralyzed subjects supported by walker. In this study, six spinal cord injured and four stroke subjects were recruited through the inpatient physical therapy clinics of Korea national rehabilitation hospital. A single axis electronic goniometer was mounted on the lateral side of the hip joint of the impaired limb to record movements in the sagittal plane at this joint. The electronic goniometer was connected to a data acquisition system, through amplifiers to a computer. Since subject' posture influenced characteristics of the flexion reflex response, the subjects were supported in an upright posture by the help of parallelogram walder. Two series of tests were performed on each leg. The first series of the tests investigated the influence of hip angle during stationary standing posture on flexion reflex response. The hip angle was adjusted by the foot plate. The second examined the effect of the voluntary action of subject on swing motion during the gait. The electrically induced flexion reflex simultaneously produced the flexion of the hip, knee and dorsiflexion of the ankle enabling the swing phase of walking. Form the experimental results we observed that the reflex response of hip joint was largerwith the hip in the extended position than in the flexed position during standing posture. Under voluntary movement on flexion reflex during gaint, the peak hip angle induced by stimulation was

  13. Effects of scapular stabilization exercise on neck posture and muscle activation in individuals with neck pain and forward head posture

    PubMed Central

    Im, Boyoung; Kim, Young; Chung, Yijung; Hwang, Sujin

    2016-01-01

    [Purpose] The purpose of this study was to investigate the effects of scapular stabilization exercise on neck posture, muscle activity, pain, and quality of life in individuals with neck pain and forward head posture. [Subjects and Methods] Fifteen participants were recruited according to the selection criteria and were randomly allocated to the scapular stabilization group (n=8) and the control group (n=7). The scapular stabilization group underwent training for 30 minutes a day, 3 times a week for 4 weeks; the control group performed relaxation exercises for 4 weeks. [Results] After training the scapular stabilization group showed significant improvement on the craniovertebral angle, upper trapezius muscle activity, serratus anterior muscle activity, Neck Disability Index scores, Visual Analog Scale scores, and World Health Organization Quality of Life Assessment-BREF scores compared to those in the control group. [Conclusion] Scapular stabilization exercise can help improve the head posture and pain in the patients with neck pain and forward head posture. Controlling the muscular activities through scapular stabilization exercise also improves the patients’ quality of life. PMID:27134391

  14. Characterization of posture and comfort in laptop users in non-desk settings.

    PubMed

    Gold, J E; Driban, J B; Yingling, V R; Komaroff, E

    2012-03-01

    Laptop computers may be used in a variety of postures not coupled to the office workstation. Using passive motion analysis, this study examined mean joint angles during a short typing/editing task in college students (n=20), in up to seven positions. Comfort was assessed after task execution through a body map. For three required postures, joint angles in a prone posture were different than those while seated at a couch with feet either on floor or on ottoman. Specifically, the prone posture was characterized by comparatively non-neutral shoulders, elbows and wrists, and pronounced neck extension. Significantly greater intensity and more regions of discomfort were marked for the prone posture than for the seated postures. It is recommended that the prone posture only be assumed briefly during laptop use. Exposure to laptops outside of the office setting should be assessed in future epidemiologic studies of musculoskeletal complaints and computer use. PMID:21726854

  15. Comparison of visual and vibrotactile feedback methods for seated posture guidance.

    PubMed

    Zheng, Ying Jean; Morrell, John B

    2013-01-01

    We introduce a novel posture guidance office chair and evaluate the effectiveness of vibrotactile and visual feedback methods for guiding seated postures. For visually dominant office work such as typing on the computer, it is possible that delivering posture feedback visually may overload the visual sense while haptic feedback may be a viable alternative. We performed two experiments to compare vibrotactile and visual feedback--posture compliance and dual-task cognitive workload assessment. In the first experiment, our results showed no statistically significant difference in effectiveness between using vibrotactile and visual feedback to obtain postural compliance to a reference posture. In the second experiment, participants experienced typing performance and response time degradations from both types of feedback. However the differences in performance degradation were not statistically significant between the two feedback methods. We conclude that vibrotactile and visual feedback are similarly effective for guiding quasistatic postures in routine tasks such as seated office work. PMID:24808264

  16. Posture recognition based on fuzzy logic for home monitoring of the elderly.

    PubMed

    Brulin, Damien; Benezeth, Yannick; Courtial, Estelle

    2012-09-01

    We propose in this paper a computer vision-based posture recognition method for home monitoring of the elderly. The proposed system performs human detection prior to the posture analysis; posture recognition is performed only on a human silhouette. The human detection approach has been designed to be robust to different environmental stimuli. Thus, posture is analyzed with simple and efficient features that are not designed to manage constraints related to the environment but only designed to describe human silhouettes. The posture recognition method, based on fuzzy logic, identifies four static postures and is robust to variation in the distance between the camera and the person, and to the person's morphology. With an accuracy of 74.29% of satisfactory posture recognition, this approach can detect emergency situations such as a fall within a health smart home. PMID:22997188

  17. Aerial measurement of heat loss: Phase II

    SciTech Connect

    Not Available

    1982-07-01

    The purpose of the program described was to develop techniques to reduce or eliminate some of the variables associated with thermogram analysis in order to provide more objective interpretation of the data collected with greater potential for accuracy. A procedure is given for measuring temperature which accounts for atmospheric, background, and differential emissivity effects. The residual error was found to be 1.0/sup 0/C. A technique was then identified and developed for determining heat loss lovels from roof top surface temperature data. A thermal integrity factor was defined as a function of insulation level and thermostat setting. Comparing these thermal integrity factors with aerial thermography data indicates that aerial thermography can be used to objectively and confidently define heat loss levels from building roofs. (LEW)

  18. Aerial color infrared photography applications to citriculture

    NASA Technical Reports Server (NTRS)

    Blazquez, C. H.; Horn, F. W., Jr.

    1980-01-01

    Results of a one-year experimental study on the use of aerial color infrared photography in citrus grove management are presented. It is found that the spring season, when trees are in flush (have young leaves), is the best season to photograph visible differences between healthy and diseased trees. It is also shown that the best photography can be obtained with a 12-in. focal length lens. The photographic scale that allowed good photo interpretation with simple inexpensive equipment was 1 in. = 330 ft. The use of a window-overlay transparency method allowed rapid photo interpretation and data recording in computer-compatible forms. Aerial color infrared photography carried out during the spring season revealed a more accurate status of tree condition than visual inspection.

  19. Controller Design of Quadrotor Aerial Robot

    NASA Astrophysics Data System (ADS)

    Yali, Yu; SunFeng; Yuanxi, Wang

    This paper deduced the nonlinear dynamic model of a quadrotor aerial robot, which was a VTOL (vertical tale-off and landing) unmanned air vehicle. Since that is a complex model with the highly nonlinear multivariable strongly coupled and under-actuated property, the controller design of it was very difficult. Aimed at attaining the excellent controller, the whole system can be divided into three interconnected parts: attitude subsystem, vertical subsystem, position subsystem. Then nonlinear control strategy of them has been described, such as SDRE and Backstepping. The controller design was presented to stabilize the whole system. Through simulation result indicates, the various models have shown that the control law stabilize a quadrotor aerial robot with good tracking performance and robotness of the system.

  20. Effects of aging and tactile stochastic resonance on postural performance and postural control in a sensory conflict task.

    PubMed

    Dettmer, Marius; Pourmoghaddam, Amir; Lee, Beom-Chan; Layne, Charles S

    2015-01-01

    Postural control in certain situations depends on functioning of tactile or proprioceptive receptors and their respective dynamic integration. Loss of sensory functioning can lead to increased risk of falls in challenging postural tasks, especially in older adults. Stochastic resonance, a concept describing better function of systems with addition of optimal levels of noise, has shown to be beneficial for balance performance in certain populations and simple postural tasks. In this study, we tested the effects of aging and a tactile stochastic resonance stimulus (TSRS) on balance of adults in a sensory conflict task. Nineteen older (71-84 years of age) and younger participants (22-29 years of age) stood on a force plate for repeated trials of 20 s duration, while foot sole stimulation was either turned on or off, and the visual surrounding was sway-referenced. Balance performance was evaluated by computing an Equilibrium Score (ES) and anterior-posterior sway path length (APPlength). For postural control evaluation, strategy scores and approximate entropy (ApEn) were computed. Repeated-measures ANOVA, Wilcoxon signed-rank tests, and Mann-Whitney U-tests were conducted for statistical analysis. Our results showed that balance performance differed between older and younger adults as indicated by ES (p = 0.01) and APPlength (0.01), and addition of vibration only improved performance in the older group significantly (p = 0.012). Strategy scores differed between both age groups, whereas vibration only affected the older group (p = 0.025). Our results indicate that aging affects specific postural outcomes and that TSRS is beneficial for older adults in a visual sensory conflict task, but more research is needed to investigate the effectiveness in individuals with more severe balance problems, for example, due to neuropathy. PMID:25884289