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Sample records for tension leg platform

  1. 33 CFR 147.827 - Marlin Tension Leg Platform safety zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Marlin Tension Leg Platform... SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.827 Marlin Tension Leg Platform safety zone. (a) Description. The Marlin Tension Leg Platform (Marlin TLP), Viasca Knoll, Block 915 (VK...

  2. 33 CFR 147.837 - Marco Polo Tension Leg Platform safety zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Marco Polo Tension Leg Platform... SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.837 Marco Polo Tension Leg Platform safety zone. (a) Description. Marco Polo Tension Leg Platform, Green Canyon 608 (GC 608), located...

  3. 33 CFR 147.809 - Mars Tension Leg Platform safety zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Mars Tension Leg Platform safety... SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.809 Mars Tension Leg Platform safety zone. (a) Description. The Mars Tension Leg Platform (Mars TLP) is located at position 28°10′10.29...

  4. Brazil and the application of extended tension leg platform technology

    Energy Technology Data Exchange (ETDEWEB)

    Chianis, John W.; Jun Zou [ABB Floating Production Systems, Houston, TX (United States)

    2004-07-01

    Although there are several options for deep water development, the TLP has proven itself to be the system of choice for dry completion. This is demonstrated by its current worldwide application in the North Sea, Gulf of Mexico, West Africa and SE Asia. Future developments in Brazil are well suited to this Operator-friendly system. Also, due to the compact nature of its hull form, fabrication and integration of the system can be performed locally. TLPs represent a safe and proven solution for PETROBRAS in their quest to go deeper. As an introduction, this paper first addresses the basic principals of the TLP such as its superior motion characteristics and associated operational advantages, mooring system, hull form, and more. The paper will then present the more essential advancements in technology applied on the three most recent TLP projects including extension of water depth, high top tensioned riser counts, quay side integration, 'design one, build two', etc. Lastly and most importantly, other technology developments pertinent to near-term applications in Brazil are presented. (author)

  5. Update on the Comparison of Second-Order Loads on a Tension Leg Platform for Wind Turbines: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Gueydon, Sebastien; Jonkman, Jason

    2016-08-01

    In comparison to other kinds of floaters (like a spar or a semisubmersible), the tension leg platform has several notable advantages: its vertical motions are negligible, its weight is lighter, and its mooring system's footprint is smaller. Although a tension leg platform has a negligible response to first-order vertical wave loads, the second-order wave loads need to be addressed. This paper follows up on a verification study of second-order wave loads on a tension leg platform for wind turbines done by the Maritime Research Institute of The Netherlands and National Renewable Energy Laboratory and it brings some corrections to its conclusions.

  6. Performance Calculation of Floating Wind Turbine Tension Leg Platform in the South China Sea

    Directory of Open Access Journals (Sweden)

    Hai Feng Wang

    2015-10-01

    Full Text Available The harvesting of wind energy is expected to increase greatly in the future because of its stability, abundance, and renewability in large coastal states such as China. The floating support structure will likely become the major structural form for wind turbines in the future due to its cost advantages when the water depth reaches 50 m. The 5MW wind turbine model from National Renewable Energy Lab (NREL and the modified tension leg platform model proposed by Harbin Institute of Technology (HIT were applied to certain sea conditions in the South China Sea in order to consider the effects of external load coupling actions. In this study, the internal force, mooring system force, as well as the acceleration, displacement and velocity of the floating structure of the modified HIT Tension Leg Platform (HIT-TLP were calculated. During this process, the physical parameters of its tension leg structure at a specific frequency domain were obtained to find the technical reserves for its practical application in the future.

  7. An Investigation of Stress-Corrosion Cracking Susceptibility in Candidate Steels for Tension Leg Platform Tendons.

    Science.gov (United States)

    1986-04-24

    5773 An Investigation of Stress-Corrosion Cracking Susceptibility in Candidate Steels for Tension Leg Platform Tendons I. A. HAUSER II AND T. W. CROOKER...distribution unlimited. 4. PEfaOMIN 00GAZT1OM REPOT NIJMSER(S S. MONITORIN ORGAtsIZATIO61 REPWR NUMBEA(S NRL Memorandum Report 5773 Ga. NAME Of PFOROMIN...Fujil, "Stress-Corrosion Cracking Properties of 17-4 PH Steel", Stress Corrosion--New Approaches, ASTM STP 610, American Society for Testing and

  8. Preliminary Design of Offshore Wind Turbine Tension Leg Platform In the South China Sea

    Directory of Open Access Journals (Sweden)

    Hai-feng Wang

    2013-12-01

    Full Text Available China has the richest offshore wind resource in the world. Much of undeveloped resource should consider floating tension leg platform (TLP wind turbine because of its advantage and potential in cost and safety for deep sea, but the related research is short in China. In this thesis we assess a preliminary design for a type of TLP structure in the South China Sea (SCS-TLP closed to Guangdong province basing on NREL 5MW wind turbine. By coupled analysis in the time domain, the platform displacement and tower base force are obtained and analyzed. As a result, SCS-TLP has good features in the dynamic response except yaw motion, it needs to improve the yaw direction damping to induce motion in this direction.

  9. Fully Coupled Three-Dimensional Dynamic Response of a Tension-Leg Platform Floating Wind Turbine in Waves and Wind

    DEFF Research Database (Denmark)

    Kumari Ramachandran, Gireesh Kumar Vasanta; Bredmose, Henrik; Sørensen, Jens Nørkær

    2014-01-01

    A dynamic model for a tension-leg platform (TLP) floating offshore wind turbine is proposed. The model includes three-dimensional wind and wave loads and the associated structural response. The total system is formulated using 17 degrees of freedom (DOF), 6 for the platform motions and 11 for the...

  10. Small scale experimental study of the dynamic response of a tension leg platform wind turbine

    DEFF Research Database (Denmark)

    Hansen, Anders Mandrup; Laugesen, Robert; Bredmose, Henrik

    2014-01-01

    A floating Tension Leg Platform (TLP) wind turbine was constructed at scale 1/200 and its dynamic response was analysed experimentally in co-directional wind and waves. The wind turbine was Froude scaled and a new rotor was designed to yield maximum power and Froude scaled thrust at the low model...... wind speeds and irregular sea states as well as a range of regular waves. It was found that an increase in wind speed reduces the wave-induced floater motion but causes slightly larger nacelle displacements. Further, the orientation of the spokes relative to the direction of wind and waves influences...... the pitch stiffness and thereby the nacelle displacements. Inclining the tendons towards the wind turbine reduces the nacelle displacements significantly and reduces the occurrence of slack tendons, but increases the inline tilt-motion of the rotor. Application of a very stiff mooring configuration...

  11. Spoke Dimension on the Motion Performance of a Floating Wind Turbine with Tension-Leg Platform

    Directory of Open Access Journals (Sweden)

    H. F. Wang

    2016-01-01

    Full Text Available The tension-leg platform (TLP supporting structure is a good choice for floating offshore wind turbines because TLP has superior motion dynamics. This study investigates the effects of TLP spoke dimensions on the motion of a floating offshore wind turbine system (FOWT. Spoke dimension and offshore floating TLP were subjected to irregular wave and wind excitation to evaluate the motion of the FOWT. This research has been divided into two parts: (1 Five models were designed based on different spoke dimensions, and aerohydroservo-elastic coupled analyses were conducted on the models using the finite element method. (2 Considering the coupled effects of the dynamic response of a top wind turbine, a supporting-tower structure, a mooring system, and two models on a reduced scale of 1 : 80 were constructed and experimentally tested under different conditions. Numerical and experimental results demonstrate that the spoke dimensions have a significant effect on the motion of FOWT and the experimental result that spoke dimension can reduce surge platform movement to improve turbine performance.

  12. Model Development and Loads Analysis of a Wind Turbine on a Floating Offshore Tension Leg Platform

    Energy Technology Data Exchange (ETDEWEB)

    Matha, D.; Fischer, T.; Kuhn, M.; Jonkman, J.

    2010-02-01

    This report presents results of the analysis of a 5-MW wind turbine located on a floating offshore tension leg platform (TLP) that was conducted using the fully coupled time-domain aero-hydro-servo-elastic design code FAST with AeroDyn and HydroDyn. Models in this code are of greater fidelity than most of the models that have been used to analyze floating turbines in the past--which have neglected important hydrodynamic and mooring system effects. The report provides a description of the development process of a TLP model, which is a modified version of a Massachusetts Institute of Technology design derived from a parametric linear frequency-domain optimization process. An extensive loads and stability analysis for ultimate and fatigue loads according to the procedure of the International Electrotechnical Commission offshore wind turbine design standard was performed with the verified TLP model. Response statistics, extreme event tables, fatigue lifetimes, and selected time histories of design-driving extreme events are analyzed and presented. Loads for the wind turbine on the TLP are compared to those of an equivalent land-based turbine in terms of load ratios. Major instabilities for the TLP are identified and described.

  13. The Effect of Additional Mooring Chains on the Motion Performance of a Floating Wind Turbine with a Tension Leg Platform

    Directory of Open Access Journals (Sweden)

    Jinping Ou

    2012-04-01

    Full Text Available In this study, two types of floating offshore wind turbine (FOWT systems were proposed: a traditional tension leg platform (TLP type and a new TLP type with additional mooring chains. They were both based on the National Renewable Energy Laboratory 5 MW offshore wind turbine model. Taking the coupled effect of dynamic response of the top wind turbine, tower support structure and lower mooring system into consideration, not only were the 1/60 scale model tests for the two floating wind turbine systems done in HIT’s wind-wave tunnel according to the typical design conditions in IEC61400-3 code, but also the numerical simulations corresponding to the scaled model tests were performed by advanced numerical tools. As a result, the numerical results displayed good agreement with the test data. Moreover, the additional mooring chains could play an active role in reducing the surge displacement, surge acceleration and typical tension leg force responses of the FOWT system, which is very beneficial for ensuring the good operational performance and the safety of the FOWT system.

  14. Performance of a Single Liquid Column Damper for the Control of Dynamic Responses of a Tension Leg Platform

    Science.gov (United States)

    Jaksic, V.; Wright, C.; Chanayil, Afeef; Faruque Ali, Shaikh; Murphy, Jimmy; Pakrashi, Vikram

    2015-07-01

    Tuned liquid column dampers have been proved to be successful in mitigating the dynamic responses of civil infrastructure. There have been some recent applications of this concept on wind turbines and this passive control system can help to mitigate responses of offshore floating platforms and wave devices. The control of dynamic responses of these devices is important for reducing loads on structural elements and facilitating operations and maintenance (O&M) activities. This paper outlines the use of a tuned single liquid column damper for the control of a tension leg platform supported wind turbine. Theoretical studies were carried out and a scaled model was tested in a wave basin to assess the performance of the damper. The tests on the model presented in this paper correspond to a platform with a very low natural frequency for surge, sway and yaw motions. For practical purposes, it was not possible to tune the liquid damper exactly to this frequency. The consequent approach taken and the efficiency of such approach are presented in this paper. Responses to waves of a single frequency are investigated along with responses obtained from wave spectra characterising typical sea states. The extent of control is quantified using peak and root mean squared dynamic responses respectively. The tests present some guidelines and challenges for testing scaled devices in relation to including response control mechanisms. Additionally, the results provide a basis for dictating future research on tuned liquid column damper based control on floating platforms.

  15. Effect of second-order and fully nonlinear wave kinematics on a tension-leg-platform wind turbine in extreme wave conditions

    DEFF Research Database (Denmark)

    Pegalajar Jurado, Antonio Manuel; Borg, Michael; Robertson, Amy

    2017-01-01

    In this study, we assess the impact of different wave kinematics models on the dynamic response of a tension-leg-platform wind turbine. Aero-hydro-elastic simulations of the floating wind turbine are carried out employing linear, second-order, and fully nonlinear kinematics using the Morison equa...

  16. Parametric study on the behavior of an innovative subsurface tension leg platform in ultra-deep water

    Science.gov (United States)

    Zhen, Xing-wei; Huang, Yi

    2017-10-01

    This study focuses on a new technology of Subsurface Tension Leg Platform (STLP), which utilizes the shallowwater rated well completion equipment and technology for the development of large oil and gas fields in ultra-deep water (UDW). Thus, the STLP concept offers attractive advantages over conventional field development concepts. STLP is basically a pre-installed Subsurface Sea-star Platform (SSP), which supports rigid risers and shallow-water rated well completion equipment. The paper details the results of the parametric study on the behavior of STLP at a water depth of 3000 m. At first, a general description of the STLP configuration and working principle is introduced. Then, the numerical models for the global analysis of the STLP in waves and current are presented. After that, extensive parametric studies are carried out with regarding to SSP/tethers system analysis, global dynamic analysis and riser interference analysis. Critical points are addressed on the mooring pattern and riser arrangement under the influence of ocean current, to ensure that the requirements on SSP stability and riser interference are well satisfied. Finally, conclusions and discussions are made. The results indicate that STLP is a competitive well and riser solution in up to 3000 m water depth for offshore petroleum production.

  17. Comparison of Second-Order Loads on a Tension-Leg Platform for Wind Turbines: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Gueydon, S.; Wuillaume, P.; Jonkman, J.; Robertson, A.; Platt, A.

    2015-03-01

    The first objective of this work is to compare the two floating offshore wind turbine simulation packages {DIFFRAC+aNySIM} and {WAMIT+FAST}. The focus is on second-order wave loads, and so first- and second-order wave loads are applied to a structure sequentially for a detailed comparison and a more precise analysis of the effects of the second-order loads. aNySIM does not have the capability to model flexible bodies, and so the simulations performed in this tool are done assuming a rigid body. FAST also assumes that the platform is rigid, but can account for the flexibility of the tower. The second objective is to study the effects of the second-order loads on the response of a TLP floating wind turbine. The flexibility of the tower must be considered for this investigation, and therefore only FAST is used.

  18. Numerical Prediction of Experimentally Observed Behavior of a Scale Model of an Offshore Wind Turbine Supported by a Tension-Leg Platform: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Prowell, I.; Robertson, A.; Jonkman, J.; Stewart, G. M.; Goupee, A. J.

    2013-01-01

    Realizing the critical importance the role physical experimental tests play in understanding the dynamics of floating offshore wind turbines, the DeepCwind consortium conducted a one-fiftieth-scale model test program where several floating wind platforms were subjected to a variety of wind and wave loading condition at the Maritime Research Institute Netherlands wave basin. This paper describes the observed behavior of a tension-leg platform, one of three platforms tested, and the systematic effort to predict the measured response with the FAST simulation tool using a model primarily based on consensus geometric and mass properties of the test specimen.

  19. Model Development and Loads Analysis of an Offshore Wind Turbine on a Tension Leg Platform with a Comparison to Other Floating Turbine Concepts: April 2009

    Energy Technology Data Exchange (ETDEWEB)

    Matha, D.

    2010-02-01

    This report presents results of the analysis of a 5-MW wind turbine located on a floating offshore tension leg platform (TLP) that was conducted using the fully coupled time-domain aero-hydro-servo-elastic design code FAST with AeroDyn and HydroDyn. The report also provides a description of the development process of the TLP model. The model has been verified via comparisons to frequency-domain calculations. Important differences have been identified between the frequency-domain and time-domain simulations, and have generated implications for the conceptual design process. An extensive loads and stability analysis for ultimate and fatigue loads according to the procedure of the IEC 61400-3 offshore wind turbine design standard was performed with the verified TLP model. This report compares the loads for the wind turbine on the TLP to those of an equivalent land-based turbine. Major instabilities for the TLP are identified and described.

  20. Effect of Second-Order and Fully Nonlinear Wave Kinematics on a Tension-Leg-Platform Wind Turbine in Extreme Wave Conditions: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Amy N [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jonkman, Jason [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Pegalajar-Jurado, Antonio [Technical University of Denmark; Borg, Michael [Technical University of Denmark; Bredmose, Henrik [Technical University of Denmark

    2017-08-02

    In this study, we assess the impact of different wave kinematics models on the dynamic response of a tension-leg-platform wind turbine. Aero-hydro-elastic simulations of the floating wind turbine are carried out employing linear, second-order, and fully nonlinear kinematics using the Morison equation for the hydrodynamic forcing. The wave kinematics are computed from either theoretical or measured signals of free-surface elevation. The numerical results from each model are compared to results from wave basin tests on a scaled prototype. The comparison shows that sub and superharmonic responses can be introduced by second-order and fully nonlinear wave kinematics. The response at the wave frequency range is better reproduced when kinematics are generated from the measured surface elevation. In the future, the numerical response may be further improved by replacing the global, constant damping coefficients in the model by a more detailed, customizable definition of the user-defined numerical damping.

  1. Effect of Second-Order and Fully Nonlinear Wave Kinematics on a Tension-Leg-Platform Wind Turbine in Extreme Wave Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Amy N [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jonkman, Jason [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Pegalajar-Jurado, Antonio [Technical University of Denmark; Borg, Michael [Technical University of Denmark; Bredmose, Henrik [Technical University of Denmark

    2017-06-03

    In this study, we assess the impact of different wave kinematics models on the dynamic response of a tension-leg-platform wind turbine. Aero-hydro-elastic simulations of the floating wind turbine are carried out employing linear, second-order, and fully nonlinear kinematics using the Morison equation for the hydrodynamic forcing. The wave kinematics are computed from either theoretical or measured signals of free-surface elevation. The numerical results from each model are compared to results from wave basin tests on a scaled prototype. The comparison shows that sub and superharmonic responses can be introduced by second-order and fully nonlinear wave kinematics. The response at the wave frequency range is better reproduced when kinematics are generated from the measured surface elevation. In the future, the numerical response may be further improved by replacing the global, constant damping coefficients in the model by a more detailed, customizable definition of the user-defined numerical damping.

  2. Design of Structure of Tension Leg Platform for 6 MW Offshore Wind Turbine Based On Fem Analysis

    Directory of Open Access Journals (Sweden)

    Żywicki Jędrzej

    2017-04-01

    Full Text Available The article presents the calculation and design stages of the TLP platform serving as a supporting construction of a 6 MW offshore wind turbine. This platform is designed to anchor at sea at a depth of 60 m. The authors presented the method of parameterization and optimization of the hull geometry. For the two selected geometry variants, the load and motion calculations of the platform subjected to wind, wave and current under 50-year storm conditions were performed. The maximum load on the structure was determined in these extreme storm conditions. For these loads, the MES calculation of the designed platform was performed for the selected variant. Authors have presented a method for calculating maximum wind, wave and current stresses on the structure during the worst storm in the past 50 years. For these loads the MES endurance calculations of the designed platform were made. Based on the results of these calculations, the required structural changes and recalculations have been made in succession to the structural design of the platform, which meets the design requirements and has the required ad hoc strength. The article contains stress analysis in „difficult“ nodes of constructions and discusses ways of solving their problems. The work is part of the WIND-TU-PLA project from the NCBR Research Agreement (Agreement No. MARTECII / 1/2014.

  3. Use of Forward Scattering Particle Image Velocimetry to Quantify a Flow Field Near a Fully Submerged Tension Leg Platform in the Presence of Waves

    Science.gov (United States)

    2012-05-01

    sway (left and right) components of each particle are quantified by arrow length and direction, and the surge (forwards and backwards) component of...enable use of these potentiometers. The spring reels lines were oriented in the surge (x-plane), sway (y-plane), and heave (z-plane) planes of the...platform depth of 30cm. 0 The TLP is allowed to surge only. 0 Some numerical damping is used near the outlet to avoid reflection of the waves 0 10 flow

  4. Calibration and Validation of a FAST Floating Wind Turbine Model of the DeepCwind Scaled Tension-Leg Platform: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, G.; Lackner, M.; Robertson, A.; Jonkman, J.; Goupee, A.

    2012-05-01

    With the intent of improving simulation tools, a 1/50th-scale floating wind turbine atop a TLP was designed based on Froude scaling by the University of Maine under the DeepCwind Consortium. This platform was extensively tested in a wave basin at MARIN to provide data to calibrate and validate a full-scale simulation model. The data gathered include measurements from static load tests and free-decay tests, as well as a suite of tests with wind and wave forcing. A full-scale FAST model of the turbine-TLP system was created for comparison to the results of the tests. Analysis was conducted to validate FAST for modeling the dynamics of this floating system through comparison of FAST simulation results to wave tank measurements. First, a full-scale FAST model of the as-tested scaled configuration of the system was constructed, and this model was then calibrated through comparison to the static load, free-decay, regular wave only, and wind-only tests. Next, the calibrated FAST model was compared to the combined wind and wave tests to validate the coupled hydrodynamic and aerodynamic predictive performance. Limitations of both FAST and the data gathered from the tests are discussed.

  5. Calcul des efforts de deuxième ordre à très haute fréquence sur des plates-formes à lignes tendues Computing High-Frequency Second Order Loads on Tension Leg Platforms

    Directory of Open Access Journals (Sweden)

    Chen X.

    2006-11-01

    Full Text Available Le problème considéré ici est celui de l'évaluation des efforts excitateurs de deuxième ordre (en mode somme, c'est-à-dire prenant place aux sommes deux à deux des fréquences de houle sur des plates-formes à lignes tendues. Ces efforts sont tenus pour responsables de comportements résonnants (en roulis, tangage et pilonnement observés lors d'essais en bassin et pourraient réduire sensiblement la durée de vie en fatigue des tendons. Des résultats sont tout d'abord présentés pour une structure simplifiée, consistant en 4 cylindres verticaux reposant sur le fond marin. L'intérêt de cette géométrie est que tous les calculs peuvent être menés à terme de façon quasi analytique. Les résultats obtenus permettent d'illustrer le haut degré d'interaction entre les colonnes, et la faible décroissance du potentiel de diffraction de deuxième ordre avec la profondeur. On présente ensuite des résultats pour une plate-forme réelle, celle de Snorre. Tension Leg Platforms (TLP's are now regarded as a promising technology for the development of deep offshore fields. As the water depth increases however, their natural periods of heave, roll and pitch tend to increase as well (roughly to the one-half power, and it is not clear yet what the maximum permissible values for these natural periods can be. For the Snorre TLP for instance, they are only about 2. 5 seconds, which seems to be sufficiently low since there is very limited free wave energy at such periods. Model tests, however, have shown some resonant response in sea states with peak periods of about 5 seconds. Often referred to as springing , this resonant motion can severely affect the fatigue life of tethers and increase their design loads. In order to calculate this springing motion at the design stage, it is necessary to identify and evaluate both the exciting loads and the mechanisms of energy dissipation. With the help of the French Norwegian Foundation a joint effort was

  6. Model test of an inverted conical cylinder floating offshore wind turbine moored by a spring-tensioned-leg

    Directory of Open Access Journals (Sweden)

    Hyunkyoung Shin

    2014-03-01

    Full Text Available A new 5-MW floating offshore wind turbine moored by a spring-tensioned-leg was proposed for installation in about 50m water depth. Its substructure is a platform of the inverted conical cylinder type with massive ballast weight plate at the bottom. A 1:128 scale model was built for the preliminary engineering development. The model tests in waves and wind were carried out to estimate motion characteristics of this platform in the Ocean Engineering Wide Tank of the University of Ulsan. Its motions were measured and the RAOs were compared. The proposed floating offshore wind turbine showed a good stability and decent responses in waves, wind and operation of the wind turbine.

  7. Model test of an inverted conical cylinder floating offshore wind turbine moored by a spring-tensioned-leg

    Science.gov (United States)

    Shin, Hyunkyoung; Cho, Sangrai; Jung, Kwangjin

    2014-03-01

    A new 5-MW floating offshore wind turbine moored by a spring-tensioned-leg was proposed for installa­tion in about 50m water depth. Its substructure is a platform of the inverted conical cylinder type with massive ballast weight plate at the bottom. A 1:128 scale model was built for the preliminary engineering development. The model tests in waves and wind were carried out to estimate motion characteristics of this platform in the Ocean Engineering Wide Tank of the University of Ulsan. Its motions were measured and the RAOs were compared. The proposed floating off­shore wind turbine showed a good stability and decent responses in waves, wind and operation of the wind turbine.

  8. Model test of an inverted conical cylinder floating offshore wind turbine moored by a spring-tensioned-leg

    Directory of Open Access Journals (Sweden)

    Shin Hyunkyoung

    2014-03-01

    Full Text Available A new 5-MW floating offshore wind turbine moored by a spring-tensioned-leg was proposed for installa­tion in about 50m water depth. Its substructure is a platform of the inverted conical cylinder type with massive ballast weight plate at the bottom. A 1:128 scale model was built for the preliminary engineering development. The model tests in waves and wind were carried out to estimate motion characteristics of this platform in the Ocean Engineering Wide Tank of the University of Ulsan. Its motions were measured and the RAOs were compared. The proposed floating off­shore wind turbine showed a good stability and decent responses in waves, wind and operation of the wind turbine.

  9. Coupled dynamic response analysis of a multi-column tension-leg-type floating wind turbine

    Science.gov (United States)

    Zhao, Yong-sheng; Yang, Jian-min; He, Yan-ping; Gu, Min-tong

    2016-07-01

    This paper presents a coupled dynamic response analysis of a multi-column tension-leg-type floating wind turbine (WindStar TLP system) under normal operation and parked conditions. Wind-only load cases, wave-only load cases and combined wind and wave load cases were analyzed separately for the WindStar TLP system to identify the dominant excitation loads. Comparisons between an NREL offshore 5-MW baseline wind turbine installed on land and the WindStar TLP system were performed. Statistics of selected response variables in specified design load cases (DLCs) were obtained and analyzed. It is found that the proposed WindStar TLP system has small dynamic responses to environmental loads and it thus has almost the same mean generator power output under operating conditions as the land-based system. The tension mooring system has a sufficient safety factor, and the minimum tendon tension is always positive in all selected DLCs. The ratio of ultimate load of the tower base fore-aft bending moment for the WindStar TLP system versus the land-based system can be as high as 1.9 in all of the DLCs considered. These results will help elucidate the dynamic characteristics of the proposed WindStar TLP system, identify the difference in load effect between it and land-based systems, and thus make relevant modifications to the initial design for the WindStar TLP system.

  10. A space tethered towing method using tension and platform thrusts

    Science.gov (United States)

    Meng, Zhongjie; Wang, Bingheng; Huang, Panfeng

    2017-01-01

    Orbit maneuver via tether is a promising countermeasure for space debris removal and satellite orbit transfer. A space tethered towing method is explored that utilizes thrust to fulfill transfer and bounded tension to stabilize tether heading. For this purpose, a time-energy optimal orbit is designed by Gauss pseudospectral method. The theoretical attitude commands are obtained by equilibria analysis. An effective attitude control strategy is presented where the commands are optimized first and then feedback controller is designed. To deal with the underactuated problem with tension constraint, hierarchical sliding mode theory is employed and an adaptive anti-windup module is added to mitigate the actuator saturation. Simulation results show that the target is towed effectively by the thrusts, and a smooth tracking for the commands of tether length and in-plane tether heading is guaranteed by the bounded tension. In addition, the designed controller also presents appreciable robustness to model error and determination error.

  11. A miniature surface tension-driven robot using spatially elliptical moving legs to mimic a water strider's locomotion.

    Science.gov (United States)

    Yan, J H; Zhang, X B; Zhao, J; Liu, G F; Cai, H G; Pan, Q M

    2015-08-04

    The highly agile and efficient water-surface locomotion of the water strider has stimulated substantial interest in biomimetic research. In this paper, we propose a new miniature surface tension-driven robot inspired by the water strider. A key feature of this robot is that its actuating leg possesses an ellipse-like spatial trajectory similar to that of a water strider by using a cam-link mechanism. Simplified models are presented to discuss the leg-water interactions as well as critical conditions for a leg penetrating the water surface, and simulations are performed on the robot's dynamic properties. The final fabricated robot weighs about 3.9 g, and can freely and stably walk on water at different gaits. The maximum forward and turning speeds of the robot are measured as 16 cm s(-1) and 23°/s, respectively. Furthermore, a similarity analysis with Bond number and Weber number demonstrates that the locomotion of this robot is quite analogous to that of a real water strider: the surface tension force dominates the lifting force and plays a major role in the propulsion force. This miniature surface tension-driven robot might have potential applications in many areas such as water quality monitoring and aquatic search and rescue.

  12. Tensions between Individual Use and Network Adoption of Social Media Platforms

    DEFF Research Database (Denmark)

    Srinivasan, Nikhil; Damsgaard, Jan

    2013-01-01

    by interviewing individuals within a university context. An analysis of the vignettes and individual use behaviors highlights the tension between network-based adoption of social media platforms and the constraints that the network places on individual use of the platform.......Social media have diffused into the everyday lives of many but still pose challenges to individuals regarding use of these platforms. This paper explores the multiple manners in which social media platforms gets employed by individuals based on an examination of 4 vignettes generated...

  13. A process and device for joining jacket leg chords in an off-shore platform

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, P.A.; Naudin, J.C.

    1995-04-07

    A joining process is presented that allows for the progressive junction, inside the chord, of the weld beads linking the joining parts with the other components of the chord, in order to prevent formation of stress concentration zones that are inconsistent with the high fatigue stresses that undergo off-shore platform jacket legs. The invention concerns also the device for the implementation of the process. 7 figs.

  14. In vivo graft tension in anatomic double-bundle anterior cruciate ligament reconstruction during active leg-raising motion with the knee splinted.

    Science.gov (United States)

    Mae, Tatsuo; Shino, Konsei; Matsumoto, Norinao; Nakata, Ken; Kinugasa, Kazutaka; Yoshikawa, Hideki; Yoneda, Minoru

    2012-04-01

    The purpose of this study was to measure the in vivo graft tension in anatomic 2-bundle anterior cruciate ligament (ACL) reconstruction during active leg-raising exercise with the knee immobilized. Anatomic double-bundle ACL reconstruction was performed with autogenous semitendinosus tendons in 7 patients while under general anesthesia. Two grafts were fixed with 2 EndoButton-CL devices (Smith & Nephew Endoscopy, Andover, MA) on the femur and were temporarily fixed to 2 tension-adjustable force gauges on the anterior tibial cortex. Then, a knee brace in semi-flexion was put around the knee, and 10 N of initial tension was applied to each graft at 20° of flexion. The tension on the anteromedial (AM) and posterolateral (PL) grafts was continuously measured during active leg-raising motion with the knee immobilized after patients had awoken from anesthesia. Then, the tension measurement was repeated during active leg-raising motion with the knee immobilized while a 2-kg weight was fitted around the ankle. In situ graft tension during active leg-raising motion with a knee brace was 10.9 ± 4.0 N for the AM graft and 8.6 ± 5.1 N for the PL graft, whereas the tension with a 2-kg weight around the ankle was 10.9 ± 3.4 N for the AM graft and 9.9 ± 3.6 N for the PL graft. There was no significant difference between each graft in the 2 motions with a paired t test. Graft tension with the knee immobilized with a semi-flexed knee brace during active leg-raising motion was 19.5 N with no weight and 20.8 N with additional weight, both of which were almost equal to the initial graft tension at the time of fixation at 20°. Thus the leg-raising exercise can be recommended as safe when a semi-flexed knee brace is worn after ACL reconstruction. These findings will help to plan postoperative rehabilitation programs with security. Copyright © 2012 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  15. 78 FR 42902 - Safety Zone; Olympus Tension Leg Platform, Mississippi Canyon Block 807, Outer Continental Shelf...

    Science.gov (United States)

    2013-07-18

    ... the purpose of protecting life, property and the marine environment (33 CFR 147.1). Placing a safety... purpose of the proposed rule is to protect life, property and the marine environment. Shell Exploration... will significantly reduce the threat of allisions, oil spills, and releases of natural gas, and thereby...

  16. Vortex-induced vibration of a tension leg platform tendon: multi-mode limit cycle oscillations

    Science.gov (United States)

    Datta, Nabanita

    2017-11-01

    This paper studies the application of mathematical models to analyze the vortex-induced vibrations of the tendons of a given TLP along the Indian coastline, by using an analytical approach, analyzed using MATLAB. The tendon is subjected to a steady current load, which causes vortex-shedding downstream, leading to cross-flow vibrations. The magnitude of the excitation (lift and drag coefficients) depends on the vortex-shedding frequency. The resulting vibration is studied for possible resonant behavior. The excitation force is quantified empirically, the added mass by potential flow hydrodynamics, and the vibration by normal mode summation method. Non-linear viscous damping of the water is considered. The non-linear oscillations are studied by the phase-plane method, investigating the limit-cycle oscillations. The stable/unstable regions of the dynamic behavior are demarcated. The modal contribution to the total deflection is studied to establish the possibility of resonance of one of the wet modes with the vortex-shedding frequency.

  17. Vortex-induced vibration of a tension leg platform tendon: Multi-mode limit cycle oscillations

    Science.gov (United States)

    Datta, Nabanita

    2017-12-01

    This paper studies the application of mathematical models to analyze the vortex-induced vibrations of the tendons of a given TLP along the Indian coastline, by using an analytical approach, analyzed using MATLAB. The tendon is subjected to a steady current load, which causes vortex-shedding downstream, leading to cross-flow vibrations. The magnitude of the excitation (lift and drag coefficients) depends on the vortex-shedding frequency. The resulting vibration is studied for possible resonant behavior. The excitation force is quantified empirically, the added mass by potential flow hydrodynamics, and the vibration by normal mode summation method. Non-linear viscous damping of the water is considered. The non-linear oscillations are studied by the phase-plane method, investigating the limit-cycle oscillations. The stable/unstable regions of the dynamic behavior are demarcated. The modal contribution to the total deflection is studied to establish the possibility of resonance of one of the wet modes with the vortex-shedding frequency.

  18. A joining process for long length sections of offshore platform supporting legs

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, P.A.; Naudin, J.C.

    1995-11-10

    The joining process is aimed for an optimized welding of the rectangular plate and the semi-cylindrical stiffeners that constitute a leg section, in order to enhance the fatigue strength and corrosion resistance of the welds. It involves machining root faces and grooves at the surface of the plate and bevels on the stiffener edges, and the electron beam welding of the stiffener onto the plate; the section is then heat treated. 6 refs., 6 figs.

  19. A joining process for long length sections of offshore platform supporting legs

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, P.A.; Naudin, J.C.

    1995-11-10

    The joining process is aimed for an optimized welding of the rectangular plate and the semi-cylindrical stiffeners that constitute a leg section, in order to enhance the fatigue strength and corrosion resistance of the welds. It involves machining root faces and grooves at the surface of the plate and bevels on the stiffener edges, and the electron beam welding of the stiffener onto the plate; a weld reflow is carried out at the seam root. The section is then heat treated (quenched and tempered). 6 refs., 6 figs.

  20. On a Jansen leg with multiple gait patterns for reconfigurable walking platforms

    Directory of Open Access Journals (Sweden)

    Shunsuke Nansai

    2015-03-01

    Full Text Available Legged robots are able to move across irregular terrains and those based on 1-degree-of-freedom planar linkages can be energy efficient, but are often constrained by a limited range of gaits which can limit their locomotion capabilities considerably. This article reports the design of a novel reconfigurable Theo Jansen linkage that produces a wide variety of gait cycles, opening new possibilities for innovative applications. The suggested mechanism switches from a pin-jointed Grübler kinematic chain to a 5-degree-of-freedom mechanism with slider joints during the reconfiguration process. It is shown that such reconfigurable linkage significantly extend the capabilities of the original design, while maintaining its mechanical simplicity during normal operation, to not only produce different useful gait patterns but also to realize behaviors beyond locomotion. Experiments with an implemented prototype are presented, and their results validate the proposed approach.

  1. Lyden-af-Leg

    DEFF Research Database (Denmark)

    Toft, Herdis

    Præsentation af seniorforsker-projekt Lyden-af-Leg i et traderingsperspektiv og med indledende fokus på YouTube som traderings-platform.......Præsentation af seniorforsker-projekt Lyden-af-Leg i et traderingsperspektiv og med indledende fokus på YouTube som traderings-platform....

  2. Experimental Comparison of Dynamic Responses of a Tension Moored Floating Wind Turbine Platform with and without Spring Dampers

    Science.gov (United States)

    Wright, C.; O'Sullivan, K.; Murphy, J.; Pakrashi, V.

    2015-07-01

    The offshore wind industry is rapidly maturing and is now expanding to more extreme environments in deeper water and farther from shore. To date fixed foundation types (i.e. monopoles, jackets) have been primarily used but become uneconomical in water depths greater than 50m. Floating foundations have more complex dynamics but at the moment no design has reached commercialization, although a number of devices are being tested at prototype stage. The development of concepts is carried out through physical model testing of scaled devices such that to better understand the dynamics of the system and validate numerical models. This paper investigates the testing of a scale model of a tension moored wind turbine at two different scales and in the presence and absence of a spring damper controlling its dynamic response. The models were tested under combined wave and wind thrust loading conditions. The analysis compares the motions of the platform at different scales and structural conditions through RAO, testing a mooring spring damper for load reductions.

  3. Postural balance in low back pain patients: Intra-session reliability of center of pressure on a portable force platform and of the one leg stand test.

    Science.gov (United States)

    Maribo, Thomas; Stengaard-Pedersen, Kristian; Jensen, Lone Donbæk; Andersen, Niels Trolle; Schiøttz-Christensen, Berit

    2011-06-01

    Low back pain (LBP) patients have poorer postural control compared to healthy controls, and the importance of assessing and addressing balance is a matter of debate. In the clinic, balance is often tested by means of the one leg stand test (OLST) while research often employs center of pressure (CoP) on a force platform. Portable force platforms might be of clinical relevance, but their reliability for LBP patients in a clinical setting has not been demonstrated. As LBP patients are more dependent on vision compared to healthy controls, the ratio of tests performed with eyes open and eyes closed (Romberg Ratio) might be of clinical interest. This study aimed to assess postural balance in LBP patients by analyzing intra-session reliability of CoP parameters on a portable force platform, the Romberg Ratio, and the OLST. Furthermore, we aimed to determine whether CoP parameters and OLST measure identical aspects of postural stability. We examined 49 LBP patients and found acceptable reliability of the CoP parameters' trace length and velocity, whereas reliability regarding C90 area, the Romberg Ratio, and the OLST was poor. Correlations between the CoP parameters and OLST were insignificant. Reliability of trace length and velocity is acceptable and can be used as parameters when assessing CoP in LBP patients. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Compliant jacket for offshore drilling and production platform

    Energy Technology Data Exchange (ETDEWEB)

    McGillivray, T.L.; Coull, T.B.

    1986-10-29

    A jacket mounted in water depths in the range of 1000 to 1500 feet or more has a number of spaced, generally parallel legs coupled together by braces. Each leg is tubular and contains a plurality of sleeves and/or guides rigidly secured to the inner surface of the leg. A tubular pile extends downwardly through each respective sleeve into the sea bottom to provide a foundation for the jacket. Each pile thus serves as a compression spring to present tension-compression couples to withstand lateral forces during rocking motion of the jacket. Each pile is adapted to house a well for transfer of resources from the sea bottom to a platform atop the jacket. The legs have bulkheads which define buoyancy chambers for counteracting vertical loads, such as the weight of the platform.

  5. Floating platform for offshore hydrocarbon production

    Energy Technology Data Exchange (ETDEWEB)

    Waddell, J.W.

    1994-07-27

    A floating platform comprises a vessel having a deck or topsides portion mounted above the highest expected water level at the site where the platform is to be located, and a tension moored wellhead/manifold assembly secured to the seabed by at least two tethers against the action of its own buoyancy and floating below the water surface at a predetermined height above the seabed, the arrangement being such that the vessel can be positioned directly over the tension moored wellhead/manifold assembly and can draw oil and/or gas from risers and/or conductors terminating in that assembly for processing and export via the deck or topsides. The vessel may be fixed in position by catenary anchors or tension legs. (Author)

  6. Surface Tension

    Science.gov (United States)

    Theissen, David B.; Man, Kin F.

    1996-01-01

    The effect of surface tension is observed inmany everyday situations. For example, a slowly leaking faucet drips because the force surface tension allows the water to cling to it until a sufficient mass of water is accumulated to break free.

  7. Tension Headache

    Science.gov (United States)

    ... your head Tenderness on your scalp, neck and shoulder muscles Tension headaches are divided into two main categories — ... that monitor and give you feedback on body functions such as muscle tension, heart rate and blood pressure. You then ...

  8. Broken Leg

    Science.gov (United States)

    ... been weakened by a condition such as osteoporosis. Risk factors Stress fractures are often the result of repetitive ... the joint and poor bone alignment can cause osteoarthritis years later. If your leg starts to hurt ...

  9. Skin perfusion pressure measured by isotope washout in legs with arterial occlusive disease. Evaluation of different tracers, comparison to segmental systolic pressure, angiography and transcutaneous oxygen tension and variations during changes in systemic blood pressure

    DEFF Research Database (Denmark)

    Holstein, P; Trap-Jensen, J; Bagger, H

    1983-01-01

    digit (strain gauge technique). The two different methods correlated statistically significant at all four levels, but the systolic blood pressures were higher than the SPP in particular in diabetic legs; (3) Angiograms in 35 legs with AOD showed that the SPP on the ankle was only consistently decreased......The skin perfusion pressure (SPP) measured as the isotope washout cessation external pressure is valuable in selection of major amputation level. Five methodological investigations important to clinical use were carried out: (1) In five normal legs and 10 legs with arterial occlusive disease (AOD......Hg (range 18-98) (P less than 0.02). The average washout constant for the three different tracers were approximately equal and correlated statistically significant with the SPP; (2) In 59 legs with AOD, segmental SPP was compared to segmental systolic blood pressures on the thigh, calf, ankle and first...

  10. Transcutaneous oxygen tension in imminent foot gangrene

    DEFF Research Database (Denmark)

    Tønnesen, K H

    1978-01-01

    Transcutaneous oxygen tension at 44 degree C and maximal isotope clearance (90m Tc-pretechnetate + histramine) just proximal to the 1st toe and systolic toe blood pressure (strain gauge) were studied on a tilt table in patients with various degrees of obstructive arteriosclerotic disease. In legs...... with moderate obstruction, the oxygen tension reached zero at a toe systolic blood pressure of 5--10 mmHg (tilt toe up) and reached arterial oxygen tension at about 50 to 70 mmHg (tilt toe down). In legs withsevere arterial obstruction and ischaemic rest pain, oxygen tension rose from zero not before systolic...... toe blood pressure reached 20--50 mmHg. Significant isotope clearance was seen at pressures below the limits just mentioned for both types of patients. This phenomenon here seen of a perfusion without oxygen supply is explained by a gas leak (rendered significant because of the slow flow rate) from...

  11. Design of a Single Motor Based Leg Structure with the Consideration of Inherent Mechanical Stability

    Science.gov (United States)

    Taha Manzoor, Muhammad; Sohail, Umer; Noor-e-Mustafa; Nizami, Muhammad Hamza Asif; Ayaz, Yasar

    2017-07-01

    The fundamental aspect of designing a legged robot is constructing a leg design that is robust and presents a simple control problem. In this paper, we have successfully designed a robotic leg based on a unique four bar mechanism with only one motor per leg. The leg design parameters used in our platform are extracted from design principles used in biological systems, multiple iterations and previous research findings. These principles guide a robotic leg to have minimal mechanical passive impedance, low leg mass and inertia, a suitable foot trajectory utilizing a practical balance between leg kinematics and robot usage, and the resultant inherent mechanical stability. The designed platform also exhibits the key feature of self-locking. Theoretical tools and software iterations were used to derive these practical features and yield an intuitive sense of the required leg design parameters.

  12. Task driven optimal leg trajectories in insect-scale legged microrobots

    Science.gov (United States)

    Doshi, Neel; Goldberg, Benjamin; Jayaram, Kaushik; Wood, Robert

    Origami inspired layered manufacturing techniques and 3D-printing have enabled the development of highly articulated legged robots at the insect-scale, including the 1.43g Harvard Ambulatory MicroRobot (HAMR). Research on these platforms has expanded its focus from manufacturing aspects to include design optimization and control for application-driven tasks. Consequently, the choice of gait selection, body morphology, leg trajectory, foot design, etc. have become areas of active research. HAMR has two controlled degrees-of-freedom per leg, making it an ideal candidate for exploring leg trajectory. We will discuss our work towards optimizing HAMR's leg trajectories for two different tasks: climbing using electroadhesives and level ground running (5-10 BL/s). These tasks demonstrate the ability of single platform to adapt to vastly different locomotive scenarios: quasi-static climbing with controlled ground contact, and dynamic running with un-controlled ground contact. We will utilize trajectory optimization methods informed by existing models and experimental studies to determine leg trajectories for each task. We also plan to discuss how task specifications and choice of objective function have contributed to the shape of these optimal leg trajectories.

  13. Dynamically Stable Legged Locomotion.

    Science.gov (United States)

    1983-01-27

    balanced itself in 31) using a tabular ctontrol sclwnme. With only thUiee actuated degrees it used a shuffling gait to balance that reminds one of Charlie ... Chaplin . * The present study explores the control of a physical one-legged hopping machine. The objective of using a machine with only one leg was to

  14. Peripheral artery disease - legs

    Science.gov (United States)

    ... the legs, feet, and toes Painful, non-bleeding sores on the feet or toes (most often black) that are slow ... block small arteries Coronary artery disease Impotence Open sores ... (gangrene) The affected leg or foot may need to be amputated

  15. Skin tension related to tension reduction sutures.

    Science.gov (United States)

    Hwang, Kun; Kim, Han Joon; Kim, Kyung Yong; Han, Seung Ho; Hwang, Se Jin

    2015-01-01

    The aim of this study was to compare the skin tension of several fascial/subcutaneous tensile reduction sutures. Six upper limbs and 8 lower limbs of 4 fresh cadavers were used. At the deltoid area (10 cm below the palpable acromion) and lateral thigh (midpoint from the palpable greater trochanter to the lateral border of the patella), and within a 3 × 6-cm fusiform area of skin, subcutaneous tissue defects were created. At the midpoint of the defect, a no. 5 silk suture was passed through the dermis at a 5-mm margin of the defect, and the defect was approximated. The initial tension to approximate the margins was measured using a tensiometer.The tension needed to approximate skin without any tension reduction suture (S) was 6.5 ± 4.6 N (Newton). The tensions needed to approximate superficial fascia (SF) and deep fascia (DF) were 7.8 ± 3.4 N and 10.3 ± 5.1 N, respectively. The tension needed to approximate the skin after approximating the SF was 4.1 ± 3.4 N. The tension needed to approximate the skin after approximating the DF was 4.9 ± 4.0 N. The tension reduction effect of approximating the SF was 38.8 ± 16.4% (2.4 ± 1.5 N, P = 0.000 [ANOVA, Scheffé]). The tension reduction effect of approximating the DF was 25.2% ± 21.9% (1.5 ± 1.4 N, P = 0.001 [ANOVA, Scheffé]). The reason for this is thought to be that the SF is located closely to the skin unlike the DF. The results of this study might be a basis for tension reduction sutures.

  16. Demonstration of Surface Tension.

    Science.gov (United States)

    Rosenthal, Andrew J.

    2001-01-01

    Surface tension is a fundamental obstacle in the spontaneous formation of bubbles, droplets, and crystal nuclei in liquids. Describes a simple overhead projector demonstration that illustrates the power of surface tension that can prevent so many industrial processes. (ASK)

  17. Foot, leg, and ankle swelling

    Science.gov (United States)

    Swelling of the ankles - feet - legs; Ankle swelling; Foot swelling; Leg swelling; Edema - peripheral; Peripheral edema ... Foot, leg, and ankle swelling is common when the person also: Is overweight Has a blood clot ...

  18. Problems with Legs and Feet

    Science.gov (United States)

    ... Your Teeth Heart Murmurs Problems With Legs and Feet KidsHealth > For Kids > Problems With Legs and Feet Print A A A Where would you be without your legs and feet? They do a lot to get you where ...

  19. Quadruped robot control and variable leg transmissions

    OpenAIRE

    Ingvast, Johan

    2006-01-01

    The research presented in this thesis regards walking of quadruped robots, and particularly the walking of the Warp1 robot. The motivation for the robot is to provide a platform for autonomous walking in rough terrain. The thesis contains six papers ranging from development tools to actuation of robot legs. The first paper describes the methods and tools made for control development. These tools feature: programming of the robot without low level coding (C-code); that the controller has to be...

  20. Restless legs syndrome.

    Science.gov (United States)

    Venkateshiah, Saiprakash B; Ioachimescu, Octavian C

    2015-07-01

    Restless legs syndrome is a common sensorimotor disorder characterized by an urge to move, and associated with uncomfortable sensations in the legs (limbs). Restless legs syndrome can lead to sleep-onset or sleep-maintenance insomnia, and occasionally excessive daytime sleepiness, all leading to significant morbidity. Brain iron deficiency and dopaminergic neurotransmission abnormalities play a central role in the pathogenesis of this disorder, along with other nondopaminergic systems, although the exact mechanisms are still. Intensive care unit patients are especially vulnerable to have unmasking or exacerbation of restless legs syndrome because of sleep deprivation, circadian rhythm disturbance, immobilization, iron deficiency, and use of multiple medications that can antagonize dopamine. Published by Elsevier Inc.

  1. Arterial bypass leg - slideshow

    Science.gov (United States)

    ... presentations/100155.htm Arterial bypass leg - series—Normal anatomy To use the sharing features on this page, ... Bethesda, MD 20894 U.S. Department of Health and Human Services National Institutes of Health Page last updated: ...

  2. Leg CT scan

    Science.gov (United States)

    ... stopping.) A computer creates separate images of the body area, called slices. These images can be stored, viewed on a monitor, or printed on film. Three-dimensional (3D) models of the leg can ...

  3. AMRU 3: teleoperated six-legged electrohydraulic robot

    Science.gov (United States)

    Colon, Eric; Polome, Dr.; Piedfort, V.; Baudoin, Yvan

    1995-01-01

    Legged robots represent an alternative to the wheeled or banded platforms and several reasons can justify the development of such architectures. We previously realized two electro- pneumatical robots. We chose to develop an outdoor six-legged electro-hydraulic robot. Our aim was to provide an autonomy of 30 minutes and the capacity to move on terrains with obstacles (maximum 20 cm) and with up- or down-slopes of maximum 30 degree(s). A specific simulation software was used to design the general structure and the legs. The particular design features of the robot lie in a cross-architecture and the inversion of the rear legs. The platform is controlled by a Programmable Logic Controller coupled with the necessary electronic interfaces allowing the teleoperation and the transmission of video signals. Several gaits have been implemented in order to adapt the walk to the environment. Their stability and performances are related.

  4. Protection against high intravascular pressure in giraffe legs.

    Science.gov (United States)

    Petersen, Karin K; Hørlyck, Arne; Ostergaard, Kristine H; Andresen, Joergen; Broegger, Torbjoern; Skovgaard, Nini; Telinius, Niklas; Laher, Ismael; Bertelsen, Mads F; Grøndahl, Carsten; Smerup, Morten; Secher, Niels H; Brøndum, Emil; Hasenkam, John M; Wang, Tobias; Baandrup, Ulrik; Aalkjaer, Christian

    2013-11-01

    The high blood pressure in giraffe leg arteries renders giraffes vulnerable to edema. We investigated in 11 giraffes whether large and small arteries in the legs and the tight fascia protect leg capillaries. Ultrasound imaging of foreleg arteries in anesthetized giraffes and ex vivo examination revealed abrupt thickening of the arterial wall and a reduction of its internal diameter just below the elbow. At and distal to this narrowing, the artery constricted spontaneously and in response to norepinephrine and intravascular pressure recordings revealed a dynamic, viscous pressure drop along the artery. Histology of the isolated median artery confirmed dense sympathetic innervation at the narrowing. Structure and contractility of small arteries from muscular beds in the leg and neck were compared. The arteries from the legs demonstrated an increased media thickness-to-lumen diameter ratio, increased media volume, and increased numbers of smooth muscle cells per segment length and furthermore, they contracted more strongly than arteries from the neck (500 ± 49 vs. 318 ± 43 mmHg; n = 6 legs and neck, respectively). Finally, the transient increase in interstitial fluid pressure following injection of saline was 5.5 ± 1.7 times larger (n = 8) in the leg than in the neck. We conclude that 1) tissue compliance in the legs is low; 2) large arteries of the legs function as resistance arteries; and 3) structural adaptation of small muscle arteries allows them to develop an extraordinary tension. All three findings can contribute to protection of the capillaries in giraffe legs from a high arterial pressure.

  5. Permanent tensions in organization.

    Science.gov (United States)

    Jansson, Noora

    2015-01-01

    The purpose of this paper is to investigate the relationship between permanent tensions and organizational change. This study used paradox theory and a case study. The case organization is a public university hospital in Finland involving several stakeholders. The analysis suggests that the relationship between permanent tensions and organizational change is a paradox that is part of organizational reality. As an organization learns to live with its permanent tensions, the renewal paradox settles into equilibrium. When tensions are provoked, the paradox is disturbed until it finds a new balance. This flexible nature of the paradox is the force that keeps the different stakeholders simultaneously empowered to maintain their unique missions and cohesive in order to benefit from the larger synergy. This research suggests that identification and evaluation of each permanent tension within an organization is important when executing organizational change. The fact that certain tensions are permanent and cannot be solved may have an influence on how planned change initiatives are executed. The results show that permanent tensions may be harnessed for the benefit of an organizational change. This research demonstrates originality by offering an alternative view of tensions, a view which emphasizes not only their permanent and plural nature but their importance for enabling the organization to change at its own, non-disruptive pace. The research also proposes a new concept, the "renewal paradox", to enhance understanding of the relationship between permanent tensions and organizational change.

  6. Electrically evoked and voluntary maximal isometric tension in relation to dynamic muscle performance in elderly male subjects, aged 69 years.

    Science.gov (United States)

    Davies, C T; White, M J; Young, K

    1983-01-01

    The dynamic performance and electrically evoked mechanical properties of elderly triceps surae muscle have been investigated in 9 men, aged 69 yr. Dynamic performance consisted of cycling on a force bicycle and a vertical jump off two feet from a force platform. The results showed that the time to peak tension (TPT) and half relaxation time (1/2 RT) were significantly greater (p less than 0.001) by 30 ms and 22 ms and the supramaximal twitch (Pt) and tetanic (20 Hz-P020) tensions and maximal voluntary contraction (MVC) were less by 45 N (-33%), 708 N (-49%), and 899 N (-43%) in the elderly compared with young male control subjects. On the force platform, the height jumped (Ht), maximal force exerted (P), take-off velocity (VT), net impulse (NI) and peak power output (W) were less by 18.6 cm, 173 N, 0.9 ms-1, 52 Ns and 1120 w respectively. Similar differences of power, force and velocity were observed on the force bicycle. The reduction of W in the elderly was associated with the contractile characteristics of the leg muscle. The loss of contractile speed and capacity to to generate force in old people was reflected in their inability to develop power during the performance of a maximal vertical jump and cycling.

  7. Approach to leg edema

    Directory of Open Access Journals (Sweden)

    Fulvio Pomero

    2017-09-01

    Full Text Available Edema is defined as a palpable swelling caused by an increase in interstitial fluid volume. Leg edema is a common problem with a wide range of possible causes and is the result of an imbalance in the filtration system between the capillary and interstitial spaces. Major causes of edema include venous obstruction, increased capillary permeability and increased plasma volume secondary to sodium and water retention. In both hospital and general practice, the patient with a swollen leg presents a common dilemma in diagnosis and treatment. The cause may be trivial or life-threatening and it is often difficult to determine the clinical pathway. The diagnosis can be narrowed by categorizing the edema according to its duration, distribution (unilateral or bilateral and accompanying symptoms. This work provides clinically oriented recommendations for the management of leg edema in adults.

  8. Leg 179 summary

    Digital Repository Service at National Institute of Oceanography (India)

    Pettigrew, T.J.; Casey, J.F.; Miller, D.J.; Araki, E.; Boissonnas, R.; Busby, R.; Einaudi, F.; Gerdom, M.; Guo, Z.P.; Hopkins, H.; Myers, G.; Rao, D.G.; Shibata, T.; Thy, P.

    Pettigrew, T.L., Casey, J.F., Miller, D.J., et al., 1999 Proceedings of the Ocean Drilling Program, Initial Reports Volume 179 1. LEG 179 SUMMARY 1 Shipboard Scientific Party 2 ABSTRACT Ocean Drilling Program (ODP) Leg 179 set out with two primary objectives... a hole, then simultaneously deepen that hole and stabilize its walls with casing. This system is an adaptation of pneu- matically driven drilling systems that have successfully drilled in envi- ronments not unlike those that present our greatest...

  9. Hemoglobinopathies and Leg Ulcers.

    Science.gov (United States)

    Alavi, Afsaneh; Kirsner, Robert S

    2015-09-01

    Major hemoglobinopathies, including sickle cell anemia, are becoming a global health issue. Leg ulcers are the most common cutaneous manifestation of sickle cell disease and an important contributor to morbidity burden in this population. Leg ulcers following sickling disorders are extremely painful, and hard to heal. The clinical evidence for the optimal management of these ulcers is limited. Treating the cause and the strategies to prevent sickling are the mainstay of treatment. The basic principles of wound bed preparation and compression therapy is beneficial in these patients. © The Author(s) 2015.

  10. Tensions in Distributed Leadership

    Science.gov (United States)

    Ho, Jeanne; Ng, David

    2017-01-01

    Purpose: This article proposes the utility of using activity theory as an analytical lens to examine the theoretical construct of distributed leadership, specifically to illuminate tensions encountered by leaders and how they resolved these tensions. Research Method: The study adopted the naturalistic inquiry approach of a case study of an…

  11. Locking devise for oil platforms

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, P.-A.; Naudin, J.-C.

    1987-10-20

    A self-raising oil well platform comprises a shell mounted to be movable along legs by means of raising mechanisms comprising output gear pinions cooperative with racks mounted on at least a part of the length of the legs. The locking device for such a platform comprises a toothed member forming a counter-rack mounted on the shell of the platform, means for shifting the toothed member transversely of the direction of the rack with which the device is associated for engaging or disengaging the teeth of the toothed member in the teeth of the rack, clamping plates connected to the toothed member and clamping counter-plates connected to the platform, and means for clamping the plates and counter-plates together so as to lock the toothed member in position in the rack. 4 figs.

  12. The mangled lower leg

    NARCIS (Netherlands)

    Hoogendoorn, Jochem Maarten

    2002-01-01

    A surgeon faced with a patient presenting with an open tibial/fibular fracture in combination with severe damage of the surrounding soft tissues, has to make the difficult decision whether to attempt salvage or to perform an immediate amputation of the leg. Until late in the nineteenth century the

  13. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    la Cour, M; Kiilgaard, Jens Folke; Eysteinsson, T

    2000-01-01

    To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide....

  14. ORTHOPEDIC LEG BRACE

    Science.gov (United States)

    Myers, William Neil (Inventor)

    2005-01-01

    Knee braces generally have been rigid in both the knee bending direction and in the knee straightening direction unless a manually operated release is incorporated in them to allow the knee to bend. Desirably a braced knee joint should effectively duplicate the compound, complex, actions of a normal knee. The key to knee braces is the knee joint housing. The housing herein carries a number of cam action pawls. with teeth adapted to engage the internal teeth of a ratchet ring mounted in the housing. Cam action return springs and the shape of the cam action pawl teeth allow rotation of the ratchet ring in a leg straightening direction while still supporting a load. The leg can then be extended during walking while at the same time being prevented by the cam action pawls from buckling in the knee bending direction.

  15. Tension-filled Governance?

    DEFF Research Database (Denmark)

    Celik, Tim Holst

    on the statesituated tension-filled functional relationship between legitimation and accumulation, the study both historically and theoretically reworks this approach and reapplies it for the post-1970s/1990s governance period. It asks whether and to what extent governance has served as a distinctive post- 1970s/1990s...... state-facilitated way of bridging/altering the tension-filled relationship between legitimation and fiscal accumulation in Western European liberal-capitalist democratic polities....

  16. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    la Cour, M; Kiilgaard, Jens Folke; Eysteinsson, T

    2000-01-01

    To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide.......To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide....

  17. Leg size and muscle functions associated with leg compliance

    Science.gov (United States)

    Convertino, Victor A.; Doerr, Donald F.; Flores, Jose F.; Hoffler, G. Wyckliffe; Buchanan, Paul

    1988-01-01

    The relationship between the leg compliance and factors related to the size of leg muscle and to physical fitness was investigated in ten healthy subjects. Vascular compliance of the leg, as determined by a mercury strain gauge, was found to be not significantly correlated with any variables associated with physical fitness per se (e.g., peak O2 uptake, calf strength, age, body weight, or body composition. On the other hand, leg compliance correlated with the calf cross-sectional area (CSA) and the calculated calf volume, with the CSA of calf muscle being the most dominant contributing factor (while fat and bone were poor predicators). It is suggested that leg compliance can be lowered by increasing calf muscle mass, thus providing structural support to limit the expansion of leg veins.

  18. Membrane tension and membrane fusion

    OpenAIRE

    Kozlov, Michael M.; Chernomordik, Leonid V.

    2015-01-01

    Diverse cell biological processes that involve shaping and remodeling of cell membranes are regulated by membrane lateral tension. Here we focus on the role of tension in driving membrane fusion. We discuss the physics of membrane tension, forces that can generate the tension in plasma membrane of a cell, and the hypothesis that tension powers expansion of membrane fusion pores in late stages of cell-to-cell and exocytotic fusion. We propose that fusion pore expansion can require unusually la...

  19. Surface Tension of Spacetime

    Science.gov (United States)

    Perko, Howard

    2017-01-01

    Concepts from physical chemistry and more specifically surface tension are introduced to spacetime. Lagrangian equations of motion for membranes of curved spacetime manifold are derived. The equations of motion in spatial directions are dispersion equations and can be rearranged to Schrodinger's equation where Plank's constant is related to membrane elastic modulus. The equation of motion in the time-direction has two immediately recognizable solutions: electromagnetic waves and corpuscles. The corpuscular membrane solution can assume different genus depending on quantized amounts of surface energy. A metric tensor that relates empty flat spacetime to energetic curved spacetime is found that satisfies general relativity. Application of the surface tension to quantum electrodynamics and implications for quantum chromodynamics are discussed. Although much work remains, it is suggested that spacetime surface tension may provide a classical explanation that combines general relativity with field theories in quantum mechanics and atomic particle physics.

  20. Tension-type headache

    DEFF Research Database (Denmark)

    Bendtsen, Lars; Jensen, Rigmor

    2009-01-01

    The substantial societal and individual burdens associated with tension-type headache (TTH) constitute a previously overlooked major public health issue. TTH is prevalent, affecting up to 78% of the general population, and 3% suffer from chronic TTH. Pericranial myofascial nociception probably...

  1. Social and environmental tensions

    DEFF Research Database (Denmark)

    Saito, Moeko; Rutt, Rebecca Leigh; Chhetri, Bir Bahadur Khanal

    2014-01-01

    to forests. Our case highlights the risk that the mere application of affirmative measures may give rise to difficult social and environmental tensions. Thus, this paper calls for such measures to effectively incorporate local perspectives in their designs and to be reflective, by allowing for regular...

  2. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    Kiilgaard, Jens Folke; Pedersen, D B; Eysteinsson, T

    2004-01-01

    The authors have previously reported that carbonic anhydrase inhibitors such as acetazolamide and dorzolamide raise optic nerve oxygen tension (ONPO(2)) in pigs. The purpose of the present study was to investigate whether timolol, which belongs to another group of glaucoma drugs called beta...

  3. Rein tension during canter

    NARCIS (Netherlands)

    Egenvall, Agneta; Eisersiö, Marie; Rhodin, Marie; van Weeren, P.R.|info:eu-repo/dai/nl/074628550; Roepstorff, Lars

    2015-01-01

    Riders generally use reins as a means for communication with the horse. At present, the signalling pattern is poorly understood. The aim of this study was to illustrate and analyse the rein tension patterns in a number of rider/horse combinations across a variety of exercises in the canter gait. Our

  4. Maneuvers during legged locomotion

    Science.gov (United States)

    Jindrich, Devin L.; Qiao, Mu

    2009-06-01

    Maneuverability is essential for locomotion. For animals in the environment, maneuverability is directly related to survival. For humans, maneuvers such as turning are associated with increased risk for injury, either directly through tissue loading or indirectly through destabilization. Consequently, understanding the mechanics and motor control of maneuverability is a critical part of locomotion research. We briefly review the literature on maneuvering during locomotion with a focus on turning in bipeds. Walking turns can use one of several different strategies. Anticipation can be important to adjust kinematics and dynamics for smooth and stable maneuvers. During running, turns may be substantially constrained by the requirement for body orientation to match movement direction at the end of a turn. A simple mathematical model based on the requirement for rotation to match direction can describe leg forces used by bipeds (humans and ostriches). During running turns, both humans and ostriches control body rotation by generating fore-aft forces. However, whereas humans must generate large braking forces to prevent body over-rotation, ostriches do not. For ostriches, generating the lateral forces necessary to change movement direction results in appropriate body rotation. Although ostriches required smaller braking forces due in part to increased rotational inertia relative to body mass, other movement parameters also played a role. Turning performance resulted from the coordinated behavior of an integrated biomechanical system. Results from preliminary experiments on horizontal-plane stabilization support the hypothesis that controlling body rotation is an important aspect of stable maneuvers. In humans, body orientation relative to movement direction is rapidly stabilized during running turns within the minimum of two steps theoretically required to complete analogous maneuvers. During straight running and cutting turns, humans exhibit spring-mass behavior in the

  5. Surface tension of spherical drops from surface of tension

    Energy Technology Data Exchange (ETDEWEB)

    Homman, A.-A.; Bourasseau, E. [CEA/DAM DIF, F-91297 Arpajon Cedex (France); Stoltz, G. [Université Paris-Est, CERMICS (ENPC), INRIA, F-77455 Marne-la-Vallée (France); Malfreyt, P. [Institut de Chimie de Clermont-Ferrand, Université Blaise Pascal, UMR CNRS 6296, ICCF, BP 10448, F-63000 Clermont-Ferrand (France); Strafella, L.; Ghoufi, A., E-mail: aziz.ghoufi@univ-rennes1.fr [Institut de Physique de Rennes, Université de Rennes 1 UMR 6251 CNRS, 263 avenue Général Leclerc, 35042 Rennes (France)

    2014-01-21

    The determination of surface tension of curved interfaces is a topic that raised many controversies during the last century. Explicit liquid-vapor interface modelling (ELVI) was unable up to now to reproduce interfacial behaviors in drops due to ambiguities in the mechanical definition of the surface tension. In this work, we propose a thermodynamic approach based on the location of surface of tension and its use in the Laplace equation to extract the surface tension of spherical interfaces from ELVI modelling.

  6. Klinefelter Syndrome With Leg Ulcers

    Directory of Open Access Journals (Sweden)

    Narendra G

    1999-01-01

    Full Text Available Leg ulcers are frequently caused by venous insufficiency, arterial insufficiency, neuropathy, or a combination of these factors. Klinefelter syndrome in association with chronic leg ulcers have been reported earlier. We report a case of Klinefelter syndrome with non- healing ulcer. The diagnosis of the Klinefelter syndrome was confirmed by karyotyping.

  7. Surface Tension and Capillary Rise

    Science.gov (United States)

    Walton, Alan J.

    1972-01-01

    Discussion of the shortcomings of textbook explanations of surface tension, distinguishing between concepts of tension and capillary rise. The arguments require only a clear understanding of Newtonian mechanics, notably potential energy. (DF)

  8. Biomechanics of Counterweighted One-Legged Cycling.

    Science.gov (United States)

    Elmer, Steven J; McDaniel, John; Martin, James C

    2016-02-01

    One-legged cycling has served as a valuable research tool and as a training and rehabilitation modality. Biomechanics of one-legged cycling are unnatural because the individual must actively lift the leg during flexion, which can be difficult to coordinate and cause premature fatigue. We compared ankle, knee, and hip biomechanics between two-legged, one-legged, and counterweighted (11.64 kg) one-legged cycling. Ten cyclists performed two-legged (240 W), one-legged (120 W), and counterweighted one-legged (120 W) cycling (80 rpm). Pedal forces and limb kinematics were recorded to determine work during extension and flexion. During counterweighted one-legged cycling relative ankle dorsiflexion, knee flexion, and hip flexion work were less than one-legged but greater than two-legged cycling (all P cycling were greater than one-legged but less than two-legged cycling (all P cycling reduced but did not eliminate differences in joint flexion and extension actions between one- and two-legged cycling. Even with these differences, counterweighted one-legged cycling seemed to have advantages over one-legged cycling. These results, along with previous work highlighting physiological characteristics and training adaptations to counterweighted one-legged cycling, demonstrate that this exercise is a viable alternative to one-legged cycling.

  9. Closed-Loop Tension Control System for Injection Moulding Machine

    African Journals Online (AJOL)

    In any of these processes, the system was to ensure significant tension control in the filament. The design system process began by selection of components with justification. These components were then assembled and tested using Arduino platform with C-programming and finally, conclusion and recommendation were ...

  10. Leg or foot amputation - dressing change

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000018.htm Leg or foot amputation - dressing change To use the sharing features ... chap 14. Read More Compartment syndrome Leg or foot amputation Peripheral artery disease - legs Type 1 diabetes ...

  11. A biologically based neural system coordinates the joints and legs of a tetrapod.

    Science.gov (United States)

    Hunt, Alexander; Schmidt, Manuela; Fischer, Martin; Quinn, Roger

    2015-09-09

    A biologically inspired neural control system has been developed that coordinates a tetrapod trotting gait in the sagittal plane. The developed neuromechanical system is used to explore properties of connections in inter-leg and intra-leg coordination. The neural controller is built with biologically based neurons and synapses, and connections are based on data from literature where available. It is applied to a planar biomechanical model of a rat with 14 joints, each actuated by a pair of antagonistic Hill muscle models. The controller generates tension in the muscles through activation of simulated motoneurons. The hind leg and inter-leg control networks are based on pathways discovered in cat research tuned to the kinematic motions of a rat. The foreleg network was developed by extrapolating analogous pathways from the hind legs. The formulated intra-leg and inter-leg networks properly coordinate the joints and produce motions similar to those of a walking rat. Changing the strength of a single inter-leg connection is sufficient to account for differences in phase timing in different trotting rats.

  12. Platform Constellations

    DEFF Research Database (Denmark)

    Staykova, Kalina Stefanova; Damsgaard, Jan

    2016-01-01

    This research paper presents an initial attempt to introduce and explain the emergence of new phenomenon, which we refer to as platform constellations. Functioning as highly modular systems, the platform constellations are collections of highly connected platforms which co-exist in parallel...

  13. Restless legs syndrome

    Directory of Open Access Journals (Sweden)

    Ovallath S

    2012-10-01

    Full Text Available Sujith Ovallath, P DeepaJames Parkinson's Movement Disorder Research Centre, Kannur Medical College, Kerala, IndiaBackground: Restless legs syndrome (RLS is a common sleep-related disorder characterized by abnormal sensation and an urge to move the lower limbs. Symptoms occur at rest in the evening or at night, and they are alleviated by moving the affected extremity or by walking. Although the exact etiopathogenesis of RLS remains elusive, the rapid improvement of symptoms with dopaminergic agents suggests that dopaminergic system dysfunction may be a basic mechanism. Dopaminergic agents are the best-studied agents, and are considered first-line treatment of RLS.Objective: To review the diagnostic criteria, clinical features, etiopathogenesis, and the treatment options of RLS.Methods: The suggestions are based on evidence from studies published in peer-reviewed journals, or upon a comprehensive review of the medical literature.Results/conclusion: Extensive data are available for proving the link between the dopaminergic system and RLS. A possible genetic link also has been studied extensively. Dopamine agonists, especially pramipexole and ropinirole, are particularly useful in the treatment of RLS. Pharmacological treatment should however be limited to those patients who suffer from clinically relevant RLS with impaired sleep quality or quality of life.Keywords: dopamine, levodopa, pramipexole

  14. Restless legs syndrome: literature review

    Directory of Open Access Journals (Sweden)

    Emmanouil Symvoulakis

    Full Text Available Restless legs syndrome is a distressing condition, with negative effects on sleep and daytime activities that affect personal, family and occupational life. The overall impact of restless legs syndrome on quality of life is comparable to that of chronic and frustrating conditions such as depression and diabetes. Misdiagnosis and inappropriate treatment may increase patients' suffering in terms of uncertainty, overuse or misuse of care services and lack of trust. Presenting a synthesis of the main topics in the literature on restless legs syndrome facilitates for a better understanding and its management in primary care settings.

  15. Measurement of body fat using leg to leg bioimpedance

    OpenAIRE

    Sung, R; Lau, P; Yu, C; Lam, P; Nelson, E

    2001-01-01

    AIMS—(1) To validate a leg to leg bioimpedance analysis (BIA) device in the measurement of body composition in children by assessment of its agreement with dual energy x ray absorptiometry (DXA) and its repeatability. (2) To establish a reference range of percentage body fat in Hong Kong Chinese children.
METHODS—Sequential BIA and DXA methods were used to determine body composition in 49 children aged 7-18 years; agreement between the two methods was calculated. Repea...

  16. Cable tensioned membrane solar collector module with variable tension control

    Science.gov (United States)

    Murphy, Lawrence M.

    1985-01-01

    Disclosed is a solar collector comprising a membrane for concentrating sunlight, a plurality of elongated structural members for suspending the membrane member thereon, and a plurality of control members for adjustably tensioning the membrane member, as well as for controlling a focus produced by the membrane members. Each control member is disposed at a different corresponding one of the plurality of structural members. The collector also comprises an elongated flexible tensioning member, which serves to stretch the membrane member and to thereafter hold it in tension, and a plurality of sleeve members, which serve to provide the membrane member with a desired surface contour during tensioning of the membrane member. The tensioning member is coupled to the structural members such that the tensioning member is adjustably tensioned through the structural members. The tensioning member is also coupled to the membrane member through the sleeve members such that the sleeve members uniformly and symmetrically stretch the membrane member upon applying tension to the tensioning member with the control members.

  17. Restless legs syndrome.

    Science.gov (United States)

    Miletić, Vladimir; Relja, Maja

    2011-12-01

    Being of the most frequent causes of insomnia, which in the end leads to chronic fatigue, inadequate performance of daily activities, and serious disruption of quality of living, restless legs syndrome (RLS) is nowadays not only a serious medical problem but a socio-economical one as well. Prevalence of the disorder in general population is estimated at 5 to 15%. Family history is positive in over 50% of idiopathic RLS patients which points to genetic basis of the disorder. The characteristics of the secondary or acquired form of RLS are symptoms that start later in life as well as a rapid progression of the disease. On the other hand, idiopathic RLS more often starts at a younger age and the prognoses are better. Over twenty disorders and conditions are brought in connection with secondary RLS. Although the cause of primary RLS is still unknown, there is a strong connection between central metabolism of iron as well as dopamine levels and RLS manifestation. A differential diagnosis of RLS includes a wide specter of motor and sensory disorders. Diagnosis is based on clinical features and the history of disease. To correctly diagnose idiopathic RLS one must first eliminate secondary causes of RLS and then also exclude any disorders with clinical features that mimic those of RLS. It has been estimated that some 20 to 25% of patients need pharmacological therapy. Best initial therapy is the application of nonergot dopamine agonists. Anticonvulsants, benzodiazepines and opioides can be given to patients who are refractory to dopaminergic therapy, those suffering from RLS with emphasized painful sensory component and those with RLS connected with insomnia.

  18. Ropinirole in restless leg syndrome.

    Science.gov (United States)

    Ahmed, Iftekhar

    2002-01-01

    Restless leg syndrome (RLS) is a disease of unknown etiology, characterized by paresthesias and an irresistible desire to move the legs. Dopaminergic mechanisms have been implicated in the pathogenesis of this disorder. Dopamine agonists have been used to treat RLS. This paper describes the use of ropinirole, a non-ergoline dopamine agonist, in the treatment of RLS. Polysomnograms after treatment, as well as patient assessment of their symptoms, showed clinical improvement.

  19. Treatment of Restless Legs Syndrome

    OpenAIRE

    Comella, Cynthia L.

    2013-01-01

    Restless legs syndrome (RLS) is a common disorder diagnosed by the clinical characteristics of restlessness in the legs associated often with abnormal sensations that start at rest and are improved by activity, occurring with a diurnal pattern of worsened symptoms at night and improvement in the morning. RLS is the cause of impaired quality of life in those more severely afflicted. Treatment of RLS has undergone considerable change over the last few years. Several classes of medications have ...

  20. Relationship between force fluctuation in the plantar flexor and sustainable time for single-leg standing.

    Science.gov (United States)

    Oshita, Kazushige; Yano, Sumio

    2010-01-01

    The purpose of this study was to investigate the relationships between force fluctuation during isometric plantar flexion and the sustainable time for single-leg standing. Fourteen healthy males (21+/-1 years) performed unilateral (preferred leg) force matching tasks and single-leg quiet standing. Force matching tasks were performed to maintain isometric plantar flexion for 15 s at levels corresponding to 10% and 20% maximal voluntary contraction (MVC) with the visual feedback of force. Force fluctuation during force matching tasks was quantified as the standard deviation of force. Sustainable time for single-leg quiet standing was performed to maintain a single-leg quiet standing barefoot on a platform using the preferred leg with their eyes closed. Force fluctuation was significantly greater in 20% MVC task compared to 10% MVC task. The sustainable time for single-leg quiet standing was strongly correlated with force fluctuation in 20% MVC task (r=-0.56, p=0.04). However, it was not related to force fluctuation in 10% MVC task (r=0.19, p=0.52) or MVC value (r=0.13, p=0.65). These results suggest that a specificity of contraction intensity is observed between force steadiness and the posture stability during single-leg quiet standing; force steadiness during 20% MVC plantar flexion is one of the important components for posture stability during single-leg quiet standing.

  1. Age and sex differences in leg strength in stepping up movements

    Directory of Open Access Journals (Sweden)

    Prusik Katarzyna

    2011-10-01

    Full Text Available The purpose of this study was to test how much aging changes affect the human motor system with respect to relative leg strength. 15 elderly (7 females, 8 males, av. age 67.1 years and 28 young (13 females, 15 males, av. age 22.5 years persons participated in the study. The measurement station consisted of a step-box and four tactile leg sensors. Two of them were placed on a platform on the floor and the other two on a 30.5 cm (12 inches high step-box. Subjects walked up and down irregularly and as quickly as possible on the step-box with the right and the left leg in response to two lights. The leg strength was measured in a series of 20 movements indirectly by the time of straightening the leg put on the step-box. We have found that the speed of stepping up movements (explosive and dynamic strength of leg straightness was higher in the young than elderly subjects for the left and right leg by 21.3 % and 21.8% respectively. Elderly female subjects walked up slower than elderly male subjects only with the left leg by 10.3% and by 24.7% more slowly than young female subjects. Elderly men were slower than young ones by 18.6 %. No statistically significant differences were found in the speed of stepping up movements between young female and male subjects for both legs.

  2. Holding the Tension.

    Science.gov (United States)

    Feudtner, Chris

    2016-05-01

    My colleagues and I had been asked by a member of a clinical team to help sort through the ethics of stopping a life-sustaining intervention for a very ill child. We had already talked with the parents, the physicians, and the folks from nursing, social work, and chaplaincy. Terms like "suffering," "cruel," "compassion," and "moral distress" had been uttered, as had terms like "inappropriate," "unethical," "neglectful," and "risk-management." The group had now stuffed all of these polarizing thoughts and feelings into this cramped room with only one door. And everyone was looking at me. What skill, competency, or inner capacity must one possess to hold and manage such tension? © 2016 The Hastings Center.

  3. Why Do Alcoholic Beverages Have "Legs"?

    Science.gov (United States)

    Silverstein, Todd P.

    1998-06-01

    After a sip of wine, "legs" of liquid typically run up and down the inside of the glass for many minutes. This phenomenon stems from the dipole-dipole intermolecular forces that are so important in understanding the physical behavior of aqueous solutions. The combination of cohesive forces within the liquid and adhesive forces between the liquid and a solid surface can explain physical phenomena such as viscosity, surface tension, capillary action, and the shape of the meniscus. Aqueous ethanol solutions tend to have cohesive forces that are weaker than those of pure water, while their adhesive forces toward polar glass surfaces are roughly equivalent to those of water. Because adhesive forces are stronger than cohesive forces, wine may cling to the glass surface, hovering high above the remainder of the wine in the bottom of the glass. As ethanol evaporates, however, cohesive forces increase until the wine falls in a thin stream. Upon touching the surface of the wine in the bottom of the glass, ethanol concentration is restored, cohesive forces weaken, and the thin stream of wine rises back to the top of the glass.

  4. Complementary Platforms

    NARCIS (Netherlands)

    van Cayseele, P.; Reynaerts, J.

    2007-01-01

    We introduce an analytical framework close to the canonical model of platform competition investigated by Rochet and Tirole (2006) to study pricing decisions in two-sided markets when two or more platforms are needed simultaneously for the successful completion of a transaction. The model developed

  5. Cerveza platforms offer economic options

    Energy Technology Data Exchange (ETDEWEB)

    Leblanc, L.A.

    1982-08-01

    Two single-piece platforms, Cerveze and Cerveza Ligera, were installed by Union Oil Co. in 925-935 ft of water. The technology and equipment used for the two platforms can be used for units to a depth of 1,400 ft in mild climates and to 1,000 ft in more critical weather areas such as the North Sea. The significant improvements in design and procedures in the construction and installation of the Cerveza Ligera platform are: (1) four leg structure, as opposed to eight, requiring less steel; (2) simplified fabrication; and (3) quicker installation. The most significant area of improvement in the Ligera project compared with Cerveza was in communications. Communications between naval architects and onshore launch foremen during loadout, and between surveyors and tug captains during positioning, are cited as examples.

  6. Asymmetrical stabilization and mobilization exploited during static single leg stance and goal directed kicking.

    Science.gov (United States)

    King, Adam C; Wang, Zheng

    2017-08-01

    The motor control properties of the right and left legs are dependent on the stabilization and mobilization features of the motor tasks. The current investigation examined the right and left leg control differences - interlateral asymmetries - during static single leg stance and dynamic goal directed kicking with an emphasis of the asymmetrical stabilization and mobilization components of movements. Ten young, healthy, right-leg preferred individuals with minimal kicking experience completed both tests on each limb. During static single leg stance, participants were requested to stand as still as possible with one leg in contact with a force platform. Interlateral asymmetries of the standing leg were quantified using postural variability measures of the center of pressure (COP) standard deviation in the anterior-posterior (SD-COPAP) and medial-lateral (SD-COPML) directions, resultant COP length and velocity, and 95% COP elliptical area. During dynamic goal directed kicking, participants stood on two adjacent force platforms in a side-by-side foot position and kicked a soccer ball toward three different directions as soon as they received an auditory cue of kicking. Three targets were located -30°, 0° or 30° in front and 3.05 m away from the participants' midline. Participants kicked the ball toward the targets with each of their feet. The vertical ground reaction force (vGRF) of the kicking leg was used to define the preparation (from above two standard deviations of vGRF baseline to toe-off) and swing (from toe-off to toe-return) phases of dynamic kicking. To determine the presence of interlateral asymmetries during dynamic kicking, the magnitude and timing of the anticipatory postural adjustments (APA) during the preparation phase of kicking were quantified using the lateral net COP (COPnet-ML) time series derived from both force platforms. Postural variability measures of the support leg and the kinematic joint range of motion (JROM) trajectories of the

  7. Promethus Hot Leg Piping Concept

    Energy Technology Data Exchange (ETDEWEB)

    AM Girbik; PA Dilorenzo

    2006-01-24

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  8. Leg ulcers due to hyperhomocysteinemia

    Directory of Open Access Journals (Sweden)

    Krupa Shankar D

    2006-01-01

    Full Text Available Chronic leg ulcers are rare in young adults and generally indicate a vascular cause. We report a case of a 26-year-old man with leg ulcers of eight months duration. Doppler study indicated venous incompetence and a postphlebitic limb. However, as the distribution and number of ulcers was not consistent with stasis alone and no features of collagen vascular disease were noted, a hyperviscosity state was considered and confirmed with significantly elevated homocysteine level in the serum. Administration of vitamins B1, B2, B6 and B12, trimethyl-glycine, mecobalamine, folic acid and povidone iodine dressings with culture-directed antibiotic therapy led to a satisfactory healing of ulcers over a period of one month. Hyperhomocysteinemia must be considered in the differential diagnosis of leg ulcers in young individuals.

  9. Surface tension of aqueous humor.

    Science.gov (United States)

    Ross, Andrew; Blake, Robert C; Ayyala, Ramesh S

    2010-09-01

    To measure and compare the surface tension of aqueous humor in patients with and without glaucoma. The surface tension of aqueous humor was measured using a commercially available instrument and software that were validated by using a known fluid (deionized water and methanol). Analysis of aqueous and vitreous samples obtained from 20 rabbit eyes showed that the system could be used successfully for small amounts of ocular fluid. The effect of glaucoma drugs on the surface tension of aqueous humor was then studied in a rabbit model. Comparison of aqueous humor from 66 patients with glaucoma and 53 patients with cataracts but no glaucoma was carried out. The surface tension of rabbit aqueous humor was 65.9 ± 1.2; vitreous, 60.6 ± 2.6; and balanced salt solution, 70.7 ± 0.9. Timolol and latanoprost did not alter the surface tension of the aqueous humor in the rabbit model. The average surface tension of human aqueous humor was 63.33 ± 4.0 (glaucomatous eyes) and 66.19 ± 2.64 (nonglaucomatous eyes with cataracts) (P=0.0001). A technique of measuring the surface tension from small quantities of aqueous humor is validated. Surface tension of the aqueous humor in glaucoma patients was less than that of cataract patients.

  10. Impact of leg lengthening on viscoelastic properties of the deep fascia

    Science.gov (United States)

    Wang, Hai-Qiang; Wei, Yi-Yong; Wu, Zi-Xiang; Luo, Zhuo-Jing

    2009-01-01

    Background Despite the morphological alterations of the deep fascia subjected to leg lengthening have been investigated in cellular and extracellular aspects, the impact of leg lengthening on viscoelastic properties of the deep fascia remains largely unknown. This study aimed to address the changes of viscoelastic properties of the deep fascia during leg lengthening using uniaxial tensile test. Methods Animal model of leg lengthening was established in New Zealand white rabbits. Distraction was initiated at a rate of 1 mm/day and 2 mm/day in two steps, and preceded until increases of 10% and 20% in the initial length of tibia had been achieved. The deep fascia specimens of 30 mm × 10 mm were clamped with the Instron 1122 tensile tester at room temperature with a constant tensile rate of 5 mm/min. After 5 load-download tensile tests had been performed, the specimens were elongated until rupture. The load-displacement curves were automatically generated. Results The normal deep fascia showed typical viscoelastic rule of collagenous tissues. Each experimental group of the deep fascia after leg lengthening kept the properties. The curves of the deep fascia at a rate of 1 mm/day with 20% increase in tibia length were the closest to those of normal deep fascia. The ultimate tension strength and the strain at rupture on average of normal deep fascia were 2.69 N (8.97 mN/mm2) and 14.11%, respectively. The increases in ultimate tension strength and strain at rupture of the deep fascia after leg lengthening were statistically significant. Conclusion The deep fascia subjected to leg lengthening exhibits viscoelastic properties as collagenous tissues without lengthening other than increased strain and strength. Notwithstanding different lengthening schemes result in varied viscoelastic properties changes, the most comparable viscoelastic properties to be demonstrated are under the scheme of a distraction rate of 1 mm/day and 20% increase in tibia length. PMID:19698092

  11. The one-leg standing radiograph

    OpenAIRE

    Pinsornsak, P.; Naratrikun, K.; Kanitnate, S.; Sangkomkamhang, T.

    2016-01-01

    Objectives The purpose of this study was to compare the joint space width between one-leg and both-legs standing radiographs in order to diagnose a primary osteoarthritis of the knee. Methods Digital radiographs of 100 medial osteoarthritic knees in 50 patients were performed. The patients had undergone one-leg standing anteroposterior (AP) views by standing on the affected leg while a both-legs standing AP view was undertaken while standing on both legs. The severity of the osteoarthritis wa...

  12. Peripheral artery bypass - leg - discharge

    Science.gov (United States)

    ... your leg. DO NOT sit for more than 1 hour at a time when you first come home. If you can, ... dressing (bandage) and when you may stop using one. Keep your wound dry. If your incision goes to your groin, keep a dry gauze pad over it to keep it dry. Clean your ...

  13. The Dynamics of Digital Platform Innovation

    DEFF Research Database (Denmark)

    Eaton, Ben

    2016-01-01

    . The dynamic concerning this control of innovation is not well understood in platform literature. This research attempts to address that gap by using qualitative methods to build narrative networks which analyze 45 examples of contested platform innovation. This approach, informed by empirical data sourced......Curated platforms provide an architectural basis for third parties to develop platform complements and for platform owners to control their implementation as a form of open innovation. The refusal to implement complements as innovations can cause tension between platform owners and developers...... from 4664 blogs, identifies patterned sequences of actions describing tussles across the examples. Mechanisms are then identified, which explain how control is asserted and resisted. The principle contribution of this research is to describe and explain the dynamics of contested innovation on curated...

  14. for Fixed Offshore Platforms in Indonesia

    Directory of Open Access Journals (Sweden)

    Tawekal Ricky L.

    2018-01-01

    Full Text Available In RBUI method, platform with higher risk level will need inspection done more intensively than those with lower risk level. However, the probability of failure (PoF evaluation in RBUI method is usually carried out in semi quantitative way by comparing failure parameters associated with the same damage mechanism between a group of platforms located in the same area. Therefore, RBUI will not be effective for platforms spread in distant areas where failure parameter associated with the same damage mechanism may not be the same. The existing standard, American Petroleum Institute, Recommended Practice for Structural Integrity Management of Fixed Offshore Structures (API RP-2SIM, is limited on the general instructions in determining the risk value of a platform, yet it does not provide a detail instruction on how determining the Probability of Failure (PoF of platform. In this paper, the PoF is determined quantitatively by calculating structural reliability index based on structural collapse failure mode, thus the method in determining the inspection schedule is called Risk-Reliability Based Underwater Inspection (RReBUI. Models of 3-legs jacket fixed offshore platform in Java Sea and 4-legs jacket fixed offshore platform in Natuna Sea are used to study the implementation of RReBUI.

  15. Merging Platform Ecosystems in Technology Acquisitions

    DEFF Research Database (Denmark)

    Dowie, Jamie; Henningsson, Stefan; Kude, Thomas

    2017-01-01

    of the merging companies. Given the increasing importance of platforms and value co-creation with third-party providers for companies making technology acquisitions, we complement existing literature by reframing the analysis of technology acquisitions to include the merger of the broader partner ecosystems....... Specifically, we draw on theories of ecosystem governance to analyze how ecosystem tensions unfolded during the ecosystem merger and how the acquirer governed these tensions in SAP SE’s acquisition of the e-commerce provider Hybris AG. Our findings suggest that the governance of ecosystem tensions...... is an important aspect of managing technology acquisitions. We identify the pre-acquisition relation between the acquired company’s ecosystem partners and the acquirer as an important context factor for explaining how a partner company is exposed to the ecosystem tensions during the merger....

  16. Technology Concept of TLP Platform Towing and Installation in Waters with Depth of 60 m

    Directory of Open Access Journals (Sweden)

    Dymarski Czesław

    2017-04-01

    Full Text Available The article is part of the design and research work conducted at the Gdansk University of Technology, Faculty of Ocean Engineering and Ship Technology, in cooperation with a number of other research centres, which concerns offshore wind farms planned to be built in the Polish zone of the Baltic sea in the next years. One of most difficult tasks in this project is building suitable foundations for each power unit consisting of a tower and a wind turbine mounted on its top. Since the water regions selected for building those wind farms have different depths, there was need to study different possible technical variants of this task, with the reference to both the foundation structures themselves, and the technology of their transport and setting, or anchoring. The article presents the technology of towing, from the shipyard to the setting place, and installation of the foundation having the form of a floating platform of TLP (Tension Leg Platform type, anchored by tight chains to suction piles in the waters with depth of 60 m.

  17. Measurement of body fat using leg to leg bioimpedance.

    Science.gov (United States)

    Sung, R Y; Lau, P; Yu, C W; Lam, P K; Nelson, E A

    2001-09-01

    (1) To validate a leg to leg bioimpedance analysis (BIA) device in the measurement of body composition in children by assessment of its agreement with dual energy x ray absorptiometry (DXA) and its repeatability. (2) To establish a reference range of percentage body fat in Hong Kong Chinese children. Sequential BIA and DXA methods were used to determine body composition in 49 children aged 7-18 years; agreement between the two methods was calculated. Repeatability for the BIA method was established from duplicate measurements. Body composition was then determined by BIA in 1139 girls and 1243 boys aged 7-16 years, who were randomly sampled in eight local primary and secondary schools to establish reference ranges. The 95% limits of agreement between BIA and DXA methods were considered acceptable (-3.3 kg to -0.5 kg fat mass and -3.9 to 0.6% body fat). The percentage body fat increased with increasing age. Compared to the 1993 Hong Kong growth survey, these children had higher body mass index. Mean (SD) percentage body fat at 7 years of age was 17.2% (4.4%) and 14.0% (3.4%) respectively for boys and girls, which increased to 19.3% (4.8%) and 27.8% (6.3%) at age 16. Leg to leg BIA is a valid alternative method to DXA for the measurement of body fat. Provisional reference ranges for percentage body fat for Hong Kong Chinese children aged 7-16 years are provided.

  18. The Legs Problem--For All Ages

    Science.gov (United States)

    Way, Jenni

    2005-01-01

    This article presents an example of a versatile multi-solution problem that can be used right across the primary years. The basic problem is: "Noah saw 16 legs go past him into the Ark. How many creatures did he see?" Any even number can be used, although, 2 legs allows only one answer and with 16 legs there are already 14 different…

  19. Managing tension headaches at home

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000421.htm Managing tension headaches at home To use the sharing ... have glasses, use them. Learn and practice stress management. Some people find relaxation exercises or meditation helpful. ...

  20. Tension pneumocephalus: Mount Fuji sign

    Directory of Open Access Journals (Sweden)

    Pulastya Sanyal

    2015-01-01

    Full Text Available A 13-year-old male was operated for a space occupying lesion in the brain. A noncontrast computed tomography scan done in the late postoperative period showed massive subdural air collection causing compression of bilateral frontal lobes with widening of interhemispheric fissure and the frontal lobes acquiring a peak like configuration - causing tension pneumocephalus-"Mount Fuji sign." Tension pneumocephalus occurs when air enters the extradural or intradural spaces in sufficient volume to exert a mass or pressure effect on the brain, leading to brain herniation. Tension pneumocephalus is a surgical emergency, which needs immediate intervention in the form of decompression of the cranial cavity by a burr hole or needle aspiration. The Mount Fuji sign differentiates tension pneumocephalus from pneumocephalus.

  1. Tension pile study : final report.

    Science.gov (United States)

    1970-07-01

    This report contains the results of a short term study of a pile in tension loads. The piles tested were driven on Louisiana Department of Highway's property in response to preceding research work entitled "Stability of Slender Prestressed Concrete P...

  2. A comparison of one-legged and two-legged countermovement jumps

    NARCIS (Netherlands)

    van Soest, A J; Roebroeck, M.E.; Bobbert, M F; Huijing, P A; van Ingen Schenau, G J

    1985-01-01

    Ten well-trained male volleyball players performed one-legged and two-legged vertical countermovement jumps. Ground reaction forces, cinematographic data, and electromyographic data were recorded. Jumping height in one-legged jumps was 58.5% of that reached in two-legged jumps. Mean net torques in

  3. [Restless legs syndrome and nocturnal leg pain : Differential diagnosis and treatment].

    Science.gov (United States)

    Hornyak, M; Stiasny-Kolster, K; Evers, S; Happe, S

    2011-09-01

    Pain in the legs belongs to the five most frequent regional pain symptoms. Restless legs syndrome (RLS) presents a particular differential diagnosis for pain in the legs, which is characterized by a nocturnal urge to move the legs often associated with painful sensations in the legs. It is one of the most common neurological disorders and probably the leading cause of nocturnal pain in the legs. In this overview, the diagnosis and therapy of RLS as well as aspects of pain therapy of the disorder are presented. In addition, the differential diagnoses for exclusion of other specific causes of nocturnal pain in the legs are discussed.

  4. The one-leg standing radiograph

    Science.gov (United States)

    Naratrikun, K.; Kanitnate, S.; Sangkomkamhang, T.

    2016-01-01

    Objectives The purpose of this study was to compare the joint space width between one-leg and both-legs standing radiographs in order to diagnose a primary osteoarthritis of the knee. Methods Digital radiographs of 100 medial osteoarthritic knees in 50 patients were performed. The patients had undergone one-leg standing anteroposterior (AP) views by standing on the affected leg while a both-legs standing AP view was undertaken while standing on both legs. The severity of the osteoarthritis was evaluated using the joint space width and Kellgren-Lawrence (KL) radiographic classification. The t-test was used for statistical analysis. Results The mean medial joint space width found in the one-leg and in the both-legs standing view were measured at 1.8 mm and 2.4 mm, respectively (p leg standing views, respectively. No changes for KL IV osteoarthritis diagnoses have been found between both- and one-leg standing views. Conclusions One-leg standing radiographs better represent joint space width than both-legs standing radiographs. 32% of both-legs standing radiographs have changed the KL grading to a more severe grade than that in the one-leg standing radiographs. Cite this article: P. Pinsornsak, K. Naratrikun, S. Kanitnate, T. Sangkomkamhang. The one-leg standing radiograph: An improved technique to evaluate the severity of knee osteoarthritis. Bone Joint Res 2016;5:436–441. DOI: 10.1302/2046-3758.59.BJR-2016-0049.R1. PMID:27683299

  5. Space platforms

    Science.gov (United States)

    1983-04-01

    The expanded scientific capabilities available by interfacing an orbital, free-flying experiments platform with Shuttle tending are outlined. The platform would be lifted to orbit by the Shuttle, and modularly increased in size on subsequent flights. Science packages could be left on the 26,000 lb space platform for up to six months. Component sections would include electrical and thermal control systems, berthing ports for payloads and an Orbiter, and an attitude control, communications, and data handling subsection. A 12 kW solar array would furnish power, and interconnect with Spacelab would further enhance the operations range. All berthed science packages would have individual pointing ability and grapples for the Orbiter RMS. Eventual evolution to include facilities for a human crew and a 25 kW solar array is projected.

  6. Elastic actuation for legged locomotion

    Science.gov (United States)

    Cao, Chongjing; Conn, Andrew

    2017-04-01

    The inherent elasticity of dielectric elastomer actuators (DEAs) gives this technology great potential in energy efficient locomotion applications. In this work, a modular double cone DEA is developed with reduced manufacturing and maintenance time costs. This actuator can lift 45 g of mass (5 times its own weight) while producing a stroke of 10.4 mm (23.6% its height). The contribution of the elastic energy stored in antagonistic DEA membranes to the mechanical work output is experimentally investigated by adding delay into the DEA driving voltage. Increasing the delay time in actuation voltage and hence reducing the duty cycle is found to increase the amount of elastic energy being recovered but an upper limit is also noticed. The DEA is then applied to a three-segment leg that is able to move up and down by 17.9 mm (9% its initial height), which demonstrates the feasibility of utilizing this DEA design in legged locomotion.

  7. Fibromyxoid sarcoma of the leg

    Directory of Open Access Journals (Sweden)

    Uwe Wollina

    2010-01-01

    Full Text Available A 48-year-old female with an atypical plaque-like lesion of the lower leg is presented in this article. Histologic investigation revealed a rare low-grade fibromyxoid sarcoma (pT1a cN0 cM0; stage Ia of suprafascial localization. Staging of the patient did not reveal metastatic spread. The tumor was surgically removed with wide safety margins. The defect was closed using a mesh graft transplant and vacuum-assisted closure. Healing was complete. Regular follow-up for at least 5 years is recommended. Besides the rareness of this tumor, this case is also remarkable because of the localization on the lower leg and the suprafascial soft tissue.

  8. Født i leg

    DEFF Research Database (Denmark)

    Hoffmeyer, Jesper

    2015-01-01

    Langt snarere end intelligens og rationalitet er det vores uophørlige trang til at lege og til at tale (tænk blot på mobiltelefonenn, der så elegant forbinder begge disse faciliteter), der udgør menneskets kreative særtræk blandt dyrene her på Jorden. Og udviklingen af sprog og leg er indvendigt ...

  9. Platform computing

    CERN Multimedia

    2002-01-01

    "Platform Computing releases first grid-enabled workload management solution for IBM eServer Intel and UNIX high performance computing clusters. This Out-of-the-box solution maximizes the performance and capability of applications on IBM HPC clusters" (1/2 page) .

  10. Payment Platform

    DEFF Research Database (Denmark)

    Hjelholt, Morten; Damsgaard, Jan

    2012-01-01

    Payment transactions through the use of physical coins, bank notes or credit cards have for centuries been the standard formats of exchanging money. Recently online and mobile digital payment platforms has entered the stage as contenders to this position and possibly could penetrate societies...

  11. Note: A thermally stable tension meter for atmospheric soundings using kites.

    Science.gov (United States)

    Walesby, K T; Harrison, R G

    2010-07-01

    Kites offer considerable potential as wind speed sensors--a role distinct from their traditional use as instrument-carrying platforms. In the sensor role, wind speed is measured by kite-line tension. A kite tether line tension meter is described here, using strain gauges mounted on an aluminum ring in a Wheatstone bridge electronic circuit. It exhibits a linear response to tension (19.5 mV N(-1)) with good thermal stability (mean drift of -0.18 N degrees C(-1) over 5-45 degrees C temperature range) and a rapid time response (0.2 s or better). Field comparisons of tether line tension for a Rokkaku kite with a fixed tower sonic anemometer show an approximately linear tension-wind speed relationship over the range 1-6 ms(-1).

  12. Effects of a Novel Neurodynamic Tension Technique on Muscle Extensibility and Stretch Tolerance: A Counterbalanced Cross-Over Study.

    Science.gov (United States)

    Pietrzak, M; Vollaard, N B J

    2016-12-19

    Neurodynamic tension affects hamstring extensibility and stretch tolerance, and is considered important in hamstring injury management. Neurodynamic tension was postulated to affect segmental muscle extensibility and stretch tolerance, and potentially also demonstrate extra-segmental and contralateral effects. Assess the effects of a novel sciatic-tibial neurodynamic tension technique, the modified long sit slump (MLSS), on segmental, extra-segmental and contralateral muscle extensibility and stretch tolerance. Counterbalanced cross-over study. University research laboratory. Thirteen healthy and active subjects (mean ± SD age 24 ± 8y, BMI 23.1 ± 2.8 kg·m-2). MLSS application (5 seconds, 5 repetitions, 3 sets) on two occasions with a three-week washout period,and either stance or skill leg treated in a counterbalanced manner. Segmental and extra-segmental muscle extensibility were measured utilising passive straight leg raise (PSLR) and prone knee bend (PKB) at pre-, immediately post- and one hour post-intervention. Stretch intensity ratings were measured utilising a simple numerical rating scale (SNRS). MLSS significantly increased PSLR and PKB bilaterally (p < 0.001). The effect for PSLR was greater in the ipsilateral leg compared to the contralateral leg (baseline to one hour post: +9 ± 6° and +5 ± 5° respectively, p < 0.001), but not for PKB (baseline to one hour post: ipsilateral leg +5 ± 5°, contralateral leg +5 ± 4°). For both PSLR and PKB the effect of the first session was retained at the start of the second session 3 weeks later. SNRS data were consistent with increased stretch tolerance. Application of a novel sciatic-tibial neurodynamic tension technique, the MLSS, increases muscle extensibility and stretch tolerance segmentally, extra-segmentally and contra-laterally.

  13. Historical Tensions in Engineering Education

    DEFF Research Database (Denmark)

    Jamison, Andrew; Heymann, Matthias

    2012-01-01

    Ever since institutions for educating engineers first began to be ­established in Europe, there have been a number of fundamental tensions as to how that ­educating should best be conducted, what it should consist of, and who should do the educating. These tensions are based on different styles...... or approaches to ­engineering education that have developed historically in different parts of Europe and which have led to what we characterize as “theory-driven,” “practice-driven,” and “technology-driven” approaches. This chapter explores some of the historical roots of these tensions in medieval Europe...... and briefly traces their developmental trajectories through the subsequent formation of institutions of engineering ­education. It has been written as part of PROCEED (Program of Research on Opportunities and Challenges in Engineering Education in Denmark)....

  14. Epilepsy and restless legs syndrome.

    Science.gov (United States)

    Geyer, James D; Geyer, Emery E; Fetterman, Zachary; Carney, Paul R

    2017-03-01

    Restless legs syndrome (RLS) is a common neurological movement disorder occurring in approximately 10% of the general population. The prevalence of moderately severe RLS is 2.7% overall (3.7% for women and 1.7% for men). Epilepsy is also a common neurological disorder with significant associated morbidity and impact on quality of life. We evaluated the severity and frequency of primary RLS in patients with localization-related temporal lobe epilepsy (TLE) and investigated the role of prodromal RLS symptoms as a warning sign and lateralizing indicator. All epilepsy patients seen in the outpatient clinic were screened for movement disorders from 2005 to 2015. Ninety-eight consecutive patients with localization-related TLE (50 right TLE and 48 left TLE) who met inclusion criteria were seen in the outpatient clinic. The control group consisted of 50 individuals with no history or immediate family history of epilepsy. Each patient was evaluated with the International Restless Legs Study Group (IRLSSG) questionnaire, NIH RLS diagnostic criteria, ferritin level, and comprehensive sleep screening including polysomnography. Furthermore, patients with obstructive sleep apnea or a definite cause of secondary restless legs syndrome such as low serum ferritin or serum iron levels were also excluded from the study. There was a significant association between the type of epilepsy and whether or not patients had RLS χ 2 (1)=10.17, pepilepsy than if they had left temporal epilepsy, serving as a potential lateralizing indicator. A prodromal sensation of worsening RLS occurred in some patients providing the opportunity to intervene at an earlier stage in this subgroup. We identified frequent moderate to severe RLS in patients with epilepsy. The frequency of RLS was much more common than would typically be seen in patients of similar age. The restlessness was typically described as moderately severe. The RLS symptoms were more common and somewhat more severe in the right TLE group

  15. The Comparing the Leg Muscles Electromyography during Single Leg Drop Landing in Pesplanus and Normal Men

    Directory of Open Access Journals (Sweden)

    mostafa bazvand

    2016-03-01

    Full Text Available Objective: pesplanus is one of the changes that brings about changes in muscle activation patterns. Being aware of muscles activity changes in various standing positions among pesplanus patients provides insights into preventing lower extremity injuries in this population. The aim of this study was to compare leg muscles electromyography during various standing positions in pesplanus and normal subjects. Methods: 60 healthy male university students, 30 subjects with pesplanus deformity (with average age 23/54±3/57 year, average height 175/34±7/62 cm, average weight 74/87±10/72 kg and 30 normal subjects (with average age 22/97±2/38 year, average height 176/6±5/59 cm, average weight 73/58±8/36 kg participated in this comparative study. Deformity of pesplanus was assessed with navicular drop test. Each subject performed single-leg landing dropping from 30cm height onto a force platform where muscles activity was recorded with EMG device. For data analysis, Matlab and Spss softwares were used and independent sample t-test was used to compare the dependent variables at a significance level of P &le 0/05. Results: Significant differences were observed between the two groups for the activities of the longus peroneus and anterior tibialis muscles ( p&le0/05 while no significant differences were observed in other muscles. Conclusion: The changes in the normal structure of the foot might affect muscle activities during standing, which can cause changes in the injury patterns. Therefore, it is proposed that focusing on corrective exercises and therapy plan can reduce these risks.

  16. Treatment of restless legs syndrome.

    Science.gov (United States)

    Comella, Cynthia L

    2014-01-01

    Restless legs syndrome (RLS) is a common disorder diagnosed by the clinical characteristics of restlessness in the legs associated often with abnormal sensations that start at rest and are improved by activity, occurring with a diurnal pattern of worsened symptoms at night and improvement in the morning. RLS is the cause of impaired quality of life in those more severely afflicted. Treatment of RLS has undergone considerable change over the last few years. Several classes of medications have demonstrated efficacy, including the dopaminergic agents and the alpha-2-delta ligands. Levodopa was the first dopaminergic agent found to be successful. However, chronic use of levodopa is frequently associated with augmentation that is defined as an earlier occurrence of symptoms frequently associated with worsening severity and sometimes spread to other body areas. The direct dopamine agonists, including ropinirole, pramipexole, and rotigotine patch, are also effective, although side effects, including daytime sleepiness, impulse control disorders, and augmentation, may limit usefulness. The alpha-2-delta ligands, including gabapentin, gabapentin enacarbil, and pregabalin, are effective for RLS without known occurrence of augmentation or impulse control disorders, although sedation and dizziness can occur. Other agents, including the opioids and clonazepam do not have sufficient evidence to recommend them as treatment for RLS, although in an individual patient, they may provide benefit.

  17. Restless Legs Syndrome -- Causes and Symptoms

    Science.gov (United States)

    ... Diagnosis Treatment Jet Lag Overview Symptoms & Self Test Treatment Narcolepsy Overview & Facts Symptoms Self-Tests & Diagnosis Treatment Restless Legs Syndrome Overview & Facts Causes & Symptoms Self- ...

  18. Tension type headaches: a review

    African Journals Online (AJOL)

    Acetaminophen (paracetamol) 500-1 000 mg and aspirin 500-. 1 000 mg, have been demonstrated to be an effective first-line treatment for episodic tension-type headaches in most placebo- controlled trials. 23,24 Fast absorptive formulations of the latter are preferred for rapidity of action.25 It is worth noting that these.

  19. Abolishing the maximum tension principle

    Directory of Open Access Journals (Sweden)

    Mariusz P. Da̧browski

    2015-09-01

    Full Text Available We find the series of example theories for which the relativistic limit of maximum tension Fmax=c4/4G represented by the entropic force can be abolished. Among them the varying constants theories, some generalized entropy models applied both for cosmological and black hole horizons as well as some generalized uncertainty principle models.

  20. Headache (chronic tension-type).

    Science.gov (United States)

    Krishnan, Anita; Silver, Nicholas

    2009-07-22

    Chronic tension-type headache (CTTH) is a disorder that evolves from episodic tension-type headache, with daily or very frequent episodes of headache lasting minutes to days. It affects 4.1% of the general population in the USA, and is more prevalent in women (up to 65% of cases). We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of drug treatments for chronic tension-type headache? What are the effects of non-drug treatments for chronic tension-type headache? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2007 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). We found 50 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. In this systematic review, we present information relating to the effectiveness and safety of the following interventions: acupuncture; amitriptyline; analgesics; anticonvulsant drugs; benzodiazepines; botulinum toxin; chiropractic and osteopathic manipulations; cognitive behavioural therapy (CBT); Indian head massage; mirtazapine; relaxation and electromyographic biofeedback; selective serotonin reuptake inhibitor antidepressants (SSRIs); and tricyclic antidepressants (other than amitriptyline).

  1. CALCULATION OF TENSION FORCE OF BELT CONVEYOR

    OpenAIRE

    Ismet Ibishi; Ahmet Latifi; Gzim Ibishi; Kadri Sejdiu; Melihate Shala-Galica; Bekim Latifi

    2012-01-01

    In this paper is done the explanation on tension fashion of the belt conveyor which is employed in Kosovo Energy Corporation – KEK, for coal transportation to provide electric power plant. The aim of the paper enables to recognize tension forces not to pass with deformation of belt so that this problem will damage the workingprocess. Work principle is based on initial tension and tension during working process. The fact is known that the tension starts from the carriage on the way to tension ...

  2. Postural control of typical developing boys during the transition from double-leg stance to single-leg stance.

    Science.gov (United States)

    Deschamps, Kevin; Staes, Filip; Peerlinck, Kathelijne; Van Geet, Kristel; Hermans, Cedric; Lobet, Sebastien

    2017-02-01

    Literature is lacking information about postural control performance of typically developing children during a transition task from double-leg stance to single-leg stance. The purpose of the present study was therefore to evaluate the clinical feasibility of a transition task in typical developing age groups as well as to study the correlation between associated balance measures and age.Thirty-three typically developing boys aged 6-20 years performed a standard transition task from DLS to SLS with eyes open (EO) and eyes closed (EC). Balance features derived from the center of pressure displacement captured by a single force platform were correlated with age on the one hand and considered for differences in the perspective of limb dominance on the other hand.All TDB (typically developing boys) were able to perform the transition task with EO. With respect to EC condition, all TDB from the age group 6-7 years and the youngest of the age group 8-12 years (N = 4) were unable to perform the task. No significant differences were observed between the balance measures of the dominant and non-dominant limbs.With respect to EO condition, correlation analyses indicated that time to new stability point (TNSP) as well as the sway measure after this TNSP were correlated with age (p postural balance of typically developing children during walking, running, sit-to-stand, and bipodal and unipodal stance has been well documented in the literature. • These reference data provided not only insight into the maturation process of the postural control system, but also served in diagnosing and managing functional repercussions of neurological and orthopedic pathologies. What is New: • Objective data regarding postural balance of typical developing children during a transition task from double-leg stance to single-leg stance. • Insight into the role of maturation on the postural control system.

  3. Core vs. Bulk Samples in Soil-Moisture Tension Analyses

    Science.gov (United States)

    Walter M. Broadfoot

    1954-01-01

    The usual laboratory procedure in determining soil-moisture tension values is to use "undisturbed" soil cores for tensions up to 60 cm. of water and bulk soil samples for higher tensions. Low tensions are usually obtained with a tension table and the higher tensions by use of pressure plate apparatus. In tension analysis at the Vicksburg Infiltration Project...

  4. The Relationship among Leg Strength, Leg Power and Alpine Skiing Success.

    Science.gov (United States)

    Gettman, Larry R.; Huckel, Jack R.

    The purpose of this study was to relate leg strength and power to alpine skiing success as measured by FIS points. Isometric leg strength was represented by the knee extension test described by Clarke. Leg power was measured by the vertical jump test and the Margaria-Kalamen stair run. Results in the strength and power tests were correlated with…

  5. A highly adaptive magnetorheological fluid robotic leg for efficient terrestrial locomotion

    Science.gov (United States)

    Jiang, Nan; Sun, Shuaishuai; Ouyang, Yiming; Xu, Min; Li, Weihua; Zhang, Shiwu

    2016-09-01

    To survive in nature, animals adjust the characteristics of their legs or fins to adapt the motion to their environment. Inspired by the locomotion of animals, a study on the tunable stiffness and damping of a leg will help in the development of intelligent locomotion robots. In this paper we report on the development and experiment of a novel and simple robotic leg that can be adapted to the environment via a smart magnetorheological fluid (MRF). The robotic leg consists of a rotation MRF damper, a torsional spring, a ‘foot’ and a ‘leg’. The curved part of the ‘foot’ makes contact with the grounds while the other end is linked to an outer cylinder of the MRF damper with an inelastic cable. The variable force arm rising from the MRF damper and the torsional spring can help the leg adapt to a changing environment. The characteristics of the MRF damper have been investigated and a model is built to describe its mechanical features when different currents are applied to the MRF damper. A test on a linear dynamic test instrument has been conducted to verify the accuracy of the model. The robotic leg is installed in a locomotion platform to investigate the speed of its locomotion and the cost of the transport; the result demonstrated the feasibility and adaptability of the leg when walking on hard terrain. Its simple structure, high adaptability, and easy control of the MRF leg helped in the design and development of a high performance field robot that can adapt to various environments.

  6. Leg ischemia post-varicocelectomy

    Directory of Open Access Journals (Sweden)

    Al-Wahbi AM

    2016-03-01

    Full Text Available Abdullah M Al-Wahbi1, Shaza Elmoukaied2 1Division of Vascular Surgery, Department of Surgery, King Abdulaziz Medical City, Riyadh, Saudi Arabia; 2Department of Surgery, Dr Sulaiman Al Habib Hospital, Riyadh, Saudi Arabia Abstract: Varicocelectomy is the most commonly performed operation for the treatment of male infertility. Many surgical approaches are used as each of them has advantages over the other and is preferred by surgeons. Vascular injury has never been reported as a complication of varicocelectomy apart from testicular artery injury. We present a 36-year-old male who developed leg ischemia post-varicocelectomy due to common femoral artery injury. He was successfully treated by using a vein graft. Keywords: varicocele, varicocelectomy, complications, vascular injuries

  7. Actin cortex architecture regulates cell surface tension.

    Science.gov (United States)

    Chugh, Priyamvada; Clark, Andrew G; Smith, Matthew B; Cassani, Davide A D; Dierkes, Kai; Ragab, Anan; Roux, Philippe P; Charras, Guillaume; Salbreux, Guillaume; Paluch, Ewa K

    2017-06-01

    Animal cell shape is largely determined by the cortex, a thin actin network underlying the plasma membrane in which myosin-driven stresses generate contractile tension. Tension gradients result in local contractions and drive cell deformations. Previous cortical tension regulation studies have focused on myosin motors. Here, we show that cortical actin network architecture is equally important. First, we observe that actin cortex thickness and tension are inversely correlated during cell-cycle progression. We then show that the actin filament length regulators CFL1, CAPZB and DIAPH1 regulate mitotic cortex thickness and find that both increasing and decreasing thickness decreases tension in mitosis. This suggests that the mitotic cortex is poised close to a tension maximum. Finally, using a computational model, we identify a physical mechanism by which maximum tension is achieved at intermediate actin filament lengths. Our results indicate that actin network architecture, alongside myosin activity, is key to cell surface tension regulation.

  8. Light Scattering by Surface Tension Waves.

    Science.gov (United States)

    Weisbuch, G.; Garbay, F.

    1979-01-01

    This simple and inexpensive experiment is an illustration of the physical concepts of interaction between light and surface tension waves, and provides a new method of measuring surface tension. (Author/GA)

  9. SURFACE TENSION TECHNIQUES FOR MOLTEN SALTS

    Science.gov (United States)

    Some 200 surface tension determinations were made on 107 single-salt melts using eight experimental techniques. From a consideration of the... surface tension range of applicability and temperature limitation for these techniques are briefly considered.

  10. A TOGgle for Tension at Kinetochores

    OpenAIRE

    Cheerambathur, Dhanya K.; Prevo, Bram; Desai, Arshad

    2016-01-01

    Differential stability of kinetochore-microtubule attachments at low versus high tension is critical for accurate chromosome segregation. Miller et al. find that a TOG domain microtubule-binding protein imparts intrinsic tension selectivity to kinetochore-microtubule attachments.

  11. Intensive treatment of leg lymphedema

    Directory of Open Access Journals (Sweden)

    Pereira de Godoy Jose

    2010-01-01

    Full Text Available Background: Despite of all the problems caused by lymphedema, this disease continues to affect millions of people worldwide. Thus, the identification of the most efficacious forms of treatment is necessary. Aim: The aim of this study was to evaluate a novel intensive outpatient treatment for leg lymphedema. Methods: Twenty-three legs of 19 patients were evaluated in a prospective randomized study. The inclusion criteria were patients with Grade II and III lymphedema, where the difference, measured by volumetry, between the affected limb below the knee and the healthy limb was greater than 1.5 kg. Intensive treatment was carried out for 6- to 8-h sessions in the outpatient clinic. Analysis of variance was utilized for statistical analysis with an alpha error of 5% (P-value < 0.05 being considered significant. Results: All limbs had significant reductions in size with the final mean loss being 81.1% of the volume of edema. The greatest losses occurred in the first week (P-value < 0.001. Losses of more than 90% of the lymphedema occurred in 9 (39.13% patients; losses of more than 80% in 13 (56.52%, losses of more than 70% in 17 (73.91% and losses of more than 50% were recorded for 95.65% of the patients; only 1 patient lost less than 50% (37.9% of the edema. Conclusion: The intensive treatment of lymphedema in the outpatient clinic can produce significant reductions in the volume of edema over a short period of time and can be recommended for any grade of lymphedema, in particular the more advanced degrees.

  12. Compression for venous leg ulcers.

    Science.gov (United States)

    O'Meara, Susan; Cullum, Nicky A; Nelson, E Andrea

    2009-01-21

    Around one percent of people in industrialised countries will suffer from a leg ulcer at some time. The majority of these leg ulcers are due to problems in the veins, resulting in an accumulation of blood in the legs. Leg ulcers arising from venous problems are called venous (varicose or stasis) ulcers. The main treatment has been a firm compression garment (bandage or stocking) in order to aid venous return. There is a large number of compression garments available and it is unclear whether they are effective in treating venous ulcers and which compression garment is the most effective. To undertake a systematic review of all randomised controlled trials of the clinical effectiveness of compression bandage or stocking systems in the treatment of venous leg ulceration.Specific questions addressed by the review are:1. Does the application of compression bandages or stockings aid venous ulcer healing? 2. Which compression bandage or stocking system is the most effective? For this update we searched the Cochrane Wounds Group Specialised Register (14/10/08); The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4 2008); Ovid MEDLINE (1950 to October Week 1 2008); Ovid EMBASE (1980 to 2008 Week 41) and Ovid CINAHL (1982 to October Week 1 2008). No date or language restrictions were applied. Randomised controlled trials recruiting people with venous leg ulceration that evaluated any type of compression bandage system or compression hosiery were eligible for inclusion. Comparators included no compression (e.g. primary dressing alone, non-compressive bandage) or an alternative type of compression. Trials had to report an objective measure of ulcer healing in order to be included (primary outcome for the review). Secondary outcomes of the review included ulcer recurrence, costs, quality of life, pain, adverse events and withdrawals. There was no restriction on date, language or publication status of trials. Details of eligible studies were

  13. X-Ray Exam: Femur (Upper Leg)

    Science.gov (United States)

    ... leg, and an image is recorded on special film or a computer. This image shows the soft tissues and the bone in the upper leg, which is called the femur. The X-ray image is black and white. Dense body parts that block the passage of the X- ...

  14. Static balance according to hip joint angle of unsupported leg during one-leg standing

    OpenAIRE

    Cha, Ju-Hyung; Kim, Jang-Joon; Ye, Jae-Gwan; Lee, Seul-Ji; Hong, Jeong-Mi; Choi, Hyun-Kyu; Choi, Ho-Suk; Shin, Won-Seob

    2017-01-01

    [Purpose] This study aimed to determine static balance according to hip joint angle of the unsupported leg during one-leg standing. [Subjects and Methods] Subjects included 45 healthy adult males and females in their 20s. During one-leg standing on the non-dominant leg, the position of the unsupported leg was classified according to hip joint angles of point angle was class. Static balance was then measured using a force plate with eyes open and closed. The total length, sway velocity, maximu...

  15. Intraoperative Development of Tension Pneumocephalus in a ...

    African Journals Online (AJOL)

    Included is a literature review of studies discussing the role of N2O in the development of tension pneumocephalus. N2O is associated with tension pneumocephalus especially in the setting of preexisting pneumocephalus. Tension pneumocephalus can manifest as Cushing response and immediate decompression is ...

  16. The Plastic Tension Field Method

    DEFF Research Database (Denmark)

    Hansen, Thomas

    2005-01-01

    . The emphasis is attached to the presentation of a design method based on the diagonal tension field theory. Also, how to determine the load-carrying capacity of a given steel plate girder with transverse web stiffeners, is briefly presented. The load-carrying capacity may be predicted by applying both......This paper describes a calculation method for steel plate girders with transverse web stiffeners subjected to shear. It may be used for predicting the failure load or, as a design method, to determine the optimal amount of internal web stiffeners. The new method is called the plastic tension field...... method. The method is based on the theory of plasticity and is analogous to the so-called diagonal compression field method developed for reinforced concrete beams with transverse stirrups, which is adopted in the common European concrete code (Eurocode 2). Many other theories have been developed...

  17. Robust Tensioned Kevlar Suspension Design

    Science.gov (United States)

    Young, Joseph B.; Naylor, Bret J.; Holmes, Warren A.

    2012-01-01

    One common but challenging problem in cryogenic engineering is to produce a mount that has excellent thermal isolation but is also rigid. Such mounts can be achieved by suspending the load from a network of fibers or strings held in tension. Kevlar fibers are often used for this purpose owing to their high strength and low thermal conductivity. A suite of compact design elements has been developed to improve the reliability of suspension systems made of Kevlar.

  18. Doppler ultrasound exam of an arm or leg

    Science.gov (United States)

    ... related deaths are caused by cardiovascular problems, not lung cancer. Alternative Names Peripheral vascular disease - Doppler; PVD - Doppler; PAD - Doppler; Blockage of leg arteries - Doppler; Intermittent claudication - Doppler; Arterial insufficiency of the legs - Doppler; Leg pain and cramping - ...

  19. Steerable Hopping Six-Legged Robot

    Science.gov (United States)

    Younse, Paulo; Aghazarian, Hrand

    2010-01-01

    The figure depicts selected aspects of a six-legged robot that moves by hopping and that can be steered in the sense that it can be launched into a hop in a controllable direction. This is a prototype of hopping robots being developed for use in scientific exploration of rough terrain on remote planets that have surface gravitation less than that of Earth. Hopping robots could also be used on Earth, albeit at diminished hopping distances associated with the greater Earth gravitation. The upper end of each leg is connected through two universal joints to an upper and a lower hexagonal frame, such that the tilt of the leg depends on the relative position of the two frames. Two non-back-driveable worm-gear motor drives are used to control the relative position of the two frames along two axes 120 apart, thereby controlling the common tilt of all six legs and thereby, further, controlling the direction of hopping. Each leg includes an upper and a lower aluminum frame segment with a joint between them. A fiberglass spring, connected via hinges to both segments, is used to store hopping energy prior to launch into a hop and to cushion the landing at the end of the hop. A cable for loading the spring is run into each leg through the center of the universal joints and then down along the center lines of the segments to the lower end of the leg. A central spool actuated by a motor with a harmonic drive and an electromagnetic clutch winds in all six cables to compress all six springs (thereby also flexing all six legs) simultaneously. To ensure that all the legs push off and land in the same direction, timing- belt pulley drives are attached to the leg segments, restricting the flexing and extension of all six legs to a common linear motion. In preparation for a hop, the spool can be driven to load the spring legs by an amount corresponding to a desired hop distance within range. The amount of compression can be computed from the reading of a shaft-angle encoder that

  20. Dynamic response mitigation of floating wind turbine platforms using tuned liquid column dampers.

    Science.gov (United States)

    Jaksic, V; Wright, C S; Murphy, J; Afeef, C; Ali, S F; Mandic, D P; Pakrashi, V

    2015-02-28

    In this paper, we experimentally study and compare the effects of three combinations of multiple tuned liquid column dampers (MTLCDs) on the dynamic performance of a model floating tension-leg platform (TLP) structure in a wave basin. The structural stability and safety of the floating structure during operation and maintenance is of concern for the performance of a renewable energy device that it might be supporting. The dynamic responses of the structure should thus be limited for these renewable energy devices to perform as intended. This issue is particularly important during the operation of a TLP in extreme weather conditions. Tuned liquid column dampers (TLCDs) can use the power of sloshing water to reduce surge motions of a floating TLP exposed to wind and waves. This paper demonstrates the potential of MTLCDs in reducing dynamic responses of a scaled TLP model through an experimental study. The potential of using output-only statistical markers for monitoring changes in structural conditions is also investigated through the application of a delay vector variance (DVV) marker for different conditions of control for the experiments. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  1. Small membranes under negative surface tension.

    Science.gov (United States)

    Avital, Yotam Y; Farago, Oded

    2015-03-28

    We use computer simulations and a simple free energy model to study the response of a bilayer membrane to the application of a negative (compressive) mechanical tension. Such a tension destabilizes the long wavelength undulation modes of giant vesicles, but it can be sustained when small membranes and vesicles are considered. Our negative tension simulation results reveal two regimes-(i) a weak negative tension regime characterized by stretching-dominated elasticity and (ii) a strong negative tension regime featuring bending-dominated elastic behavior. This resembles the findings of the classic Evans and Rawicz micropipette aspiration experiment in giant unilamellar vesicles (GUVs) [E. Evans and W. Rawicz, Phys, Rev. Lett. 64, 2094 (1990)]. However, in GUVs the crossover between the two elasticity regimes occurs at a small positive surface tension, while in smaller membranes it takes place at a moderate negative tension. Another interesting observation concerning the response of a small membrane to negative surface tension is related to the relationship between the mechanical and fluctuation tensions, which are equal to each other for non-negative values. When the tension decreases to negative values, the fluctuation tension γ drops somewhat faster than the mechanical tension τ in the small negative tension regime, before it saturates (and becomes larger than τ) for large negative tensions. The bending modulus exhibits an "opposite" trend. It remains almost unchanged in the stretching-dominated elastic regime, and decreases in the bending-dominated regime. Both the amplitudes of the thermal height undulations and the projected area variations diverge at the onset of mechanical instability.

  2. Hot Leg Piping Materials Issues

    Energy Technology Data Exchange (ETDEWEB)

    V. Munne

    2006-07-19

    With Naval Reactors (NR) approval of the Naval Reactors Prime Contractor Team (NRPCT) recommendation to develop a gas cooled reactor directly coupled to a Brayton power conversion system as the space nuclear power plant (SNPP) for Project Prometheus (References a and b) the reactor outlet piping was recognized to require a design that utilizes internal insulation (Reference c). The initial pipe design suggested ceramic fiber blanket as the insulation material based on requirements associated with service temperature capability within the expected range, very low thermal conductivity, and low density. Nevertheless, it was not considered to be well suited for internal insulation use because its very high surface area and proclivity for holding adsorbed gases, especially water, would make outgassing a source of contaminant gases in the He-Xe working fluid. Additionally, ceramic fiber blanket insulating materials become very friable after relatively short service periods at working temperatures and small pieces of fiber could be dislodged and contaminate the system. Consequently, alternative insulation materials were sought that would have comparable thermal properties and density but superior structural integrity and greatly reduced outgassing. This letter provides technical information regarding insulation and materials issues for the Hot Leg Piping preconceptual design developed for the Project Prometheus space nuclear power plant (SNPP).

  3. Benzodiazepines for restless legs syndrome.

    Science.gov (United States)

    Carlos, Karla; Prado, Gilmar F; Teixeira, Camila Dm; Conti, Cristiane; de Oliveira, Marcio M; Prado, Lucila Bf; Carvalho, Luciane Bc

    2017-03-20

    Restless legs syndrome (RLS) is a common disease affecting about 5% to 15% of the population. Symptoms of RLS can be severe in a minority of and can have a major impact on sleep, mostly sleep initiation, and quality of life. Benzodiazepines are drugs that can induce and maintain sleep and, hence, intuitively are thought to be beneficial to people with RLS. Altough benzodiazepines, particularly clonazepam, are used to treat RLS symptoms, a systematic review done by the American Academy of Sleep Medicine stated that benzodiazepines should not be used as a first-line treatment, although could be used as a coadjuvant therapy. To evaluate the efficacy and safety of benzodiazepine compared to placebo or other treatment for idiopathic RLS, including unconfounded trials comparing benzodiazepines versus open control. In March 2016 we searched CENTRAL, MEDLINE, Embase and LILACS We checked the references of each study and contacted study authors to identify any additional studies. We considered studies published in any language. Randomised clinical trials of benzodiazepine treatment in idiopathic RLS. We did not perform data collection and analysis, since we did not include any studies, MAIN RESULTS: We did not identify any studies that met the inclusion criteria of the review. Two cross-over studies are awaiting classification because the cross-over trials did not give data at the end of the first cross-over period. The effectiveness of benzodiazepines for RLS treatment is currently unknown.

  4. Pramipexole: in restless legs syndrome.

    Science.gov (United States)

    McCormack, Paul L; Siddiqui, M Asif A

    2007-01-01

    Pramipexole is an oral, non-ergoline dopamine agonist with selectivity for the dopamine D(3) receptor, which was recently approved in the EU and the US for the treatment of idiopathic restless legs syndrome (RLS) in adults. In a polysomnographic study, pramipexole 0.125, 0.25, 0.50 or 0.75 mg once daily for 3 weeks significantly reduced from baseline the periodic limb movement index compared with placebo (-27 to -53 vs -3). Pramipexole at a median dosage of 0.35 mg/day for 6 weeks significantly reduced from baseline the mean International RLS Study Group rating scale (IRLS) score compared with placebo (-12.4 vs -6.1) and produced a significantly higher response ('much improved' or 'very much improved') rate (63% vs 33%) according to the Clinical Global Impressions-Improvement (CGI-I) scale. In a controlled-withdrawal study in which responders to pramipexole following 6 months' therapy were randomised to pramipexole or placebo for 12 weeks, significantly less pramipexole than placebo recipients reached the target event of predefined worsening of symptoms (21% vs 86%). Treatment with pramipexole 0.25, 0.50 or 0.75 mg once daily for 12 weeks significantly reduced IRLS scores from baseline values (-13 to -14 vs -9) and produced significantly higher proportions of CGI-I responders (68-75% vs 51%) compared with placebo. Pramipexole was generally well tolerated, with most adverse events being transient and of mild to moderate severity.

  5. Transiliac Leg Lengthening in Poliomyelitis

    Directory of Open Access Journals (Sweden)

    Baghdadi Taghi

    2009-10-01

    Full Text Available The development and widespread use of a prophylactic vaccine significantly reduced the incidence of poliomyelitis. At present we more commonly encounter with poliomyelitis sequelae especially in developing countries. We evaluate the results of a modified innominate osteotomy for leg length discrepancy in poliomyelitis. Instead of triangular bone graft as in Salter’s innominate osteotomy , a trapezoidal bone graft from the ilium is inserted in the site of osteotomy after gradual distraction of the limb. 25 patients (9 males and 16 females with mean age of 25 years (17-37 years were treated by this method. All of them had poliomyelitis with limb shortening. At a mean follow-up of 7 years (3 months to 17 years an average of 3 cm (2.5-3.5 was achieved. Complication was seen in three patients including injury to the lateral cutaneouns nerve of thigh and displacement of osteotomy in two patients .except in one all of the patients satisfied with the operation. We believe this method is safe, effective and cost-benefit for treating of moderate shortening of the lower limb in poliomyelitis.

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

    Science.gov (United States)

    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

  7. Modelling and Control of Robotic Leg as Assistive Device

    Science.gov (United States)

    Jingye, Yee; Zain, Badrul Aisham bin Md

    2017-10-01

    The ageing population (people older than 60 years old) is expected to constitute 21.8% of global population by year 2050. When human ages, bodily function including locomotors will deteriorate. Besides, there are hundreds of thousands of victims who suffer from multiple health conditions worldwide that leads to gait impairment. A promising solution will be the lower limb powered-exoskeleton. This study is to be a start-up platform to design a lower limb powered-exoskeleton for a normal Malaysian male, by designing and simulating the dynamic model of a 2-link robotic leg to observe its behaviour under different input conditions with and without a PID controller. Simulink in MATLAB software is used as the dynamic modelling and simulation software for this study. It is observed that the 2-links robotic leg behaved differently under different input conditions, and perform the best when it is constrained and controlled by PID controller. Simulink model is formed as a foundation for the upcoming researches and can be modified and utilised by the future researchers.

  8. Genetic parameters for claw and leg health, foot and leg conformation, and locomotion in Danish Holsteins

    DEFF Research Database (Denmark)

    Laursen, M. V.; Boelling, D.; Mark, Thomas

    2009-01-01

    The purpose of this study was to estimate the genetic correlations among claw and leg health and potential indicator traits. Claw health was defined as absence of heel horn erosion, interdigital dermatitis, interdigital phlegmon, interdigital hyperplasia, laminitis, and sole ulcer. Leg health was...... as separate traits in genetic evaluations that also include the useful indicator traits to compensate for low heritability of the health traits.......The purpose of this study was to estimate the genetic correlations among claw and leg health and potential indicator traits. Claw health was defined as absence of heel horn erosion, interdigital dermatitis, interdigital phlegmon, interdigital hyperplasia, laminitis, and sole ulcer. Leg health......,877 Danish Holstein cows in first lactation. Binary health traits were divided into 3 subcategories: claw health, leg health, and absence of all claw and leg disorders. Genetic (r(g)) and phenotypic correlations were estimated using a bivariate linear sire model and REML. Estimated heritabilities were 0...

  9. Clinical quality indicators of venous leg ulcers

    DEFF Research Database (Denmark)

    Kjaer, Monica L; Mainz, Jan; Soernsen, Lars T

    2005-01-01

    In the clinical setting, diagnosis and treatment of venous leg ulcers can vary considerably from patient to patient. The first step to reducing this variation is to document venous leg ulcer care through use of quantitative scientific documentation principles. This requires the development of valid...... and reliable evidence-based quality indicators of venous leg ulcer care. A Scandinavian multidisciplinary, cross-sectional panel of wound healing experts developed clinical quality indicators on the basis of scientific evidence from the literature and subsequent group nominal consensus of the panel......; an independent medical doctor tested the feasibility and reliability of these clinical indicators, assessing the quality of medical technical care on 100 consecutive venous leg ulcer patients. Main outcome measures were healing, recurrence, pain, venous disease diagnosis, differential diagnosis and treatment...

  10. Genetics Home Reference: restless legs syndrome

    Science.gov (United States)

    ... PubMed Trenkwalder C, Paulus W. Restless legs syndrome: pathophysiology, clinical presentation and management. Nat Rev Neurol. 2010 ... newborn screening? New Pages MDA5 deficiency type 2 diabetes mitochondrial complex I deficiency All New & Updated Pages ...

  11. Passive zero-gravity leg restraint

    Science.gov (United States)

    Miller, Christopher R. (Inventor)

    1989-01-01

    A passive zero or microgravity leg restraint is described which includes a central support post with a top and a bottom. Extending from the central support post are a calf pad tab, to which calf pad is attached, and a foot pad tab, to which foot tab is attached. Also extending from central support post are knee pads. When the restraint is in use the user's legs are forced between pads by a user imposed scissors action of the legs. The user's body is then supported in a zero or microgravity neutral body posture by the leg restraint. The calf pad has semi-ridig elastic padding material covering structural stiffener. The foot pad has padding material and a structural stiffener. Knee pads have s structural tube stiffener at their core.

  12. A novel approach to gait synchronization and transition for reconfigurable walking platforms

    Directory of Open Access Journals (Sweden)

    Shunsuke Nansai

    2015-04-01

    Full Text Available Legged robots based on one degree-of-freedom reconfigurable planar leg mechanisms, that are capable of generating multiple useful gaits, are highly desired due to the possibility of handling environments and tasks of high complexity while maintaining simple control schemes. An essential consideration in these reconfigurable legged robots is to attain stability in motion, at rest as well as while transforming from one configuration to another with the minimum number of legs as long as the full range of their walking patterns, resulting from the different gait cycles of their legs, is achieved. To this end, in this paper, we present a method for the generation of input joint trajectories to properly synchronize the movement of quadruped robots with reconfigurable legs. The approach is exemplified in a four-legged robot with reconfigurable Jansen legs capable of generating up to six useful different gait cycles. The proposed technique is validated through simulated results that show the platform׳s stability across its six feasible walking patterns and during gait transition phases, thus considerably extending the capabilities of the non-reconfigurable design.

  13. Efficiency and Speed in Legged Robots

    Science.gov (United States)

    2011-03-22

    which we substitute into (4.42) : ( -mv s J O=-km+ mvc -k __ c __ V v 2 c c 46 (4.43) (4.44) (4.45) (4.46) to fInd the switching curve m 3 s...Legged Mechanisms. IVSS. Traverse City, MI Muench, P., Alexander, J., Quinn, R., & Aschenbeck, K. (2005) Pneumatic Spring for Legged Walker. SPIE

  14. Microgravity, Mesh-Crawling Legged Robots

    Science.gov (United States)

    Behar, Alberto; Marzwell, Neville; Matthews, Jaret; Richardson, Krandalyn; Wall, Jonathan; Poole, Michael; Foor, David; Rodgers, Damian

    2008-01-01

    The design, fabrication, and microgravity flight-testing are part of a continuing development of palm-sized mobile robots that resemble spiders (except that they have six legs apiece, whereas a spider has eight legs). Denoted SpiderBots (see figure), they are prototypes of proposed product line of relatively inexpensive walking robots that could be deployed in large numbers to function cooperatively in construction, repair, exploration, search, and rescue activities in connection with exploration of outer space and remote planets.

  15. The short term effects of straight leg raise neurodynamic treatment on pressure pain and vibration thresholds in individuals with spinally referred leg pain.

    Science.gov (United States)

    Ridehalgh, Colette; Moore, Ann; Hough, Alan

    2016-06-01

    Limited research exists for the effects of neurodynamic treatment techniques. Understanding short term physiological outcomes could help to better understand immediate benefits or harm of treatment. To assess the short-term effects of a straight leg raise (SLR) tensioner 'intervention' on pressure pain thresholds (PPT) and vibration thresholds (VT), and establish if additional factors influence outcome in individuals with spinally referred leg pain. Experimental, repeated measures. Sixty seven participants (mean age (SD) 52.9 (13.3), 33 female) with spinally referred leg pain were divided into 3 sub-groups: somatic referred pain, radicular pain and radiculopathy. Individuals were assessed for central sensitisation (CS) and completed 5 disability and psychosocial questionnaires. PPT and VT were measured pre and post a 3 × 1 min SLR tensioner intervention. No significant differences (p > 0.05) were found between the 3 groups for either outcome measure, or after treatment. Slight improvements in VT were seen in the radiculopathy group after treatment, but were not significant. Only 2 participants were identified with CS. Disability and psychological factors were not significantly different at baseline between the 3 sub-groups, and did not correlate with the outcome measures. No beneficial effects of treatment were found, but the trend for a decrease in VT indicated that even in individuals with radiculopathy, no detrimental changes to nerve function occurred. Psychosocial factors and levels of disability did not influence short term outcome of SLR treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Update on normal tension glaucoma

    Directory of Open Access Journals (Sweden)

    Jyotiranjan Mallick

    2016-01-01

    Full Text Available Normal tension glaucoma (NTG is labelled when typical glaucomatous disc changes, visual field defects and open anterior chamber angles are associated with intraocular pressure (IOP constantly below 21 mmHg. Chronic low vascular perfusion, Raynaud's phenomenon, migraine, nocturnal systemic hypotension and over-treated systemic hypertension are the main causes of normal tension glaucoma. Goldmann applanation tonometry, gonioscopy, slit lamp biomicroscopy, optical coherence tomography and visual field analysis are the main tools of investigation for the diagnosis of NTG. Management follows the same principles of treatment for other chronic glaucomas: To reduce IOP by a substantial amount, sufficient to prevent disabling visual loss. Treatment is generally aimed to lower IOP by 30% from pre-existing levels to 12-14 mmHg. Betaxolol, brimonidine, prostaglandin analogues, trabeculectomy (in refractory cases, systemic calcium channel blockers (such as nifedipine and 24-hour monitoring of blood pressure are considered in the management of NTG. The present review summarises risk factors, causes, pathogenesis, diagnosis and management of NTG.

  17. Three cross leg flaps for lower leg reconstruction of Gustilo type III C open fracture.

    Science.gov (United States)

    Sano, Kazufumi; Ozeki, Satoru; Sugimoto, Ichiro; Ogawa, Masato

    2016-01-01

    A 60 year old male had Gustilo type III C open fracture of the right lower leg. After radical debridement, the large open defect including certain loss of the bone tissue was successfully augmented and covered, by consecutive three cross-leg flaps, which consisted of the free rectus abdominis musculocutaneous flap, the fibula osteocutaneous flap and the conventional sural flap. Although indication for amputation or preservation is decided with multiple factors in each case, a strategic combination of cross-leg flap, free flap, external fixation and vascular delay could increase the potential of preservation of the lower leg with even disastrous Gustilo type III C.

  18. Three cross leg flaps for lower leg reconstruction of Gustilo type III C open fracture

    Directory of Open Access Journals (Sweden)

    Kazufumi Sano

    2016-01-01

    Full Text Available A 60 year old male had Gustilo type III C open fracture of the right lower leg. After radical debridement, the large open defect including certain loss of the bone tissue was successfully augmented and covered, by consecutive three cross-leg flaps, which consisted of the free rectus abdominis musculocutaneous flap, the fibula osteocutaneous flap and the conventional sural flap. Although indication for amputation or preservation is decided with multiple factors in each case, a strategic combination of cross-leg flap, free flap, external fixation and vascular delay could increase the potential of preservation of the lower leg with even disastrous Gustilo type III C.

  19. Surface tension and dynamics of fingering patterns

    OpenAIRE

    Magdaleno Escar, Francesc Xavier; Casademunt i Viader, Jaume

    1998-01-01

    We study the minimal class of exact solutions of the Saffman-Taylor problem with zero surface tension, which contains the physical fixed points of the regularized (non-zero surface tension) problem. New fixed points are found and the basin of attraction of the Saffman-Taylor finger is determined within that class. Specific features of the physics of finger competition are identified and quantitatively defined, which are absent in the zero surface tension case. This has dramatic consequences f...

  20. The Surface Tension of Pure Liquid Compounds,

    Science.gov (United States)

    The surface tension tables presented herein are the result of a literature survey, evaluation, and compilation of data of some 2200 pure liquid... surface tension values to establish the regression curves and their equations. The constants of the equations (slope and intercept), together with the...standard deviations are given for each compound. The selection factors establishing criteria of quality of surface tension data are discussed. These

  1. Coupling of marine riser and tensioner system

    OpenAIRE

    Olssøn, Tor Trainer

    2011-01-01

    A coupled model of a marine riser and a tensioner system is built. The riser is modeled using the multi-body dynamics program MSC Adams, and the tensioner system using the powerful controls and systems simulation tool, MSC Easy5. The hydrodynamic forces on the marine riser are calculated according to linear wave theory, and implemented in the model using a custom made subroutine. The riser is modeled using flexible beam elements according to Timoshenko beam theory. The tensioner system is...

  2. Isokinetic leg strength and power in elite handball players.

    Science.gov (United States)

    González-Ravé, José M; Juárez, Daniel; Rubio-Arias, Jacobo A; Clemente-Suarez, Vicente J; Martinez-Valencia, María A; Abian-Vicen, Javier

    2014-06-28

    Isokinetic strength evaluation of the knee flexion and extension in concentric mode of contraction is an important part of the comprehensive evaluation of athletes. The aims of this study were to evaluate the isokinetic knee peak torque in both the extension and flexion movement in the dominant and non-dominant leg, and the relationship with jumping performance. Twelve elite male handball players from the top Spanish handball division voluntary participated in the study (age 27.68 ± 4.12 years; body mass 92.89 ± 12.34 kg; body height 1.90 ± 0.05 m). The knee extensor and flexor muscle peak torque of each leg were concentrically measured at 60º/s and 180º/s with an isokinetic dynamometer. The Squat Jump and Countermovement Jump were performed on a force platform to determine power and vertical jump height. Non-significant differences were observed between legs in the isokinetic knee extension (dominant= 2.91 ± 0.53 Nm/kg vs non-dominant = 2.70 ± 0.47 Nm/kg at 60º/s; dominant = 1.90 ± 0.31 Nm/kg vs non-dominant = 1.83 ± 0.29 Nm/kg at 180º/s) and flexion peak torques (dominant = 1.76 ± 0.29 Nm/kg vs non-dominant = 1.72 ± 0.39 Nm/kg at 60º/s; dominant = 1.30 ± 0.23 Nm/kg vs non-dominant = 1.27 ± 0.35 Nm/kg at 180º/s). Low and non-significant correlation coefficients were found between the isokinetic peak torques and vertical jumping performance (SJ = 31.21 ± 4.32 cm; CMJ = 35.89 ± 4.20 cm). Similar isokinetic strength was observed between the legs; therefore, no relationship was found between the isokinetic knee flexion and extension peak torques as well as vertical jumping performance in elite handball players.

  3. Actin filaments as tension sensors.

    Science.gov (United States)

    Galkin, Vitold E; Orlova, Albina; Egelman, Edward H

    2012-02-07

    The field of mechanobiology has witnessed an explosive growth over the past several years as interest has greatly increased in understanding how mechanical forces are transduced by cells and how cells migrate, adhere and generate traction. Actin, a highly abundant and anomalously conserved protein, plays a large role in forming the dynamic cytoskeleton that is so essential for cell form, motility and mechanosensitivity. While the actin filament (F-actin) has been viewed as dynamic in terms of polymerization and depolymerization, new results suggest that F-actin itself may function as a highly dynamic tension sensor. This property may help explain the unusual conservation of actin's sequence, as well as shed further light on actin's essential role in structures from sarcomeres to stress fibers. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Bilateral differences in muscle fascicle architecture are not related to the preferred leg in jumping athletes.

    Science.gov (United States)

    Aeles, Jeroen; Lenchant, Sietske; Vanlommel, Liesbeth; Vanwanseele, Benedicte

    2017-07-01

    In many sports, athletes have a preferred leg for sport-specific tasks, such as jumping, which leads to strength differences between both legs, yet the underlying changes in force-generating mechanical properties of the muscle remain unknown. The purpose of this study was to investigate whether the muscle architecture of the medial gastrocnemius (MG) is different between both legs in well-trained jumping athletes and untrained individuals. In addition, we investigated the effect of two ankle joint positions on ultrasound muscle architecture measurements. Muscle architecture of both legs was measured in 16 athletes and 11 untrained individuals at two ankle joint angles: one with the ankle joint in a tendon slack length (TSL) angle and one in a 90° angle. Fascicle lengths and pennation angles at TSL were not different between the preferred and non-preferred legs in either group. The comparison between groups showed no difference in fascicle length, but greater pennation angles were found in the athletes (21.7° ± 0.5°) compared to the untrained individuals (19.8° ± 0.6°). Analyses of the muscle architecture at a 90° angle yielded different results, mainly in the comparison between groups. These results provide only partial support for the notion of training-induced changes in muscle architecture as only differences in pennation angles were found between athletes and untrained individuals. Furthermore, our results provide support to the recommendation to take into account the tension-length relationship and to measure muscle architecture at individually determined tendon slack joint angles.

  5. Effect of leg length on ROM, VJ and leg dexterity in dance.

    Science.gov (United States)

    Wyon, M A; Nevill, A M; Dekker, K; Brown, D D; Clarke, F; Pelly, J; Koutedakis, Y

    2010-09-01

    We investigated the associations between leg length and specific ballet movements in different skill groups. Volunteers were from an undergraduate dance programme (n=18), a pre-professional school (n=43) and from an elite classical ballet company (n=45). Individual data were collected for anthropometry, vertical jump, leg dexterity, and leg active and passive ROM. ANCOVA identified both main effects as significant with regard to vertical jump (gender Pgender, skill or leg length. Active and passive range of motion noted gender (P=0.001) and skill (P<0.001) differences. Leg length was found to be negatively associated with both active and passive ROM (P=0.002). In conclusion, the present data highlight the diverse and conflicting effects of leg length on fundamental ballet skills. The longer legs that benefit vertical jump have a negative influence on range of motion and leg dexterity except for highly skilled dancers, who through skill, seem to have overcome the effects of some of these dichotomies. Georg Thieme Verlag KG Stuttgart . New York.

  6. Diurnal variations in lower leg subcutaneous blood flow rate in patients with chronic venous leg ulcers

    DEFF Research Database (Denmark)

    Sindrup, J H; Kastrup, J; Kristensen, J K

    1991-01-01

    The blood flow rate in subcutaneous adipose tissue was measured on the lower legs of 11 patients with chronic lower-leg venous insufficiency and ulceration and in eight age-matched control subjects for 12-20 h, under ambulatory conditions, using the 133Xe wash-out technique with portable Cadmium...

  7. Single-leg squats can predict leg alignment in dancers performing ballet movements in "turnout".

    Science.gov (United States)

    Hopper, Luke S; Sato, Nahoko; Weidemann, Andries L

    2016-01-01

    The physical assessments used in dance injury surveillance programs are often adapted from the sports and exercise domain. Bespoke physical assessments may be required for dance, particularly when ballet movements involve "turning out" or external rotation of the legs beyond that typically used in sports. This study evaluated the ability of the traditional single-leg squat to predict the leg alignment of dancers performing ballet movements with turnout. Three-dimensional kinematic data of dancers performing the single-leg squat and five ballet movements were recorded and analyzed. Reduction of the three-dimensional data into a one-dimensional variable incorporating the ankle, knee, and hip joint center positions provided the strongest predictive model between the single-leg squat and the ballet movements. The single-leg squat can predict leg alignment in dancers performing ballet movements, even in "turned out" postures. Clinicians should pay careful attention to observational positioning and rating criteria when assessing dancers performing the single-leg squat.

  8. One-legged endurance training: leg blood flow and oxygen extraction during cycling exercise

    DEFF Research Database (Denmark)

    Rud, B; Foss, O; Krustrup, Peter

    2012-01-01

    Aim: As a consequence of enhanced local vascular conductance, perfusion of muscles increases with exercise intensity to suffice the oxygen demand. However, when maximal oxygen uptake (VO(2) max) and cardiac output are approached, the increase in conductance is blunted. Endurance training increases...... muscle metabolic capacity, but to what extent that affects the regulation of muscle vascular conductance during exercise is unknown. Methods: Seven weeks of one-legged endurance training was carried out by twelve subjects. Pulmonary VO(2) during cycling and one-legged cycling was tested before and after...... training, while VO(2) of the trained leg (TL) and control leg (CL) during cycling was determined after training. Results: VO(2) max for cycling was unaffected by training, although one-legged VO(2) max became 6.7 (2.3)% (mean ± SE) larger with TL than with CL. Also TL citrate synthase activity was higher...

  9. Levodopa for restless legs syndrome.

    Science.gov (United States)

    Scholz, Hanna; Trenkwalder, Claudia; Kohnen, Ralf; Riemann, Dieter; Kriston, Levente; Hornyak, Magdolna

    2011-02-16

    Levodopa plus dopamine decarboxylase inhibitor is a common treatment for restless legs syndrome (RLS). To evaluate efficacy and safety of levodopa for RLS compared to placebo and other active agents. We searched CENTRAL (The Cochrane Library 2008, Issue 4), MEDLINE, EMBASE, PsycINFO and CINAHL, from January 1985 to December 2008, reference lists of articles, and contacted pharmaceutical companies. We included double-blind randomised controlled trials (RCT) investigating levodopa treatment versus placebo or other treatment for at least seven days in patients with RLS (age ≥ 18 years). Outcomes included symptom severity, CGI-I, objective as well as self rated sleep parameters, quality of life, and safety parameters. Two authors extracted data, assessed risk of bias, and contacted pharmaceutical companies and authors for additional information. We collected dropouts due to adverse events and patients experiencing adverse events. Six placebo controlled and three active controlled RCTs were included (521 participants). Symptom severity (11 point rating scale, 0 points indicating no symptoms, 10 points indicating maximally severe symptoms) was more reduced with levodopa than placebo in two studies (mean difference (MD) -1.34, 95% confidence interval (CI) -2.18 to -0.5, P = 0.002). Periodic limb movements in sleep per hour of sleep (PLMS-Index; PLMSI) improved by -26.28/h compared to placebo (95% CI -30.53 to -22.02, P < 0.00001).The CGI-I changed more with levodopa than placebo in two studies (MD -1.25, 95% CI -1.89 to -0.62, P = 0.0001). In two studies, sleep quality (sleep questionnaire, visual analogue scale) showed a large effect (standardised mean difference (SMD) 0.92, 95% CI 0.52 to 1.33, P < 0.00001) whereas quality of life (50 mm Visual Analogue Scales) improved by 3.23 compared to placebo (95% CI 1.64 to 4.82, P < 0.0001). Few patients dropped out of treatment (3 of 218 patients) but more levodopa treated patients experienced adverse events than with placebo

  10. Increasing trunk flexion transforms human leg function into that of birds despite different leg morphology.

    Science.gov (United States)

    Aminiaghdam, Soran; Rode, Christian; Müller, Roy; Blickhan, Reinhard

    2017-02-01

    Pronograde trunk orientation in small birds causes prominent intra-limb asymmetries in the leg function. As yet, it is not clear whether these asymmetries induced by the trunk reflect general constraints on the leg function regardless of the specific leg architecture or size of the species. To address this, we instructed 12 human volunteers to walk at a self-selected velocity with four postures: regular erect, or with 30 deg, 50 deg and maximal trunk flexion. In addition, we simulated the axial leg force (along the line connecting hip and centre of pressure) using two simple models: spring and damper in series, and parallel spring and damper. As trunk flexion increases, lower limb joints become more flexed during stance. Similar to birds, the associated posterior shift of the hip relative to the centre of mass leads to a shorter leg at toe-off than at touchdown, and to a flatter angle of attack and a steeper leg angle at toe-off. Furthermore, walking with maximal trunk flexion induces right-skewed vertical and horizontal ground reaction force profiles comparable to those in birds. Interestingly, the spring and damper in series model provides a superior prediction of the axial leg force across trunk-flexed gaits compared with the parallel spring and damper model; in regular erect gait, the damper does not substantially improve the reproduction of the human axial leg force. In conclusion, mimicking the pronograde locomotion of birds by bending the trunk forward in humans causes a leg function similar to that of birds despite the different morphology of the segmented legs. © 2017. Published by The Company of Biologists Ltd.

  11. Transcutaneous oximetry measurements of the leg: comparing different measuring equipment and establishing values in healthy young adults.

    Science.gov (United States)

    Trinks, Tobias P; Blake, Denise F; Young, Derelle A; Thistlethwaite, Ken; Vangaveti, Venkat N

    2017-06-01

    Transcutaneous oximetry measurement (TCOM) is a non-invasive method of determining oxygen tension at the skin level using heated electrodes. To compare TCOM values generated by different machines and to establish lower limb TCOM values in a cohort of healthy individuals younger than 40 years of age. Sixteen healthy, non-smoking volunteers aged 18 to 39 years were recruited. TCOM was obtained at six locations on the lower leg and foot using three different Radiometer machines. Measurements were taken with subjects lying supine, breathing air. Except for one sensor site, there were no statistical differences in measurements obtained by the different TCOM machines. There was no statistical difference in measurements comparing left and right legs. Room air TCOM values for the different lower leg sites were (mean (SD) in mmHg): lateral leg 61.5 (9.2); lateral ankle 61.1 (9.7); medial ankle 59.1 (10.8); foot, first and second toe 63.4 (10.6); foot, fifth toe 59.9 (13.2) and plantar foot 74.1 (8.8). The overall mean TCOM value for the lower limb was 61 (10.8; 95% confidence intervals 60.05-62.0) mmHg. Lower-leg TCOM measurements using different Radiometer TCOM machines were comparable. Hypoxia has been defined as lower-leg TCOM values of less than 40 mmHg in non-diabetic patients and this is supported by our measurements. The majority (96.9%) of the lower leg TCOM values in healthy young adults are above the hypoxic threshold.

  12. Tension Pneumothorax following an Accidental Kerosene Poisoning ...

    African Journals Online (AJOL)

    Tension pneumothorax is a rare complication following an accidental kerosene poisoning. In such situation, a bed-side needle thoracocentesis is performed because of its potential of becoming fatal; hence its clinical importance. A case of 15 month old boy with tension pneumothorax following accidental kerosene ...

  13. Surface Tension Measurements of Chemically Modified Oleochemical

    Science.gov (United States)

    Surface tension is an important physical property of a substance, which plays a part in a variety of physical phenomenon relevant to many industrial processes. For example, the efficiency of the atomization of a fuel has been shown to be effected dramatically by surface tension and viscosity. Beca...

  14. Effect of Gravity on Surface Tension

    Science.gov (United States)

    Weislogel, M. M.; Azzam, M. O. J.; Mann, J. A.

    1998-01-01

    Spectroscopic measurements of liquid-vapor interfaces are made in +/- 1-g environments to note the effect of gravity on surface tension. A slight increase is detected at -1-g0, but is arguably within the uncertainty of the measurement technique. An increased dependence of surface tension on the orientation and magnitude of the gravitational vector is anticipated as the critical point is approached.

  15. A TOGgle for Tension at Kinetochores.

    Science.gov (United States)

    Cheerambathur, Dhanya K; Prevo, Bram; Desai, Arshad

    2016-06-02

    Differential stability of kinetochore-microtubule attachments at low versus high tension is critical for accurate chromosome segregation. Miller et al. find that a TOG domain microtubule-binding protein imparts intrinsic tension selectivity to kinetochore-microtubule attachments. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Intraoperative Development of Tension Pneumocephalus in a ...

    African Journals Online (AJOL)

    A review of studies discussing the role of N2O in tension pneumocephalus has also been included. The article heightens awareness among. CASE. REPORT. Intraoperative Development of Tension Pneumocephalus in a. Patient Undergoing Repair of a Cranial‑dural Defect Under. Nitrous Oxide Anesthesia. Mansher Singh ...

  17. Tension and robustness in multitasking cellular networks.

    Directory of Open Access Journals (Sweden)

    Jeffrey V Wong

    Full Text Available Cellular networks multitask by exhibiting distinct, context-dependent dynamics. However, network states (parameters that generate a particular dynamic are often sub-optimal for others, defining a source of "tension" between them. Though multitasking is pervasive, it is not clear where tension arises, what consequences it has, and how it is resolved. We developed a generic computational framework to examine the source and consequences of tension between pairs of dynamics exhibited by the well-studied RB-E2F switch regulating cell cycle entry. We found that tension arose from task-dependent shifts in parameters associated with network modules. Although parameter sets common to distinct dynamics did exist, tension reduced both their accessibility and resilience to perturbation, indicating a trade-off between "one-size-fits-all" solutions and robustness. With high tension, robustness can be preserved by dynamic shifting of modules, enabling the network to toggle between tasks, and by increasing network complexity, in this case by gene duplication. We propose that tension is a general constraint on the architecture and operation of multitasking biological networks. To this end, our work provides a framework to quantify the extent of tension between any network dynamics and how it affects network robustness. Such analysis would suggest new ways to interfere with network elements to elucidate the design principles of cellular networks.

  18. Surface tension measurements with a smartphone

    Science.gov (United States)

    Goy, Nicolas-Alexandre; Denis, Zakari; Lavaud, Maxime; Grolleau, Adrian; Dufour, Nicolas; Deblais, Antoine; Delabre, Ulysse

    2017-11-01

    Smartphones are increasingly used in higher education and at university in mechanics, acoustics, and even thermodynamics as they offer a unique way to do simple science experiments. In this article, we show how smartphones can be used in fluid mechanics to measure surface tension of various liquids, which could help students understand the concept of surface tension through simple experiments.

  19. City-as-a-Platform: The Rise of Participatory Innovation Platforms in Finnish Cities

    Directory of Open Access Journals (Sweden)

    Ari-Veikko Anttiroiko

    2016-09-01

    Full Text Available This article discusses the idea of city as a platform. The analysis focuses on the forms and implications of citizen involvement in publicly-supported participatory innovation platforms that facilitate urban economic development in the welfare society context. The discussion opens with a review of the smart city discourse, which in the context of economic development policy translates into cities’ need to support innovativeness by creating smart environments. Participatory innovation platform is a prime example of such an environment. The empirical section discusses three cases, those of the Finnish cities of Helsinki, Tampere, and Oulu. The analysis shows that platformization in the first half of the 2010s became a strategic focal area supported by national and EU programs. Platforms are used to support both urban revitalization and economic development, of which the former is based on representative and the latter on instrumental modes of participation. Platforms are well integrated with city governments, even though they vary greatly in terms of organizational forms and scopes. Democratic culture, welfarism, and redistributive policy provide contextual support for platformization by strengthening social inclusion, taming the growth machine, and easing the tensions between pro-growth and anti-growth coalitions.

  20. Initial tension loss in cerclage cables.

    Science.gov (United States)

    Ménard, Jérémie; Émard, Maxime; Canet, Fanny; Brailovski, Vladimir; Petit, Yvan; Laflamme, George Y

    2013-10-01

    Cerclage cables, frequently used in the management of fractures and osteotomies, are associated with a high failure rate and significant loosening during surgery. This study compared the capacity to maintain tension of different types of orthopaedic cable systems. Multifilament Cobalt-Chrome (CoCr) cables with four different crimp/clamp devices (DePuy, Stryker, Zimmer and Smith&Nephew) and one non-metallic Nylon (Ny) cable from Kinamed were instrumented with a load cell to measure tension during insertion. Significant tension loss was observed with crimping for all cables (Ptensioner led to an additional unexpected tension loss (CoCr-DePuy: 18%, CoCr-Stryker: 29%, CoCr-Smith&Nephew: 33%, Ny: 46%, and CoCr-Zimmer: 52%). The simple CoCr (DePuy) cable system outperformed the more sophisticated locking devices due to its significantly better ability to prevent tension loss. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Tension permeameter for deep borehole characterization

    Energy Technology Data Exchange (ETDEWEB)

    Sisson, J.B.; Honeycutt, T.K. [EG and G Idaho, Inc., Idaho Falls, ID (United States)

    1994-12-31

    The permeability of geologic materials is an important variable for estimating the rate of transport of contaminants from waste sites. To date, permeability has been estimated in the laboratory from measurements made on small cores, under hydrologic conditions far removed from those of the field. Available field instruments cannot estimate permeabilities at depth under ambient conditions. The authors have constructed a borehole tension permeameter that is capable of operating at near field conditions and at depths of more than 30 m. The tension permeameter consists of a syringe pump, lightweight packer, semipermeable membrane, and pressure transducer, all controlled by a programmable logic controller. Water is metered at a fixed rate through the membrane while monitoring tension. The permeability is estimated from the steady pumping rate for the membrane geometry used at the measured water tension. The permeameter was used to estimate the permeability of Pancheri sandy loam at tensions of 0 to 150 cm.

  2. Well Leg Compartment Syndrome After Abdominal Surgery

    DEFF Research Database (Denmark)

    Christoffersen, Jens Krogh; Hove, Lars Dahlgaard; Mikkelsen, Kim Lyngby

    2017-01-01

    BACKGROUND: Well leg compartment syndrome (WLCS) is a complication to abdominal surgery. We aimed to identify risk factors for and outcome of WLCS in Denmark and literature. METHODS: Prospectively collected claims to the Danish Patient Compensation Association (DPCA) concerning WLCS after abdominal...... surgery (p = 0.04). Duration of the abdominal surgery was 4 times as important as the diagnostic delay for severity of the final outcome. DNPR recorded 4 new cases/year, and half were reported to DPCA. CONCLUSION: The first 24 h following abdominal surgery of >4 h' duration with elevated legs observation...... for WLCS should be standard. Pain in the calf is indicative of WLCS, and elevated serum CK can support the diagnosis. Mannitol infusion and acute four-compartment fasciotomy of the lower leg is the treatment. The risk of severe outcome of WLCS increases with duration of the primary operation. A broad...

  3. Conjoined legs: Sirenomelia or caudal regression syndrome?

    Directory of Open Access Journals (Sweden)

    Sakti Prasad Das

    2013-01-01

    Full Text Available Presence of single umbilical persistent vitelline artery distinguishes sirenomelia from caudal regression syndrome. We report a case of a12-year-old boy who had bilateral umbilical arteries presented with fusion of both legs in the lower one third of leg. Both feet were rudimentary. The right foot had a valgus rocker-bottom deformity. All toes were present but rudimentary. The left foot showed absence of all toes. Physical examination showed left tibia vara. The chest evaluation in sitting revealed pigeon chest and elevated right shoulder. Posterior examination of the trunk showed thoracic scoliosis with convexity to right. The patient was operated and at 1 year followup the boy had two separate legs with a good aesthetic and functional results.

  4. Dimensional synthesis of a leg mechanism

    Science.gov (United States)

    Pop, F.; Lovasz, E.-Ch; Pop, C.; Dolga, V.

    2016-08-01

    An eight bar leg mechanism dimensional synthesis is presented. The mathematical model regarding the synthesis is described and the results obtained after computation are verified with help of 2D mechanism simulation in Matlab. This mechanism, inspired from proposed solution of Theo Jansen, is integrated into the structure of a 2 DOF quadruped robot. With help of the kinematic synthesis method described, it is tried to determine new dimensions for the mechanism, based on a set of initial conditions. These are established by taking into account the movement of the end point of the leg mechanism, which enters in contact with the ground, during walking. An optimization process based on the results obtained can be conducted further in order to find a better solution for the leg mechanism.

  5. Leg Spasticity and Ambulation in Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Swathi Balantrapu

    2014-01-01

    Full Text Available Background. Spasticity of the legs is common in multiple sclerosis (MS, but there has been limited research examining its association with ambulatory outcomes. Objective. This study examined spasticity of the legs and its association with multiple measures of ambulation in persons with MS. Methods. The sample included 84 patients with MS. Spasticity of the legs was measured using a 5-point rating scale ranging between 0 (normal and 4 (contracted. Patients completed the 6-minute walk (6 MW, timed 25 foot walk (T25FW, and timed up-and-go (TUG, and O2 cost of walking was measured during the 6 MW. The patients undertook two walking trials on a GAITRite (CIR systems, Inc. for measuring spatial and temporal parameters of gait. The patients completed the Multiple Sclerosis Walking Scale-12 (MSWS-12 and wore an accelerometer over a seven-day period. Results. 52% (n=44 of the sample presented with spasticity of the legs. Those with leg spasticity had significantly worse ambulation as measured by 6 MW (P=0.0001, d=-0.86, T25FW (P=0.003,d=0.72, TUG (P=0.001, d=0.84, MSWS-12 (P=0.0001,d=1.09, O2 cost of walking (P=0.001, d=0.75, average steps/day (P<0.05, d=-0.45, and walking velocity (P<0.05, d=-0.53 and cadence (P<0.05, d=-0.46. Conclusion. Leg spasticity was associated with impairments in ambulation, including alterations in spatiotemporal parameters and free-living walking.

  6. Reduction in wire tension caused by wire clamping and wire tensioner removal: an experimental Ilizarov frame study.

    Science.gov (United States)

    La Russa, Valentina; Skallerud, Bjørn; Klaksvik, Jomar; Foss, Olav A

    2011-03-01

    The stability of an external ring fixator mainly depends on wire tension. Wire fixators should maintain the tension during both wire clamping to the ring and removal of the tensioner device. In the present study the loss in wire tension related to fixator clamping and wire tensioner removal using three different wire fixator designs was studied. The fixators were based on two different cannulated bolts and a washer. Effects from two different pretension levels in combination with three different bolt torque levels upon loss in wire tension were described. Emitted wire vibration frequency was used to assess the corresponding wire tension. Wire tension was determined after each wire fixator tightening and after the removal of the wire tensioner. Increased bolt torque led to a small decrease in tension for both pretension levels. A considerable higher tension loss was measured when removing the wire tensioner. In all cases, the combination of a new cannulated bolt and a washer maintained the highest tension.

  7. [Contact eczema in patients with leg ulcers].

    Science.gov (United States)

    Degreef, H; Dooms-Goossens, A; Gladys, K

    1986-01-01

    Patients with leg ulcers or varicose eczema suffer much more often from contact eczema due to the local application of pharmaceutical preparations than patients suffering from other dermatological problems (even those of eczematous origin). This contact allergy may concern not only the active ingredient but also the excipient, the preservative, or even the perfume. In all cases of leg ulcers, of varicose eczema, but also of badly healed ulcers, epicutaneous tests should be carried out with all the components of the pharmaceutical preparations concerned. Moreover, the pharmaceutical industry really must perfect non-allergenic preparations.

  8. Dynamic response signatures of a scaled model platform for floating wind turbines in an ocean wave basin

    Science.gov (United States)

    Jaksic, V.; O'Shea, R.; Cahill, P.; Murphy, J.; Mandic, D. P.; Pakrashi, V.

    2015-01-01

    Understanding of dynamic behaviour of offshore wind floating substructures is extremely important in relation to design, operation, maintenance and management of floating wind farms. This paper presents assessment of nonlinear signatures of dynamic responses of a scaled tension-leg platform (TLP) in a wave tank exposed to different regular wave conditions and sea states characterized by the Bretschneider, the Pierson–Moskowitz and the JONSWAP spectra. Dynamic responses of the TLP were monitored at different locations using load cells, a camera-based motion recognition system and a laser Doppler vibrometer. The analysis of variability of the TLP responses and statistical quantification of their linearity or nonlinearity, as non-destructive means of structural monitoring from the output-only condition, remains a challenging problem. In this study, the delay vector variance (DVV) method is used to statistically study the degree of nonlinearity of measured response signals from a TLP. DVV is observed to create a marker estimating the degree to which a change in signal nonlinearity reflects real-time behaviour of the structure and also to establish the sensitivity of the instruments employed to these changes. The findings can be helpful in establishing monitoring strategies and control strategies for undesirable levels or types of dynamic response and can help to better estimate changes in system characteristics over the life cycle of the structure. PMID:25583866

  9. Dynamic response signatures of a scaled model platform for floating wind turbines in an ocean wave basin.

    Science.gov (United States)

    Jaksic, V; O'Shea, R; Cahill, P; Murphy, J; Mandic, D P; Pakrashi, V

    2015-02-28

    Understanding of dynamic behaviour of offshore wind floating substructures is extremely important in relation to design, operation, maintenance and management of floating wind farms. This paper presents assessment of nonlinear signatures of dynamic responses of a scaled tension-leg platform (TLP) in a wave tank exposed to different regular wave conditions and sea states characterized by the Bretschneider, the Pierson-Moskowitz and the JONSWAP spectra. Dynamic responses of the TLP were monitored at different locations using load cells, a camera-based motion recognition system and a laser Doppler vibrometer. The analysis of variability of the TLP responses and statistical quantification of their linearity or nonlinearity, as non-destructive means of structural monitoring from the output-only condition, remains a challenging problem. In this study, the delay vector variance (DVV) method is used to statistically study the degree of nonlinearity of measured response signals from a TLP. DVV is observed to create a marker estimating the degree to which a change in signal nonlinearity reflects real-time behaviour of the structure and also to establish the sensitivity of the instruments employed to these changes. The findings can be helpful in establishing monitoring strategies and control strategies for undesirable levels or types of dynamic response and can help to better estimate changes in system characteristics over the life cycle of the structure. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  10. THE EFFECTS OF SINGLE LEG HOP PROGRESSION AND DOUBLE LEGS HOP PROGRESSION EXERCISE TO INCREASE SPEED AND EXPLOSIVE POWER OF LEG MUSCLE

    Directory of Open Access Journals (Sweden)

    Nining W. Kusnanik

    2015-05-01

    Full Text Available The main purpose of this study was to determine the effect of single leg hop progression and double legs hop progression exercise to increase speed and explosive power of leg muscles. Plyometric is one of the training methods that can increase explosive power. There are many models of plyometric training including single leg hop progression and double leg hop progression. This research was experimental using match subject design techniques. The subjects of this study were 39 students who joined basketball school club. There were 3 groups in this study: Group 1 were 13 students who given sin¬gle leg hop progression exercise, Group 2 were 13 students who given double legs hop progression exercise, Group 3 were 13 students who given conventional exercise. The data was collected during pre test and post test by testing 30m speed running and vertical jump. The data was analyzed using Analysis of Varians (Anova. It was found that there were significantly increased on speed and explosive power of leg muscles of Group 1 and Group 2. It can be stated that single leg hop progression exercise was more effective than double leg hop progression exercise. The recent findings supported the hypothesis that single leg hop progression and double legs hop progression exercise can increase speed and explosive power of leg muscles. These finding were supported by some previous studies (Singh, et al, 2011; Shallaby, H.K., 2010. The single leg hop progression is more effective than double legs hop progression. This finding was consistent with some previous evidences (McCurdy, et al, 2005; Makaruk et al, 2011.

  11. Whole-body-vibration-induced increase in leg muscle activity during different squat exercises.

    Science.gov (United States)

    Roelants, Machteld; Verschueren, Sabine M P; Delecluse, Christophe; Levin, Oron; Stijnen, Valère

    2006-02-01

    This study analyzed leg muscle activity during whole-body vibration (WBV) training. Subjects performed standard unloaded isometric exercises on a vibrating platform (Power Plate): high squat (HS), low squat (LS), and 1-legged squat (OL). Muscle activity of the rectus femoris, vastus lateralis, vastus medialis, and gastrocnemius was recorded in 15 men (age 21.2 +/- 0.8 years) through use of surface electromyography (EMG). The exercises were performed in 2 conditions: with WBV and without (control [CO]) a vibratory stimulus of 35 Hz. Muscle activation during WBV was compared with CO and with muscle activation during isolated maximal voluntary contractions (MVCs). Whole-body vibration resulted in a significantly higher (p < 0.05) EMG root-mean-square compared with CO in all muscle groups and all exercises (between +39.9 +/- 17.5% and +360.6 +/- 57.5%). The increase in muscle activity caused by WBV was significantly higher (p < 0.05) in OL compared with HS and LS. In conclusion, WBV resulted in an increased activation of the leg muscles. During WBV, leg muscle activity varied between 12.6 and 82.4% of MVC values.

  12. Leg symptoms of somatic, psychic, and unexplained origin in the population-based Bonn vein study.

    Science.gov (United States)

    Amsler, F; Rabe, E; Blättler, W

    2013-08-01

    To assess the somatic and psychic components of venous-type leg symptoms. The psychic versus somatic venous disease questionnaire (PsySoVDQ) was applied to 1,800 participants of the Bonn Vein Study (BVS) II. Factor analysis of the PsySoVDQ made it possible to distinguish a psychic component (PC; 5 items, Cronbach's alpha = 0.73) separate from a somatic component (SC; 4 items, Cronbach's alpha = 0.67). The PC reflected anxiety and inhibition, was prevalent in 39.8% and explained 7.3% of the BVS findings. Higher PC scores were typically found in younger, slim women of higher social status, with feelings of leg heaviness and tension, and reduced psychic quality of life. The SC prevailed in 37.4% and explained 16.5% of BVS findings. Typical SC scorers were older, overweight women with lower social status, more symptoms (including swelling), signs of chronic venous insufficiency, ultrasound-documented venous abnormalities, and reduced multidimensional quality of life. The SC's predictive accuracy for CEAP 2 and 3 (classification according to clinical findings, etiology, anatomy, pathophysiology) was equal to that of the BVS assessment. The PsySoVDQ identified somatic and psychic components of the widespread and frequently reported leg symptoms in the general population. Nevertheless, in the majority of subjects symptoms remained unexplained. A neuropsychological and neurobiological hypothesis is advanced. Copyright © 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  13. Dynamical Modeling of Surface Tension

    Science.gov (United States)

    Brackbill, Jeremiah U.; Kothe, Douglas B.

    1996-01-01

    In a recent review it is said that free-surface flows 'represent some of the difficult remaining challenges in computational fluid dynamics'. There has been progress with the development of new approaches to treating interfaces, such as the level-set method and the improvement of older methods such as the VOF method. A common theme of many of the new developments has been the regularization of discontinuities at the interface. One example of this approach is the continuum surface force (CSF) formulation for surface tension, which replaces the surface stress given by Laplace's equation by an equivalent volume force. Here, we describe how CSF formulation might be made more useful. Specifically, we consider a derivation of the CSF equations from a minimization of surface energy as outlined by Jacqmin (1996). This reformulation suggests that if one eliminates the computation of curvature in terms of a unit normal vector, parasitic currents may be eliminated. For this reformulation to work, it is necessary that transition region thickness be controlled. Various means for this, in addition to the one discussed by Jacqmin (1996), are discussed.

  14. Assessment of the vibration on the foam legged and sheet metal-legged passenger seat

    Directory of Open Access Journals (Sweden)

    L. Dahil

    2015-10-01

    Full Text Available In this study, it was aim ed to decrease the vibration reaching to passenger from the legs of vehicle seats. In order to determine the levels of vibrations reaching at passengers, a test pad placed under the passenger seat was used, and HVM100 device was used for digitizing the information obtained. By transferring the vibration data to system by using HVM100 device, the acceleration graphics were prepared with Blaze software. As a result, it was determined that the acceleration values of seat legs made of foam material were lower than that of seat legs made of 2 mm thick sheet metal, so they damped the vibration better.

  15. Segway robotic mobility platform

    Science.gov (United States)

    Nguyen, Hoa G.; Morrell, John; Mullens, Katherine D.; Burmeister, Aaron B.; Miles, Susan; Farrington, Nathan; Thomas, Kari M.; Gage, Douglas W.

    2004-12-01

    The Segway Robotic Mobility Platform (RMP) is a new mobile robotic platform based on the self-balancing Segway Human Transporter (HT). The Segway RMP is faster, cheaper, and more agile than existing comparable platforms. It is also rugged, has a small footprint, a zero turning radius, and yet can carry a greater payload. The new geometry of the platform presents researchers with an opportunity to examine novel topics, including people-height sensing and actuation modalities. This paper describes the history and development of the platform, its characteristics, and a summary of current research projects involving the platform at various institutions across the United States.

  16. Tension and Robustness in Multitasking Cellular Networks

    Science.gov (United States)

    Wong, Jeffrey V.; Li, Bochong; You, Lingchong

    2012-01-01

    Cellular networks multitask by exhibiting distinct, context-dependent dynamics. However, network states (parameters) that generate a particular dynamic are often sub-optimal for others, defining a source of “tension” between them. Though multitasking is pervasive, it is not clear where tension arises, what consequences it has, and how it is resolved. We developed a generic computational framework to examine the source and consequences of tension between pairs of dynamics exhibited by the well-studied RB-E2F switch regulating cell cycle entry. We found that tension arose from task-dependent shifts in parameters associated with network modules. Although parameter sets common to distinct dynamics did exist, tension reduced both their accessibility and resilience to perturbation, indicating a trade-off between “one-size-fits-all” solutions and robustness. With high tension, robustness can be preserved by dynamic shifting of modules, enabling the network to toggle between tasks, and by increasing network complexity, in this case by gene duplication. We propose that tension is a general constraint on the architecture and operation of multitasking biological networks. To this end, our work provides a framework to quantify the extent of tension between any network dynamics and how it affects network robustness. Such analysis would suggest new ways to interfere with network elements to elucidate the design principles of cellular networks. PMID:22577355

  17. Design and implementation of wire tension measurement system for MWPCs used in the STAR iTPC upgrade

    Science.gov (United States)

    Wang, Xu; Shen, Fuwang; Wang, Shuai; Feng, Cunfeng; Li, Changyu; Lu, Peng; Thomas, Jim; Xu, Qinghua; Zhu, Chengguang

    2017-07-01

    The STAR experiment at RHIC is planning to upgrade the Time Projection Chamber which lies at the heart of the detector. We have designed an instrument to measure the tension of the wires in the multi-wire proportional chambers (MWPCs) which will be used in the TPC upgrade. The wire tension measurement system causes the wires to vibrate and then it measures the fundamental frequency of the oscillation via a laser based optical platform. The platform can scan the entire wire plane, automatically, in a single run and obtain the wire tension on each wire with high precision. In this paper, the details about the measurement method and the system setup will be described. In addition, the test results for a prototype MWPC to be used in the STAR-iTPC upgrade will be presented.

  18. Legged Vehicle for Underwater Mobile Operations

    Science.gov (United States)

    1994-09-15

    N93-139 ___ Legged Vehicle for Underwater Mobile Operations Encl. (1): Progress Report, Prof. Joseph Ayers, Northeastern Univ. Gentlemen: This letter...gravity and searching. The following new modules have been implemented: * AntiGravity Recruiter - Allows recruitment of depressor for pitch and roll

  19. Parental smoking during pregnancy shortens offspring's legs.

    Science.gov (United States)

    Żądzińska, E; Kozieł, S; Borowska-Strugińska, B; Rosset, I; Sitek, A; Lorkiewicz, W

    2016-12-01

    One of the most severe detrimental environmental factors acting during pregnancy is foetal smoke exposure. The aim of this study was to assess the effect of maternal, paternal and parental smoking during pregnancy on relative leg length in 7- to 10-year-old children. The research conducted in the years 2001-2002 included 978 term-born children, 348 boys and 630 girls, at the age of 7-10 years. Information concerning the birth weight of a child was obtained from the health records of the women. Information about the mother's and the father's smoking habits during pregnancy and about the mothers' education level was obtained from a questionnaire. The influence of parental smoking on relative leg length, controlled for age, sex, birth weight and the mother's education, as a proxy measure of socioeconomic status, and controlled for an interaction between sex and birth weight, was assessed by an analysis of covariance, where relative leg length was the dependent variable, smoking and sex were the independent variables, and birth weight as well as the mother's education were the covariates. Three separate analyses were run for the three models of smoking habits during pregnancy: the mother's smoking, the father's smoking and both parents' smoking. Only both parents' smoking showed a significant effect on relative leg length of offspring. It is probable that foetal hypoxia caused by carbon monoxide contained in smoke decelerated the growth of the long bones of foetuses. Copyright © 2016 Elsevier GmbH. All rights reserved.

  20. Omnidirectional Wheel-Legged Hybrid Mobile Robot

    Directory of Open Access Journals (Sweden)

    István Vilikó

    2015-06-01

    Full Text Available The purpose of developing hybrid locomotion systems is to merge the advantages and to eliminate the disadvantages of different type of locomotion. The proposed solution combines wheeled and legged locomotion methods. This paper presents the mechatronic design approach and the development stages of the prototype.

  1. Leg og læring

    DEFF Research Database (Denmark)

    Pedersen, Annette

    2008-01-01

    Leg synes at have et potentiale som metode til at fremme læring. Men hvordan? Legen har en vis grad af parallelitet med den virkelige verden i dens interaktive og relationelle strukturer. Det bliver muligt at finde nye meninger i interaktioner, som refererer til vante interaktionsformer, men alli...

  2. Robust Bipedal Walking with Variable Leg Stiffness

    NARCIS (Netherlands)

    Visser, L.C.; Stramigioli, Stefano; Carloni, Raffaella

    The bipedal spring-mass model embodies important characteristics of human walking, and therefore serves as an important starting point in studying human-like walking for robots. In this paper, we propose to extend the bipedal spring-mass model with variable leg stiffness and exploit the potential of

  3. Clinical aspects of lower leg compartment syndrome

    NARCIS (Netherlands)

    Brand, Johan Gerard Henric van den

    2004-01-01

    A compartment syndrome is a condition in which increased pressure within a limited space compromises the circulation and function of tissues within that space. Although pathofysiology is roughly similar in chronic exertional and acute compartment syndrome of the lower leg, the clinical

  4. Dipoles on a Two-leg Ladder

    DEFF Research Database (Denmark)

    Gammelmark, Søren; Zinner, Nikolaj Thomas

    2013-01-01

    of lattice filling fractions, perpendicular hopping between the legs, and dipole interaction strength. We show that the system exhibits zig-zag ordering when the dipolar interactions are predominantly repulsive. As a function of dipole moment orientation with respect to the ladder, we find...

  5. Clinical Features of Restless Legs Syndrome

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-12-01

    Full Text Available Clinical characteristics of childhood-onset restless legs syndrome (RLS were studied in 32 (5.9% patients, <18 years of age, diagnosed with the disorder among 538 who attended the Pediatric Sleep Disorders Center with sleep-wake complaints, between January 2000 and March 2004, at the Mayo Clinic, Rochester, MN.

  6. Hereditary spherocytosis presenting as indolent leg ulcers

    Directory of Open Access Journals (Sweden)

    Muhammed K

    1997-01-01

    Full Text Available Indolent leg ulcertation, which is the rarest manifestation of hereditary spherocytosis, started at the age of 5 years affecting a 15-year-old boy and his mother is reported. Review of literature showed very few reports from India and abroad. The response to oral folic acid was excellent

  7. Chronic Lower Leg Pain in Athletes

    Science.gov (United States)

    Brewer, Rachel Biber; Gregory, Andrew J. M.

    2012-01-01

    Context: Chronic lower leg pain in athletes can be a frustrating problem for patients and a difficult diagnosis for clinicians. Myriad approaches have been suggested to evaluate these conditions. With the continued evolution of diagnostic studies, evidence-based guidance for a standard approach is unfortunately sparse. Evidence Acquisition: PubMed was searched from January 1980 to May 2011 to identify publications regarding chronic lower leg pain in athletes (excluding conditions related to the foot), including differential diagnosis, clinical presentation, physical examination, history, diagnostic workup, and treatment. Results: Leg pain in athletes can be caused by many conditions, with the most frequent being medial tibial stress syndrome; chronic exertional compartment syndrome, stress fracture, nerve entrapment, and popliteal artery entrapment syndrome are also considerations. Conservative management is the mainstay of care for the majority of causes of chronic lower leg pain; however, surgical intervention may be necessary. Conclusion: Chronic lower extremity pain in athletes includes a wide differential and can pose diagnostic dilemmas for clinicians. PMID:23016078

  8. Gastrothorax or tension pneumothorax: A diagnostic dilemma

    Directory of Open Access Journals (Sweden)

    Singh Sarvesh

    2011-01-01

    Full Text Available Gastrothorax, a rare complication following thoracoabdominal aortic aneurysm repair, is reported. The clinical features of a gastrothorax and tension pneumothorax are similar and thus, a gastrothorax can masquerade as a tension pneumothorax. The diagnosis is made by a high level of clinical suspicion, chest X-ray shows a distended stomach with air fluid levels and a computerised tomography is useful in assessing the diaphragm and establishing the positions of the various intra-abdominal organs. Also, the risk of an intercostal drainage tube placement and the role of nasogastric tube in avoiding the development of a tension gastrothorax is highlighted.

  9. Surface tension profiles in vertical soap films

    Science.gov (United States)

    Adami, N.; Caps, H.

    2015-01-01

    Surface tension profiles in vertical soap films are experimentally investigated. Measurements are performed by introducing deformable elastic objets in the films. The shape adopted by those objects once set in the film is related to the surface tension value at a given vertical position by numerically solving the adapted elasticity equations. We show that the observed dependency of the surface tension versus the vertical position is predicted by simple modeling that takes into account the mechanical equilibrium of the films coupled to previous thickness measurements.

  10. Venus Aerial Platform Study

    Science.gov (United States)

    Cutts, J. A.

    2017-11-01

    A Venus Aerial Platform Study, which was underway in early 2017, is assessing the science and technologies for exploring Venus with aerial vehicles in order to develop a Venus Aerial Platform Roadmap for the future exploration of the planet.

  11. Lower leg pain. Diagnosis and treatment of compartment syndromes and other pain syndromes of the leg.

    Science.gov (United States)

    Touliopolous, S; Hershman, E B

    1999-03-01

    Leg pain in athletes has many aetiologies. The clinician must strive to specifically define the clinical problem in order to administer the appropriate treatment for the athlete's condition. Clinical conditions in the leg causing symptoms in athletes include chronic exertional compartment syndrome (CECC), tendinitis, medial tibial stress syndrome, stress fractures, fascial defects, musculotendinous junction disruptions (tennis leg), popliteal artery entrapment syndrome, effort-induced venous thrombosis and nerve entrapment. Appropriate diagnostic studies are needed to allow accurate diagnosis. A work-up might include radiographs, bone scans and compartment pressure measurement. Many of these conditions relate to overuse and training errors. Conservative measures including rest, activity modification and rehabilitation will permit a gradual return to participation in sports. Some problems such as CECC, popliteal artery entrapment syndrome and nerve entrapment may require surgical intervention to allow the resolution of symptoms. Clinicians should be familiar with the range of problems causing leg pain in order to prescribe specific treatment for each athlete.

  12. Different fatigue-resistant leg muscles and EMG response during whole-body vibration.

    Science.gov (United States)

    Simsek, Deniz

    2017-12-01

    The purpose of this study was to determine the effects of static whole-body vibration (WBV) on the Electromyograhic (EMG) responses of leg muscles, which are fatigue-resistant in different manner. The study population was divided into two groups according to the values obtained by the Fatigue Index [Group I: Less Fatigue Resistant (LFR), n=11; Group II: More Fatigue Resistant (MFR), n=11]. The repeated electromyographic (EMG) activities of four leg muscles were analyzed the following determinants: (1) frequency (30 Hz, 35 Hz and 40 Hz); (2) stance position (static squat position); (3) amplitude (2 mm and 4 mm) and (4) knee flexion angle (120°), (5) vertical vibration platform. Vibration data were analyzed using Minitab 16 (Minitab Ltd, State College, PA, USA). The significance level was set at pfatigue (pvibration exercise and can serve to guide the development of training programs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Dynamic Model of Platform Manipulator with Six Degrees of Freedom

    Directory of Open Access Journals (Sweden)

    A. L. Lapikov

    2015-01-01

    Full Text Available The paper considers a solution of the relevant tasks related to deriving dynamic equations for the platform manipulators with 6 degrees of freedom. It presents a detailed analysis of the subject area, describes key problems arising in the course of research, and suggests their solution methods. The equations describing dynamics of the mechanical system under discussion were derived using Lagrange equation of the second kind. For this purpose Cartesian coordinates and three Euler angles (angles of precession, nutation and intrinsic rotation describing the orientation of moving frame of reference connected with the platform towards the base were chosen as generalized coordinates of the model. Such choice allowed us to simplify the derivation of the model considerably, because it was possible to represent a dependence of kinetic energy of the mechanical system on the generalized coordinates in an explicit form. In addition, formulation of kinetic energy was supplemented with correlations describing kinetic energy of the mechanism legs. During the derivation of equations for the legs velocities the part of the component defining a rotation movement of the leg against the joint of the base was ignored because of it was small in comparison with the component of linear separation. Besides, during the derivation of equations for kinetic energy of the legs, modified correlations for kinematics of platform manipulators with 6 degrees of freedom suggested in the previous papers of the authors were used.he paper examines a numerical example to solve a reverse dynamic problem in the case of equal harmonic changes of controlling forces. It was found out that under controlling forces described above the platform carries out harmonic advancing movements along the vertical axis.Further planning research concerns the extended capabilities of the model to consider the influence of the working load and to create algorithms for deriving dynamic models of a

  14. Pneumatic Artificial Muscles Force Modelling and the Position and Stiffness Control on the Knee Joint of the Musculoskeletal Leg

    Directory of Open Access Journals (Sweden)

    Jingtao Lei

    2017-03-01

    Full Text Available Pneumatic artificial muscles (PAMs have properties similar to biological muscle and are widely used in robotics as actuators. A musculoskeletal leg mechanism driven by PAMs is presented in this paper. The joint stiffness of the musculoskeletal bionic leg for jumping movement needs to be analysed. The synchronous control on the position and stiffness of the joint is important to improve the flexibility of leg. The accurate force model of PAM is the foundation to achieving better control and dynamic jumping performance. The experimental platform of PAM is conducted, and the static equal pressure experiments are performed to obtain the PAM force model. According to the testing data, parameter identification method is adopted to determine the force model of PAM. A simulation on the position and stiffness control of the knee joint is performed, and the simulation results show the effectiveness of the presented method.

  15. Mobile platform security

    CERN Document Server

    Asokan, N; Dmitrienko, Alexandra

    2013-01-01

    Recently, mobile security has garnered considerable interest in both the research community and industry due to the popularity of smartphones. The current smartphone platforms are open systems that allow application development, also for malicious parties. To protect the mobile device, its user, and other mobile ecosystem stakeholders such as network operators, application execution is controlled by a platform security architecture. This book explores how such mobile platform security architectures work. We present a generic model for mobile platform security architectures: the model illustrat

  16. Autonomous Control of Fluids in a Wide Surface Tension Range in Microfluidics.

    Science.gov (United States)

    Ge, Peng; Wang, Shuli; Liu, Yongshun; Liu, Wendong; Yu, Nianzuo; Zhang, Jianglei; Shen, Huaizhong; Zhang, Junhu; Yang, Bai

    2017-07-25

    In this paper, we report the preparation of anisotropic wetting surfaces that could control various wetting behaviors of liquids in a wide surface tension range (from water to oil), which could be employed as a platform for controlling the flow of liquids in microfluidics (MFs). The anisotropic wetting surfaces are chemistry-asymmetric "Janus" silicon cylinder arrays, which are fabricated via selecting and regulating the functional groups on the surface of each cylinder unit. Liquids (in a wide surface tension range) wet in a unidirectional manner along the direction that was modified by the group with large surface energy. Through introducing the Janus structure into a T-shaped pattern and integrating it with an identical T-shaped poly(dimethylsiloxane) microchannel, the as-prepared chips can be utilized to perform as a surface tension admeasuring apparatus or a one-way valve for liquids in a wide surface tension range, even oil. Furthermore, because of the excellent ability in controlling the flowing behavior of liquids in a wide surface tension range in an open system or a microchannel, the anisotropic wetting surfaces are potential candidates to be applied both in open MFs and conventional MFs, which would broaden the application fields of MFs.

  17. On-chip microfluidic generation of monodisperse bubbles for liquid interfacial tension measurement.

    Science.gov (United States)

    Wang, Chen; Cao, Jing; Zhou, Yue; Xia, Xing-Hua

    2018-01-01

    A novel microfluidic method for measuring liquid interfacial tension using monodisperse microbubbles generated in situ has been proposed. Instead of bulky gas supply used in traditional microfluidic devices, microbubbles are efficiently generated via water electrolysis in the devices. Since the bubble formation frequency is related to the interfacial tension of liquids used, thus, precisely measuring the interfacial tension of liquids in microfluidics can be achieved. In addition, it is found that during the microbubble formation, the electrochemical potential fluctuates regularly at controlled electrolysis current, and the fluctuating period depends on the microbubble generation rate. Therefore, the change in electrochemical potential can be directly used to monitor the bubble formation process, which avoids the use of an external optical detection system. As demonstration, the interfacial tension of isopentanol solutions with different concentrations was measured, and the results show good agreement with the ones obtained using the maximum bubble pressure method, confirming the accuracy of the present method. The proposed strategy offers a simple, low cost and accurate solution to measure the liquid interfacial tension confined in microfluidic channels. The present platform is easily constructed and facilely manipulated in common laboratories, which is expected to be widely used in microfluidic-based research and application fields. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. A colored leg banding technique for Amazona parrots

    Science.gov (United States)

    Meyers, J.M.

    1995-01-01

    A technique for individual identification of Amazona was developed using plastic leg bands. Bands were made from 5- and 7-mm-wide strips of laminated PVC coiled 2.5 times with an inside diameter 4-5 mm gt the maximum diameter of the parrot's leg. Seventeen parrots were captured in Puerto Rico, marked with individual plastic leg bands, and observed for 204-658 d with only one lost or damaged plastic band. Plastic leg bands did not cause injury to or calluses on parrots' legs. The plastic material used for making leg bands was available in 18 colors in 1994, which would allow unique marking of 306 individuals using one plastic leg band on each leg.

  19. The Dynamic Surface Tension of Water.

    Science.gov (United States)

    Hauner, Ines M; Deblais, Antoine; Beattie, James K; Kellay, Hamid; Bonn, Daniel

    2017-04-06

    The surface tension of water is an important parameter for many biological or industrial processes, and roughly a factor of 3 higher than that of nonpolar liquids such as oils, which is usually attributed to hydrogen bonding and dipolar interactions. Here we show by studying the formation of water drops that the surface tension of a freshly created water surface is even higher (∼90 mN m -1 ) than under equilibrium conditions (∼72 mN m -1 ) with a relaxation process occurring on a long time scale (∼1 ms). Dynamic adsorption effects of protons or hydroxides may be at the origin of this dynamic surface tension. However, changing the pH does not significantly change the dynamic surface tension. It also seems unlikely that hydrogen bonding or dipole orientation effects play any role at the relatively long time scale probed in the experiments.

  20. The Dynamic Surface Tension of Water

    Science.gov (United States)

    2017-01-01

    The surface tension of water is an important parameter for many biological or industrial processes, and roughly a factor of 3 higher than that of nonpolar liquids such as oils, which is usually attributed to hydrogen bonding and dipolar interactions. Here we show by studying the formation of water drops that the surface tension of a freshly created water surface is even higher (∼90 mN m–1) than under equilibrium conditions (∼72 mN m–1) with a relaxation process occurring on a long time scale (∼1 ms). Dynamic adsorption effects of protons or hydroxides may be at the origin of this dynamic surface tension. However, changing the pH does not significantly change the dynamic surface tension. It also seems unlikely that hydrogen bonding or dipole orientation effects play any role at the relatively long time scale probed in the experiments. PMID:28301160

  1. Modelling Tension Stiffening in Reinforced Concrete Structures

    DEFF Research Database (Denmark)

    Christiansen, Morten Bo; Nielsen, Mogens Peter

    1997-01-01

    Part I of the present thesis deals with crack formation in reinforced concrete and the phenomenon of tension stiffening in concrete tension rods reinforced with deformed bars.Two physical models are presented for uniaxial tension, and they are modified for application on beams subjected to pure...... predicted by the models are compared with experimental data from tests on tension rods as well as flexural beams.In the light of the simple assumptions made and the random nature of cracking, the accordance between the models and the test data is quite good.Part II of the present thesis deals...... of the simple assumptions, quite good accordance is found.Part III of the thesis deals with the deformations of a beam symmetrically loaded by two concentrated forces. In the shear-flexure beam model it is assumed that the load is carried by means of a stringer system and a diagonal stress field in the shear...

  2. ITS Platform North Denmark

    DEFF Research Database (Denmark)

    Lahrmann, Harry; Agerholm, Niels; Juhl, Jens

    2012-01-01

    This paper presents the project entitled “ITS Platform North Denmark” which is used as a test platform for Intelligent Transportation System (ITS) solutions. The platform consists of a newly developed GNSS/GPRS On Board Unit (OBU) to be installed in 500 cars, a backend server and a specially...

  3. Static balance according to hip joint angle of unsupported leg during one-leg standing.

    Science.gov (United States)

    Cha, Ju-Hyung; Kim, Jang-Joon; Ye, Jae-Gwan; Lee, Seul-Ji; Hong, Jeong-Mi; Choi, Hyun-Kyu; Choi, Ho-Suk; Shin, Won-Seob

    2017-05-01

    [Purpose] This study aimed to determine static balance according to hip joint angle of the unsupported leg during one-leg standing. [Subjects and Methods] Subjects included 45 healthy adult males and females in their 20s. During one-leg standing on the non-dominant leg, the position of the unsupported leg was classified according to hip joint angles of point angle was class. Static balance was then measured using a force plate with eyes open and closed. The total length, sway velocity, maximum deviation, and velocity on the mediolateral and anteroposterior axes of center of pressure were measured. [Results] In balance assessment with eyes open, there were significant differences between groups according to hip joint angle, except for maximum deviation on the anteroposterior axis. In balance assessment with eyes closed, there were significant differences between total length measurements at 0° and 30°, 60° and between 30° and 90°. There were significant differences between sway velocity measurements at 0° and 30° and between 30° and 90°. [Conclusion] Thus, there were differences in static balance according to hip joint angle. It is necessary to clearly identify the hip joint angle during one-leg standing testing.

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

    OpenAIRE

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

    2011-01-01

    Abstract 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 spri...

  5. Tension Hydrothorax Related to Disseminated Endometriosis

    Directory of Open Access Journals (Sweden)

    AnnaKate Deal, MD

    2016-01-01

    Full Text Available We present the case of a 34-year-old woman presenting to the emergency department (ED with dyspnea, cough, and fever. She was found to have a tension hydrothorax and was treated with ultrasound-guided thoracentesis in the ED. Subsequent inpatient evaluation showed the patient had disseminated endometriosis. Tension hydrothorax has not been previously described in the literature as a complication of this disease.

  6. Leadership matters: Tensions in evaluating leadership development

    OpenAIRE

    Jarvis, C.; Gulati, A.; McCririck, V.; Simpson, P.

    2013-01-01

    The Problem and Solution: This paper explores some of the tensions that required careful management in the design and delivery of a leadership development program. This discussion draws particularly upon a formal evaluation of two cohorts, each comprising approximately 20 senior managers working in adult social care. Complexity theory, notably Complex Responsive Processes of Relating, is used to make visible, explore and articulate the need to hold in tension apparently contradictory forces a...

  7. The accuracy of fine wire tensioners: a comparison of five tensioners used in hybrid and ring external fixation.

    Science.gov (United States)

    Roberts, Craig S; Antoci, Valentin; Antoci, Valentin; Voor, Michael J

    2004-03-01

    To compare the accuracy of 5 commonly available fine wire tensioners used in hybrid and ring external fixation. A laboratory investigation. The testing of 5 commonly available tensioners was performed with a servohydraulic test frame (MTS Bionix 858, Minneapolis, MN). The real wire tension data of each tensioner provided by the MTS were compared with corresponding nominal values. The percent error for each tensioner was calculated. Clinical ease of usage of the wire tensioners was also evaluated. The EBI tensioner was the most accurate (-0.17% to 0.09% error). The Smith and Nephew tensioner had a -13.97% to -8.61% error, the How medica tensioner a -12.48% to -10.86% error, and the Synthes tensioner a -0.2% to 24.28% error. The DePuyACE tensioner was the least accurate, with errors ranging from -36.76% to -30.92%. The Howmedica tensioner was the easiest to use, followed by the Smith and Nephew tensioner, the DePuyACE tensioner, the Synthes tensioner, and the EBI tensioner. Most commonly available tensioners tend to undertension. Future efforts should focus on the development of wire tensioners that combine accuracy and ease of usage.

  8. Oxygen tension level and human viral infections

    Energy Technology Data Exchange (ETDEWEB)

    Morinet, Frédéric, E-mail: frederic.morinet@sls.aphp.fr [Centre des Innovations Thérapeutiques en Oncologie et Hématologie (CITOH), CHU Saint-Louis, Paris (France); Université Denis Diderot, Sorbonne Paris Cité Paris, Paris (France); Casetti, Luana [Institut Cochin INSERM U1016, Paris (France); François, Jean-Hugues; Capron, Claude [Institut Cochin INSERM U1016, Paris (France); Laboratoire d' Hématologie, Hôpital Ambroise Paré, Boulogne (France); Université de Versailles Saint-Quentin en Yvelynes, Versailles (France); Pillet, Sylvie [Laboratoire de Bactériologie-Virologie-Hygiène, CHU de Saint-Etienne, Saint-Etienne (France); Université de Lyon et Université de Saint-Etienne, Jean Monnet, GIMAP EA3064, F-42023 Saint-Etienne, Lyon (France)

    2013-09-15

    The role of oxygen tension level is a well-known phenomenon that has been studied in oncology and radiotherapy since about 60 years. Oxygen tension may inhibit or stimulate propagation of viruses in vitro as well as in vivo. In turn modulating oxygen metabolism may constitute a novel approach to treat viral infections as an adjuvant therapy. The major transcription factor which regulates oxygen tension level is hypoxia-inducible factor-1 alpha (HIF-1α). Down-regulating the expression of HIF-1α is a possible method in the treatment of chronic viral infection such as human immunodeficiency virus infection, chronic hepatitis B and C viral infections and Kaposi sarcoma in addition to classic chemotherapy. The aim of this review is to supply an updating concerning the influence of oxygen tension level in human viral infections and to evoke possible new therapeutic strategies regarding this environmental condition. - Highlights: • Oxygen tension level regulates viral replication in vitro and possibly in vivo. • Hypoxia-inducible factor 1 (HIF-1α) is the principal factor involved in Oxygen tension level. • HIF-1α upregulates gene expression for example of HIV, JC and Kaposi sarcoma viruses. • In addition to classical chemotherapy inhibition of HIF-1α may constitute a new track to treat human viral infections.

  9. Lower leg electrical impedance after distal bypass surgery

    DEFF Research Database (Denmark)

    Belanger, G K; Bolbjerg, M L; Heegaard, N H

    1998-01-01

    Electrical impedance was determined in 13 patients following distal bypass surgery to evaluate lower leg oedema as reflected by its circumference. Tissue injury was assessed by the plasma concentration of muscle enzymes. After surgery, the volume of the control lower leg increased from 1250 (816...... to be a useful method for the evaluation of lower leg oedema after distal bypass surgery....

  10. Protection against high intravascular pressure in giraffe legs

    DEFF Research Database (Denmark)

    Petersen, Karin K.; Hørlyck, Arne; Østergaard, Kristine H.

    2013-01-01

    The high blood pressure in giraffe leg arteries renders giraffes vulnerable to edema. We investigated in 11 giraffes whether large and small arteries in the legs and the tight fascia protect leg capillaries. Ultrasound imaging of foreleg arteries in anesthetized giraffes and ex vivo examination...

  11. Evaluation of the accuracy of a veterinary dynamometric wire tensioner.

    Science.gov (United States)

    Gauthier, C M; McGilvray, K; Myrick, S; Duerr, F; Palmer, R

    2015-01-01

    The purpose of this study was to determine the accuracy of a commonly used veterinary wire tensioner. Wire tension was measured using a load cell after each of five tensioners were used to tension each of six wires to the 66, 84, and 118 mm ring settings in an adjustable custom testing fixture. Each tensioner then experienced simulated aging and testing was repeated. Percentage error was calculated for each ring size, before and after tensioner aging. Measured tension values were compared to manufacturer reported tension values for each ring size using a one-sample two-way t-test; p tension values were significantly lower for 66 mm and 84 mm rings and significantly higher for 118 mm rings, before and after simulated aging. Mean wire tension values did not significantly differ between individual wire tensioners. The tensioners tested achieved significantly different wire tension values than those reported by the manufacturer. This discrepancy could lead to under-tensioning and allowing excessive movement at a fracture site or over-tensioning, leading to wire breakage. We recommend tensioning wires at least to the recommended line on the device for 66 mm and 84 mm rings and at most to the recommended line for 118 mm rings. Further studies are needed to evaluate other veterinary wire tensioners and to develop a calibration method for these devices in practice.

  12. The restless legs syndrome (Ekbom's syndrome)

    African Journals Online (AJOL)

    1983-04-30

    Apr 30, 1983 ... tendency to move the limbs, pain in the distribution of the paraesthesiae, and ... walk; (iiz) insomnia secondary to the above;. (iv) pain with the same distribution as the paraesthesiae; and (v) anxiety, tension or mild depression. Paraesthesiae or ... 600 patients with Parkinson's disease6. The pathogenesis ...

  13. Continuous Platform Development

    DEFF Research Database (Denmark)

    Nielsen, Ole Fiil

    low risks and investments but also with relatively fuzzy results. When looking for new platform projects, it is important to make sure that the company and market is ready for the introduction of platforms, and to make sure that people from marketing and sales, product development, and downstream...... departments are all consulted. Platform ideas originate primarily from experienced workers, managers, or platform thinkers. Platform projects are presented regularly for future users and decision makers in structured presentations consisting of both quantitative estimates of costs and benefits and qualitative...

  14. Immediate effects of the trunk stabilizing exercise on static balance parameters in double-leg and one-leg stances

    OpenAIRE

    Kim, Jwa-jun; Park, Se-yeon

    2016-01-01

    [Purpose] The purpose of this study was to evaluate the immediate effect of stabilizing exercise using the PNF technique on standing balance in one-leg and double-leg stances. [Subjects and Methods] The present study recruited 34 healthy participants from a local university. The Participants performed four balance tests (double-leg stance with and without vision, one-leg stance with and without vision), before and after exercise. The exercise consisted of exercises performed using PNF techniq...

  15. Cross-Platform Technologies

    Directory of Open Access Journals (Sweden)

    Maria Cristina ENACHE

    2017-04-01

    Full Text Available Cross-platform - a concept becoming increasingly used in recent years especially in the development of mobile apps, but this consistently over time and in the development of conventional desktop applications. The notion of cross-platform software (multi-platform or platform-independent refers to a software application that can run on more than one operating system or computing architecture. Thus, a cross-platform application can operate independent of software or hardware platform on which it is execute. As a generic definition presents a wide range of meanings for purposes of this paper we individualize this definition as follows: we will reduce the horizon of meaning and we use functionally following definition: a cross-platform application is a software application that can run on more than one operating system (desktop or mobile identical or in a similar way.

  16. Product Platform Modeling

    DEFF Research Database (Denmark)

    Pedersen, Rasmus

    as important assets in a product platform, yet activities, working patterns, processes and knowledge can also be reused in a platform approach. Encapsulation is seen as a process in which the different elements of a platform are grouped into well defined and self-contained units which are decoupled from each......This PhD thesis has the title Product Platform Modelling. The thesis is about product platforms and visual product platform modelling. Product platforms have gained an increasing attention in industry and academia in the past decade. The reasons are many, yet the increasing globalisation...... and the change in the global economy seem to be major factors. Manufacturing companies have experienced an intensifying competition and many companies face increasing demands for reductions in costs and lead times in development and production. At the same time many customers have raised their demands...

  17. Dynamically tensioned ACL functional knee braces reduce ACL and meniscal strain.

    Science.gov (United States)

    Tomescu, Sebastian; Bakker, Ryan; Wasserstein, David; Kalra, Mayank; Nicholls, Micah; Whyne, Cari; Chandrashekar, Naveen

    2017-11-29

    The effectiveness of ACL functional knee braces to reduce meniscal and ACL strain after ACL injury or reconstruction is not well understood. A new dynamic knee tensioning brace system has been designed to apply an active stabilizing force to the knee. The ability of this system to reduce tissue strains is unknown. The purpose of this study was to test the ability of the dynamically tensioned brace to reduce strain in both the ACL and meniscus during rehabilitation activities. A combined in vivo/in silico/in vitro method was used to study three activities: gait, double leg squat, and single leg squat. Muscle forces and kinematics for each activity were derived through in vivo motion capture and applied to seven cadaveric knee specimens fitted with custom braces. Medial meniscal strain and ACL strain were measured in ACL intact, deficient and reconstructed conditions. The brace lowered peak and average meniscal strain in ACL deficient knees (P < 0.05) by an average of 1.7%. The brace was also found to lower meniscal strain in reconstructed knees (1.1%) and lower ACL strain in ACL intact (1.3%) and reconstructed knees (1.4%) (P < 0.05). This study supports the use of a brace equipped with a dynamic tensioning system to lower meniscal strain in ACL-deficient knees. Its use may help decrease the risk of subsequent meniscal tears in chronic ACL deficiency or delayed reconstruction. In ACL-intact and reconstructed knees, the brace may be beneficial in injury prophylaxis or in protecting the ACL graft following reconstruction. These results will aid clinicians make informed recommendations for functional brace use in patients with unstable knees. II.

  18. Multi-leg heat pipe evaporator

    Science.gov (United States)

    Alario, J. P.; Haslett, R. A.

    1986-04-01

    A multileg heat pipe evaporator facilitates the use and application of a monogroove heat pipe by providing an evaporation section which is compact in area and structurally more compatible with certain heat exchangers or heat input apparatus. The evaporation section of a monogroove heat pipe is formed by a series of parallel legs having a liquid and a vapor channel and a communicating capillary slot therebetween. The liquid and vapor channels and interconnecting capillary slots of the evaporating section are connected to the condensing section of the heat pipe by a manifold connecting liquid and vapor channels of the parallel evaporation section legs with the corresponding liquid and vapor channels of the condensing section.

  19. Leg pain in the running athlete.

    Science.gov (United States)

    Pell, Richard F; Khanuja, Harpal S; Cooley, G Robert

    2004-01-01

    Leg pain is a common complaint among recreational and professional athletes who compete in running sports. Evaluation of the individual with intermittent or constant leg pain should be well organized and inclusive. Duration of the pain, its relation to injury, intensity of the pain, and its pattern are important factors. Additionally, changes in the training regimen, its level, intensity, or duration, or in the nature of the routine are critical components of the assessment. Physical examination can help differentiate bony from soft-tissue etiologies. Studies are dictated by the differential diagnosis but include radiographs in almost all patients and selected use of other modalities. These include bone scans and magnetic resonance imaging for medial tibial stress syndrome and stress fractures and intracompartmental pressure measurements for chronic compartment syndrome. Treatment often requires either rest or a change in training regimen. Surgery for conditions such as chronic compartment syndrome frequently allows a return to preinjury activities.

  20. Respiratory-related leg movements and their relationship with periodic leg movements during sleep.

    Science.gov (United States)

    Manconi, Mauro; Zavalko, Irina; Bassetti, Claudio L; Colamartino, Elisabetta; Pons, Marco; Ferri, Raffaele

    2014-03-01

    To describe the time structure of leg movements (LM) in obstructive sleep apnea (OSA) syndrome, in order to advance understanding of their clinical significance. Sleep Research Centre, Oasi Institute (IRCCS), Troina, Italy. Sleep laboratory. Eighty-four patients (16 females, 68 males, mean age 55.1 y, range 29-74 y). Respiratory-related leg movements (RRLM) and those unrelated to respiratory events (NRLM) were examined within diagnostic polysomnograms alone and together for their distributions within the sleep period and for their periodicity. Patients with OSA and RRLM exhibited more periodic leg movements in sleep (PLMS), particularly in NREM sleep. A gradual decrease in number of NRLM across the sleep period was observed in patients with RRLM. This pattern was less clear for RRLM. Frequency histograms of intermovement intervals of all LMs in patients with RRLM showed a prominent first peak at 4 sec, and a second peak at approximately 24 sec coincident with that of PLMS occurring in the absence of OSA. A third peak of lowest amplitude was the broadest with a maximum at approximately 42 sec. In patients lacking RRLM, NRLM were evident with a single peak at 2-4 sec. A stepwise linear regression analysis showed that, after controlling for a diagnosis of restless legs syndrome and apnea-hypopnea index, PLMS remained significantly associated with RRLM. The time structure of leg movements occurring in conjunction with respiratory events exhibit features of periodic leg movements in sleep occurring alone, only with a different and longer period. This brings into question the validity, both biologic and clinical, of scoring conventions with their a priori exclusion from consideration as periodic leg movements in sleep.

  1. Leg perforators and leg length: an anatomic study focusing on topography and angiogenesis.

    Science.gov (United States)

    Boriani, Filippo; Bruschi, Stefano; Fraccalvieri, Marco; Cipriani, Riccardo

    2010-07-01

    The highly variable anatomic distribution of lower leg perforators is explored, with a standardization based on leg length. The possibility of a correlation between leg length and number of perforators is investigated. Twenty-two lower limbs of cadavers were utilized for an anatomic study on the leg perforators branching from the three major vascular axes, anterior tibial, posterior tibial, and fibular. The parameters considered were the number of vascular pedicles per each major axis, the caliber, the distance of the fascial hole from the bony landmark (knee joint line), and the route of the vessels (muscular, septal). Arteries taken into account had a caliber of 0.5 mm or greater, with a maximum of 1.7 and a mean of 0.78. The perforators of the anterior tibial artery distribute along the entire length of the leg, but the peak of concentration is between second and third tenth and around the middle tenth. The fibular system provides perforators between the fourth and seventh tenth. The posterior tibial perforators concentrate to the middle third and to the supramalleolar region. A correlation exists between leg length and number of perforating vessels for the tibial vascular systems, possibly due to neoangiogenesis during growth, at the level of the metaphyseal plates. On the contrary no relationship was noticed for the fibular artery, whose perforators concentrate far from the growth cartilages. Some tenths where perforators concentrate are identifiable. Tibial systems have a perforator incidence depending on leg length, which, on the contrary, does not influence the number of fibular perforators. (c) 2010 Wiley-Liss, Inc.

  2. Chronic Leg Ulcers in Drug Abusers

    Directory of Open Access Journals (Sweden)

    Mittal Radha

    2000-01-01

    Full Text Available Four young males with chronic non pitting swelling of lower legs associated with multiple ulcers, scars and pigmentation after parenteral drug abuse were observed in the Dermatovenereology department during last one year. Three of them had active ulcers which healed with withdrawal of offending drug, use of systemic and topical antibiotics and B-complex. All cases were referred to the deaddiction centre. The characteristic clinical features helped in the diagnosis even before history of drug abuse was obtained.

  3. Experimental research on pedestrian lower leg impact

    Science.gov (United States)

    Constantin, B. A.; Iozsa, D. M.; Stan, C.

    2017-10-01

    The present paper is centred on the research of deceleration measured at the level of the lower leg during a pedestrian impact in multiple load cases. Basically, the used methodology for physical test setup is similar to EuroNCAP and European Union regulatory requirements. Due cost reduction reasons, it was not used a pneumatic system in order to launch the lower leg impactor in the direction of the vehicle front-end. During the test it was used an opposite solution, namely the vehicle being in motion, aiming the standstill lower leg impactor. The impactor has similar specifications to those at EU level, i.e. dimensions, materials, and principle of measurement of the deceleration magnitude. Therefore, all the results obtained during the study comply with the requirements of both EU regulation and EuroNCAP. As a limitation, due to unavailability of proper sensors in the equipment of the lower leg impactor, that could provide precise results, the bending angle, the shearing and the detailed data at the level of knee ligaments were not evaluated. The knee joint should be improved for future studies as some bending angles observed during the post processing of several impact video files were too high comparing to other studies. The paper highlights the first pedestrian impact physical test conducted by the author, following an extensive research in the field. Deceleration at the level of pedestrian knee can be substantially improved by providing enough volume between the bumper fascia and the front-end structure and by using pedestrian friendly materials for shock absorbers, such as foams.

  4. The effect of vesicle shape, line tension, and lateral tension on membrane-binding proteins

    Science.gov (United States)

    Hutchison, Jaime B.

    Model membranes allow for the exploration of complex biological phenomena with simple, controllable components. In this thesis we employ model membranes to determine the effect of vesicle properties such as line tension, lateral tension, and shape on membrane-binding proteins. We find that line tension at the boundary between domains in a phase separated vesicle can accumulate model membrane-binding proteins (green fluorescent protein with a histidine tag), and that those proteins can, in turn, alter vesicle shape. These results suggest that domains in biological membranes may enhance the local concentration of membrane-bound proteins and thus alter protein function. We also explore how membrane mechanical and chemical properties alter the function of the N-BAR domain of amphiphysin, a membrane-binding protein implicated in endocytosis. We find that negatively charged lipids are necessary for N-BAR binding to membranes at detectable levels, and that, at least for some lipid species, binding may be cooperative. Measurements of N-BAR binding as a function of vesicle tension reveal that modest membrane tension of around 2 mN/m, corresponding to a strain of around 1%, strongly increases N-BAR binding. We attribute this increase in binding with tension to the insertion of N-BAR's N-terminal amphipathic helix into the membrane which increases the membrane area. We propose that N-BAR, which was previously described as being able to sense membrane curvature, may be sensing strain instead. Measurements of membrane deformation by N-BAR as a function of membrane tension reveal that tension can hinder membrane deformation. Thus, tension may favor N-BAR binding yet suppress membrane deformation/tubulation, which requires work against tension. These results suggest that membrane tension, a parameter that is often not controlled in model membranes but is tightly controlled in biological cells, may be important in regulating protein binding and assembly and, hence, protein

  5. Design Concepts of Emergency Response Robot Platform K-R2D2

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Sun Young; Jeong, Kyungmin [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    From the analysis for various mobile robots competed in DARPA Robotics Challenge, there are some drawbacks in using two or four legs because bipedal locomotion is not yet suitable for maintaining stability and quadrupedal locomotion is difficult to go through narrow aisles. Motivated by the above observations, we propose a K-R2D2 robot platform with three legs arranged in the form of a triangle like as R2-D2 robot which is a fictional robot character in the Star Wars movies. This robot has 3 legs with tracks in each sole of the leg. It is statically stable since there are three contact points to ground. In addition, three legs are also possible to design a structure walking stairs that can expand and contract in the vertical direction. This paper has presented the conceptual design, it is developed on the purpose of quick response instead of emergent workers to the extreme conditions disasters. This robot is emergency response robot platform KR2D2 with three legs, which is statically stable to walk or wheel depending on the terrains and move quickly as possible as on uneven terrain or stairs.

  6. Oxygen tension affects lubricin expression in chondrocytes.

    Science.gov (United States)

    Hatta, Taku; Kishimoto, Koshi N; Okuno, Hiroshi; Itoi, Eiji

    2014-10-01

    We assessed the effects of oxygen tension on lubricin expression in bovine chondrocytes and cartilage explants and a role for hypoxia-inducible transcription factor (HIF)-1α in regulating lubricin expression was investigated using a murine chondroprogenitor cell line, ATDC5, and bovine chondrocytes isolated from superficial and middle/deep zones of femoral cartilage. ATDC5 cells and bovine chondrocytes were cultured in micromass under different oxygen tensions (21%, 5%, and 1%). ATDC5 cells and middle/deep zone chondrocytes that initially had low lubricin expression levels were also cultured with or without transforming growth factor (TGF)-β1. Quantitative reverse transcription (RT)-PCR was used to determine lubricin and chondrogenic marker gene mRNA levels and immunohistochemistry was used to assess lubricin protein expression. Explant cartilage plugs cultured under different oxygen tensions were also subjected to immunohistological analysis for lubricin. HIF-1α gene silencing was achieved by electroporatic transfer into ATDC5 cells. A low oxygen tension reduced lubricin gene expression levels in bovine superficial chondrocytes, TGF-β1-treated middle/deep zone chondrocytes, and TGF-β1-treated ATDC5 cells. Lubricin expression in explant cartilage was also suppressed under hypoxia. HIF-1α gene silencing in ATDC5 cells attenuated the lubricin expression response to the oxygen tension. These results corroborate with previous studies that the oxygen tension regulates lubricin gene expression and suggest that HIF-1α plays an important role in this regulation. The normal distribution of lubricin in articular cartilage may be due to the hypoxic oxygen environment of cartilage as it is an avascular tissue. An oxygen tension gradient may be a key factor for engineering cartilage tissue with a layered morphology.

  7. A novel approach to pipeline tensioner modeling

    Energy Technology Data Exchange (ETDEWEB)

    O' Grady, Robert; Ilie, Daniel; Lane, Michael [MCS Software Division, Galway (Ireland)

    2009-07-01

    As subsea pipeline developments continue to move into deep and ultra-deep water locations, there is an increasing need for the accurate prediction of expected pipeline fatigue life. A significant factor that must be considered as part of this process is the fatigue damage sustained by the pipeline during installation. The magnitude of this installation-related damage is governed by a number of different agents, one of which is the dynamic behavior of the tensioner systems during pipe-laying operations. There are a variety of traditional finite element methods for representing dynamic tensioner behavior. These existing methods, while basic in nature, have been proven to provide adequate forecasts in terms of the dynamic variation in typical installation parameters such as top tension and sagbend/overbend strain. However due to the simplicity of these current approaches, some of them tend to over-estimate the frequency of tensioner pay out/in under dynamic loading. This excessive level of pay out/in motion results in the prediction of additional stress cycles at certain roller beds, which in turn leads to the prediction of unrealistic fatigue damage to the pipeline. This unwarranted fatigue damage then equates to an over-conservative value for the accumulated damage experienced by a pipeline weld during installation, and so leads to a reduction in the estimated fatigue life for the pipeline. This paper describes a novel approach to tensioner modeling which allows for greater control over the velocity of dynamic tensioner pay out/in and so provides a more accurate estimation of fatigue damage experienced by the pipeline during installation. The paper reports on a case study, as outlined in the proceeding section, in which a comparison is made between results from this new tensioner model and from a more conventional approach. The comparison considers typical installation parameters as well as an in-depth look at the predicted fatigue damage for the two methods

  8. Emergency percutaneous needle decompression for tension pneumoperitoneum

    Directory of Open Access Journals (Sweden)

    Körner Markus

    2011-05-01

    Full Text Available Abstract Background Tension pneumoperitoneum as a complication of iatrogenic bowel perforation during endoscopy is a dramatic condition in which intraperitoneal air under pressure causes hemodynamic and ventilatory compromise. Like tension pneumothorax, urgent intervention is required. Immediate surgical decompression though is not always possible due to the limitations of the preclinical management and sometimes to capacity constraints of medical staff and equipment in the clinic. Methods This is a retrospective analysis of cases of pneumoperitoneum and tension pneumoperitoneum due to iatrogenic bowel perforation. All patients admitted to our surgical department between January 2005 and October 2010 were included. Tension pneumoperitoneum was diagnosed in those patients presenting signs of hemodynamic and ventilatory compromise in addition to abdominal distension. Results Between January 2005 and October 2010 eleven patients with iatrogenic bowel perforation were admitted to our surgical department. The mean time between perforation and admission was 36 ± 14 hrs (range 30 min - 130 hrs, between ER admission and begin of the operation 3 hrs and 15 min ± 47 min (range 60 min - 9 hrs. Three out of eleven patients had clinical signs of tension pneumoperitoneum. In those patients emergency percutaneous needle decompression was performed with a 16G venous catheter. This improved significantly the patients' condition (stabilization of vital signs, reducing jugular vein congestion, bridging the time to the start of the operation. Conclusions Hemodynamical and respiratory compromise in addition to abdominal distension shortly after endoscopy are strongly suggestive of tension pneumoperitoneum due to iatrogenic bowel perforation. This is a rare but life threatening condition and it can be managed in a preclinical and clinical setting with emergency percutaneous needle decompression like tension pneumothorax. Emergency percutaneous decompression is no

  9. Restless Legs Syndrome Among the Elderly

    Directory of Open Access Journals (Sweden)

    Pei-Hao Chen

    2009-12-01

    Full Text Available Restless legs syndrome is a sleep and movement disorder that affects 5–15% of the general population, with an increased prevalence among the elderly population. It not only affects quality of life but also increases risk of mortality among older adults. The diagnosis is based on clinical symptoms of the patient by four minimal essential criteria. Restless legs syndrome can be divided into primary or secondary causes. Examination should be performed to rule out potentially treatable illnesses, such as iron deficiency, renal failure or peripheral neuropathy, especially among elderly patients. The initial approach to restless legs syndrome should be nonpharmacologic management, such as good sleep hygiene, regular exercise, cognitive behavioral therapy and avoidance of certain aggravating drugs. An algorithm based on scientific evidence and expert opinion was developed for guidance of treatment. Combination or change of medication can be applied to resistant or difficult cases. Since elderly patients are prone to treatment-related side effects, the best strategy is to start medication cautiously and at the lowest recommended dosage.

  10. A New Diagnostic Clue to Osteomyelitis in Chronic Leg Ulcers.

    Science.gov (United States)

    Schattner, Ami; Dubin, Ina; Gelber, Moshe

    2016-05-01

    Chronic leg ulcers are not infrequently complicated by chronic osteomyelitis, which mandates special treatment but may not be evident on radiography. Inflammatory cytokines may cause reactive thrombocytosis in chronic osteomyelitis. Platelet counts were compared in a group of 24 inpatients with chronic leg ulcers and proven chronic osteomyelitis and 24 inpatients with chronic leg ulcers in whom osteomyelitis was not found. Mean and median platelet counts were significantly higher in the leg ulcer and osteomyelitis group vs the leg ulcer group (P 350 × 10(9)/L, sensitivity was 62.5%, but specificity was 91.7%, with a positive predictive value of 88%. Thrombocytosis in chronic leg ulcers is a new, simple, readily available and inexpensive clue to osteomyelitis in chronic leg ulcers when identified, but its absence cannot rule it out. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. LEG CONQUASATION CAUSED BY PETROL TILLER WITH OPEN LOWER LEG FRACTURE

    Directory of Open Access Journals (Sweden)

    Ivan Golubović

    2014-03-01

    Full Text Available We present a 71-year old patient admitted to Plastic and Reconstructive Surgery Clinic, Clinical Center Niš for the right leg conquasation. The patient was injured accidentally by a petrol tiller. On admission, both thigh and lower leg conquasation was observed with large wound on anteromedial thigh and one on medial side of the lower leg. Soft tissue and bones were covered with dirt and pieces of clothing. The wounds were thoroughly rinsed and dirt was removed followed by detailed debridement. After primary surgical treatment of the wound, open proximal lower leg fracture was stabilized with external skeletal fixation using two nails in the proximal and two nails in the distal fragment. Soft tissue defect was treated by plastic surgeon. The patient was administered anti-tetanus protection, antibiotic treatment and anticoagulant prophylaxis of deep vein thrombosis and pulmonary thromboembolism. Physical therapy was initiated subsequent to successful healing of the soft tissue wounds. External skeletal fixation was removed after three months for infection around the proximal nails and the treatment was contuinued using functional Sarmiento’s plaster imobilization leading to full recovery of open lower leg fracture.

  12. TBK1 duplication is found in normal tension and not in high tension ...

    Indian Academy of Sciences (India)

    Supplementary data: TBK1 duplication is found in normal tension and not in high tension glaucoma patients of Indian origin. Lalit Kaurani, Mansi Vishal, Jharna Ray, Abhijit Sen, Kunal Ray and Arijit Mukhopadhyay. J. Genet. 95, 459–461. Table 1. Intraocular pressure of NTG and HTG patients. Total. Mean IOP. Mean IOP ...

  13. Constant-amplitude tests on plain concrete in uniaxial tension and tension-compression

    NARCIS (Netherlands)

    Cornelissen, H.A.W.

    1984-01-01

    This research report is the continuation of Stevin Laboratory Report No. 5-81-7 "Fatigue of plain concrete in uniaxial tension and in alternating tension-compression" [1], in which test set-up, loading equipment and preliminary results have been described. The present report deals with the total set

  14. Platform switching and bone platform switching.

    Science.gov (United States)

    Carinci, Francesco; Brunelli, Giorgio; Danza, Matteo

    2009-01-01

    Bone platform switching involves an inward bone ring in the coronal part of the implant that is in continuity with the alveolar bone crest. Bone platform switching is obtained by using a dental fixture with a reverse conical neck. A retrospective study was performed to evaluate the effectiveness of conventional vs reverse conical neck implants. In the period between May 2004 and November 2007, 86 patients (55 females and 31 males; median age, 53 years) were operated and 234 implants were inserted: 40 and 194 were conventional vs reverse conical neck implants, respectively. Kaplan-Meier algorithm and Cox regression were used to detect those variables associated with the clinical outcome. No differences in survival and success rates were detected between conventional vs reverse conical neck implants alone or in combination with any of the studied variables. Although bone platform switching leads to several advantages, no statistical difference in alveolar crest resorption is detected in comparison with reverse conical neck implants. We suppose that the proximity of the implant abutment junction to the alveolar crestal bone gives no protection against the microflora contained in the micrograph. Additional studies on larger series and a combination of platform switching and bone platform switching could lead to improved clinical outcomes.

  15. Percutaneous tension band wiring for patellar fractures.

    Science.gov (United States)

    Rathi, Akhilesh; Swamy, M K S; Prasantha, I; Consul, Ashu; Bansal, Abhishek; Bahl, Vibhu

    2012-08-01

    To evaluate outcome of percutaneous tension band wiring for transverse fractures of the patella. 16 men and 7 women aged 27 to 65 (mean, 40) years underwent percutaneous tension band wiring for transverse fractures of the patella with a displacement of >3 mm. Pain, operating time, mobility, functional score, and complications were evaluated. 20 patients underwent successful percutaneous tension band wiring. The remaining 3 patients in whom closed reduction failed underwent open reduction and tension band wiring. The mean operating time was 46 (range, 28-62) minutes. The mean follow-up period was 20 (range, 15-30) months. At the latest follow-up, all patients had regained full extension. The objective score was excellent in 20 patients and good in 3, whereas the subjective score was excellent in 17, good in 5, and fair in one. All patients had radiological union at week 8. One patient had patellofemoral arthritis (secondary to a postoperative articular step). Two patients developed superficial infections, which resolved after antibiotic therapy. Mean thigh muscle wasting was 0.7 (range, 0.4-1) cm. Three patients encountered hardware problems (impingement/irritation of the skin over the knee) necessitating implant removal. Percutaneous tension band wiring is a viable option for transverse fractures of the patella.

  16. Dynamic Effects of Anchor Positional Tolerance on Tension Moored Floating Wind Turbine

    Science.gov (United States)

    Wright, Christopher; Pakrashi, Vikram; Murphy, Jimmy

    2016-09-01

    For water depths greater than 60m floating wind turbines will become the most economical option for generating offshore wind energy. Tension mooring stabilised units are one type of platform being considered by the offshore wind energy industry. The complex mooring arrangement used by this type of platform means that the dynamics are greatly effected by offsets in the positioning of the anchors. This paper examines the issue of tendon anchor position tolerances. The dynamic effects of three positional tolerances are analysed in survival state using the time domain FASTLink. The severe impact of worst case anchor positional offsets on platform and turbine survivability is shown. The worst anchor misposition combinations are highlighted and should be strongly avoided. Novel methods to mitigate this issue are presented.

  17. ADMS Evaluation Platform

    Energy Technology Data Exchange (ETDEWEB)

    2018-01-23

    Deploying an ADMS or looking to optimize its value? NREL offers a low-cost, low-risk evaluation platform for assessing ADMS performance. The National Renewable Energy Laboratory (NREL) has developed a vendor-neutral advanced distribution management system (ADMS) evaluation platform and is expanding its capabilities. The platform uses actual grid-scale hardware, large-scale distribution system models, and advanced visualization to simulate realworld conditions for the most accurate ADMS evaluation and experimentation.

  18. Fatigue in tension perpendicular to the grain

    DEFF Research Database (Denmark)

    Clorius, Christian Odin; Pedersen, Martin Bo Uhre; Hoffmeyer, Preben

    1999-01-01

    Traditinally fatigue resistance is quantified as number of cycles to failure at a given stress level. A previous study by the authors showed that fatigue in compression parallel to the grain is governed partly by duration of load and partly by an effect of loading, i.e. a combination of a creep...... and on dowel type joints with slotted in steel plates. In series of ten, the small specimens are taken to fatigue failure in uniform tension at square wave shaped load cycles at 0.01 Hz and 0.1 Hz. In order to test the predictive validity of the result from the small tension specimens, fatigue experiments...... mechanism and a mechanism connected to damage introduce in the loading sequences. The purpose of the present study is to disentangle the effect of duration of load from the effect of load oscillation in fatigue in tension perpendicular to the grain. Fatigue experiments are made on small specimens...

  19. Fatigue In Tension Perpendicular to the Grain

    DEFF Research Database (Denmark)

    Clorius, Christian Odin; Pedersen, Martin Uhre; Hoffmeyer, Preben

    2004-01-01

    Traditionally fatigue resistance is quantified as number of cycles to failure at a given stress level. A previous study by the authors showed that fatigue in compression parallel to the grain is governed partly by duration of load and partly by an effect of loading, i.e. a combination of a creep...... and on dowel type joints with slotted in steel plates. In series of ten, the small specimens are taken to fatigue failure in uniform tension at square wave shaped load cycles at 0.01 Hz and 0.1 Hz. In arder to test the predictive validity of the result from the small tension specimens, fatigue experiments...... mechanism and a mechanism connected to damage introduced in the loading sequences. The purpose of the present study is to disentangle the effect of duration of load from the effect of load oscillation in fatigue in tension perpendicular to the grain. Fatigue experiments are made on small specimens...

  20. Carbon speciation and surface tension of fog

    Science.gov (United States)

    Capel, P.D.; Gunde, R.; Zurcher, F.; Giger, W.

    1990-01-01

    The speciation of carbon (dissolved/particulate, organic/inorganic) and surface tension of a number of radiation fogs from the urban area of Zurich, Switzerland, were measured. The carbon species were dominated by "dissolved" organic carbon (DOC; i.e., the fraction that passes through a filter), which was typically present at levels of 40-200 mg/L. Less than 10% of the DOC was identified as specific individual organic compounds. Particulate organic carbon (POC) accounted for 26-41% of the mass of the particles, but usually less than 10% of the total organic carbon mass. Inorganic carbon species were relatively minor. The surface tensions of all the measured samples were less than pure water and were correlated with their DOC concentrations. The combination of high DOC and POC and low surface tension suggests a mechanism for the concentration of hydrophobic organic contaminants in the fog droplet, which have been observed by numerous investigators. ?? 1990 American Chemical Society.

  1. Tensions between Teams and Their Leaders

    Directory of Open Access Journals (Sweden)

    J. David Johnson

    2016-10-01

    Full Text Available The intersection of teamwork and leadership results in tensions, dilemmas, and paradoxes for both individuals and for institutions such as simultaneously empowering individuals at the same time it frustrates them when our naive, cultural understanding of leadership centralizes power and values leaders who can impose their will and vision on others. Perhaps the fundamental paradox of teamwork and leadership is that the more leadership is focused on an individual the less likely a team’s potential will be realized. Six specific domains where tensions arise are: at team boundaries; culture; who is in charge, rationality/cognition; diversity; and collaborations. Three approaches - clarifying different levels of analysis, temporal factors, and overarching concepts - to resolving tensions are discussed. New conceptions of leadership and the importance of the larger cultural frame within which they are embedded are needed for the management of technology and innovation.

  2. Surface tension-driven convection phenomena

    Science.gov (United States)

    Mann, J. A., Jr.

    1980-01-01

    The techniques for measuring surface tension-driven flow are reported. In addition to the fairly standard crossed beam LDV method, methods using ripplon scattering which do not require seeding of the fluid were developed. These methods can be used to determine thermophysical properties of the surface, such as surface tension, viscosity, and local temperature. This technique was utilized to observe the change in surface tension associated with the nematic to isotropic phase transition of para-azoxydianisole at 134 C. The ripplon scattering methods become difficult for surface velocities below 1 mm/sec because of the overlapping spectra. Careful analysis procedures could extend this to smaller flows, but the more conventional LDV techniques with seeded flows are the method of choice for slow flows.

  3. Immobilization tests and periodic leg movements in sleep for the diagnosis of restless leg syndrome.

    Science.gov (United States)

    Montplaisir, J; Boucher, S; Nicolas, A; Lesperance, P; Gosselin, A; Rompré, P; Lavigne, G

    1998-03-01

    Patients with restless leg syndrome (RLS) complain of motor restlessness, usually occurring while they rest in the evening. Two immobilization tests have been described to assess leg restlessness in these patients. In the first test, the patient sits in bed with his or her legs outstretched while electromyograms are recorded from right and left anterior tibialis muscles for an hour (Suggested Immobilization Test [SIT]); in the second test, the legs are immobilized in a stretcher (Forced Immobilization Test [FIT]). In the current study, the SIT and the FIT were compared in patients with RLS and normal control subjects matched for age and sex. More leg movements were seen in patients than in controls during immobilization tests, especially the SIT. These movements were periodic, occurring at a frequency of approximately one every 12 seconds. The SIT (index > 40) was found to discriminate between RLS and control subjects better than the FIT (index > 25). Patients were also recorded during two consecutive nights to measure periodic leg movements in sleep (PLMS). A SIT index greater than 40 and a PLMS index greater than 11 (highest PLMS index of 2 consecutive nights) were found to discriminate patients with RLS from control subjects with similar power. With each of these two measures, the clinical diagnosis was correctly predicted in 81% of patients and 81% of the control subjects. The SIT has several advantages over the measure of the PLMS index; it does not require an all-night polygraphic recording and can be administered several times a day to measure circadian fluctuation of motor restlessness.

  4. The pants too short, the leg too long: leg length inequality after THA.

    Science.gov (United States)

    Rubash, Harry E; Parvataneni, Hari K

    2007-09-01

    It is critical to develop and use a consistent, systematic and reproducible approach to, perioperatively, evaluate leg length discrepancy in patients undergoing THA. Careful preoperative planning is critical but does not preclude the need for intraoperative assessment once trial components and final components are implanted. Newer techniques such as digital templating and image-guided surgery may provide more accurate techniques, although this has not been proven. Most importantly, careful preoperative planning, intraoperative measurement, and attention to detail will avoid major leg length discrepancies in the majority of patients.

  5. A continuum method for modeling surface tension

    Science.gov (United States)

    Brackbill, J. U.; Kothe, D. B.; Zemach, C.

    1992-01-01

    In the novel method presented for modeling the effects of surface tension on fluid motion, the interfaces between fluids with different, color-represented properties are finite-thickness transition regions across which the color varies continuously. A force density proportional to the surface curvature of constant color is defined at each point in the transition region; this force-density is normalized in such a way that the conventional description of surface tension on an interface is recovered when the ratio of local transition-reion thickness to local curvature radius approaches zero. The properties of the method are illustrated by computational results for 2D flows.

  6. Leg stiffness of sprinters using running-specific prostheses

    Science.gov (United States)

    McGowan, Craig P.; Grabowski, Alena M.; McDermott, William J.; Herr, Hugh M.; Kram, Rodger

    2012-01-01

    Running-specific prostheses (RSF) are designed to replicate the spring-like nature of biological legs (bioL) during running. However, it is not clear how these devices affect whole leg stiffness characteristics or running dynamics over a range of speeds. We used a simple spring–mass model to examine running mechanics across a range of speeds, in unilateral and bilateral transtibial amputees and performance-matched controls. We found significant differences between the affected leg (AL) of unilateral amputees and both ALs of bilateral amputees compared with the bioL of non-amputees for nearly every variable measured. Leg stiffness remained constant or increased with speed in bioL, but decreased with speed in legs with RSPs. The decrease in leg stiffness in legs with RSPs was mainly owing to a combination of lower peak ground reaction forces and increased leg compression with increasing speeds. Leg stiffness is an important parameter affecting contact time and the force exerted on the ground. It is likely that the fixed stiffness of the prosthesis coupled with differences in the limb posture required to run with the prosthesis limits the ability to modulate whole leg stiffness and the ability to apply high vertical ground reaction forces during sprinting. PMID:22337629

  7. Loading and performance of the support leg in kicking.

    Science.gov (United States)

    Ball, Kevin

    2013-09-01

    The punt kick is important in many football codes and support leg kinematics and ground reaction forces have been implicated in injury and performance in kicking. To evaluate ground reaction forces and support leg kinematics in the punt kick. Cross sectional study. Seven elite Australian football players performed maximal kicks into a net using both the preferred and non-preferred legs. A force plate measured ground reaction forces and an optical motion capture system (200Hz) collected kinematic data during the stance phase of the kick. Preferred and non-preferred legs were compared and performance was evaluated by correlating parameters with foot speed at ball contact. Vertical forces were larger than running at a similar speed but did not reach levels that might be considered an injury risk. Braking forces were directed solely posteriorly, as for soccer kicks, but lateral force patterns varied with some players experiencing greater forces medially and others laterally. A more extended support leg, larger peak vertical and braking force during the stance phase and a shorter stance contact time was associated with larger kick leg foot speed at ball contact. No difference existed between the preferred and non-preferred legs for ground reaction forces or support leg mechanics. To punt kick longer, a straighter support leg, less time on the ground and stronger braking should be encouraged. Conditioning the support leg to provide stronger braking potential is recommended. Copyright © 2012 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  8. On the Biomimetic Design of Agile-Robot Legs

    Science.gov (United States)

    Garcia, Elena; Arevalo, Juan Carlos; Muñoz, Gustavo; Gonzalez-de-Santos, Pablo

    2011-01-01

    The development of functional legged robots has encountered its limits in human-made actuation technology. This paper describes research on the biomimetic design of legs for agile quadrupeds. A biomimetic leg concept that extracts key principles from horse legs which are responsible for the agile and powerful locomotion of these animals is presented. The proposed biomimetic leg model defines the effective leg length, leg kinematics, limb mass distribution, actuator power, and elastic energy recovery as determinants of agile locomotion, and values for these five key elements are given. The transfer of the extracted principles to technological instantiations is analyzed in detail, considering the availability of current materials, structures and actuators. A real leg prototype has been developed following the biomimetic leg concept proposed. The actuation system is based on the hybrid use of series elasticity and magneto-rheological dampers which provides variable compliance for natural motion. From the experimental evaluation of this prototype, conclusions on the current technological barriers to achieve real functional legged robots to walk dynamically in agile locomotion are presented. PMID:22247667

  9. Leg stiffness and sprint ability in amputee sprinters.

    Science.gov (United States)

    Hobara, Hiroaki; Tominaga, Shuichi; Umezawa, Shingo; Iwashita, Koudai; Okino, Atsuo; Saito, Taku; Usui, Fumio; Ogata, Toru

    2012-09-01

    Understanding leg stiffness (K (leg)) in amputee sprinters is important for the evaluation of their sprint ability and development of running-specific prostheses (RSP). To investigate K (leg) during hopping in amputee sprinters. Cross-sectional study. Seven transtibial (TT) and seven transfemoral (TF) amputee sprinters, as well as seven non-active able-bodied subjects, performed one-legged hopping matching metronome beats at 2.2 Hz. Amputees hopped on their sound limb whereas able-bodied (AB) subjects hopped on their dominant limb. Using a spring-mass model, K (leg) was calculated from the subjects' body mass, ground contact and flight times. Both TT and TF sprinters demonstrated significantly higher K (leg) than AB subjects. K (leg) during hopping on the sound leg significantly correlated with personal records attained in a 100-m sprint in both TT (r = -0.757) and TF sprinters (r = -0.855). The results of the present study suggest that amputee sprinters have a greater K (leg) during hopping than inactive non-amputees, and that their sprint ability can be predicted from the K (leg) during hopping at 2.2 Hz on the sound limb.

  10. Leg stiffness of sprinters using running-specific prostheses.

    Science.gov (United States)

    McGowan, Craig P; Grabowski, Alena M; McDermott, William J; Herr, Hugh M; Kram, Rodger

    2012-08-07

    Running-specific prostheses (RSF) are designed to replicate the spring-like nature of biological legs (bioL) during running. However, it is not clear how these devices affect whole leg stiffness characteristics or running dynamics over a range of speeds. We used a simple spring-mass model to examine running mechanics across a range of speeds, in unilateral and bilateral transtibial amputees and performance-matched controls. We found significant differences between the affected leg (AL) of unilateral amputees and both ALs of bilateral amputees compared with the bioL of non-amputees for nearly every variable measured. Leg stiffness remained constant or increased with speed in bioL, but decreased with speed in legs with RSPs. The decrease in leg stiffness in legs with RSPs was mainly owing to a combination of lower peak ground reaction forces and increased leg compression with increasing speeds. Leg stiffness is an important parameter affecting contact time and the force exerted on the ground. It is likely that the fixed stiffness of the prosthesis coupled with differences in the limb posture required to run with the prosthesis limits the ability to modulate whole leg stiffness and the ability to apply high vertical ground reaction forces during sprinting.

  11. Robust and efficient walking with spring-like legs

    Energy Technology Data Exchange (ETDEWEB)

    Rummel, J; Blum, Y; Seyfarth, A, E-mail: juergen.rummel@uni-jena.d, E-mail: andre.seyfarth@uni-jena.d [Lauflabor Locomotion Laboratory, University of Jena, Dornburger Strasse 23, 07743 Jena (Germany)

    2010-12-15

    The development of bipedal walking robots is inspired by human walking. A way of implementing walking could be performed by mimicking human leg dynamics. A fundamental model, representing human leg dynamics during walking and running, is the bipedal spring-mass model which is the basis for this paper. The aim of this study is the identification of leg parameters leading to a compromise between robustness and energy efficiency in walking. It is found that, compared to asymmetric walking, symmetric walking with flatter angles of attack reveals such a compromise. With increasing leg stiffness, energy efficiency increases continuously. However, robustness is the maximum at moderate leg stiffness and decreases slightly with increasing stiffness. Hence, an adjustable leg compliance would be preferred, which is adaptable to the environment. If the ground is even, a high leg stiffness leads to energy efficient walking. However, if external perturbations are expected, e.g. when the robot walks on uneven terrain, the leg should be softer and the angle of attack flatter. In the case of underactuated robots with constant physical springs, the leg stiffness should be larger than k-tilde = 14 in order to use the most robust gait. Soft legs, however, lack in both robustness and efficiency.

  12. Robust and efficient walking with spring-like legs.

    Science.gov (United States)

    Rummel, J; Blum, Y; Seyfarth, A

    2010-12-01

    The development of bipedal walking robots is inspired by human walking. A way of implementing walking could be performed by mimicking human leg dynamics. A fundamental model, representing human leg dynamics during walking and running, is the bipedal spring-mass model which is the basis for this paper. The aim of this study is the identification of leg parameters leading to a compromise between robustness and energy efficiency in walking. It is found that, compared to asymmetric walking, symmetric walking with flatter angles of attack reveals such a compromise. With increasing leg stiffness, energy efficiency increases continuously. However, robustness is the maximum at moderate leg stiffness and decreases slightly with increasing stiffness. Hence, an adjustable leg compliance would be preferred, which is adaptable to the environment. If the ground is even, a high leg stiffness leads to energy efficient walking. However, if external perturbations are expected, e.g. when the robot walks on uneven terrain, the leg should be softer and the angle of attack flatter. In the case of underactuated robots with constant physical springs, the leg stiffness should be larger than k = 14 in order to use the most robust gait. Soft legs, however, lack in both robustness and efficiency.

  13. Probabilistic analysis and fatigue damage assessment of offshore mooring system due to non-Gaussian bimodal tension processes

    Science.gov (United States)

    Chang, Anteng; Li, Huajun; Wang, Shuqing; Du, Junfeng

    2017-08-01

    Both wave-frequency (WF) and low-frequency (LF) components of mooring tension are in principle non-Gaussian due to nonlinearities in the dynamic system. This paper conducts a comprehensive investigation of applicable probability density functions (PDFs) of mooring tension amplitudes used to assess mooring-line fatigue damage via the spectral method. Short-term statistical characteristics of mooring-line tension responses are firstly investigated, in which the discrepancy arising from Gaussian approximation is revealed by comparing kurtosis and skewness coefficients. Several distribution functions based on present analytical spectral methods are selected to express the statistical distribution of the mooring-line tension amplitudes. Results indicate that the Gamma-type distribution and a linear combination of Dirlik and Tovo-Benasciutti formulas are suitable for separate WF and LF mooring tension components. A novel parametric method based on nonlinear transformations and stochastic optimization is then proposed to increase the effectiveness of mooring-line fatigue assessment due to non-Gaussian bimodal tension responses. Using time domain simulation as a benchmark, its accuracy is further validated using a numerical case study of a moored semi-submersible platform.

  14. Studi Pengaruh Gerak Semi-submersible Drilling Rig dengan Variasi Pre-tension Mooring Line terhadap Keamanan Drilling Riser

    Directory of Open Access Journals (Sweden)

    Arda Arda

    2012-09-01

    Full Text Available Analisis terhadap sistem tambat pada anjungan pengeboran semi-submersible drilling rig perlu dilakukan sebelum dilakukannya operasi di lapangan untuk mengetahui perencanaan sistem tambat yang tepat dan aman. Dalam penelitian ini dilakukan analisa perilaku gerak semi-submersible dengan variasi pre-tension mooring line untuk mengetahui berapa besar pre-tension minimal yang harus digunakan agar operasi pengeboran di lingkungan laut Natuna dapat berjalan dengan aman. Variasi pre-tension yang digunakan adalah sebesar 400kN-2000kN dengan penambahan sebesar 400kN. Karakteristik gerakan semi-submersible diprediksi dengan menghitung RAO free floating dengan pemodelan numerik dalam domain frekuensi. Kemudian dilakukan analisa simulasi sistem lengkap (platform, mooring dan drilling riser dengan pemodelan numerik dalam domain waktu. Hasil yang didapat yakni nilai maksimum tegangan mooring line memenuhi batas kriteria API-RP2SK untuk semua variasi pre-tension dengan safety factor terkecil 2.44. Sudut flex joint drilling riser yang terjadi melewati batas kriteria API-RP16Q pada pre-tension 400kN-800kN yang mencapai 6.20 untuk sudut maksimum dan 4.80 untuk sudut rata-rata. Tegangan von Mises yang terjadi pada drilling riser melebihi kriteria API-RP16Q pada pre-tension 400kN-1200kN karena nilainya mencapai 369 MPa (0.82 yield stress.

  15. The Effect of Single-Leg Stance on Dancer and Control Group Static Balance.

    Science.gov (United States)

    Kilroy, Elisabeth A; Crabtree, Olivia M; Crosby, Brittany; Parker, Amanda; Barfield, William R

    The purpose of this study was to compare kinetic differences of static balance between female dancers (D) with at least seven years of dance experience and female non-dancers (ND) who were typical college students. Participants were tested in single-leg stance. Both the dominant leg (DL) and non-dominant leg (NDL) were tested with the participants shod (S) and barefoot (BF). Kinetic variables (vertical, medio-lateral [ML], antero-posterior [AP] maximum ground reaction forces (GRF), and center of pressure (COP) ML and AP) were measured by a Bertec force platform at 1000 Hz with participants S and BF. Each subject's stance was measured over 3 × 30-second intervals. No significant differences (p≥0.05) existed between groups for height, body mass, or age. Significant differences existed between groups for balance time, AP GRF in both BF and S conditions for both DL and NDL, and ML GRF in BF NDL and S DL and NDL conditions. D and ND in BF and S conditions with DL and NDL static stance demonstrate different AP and ML GRF when balancing over a 30-second time interval. Data may suggest that ND are more prone to lose their balance. Further investigation is warranted to understand whether individuals in the rehabilitative field and athletic populations can use dance therapy for injury prevention and rehabilitation.

  16. [Bow legged adjectives in ancient literature].

    Science.gov (United States)

    Simon, Frantisek; Steger, Florian

    2011-01-01

    This article addresses the issue of capturing the medical entity called 'curved legs' in a terminologically exact way. In so doing, it refers to the long-lasting process of differentiation of exact nuances of meaning in Ancient Greek and Latin. In the chronological perusal of ancient Greek literature, it becomes evident that the various adjectives employed are often vague when looking at non-medical literature. By contrast, in the Hippocratic corpus these terms are for the first time annotated with explanations intended to lead to a more precise understanding of the described deformity. Further attempts of differentiation can be found in the writings of Galen, who not only distinguishes between outward and inward curvatures, but also between deformities of the thigh and lower leg as well as between pathological and natural curvatures. Latin literature also provides a series of adjectives that were initially often used in the meaning of 'curved' but it was not until Celsus that these were differentiated with respect to the type and direction of the curvature. When comparing Greek and Latin adjectives, it turns out that though the Latin term blaesus can be traced back etymologically to the Greek word beta lambda alpha iota sigma ó zeta, the meaning of beta lambda alpha iota sigma ó zeta does not fully correspond to that of the Latin word. It is not before the later common transliteration of Greek words that this adjective took on the meaning of beta lambda alpha iota sigma ó zeta; however, this was finally lost again. In summary, the article concludes that exact word meanings in ancient literature are often unclear and precise ascriptions of meanings are inconsistent. In the case of "curved legs," this has led to misunderstandings regarding the respective types and directions of the curvature.

  17. Leg ulcer in lepromatous leprosy - Case report*

    Science.gov (United States)

    Fernandes, Tania Rita Moreno de Oliveira; dos Santos, Talita Suzany Siqueira; Lopes, Ramon Rodrigues de Macedo

    2016-01-01

    In Brazil, leprosy is a widespread infectious and contagious disease. Clinicians and specialists view leprosy broadly as a systemic infection, since, in its manifestations, it mimics many conditions, such as rheumatic, vascular, ENT, neurological and dermatological diseases. There are few studies that characterize the factors associated with ulcers in leprosy. These injuries should be prevented and treated promptly to avoid serious problems like secondary infections, sepsis, carcinomatous degeneration and amputations. We describe a patient with ulcers on his legs, involving late diagnosis of lepromatous leprosy. PMID:27828650

  18. Gabapentin encarbil (Horizant) for restless leg syndrome.

    Science.gov (United States)

    2011-09-05

    Gabapentin enacarbil (Horizant-GlaxoSmithKline), a new extended-release (ER) tablet formulation of gabapentin, has been approved by the FDA for treatment of moderate-to-severe restless legs syndrome (RLS). The immediate-release (IR) formulation of gabapentin (Neurontin,and others), which is approved for treatment of epilepsy and postherpetic neuralgia, has been used for many years to treat RLS. Another ER tablet formulation of gabapentin (Gralise) has been approved by the FDA for treatment of postherpetic neuralgia. © 2011 The Medical Letter, Inc.

  19. Painful legs and moving toes syndrome

    Directory of Open Access Journals (Sweden)

    Qiu-ying Ma

    2015-10-01

    Full Text Available Painful legs and moving toes syndrome (PLMT is a rare movement disorder with low diagnostic rate, which is characterized by lower limb pain with involuntary movements of feet or toes. Etiology and pathogenesis of this disease is still unclear. Patients have different clinical manifestations, so the diagnosis is difficult. Treatment methods for PLMT are numerous, but so far the treatment of this disease is still a major challenge for clinicians. Further research is still needed to guide clinical work. DOI: 10.3969/j.issn.1672-6731.2015.10.013

  20. Platform development supportedby gaming

    DEFF Research Database (Denmark)

    Mikkola, Juliana Hsuan; Hansen, Poul H. Kyvsgård

    2007-01-01

    , possibly increasing the strategic risks for the firm. This paper reports preliminary findings on platform management process at LEGO, a Danish toy company.  Specifically, we report the process of applying games combined with simulations and workshops in the platform development. We also propose a framework...

  1. Determining if wearable sensors affect infant leg movement frequency.

    Science.gov (United States)

    Jiang, Crystal; Lane, Christianne J; Perkins, Emily; Schiesel, Derek; Smith, Beth A

    2017-06-14

    There is interest in using wearable sensors to measure infant leg movement patterns; however, they were not developed for infant use and their presence may adversely affect infant movement production. Their weight may discourage leg movement production, or their presence may annoy an infant and encourage higher rates of leg movement production. Our purpose was to determine whether wearable sensors affected the frequency of infant leg movements produced. We included 10 infants with typical development and 10 infants at risk of developmental delay, between 2 and 10 months' chronological age. After collecting and analyzing video recordings of infants, we found a negligible difference between the numbers of spontaneous leg movements made while infants wore sensors, compared to those without sensors. Wearable sensors have a negligible effect on the frequency of infant leg movement production, supporting their use in infant movement analysis.

  2. Why do arms extract less oxygen than legs during exercise?

    DEFF Research Database (Denmark)

    Calbet, J A L; Holmberg, H-C; Rosdahl, H

    2005-01-01

    % maximal O2 uptake (V(O2)max) and at V(O2)max with different techniques: diagonal stride (combined arm and leg exercise), double poling (predominantly arm exercise), and leg skiing (predominantly leg exercise). The percentage of O2 extraction was always higher for the legs than for the arms. At maximal...... exercise (diagonal stride), the corresponding mean values were 93 and 85% (n = 3; P extraction correlated with the P(O2) value that causes hemoglobin to be 50% saturated (P50: r = 0.93, P extraction was always higher......Hg, respectively. Because conditions for O2 off-loading from the hemoglobin are similar in leg and arm muscles, the observed differences in maximal arm and leg O2 extraction should be attributed to other factors, such as a higher heterogeneity in blood flow distribution, shorter mean transit time, smaller...

  3. Managing Tensions And Forging Creative Synergies Between ...

    African Journals Online (AJOL)

    Managing Tensions And Forging Creative Synergies Between Indigenous And Modern Settlement Planning Concepts And Practices: Lessons For The Design And Planning For ... The article also explores the planning principles, design concepts, standards and norms used in the planning and building of indigenous

  4. Surface Tension Measurements with a Smartphone

    Science.gov (United States)

    Goy, Nicolas-Alexandre; Denis, Zakari; Lavaud, Maxime; Grolleau, Adrian; Dufour, Nicolas; Deblais, Antoine; Delabre, Ulysse

    2017-01-01

    Smartphones are increasingly used in higher education and at university in mechanics, acoustics, and even thermodynamics as they offer a unique way to do simple science experiments. In this article, we show how smartphones can be used in fluid mechanics to measure surface tension of various liquids, which could help students understand the concept…

  5. On Surface Tension for Compact Stars

    Indian Academy of Sciences (India)

    In an earlier analysis it was demonstrated that general relativity gives higher values of surface tension in strange stars with quark matter than neutron stars. We generate the modified Tolman–Oppenheimer–Volkoff equation to incorporate anisotropic matter and use this to show that pressure anisotropy provides for a wide ...

  6. Exact analytical density profiles and surface tension

    Indian Academy of Sciences (India)

    to nonideality, which distinguish electrolyte from nonelectrolyte solutions. An example is provided by the excess surface tension for an air–water interface, which is determined by the excess particle density, and which was first calculated by Onsager and Samaras. Because of the discrepancy between the dielectric constants ...

  7. Measuring the surface tension of soap bubbles

    Science.gov (United States)

    Sorensen, Carl D.

    1992-01-01

    The objectives are for students to gain an understanding of surface tension, to see that pressure inside a small bubble is larger than that inside a large bubble. These concepts can be used to explain the behavior of liquid foams as well as precipitate coarsening and grain growth. Equipment, supplies, and procedures are explained.

  8. Tension band fixation of medial malleolus fractures.

    Science.gov (United States)

    Ostrum, R F; Litsky, A S

    1992-01-01

    A prospective study on tension band fixation of medial malleolus fractures was performed on 30 consecutive patients with 31 fractures from October 1987 until December 1990. All patients had at least a displaced medial malleolus fracture unreduced by closed methods. The fractures were classified into small, medium and large using a modified Lauge-Hansen classification. There were no nonunions or movements of wires postoperatively and only two patients had subjective complaints with reference to the wires that required hardware removal. There was one 2-mm malreduction and one patient with a wound slough and subsequent osteomyelitis. One fragment had 2 mm of displacement after fixation but went on to union. A biomechanical study was undertaken to compare fixation of the medial malleolus with K wires alone, K wires plus a tension band, and two cancellous screws. The tension band fixation provided the greatest resistance to pronation forces: for times stiffer than the two screws and 62% of the intact specimen. Tension band fixation of the medial malleolus is a biomechanically strong and clinically acceptable method of treatment for displaced medial malleolus fractures. This method of fixation may be especially useful for small fragments and in osteoporotic bone.

  9. Mechanotransduction: vinculin provides stability when tension rises

    NARCIS (Netherlands)

    Spanjaard, E.; de Rooij, J.

    2013-01-01

    By beautiful imaging and state-of-the-art experiments, vinculin is established to be a central switch in mechanotransduction at integrin-based focal adhesions. Cycles of tension-regulated vinculin switching control focal adhesion dynamics and signaling to enable polarized cell migration and

  10. Intraoperative Development of Tension Pneumocephalus in a ...

    African Journals Online (AJOL)

    result in intracranial hypertension. This condition, termed. “tension pneumocephalus,” is a neurosurgical emergency and if left untreated may cause rapid neurological deterioration, herniation, and death.[4-6]. Nitrous oxide (N2O), often administered as a component of general anesthesia, has also been implicated in.

  11. Multiple Intelligences: Its Tensions and Possibilities

    Science.gov (United States)

    Eisner, Elliot W.

    2004-01-01

    This article explores the tensions between Howard Gardner's theory of multiple intelligences and current educational policies emphasizing standardized and predictable outcomes. The article situates Gardner's theory within the historical interests among psychometricians in identifying those core processes that constitute human intelligence.…

  12. Focal adhesions, stress fibers and mechanical tension

    Energy Technology Data Exchange (ETDEWEB)

    Burridge, Keith, E-mail: Keith_Burridge@med.unc.edu [Department of Cell Biology and Physiology, and Lineberger Comprehensive Cancer Center, 12-016 Lineberger, CB#7295, University of North Carolina, Chapel Hill, NC (United States); Guilluy, Christophe, E-mail: christophe.guilluy@univ-nantes.fr [Inserm UMR-S1087, CNRS UMR-C6291, L' institut du Thorax, and Université de Nantes, Nantes (France)

    2016-04-10

    Stress fibers and focal adhesions are complex protein arrays that produce, transmit and sense mechanical tension. Evidence accumulated over many years led to the conclusion that mechanical tension generated within stress fibers contributes to the assembly of both stress fibers themselves and their associated focal adhesions. However, several lines of evidence have recently been presented against this model. Here we discuss the evidence for and against the role of mechanical tension in driving the assembly of these structures. We also consider how their assembly is influenced by the rigidity of the substratum to which cells are adhering. Finally, we discuss the recently identified connections between stress fibers and the nucleus, and the roles that these may play, both in cell migration and regulating nuclear function. - Highlights: • The different types of stress fiber and focal adhesion are described. • We discuss the controversy about tension and assembly of these structures. • We describe the different models used to investigate assembly of these structures. • The influence of substratum rigidity is discussed. • Stress fiber connections to the nucleus are reviewed.

  13. Forensic testing of post tensioned concrete girders.

    Science.gov (United States)

    2014-07-01

    Recently, two separate Interstate 15 highway bridges over the 400 South roadway in Orem, Utah were demolished : after 50 years of service. A total of four post-tensioned girders were salvaged from both the north-bound and : south-bound bridge. A seri...

  14. Tension in Chemistry and Its Contents

    Science.gov (United States)

    Hoffmann, Roald

    2015-01-01

    This article makes a case for a positive role of tension in the creative process in chemistry. I begin with an argument that there is an inherent tension in what makes molecules interesting—their positioning along various polar axes. One of these, the age-old differentiation between useful (to society and for personal profit) commercialization and pure understanding of molecules and their reactions is characteristic. The question of whether there are any bad molecules then leads me to ethical concerns in chemistry, and a particular working out of these in interactions of chemists in the Middle East. An analysis is made of the special tensions involved in publishing, especially in citation ethics; chemists publish a lot, so this is situation ethics worked out on a daily basis. I then find in the literature of psychology good evidence for the positive value of moderate stress in stimulating creativity. It is obvious that too much tension leads to distress, and there are some institutional aspects of chemistry that do not come out well here. But all in all, the dynamic middle is alive, and it leads to good new science. PMID:26155730

  15. Surface tension of aqueous electrolyte solutions. Thermodynamics

    NARCIS (Netherlands)

    Drzymala, J.; Lyklema, J.

    2012-01-01

    A thermodynamic theory is developed for obtaining the enthalpic and entropic contributions to the surface excess Gibbs energy of electrolyte solutions from the dependence of the surface tension on concentration and temperature. For elaboration, accurate activity coefficients in solution as functions

  16. Normal tension glaucoma and Alzheimer disease

    DEFF Research Database (Denmark)

    Bach-Holm, Daniella; Kessing, Svend Vedel; Mogensen, Ulla

    2012-01-01

    PURPOSE: To investigate whether normal tension glaucoma (NTG) is associated with increased risk of developing dementia/Alzheimer disease (AD). METHODS: A total of 69 patients with NTG were identified in the case note files in the Glaucoma Clinic, University Hospital of Copenhagen (Rigshospitalet...

  17. Tension Tests On Bored Piles In Sand

    DEFF Research Database (Denmark)

    Krabbenhøft, Sven; Clausen, Johan; Damkilde, Lars

    2006-01-01

    The lengths of the bored piles varied from 2 m to 6 m and all were of a diameter of 140 mm. The piles were tested to failure in tension and the load-displacement relations were recorded. The investigation has shown pronounced differences between the load bearing capacities obtained by different...

  18. Association between restless legs syndrome and migraine: a population-based study.

    Science.gov (United States)

    Zanigni, Stefano; Giannini, Giulia; Melotti, Roberto; Pattaro, Cristian; Provini, Federica; Cevoli, Sabina; Facheris, Maurizio F; Cortelli, Pietro; Pramstaller, Peter P

    2014-09-01

    A higher prevalence of restless legs syndrome (RLS) in migraineurs has been reported in clinical samples and in two large-scale clinical trials performed on healthcare workers but general population-based studies on this topic are lacking. The aim of this study was to assess the association between migraine and RLS in an Italian rural adult population-based setting. The presence of migraine and RLS was assessed via a computer-assisted personal interview and self-administered questionnaires according to current diagnostic criteria in 1567 participants of a preliminary phase of an adult population-based study performed in South Tyrol, Italy. Migraineurs had an increased risk of having RLS also after adjustment for confounding factors such as age, sex, major depression, anxiety and sleep quality (odds ratio 1.79; confidence interval 1.00-3.19; P = 0.049). This association was not modified by aura status and possible causes of secondary RLS. RLS was not significantly associated with tension-type headache. Restless legs syndrome and migraine were associated in our rural adult population. This association could be explained by a possible shared pathogenic pathway which would implicate new management strategies of these two disorders. © 2014 The Author(s) European Journal of Neurology © 2014 EAN.

  19. Exploratory experimental investigations on post-tensioned structural glass beams

    DEFF Research Database (Denmark)

    Louter, C.; Nielsen, Jens Henrik; Belis, J.

    2013-01-01

    This paper discusses two projects on post-tensioned glass beams, performed at EPFL and DTU, respectively. In these projects small scale glass beams (length of 1.5m and 1m) are post-tensioned by means of steel threaded rods tensioned at the beam ends. The purpose of post-tensioning glass beams...... is to enhance the initial failure stress of the glass and to obtain ductile (post-breakage) performance. From four-point bending tests on the post-tensioned glass beam specimens it is observed that these goals are reached. From the test results it is concluded that post-tensioning glass beams is a feasible...

  20. Leg ulcers: a new symptom of Blau syndrome?

    Science.gov (United States)

    Dhondt, Veerle; Hofman, Sarah; Dahan, Karin; Beele, Hilde

    2008-01-01

    Blau syndrome is a rare autosomal dominant condition, typically defined by granulomatous polyarthritis, uveitis and skin eruption. Biopsy specimens demonstrate non-caseating granulomas in all lesions. We present a case of Blau syndrome associated with large recalcitrant leg ulcers. Biopsies taken in the leg ulcers of our patient systematically showed granulomas. Although leg ulcers have not previously been described as a part of Blau syndrome, we assume that the ulcerations in this case form part of Blau syndrome.

  1. Vibration transmission characteristics of the legs of freely standing honeybees

    DEFF Research Database (Denmark)

    Rohrseitz, Kristin; Kilpinen, Ole

    1997-01-01

    The leg vibrations of honeybees standing on a vibrating substrate were measured with laser Doppler vibrometry, both in freely standing bees and in bees attached to a holder. In both cases, no resonances were found. In the fixed bee preparation, the legs moved with approximately the same amplitude...... that the subgenual organ is sensitive mainly to vibrations in the direction of the long axis of the leg....

  2. Stable bipedal walking with a swing-leg protraction strategy.

    Science.gov (United States)

    Bhounsule, Pranav A; Zamani, Ali

    2017-01-25

    In bipedal locomotion, swing-leg protraction and retraction refer to the forward and backward motion, respectively, of the swing-leg before touchdown. Past studies have shown that swing-leg retraction strategy can lead to stable walking. We show that swing-leg protraction can also lead to stable walking. We use a simple 2D model of passive dynamic walking but with the addition of an actuator between the legs. We use the actuator to do full correction of the disturbance in a single step (a one-step dead-beat control). Specifically, for a given limit cycle we perturb the velocity at mid-stance. Then, we determine the foot placement strategy that allows the walker to return to the limit cycle in a single step. For a given limit cycle, we find that there is swing-leg protraction at shallow slopes and swing-leg retraction at steep slopes. As the limit cycle speed increases, the swing-leg protraction region increases. On close examination, we observe that the choice of swing-leg strategy is based on two opposing effects that determine the time from mid-stance to touchdown: the walker speed at mid-stance and the adjustment in the step length for one-step dead-beat control. When the walker speed dominates, the swing-leg retracts but when the step length dominates, the swing-leg protracts. This result suggests that swing-leg strategy for stable walking depends on the model parameters, the terrain, and the stability measure used for control. This novel finding has a clear implication in the development of controllers for robots, exoskeletons, and prosthetics and to understand stability in human gaits. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. An Ultralightweight and Living Legged Robot.

    Science.gov (United States)

    Vo Doan, Tat Thang; Tan, Melvin Y W; Bui, Xuan Hien; Sato, Hirotaka

    2018-02-01

    In this study, we describe the most ultralightweight living legged robot to date that makes it a strong candidate for a search and rescue mission. The robot is a living beetle with a wireless electronic backpack stimulator mounted on its thorax. Inheriting from the living insect, the robot employs a compliant body made of soft actuators, rigid exoskeletons, and flexure hinges. Such structure would allow the robot to easily adapt to any complex terrain due to the benefit of soft interface, self-balance, and self-adaptation of the insect without any complex controller. The antenna stimulation enables the robot to perform not only left/right turning but also backward walking and even cessation of walking. We were also able to grade the turning and backward walking speeds by changing the stimulation frequency. The power required to drive the robot is low as the power consumption of the antenna stimulation is in the order of hundreds of microwatts. In contrast to the traditional legged robots, this robot is of low cost, easy to construct, simple to control, and has ultralow power consumption.

  4. Compression Stockings for Treating Venous Leg Ulcers

    Directory of Open Access Journals (Sweden)

    J. P. Benigni

    2013-01-01

    Full Text Available Background. In order to treat venous leg ulcers, it is recommended to use high pressure compression (30–40 mmHg at the ankle. Compression stockings which are not operator dependant could be the best option because of their pressure control. However 30–40 mmHg compression stockings are often hard to put on. Putting two lower pressure compression stockings over each other could be a good therapeutic alternative. Objectives. To compare the in vitro pressures given by the manufacturers of 2 antiulcer kits with the in vivo interface pressures measured in healthy subjects and to evaluate the stiffness and friction indices from those kits based on the interface pressure in order to assess their clinical properties. Material and Methods. Using a Kikuhime pressure device, interface pressure was measured in 12 healthy subjects at the reference point B1. One stiffness index (Static Stiffness Index (SSI and a friction index have been calculated. Results. Mediven Ulcer kit gets the recommended pressures whereas Jobst’s Ulcer Care kit does not for treating a venous leg ulcer. Jobst’s Ulcer Care transmits entirely the pressure in relation to a friction index close to 1. Conclusion. This antiulcer kit study underlines that in vivo and in vitro pressures can be different (Jobst’s Ulcer Care kit and Mediven Ulcer kit. In order not to lose pressure, it is important to take into account the friction index when superimposing two stockings.

  5. Comparison of Plantar Pressure Distribution in Dominant & Non-dominant leg of female Kata and Kumite National Team

    Directory of Open Access Journals (Sweden)

    Elnaz Dizaji

    2016-09-01

    Full Text Available Objective: The aim of this study was to compare the plantar pressure distribution of dominant and non-dominant legs of females who were participated in the kata and kumite national team. Methods: Twelve kumite and 8 kata female athletes of the Karate national team participated in this study. Plantar pressure was measured using emed platform during barefoot walking. After dividing the foot into 10 masks, peak pressure, pressure-time integral, maximum force and force-time integral were calculated. Wilcoxon and U-Mann-Witney tests were used to analyze parameters at a significance level of p ≤ 0.05. Results: In comparison of kata and kumite teams it was found that, kata plantar pressure parameters in Metatarsal-2 (p=0.05 and Metatarsals-3, 4, 5 (p=0.04 were significantly less than those in kumite. Also, in comparison of dominant and non-dominant leg, plantar pressure parameters of dominant leg were less in Metatarsal-2 (p=0.04 and more in Bigtoe (p=0.04 and Toes-3, 4, 5 (p=0.03 than those in the non-dominant leg. Conclusion: Results may be indicative different of natures of the two athletic fields in that Kumite has a higher impact on plantar pressure due to higher mechanical loads. Furthermore, the unequal use of the legs may affect plantar pressure because of leg dominance. Thus, further and more comprehensive studies are necessary to prevent exercise-induced adaptations in professional levels and their treatments.

  6. A pumpless microfluidic device driven by surface tension for pancreatic islet analysis.

    Science.gov (United States)

    Xing, Yuan; Nourmohammadzadeh, Mohammad; Elias, Joshua E Mendoza; Chan, Manwai; Chen, Zequn; McGarrigle, James J; Oberholzer, José; Wang, Yong

    2016-10-01

    We present a novel pumpless microfluidic array driven by surface tension for studying the physiology of pancreatic islets of Langerhans. Efficient fluid flow in the array is achieved by surface tension-generated pressure as a result of inlet and outlet size differences. Flow properties are characterized in numerical simulation and further confirmed by experimental measurements. Using this device, we perform a set of biological assays, which include real-time fluorescent imaging and insulin secretion kinetics for both mouse and human islets. Our results demonstrate that this system not only drastically simplifies previously published experimental protocols for islet study by eliminating the need for external pumps/tubing and reducing the volume of solution consumption, but it also achieves a higher analytical spatiotemporal resolution due to efficient flow exchanges and the extremely small volume of solutions required. Overall, the microfluidic platform presented can be used as a potential powerful tool for understanding islet physiology, antidiabetic drug development, and islet transplantation.

  7. Experiences of leg bag users and emerging design priorities.

    Science.gov (United States)

    Moody, Louise; McCarthy, Avril

    2015-01-01

    The purpose of the study was to explore participants' experiences of urinary incontinence and leg bag use in order to identify priorities for product redesign. Twenty-nine leg bag users and 5 carers and healthcare professionals participated in the study. They were recruited through a UK hospital Trust and a UK-wide charity for people with bladder and bowel control problems. The study employed a descriptive design with qualitative and quantitative elements to determine current experiences with urinary drainage leg bags and identify potential ways to improve their design. Data collection occurred during semistructured face-to-face and telephone semistructured interviews. Thematic analysis revealed that leg bag design and performance influenced users' relationships, confidence, and ability to socialize. The most significant issues related to leg bag use were reliable functioning without leakage, secure positioning, and discretion when worn under clothing. All participants reported having experienced significant urine leakage due to usability issues with the leg bags. Respondents identified a number of design issues with current leg bags that need to be addressed to improve the ease of use and overall experience when using leg bags for containing urinary output. The findings have been used to define design requirements for further development of leg bags and their component parts.

  8. Restless Legs Syndrome -- Self-Tests and Diagnosis

    Science.gov (United States)

    ... Diagnosis Treatment Jet Lag Overview Symptoms & Self Test Treatment Narcolepsy Overview & Facts Symptoms Self-Tests & Diagnosis Treatment Restless Legs Syndrome Overview & Facts Causes & Symptoms Self- ...

  9. A simple force platform.

    Science.gov (United States)

    Bonde-Petersen, F

    1975-01-01

    The force platform consists of a sandwhich of steel, Rockwool and concrete plates about 900 X 700 mm in surface. Four steel rings were bolted to the under side of the steel plate in each corner. Each steel ring was furnished with only one strain gauge, two of which were placed on the outer- respectively on the inner side of each ring. The four strain gauges were connected to a measuring bridge. Before mounting the rings on the steel plate, the sensitivity to pressure of each ring was adjusted in such a way that they were all similar. Because of this the platform responded with a signal which was independent of where a pressure was applied within the surface of the platform. The platform showed a rectilinear response for static forces up to 500 kp with a stable zero value. In response to dynamic forces the platform showed a resononance frequency of about 50 Hz, with a damping factor of 0.15. Calibration of dynamic forces was carried out by calculation of the forces during a vertical jump compared with what would be expected from the time of flight also registered by the platform-measuring-bridge-ink-writer-set-up. The time of flight was significantly higher (11%) than exected from the time-force relations beforetake-off. This was esplained partly by the relatively low damping factor in the system, partly by the subjects not extending their knees at landing on the platform.

  10. Immediate effects of the trunk stabilizing exercise on static balance parameters in double-leg and one-leg stances.

    Science.gov (United States)

    Kim, Jwa-Jun; Park, Se-Yeon

    2016-06-01

    [Purpose] The purpose of this study was to evaluate the immediate effect of stabilizing exercise using the PNF technique on standing balance in one-leg and double-leg stances. [Subjects and Methods] The present study recruited 34 healthy participants from a local university. The Participants performed four balance tests (double-leg stance with and without vision, one-leg stance with and without vision), before and after exercise. The exercise consisted of exercises performed using PNF techniques (stabilizing reversal and rhythmic stabilization), which were applied to facilitate trunk musculature. To examine balance ability, total displacement of the center of pressure was measured during balance tests. [Results] The total anterior-posterior center of pressure displacement was significantly reduced after applying rhythmic stabilization compared before exercise regardless of the balance test conditions. [Conclusion] The present results suggest that trunk stability exercise using rhythmic stabilization could effectively enhance balance ability under one-leg and double-leg conditions.

  11. Necessary Tension in Marine Risers Tension des colonnes montantes en mer

    Directory of Open Access Journals (Sweden)

    Lubinski A.

    2006-11-01

    Full Text Available The tension governing transverse static and dynamic deflections in a riser is not the actual tension but the so-called « effective tension » The concept of effective tension and effective compression is thoroughly explained, and means for calculating effective forces are given. Numerical examples are worked out for risers whose length is between 152 m (520 ft and 920 m (3020 ft. The reciprocal of maximum bending moment of the vicinity of the hall joint is plotted versus the effective tension of the ball joint. Bending moments used were obtained through use of static and dynamic computer programs applied ta a variety of conditions of wave loading, use or non-use of buoyant moterial sleeves, etc. The most important parameters affecting riser performance are the effective La tension régissant les déflections transversales statiques et dynamiques d'une colonne montante n'est pas la tension réelle mais ce qu'on appelle « la tension effective ». Le concept de tension ou de compression effective est expliqué en détail et la façon de calculer les forces effectives est indiquée dans cet article. Des exemples numériques sont développés pour des colonnes montantes de longueur comprise entre 152 m (520 ft et 920 m (3 020 ft. On a tracé la courbe de l'inverse du moment fléchissant en fonction de la tension effective à l'articulation. Les moments fléchissants utilisés ont été calculés par ordinateur en utilisant des programmes dynamiques et statiques pour des conditions variées d'action des vagues, la colonne montante étant ou non munie de manchettes de flottabilité, etc. Les deux paramètres les plus importants qui affectent le bon comportement d'une colonne montante sont la tension effective et la charge latérale.

  12. A comparison of cation sampling in forest soils by tension and tension-free lysimeters

    Science.gov (United States)

    James H. Miller

    1981-01-01

    Field tests conducted in two soils with ceramic cup, ceramic plate, and tension-free lysimeters showed no concentration differences in collected cations (Ca, Mg, K, Na) between cups and plates, except for the hydrogen ion. Mean pH was 0.6 lower in cup collected samples for a sandy loam profile. Tension-free lysimeters of the design tested had persistent contamination...

  13. The vacuum platform

    Science.gov (United States)

    McNab, A.

    2017-10-01

    This paper describes GridPP’s Vacuum Platform for managing virtual machines (VMs), which has been used to run production workloads for WLCG and other HEP experiments. The platform provides a uniform interface between VMs and the sites they run at, whether the site is organised as an Infrastructure-as-a-Service cloud system such as OpenStack, or an Infrastructure-as-a-Client system such as Vac. The paper describes our experience in using this platform, in developing and operating VM lifecycle managers Vac and Vcycle, and in interacting with VMs provided by LHCb, ATLAS, ALICE, CMS, and the GridPP DIRAC service to run production workloads.

  14. Product Platform Replacements

    DEFF Research Database (Denmark)

    Sköld, Martin; Karlsson, Christer

    2012-01-01

    Purpose – It is argued in this article that too little is known about product platforms and how to deal with them from a manager's point of view. Specifically, little information exists regarding when old established platforms are replaced by new generations in R&D and production environments...... to challenge their existing knowledge about platform architectures. Issues on technologies, architectures, components and processes as well as on segments, applications and functions are identified. Practical implications – Practical implications are summarized and discussed in relation to a framework...

  15. Ladder attachment platform

    Science.gov (United States)

    Swygert,; Richard, W [Springfield, SC

    2012-08-28

    A ladder attachment platform is provided that includes a base for attachment to a ladder that has first and second side rails and a plurality of rungs that extend between in a lateral direction. Also included is a user platform for having a user stand thereon that is carried by the base. The user platform may be positioned with respect to the ladder so that it is not located between a first plane that extends through the first side rail and is perpendicular to the lateral direction and a second plane that extends through the second side rail and is perpendicular to the lateral direction.

  16. Static tensioning promotes hamstring tendons force relaxation more reliably than cycling tensioning.

    Science.gov (United States)

    Piedade, Sérgio Rocha; Dal Fabbro, Inácio Maria; Mischan, Martha Maria; Piedade, Cezar; Maffulli, Nicola

    2017-08-01

    Graft elongation might be a major reason for increased anterior laxity after anterior cruciate ligament (ACL) reconstruction. This study analyzed the force relaxation values and their stabilization when single strands of the gracilis and semitendinosus tendons underwent cyclic and static tensioning at 2.5% strain level, and compared the efficiency of static and cyclic tensioning in promoting force relaxation. Eighteen gracilis tendons and 18 semitendinosus tendons from nine male cadavers (mean age: 22.44years) were subjected to 10 in vitro cyclic loads at 2.5% strain level, or to a static load at 2.5% strain level. During cyclic loading, the reduction in force values tended to stabilize after the sixth cyclic load, while, in the case of static loading, this stabilization occurred by the second minute. Comparing static and cyclic loading, the gracilis tendon had similar mechanical responses in both conditions, while the semitendinosus tendon showed greater force relaxation in static compared with cyclic loading. Considering that the semitendinosus tendon is the main component of the hamstring graft, its biomechanical response to loading should guide the tensioning protocol. Therefore, static tensioning seems more effective for promoting force relaxation of the semitendinosus tendon than cyclic tensioning. The gracilis tendon showed a similar mechanical response to either tensioning protocols. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Ballistic movements of jumping legs implemented as variable components of cricket behaviour.

    Science.gov (United States)

    Hustert, R; Baldus, M

    2010-12-01

    Ballistic accelerations of a limb or the whole body require special joint mechanisms in many animals. Specialized joints can be moved by stereotypic or variable motor control during motor patterns with and without ballistic components. As a model of variable motor control, the specialized femur-tibia (knee) joints of cricket (Acheta domesticus) hindlegs were studied during ballistic kicking, jumping and swimming and in non-ballistic walking. In this joint the tendons of the antagonistic flexor and the extensor muscles attach at different distances from the pivot and the opposed lever arms form an angle of 120 deg. A 10:1 ratio of their effective lever arms at full knee flexion helps to prepare for most ballistic extensions: the tension of the extensor can reach its peak while it is restrained by flexor co-contraction. In kicks, preparatory flexion is rapid and the co-contraction terminates just before knee extensions. Therefore, mainly the stored tension of the extensor muscle accelerates the small mass of the tibia. Jumps are prepared with slower extensor-flexor co-contractions that flex both knees simultaneously and then halt to rotate both legs outward to a near horizontal level. From there, catapult extension of both knees accelerates the body, supported by continued high frequency motor activity to their tibia extensor muscles during the ongoing push-off from the substrate. Premature extension of one knee instantly takes load from the lagging leg that extends and catches up, which finally results in a straight jump. In swimming, synchronous ballistic power strokes of both hindlegs drive the tibiae on a ventral-to-posterior trajectory through the water, well coordinated with the swimming patterns of all legs. In walking, running and climbing the steps of the hindlegs range between 45 deg flexion and 125 deg extension and use non-ballistic, alternating activity of knee flexor and extensor muscles. Steep climbing requires longer bursts from the extensor tibiae

  18. Surface and interfacial tension measurement, theory, and applications

    CERN Document Server

    Hartland, Stanley

    2004-01-01

    This edited volume offers complete coverage of the latest theoretical, experimental, and computer-based data as summarized by leading international researchers. It promotes full understanding of the physical phenomena and mechanisms at work in surface and interfacial tensions and gradients, their direct impact on interface shape and movement, and their significance to numerous applications. Assessing methods for the accurate measurement of surface tension, interfacial tension, and contact angles, Surface and Interfacial Tension presents modern simulations of complex interfacial motions, such a

  19. Assessment and reduction of diaphragmatic tension during hiatal hernia repair.

    Science.gov (United States)

    Bradley, Daniel Davila; Louie, Brian E; Farivar, Alexander S; Wilshire, Candice L; Baik, Peter U; Aye, Ralph W

    2015-04-01

    During hiatal hernia repair there are two vectors of tension: axial and radial. An optimal repair minimizes the tension along these vectors. Radial tension is not easily recognized. There are no simple maneuvers like measuring length that facilitate assessment of radial tension. The aims of this project were to: (1) establish a simple intraoperative method to evaluate baseline tension of the diaphragmatic hiatal muscle closure; and, (2) assess if tension is reduced by relaxing maneuvers and if so, to what degree. Diaphragmatic characteristics and tension were assessed during hiatal hernia repair with a tension gage. We compared tension measured after hiatal dissection and after relaxing maneuvers were performed. Sixty-four patients (29 M:35F) underwent laparoscopic hiatal hernia repair. Baseline hiatal width was 2.84 cm and tension 13.6 dag. There was a positive correlation between hiatal width and tension (r = 0.55) but the strength of association was low (r (2) = 0.31). Four different hiatal shapes (slit, teardrop, "D", and oval) were identified and appear to influence tension and the need for relaxing incision. Tension was reduced by 35.8 % after a left pleurotomy (12 patients); by 46.2 % after a right crural relaxing incision (15 patients); and by 56.1 % if both maneuvers were performed (6 patients). Tension on the diaphragmatic hiatus can be measured with a novel device. There was a limited correlation with width of the hiatal opening. Relaxing maneuvers such as a left pleurotomy or a right crural relaxing incision reduced tension. Longer term follow-up will determine whether outcomes are improved by quantifying and reducing radial tension.

  20. Bending Under Tension Test with Direct Friction Measurement

    DEFF Research Database (Denmark)

    Andreasen, Jan Lasson; Olsson, David Dam; Chodnikiewicz, K.

    2006-01-01

    A special Bending-Under-Tension (BUT) transducer has been developed in which friction around the tool radius can be directly measured when drawing a plane sheet strip around a cylindrical tool-pin under constant back tension. The front tension, back tension and torque on the tool-pin are all...... in drawing of stainless steel showing the influence of varying process conditions and the performance of different lubricants....

  1. USA Hire Testing Platform

    Data.gov (United States)

    Office of Personnel Management — The USA Hire Testing Platform delivers tests used in hiring for positions in the Federal Government. To safeguard the integrity of the hiring processes and ensure...

  2. Product Platform Performance

    DEFF Research Database (Denmark)

    Munk, Lone

    , and the subject has gained increased attention in industry and academia the past decade. Literature on platform-based product development is often based on single case studies and it is sparsely verified if expected effects are achieved. This makes it difficult to put forward realistic expectations for companies...... experienced representatives from the different life systems phase systems of the platform products. The effects are estimated and modeled within different scenarios, taking into account financial and real option aspects. The model illustrates and supports estimation and quantification of internal platform...... effects. The model empirically verifies findings in literature and received moderate support from industry in the validation study. The research findings document that product platforms achieve significant internal effects in terms of • reduced development time (often around 25 %), • reduced number...

  3. Platform-based production development

    DEFF Research Database (Denmark)

    Bossen, Jacob; Brunoe, Thomas Ditlev; Nielsen, Kjeld

    2015-01-01

    Platforms as a means for applying modular thinking in product development is relatively well studied, but platforms in the production system has until now not been given much attention. With the emerging concept of platform-based co-development the importance of production platforms is though ind...... indisputable. This paper presents state-of-the-art literature on platform research related to production platforms and investigates gaps in the literature. The paper concludes on findings by proposing future research directions....

  4. Tensions generated in a lateral fabellotibial suture model. Comparison of methods of application of tension, fixation of tension and suture material.

    Science.gov (United States)

    Burton, A F; Horstman, C; Mason, D R

    2015-01-01

    To compare suture tension on a simulated lateral fabellotibial suture model using various methods of application of tension, fixation, and suture materials. Veterinarians constructed simulated lateral fabellotibial suture constructs on a tying stand with a force sensor. Participants used combinations of 45 kg test monofilament nylon, metric 7 braided polyethylene, crimps, crimper, or knots, with their choice of instruments to secure the constructs. The tension in completed constructs was measured and comparisons were made between nylon and polyethylene, the use of crimps compared to knots, and the use of a mechanical distractor compared to hand tightening techniques. A value of p tensions generated ranged from 1.4-171.0N. The median tension of nylon sutures (43.9N ± 44.7N) was significantly greater than polyethylene sutures (9.5 N ± 19.6N). The median tension of constructs secured with crimps (62.8N ± 42.4N) was significantly greater than constructs secured with knots (11.8 N ± 14.8N). The mechanical distractor generated significantly higher median tension (78N ± 50.4N), compared to methods without the device (18.6 N ± 25.1N). There was a large variability in the tension generated in simulated lateral fabellotibial constructs. Veterinarians who used nylon, crimps, and the mechanical tensioner generated constructs with greater tensions.

  5. The development of optimal control laws for orbiting tethered platform systems

    Science.gov (United States)

    Bainum, P. M.

    1986-01-01

    A mathematical model of the open and closed loop in orbit plane dynamics of a space platform-tethered-subsatellite system is developed. The system consists of a rigid platform from which an (assumed massless) tether is deploying (retrieving) a subsatellite from an attachment point which is, in general, offset from the platform's mass center. A Langrangian formulation yields equations describing platform pitch, subsatellite tetherline swing, and varying tether length motions. These equations are linearized about the nominal station keeping motion. Control can be provided by both modulation of the tether tension level and by a momentum type platform-mounted device; system controllability depends on the presence of both control inputs. Stability criteria are developed in terms of the control law gains, the platform inertia ratio, and tether offset parameter. Control law gains are obtained based on linear quadratic regulator techniques. Typical transient responses of both the state and required control effort are presented.

  6. ARM for Platform Application

    Science.gov (United States)

    Patte, Mathieu; Poupat, Jean-Luc; Le Meur, Patrick

    2015-09-01

    The activities described in this paper are part of the CNES R&T “Study of a Cortex-R ARM based architecture” performed by Airbus DS Space System & Electronics in 2014. With the support of CNES, Airbus DS has performed the porting of a representative space application software on an ARM based demonstration platform. This paper presents the platform itself, the activities performed at software level and the first results on this evaluation study.

  7. Floating Ocean Platform

    Science.gov (United States)

    2003-08-15

    STRUCTURAL ENGINEERING-ASCE, 382-390 J. Struct. Eng.-ASCE, 1998 Bisht, RS Jain, AK, Wind and wave induced behaviour of offshore guyed tower ... PRESTRESSED CONCRETE OFFSHORE PLATFORMS, HOUILLE BLANCHE-REVUE INTERNATIONALE DE L EAU, 63-68 Houille Blanche-Rev. Int., 1995 MAURER, WC, RECENT ADVANCES... WIND LOADING OF TOWERS AND OFFSHORE PLATFORMS - DISCUSSION, JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS, 369-372 J. Wind Eng. Ind. Aerodyn

  8. Gabapentin Enacarbil: Pharmacotherapy of Restless Legs Syndrome

    Directory of Open Access Journals (Sweden)

    Ruth Jones

    2010-01-01

    Full Text Available Restless Legs Syndrome (RLS is a prevalent sleep-associated movement disorder greatly affecting patients’ quality of life (QoL. Several drugs can be used to control this condition although the first-line dopamine agents often cause adverse effects. Non-dopaminergic drugs such as oral gabapentin (GBP have been more recently advocated. Despite ameliorating RLS symptoms, GBP's pharmacokinetic limitations restrict its overall effectiveness. A novel specifically designed prodrug, gabapentin enacarbil (GE, has demonstrated successful RLS alleviation with a superior pharmacokinetic profile. This review aims to examine the efficacy and tolerability of both GBP and GE as pharmacotherapy for RLS. Despite some heterogeneity and limitations across research methodologies, GE appears to be a potential RLS therapy superior to GBP and other dopaminergic agents.

  9. Acute Compartment Syndrome of the Leg.

    Science.gov (United States)

    Konda, Sanjit R; Kester, Benjamin S; Fisher, Nina; Behery, Omar A; Crespo, Alexander M; Egol, Kenneth A

    2017-08-01

    Acute compartment syndrome (ACS) is well known among orthopaedic surgeons. The timely diagnosis and management of ACS is crucial to avoiding its sequelae, including renal failure, ischemic contractures, and limb loss. Despite its relative importance, ACS poses a challenge to many residents and clinicians as diagnosis relies largely on clinical judgment. Timely diagnosis and thorough compartment release are essential to optimizing outcomes in ACS. This video highlights a clinical case in which compartment syndrome of the leg was considered, diagnosed, and surgically managed. This video will present the indications for compartment release and a video-guided demonstration of compartment checks using an arterial line transducer, a 4-compartment fasciotomy with 2 incisions, and temporizing vessel loop closure. Compartment syndrome can be a devastating complication of common fractures. It is essential that orthopaedic practitioners understand the immediacy of intervention. We have a responsibility to provide timely, accurate diagnosis along with expedient surgical management.

  10. Series Elastic Actuators for legged robots

    Science.gov (United States)

    Pratt, Jerry E.; Krupp, Benjamin T.

    2004-09-01

    Series Elastic Actuators provide many benefits in force control of robots in unconstrained environments. These benefits include high force fidelity, extremely low impedance, low friction, and good force control bandwidth. Series Elastic Actuators employ a novel mechanical design architecture which goes against the common machine design principal of "stiffer is better." A compliant element is placed between the gear train and driven load to intentionally reduce the stiffness of the actuator. A position sensor measures the deflection, and the force output is accurately calculated using Hooke"s Law (F=Kx). A control loop then servos the actuator to the desired output force. The resulting actuator has inherent shock tolerance, high force fidelity and extremely low impedance. These characteristics are desirable in many applications including legged robots, exoskeletons for human performance amplification, robotic arms, haptic interfaces, and adaptive suspensions. We describe several variations of Series Elastic Actuators that have been developed using both electric and hydraulic components.

  11. Tensions of Teaching Media Literacy in Teacher Education

    Science.gov (United States)

    Ngomba-Westbrook, Nalova Elaine

    2013-01-01

    This study investigates the tensions a teacher educator faces in facilitating a media literacy teacher education course at the university level. Teaching tensions are conceptualized as a three-tier framework. At the first level, tensions may arise in the selection and application of pedagogies associated with critical and new/21st century…

  12. Investigating the tension load of rubber composites by impact ...

    Indian Academy of Sciences (India)

    An increase in the allowable stress when the belt is tensioned was examined during the test, to determine the effect of impact on the tension load. The obtained values of tension load are assessed using basic mathematical and statistical methods. Using the Design of Experiments method, factors that significantly affect the ...

  13. National Community Solar Platform

    Energy Technology Data Exchange (ETDEWEB)

    Rupert, Bart [Clean Energy Collective, Louisville, CO (United States)

    2016-06-30

    This project was created to provide a National Community Solar Platform (NCSP) portal known as Community Solar Hub, that is available to any entity or individual who wants to develop community solar. This has been done by providing a comprehensive portal to make CEC’s solutions, and other proven community solar solutions, externally available for everyone to access – making the process easy through proven platforms to protect subscribers, developers and utilities. The successful completion of this project provides these tools via a web platform and integration APIs, a wide spectrum of community solar projects included in the platform, multiple groups of customers (utilities, EPCs, and advocates) using the platform to develop community solar, and open access to anyone interested in community solar. CEC’s Incubator project includes web-based informational resources, integrated systems for project information and billing systems, and engagement with customers and users by community solar experts. The combined effort externalizes much of Clean Energy Collective’s industry-leading expertise, allowing third parties to develop community solar without duplicating expensive start-up efforts. The availability of this platform creates community solar projects that are cheaper to build and cheaper to participate in, furthering the goals of DOE’s SunShot Initiative. Final SF 425 Final SF 428 Final DOE F 2050.11 Final Report Narrative

  14. Design of a Parachute Canopy Instrumentation Platform

    Science.gov (United States)

    Alshahin, Wahab M.; Daum, Jared S.; Holley, James J.; Litteken, Douglas A.; Vandewalle, Michael T.

    2015-01-01

    This paper discusses the current technology available to design and develop a reliable and compact instrumentation platform for parachute system data collection and command actuation. Wireless communication with a parachute canopy will be an advancement to the state of the art of parachute design, development, and testing. Embedded instrumentation of the parachute canopy will provide reefing line tension, skirt position data, parachute health monitoring, and other telemetry, further validating computer models and giving engineering insight into parachute dynamics for both Earth and Mars entry that is currently unavailable. This will allow for more robust designs which are more optimally designed in terms of structural loading, less susceptible to adverse dynamics, and may eventually pave the way to currently unattainable advanced concepts of operations. The development of this technology has dual use potential for a variety of other applications including inflatable habitats, aerodynamic decelerators, heat shields, and other high stress environments.

  15. Restless legs syndrome in patients on hemodialysis

    Directory of Open Access Journals (Sweden)

    Saleh Mohammad Yaser Salman

    2011-01-01

    Full Text Available Restless legs syndrome (RLS is common among dialysis patients, with a reported prevalence of 6-60%. The prevalence of RLS in Syrian patients on hemodialysis (HD is not known. The purpose of this study is to determine the prevalence of RLS in patients on regular HD, and to find the possible correlation between the presence of RLS and demographic, clinical, and biochemical factors. One hundred and twenty-three patients (male/female = 70/53, mean age = 41.95 ± 15.11 years on HD therapy at the Aleppo University Hospital were enrolled into the study. RLS was diagnosed based on criteria established by the International Restless Legs Syn-drome Study Group (IRLSSG. Data procured were compared between patients with and without RLS. Applying the IRLSSG criteria for the diagnosis, RLS was seen in 20.3% of the study pa-tients. No significant difference in age, gender, and intake of nicotine and caffeine was found between patients with and without the RLS. Similarly, there was no difference between the two groups in the duration of end-stage renal disease (ESRD, the period of dialysis dependence, dialysis adequacy, urea and creatinine levels, and the presence of anemia. The co-morbidities and the use of drugs also did not differ in the two groups. Our study suggests that the high prevalence of RLS among patients on HD requires careful attention and correct diagnosis can lead to better therapy and better quality of life. The pathogenesis of RLS is not clear and further studies are required to identify any possible cause as well as to discover the impact of this syndrome on sleep, quality of life, and possibly other complications such as cardiovasculare disease.

  16. Surface Tension and Fingering of Miscible Interfaces

    Science.gov (United States)

    Abib, Mohammed; Liu, Jian-Bang; Ronney, Paul D.

    1999-01-01

    Experiments on miscible, buoyantly unstable reaction-diffusion fronts and non-reacting displacement fronts in Hele-Shaw cells show a fingering-type instability whose wavelengths (lambda*) are consistent with an interfacial tension (sigma) at the front caused by the change in chemical composition, even though the solutions are miscible in all proportions. In conjunction with the Saffman-Taylor model, the relation sigma = K/tau, where tau is the interface thickness and K approximately equal 4 +/- 2 x 10(exp -6) dyne, enables prediction of our measured values of lambda* as well as results from prior experiments on miscible interfaces. These results indicate that even for miscible fluids, surface tension is generally a more significant factor than diffusion in interfacial stability and flow characteristics.

  17. Cognitive function in tension-type headache.

    Science.gov (United States)

    Waldie, Karen E; Welch, David

    2007-12-01

    The association between tension-type headache and cognitive ability was assessed among 971 members of a longitudinal birth cohort study. Primary headache status was determined at age 32 years according to 2004 International Headache Society criteria, frequent childhood headaches were identified from parent report from ages 7 to 13 years, and data relating to cognitive and academic performance from ages 3 to 32 years were analyzed. Adult study members with tension-type headache did not score worse on any of the cognitive measures relative to headache-free controls or headache-free tinnitus sufferers. Instead, a consistent relation was found between childhood headache (regardless of headache diagnosis in adulthood) and lower scores on most cognitive measures from age 3 years through adolescence (verbal and performance IQ, receptive language, and reading scores). The data indicate that cognitive performance deficits in childhood headache sufferers can probably be attributed to factors stemming from utero or early childhood.

  18. Thermal Analysis of Bending Under Tension Test

    DEFF Research Database (Denmark)

    Ceron, Ermanno; Martins, Paulo A.F.; Bay, Niels

    2014-01-01

    sometimes can cause lubricant film breakdown and galling. In order to replicate the production conditions in bending under tension testing it is thus important to control the tool/workpiece interface temperature. This can be done by pre-heating the tool, but it is essential that the interface temperature......The tribological conditions in deep drawing can be simulated in the Bending Under Tension test to evaluate the performance of new lubricants, tool materials, etc. Deep drawing production with automatic handling runs normally at high rate. This implies considerable heating of the tools, which...... during testing is similar to the one in the production tool. A universal sheet tribo-tester has been developed, which can run multiple tests automatically from coil. This allows emulating the temperature increase as in production. The present work performs finite element analysis of the evolution...

  19. Separation anxiety: Stress, tension and cytokinesis

    Energy Technology Data Exchange (ETDEWEB)

    Mohan, Krithika [Department of Electrical and Computer Engineering, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218 (United States); Iglesias, Pablo A., E-mail: pi@jhu.edu [Department of Electrical and Computer Engineering, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218 (United States); Robinson, Douglas N., E-mail: dnr@jhmi.edu [Department of Cell Biology, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205 (United States)

    2012-07-15

    Cytokinesis, the physical separation of a mother cell into two daughter cells, progresses through a series of well-defined changes in morphology. These changes involve distinct biochemical and mechanical processes. Here, we review the mechanical features of cells during cytokinesis, discussing both the material properties as well as sources of stresses, both active and passive, which lead to the observed changes in morphology. We also describe a mechanosensory feedback control system that regulates protein localization and shape progression during cytokinesis. -- Highlights: Black-Right-Pointing-Pointer Cytokinesis progresses through three distinct mechanical phases. Black-Right-Pointing-Pointer Cortical tension initially resists deformation of mother cell. Black-Right-Pointing-Pointer Late in cytokinesis, cortical tension provides stress, enabling furrow ingression. Black-Right-Pointing-Pointer A mechanosensory feedback control system regulates cytokinesis.

  20. Oral aspirin for treating venous leg ulcers.

    Science.gov (United States)

    de Oliveira Carvalho, Paulo Eduardo; Magolbo, Natiara G; De Aquino, Rebeca F; Weller, Carolina D

    2016-02-18

    Venous leg ulcers (VLUs) or varicose ulcers are the final stage of chronic venous insufficiency (CVI), and are the most common type of leg ulcer. The development of VLUs on ankles and lower legs can occur spontaneously or after minor trauma. The ulcers are often painful and exudative, healing is often protracted and recurrence is common. This cycle of healing and recurrence has a considerable impact on the health and quality of life of individuals, and healthcare and socioeconomic costs. VLUs are a common and costly problem worldwide; prevalence is estimated to be between 1.65% to 1.74% in the western world and is more common in adults aged 65 years and older. The main treatment for a VLU is a firm compression bandage. Compression assists by reducing venous hypertension, enhancing venous return and reducing peripheral oedema. However, studies show that it only has moderate effects on healing, with up to 50% of VLUs unhealed after two years of compression. Non-adherence may be the principal cause of these poor results, but presence of inflammation in people with CVI may be another factor, so a treatment that suppresses inflammation (healing ulcers more quickly) and reduces the frequency of ulcer recurrence (thereby prolonging time between recurrent episodes) would be an invaluable intervention to complement compression treatments. Oral aspirin may have a significant impact on VLU clinical practice worldwide. Evidence for the effectiveness of aspirin on ulcer healing and recurrence in high quality RCTs is currently lacking. To assess the benefits and harms of oral aspirin on the healing and recurrence of venous leg ulcers. In May 2015 we searched: The Cochrane Wounds Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE and EBSCO CINAHL. Additional searches were made in trial registers and reference lists of relevant publications for

  1. In-patient management of leg ulcers | Ohanaka | East African ...

    African Journals Online (AJOL)

    Objective: To review in-patient management of leg ulcers and to compare our experiences with those from other similar centres. Design: A retrospective study. Setting: University of Benin Teaching Hospital, Nigeria. Patients: Forty five patients hospitalisad with leg ulcers. Results: There were 27 male and 18 females (MF 3:2) ...

  2. Common Leg Aliment Of Poultry In Plateau State, Nigeria | Ogbe ...

    African Journals Online (AJOL)

    ... cockerels 17(18.68 %), guinea fowls 15(39.47 %) and ostriches2(5.26 %). Curled toes, mange, Newcastle disease, Mareks disease and Clostridia infections resulting in leg ailments were also observed. Keywords: Leg ailments, Poultry, Implication, Plateau State Animal Research International Vol. 1 (3) 2004 pp. 208-211 ...

  3. Secondary hyperparathyroidism: Uncommon cause of a leg ulcer

    NARCIS (Netherlands)

    van Rijssen, L. B.; Brenninkmeijer, E. E. A.; Nieveen van Dijkum, E. J. M.

    2012-01-01

    Most leg ulcers are vascular based. Only if vascular therapy fails other causes are considered. We report the case of a female with incapacitating leg ulcers caused by a rare condition which was only diagnosed after failing treatment. PRESENTATION OF CASE: The female had an extensive previous

  4. Leg ulcers: a review of their impact on daily life.

    NARCIS (Netherlands)

    Persoon, A.; Heinen, M.M.; Vleuten, C.J.M. van der; Rooij, M.J.M. de; Kerkhof, P.C.M. van de; Achterberg, T. van

    2004-01-01

    BACKGROUND: Current nursing care for leg ulcer patients often focuses on wound care and providing compression therapy. Nurses perceive leg ulcer patients as 'under-served' with regard to problems patients experience in daily life. An overview of patient problems is a first and essential step in the

  5. The recalcitrant venous leg ulcer - A never ending story?

    NARCIS (Netherlands)

    S.W.I. Reeder (Suzan); M.B. Maessen-Visch (Birgitte); S.I. Langendoen; K.P. de Roos; H.A.M. Neumann (Martino)

    2013-01-01

    textabstractIntroduction: In general, four particular causes of recalcitrant venous leg ulcers may be distinguished. These are foot pump insufficiency, chronic venous compartment syndrome and non-re-canalized popliteal vein thrombosis. The fourth cause of recalcitrant venous leg ulcers is

  6. Leg length, sitting height and postmenopausal breast cancer risk

    DEFF Research Database (Denmark)

    Mellemkjær, L; Christensen, J; Frederiksen, K

    2012-01-01

    Tallness has consistently been associated with an increased risk of breast cancer. We investigated the association further by decomposing height into leg length and sitting height.......Tallness has consistently been associated with an increased risk of breast cancer. We investigated the association further by decomposing height into leg length and sitting height....

  7. Ubx regulates differential enlargement and diversification of insect hind legs.

    Directory of Open Access Journals (Sweden)

    Najmus Mahfooz

    2007-09-01

    Full Text Available Differential enlargement of hind (T3 legs represents one of the hallmarks of insect evolution. However, the actual mechanism(s responsible are yet to be determined. To address this issue, we have now studied the molecular basis of T3 leg enlargement in Oncopeltus fasciatus (milkweed bug and Acheta domesticus (house cricket. In Oncopeltus, the T3 tibia displays a moderate increase in size, whereas in Acheta, the T3 femur, tibia, and tarsus are all greatly enlarged. Here, we show that the hox gene Ultrabithorax (Ubx is expressed in the enlarged segments of hind legs. Furthermore, we demonstrate that depletion of Ubx during embryogenesis has a primary effect in T3 legs and causes shortening of leg segments that are enlarged in a wild type. This result shows that Ubx is regulating the differential growth and enlargement of T3 legs in both Oncopeltus and Acheta. The emerging view suggests that Ubx was co-opted for a novel role in regulating leg growth and that the transcriptional modification of its expression may be a universal mechanism for the evolutionary diversification of insect hind legs.

  8. Ubx Regulates Differential Enlargement and Diversification of Insect Hind Legs

    Science.gov (United States)

    Mahfooz, Najmus; Turchyn, Nataliya; Mihajlovic, Michelle; Hrycaj, Steven; Popadić, Aleksandar

    2007-01-01

    Differential enlargement of hind (T3) legs represents one of the hallmarks of insect evolution. However, the actual mechanism(s) responsible are yet to be determined. To address this issue, we have now studied the molecular basis of T3 leg enlargement in Oncopeltus fasciatus (milkweed bug) and Acheta domesticus (house cricket). In Oncopeltus, the T3 tibia displays a moderate increase in size, whereas in Acheta, the T3 femur, tibia, and tarsus are all greatly enlarged. Here, we show that the hox gene Ultrabithorax (Ubx) is expressed in the enlarged segments of hind legs. Furthermore, we demonstrate that depletion of Ubx during embryogenesis has a primary effect in T3 legs and causes shortening of leg segments that are enlarged in a wild type. This result shows that Ubx is regulating the differential growth and enlargement of T3 legs in both Oncopeltus and Acheta. The emerging view suggests that Ubx was co-opted for a novel role in regulating leg growth and that the transcriptional modification of its expression may be a universal mechanism for the evolutionary diversification of insect hind legs. PMID:17848997

  9. Leg power among malaysian netball players | Geok | African Journal ...

    African Journals Online (AJOL)

    The results of the Vertical Jump Test were used to compare the leg power among the subjects in this study and other studies. ... The overall result showed that the Malaysian national netball players had higher leg power compared to other netball players as indicated by Hooper et al., (1995), and Schweigert (1996).

  10. Cloacal impaction with cloacolith in a black-legged seriema ...

    African Journals Online (AJOL)

    Ibrahim Eldaghayes

    2017-12-07

    Dec 7, 2017 ... the first published description of cloacal impaction with cloacolith in black-legged seriema. Case Details. A 5-year-old intact female, captive hatched, black- legged seriema (Chunga burmeisteri) (1,360 kg body weight, body score 3/5) presented for manifesting a behavioral change with a slight decrease in ...

  11. ODYSSEUS autonomous walking robot: The leg/arm design

    Science.gov (United States)

    Bourbakis, N. G.; Maas, M.; Tascillo, A.; Vandewinckel, C.

    1994-01-01

    ODYSSEUS is an autonomous walking robot, which makes use of three wheels and three legs for its movement in the free navigation space. More specifically, it makes use of its autonomous wheels to move around in an environment where the surface is smooth and not uneven. However, in the case that there are small height obstacles, stairs, or small height unevenness in the navigation environment, the robot makes use of both wheels and legs to travel efficiently. In this paper we present the detailed hardware design and the simulated behavior of the extended leg/arm part of the robot, since it plays a very significant role in the robot actions (movements, selection of objects, etc.). In particular, the leg/arm consists of three major parts: The first part is a pipe attached to the robot base with a flexible 3-D joint. This pipe has a rotated bar as an extended part, which terminates in a 3-D flexible joint. The second part of the leg/arm is also a pipe similar to the first. The extended bar of the second part ends at a 2-D joint. The last part of the leg/arm is a clip-hand. It is used for selecting several small weight and size objects, and when it is in a 'closed' mode, it is used as a supporting part of the robot leg. The entire leg/arm part is controlled and synchronized by a microcontroller (68CH11) attached to the robot base.

  12. Surface Tension Demonstration Aboard the ISS

    Science.gov (United States)

    2003-01-01

    Astronaut Donald R. Pettit, Expedition Six NASA ISS science officer, photographed this view of a surface tension demonstration using water that is held in place by a metal loop. The experiment took place in the Destiny laboratory on the International Space Station (ISS). The Expedition Six crew was delivered to the station via the Space Shuttle Orbiter Endeavor STS-113 mission which was launched on November 23, 2002.

  13. Surface tension confined liquid cryogen cooler

    Science.gov (United States)

    Castles, Stephen H.; Schein, Michael E.

    1989-04-01

    A cryogenic cooler is provided for use in craft such as launch, orbital, and space vehicles subject to substantial vibration, changes in orientation, and weightlessness. The cooler contains a small pore, large free volume, low density material to restrain a cryogen through surface tension effects during launch and zero-g operations and maintains instrumentation within the temperature range of 10 to 140 K. The cooler operation is completely passive, with no inherent vibration or power requirements.

  14. A microprocessor based portable bolt tension monitor

    Science.gov (United States)

    Perey, D. F.

    1991-01-01

    A bolt tension monitor (BTM) which uses ultrasonics and a pulsed phase locked loop circuit to measure load-induced acoustic phase shifts which are independent of friction is described. The BTM makes it possible to measure the load in a bolt that was tightened at some time in the past. This capability to recertify a load after-the-fact will help to insure the integrity of a bolted joint.

  15. Conjunctival oxygen tension at high altitude.

    Science.gov (United States)

    Mader, T H; Friedl, K E; Mohr, L C; Bernhard, W N

    1987-01-01

    Transconjunctival oxygen tension (PcjO2) was studied using a hypobaric chamber and during mountaineering excursions. Measurements obtained during acute chamber exposures (15-20 min) at sea level, 1829 m (6,000 ft), 3048 m (10,000 ft), 4267 m (14,000 ft) and return to sea level were (means +/- SEM): 60.1 +/- 2.7, 49.1 +/- 1.8, 38.3 +/- 2.4, 27.4 +/- 1.5, and 61.1 +/- 2.8 mm Hg, respectively (n = 13). The ratio of PcjO2 to arterial blood oxygen tension (PaO2) did not change in a consistent manner between sea level and 4267 m; PcjO2 was 74 +/- 6.9% of PaO2. The 16 subjects participating in the mountaineering phase of the study revealed similar means at sea level and 1829 m (57.4 +/- 2.4 and 46.3 +/- 1.9 mm Hg respectively), but a smaller decrement was observed at 3048 m (43.0 +/- 1.6 mm Hg). The difference between mountain and chamber values may be accounted for by a partial acclimatization to altitude brought about by longer exposure on the mountain excursions. A comparison between PcjO2 and transcutaneous oxygen tension during the chamber study suggests that a greater precision and sensitivity is obtained with measurement of oxygen tension at the conjunctival site. PcjO2 measurement is a non-invasive reflection of PaO2 which is suitable for continuous monitoring during hypoxia studies.

  16. Short-interval leg movements during sleep entail greater cardiac activation than periodic leg movements during sleep in restless legs syndrome patients.

    Science.gov (United States)

    Ferri, Raffaele; Rundo, Francesco; Silvani, Alessandro; Zucconi, Marco; Aricò, Debora; Bruni, Oliviero; Lanuzza, Bartolo; Ferini-Strambi, Luigi; Manconi, Mauro

    2017-10-01

    Periodic leg movements during sleep (PLMS) are sequences of ≥4 motor events with intermovement intervals (IMI) of 10-90 s. PLMS are a supportive diagnostic criterion for restless legs syndrome (RLS) and entail cardiac activation, particularly when associated with arousal. RLS patients also over-express short-interval leg movements during sleep (SILMS), which have IMI sleep. We assessed cardiac activation based on the R-R interval decrease with respect to baseline during NREM sleep without leg movements. We found that the duration of the R-R interval decrease with SILMS doublets was significantly longer than that with PLMS, whereas the maximal decrease in R-R interval was similar. Scoring SILMS in RLS patients may therefore be relevant from a cardiac autonomic perspective. © 2017 European Sleep Research Society.

  17. Laboratory on Legs: An Architecture for Adjustable Morphology with Legged Robots

    Science.gov (United States)

    2012-04-01

    Adjustable Morphology with Legged Robots 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK...Research RHex, but is constructed via an interlock- ing design of flat aluminum pieces, all machined using a waterjet cutter, rather than CNC milling...evenly throughout the body, all mounted on the waterjet cut frame. Through the use of a USB bus as the common communication method within the robot

  18. Relationship between Leg Mass, Leg Composition and Foot Velocity on Kicking Accuracy in Australian Football

    Directory of Open Access Journals (Sweden)

    Nicolas H. Hart, Jodie L. Cochrane, Tania Spiteri, Sophia Nimphius, Robert U. Newton

    2016-06-01

    Full Text Available Kicking a ball accurately over a desired distance to an intended target is arguably the most important skill to acquire in Australian Football. Therefore, understanding the potential mechanisms which underpin kicking accuracy is warranted. The aim of this study was to examine the relationship between leg mass, leg composition and foot velocity on kicking accuracy in Australian Football. Thirty-one Australian Footballers (n = 31; age: 22.1 ± 2.8 years; height: 1.81 ± 0.07 m; weight: 85.1 ± 13.0 kg; BMI: 25.9 ± 3.2 each performed ten drop punt kicks over twenty metres to a player target. Athletes were separated into accurate (n = 15 and inaccurate (n = 16 kicking groups. Leg mass characteristics were assessed using whole body DXA scans. Foot velocity was determined using a ten-camera optoelectronic, three-dimensional motion capture system. Interactions between leg mass and foot velocity evident within accurate kickers only (r = -0.670 to -0.701. Relative lean mass was positively correlated with kicking accuracy (r = 0.631, while no relationship between foot velocity and kicking accuracy was evident in isolation (r = -0.047 to -0.083. Given the evident importance of lean mass, and its interaction with foot velocity for accurate kickers; future research should explore speed-accuracy, impulse-variability, limb co-ordination and foot-ball interaction constructs in kicking using controlled with-in subject studies to examine the effects of resistance training and skill acquisition programs on the development of kicking accuracy.

  19. Knee-ligament injuries associated with leg fractures. Prospective study.

    Science.gov (United States)

    Matić, A; Kasić, M; Hudolin, I

    1992-09-01

    It has been proved in 25-35% of the cases that knee-ligament injuries are associated with fracture of the femoral diaphysis. No such association has been confirmed between leg fractures and knee ligaments. In order to find out if this is a coincidence, a prospective study was conducted on 229 patients who had undergone operations for leg fractures at various locations and of variable intensity. It was established in 41 cases (17.34%) that the leg fracture was associated with knee-ligament injuries, resulting in joint instability. A significantly higher percentage of associated ligament lesions was found in open fractures as opposed to closed leg fractures. The examination was carried out with the patient under general or block anesthesia. On the basis of what was established it is recommended that the knee be examined clinically in all leg osteosynthesis cases.

  20. One-leg standing balance and sports activity.

    Science.gov (United States)

    Hahn, T; Foldspang, A; Vestergaard, E; Ingemann-Hansen, T

    1999-02-01

    The objective of the present cross-sectional study was to estimate one-leg standing balance in athletes and to investigate the relationship with type and amount of sports activity. The study comprised 339 active, competitive, non-pregnant athletes, aged 14-24 years from two sports clubs in the county of Aarhus, Denmark. The athletes answered a questionnaire about occupation and sports activity. One-leg standing balance was measured as the maximum time of one-legged balancing. The mean of the maximum time of one-legged balancing was 29 s (interquartile range 11.25-33.5 s). One-leg standing balance was positively associated with years of participation in basketball and was not associated with sex and age. We conclude that participation in basketball may induce significantly adaptive effects on standing balance.

  1. Validation of a leg movements count and periodic leg movements analysis in a custom polysomnography system.

    Science.gov (United States)

    Stefani, Ambra; Heidbreder, Anna; Hackner, Heinz; Högl, Birgit

    2017-02-23

    Periodic leg movements (PLM) during sleep (PLMS) are considered strongly related to restless legs syndrome (RLS), and are associated with polymorphisms in RLS risk genes. Various software for automatic analysis of PLMS are available, but only few of them have been validated. Aim of this study was to validate a leg movements count and analysis integrated in a commercially available polysomnography (PSG) system against manual scoring. Twenty RLS patients with a PLMS index > 20/h and 20 controls with a PLMS index PLM was performed according to the standard American Academy of Sleep Medicine (AASM) criteria. LM and PLM indices during sleep and wakefulness, the rate of PLMS associated with respiratory events, intermovement interval and periodicity indices were manually and automatically scored. The correlation between manual and computerized scoring was high for all investigated parameters (Spearman correlation coefficients 0.751-0.996, p PLM analysis against the gold standard manual scoring according to AASM criteria. The data demonstrate that the software used in this study has an outstanding performance for computerized LM and PLM scoring, and LM and PLM indices generated with this software can be reliably integrated in the routine PSG report. This automatic analysis is also an excellent tool for research purposes.

  2. LEGS AND TRUNK MUSCLE HYPERTROPHY FOLLOWING WALK TRAINING WITH RESTRICTED LEG MUSCLE BLOOD FLOW

    Directory of Open Access Journals (Sweden)

    Mikako Sakamaki

    2011-06-01

    Full Text Available We examined the effect of walk training combined with blood flow restriction (BFR on the size of blood flow-restricted distal muscles, as well as, on the size of non-restricted muscles in the proximal limb and trunk. Nine men performed walk training with BFR and 8 men performed walk training alone. Training was conducted two times a day, 6 days/wk, for 3 wk using five sets of 2-min bouts (treadmill speed at 50 m/min, with a 1-min rest between bouts. After walk training with BFR, MRI-measured upper (3.8%, P < 0.05 and lower leg (3.2%, P < 0. 05 muscle volume increased significantly, whereas the muscle volume of the gluteus maximus (-0.6% and iliopsoas (1.8% and the muscle CSA of the lumber L4-L5 (-1.0 did not change. There was no significant change in muscle volume in the walk training alone. Our results suggest that the combination of leg muscle blood flow restriction with slow walk training elicits hypertrophy only in the distal blood flow restricted leg muscles. Exercise intensity may be too low during BFR walk training to increase muscle mass in the non- blood flow restricted muscles (gluteus maximus and other trunk muscles.

  3. Detection of Periodic Leg Movements by Machine Learning Methods Using Polysomnographic Parameters Other Than Leg Electromyography

    Directory of Open Access Journals (Sweden)

    İlhan Umut

    2016-01-01

    Full Text Available The number of channels used for polysomnographic recording frequently causes difficulties for patients because of the many cables connected. Also, it increases the risk of having troubles during recording process and increases the storage volume. In this study, it is intended to detect periodic leg movement (PLM in sleep with the use of the channels except leg electromyography (EMG by analysing polysomnography (PSG data with digital signal processing (DSP and machine learning methods. PSG records of 153 patients of different ages and genders with PLM disorder diagnosis were examined retrospectively. A novel software was developed for the analysis of PSG records. The software utilizes the machine learning algorithms, statistical methods, and DSP methods. In order to classify PLM, popular machine learning methods (multilayer perceptron, K-nearest neighbour, and random forests and logistic regression were used. Comparison of classified results showed that while K-nearest neighbour classification algorithm had higher average classification rate (91.87% and lower average classification error value (RMSE = 0.2850, multilayer perceptron algorithm had the lowest average classification rate (83.29% and the highest average classification error value (RMSE = 0.3705. Results showed that PLM can be classified with high accuracy (91.87% without leg EMG record being present.

  4. Surgical Dynamometer to Simultaneously Measure the Tension Forces and the Distance between Wound Edges during the Closure of a Laparotomy.

    Science.gov (United States)

    Roca, Joan; Nogués, Miquel; Villalobos, Rafael; Mías, María Carmen; Comellas, Martí; Gas, Cristina; Olsina, Jorge Juan

    2018-01-11

    The closure of the abdominal wall after making a laparotomy is a major challenge for surgeons, since a significant percentage of closures fail and incisional hernias rise. The suture has to withstand the forces required to close the incision, while not hindering the adequate wound healing progression. Currently, there is no surgical measuring device that could be used to determine the required closing forces, which can be very different depending on the patient. This paper presents a dynamometer to measure the tension forces to be applied while closing a surgical incision, and it simultaneously measures the distance between wound edges. It is a compass-like instrument. A mechanism between the two legs incorporates a load cell, whose signal is read by an electronic device that computes the values of the tension forces between wound edges. An angular position sensor at the pin joint between legs provides the distance between both sides of the incision. Measuring capabilities of the instrument prototype were verified at the laboratory. Thereafter, its functionality was demonstrated in experimental surgery tests. Therefore, the instrument could be very useful in clinical applications, assisting personalized surgical techniques.

  5. The Platformization of the Web: Making Web Data Platform Ready

    NARCIS (Netherlands)

    Helmond, A.

    2015-01-01

    In this article, I inquire into Facebook’s development as a platform by situating it within the transformation of social network sites into social media platforms. I explore this shift with a historical perspective on, what I refer to as, platformization, or the rise of the platform as the dominant

  6. Single-leg squats can predict leg alignment in dancers performing ballet movements in “turnout”

    Directory of Open Access Journals (Sweden)

    Hopper LS

    2016-11-01

    Full Text Available Luke S Hopper,1 Nahoko Sato,2 Andries L Weidemann1 1Western Australian Academy of Performing Arts, Edith Cowan University, Mt Lawley, WA, Australia; 2Department of Physical Therapy, Nagoya Gakuin University, Seto, Japan Abstract: The physical assessments used in dance injury surveillance programs are often adapted from the sports and exercise domain. Bespoke physical assessments may be required for dance, particularly when ballet movements involve “turning out” or external rotation of the legs beyond that typically used in sports. This study evaluated the ability of the traditional single-leg squat to predict the leg alignment of dancers performing ballet movements with turnout. Three-dimensional kinematic data of dancers performing the single-leg squat and five ballet movements were recorded and analyzed. Reduction of the three-dimensional data into a one-dimensional variable incorporating the ankle, knee, and hip joint center positions provided the strongest predictive model between the single-leg squat and the ballet movements. The single-leg squat can predict leg alignment in dancers performing ballet movements, even in “turned out” postures. Clinicians should pay careful attention to observational positioning and rating criteria when assessing dancers performing the single-leg squat. Keywords: injury, motion capture, clinical assessment

  7. Single-leg squats can predict leg alignment in dancers performing ballet movements in “turnout”

    Science.gov (United States)

    Hopper, Luke S; Sato, Nahoko; Weidemann, Andries L

    2016-01-01

    The physical assessments used in dance injury surveillance programs are often adapted from the sports and exercise domain. Bespoke physical assessments may be required for dance, particularly when ballet movements involve “turning out” or external rotation of the legs beyond that typically used in sports. This study evaluated the ability of the traditional single-leg squat to predict the leg alignment of dancers performing ballet movements with turnout. Three-dimensional kinematic data of dancers performing the single-leg squat and five ballet movements were recorded and analyzed. Reduction of the three-dimensional data into a one-dimensional variable incorporating the ankle, knee, and hip joint center positions provided the strongest predictive model between the single-leg squat and the ballet movements. The single-leg squat can predict leg alignment in dancers performing ballet movements, even in “turned out” postures. Clinicians should pay careful attention to observational positioning and rating criteria when assessing dancers performing the single-leg squat. PMID:27895518

  8. Effects of rhythmical muscle tension at 0.1Hz on cardiovascular resonance and the baroreflex.

    Science.gov (United States)

    Lehrer, Paul; Vaschillo, Evgeny; Trost, Zina; France, Christopher R

    2009-04-01

    This paper reports analysis of data from a previous study examining cardiovascular effects of rhythmical skeletal muscle tension (RSMT) at 0.1Hz. Our analysis examined whether 0.1Hz RSMT stimulates resonance properties of the cardiovascular system provided by baroreflex (BR) activity. Thirty-seven study participants tensed their large skeletal muscles, with and without crossing their legs, for 3-min periods at a rate of six tension/relaxation cycles/min. Tensing periods were preceded and followed by 3-min rest periods. RSMT elicited high-amplitude 0.1Hz oscillations in the cardiovascular system. We found increases in spectral power of ECG R-R interbeat interval (RRI), systolic blood pressure (SBP) and pulse transit time (PTT) at this frequency. The increases in SBP and PTT oscillations were greater than those in RRI. Only in SBP and PTT did total variability (standard deviation) increase. The phase angle between RRI and SBP oscillations was approximately 45 degrees . Although alpha low-frequency baroreflex gain was attenuated by RSMT, it was not significantly changed at 0.1Hz, consistent with BR-induced resonance effects. Our results are consistent with previous observations that 0.1Hz RSMT is effective in treating vasovagal reactions and indicate that the pathway is through resonance characteristics of the BR system. Implications for resonance applications for resonance in the sympathetically mediated vascular tone baroreflex closed loop are discussed.

  9. Toward a general psychological model of tension and suspense

    Directory of Open Access Journals (Sweden)

    Moritz eLehne

    2015-02-01

    Full Text Available Tension and suspense are powerful emotional experiences that occur in a wide variety of contexts (e.g., in music, film, literature, and everyday life. The omnipresence of tension experiences suggests that they build on very basic cognitive and affective mechanisms. However, the psychological underpinnings of tension experiences remain largely unexplained, and tension and suspense are rarely discussed from a general, domain-independent perspective. In this paper, we argue that tension experiences in different contexts (e.g., musical tension or suspense in a movie build on the same underlying psychological processes. We discuss key components of tension experiences and propose a domain-independent model of tension and suspense. According to this model, tension experiences originate from states of conflict, instability, dissonance, or uncertainty that trigger predictive processes directed at future events of emotional significance. We also discuss possible neural mechanisms underlying experiences of tension. The model provides a theoretical framework that can inform future empirical research on tension phenomena.

  10. Toward a general psychological model of tension and suspense

    Science.gov (United States)

    Lehne, Moritz; Koelsch, Stefan

    2015-01-01

    Tension and suspense are powerful emotional experiences that occur in a wide variety of contexts (e.g., in music, film, literature, and everyday life). The omnipresence of tension and suspense suggests that they build on very basic cognitive and affective mechanisms. However, the psychological underpinnings of tension experiences remain largely unexplained, and tension and suspense are rarely discussed from a general, domain-independent perspective. In this paper, we argue that tension experiences in different contexts (e.g., musical tension or suspense in a movie) build on the same underlying psychological processes. We discuss key components of tension experiences and propose a domain-independent model of tension and suspense. According to this model, tension experiences originate from states of conflict, instability, dissonance, or uncertainty that trigger predictive processes directed at future events of emotional significance. We also discuss possible neural mechanisms underlying tension and suspense. The model provides a theoretical framework that can inform future empirical research on tension phenomena. PMID:25717309

  11. Transactional Network Platform: Applications

    Energy Technology Data Exchange (ETDEWEB)

    Katipamula, Srinivas; Lutes, Robert G.; Ngo, Hung; Underhill, Ronald M.

    2013-10-31

    In FY13, Pacific Northwest National Laboratory (PNNL) with funding from the Department of Energy’s (DOE’s) Building Technologies Office (BTO) designed, prototyped and tested a transactional network platform to support energy, operational and financial transactions between any networked entities (equipment, organizations, buildings, grid, etc.). Initially, in FY13, the concept demonstrated transactions between packaged rooftop air conditioners and heat pump units (RTUs) and the electric grid using applications or "agents" that reside on the platform, on the equipment, on a local building controller or in the Cloud. The transactional network project is a multi-lab effort with Oakridge National Laboratory (ORNL) and Lawrence Berkeley National Laboratory (LBNL) also contributing to the effort. PNNL coordinated the project and also was responsible for the development of the transactional network (TN) platform and three different applications associated with RTUs. This document describes two applications or "agents" in details, and also summarizes the platform. The TN platform details are described in another companion document.

  12. Artificial Leg Design and Control Research of a Biped Robot with Heterogeneous Legs Based on PID Control Algorithm

    Directory of Open Access Journals (Sweden)

    Hualong Xie

    2015-04-01

    Full Text Available A biped robot with heterogeneous legs (BRHL is proposed to provide an ideal test-bed for intelligent bionic legs (IBL. To make artificial leg gait better suited to a human, a four-bar mechanism is used as its knee joint, and a pneumatic artificial muscle (PAM is used as its driving source. The static mathematical model of PAM is established and the mechanical model of a single degree of freedom of a knee joint driven by PAM is analyzed. A control simulation of an artificial leg based on PID control algorithm is carried out and the simulation results indicate that the artificial leg can simulate precisely a normal human walking gait.

  13. Surface tension measurement from the indentation of clamped thin films.

    Science.gov (United States)

    Xu, Xuejuan; Jagota, Anand; Paretkar, Dadhichi; Hui, Chung-Yuen

    2016-06-21

    We developed an indentation technique to measure the surface tension of relatively stiff solids. In the proposed method, a suspended thin solid film is indented by a rigid sphere and its deflection is measured by optical interferometry. The film deflection is jointly resisted by surface tension, elasticity and residual stress. Using a version of nonlinear von Karman plate theory that includes surface tension, we are able to separate the contribution of elasticity to the total tension in the film. Surface tension is determined by extrapolating the sum of surface tension and residual stress to zero film thickness. We measured the surface tension of polydimethylsiloxane (PDMS) using this technique and obtained a value of 19.5 ± 3.6 mN m(-1), consistent with the surface energy of PDMS reported in the literature.

  14. Menstrual tension-type headache: evidence for its existence.

    Science.gov (United States)

    Arjona, Antonio; Rubi-Callejon, Jose; Guardado-Santervas, Pedro; Serrano-Castro, Pedro; Olivares, Jesus

    2007-01-01

    To determine whether menstrual tension-type headache is a real disorder. An appendix was included in the second edition of the International Classification of Headache Disorders by the International Headache Society. Diagnostic criteria are proposed in this appendix for 2 types of menstrual migraine: pure menstrual migraine without aura and menstrually related migraine without aura. References to menstrual tension-type headache do not appear in this classification. In a neurological outpatient clinic 165 patients were identified in whom headache was related to menstruation and the criteria of the International Classification of Headache Disorders for menstrual migraine adapted to menstrual tension-type headache were applied. Twenty-one patients met the criteria of menstrual tension-type headache, 6 for pure menstrual tension-type headache, and 15 for menstrually related tension-type headache. Menstrual tension-type headache is a real condition that should be recognized in the International Classification of Headache Disorders.

  15. Don't break a leg: running birds from quail to ostrich prioritise leg safety and economy on uneven terrain.

    Science.gov (United States)

    Birn-Jeffery, Aleksandra V; Hubicki, Christian M; Blum, Yvonne; Renjewski, Daniel; Hurst, Jonathan W; Daley, Monica A

    2014-11-01

    Cursorial ground birds are paragons of bipedal running that span a 500-fold mass range from quail to ostrich. Here we investigate the task-level control priorities of cursorial birds by analysing how they negotiate single-step obstacles that create a conflict between body stability (attenuating deviations in body motion) and consistent leg force-length dynamics (for economy and leg safety). We also test the hypothesis that control priorities shift between body stability and leg safety with increasing body size, reflecting use of active control to overcome size-related challenges. Weight-support demands lead to a shift towards straighter legs and stiffer steady gait with increasing body size, but it remains unknown whether non-steady locomotor priorities diverge with size. We found that all measured species used a consistent obstacle negotiation strategy, involving unsteady body dynamics to minimise fluctuations in leg posture and loading across multiple steps, not directly prioritising body stability. Peak leg forces remained remarkably consistent across obstacle terrain, within 0.35 body weights of level running for obstacle heights from 0.1 to 0.5 times leg length. All species used similar stance leg actuation patterns, involving asymmetric force-length trajectories and posture-dependent actuation to add or remove energy depending on landing conditions. We present a simple stance leg model that explains key features of avian bipedal locomotion, and suggests economy as a key priority on both level and uneven terrain. We suggest that running ground birds target the closely coupled priorities of economy and leg safety as the direct imperatives of control, with adequate stability achieved through appropriately tuned intrinsic dynamics. © 2014. Published by The Company of Biologists Ltd.

  16. Restless legs syndrome in patients on dialysis

    Directory of Open Access Journals (Sweden)

    Al-Jahdali Hamdan

    2009-01-01

    Full Text Available Restless legs syndrome (RLS is an extremely distressing problem experienced by patients on dialysis; the prevalence appears to be greater than in the general population, with a wide variation from 6.6% to 80%. The diagnosis of RLS is a clinical one, and its definition has been clarified and standardized by internationally recognized diagnostic criteria, published in 1995 by the International Restless Legs Syndrome Study Group (IRLSSG. This study was designed to find out the prevalence of RLS in Saudi patients with end-stage renal disease (ESRD on maintenance dialysis. This is a cross sectional study carried out between May and Sept 2007 at two centers, King Abdulaziz Medical City-King Fahad National Guard Hospital (KAMC-KFNGH, Riyadh and King Faisal Specialist Hospital and Research Centre (KFHRC, Jeddah, Saudi Arabia. Data were gathered on 227 Saudi patients on chronic maintenance hemodialysis or chronic peritoneal dialysis. The prevalence of RLS was measured using IRLSSG′s RLS Questionnaire (RLSQ. Potential risk factors for RLS including other sleep disorders, underlying cause of chronic renal failure, duration on dialysis, dialysis shift, biochemical tests and demographic data were also evaluated. The overall prevalence of RLS was 50.22% including 53.7% males and 46.3% females. Their mean age was 55.7 ± 17.2 years and mean duration on dialysis 40.4 ± 37.8 months. Significant predictors of RLS were history of diabetes mellitus (DM, coffee intake, afternoon dialysis, gender and type of dialysis (P= 0.03, 0.01, < 0.001, 0.05 and 0.009 respectively. Patients with RLS were found to be at increased risk of having insomnia and excessive daytime sleepiness (EDS (P= < 0.001 and 0.001, respectively. Our study suggests that RLS is a very common problem in dialysis population and was significantly associated with other sleep disorders, particularly insomnia, and EDS. Optimal care of dialysis patient should include particular attention to the diagnosis

  17. [Design and application of medical electric leg-raising machine].

    Science.gov (United States)

    Liang, Jintang; Chen, Jinyuan; Zhao, Zixian; Lin, Jinfeng; Li, Juanhong; Zhong, Jingliang

    2017-08-01

    Passive leg raising is widely used in clinic, but it lacks of specialized mechanical raise equipment. It requires medical staff to raise leg by hand or requires a multi-functional bed to raise leg, which takes time and effort. Therefore we have developed a new medical electric leg-raising machine. The equipment has the following characteristics: simple structure, stable performance, easy operation, fast and effective, safe and comfortable. The height range of the lifter is 50-120 cm, the range of the angle of raising leg is 10degree angle-80degree angle, the maximum supporting weight is 40 kg. Because of raising the height of the lower limbs and making precise angle, this equipment can completely replace the traditional manner of lifting leg by hand with multi-functional bed to lift patients' leg and can reduce the physical exhaustion and time consumption of medical staff. It can change the settings at any time to meet the needs of the patient; can be applied to the testing of PLR and dynamically assessing the hemodynamics; can prevent deep vein thrombosis and some related complications of staying in bed; and the machine is easy to be cleaned and disinfected, which can effectively avoid hospital acquired infection and cross infection; and can also be applied to emergency rescue of various disasters and emergencies.

  18. Evaluation of Thermoelectric Performance and Durability of Functionalized Skutterudite Legs

    Science.gov (United States)

    Skomedal, Gunstein; Kristiansen, Nils R.; Sottong, Reinhard; Middleton, Hugh

    2017-04-01

    Thermoelectric generators are a promising technology for waste heat recovery. As new materials and devices enter a market penetration stage, it is of interest to employ fast and efficient measurement methods to evaluate the long-term stability of thermoelectric materials in combination with metallization and coating (functionalized thermoelectric legs). We have investigated a method for measuring several thermoelectric legs simultaneously. The legs are put under a common temperature gradient, and the electrical characteristics of each leg are measured individually during thermal cycling. Using this method, one can test different types of metallization and coating applied to skutterudite thermoelectric legs and look at the relative changes over time. Postcharacterization of these initial tests with skutterudite legs using a potential Seebeck microprobe and an electron microscope showed that oxidation and interlayer diffusion are the main reasons for the gradual increase in internal resistance and the decrease in open-circuit voltage. Although we only tested skutterudite material in this work, the method is fully capable of testing all kinds of material, metallization, and coating. It is thus a promising method for studying the relationship between failure modes and mechanisms of functionalized thermoelectric legs.

  19. Nurses' knowledge about venous leg ulcer care: a literature review.

    Science.gov (United States)

    Ylönen, M; Stolt, M; Leino-Kilpi, H; Suhonen, R

    2014-06-01

    There is an increasing prevalence of venous leg ulcers coinciding with increasing older people populations. They are therefore important health problems, which restrict daily activities and incur high costs. Efficient and comprehensive nursing care for people with venous leg ulcers requires knowledge of causes, presentations and characteristics, the effects that venous leg ulcers have on individuals and nursing care with evidence-based treatment. To identify the gaps between nurses' demonstrated knowledge of venous leg ulcers and the related nursing care treatment with evidence-based nursing care. A computerized search using MEDLINE, CINAHL the COCHRANE LIBRARY was conducted. The initial search yielded 174 citations from which 16 relevant articles were included in this review. Four themes in venous leg ulcer nursing care emerged demonstrating nurses' knowledge gaps: assessment, physiology and the healing process, nursing care and dressings, and compression treatment. This review suggests that there is a lack of knowledge related to venous leg ulcer physiology, the healing process and how this influences care and treatment. Nurses may not be using the evidence base sufficiently well to support ulcer healing and patient well-being. There is a need for a positive work culture development and ongoing educational programmes aimed at improving nurses' knowledge of venous leg ulcer treatment and care, which address the themes within the results of this review. © 2014 International Council of Nurses.

  20. The need for a National Service Framework for leg ulcers.

    Science.gov (United States)

    Bulbulia, R A; Poskitt, K R

    2010-10-01

    Leg ulcers are common and costly to treat, and the quality of care provided to patients with this condition varies widely across the UK. The introduction of specialized community-based leg ulcer clinics in Gloucestershire has been associated with increased ulcer healing rates and decreased rates of ulcer recurrence, but this model of care has not been widely replicated. One way of ending this 'postcode lottery' is to produce a National Service Framework for leg ulcers, with the aim of delivering high-quality evidence-based care via such clinics under the supervision of local consultant vascular surgeons. Existing National Service Frameworks cover a range of common conditions that are, like leg ulceration, associated with significant morbidity, disability and resource use. These documents aim to raise quality and decrease regional variations in health care across the National Health Service, and leg ulceration fulfils all the necessary criteria for inclusion in a National Service Framework. Centrally defined standards of care for patients with leg ulceration, and the reorganization and restructuring of local services to allow the accurate assessment and treatment of such patients are required. Without a National Service Framework to drive up the quality of care across the country, the treatment of patients with leg ulcers will remain suboptimal for the majority of those who suffer from this common and debilitating condition.

  1. Windows Azure Platform

    CERN Document Server

    Redkar, Tejaswi

    2010-01-01

    The Azure Services Platform is a brand-new cloud-computing technology from Microsoft. It is composed of four core components-Windows Azure, .NET Services, SQL Services, and Live Services-each with a unique role in the functioning of your cloud service. It is the goal of this book to show you how to use these components, both separately and together, to build flawless cloud services. At its heart Windows Azure Platform is a down-to-earth, code-centric book. This book aims to show you precisely how the components are employed and to demonstrate the techniques and best practices you need to know

  2. Planetary Web Resource Platform

    Science.gov (United States)

    Xing, Z.

    2016-12-01

    In this presentation, we would like to discuss our recent work ona web-based data platform, that can simplify the use of planetarymission products and unify the operation of key applications.This platform is extensible and flexible. Products and applicationscan be added to or removed from it in a distributed fashion.It is built on top of known and proven information technologiesfor data exposure and discovery. Live examples of the end-to-endweb services and in-browser clients for current planetary missionswill be demonstrated.

  3. Wireless sensor platform

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Pooran C.; Killough, Stephen M.; Kuruganti, Phani Teja

    2017-08-08

    A wireless sensor platform and methods of manufacture are provided. The platform involves providing a plurality of wireless sensors, where each of the sensors is fabricated on flexible substrates using printing techniques and low temperature curing. Each of the sensors can include planar sensor elements and planar antennas defined using the printing and curing. Further, each of the sensors can include a communications system configured to encode the data from the sensors into a spread spectrum code sequence that is transmitted to a central computer(s) for use in monitoring an area associated with the sensors.

  4. Windows Azure Platform

    CERN Document Server

    Redkar, Tejaswi

    2011-01-01

    The Windows Azure Platform has rapidly established itself as one of the most sophisticated cloud computing platforms available. With Microsoft working to continually update their product and keep it at the cutting edge, the future looks bright - if you have the skills to harness it. In particular, new features such as remote desktop access, dynamic content caching and secure content delivery using SSL make the latest version of Azure a more powerful solution than ever before. It's widely agreed that cloud computing has produced a paradigm shift in traditional architectural concepts by providin

  5. Rarefaction Shock Wave Cutter for Offshore Oil-Gas Platform Removal Final Report CRADA No. TC02009.0

    Energy Technology Data Exchange (ETDEWEB)

    Glenn, L. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Barker, J. [Halliburton Energy Services, Alvarado, TX (United States)

    2017-09-06

    This was a collaborative effort between Lawrence Livermore National Security, LLC/Lawrence Livermore National Laboratory (LLNL) (formerly the University of California) and Jet Research Center, a wholly owned division of Halliburton Energy Services, Inc. to design and prototype an improved explosive cutter for cutting the support legs of offshore oil and gas platforms.

  6. Therapeutic ultrasound for venous leg ulcers.

    Science.gov (United States)

    Cullum, Nicky; Liu, Zhenmi

    2017-05-15

    Venous leg ulcers are a type of chronic, recurring, complex wound that is more common in people aged over 65 years. Venous ulcers pose a significant burden to patients and healthcare systems. While compression therapy (such as bandages or stockings) is an effective first-line treatment, ultrasound may have a role to play in healing venous ulcers. To determine whether venous leg ulcers treated with ultrasound heal more quickly than those not treated with ultrasound. We searched the Cochrane Wounds Specialised Register (searched 19 September 2016); the Cochrane Central Register of Controlled Trials (CENTRAL; the Cochrane Library 2016, Issue 8); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations, MEDLINE Daily and Epub Ahead of Print) (1946 to 19 September 2016); Ovid Embase (1974 to 19 September 2016); and EBSCO CINAHL Plus (1937 to 19 September 2016). We also searched three clinical trials registries and the references of included studies and relevant systematic reviews. There were no restrictions based on language, date of publication or study setting. Randomised controlled trials (RCTs) that compared ultrasound with no ultrasound. Eligible non-ultrasound comparator treatments included usual care, sham ultrasound and alternative leg ulcer treatments. Two authors independently assessed the search results and selected eligible studies. Details from included studies were summarised using a data extraction sheet, and double-checked. We attempted to contact trial authors for missing data. Eleven trials are included in this update; 10 of these we judged to be at an unclear or high risk of bias. The trials were clinically heterogeneous with differences in duration of follow-up, and ultrasound regimens. Nine trials evaluated high frequency ultrasound; seven studies provided data for ulcers healed and two provided data on change in ulcer size only. Two trials evaluated low frequency ultrasound and both reported ulcers healed data.It is uncertain whether high

  7. RAW CHICKEN LEG AND BREAST SENSORY EVALUATION

    Directory of Open Access Journals (Sweden)

    Octavian Baston

    2010-01-01

    Full Text Available In the paper we presented a method of sensorial evaluation for chicken meat (red and white. This is a descriptive method of analysis. It was perform with trained assessors for chicken refrigerated raw meat organoleptical evaluation. The sensorial attributes considered were: external aspect of anatomical part of chicken analyzed by slime, the surface odor, the skin and muscle color and muscular elasticity. Color was determined for the skin and white and red muscles. Our scale of analysis is formed by three values that characterize each quality attribute. The trained assessor appreciated the sensorial quality of raw anatomical part of chicken as excellent, acceptable and unacceptable. The objectives were: to establish the sensorial attributes to be analyzed for each type of muscular fiber, to describe the quality of each considered attribute and to realize a sensorial scale of quantification for the considered sensorial attributes. Our purpose was to determine the quality of the red and white refrigerated raw chicken anatomical parts (respectively for legs and breasts after one week of storage.

  8. Primary headaches in restless legs syndrome patients

    Directory of Open Access Journals (Sweden)

    Ravi Gupta

    2012-01-01

    Full Text Available Earlier studies conducted among migraineurs have shown an association between migraine and restless legs syndrome (RLS. We chose RLS patients and looked for migraine to exclude sample bias. Materials and Methods: 99 consecutive subjects of idiopathic RLS were recruited from the sleep clinic during four months period. Physician diagnosis of headache and depressive disorder was made with the help of ICHD-2 and DSM-IV-TR criteria, respectively. Sleep history was gathered. Severity of RLS and insomnia was measured using IRLS (Hindi version and insomnia severity index Hindi version, respectively. Chi-square test, one way ANOVA and t-test were applied to find out the significance. Results: Primary headache was seen in 51.5% cases of RLS. Migraine was reported by 44.4% subjects and other types of ′primary headaches′ were reported by 7.1% subjects. Subjects were divided into- RLS; RLS with migraine and RLS with other headache. Females outnumbered in migraine subgroup (χ2 =16.46, P<0.001. Prevalence of depression (χ2 =3.12, P=0.21 and family history of RLS (χ2 =2.65, P=0.26 were not different among groups. Severity of RLS (P=0.22 or insomnia (P=0.43 were also similar. Conclusion: Migraine is frequently found in RLS patients in clinic based samples. Females with RLS are prone to develop migraine. Depression and severity of RLS or insomnia do not affect development of headache.

  9. Clinical correlates of the restless legs syndrome

    Directory of Open Access Journals (Sweden)

    Luis Fabiano Marin

    2012-07-01

    Full Text Available OBJECTIVE: To determine the clinical correlates of the restless legs syndrome (RLS in a Brazilian sleep disorders center. METHODS: We retrospectively studied 118 patients with RLS from January, 2004, to December, 2010. The analyzed variables were: age at disease onset, gender, race, years of school instruction, primary and secondary RLS, and treatment options. RESULTS: Among the studied patients, 83.9% were women with a female/male sex ratio of 5:1. Mean age of the patients at symptom onset ± standard deviation was 41.7±17.9 years-old. The primary RLS was found in 85% of patients. The other 15% remainders consisted of secondary forms, and they were associated with neuropathy, iron deficiency anemia, end-stage renal disease, or Parkinson's disease. Drug therapy for RLS was introduced in 67% of patients. CONCLUSIONS: Most patients presented primary RLS with an early disease onset. Further epidemiological studies are welcomed to provide better information on secondary RLS in Brazil.

  10. [Prophylaxis of Recurrent Venous Leg Ulcer].

    Science.gov (United States)

    Kroeger, K; Storck, M; Kujath, P; Rabe, E; Dissemond, J

    2017-06-01

    Venous leg ulcer (VLU) counts among the most common chronic wounds in Europe. Treatment is lengthy, cumbersome and costly, and there is a high rate of recurrence. This review shows the measures that should be offered to every patient with healed VLU to permanently prevent recurrence. To prevent VLU in case of varicose veins, the progression of chronic venous insufficiency (CVI) has to be stopped. There is convincing evidence that the effective treatment of varicose veins reduces the recurrence rate in patients with VLU. In patients with post-thrombotic syndrome (PTS), further thrombosis should be prevented through targeted prophylaxis of new thromboembolic events. The benefit of endovascular revascularization on the VLU recurrence rate in patients with post-thrombotic damage in the pelvic veins has not been proven in clinical studies. On the other hand, it has been clearly demonstrated in several studies that compression therapy is the basic procedure for the prevention of recurrent VLU in patients with varicose veins or PTS, regardless of whether other measures have been implemented or not. Good adherence in patients with compression therapy is more important than choosing the highest possible compression class. Future efforts for patients with VLU must aim to provide therapists with tools and treatment strategies to guide their patients and to increase patients' acceptance and understanding of the importance of self-management, in particular regarding compression therapy for the prevention of recurrent VLU. Georg Thieme Verlag KG Stuttgart · New York.

  11. Pramipexole alters thermoregulation in restless legs syndrome.

    Science.gov (United States)

    Salminen, Aaro V; Rimpilä, Ville; Polo, Olli

    2014-12-15

    Previous studies have associated restless legs syndrome (RLS) with peripheral hypoxia and impaired thermoregulation in the lower extremities. We performed long-term monitoring of skin temperatures in order to investigate whether these findings could be explained by reduced blood flow to the peripheral tissues. 96-hour continuous measurements of skin temperature were performed both in the distal and proximal parts of the body of 15 patients with RLS and 14 healthy controls. During the recording, the patients participated in suggested immobilization tests both with and without pramipexole medication. We found no baseline differences in distal or proximal skin temperature between patients and controls in daytime or during immobilization. However, pramipexole significantly increased distal skin temperature in the patient group during immobilization (31.1°C vs. 32.9°C, p thermoregulation and the previous studies might have been biased by medication. Dopaminergic medication is a major confounding factor when assessing peripheral phenomena in RLS and should be controlled for in the future studies. © 2014 American Academy of Sleep Medicine.

  12. Restless legs syndrome and pregnancy: A review

    Science.gov (United States)

    Srivanitchapoom, Prachaya; Pandey, Sanjay; Hallett, Mark

    2014-01-01

    Restless legs syndrome (RLS) is a common sensorimotor neurological disorder that is diagnosed according to the revised criteria of the International RLS Study Group (IRLSSG). The pathophysiology of RLS is still unknown and its prevalence is influenced by ethnicity, age, and gender. RLS is divided into two types by etiology: primary or idiopathic and secondary. Primary RLS is strongly influenced by a genetic component while secondary RLS is caused by other associated conditions such as end-stage renal disease or peripheral neuropathy. Another common condition associated with RLS is pregnancy. The prevalence of RLS during pregnancy is two to three times higher than in the normal population and is influenced by the trimester and the number of parity. The main mechanisms that may contribute to the pathophysiology of RLS during pregnancy are hormonal changes and iron and folate status. Standard medications for treating RLS during pregnancy are not established. Most medications have been used according to the evidence from non-pregnant patients. Therefore, consideration of the medical treatment for treating RLS during pregnancy should be balanced between the benefit of relieving the symptoms and maternal and fetal risk. In general, the prognosis of RLS during pregnancy is good and symptoms are usually relieved after delivery. PMID:24768121

  13. Adjuvant Biological Therapies in Chronic Leg Ulcers

    Directory of Open Access Journals (Sweden)

    Natalia Burgos-Alonso

    2017-11-01

    Full Text Available Current biological treatments for non-healing wounds aim to address the common deviations in healing mechanisms, mainly inflammation, inadequate angiogenesis and reduced synthesis of extracellular matrix. In this context, regenerative medicine strategies, i.e., platelet rich plasmas and mesenchymal stromal cell products, may form part of adjuvant interventions in an integral patient management. We synthesized the clinical experience on ulcer management using these two categories of biological adjuvants. The results of ten controlled trials that are included in this systematic review favor the use of mesenchymal stromal cell based-adjuvants for impaired wound healing, but the number and quality of studies is moderate-low and are complicated by the diversity of biological products. Regarding platelet-derived products, 18 controlled studies investigated their efficacy in chronic wounds in the lower limb, but the heterogeneity of products and protocols hinders clinically meaningful quantitative synthesis. Most patients were diabetic, emphasizing an unmet medical need in this condition. Overall, there is not sufficient evidence to inform routine care, and further clinical research is necessary to realize the full potential of adjuvant regenerative medicine strategies in the management of chronic leg ulcers.

  14. Superficial tension: experimental model with simple materials

    Directory of Open Access Journals (Sweden)

    Tintori Ferreira, María Alejandra

    2012-09-01

    Full Text Available In this work appears a didactic offer based on an experimental activity using materials of very low cost, orientated to achieving that the student understand and interpret the phenomenon of superficial tension together with the importance of the modeling in sciences. It has as principal aim of education bring the student over to the mechanics of the static fluids and the intermolecular forces, combining scientific contents with questions near to the student what provides an additional motivation to the reflection of the scientific investigation.

  15. Surface Tension Driven Convection Experiment Completed

    Science.gov (United States)

    Jacobson, Thomas P.; Sedlak, Deborah A.

    1997-01-01

    The Surface Tension Driven Convection Experiment (STDCE) was designed to study basic fluid mechanics and heat transfer on thermocapillary flows generated by temperature variations along the free surfaces of liquids in microgravity. STDCE first flew on the USML-1 mission in July 1992 and was rebuilt for the USML-2 mission that was launched in October 1995. This was a collaborative project with principal investigators from Case Western Reserve University (CWRU), Professors Simon Ostrach and Yasuhiro Kamotani, along with a team from the NASA Lewis Research Center composed of civil servants and contractors from Aerospace Design & Fabrication, Inc. (ADF), Analex, and NYMA, Inc.

  16. Small-Bolt Torque-Tension Tester

    Science.gov (United States)

    Posey, Alan J.

    2009-01-01

    The device described here measures the torque-tension relationship for fasteners as small as #0. The small-bolt tester consists of a plate of high-strength steel into which three miniature load cells are recessed. The depth of the recess is sized so that the three load cells can be shimmed, the optimum height depending upon the test hardware. The three miniature load cells are arranged in an equilateral triangular configuration with the test bolt aligned with the centroid of the three. This is a kinematic arrangement.

  17. Legs and Claws Condition and Lameness in Sows

    OpenAIRE

    Renata Relic; Dragan Rogozarski; Radomir Savic; Mila Savic; Jovan Bojkovski; Zsolt Becskei

    2016-01-01

    Lameness is a multi-factorial condition that depends on managerial as well as genetic variables, but often is related to legs and feet condition of the animals. The aim of the study was to give an overview of legs and claws condition and the presence of lameness in sows at one industrial farm. Total 130 animals (90 dry i.e. pregnant and 40 lactating sows) were observed. The occurrence of leg joints swellings, than claws condition (toes length, dew claw condition, cracked wall) and lameness (i...

  18. Interpreting expressive performance through listener judgments of musical tension

    Science.gov (United States)

    Farbood, Morwaread M.; Upham, Finn

    2013-01-01

    This study examines listener judgments of musical tension for a recording of a Schubert song and its harmonic reduction. Continuous tension ratings collected in an experiment and quantitative descriptions of the piece's musical features, include dynamics, pitch height, harmony, onset frequency, and tempo, were analyzed from two different angles. In the first part of the analysis, the different processing timescales for disparate features contributing to tension were explored through the optimization of a predictive tension model. The results revealed the optimal time windows for harmony were considerably longer (~22 s) than for any other feature (~1–4 s). In the second part of the analysis, tension ratings for the individual verses of the song and its harmonic reduction were examined and compared. The results showed that although the average tension ratings between verses were very similar, differences in how and when participants reported tension changes highlighted performance decisions made in the interpretation of the score, ambiguity in tension implications of the music, and the potential importance of contrast between verses and phrases. Analysis of the tension ratings for the harmonic reduction also provided a new perspective for better understanding how complex musical features inform listener tension judgments. PMID:24416024

  19. Clinical interventions for venous leg ulcers: Proposals to improve the quality of clinical leg ulcer research.

    Science.gov (United States)

    Lazarus, Gerald S; Kirsner, Robert S; Zenilman, Jonathan; Valle, M Frances; Margolis, David J; Cullum, Nicky; Driver, Vickie R; Gould, Lisa; Lindsay, Ellie; Tunis, Sean; Marston, William; Bass, Eric; Ennis, William; Davidson, Jeffrey; Bowden, Jeremy

    2016-09-01

    The present status of clinical leg ulcer healing research was reviewed by 25 experts over 2 days on September 28 and 29, 2015. Multiple clinical effectiveness reviews were presented suggesting that published clinical wound healing research often does not meet present (2015) evidence based standards. Specific areas requiring remediation were highlighted and approaches to overcoming existing challenges were proposed. Participants using anonymous voting technology developed an action plan to resolve perceived deficiencies. Statements were accepted if 75% of participants agreed. Older patients with a high frequency of comorbid conditions posed particular difficulties in designing clinical research protocols and better diagnostic categorization is necessary A standardized model template for collecting information about diagnosis and evaluation of the effect of interventions on healing of all types of leg ulcers was considered a high priority. Such a model template could be modified depending on the specific etiology of the leg ulcers. Generally agreed on quantifiable standards to establish degree of morbidity was considered a high priority. There was universal agreement that sources of funding and conflicts of interest needed to be disclosed in presentations and all publications. All clinical research studies should be registered with appropriate authorities. There was substantial enthusiasm for a clinical research network with quality standards for membership and an advisory research core available to investigators. Such a network should be funded and actively managed to insure long-term viability. The governance of such an entity needs to be established by the wound care community. The present trend to integrate patients into the clinical research process was endorsed and there was enthusiasm to develop patient advocacy for wound healing research. © 2016 by the Wound Healing Society.

  20. Platform Performance and Challenges - using Platforms in Lego Company

    DEFF Research Database (Denmark)

    Munk, Lone; Mortensen, Niels Henrik

    2009-01-01

    This article studies the performance and challenges of using nine implemented product platforms in LEGO Company. Most of these do produce results, but do not meet their goals due to challenges in their usage in the daily product. The main challenges are that the platforms are not being used...... by the product defining users (product developers) and platform erosion. When the platforms are not used it is due to: unsuitable calculation models, lack of goals, rewards or benefits from management, unattractive tradeoffs and difficulties in understanding the platform. This indicates that platform design...

  1. Numerical simulation of active track tensioning system for autonomous hybrid vehicle

    Science.gov (United States)

    Mȩżyk, Arkadiusz; Czapla, Tomasz; Klein, Wojciech; Mura, Gabriel

    2017-05-01

    One of the most important components of a high speed tracked vehicle is an efficient suspension system. The vehicle should be able to operate both in rough terrain for performance of engineering tasks as well as on the road with high speed. This is especially important for an autonomous platform that operates either with or without human supervision, so that the vibration level can rise compared to a manned vehicle. In this case critical electronic and electric parts must be protected to ensure the reliability of the vehicle. The paper presents a dynamic parameters determination methodology of suspension system for an autonomous high speed tracked platform with total weight of about 5 tonnes and hybrid propulsion system. Common among tracked vehicles suspension solutions and cost-efficient, the torsion-bar system was chosen. One of the most important issues was determining optimal track tensioning - in this case an active hydraulic system was applied. The selection of system parameters was performed with using numerical model based on multi-body dynamic approach. The results of numerical analysis were used to define parameters of active tensioning control system setup. LMS Virtual.Lab Motion was used for multi-body dynamics numerical calculation and Matlab/SIMULINK for control system simulation.

  2. Gender and bilateral differences in single-leg countermovement jump performance with comparison to a double-leg jump.

    Science.gov (United States)

    Stephens, Thomas M; Lawson, Brooke R; DeVoe, Dale E; Reiser, Raoul F

    2007-08-01

    Expectations may be for both legs to function identically during single- and double-leg vertical jumps. However, several reasons might prevent this from occurring. The goals of this investigation were twofold: assess the presence of side-to-side jump height differences during single-leg jumps in a homogenous group of healthy subjects and determine if those with a jump height asymmetry possessed consistent biomechanical differences during single-and double-leg jumps. Thirteen men and 12 women with competitive volleyball experience volunteered for the study. Significance was assessed at p greater maximum ground reaction forces and ankle joint powers on their DL whereas the women had no differences during the single-leg jumps. The only side-to-side differences that existed during the double-leg jumps were in the average ground reaction forces during propulsion. These findings suggest that equality of single-leg jump performance is the exception rather than the norm, with identification of consistent biomechanical attributes difficult within a group.

  3. Creative Platform Learning (CPL)

    DEFF Research Database (Denmark)

    Christensen, Jonna Langeland; Hansen, Søren

    Creative Platform Learning (CPL) er en pædagogisk metode, der skaber foretagsomme og innovative elever, der kan anvende deres kreativitet til at lære nyt. Ifølge den nye skolereform skal Innovation og entreprenørskab tydeliggøres i alle fag. I CPL er det en integreret del af undervisningen...

  4. Games and Platform Decisions

    DEFF Research Database (Denmark)

    Hansen, Poul H. Kyvsgård; Mikkola, Juliana Hsuan

    2007-01-01

    is the application of on-line games in order to provide training for decision makers and in order to generate overview over the implications of platform decisions. However, games have to be placed in a context with other methods and we argue that a mixture of games, workshops, and simulations can provide improved...

  5. Education Platforms for America

    Science.gov (United States)

    District Administration, 2012

    2012-01-01

    What is at stake for K12 education in next month's presidential election? Both President Barack Obama (Democratic Party) and Gov. Mitt Romney (Republican Party) say improving education will be a top priority in their administrations, but their policies and initiatives would likely be quite different. While political platforms rarely offer detailed…

  6. Postgraduate programmes as platform

    NARCIS (Netherlands)

    drs Ben Smit; Prof.Dr. Petra Ponte; dr Jacqueline van Swet

    2007-01-01

    Typical of postgraduate courses for experienced teachers is the wealth of professional experience that the studetns bring with them. Such students can examine their own practice, for which they are fully responsible. Authors from diverse backgrounds address important aspects of the platform, such as

  7. CERN Neutrino Platform Hardware

    CERN Document Server

    Nelson, Kevin

    2017-01-01

    My summer research was broadly in CERN's neutrino platform hardware efforts. This project had two main components: detector assembly and data analysis work for ICARUS. Specifically, I worked on assembly for the ProtoDUNE project and monitored the safety of ICARUS as it was transported to Fermilab by analyzing the accelerometer data from its move.

  8. The Creative Platform

    DEFF Research Database (Denmark)

    Byrge, Christian; Hansen, Søren

    whether you consider thirdgrade teaching, human-resource development, or radical new thinking in product development in a company. The Creative Platform was developed at Aalborg University through a series of research-and-development activities in collaboration with educational institutions and private...

  9. Ground reaction force and 3D biomechanical characteristics of walking in short-leg walkers.

    Science.gov (United States)

    Zhang, Songning; Clowers, Kurt G; Powell, Douglas

    2006-12-01

    Short-leg walking boots offer several advantages over traditional casts. However, their effects on ground reaction forces (GRF) and three-dimensional (3D) biomechanics are not fully understood. The purpose of the study was to examine 3D lower extremity kinematics and joint dynamics during walking in two different short-leg walking boots. Eleven (five females and six males) healthy subjects performed five level walking trials in each of three conditions: two testing boot conditions, Gait Walker (DeRoyal Industries, Inc.) and Equalizer (Royce Medical Co.), and one pair of laboratory shoes (Noveto, Adidas). A force platform and a 6-camera Vicon motion analysis system were used to collect GRFs and 3D kinematic data during the testing session. A one-way repeated measures analysis of variance (ANOVA) was used to evaluate selected kinematic, GRF, and joint kinetic variables (p<0.05). The results revealed that both short-leg walking boots were effective in minimizing ankle eversion and hip adduction. Neither walker increased the bimodal vertical GRF peaks typically observed in normal walking. However, they did impose a small initial peak (<1BW) earlier in the stance phase. The Gait Walker also exhibited a slightly increased vertical GRF during midstance. These characteristics may be related to the sole materials/design, the restriction of ankle movements, and/or the elevated heel heights of the tested walkers. Both walkers appeared to increase the demand on the knee extensors while they decreased the demand of the knee and hip abductors based on the joint kinetic results.

  10. Kinematics and dynamics analysis of a quadruped walking robot with parallel leg mechanism

    Science.gov (United States)

    Wang, Hongbo; Sang, Lingfeng; Hu, Xing; Zhang, Dianfan; Yu, Hongnian

    2013-09-01

    It is desired to require a walking robot for the elderly and the disabled to have large capacity, high stiffness, stability, etc. However, the existing walking robots cannot achieve these requirements because of the weight-payload ratio and simple function. Therefore, Improvement of enhancing capacity and functions of the walking robot is an important research issue. According to walking requirements and combining modularization and reconfigurable ideas, a quadruped/biped reconfigurable walking robot with parallel leg mechanism is proposed. The proposed robot can be used for both a biped and a quadruped walking robot. The kinematics and performance analysis of a 3-UPU parallel mechanism which is the basic leg mechanism of a quadruped walking robot are conducted and the structural parameters are optimized. The results show that performance of the walking robot is optimal when the circumradius R, r of the upper and lower platform of leg mechanism are 161.7 mm, 57.7 mm, respectively. Based on the optimal results, the kinematics and dynamics of the quadruped walking robot in the static walking mode are derived with the application of parallel mechanism and influence coefficient theory, and the optimal coordination distribution of the dynamic load for the quadruped walking robot with over-determinate inputs is analyzed, which solves dynamic load coupling caused by the branches’ constraint of the robot in the walk process. Besides laying a theoretical foundation for development of the prototype, the kinematics and dynamics studies on the quadruped walking robot also boost the theoretical research of the quadruped walking and the practical applications of parallel mechanism.

  11. Strategies for equilibrium maintenance during single leg standing on a wobble board.

    Science.gov (United States)

    Silva, Priscila de Brito; Oliveira, Anderson Souza; Mrachacz-Kersting, Natalie; Laessoe, Uffe; Kersting, Uwe Gustav

    2016-02-01

    The aim of this study was to identify and compare movement strategies used to maintain balance while single leg standing on either a firm surface (FS) or on a wobble board (WB). In 17 healthy men, retroreflective markers were positioned on the xiphoid process and nondominant lateral malleolus to calculate trunk and contralateral-leg excursion (EXC) and velocity (VEL), and center of pressure (CoP) EXC and VEL during FS on a force platform. From the WB test, standing time (WBTIME) was determined and the board's angular EXC and VEL were calculated from four markers on the WB as surrogate measures for CoP dynamics. Electromyographic average rectified values (ARV) from eight leg and thigh muscles of the supporting limb were calculated for both tasks. WB ARV amplitudes were normalized with respect to the value of FS ARV and presented significantly higher peroneus longus and biceps femoris activity (p<0.05). WB standing time was correlated to trunk sagittal plane velocity (r=-0.73 at p=0.016) and excursion (r=-0.67 at p=0.03). CoP and WB angular movement measures were weakly and not significantly correlated between tasks. This lack of correlation indicates that WB balance maintenance requires movement beyond the ankle strategy as described for the FS task. WB standing likely demands different biomechanical and neuromuscular control strategies, which has immediate implications for the significance of WB tests in contrast to FS balance tests. Differences in control strategies will also have implications for the understanding of mechanisms for rehabilitation training using such devices. Copyright © 2015. Published by Elsevier B.V.

  12. Intra and intersession reliability of balance measures during one-leg standing in young adults.

    Science.gov (United States)

    Muehlbauer, Thomas; Roth, Ralf; Mueller, Sylvana; Granacher, Urs

    2011-08-01

    A study was designed to investigate the intra and intersession reliability during 1-leg standing recorded from a computerized balance platform. Thirty-nine healthy young men (n = 17, age range: 20-30 years) and women (n = 22, age range: 21-28 years) performed 3 testing sessions, with the second session 30 minutes (intrasession comparison) and the third session 1 week (intersession comparison) after the initial testing session. Within each testing session, participants completed 3 trials of 1-leg standing with their dominant leg. Reliability statistics were calculated using the mean of all 3 trials during each session for 6 balance measures (i.e., total displacements of the center of pressure [CoP], the CoP displacements in mediolateral and anterior-posterior directions, and the CoP speed and CoP area and their SD). Test-retest reliability was examined calculating both, intraclass correlation coefficient (ICC) with 95% confidence interval (95% CI) and Bland-Altman plots. In both sexes and irrespective of balance measure, ICC values were ≥0.75 except for 1 parameter in men. This indicates an excellent intra and intersession reliability. Bland-Altman plots confirmed these findings by showing that only 1 or 2 (4.5-11.8%) of the data points were beyond the 95% CI. Practitioners and clinicians are provided with a posturographic test setup that proved to be reliable. Researchers can use these data to identify the range in which the true value of a subject's score lies and estimate a priori sample sizes.

  13. The effects of passive leg press training on jumping performance, speed, and muscle power.

    Science.gov (United States)

    Liu, Chiang; Chen, Chuan-Shou; Ho, Wei-Hua; Füle, Róbert János; Chung, Pao-Hung; Shiang, Tzyy-Yuang

    2013-06-01

    Passive leg press (PLP) training was developed based on the concepts of the stretch-shortening cycle (SSC) and the benefits of high muscle contraction velocity. Passive leg press training enables lower limb muscle groups to apply a maximum downward force against a platform moved up and down at high frequency by an electric motor. Thus, these muscle groups accomplished both concentric and eccentric isokinetic contractions in a passive, rapid, and repetitive manner. This study investigates the effects of 10 weeks of PLP training at high and low movement frequencies have on jumping performance, speed, and muscle power. The authors selected 30 college students who had not performed systematic resistance training in the previous 6 months, including traditional resistance training at a squat frequency of 0.5 Hz, PLP training at a low frequency of 0.5 Hz, and PLP training at a high frequency of 2.5 Hz, and randomly divided them into 3 groups (n = 10). The participants' vertical jump, drop jump, 30-m sprint performance, explosive force, and SSC efficiency were tested under the same experimental procedures at pre- and post-training. Results reveal that high-frequency PLP training significantly increased participants' vertical jump, drop jump, 30-m sprint performance, instantaneous force, peak power, and SSC efficiency (p training (p training significantly increased participants' vertical jump, 30-m sprint performance, instantaneous force, and peak power (p training only increased participants' 30-m sprint performance and peak power (p training at high movement frequency. A PLP training machine powered by an electrical motor enables muscles of the lower extremities to contract faster compared with voluntary contraction. Therefore, muscle training with high contraction velocity is one of the main methods of increasing muscle power. Passive leg press training is a unique method for enhancing jump performance, speed, and muscle power.

  14. Shape accuracy optimization for cable-rib tension deployable antenna structure with tensioned cables

    Science.gov (United States)

    Liu, Ruiwei; Guo, Hongwei; Liu, Rongqiang; Wang, Hongxiang; Tang, Dewei; Song, Xiaoke

    2017-11-01

    Shape accuracy is of substantial importance in deployable structures as the demand for large-scale deployable structures in various fields, especially in aerospace engineering, increases. The main purpose of this paper is to present a shape accuracy optimization method to find the optimal pretensions for the desired shape of cable-rib tension deployable antenna structure with tensioned cables. First, an analysis model of the deployable structure is established by using finite element method. In this model, geometrical nonlinearity is considered for the cable element and beam element. Flexible deformations of the deployable structure under the action of cable network and tensioned cables are subsequently analyzed separately. Moreover, the influence of pretension of tensioned cables on natural frequencies is studied. Based on the results, a genetic algorithm is used to find a set of reasonable pretension and thus minimize structural deformation under the first natural frequency constraint. Finally, numerical simulations are presented to analyze the deployable structure under two kinds of constraints. Results show that the shape accuracy and natural frequencies of deployable structure can be effectively improved by pretension optimization.

  15. Jamming of Knots along a Tensioned Chain

    Science.gov (United States)

    Doyle, Patrick; Narsimhan, Vivek; Renner, C. Benjamin

    In the limit of very long chains, coiled polymers almost always self-entangle and form knots. In this study, we characterize the motion of these knots along the chain contour when the chain is under very high tension. In this regime, we find that the knot exhibits glassy physics. For example, instead of moving continuously along the contour, the knot becomes kinetically trapped in long-lived, metastable states. This caging phenomenon follows Poisson statistics, and thus the long-time dynamics of the knot are diffusive. We quantify the long-time diffusivity of knots of various topologies, and we find that the diffusivity decays exponentially with increasing chain tension. The rate-of-decay of these transport properties is relatively insensitive to the knot's topology, which can be explained by examining the energy landscape of the self-reptation moves of the knot along the chain. Finally, we examine the role of bending and excluded volume interactions on this jamming phenomenon. Bending plays the biggest role in determining the onset of jamming, but the corrugation of the excluded volume interactions solely determines the rate-of-decay of the knot's transport properties. Now at Liquiglide.

  16. Single leg balancing in ballet: effects of shoe conditions and poses.

    Science.gov (United States)

    Lobo da Costa, Paula H; Azevedo Nora, Fernanda G S; Vieira, Marcus Fraga; Bosch, Kerstin; Rosenbaum, Dieter

    2013-03-01

    The purpose of this study was to describe the effects of lower limb positioning and shoe conditions on stability levels of selected single leg ballet poses performed in demi-pointe position. Fourteen female non-professional ballet dancers (mean age of 18.4±2.8 years and mean body mass index of 21.5±2.8kg/m(2)) who had practiced ballet for at least seven years, without any musculoskeletal impairment volunteered to participate in this study. A capacitive pressure platform allowed for the assessment of center of pressure variables related to the execution of three single leg ballet poses in demi pointé position: attitude devant, attitude derriére, and attitude a la second. Peak pressures, contact areas, COP oscillation areas, anterior-posterior and medio-lateral COP oscillations and velocities were compared between two shoe conditions (barefoot versus slippers) and among the different poses. Barefoot performances produced more stable poses with significantly higher plantar contact areas, smaller COP oscillation areas and smaller anterior-posterior COP oscillations. COP oscillation areas, anterior-posterior COP oscillations and medio-lateral COP velocities indicated that attitude a la second is the least challenging and attitude derriére the most challenging pose. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Biomechanical strategies implemented to compensate for mild leg length discrepancy during gait.

    Science.gov (United States)

    Resende, Renan A; Kirkwood, Renata N; Deluzio, Kevin J; Cabral, Silvia; Fonseca, Sérgio T

    2016-05-01

    Although mild leg length discrepancy is related to lower limb injuries, there is no consensus regarding its effects on the biomechanics of the lower limbs during gait. Biomechanical data of 19 healthy participants were collected while they walked under different conditions as described: (1) control condition-wearing flat thick sandals; (2) short limb condition-wearing a flat thick sandal on the left and a flat thin sandal on the right foot; (3) long limb condition: wearing flat thin sandal on the left and flat thick sandal on the right foot. The thick and thin sandals had 1.45cm of mean thickness difference. The right lower limb data were analyzed for all conditions. Ankle, knee, hip and pelvis kinematics and internal moments were measured with a motion capture system and six force platforms. Principal component analysis was used to compare differences between conditions. The scores of the principal components were compared between conditions using one-way repeated measures ANOVA. Twelve gait variables were different between conditions: rearfoot dorsiflexion and inversion (pgait, apparently to equalize the functional length of the lower limbs. However, these strategies did not fully succeed, since both short and long limb conditions affected pelvic motion in the frontal plane. These results suggest that mild leg length discrepancy should not be overlooked in clinical settings. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Postural control in restless legs syndrome with medication intervention using pramipexole.

    Science.gov (United States)

    Ahlgrén-Rimpiläinen, Aulikki; Lauerma, Hannu; Kähkönen, Seppo; Aalto, Heikki; Tuisku, Katinka; Holi, Matti; Pyykkö, Ilmari; Rimpiläinen, Ilpo

    2014-02-01

    Central dopamine regulation is involved in postural control and in the pathophysiology of restless legs syndrome (RLS) and Parkinson's disease (PD). Postural control abnormalities have been detected in PD, but there are no earlier studies with regard to RLS and postural control. Computerized force platform posturography was applied to measure the shift and the velocity (CPFV) of center point of forces (CPF) with eyes open (EO) and eyes closed (EC) in controls (n = 12) and prior and after a single day intervention with pramipexole in RLS subjects (n = 12). CPFV (EO) was significantly lower in the RLS group (p postural stability. Further research is needed to clarify altered feedback in the central nervous system and involvement of dopamine and vision in the postural control in RLS.

  19. Parameters Sensitivity Analysis of Position-Based Impedance Control for Bionic Legged Robots’ HDU

    Directory of Open Access Journals (Sweden)

    Kaixian Ba

    2017-10-01

    Full Text Available For the hydraulic drive unit (HDU on the joints of bionic legged robots, this paper proposes the position-based impedance control method. Then, the impedance control performance is tested by a HDU performance test platform. Further, the method of first-order sensitivity matrix is proposed to analyze the dynamic sensitivity of four main control parameters under four working conditions. To research the parameter sensitivity quantificationally, two sensitivity indexes are defined, and the sensitivity analysis results are verified by experiments. The results of the experiments show that, when combined with corresponding optimization strategies, the dynamic compliance composition theory and the results from sensitivity analysis can compensate for the control parameters and optimize the control performance in different working conditions.

  20. Postural control during one-leg stance in active and sedentary older people

    Directory of Open Access Journals (Sweden)

    Leonardo George Victorio Victor

    2014-09-01

    Full Text Available Physical inactivity and aging are functional disability factors for older individuals, causing loss of balance and increasing the risk of falls. The purpose of this study was to compare the balance of physically independent older individuals, both participants and non-participants in a regular exercise program. Fifty six physically independent older participants were divided into G1ACTIVE = 28 individuals who participate in a regular exercise program and G2SEDENTARY = 28 individuals who did not participate in any physical exercise program. All participants underwent an eyes-open during one-leg balance test on a force platform. The postural oscillation parameters included center of pressure (COP; sway mean velocity and frequency of COP oscillations. G2 SEDENTARY showed higher postural instability than G1ACTIVE. Significant differences were observed for the main balance parameters. The results of this study support the concept that participation in regular physical activity is beneficial for postural balance of older individuals.

  1. Well-leg compartment syndrome after gynecological laparoscopic surgery

    DEFF Research Database (Denmark)

    Boesgaard-Kjer, Diana H; Boesgaard-Kjer, Daniel; Kjer, Jens Jørgen

    2013-01-01

    Well-leg compartment syndrome in the lower extremities after surgery in the lithotomy position is a rare but severe complication requiring early diagnosis and intervention. Several circumstances predispose to this condition as a consequence of increased intra-compartmental pressure......, such as positioning of the legs during operation (lithotomy and Lloyd-Davies positions), a prolonged operation, external compression and vascular insults, both pre- and intra-operatively. To prevent well-leg compartment syndrome it is important to improve knowledge of the condition among surgeons and nursing staff....... Potential risk factors and preventive initiatives are listed to reduce the risk in future patients. We describe two patients who underwent gynecologic laparoscopic surgery and postoperatively developed well-leg compartment syndrome....

  2. Hereditary Lymphedema of the Leg – A Case Report

    Directory of Open Access Journals (Sweden)

    Birgit Heinig

    2017-07-01

    Full Text Available Primary of hereditary lymphedema is a rare but progressive disease. It is yet not curable. We present a 48-year-old male patient with hereditary lymphedema of his left leg, that was realised by minor trauma (able twist when he was seven years old. He had never been treated for lymphedema but experienced multiple erysipelas during his life. After diagnostic procedures to exclude other causes of leg swelling, the diagnosis of hereditary lymphedema of the leg, stage III was confirmed. We initialized complex decongestive therapy. During two weeks of intensive treatment, the circumference of the left leg could be reduced by 10 cm. This case illustrates the "natural course" hereditary lymphedema. But it raises the hope that even after decades of ignorance, the patients benefits from complex decongestive treatment. Therapeutic nihilism is unnecessary and poses lymphedema patients to risks of infection and secondary malignancies like Stewart-Trewes syndrome.

  3. Delivery of Compression Therapy for Venous Leg Ulcers

    DEFF Research Database (Denmark)

    Zarchi, Kian; Jemec, Gregor B E

    2014-01-01

    IMPORTANCE: Despite the documented effect of compression therapy in clinical studies and its widespread prescription, treatment of venous leg ulcers is often prolonged and recurrence rates high. Data on provided compression therapy are limited. OBJECTIVE: To assess whether home care nurses achieve...... adequate subbandage pressure when treating patients with venous leg ulcers and the factors that predict the ability to achieve optimal pressure. DESIGN, SETTING, AND PARTICIPANTS: We performed a cross-sectional study from March 1, 2011, through March 31, 2012, in home care centers in 2 Danish...... with venous leg ulcers do not receive adequate compression therapy. Training programs that focus on practical bandaging skills should be implemented to improve management of venous leg ulcers....

  4. Lower leg electrical impedance after distal bypass surgery

    DEFF Research Database (Denmark)

    Belanger, G K; Bolbjerg, M L; Heegaard, N H

    1998-01-01

    Electrical impedance was determined in 13 patients following distal bypass surgery to evaluate lower leg oedema as reflected by its circumference. Tissue injury was assessed by the plasma concentration of muscle enzymes. After surgery, the volume of the control lower leg increased from 1250 (816......-104) ohms (P surgery was indicated by an increase in total creatine kinase (n = 17) and MB isoenzyme of creatine kinase (n = 8) (P surgery (P ... of troponin I (n = 8). In conclusion, tissue injury was reflected by increases in muscle enzymes in plasma. We found an inverse correlation between lower leg electrical impedance and volume, but the deviation in electrical impedance was approximately twice that of the leg volume. Electrical impedance appears...

  5. Eyelash Transplantation Using Leg Hair by Follicular Unit Extraction

    Directory of Open Access Journals (Sweden)

    Sanusi Umar, MD

    2015-03-01

    Full Text Available Summary: Fine hairs of the head and nape areas have been used as donor sources in eyelash transplantation but are straight, coarse, and grow rapidly, requiring frequent eyelash maintenance. This is the first reported case of eyelash transplantation by follicular unit extraction using leg hair as a donor source; findings were compared with that of another patient who underwent a similar procedure with donor hairs from the nape area. Although both patients reported marked improvement in fullness of eyelashes within 3 months postsurgery, the transplanted leg hair eyelashes required less frequent trimming (every 5–6 weeks compared with nape hair eyelashes (every 2–3 weeks. Additionally, in leg hair eyelashes, the need for perming to sustain a natural looking eyelash curl was eliminated. Eyelash transplantation using leg donor hair in hirsute women may result in good cosmetic outcomes and require less maintenance compared with nape donor hair.

  6. Quality of Life in People with Leg Ulcer, Integrative Review

    Directory of Open Access Journals (Sweden)

    Daniela Alves

    2016-04-01

    Full Text Available Objective: To identify the main changes in the daily life of people with leg ulcer and how that affects the person’s quality of life. Methodology: We used the methodology PI [C] OD and selected four research articles, taken from EBSCO, PubMed, and EWMA. Results: The main changes identified in the people’s daily live with leg ulcers are physical (pain, decreased mobility, presence of exudate, bad smell from the wound and change in the style of clothing, psychological (sleep disorders, depression, anxiety, feelings of rejection and low self-steem, social (isolation, restriction in leisure activities, inability to perform household chores. Conclusions: The literature about the person’s quality of life with leg ulcer reported a significant impact in the daily life. The care provided by nurses should be centered on the person, integrating all the kind of needs and the leg ulcer must not be the sole focus of care

  7. Periodic Limb Movement Disorder (PLMD) and Restless Legs Syndrome (RLS)

    Science.gov (United States)

    ... the syndrome. Risk factors include the following: A sedentary lifestyle Smoking Obesity Many people with narcolepsy or rapid eye movement (REM) behavior disorder move their legs periodically during sleep. Both ...

  8. Leg and arm lactate and substrate kinetics during exercise

    DEFF Research Database (Denmark)

    Van Hall, Gerrit; Jensen-Urstad, M; Rosdahl, H

    2003-01-01

    To study the role of muscle mass and muscle activity on lactate and energy kinetics during exercise, whole body and limb lactate, glucose, and fatty acid fluxes were determined in six elite cross-country skiers during roller-skiing for 40 min with the diagonal stride (Continuous Arm + Leg) followed...... by 10 min of double poling and diagonal stride at 72-76% maximal O(2) uptake. A high lactate appearance rate (R(a), 184 +/- 17 micromol x kg(-1) x min(-1)) but a low arterial lactate concentration ( approximately 2.5 mmol/l) were observed during Continuous Arm + Leg despite a substantial net lactate...... release by the arm of approximately 2.1 mmol/min, which was balanced by a similar net lactate uptake by the leg. Whole body and limb lactate oxidation during Continuous Arm + Leg was approximately 45% at rest and approximately 95% of disappearance rate and limb lactate uptake, respectively. Limb lactate...

  9. California Red-Legged Frogs in coastal dune drainages (2015)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — California Red-legged Frogs (Rana draytonii) are typically regarded as inhabitants of permanent ponds, marshes, and slow-moving streams, but their ecology in other...

  10. Effect of respiratory physiotherapy on arterial oxygen tension.

    Science.gov (United States)

    Hedstrand, U; Liw, M; Rooth, G; Ogren, C H

    1978-01-01

    The effect of deep breathing on arterial oxygen tension was investigated in 45 postoperative patients. Arterial oxygen tension was estimated by the transcutaneous oxygen tension method, which allows continuous non-invasive measurement of the arterial oxygen tension changes. Three deep breaths in 1 min, assisted by three respiratory therapy devices, were compared to a standard physiotherapy programme. A peak increase in arterial oxygen tension of 3--4.5 mmHg occurred after 1 min, and significantly increased values were seen for 2--4 min following deep breathing with the three respiratory devices. From the various physiotherapeutic procedures, verbally and manually assisted deep breathing gave a 7 mmHg PO2 peak and significantly increased values for 6 min. The sign mechanism is discussed in the light of the present knowledge of airway closure, which gives a satisfactory explanation of the short-lasting increase in oxygen tension.

  11. Mobile Platforms and Development Environments

    CERN Document Server

    Helal, Sumi; Li, Wengdong

    2012-01-01

    Mobile platform development has lately become a technological war zone with extremely dynamic and fluid movement, especially in the smart phone and tablet market space. This Synthesis lecture is a guide to the latest developments of the key mobile platforms that are shaping the mobile platform industry. The book covers the three currently dominant native platforms -- iOS, Android and Windows Phone -- along with the device-agnostic HTML5 mobile web platform. The lecture also covers location-based services (LBS) which can be considered as a platform in its own right. The lecture utilizes a sampl

  12. Acupuncture for the prevention of tension-type headache

    Science.gov (United States)

    Linde, Klaus; Allais, Gianni; Brinkhaus, Benno; Fei, Yutong; Mehring, Michael; Shin, Byung-Cheul; Vickers, Andrew; White, Adrian R

    2016-01-01

    Background Acupuncture is often used for prevention of tension-type headache but its effectiveness is still controversial. This is an update of our Cochrane review originally published in Issue 1, 2009 of The Cochrane Library. Objectives To investigate whether acupuncture is a) more effective than no prophylactic treatment/routine care only; b) more effective than ‘sham’ (placebo) acupuncture; and c) as effective as other interventions in reducing headache frequency in adults with episodic or chronic tension-type headache. Search methods We searched CENTRAL, MEDLINE, EMBASE and AMED to 19 January 2016. We searched the World Health Organization (WHO) International Clinical Trials Registry Platform to 10 February 2016 for ongoing and unpublished trials. Selection criteria We included randomised trials with a post-randomisation observation period of at least eight weeks, which compared the clinical effects of an acupuncture intervention with a control (treatment of acute headaches only or routine care), a sham acupuncture intervention or another prophylactic intervention in adults with episodic or chronic tension-type headache. Data collection and analysis Two review authors checked eligibility; extracted information on participants, interventions, methods and results; and assessed study risk of bias and the quality of the acupuncture intervention. The main efficacy outcome measure was response (at least 50% reduction of headache frequency) after completion of treatment (three to four months after randomisation). To assess safety/acceptability we extracted the number of participants dropping out due to adverse effects and the number of participants reporting adverse effects. We assessed the quality of the evidence using GRADE (Grading of Recommendations Assessment, Development and Evaluation). Main results Twelve trials (11 included in the previous version and one newly identified) with 2349 participants (median 56, range 10 to 1265) met the inclusion criteria

  13. The relationship between Restless legs Syndrome and opioid abuserelapse

    OpenAIRE

    Hamideh Moosavi Saadatabadi

    2016-01-01

    Restless Legs Syndrome (RLS) is a sensory-motor neurological disorder that overallyaffects about 10 percent of adults. RLS can be correlated with opioid abuse relapse and considered as a risk factor in relapse of opioid abuse . This study aimedto investigate the relationship between restless legs syndrome and opioid use relapse.In this crosssectional study participants included 214 patients with opioid abuse referred to Tehran Psychiatric Institute for substance abuse treatment in 2015.After ...

  14. Fatal pox infection in a rough-legged hawk

    Science.gov (United States)

    Pearson, G.L.; Pass, D.A.; Beggs, E.C.

    1975-01-01

    Natural pox infection occurred in a free-living rough-legged hawk (Buteo lagopus) in northeastern North Dakota. Gross, histological and electron microscopic findings were typical of pox infection, and characteristic lesions developed in red-tailed hawks (Buteo jamaicensis) but not in great horned owls (Bubo virginianus) following inoculation with case material. Death of the rough-legged hawk was attributed to starvation resulting from inability to capture prey and to blood loss from foot lesions.

  15. Common causes of lower leg pain an Athletes

    OpenAIRE

    Pešková, Lucie

    2011-01-01

    An exercise-induced leg pain resulting from chronic overloading is a common condition affecting physically active population. This bachelor thesis gives an overview of recent knowledge in differential diagnosis of a chronic lower leg pain. Theoretic aspects deal with three main conditions with the highest incidence, including stress fractures, medial tibial stress syndrome and chronic exertional compartment syndrome. Particular chapters describe the difference in the epidemiology, aetiology, ...

  16. Hysteretic behavior of a belt tensioner: modeling and experimental investigation

    OpenAIRE

    Michon, Guilhem; Manin, Lionel; Dufour, Regis

    2005-01-01

    In this paper we describe the modeling of the hysteretic behavior of belt tensioners. An initial experimental device is composed only of the tensioner by using forcing frequencies, preloads and deflection amplitudes. It permits the identification of the parameters of the restoring force model used. Comparison of the measured and predicted force deflection loops of the tensioner subjected to large deflections permits preliminary validation of the model.The second experimental device consists o...

  17. Automatic Tension Adjuster For Flexible-Shaft Grinder

    Science.gov (United States)

    Burley, Richard K.; Hoult, William S.

    1990-01-01

    Flexible shaft of grinding tool automatically maintained in tension by air pressure. Probelike tool bent to reach hard-to-reach areas for grinding and polishing. Unless shaft held in tension, however, it rubs against its sheath, overheating and wearing out quickly. By taking up slack in flexible cable, tension adjuster reduces friction and enables tool to operate more efficiently, in addition to lengthening operating life.

  18. Straight leg elevation to rule out pelvic injury.

    Science.gov (United States)

    Bolt, Caroline; O'Keeffe, Francis; Finnegan, Pete; Dickson, Kristofer; Smit, De Villiers; Fitzgerald, Mark C; Mitra, Biswadev

    2017-10-09

    Pelvic x-ray is frequently used as a screening tool during initial assessment of injured patients. However routine use in the awake and alert blunt trauma patient may be questioned due to low yield. We propose a clinical tool that may avoid unnecessary imaging by examining whether the ability to straight leg raise, without pain, can rule out pelvic injury. We conducted a prospective cohort study with the exposure variables of ability to straight leg raise and presence of pain on doing so, and presence of pelvic fracture on x-ray as the primary outcome variable. Of the 328 participants, 35 had pelvic fractures, and of these 32 were either unable to straight leg raise, or had pain on doing so, with a sensitivity of 91.43% (95% CI: 76.94-98.2%) and a negative predictive value of 98.57% (95% CI: 95.88-99.70%). The 3 participants with a pelvic fracture who could straight leg raise with no pain, all had a GCS of less than 15, and therefore, among the sub-group of patients with GCS15, a 100% sensitivity and 100% negative predictive value for straight leg raise with no pain to rule out pelvic fracture was demonstrated. Among awake, alert patients, painless straight leg raise can exclude pelvic fractures and be incorporated into initial examination during reception and resuscitation of injured patients. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  19. Modeling posture-dependent leg actuation in sagittal plane locomotion

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, J [Department of Mechanical Engineering, Oregon State University, Corvallis, OR 97331 (United States); Clark, J, E-mail: schmitjo@engr.orst.ed [Department of Mechanical Engineering, Florida State University, Tallahassee, FL 32310 (United States)

    2009-12-15

    The spring loaded inverted pendulum template has been shown to accurately model the steady locomotion dynamics of a variety of running animals, and has served as the inspiration for an entire class of dynamic running robots. While the template models the leg dynamics by an energy-conserving spring, insects and animals have structures that dissipate, store and produce energy during a stance phase. Recent investigations into the spring-like properties of limbs, as well as animal response to drop-step perturbations, suggest that animals use their legs to manage energy storage and dissipation, and that this management is important for gait stability. In this paper, we extend our previous analysis of control of the spring loaded inverted pendulum template via changes in the leg touch-down angle to include energy variations during the stance phase. Energy variations are incorporated through leg actuation that varies the force-free leg length during the stance phase, yet maintains qualitatively correct force and velocity profiles. In contrast to the partially asymptotically stable gaits identified in previous analyses, incorporating energy and leg angle variations in this manner produces complete asymptotic stability. Drop-step perturbation simulations reveal that the control strategy is rather robust, with gaits recovering from drops of up to 30% of the nominal hip height.

  20. Force feedback reinforces muscle synergies in insect legs.

    Science.gov (United States)

    Zill, Sasha N; Chaudhry, Sumaiya; Büschges, Ansgar; Schmitz, Josef

    2015-11-01

    The nervous system solves complex biomechanical problems by activating muscles in modular, synergist groups. We have studied how force feedback in substrate grip is integrated with effects of sense organs that monitor support and propulsion in insects. Campaniform sensilla are mechanoreceptors that encode forces as cuticular strains. We tested the hypothesis that integration of force feedback from receptors of different leg segments during grip occurs through activation of specific muscle synergies. We characterized the effects of campaniform sensilla of the feet (tarsi) and proximal segments (trochanter and femur) on activities of leg muscles in stick insects and cockroaches. In both species, mechanical stimulation of tarsal sensilla activated the leg muscle that generates substrate grip (retractor unguis), as well as proximal leg muscles that produce inward pull (tibial flexor) and support/propulsion (trochanteral depressor). Stimulation of campaniform sensilla on proximal leg segments activated the same synergistic group of muscles. In stick insects, the effects of proximal receptors on distal leg muscles changed and were greatly enhanced when animals made active searching movements. In insects, the task-specific reinforcement of muscle synergies can ensure that substrate adhesion is rapidly established after substrate contact to provide a stable point for force generation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Surgical management of exertional anterior compartment syndrome of the leg.

    Science.gov (United States)

    Ali, T; Mohammed, F; Mencia, M; Maharaj, D; Hoford, R

    2013-07-01

    To describe the characteristic presentation of exertional leg pain in athletes and to discuss the diagnostic options and surgical management of exertional anterior compartment syndrome of the leg in this group of patients. Data from a series of athletes presenting with exertional leg pain were analysed and categorized according to aetiology. Sixty-six athletes presenting with exertional leg pain in 102 limbs were analysed. Sixteen patients in a first group of 20 patients with a provisional diagnosis of exertional anterior compartment syndrome of the leg underwent a closed fasciotomy with complete resolution of symptoms. A second group of 42 patients were diagnosed as medial tibial stress syndrome and a third group of four patients had confirmed stress fracture of the tibia. Exertional leg pain is a common presenting complaint of athletes to sports physicians and physiotherapists. Careful analysis can lead to an accurate diagnosis and commencement of effective treatment. Exertional anterior compartment syndrome can be successfully treated utilizing a closed fasciotomy with a rapid return to sport.

  2. Tension stiffening of steel-fiber-reinforced concrete

    Directory of Open Access Journals (Sweden)

    Luiz Álvaro Oliveira Júnior

    2016-08-01

    Full Text Available In this paper, the mechanical behavior of steel-fiber-reinforced concrete was investigated to analyze the influence of steel fibers on tension stiffening. Using tension tests, the tension stiffening coefficient was evaluated through the load versus strain responses obtained from strain gages fixed to reinforcement steels. Moreover, an empirical model is proposed to estimate the tension stiffening coefficient of steel-fiber-reinforced concrete from reinforcement strains. From the test results, it was verified that the addition of steel fibers to concrete reduced the reinforcement steel strains and the crack width and increased the stiffness of cracked concrete, mainly in concretes reinforced with highvolumesof fibers.

  3. Common tester platform concept.

    Energy Technology Data Exchange (ETDEWEB)

    Hurst, Michael James

    2008-05-01

    This report summarizes the results of a case study on the doctrine of a common tester platform, a concept of a standardized platform that can be applicable across the broad spectrum of testing requirements throughout the various stages of a weapons program, as well as across the various weapons programs. The common tester concept strives to define an affordable, next-generation design that will meet testing requirements with the flexibility to grow and expand; supporting the initial development stages of a weapons program through to the final production and surveillance stages. This report discusses a concept investing key leveraging technologies and operational concepts combined with prototype tester-development experiences and practical lessons learned gleaned from past weapons programs.

  4. Available: motorised platform

    CERN Multimedia

    The COMPASS collaboration

    2014-01-01

    The COMPASS collaboration would like to offer to a new owner the following useful and fully operational piece of equipment, which is due to be replaced with better adapted equipment.   Please contact Erwin Bielert (erwin.bielert@cern.ch or 160539) for further information.  Motorized platform (FOR FREE):   Fabricated by ACL (Alfredo Cardoso & Cia Ltd) in Portugal. The model number is MeXs 5-­‐30.  Specifications: 5 m wide, 1 m deep, adjustable height (1.5 m if folded). Maximum working floor height: 4 m. conforms to CERN regulations, number LV158. Type LD500, capacity 500 kg and weight 2000 kg.  If no interested party is found before December 2014, the platform will be thrown away.

  5. Cloud Robotics Platforms

    Directory of Open Access Journals (Sweden)

    Busra Koken

    2015-01-01

    Full Text Available Cloud robotics is a rapidly evolving field that allows robots to offload computation-intensive and storage-intensive jobs into the cloud. Robots are limited in terms of computational capacity, memory and storage. Cloud provides unlimited computation power, memory, storage and especially collaboration opportunity. Cloud-enabled robots are divided into two categories as standalone and networked robots. This article surveys cloud robotic platforms, standalone and networked robotic works such as grasping, simultaneous localization and mapping (SLAM and monitoring.

  6. HPC - Platforms Penta Chart

    Energy Technology Data Exchange (ETDEWEB)

    Trujillo, Angelina Michelle [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-10-08

    Strategy, Planning, Acquiring- very large scale computing platforms come and go and planning for immensely scalable machines often precedes actual procurement by 3 years. Procurement can be another year or more. Integration- After Acquisition, machines must be integrated into the computing environments at LANL. Connection to scalable storage via large scale storage networking, assuring correct and secure operations. Management and Utilization – Ongoing operations, maintenance, and trouble shooting of the hardware and systems software at massive scale is required.

  7. A Behavioral Mechanism of How Increases in Leg Strength Improve Old Adults' Gait Speed

    NARCIS (Netherlands)

    Uematsu, Azusa; Tsuchiya, Kazushi; Kadono, Norio; Kobayashi, Hirofumi; Kaetsu, Takamasa; Hortobagyi, Tibor; Suzuki, Shuji

    2014-01-01

    We examined a behavioral mechanism of how increases in leg strength improve healthy old adults' gait speed. Leg press strength training improved maximal leg press load 40% (p = 0.001) and isometric strength in 5 group of leg muscles 32% (p = 0.001) in a randomly allocated intervention group of

  8. Venous leg ulcer patients: a review of the literature on lifestyle and pain-related interventions.

    NARCIS (Netherlands)

    Heinen, M.M.; Achterberg, T. van; Reimer, W.S. op; Kerkhof, P.C.M. van de; Laat, H.E.W. de

    2004-01-01

    BACKGROUND: Having a leg ulcer has a major impact on daily life. Lifestyle is mentioned in most leg ulcer guidelines but mostly without much emphasis on the subject. AIMS AND OBJECTIVES: Evidence for the effect of nutrition, leg elevation and exercise on the healing of leg ulcers was reconsidered.

  9. "Platform switching": serendipity.

    Science.gov (United States)

    Kalavathy, N; Sridevi, J; Gehlot, Roshni; Kumar, Santosh

    2014-01-01

    Implant dentistry is the latest developing field in terms of clinical techniques, research, material science and oral rehabilitation. Extensive work is being done to improve the designing of implants in order to achieve better esthetics and function. The main drawback with respect to implant restoration is achieving good osseointegration along with satisfactory stress distribution, which in turn will improve the prognosis of implant prosthesis by reducing the crestal bone loss. Many concepts have been developed with reference to surface coating of implants, surgical techniques for implant placement, immediate and delayed loading, platform switching concept, etc. This article has made an attempt to review the concept of platform switching was in fact revealed accidentally due to the nonavailability of the abutment appropriate to the size of the implant placed. A few aspect of platform switching, an upcoming idea to reduce crestal bone loss have been covered. The various methods used for locating and preparing the data were done through textbooks, Google search and related articles.

  10. "Platform switching": Serendipity

    Directory of Open Access Journals (Sweden)

    N Kalavathy

    2014-01-01

    Full Text Available Implant dentistry is the latest developing field in terms of clinical techniques, research, material science and oral rehabilitation. Extensive work is being done to improve the designing of implants in order to achieve better esthetics and function. The main drawback with respect to implant restoration is achieving good osseointegration along with satisfactory stress distribution, which in turn will improve the prognosis of implant prosthesis by reducing the crestal bone loss. Many concepts have been developed with reference to surface coating of implants, surgical techniques for implant placement, immediate and delayed loading, platform switching concept, etc. This article has made an attempt to review the concept of platform switching was in fact revealed accidentally due to the nonavailability of the abutment appropriate to the size of the implant placed. A few aspect of platform switching, an upcoming idea to reduce crestal bone loss have been covered. The various methods used for locating and preparing the data were done through textbooks, Google search and related articles.

  11. Position Measurement/Tracking Comparison of the Instrumentation in a Droplet-Actuated-Robotic Platform

    Directory of Open Access Journals (Sweden)

    Pierre Lambert

    2013-05-01

    Full Text Available This paper reports our work on developing a surface tension actuated micro-robotic platform supported by three bubbles (liquid environment or droplets (gaseous environment. The actuation principle relies on the force developed by surface tension below a millimeter, which benefits from scaling laws, and is used to actuate this new type of compliant robot. By separately controlling the pressure inside each bubble, three degrees of freedom can be actuated. We investigated three sensing solutions to measure the platform attitude in real-time (z-position of each droplet, leading to the knowledge of the z position and Θx and Θy tilts of the platform. The comparison between optical, resistive, and capacitive measurement principles is hereafter reported. The optical technique uses SFH-9201 components. The resistive technique involves measuring the electrical resistance of a path flowing through two droplets and the platform. This innovative technique for sensing table position combines three pairs of resistances, from which the resistance in each drop can be deduced, thus determining the platform position. The third solution is a more usual high frequency (~200 MHz capacitive measurement. The resistive method has been proven reliable and is simple to implement. This work opens perspectives toward an interesting sensing solution for micro-robotic platforms.

  12. Biaxial tension on polymer in thermoforming range

    Directory of Open Access Journals (Sweden)

    Billon N.

    2010-06-01

    Full Text Available This paper presents an experimental characterization of mechanical properties of a polyethylene terephtalate (PET resin classically used in stretch blow moulding process. We have applied on such a material a well established experimental protocol at CEMEF, including new and relevant biaxial tensile tests. The experimental set-up relative to biaxial tension will be presented and described in a first part of the paper. Furthermore, we will focus on the experimental DMTA preliminary tests which are required to estimate the resin sensibility to temperature and strain rate in linear viscoelasticity domain. Finally, we will be interested in the material large strain behaviour: biaxial tensile results are presented and discussed. Finally, such an experimental approach should allow a relevant modelling of polymer physics and mechanics; this point will not be discussed here because of a lack of time.

  13. The Curriculum. Conceptual and Practical Tensions

    Directory of Open Access Journals (Sweden)

    Ángel Díaz Barriga

    2003-11-01

    Full Text Available The purpose of this essay is to analyze the formation of two currents in the field of curriculum. These currents, over the last century, were visualized in different ways: one which considers the educational project as linked to a system or an educational institution, a perspective expressed in the various proposals to develop study plans and programs; the other, which links it with concepts like everyday life, curriculum as educational practice and curricular reality, which vindicate what is happening in the educational environment, particularly in the classroom. This paper recognizes a meeting of both currents in the origins of the curriculum field in the early twentieth century; at the same time we analyze its evolution marked by mutual discrediting and ignorance that have generated tensions. It reflects on the need to identify the limitations of each current, but also to recognize their successes.

  14. Tension Type Headache: Evaluation of Chronic Type

    Directory of Open Access Journals (Sweden)

    Ömer Karadaş

    2013-11-01

    Full Text Available Tension type headache(TTH which is a primary headache has episodic and chronic forms. Episodic TTH (ETTH can also be frequent-type and non-frequent-type. According to population-based studies, annual prevalence rates are 38.3% for ETTH and 2.2% for chronic TTH (CTTH. Patients can shift between the sub-groups of TTH. In particular, patients with ETTH are at risk of developing CTTH. Peripheral and central nociceptive mechanism are thought to be responsible in occurrence of TTH. Psychiatric disorders are frequently associated with TTH. Although basic and combined analgesics are used in acute treatment and antidepresants are used in prophylaxis, new treatment modalities are needed.

  15. Evolving spacetimes with purely radial tension

    Directory of Open Access Journals (Sweden)

    B. Nasre Esfahani

    2000-12-01

    Full Text Available   In this study time-dependent and spherically symmetric solutions of the Einstein field equations in an anisotropic background with a purely radial tension are presented. There exist three classes of solutions,1 An open spacetime with a wormhole at its center. 2 A conical spacetime. 3 A closed spacetime. These inhomogeneous solutions are reduced to FRW spacetimes in matter-dominated era, asymptotically. Therefore, they can be used to describe local inhomogeneities that are not considered in the standard model. For the wormhole solution. it is explicity shown that the considered matter is non-exotic, that is, it does not violate the energy conditions. Also, static solutions are studied. There is only one static solution,a conical spacetime. In this case, the matter satisfies the energy condition critically.

  16. Tension Tests of Copper Thin Films

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kyung Jo; Kim, Chung Youb [Chonnam Nat’l Univ., Gwangju (Korea, Republic of)

    2017-08-15

    Tension tests for copper thin films with thickness of 12 μm were performed by using a digital image correlation method based on consecutive digital images. When calculating deformation using digital image correlation, a large deformation causes errors in the calculated result. In this study, the calculation procedure was improved to reduce the error, so that the full field deformation and the strain of the specimen could be accurately and directly measured on its surface. From the calculated result, it can be seen that the strain distribution is not uniform and its variation is severe, unlike the distribution in a common bulk specimen. This might result from the surface roughness introduced in the films during the fabrication process by electro-deposition.

  17. Neurotrophic factors in tension-type headache

    Directory of Open Access Journals (Sweden)

    Renan B. Domingues

    2015-05-01

    Full Text Available Neurotrophic factors (NF are involved in pain regulation and a few studies have suggested that they may play a pathophysiological role in primary headaches. The aim of this study was to investigate NF levels in patients with tension type headache (TTH. We carried out a cross sectional study including 48 TTH patients and 48 age and gender matched controls. Beck Depression and Anxiety Inventories, and Headache Impact Test were recorded. Serum levels of NF were determined by ELISA. There were not significant differences between NF levels between TTH patients and controls. Patients with chronic and episodic TTH had not significant differences in NF levels. The presence of headache at the time of evaluation did not significantly alter the levels of NF. Depression and anxiety scores as well as headache impact did not correlate with NF levels. Our study suggest that the serum levels of NF are not altered in TTH.

  18. [Field of tension between psychomatics and psychiatry].

    Science.gov (United States)

    Kurt, H; Büchi, S; Haring, C; Pycha, R

    2012-11-01

    As a medical topic psychosomatic medicine is able to look back on an almost 100-year-old tradition. Nevertheless, questions about its definition, area of application and by whom it should be practiced remains unsolved. This causes considerable tension with the field of psychiatry which has always seen psychosomatic medicine as a subspecialty of its own discipline. In the article, the development and current position of psychosomatic medicine in German speaking countries other than Germany (Austria, Switzerland and South Tyrol) is presented. While psychosomatic care is currently planned and also partially already executed in Austria, psychosomatic medicine in Switzerland is located with general practitioners on the one hand and consultation-liaison psychiatry on the other. After the radical psychiatric reform of the late 1970s in South Tyrol psychosomatic medicine proved to be a means to remove taboos regarding psychiatric institutions and the mentally ill.

  19. Tending the tensions in co-creation

    DEFF Research Database (Denmark)

    Phillips, Louise Jane

    -creation as a process of mutual learning to be valued at least as much as the outcome AND the neoliberal instrumentalisation of creativity in the service of social innovation and economic growth. The papers build on the themes of Knowledge and Power in Collaborative Research: A Reflexive Approach (Phillips, Kristiansen......Across fields of social practice, the harnessing of creativity in collaborative, dialogic processes of knowledge production is championed as a means to empower participants as agents and generate practice change. ‘Collaboration’, ‘dialogue’ and ‘participation’ have become buzzwords with a taken...... et al, Routledge, 2012), adopting a critical, reflexive approach that interrogates the tensions AND is committed to developing co-creative methods....

  20. Tending the tensions in co-creation

    DEFF Research Database (Denmark)

    Phillips, Professor MSO Louise; Nordentoft, Helle Merete; Pedersen, Lektor Christina Hee

    2013-01-01

    -creation as a process of mutual learning to be valued at least as much as the outcome AND the neoliberal instrumentalisation of creativity in the service of social innovation and economic growth. The papers build on the themes of Knowledge and Power in Collaborative Research: A Reflexive Approach (Phillips, Kristiansen......Across fields of social practice, the harnessing of creativity in collaborative, dialogic processes of knowledge production is championed as a means to empower participants as agents and generate practice change. ‘Collaboration’, ‘dialogue’ and ‘participation’ have become buzzwords with a taken...... et al, Routledge, 2012), adopting a critical, reflexive approach that interrogates the tensions AND is committed to developing co-creative methods....

  1. Dopamine agonists for restless legs syndrome.

    Science.gov (United States)

    Scholz, Hanna; Trenkwalder, Claudia; Kohnen, Ralf; Riemann, Dieter; Kriston, Levente; Hornyak, Magdolna

    2011-03-16

    According to clinical guidelines, dopamine agonists are the first-line treatment of restless legs syndrome (RLS). To evaluate efficacy and safety of dopamine agonists for RLS. We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library 2008, Issue 4), MEDLINE, EMBASE, PsycINFO and CINAHL, from January 1985 to December 2008, plus reference lists of articles. We contacted pharmaceutical companies. We included double-blind randomised controlled trials (RCTs) of dopamine agonist treatment versus placebo or other treatment for a period of at least seven days in patients with RLS (≥ 18 years). Outcomes included the International RLS Severity Rating Scale (IRLS), Clinical Global Impressions (CGI-I), polysomnography and self rated sleep quality, quality of life, daytime functioning, and safety parameters. Two reviewers extracted data separately; assessed risk of bias; and contacted pharmaceutical companies and authors for additional information. We collected dropout rates due to adverse events and experience of adverse events. We included 35 placebo controlled and three active controlled RCTs (N = 7365). The mean reduction on the IRLS was -5.7 points lower in dopamine agonist treatment compared to placebo (95% confidence interval (CI) -6.7 to -4.7). Periodic limb movements in sleep per hour of sleep (PLMS-Index; PLMSI) were -22.4/h lower than in placebo (95% CI -27.8 to -16.9). Self rated quality of sleep and disease specific quality of life were improved by a standardised mean difference (SMD) of 0.40 (95% CI 0.33 to 0.47) and 0.34 (95% CI 0.23 to 0.44), respectively. Patients were more likely to drop out (odds ratio (OR) 1.82, 95% CI 1.35 to 2.45) and experienced more adverse events under dopamine agonist treatment than with placebo (OR 1.82, 95% CI 1.59 to 2.08). Visual inspection of forest plots showed the highest efficacy in three studies investigating cabergoline and pergolide (N = 3). Active controlled trials investigated effects of

  2. Effects of tension on vortex-induced vibration (VIV) responses of a long tensioned cylinder in uniform flows

    Science.gov (United States)

    Kang, Ling; Ge, Fei; Wu, Xiaodong; Hong, Youshi

    2017-02-01

    The effects of tension on vortex-induced vibration (VIV) responses for a tension-dominated long cylinder with an aspect ratio of 550 in uniform flows are experimentally investigated in this paper. The results show that elevated tension suppresses fluctuations of maximum displacement with respect to flow velocity and makes chaotic VIV more likely to appear. With respect to periodic VIV, if elevated tension is applied, the dominant vibration frequency in the in-line (IL) direction will switch from a fundamental vibration frequency to twice the value of the fundamental vibration frequency, which results in a ratio of the dominant vibration frequency in the IL direction to that in the cross-flow direction of 2.0. The suppression of the elevated tension in the fluctuation of the maximum displacement causes the axial tension to become an active control parameter for the VIV maximum displacement of a tension-dominated long riser or tether of an engineering structure in deep oceans. However, the axial tension must be optimized before being used since the high dominant vibration frequency due to the elevated tension may unfavorably affect the fatigue life of the riser or tether.

  3. Platform computing powers enterprise grid

    CERN Multimedia

    2002-01-01

    Platform Computing, today announced that the Stanford Linear Accelerator Center is using Platform LSF 5, to carry out groundbreaking research into the origins of the universe. Platform LSF 5 will deliver the mammoth computing power that SLAC's Linear Accelerator needs to process the data associated with intense high-energy physics research (1 page).

  4. Product Platform Screening at LEGO

    DEFF Research Database (Denmark)

    Mortensen, Niels Henrik; Steen Jensen, Thomas; Nielsen, Ole Fiil

    2012-01-01

    Product platforms offer great benefits to companies developing new products in highly competitive markets. Literature describes how a single platform can be designed from a technical point of view, but rarely mentions how the process begins. How do companies identify possible platform candidates...

  5. Contemporary Internet of Things platforms

    OpenAIRE

    Mineraud, Julien; Mazhelis, Oleksiy; Su, Xiang; Tarkoma, Sasu

    2015-01-01

    This document regroups a representative, but non-exhaustive, list of contemporary IoT platforms. The platforms are ordered alphabetically. The aim of this document is to provide the a quick review of current IoT platforms, as well as relevant information.

  6. [Application of the tension skin flap with different shapes in the pedicle of the reverse neurocutaneous island flap].

    Science.gov (United States)

    Li, Meng; Lan, Xu; Zheng, Ping; Liu, Xing-Yan; Gao, Qiu-Ming; Song, Ming-Jia

    2013-08-01

    To investigate the effects of the tension skin flap with different shapes on the transplantation of the reverse neurocutaneous island flap. From January 2006 to January 2012,there were 21 patients in the study (including 15 males and 6 females), and aged from 14 to 58 years old (35 years old on average). Tension skin flaps with different shapes (triangle ,round and ellipse) were used to improve the blood supply of the reverse neurocutaneous island flap. The tension skin flaps in the pedicle were designed triangularly (10 patients), spherically (8 patients) or elliptically (3 patients). There were 5 patients with defects in the hand (the size from 5.0 cm x 2.0 cm to 8.0 cm x 5.0 cm), and 16 patients with defects in the foot and inferior segment of leg, or around the ankle (the size from 6.0 cm x 4.0 cm to 13.0 cm x 7.0 cm). And all the patients were with the tendon and bone exposed. All the flaps were reversal transplanted, including 5 dorsal neurocutaneous flaps of foot, 4 superficial peroneal neurocutaneous flaps, 4 saphenous neurocutaneous flaps, 3 sural neurocutaneous flaps, 2 superficial radial neurocutaneous flaps, 3 lateral neurocutaneous flaps of forearm. And the survival rate, appearance and sensory recovery of the flaps were analyzed. The distant part of the reversed sural neurocutaneous island flap in 1 case necrosized and healed after dressing change. The other flaps survived entirely, and the donor site all healed primarily. The follow-up time was from 3 months to 2 years (averaged 7 months), and all the flaps had recovered pain and warm sensation with perfect appearance. The tension skin flap in the pedicle can enhance the blood supply and promote survival rate of the reverse neurocutaneous island flap, and can also improve its appearance.

  7. The Lively Legs self-management programme increased physical activity and reduced wound days in leg ulcer patients: Results from a randomized controlled trial.

    NARCIS (Netherlands)

    Heinen, M.M.; Borm, G.F.; Vleuten, C.J.M. van der; Evers, A.W.M.; Oostendorp, R.A.B.; Achterberg, T. van

    2012-01-01

    OBJECTIVE: Investigating the effectiveness of the Lively Legs program for promoting adherence with ambulant compression therapy and physical exercise as well as effects on leg ulcer recurrence. DESIGN: A randomized controlled trial. SETTING: Eleven outpatient clinics for dermatology in the

  8. Leg kinematics and kinetics in landing from a single-leg hop for distance. A comparison between dominant and non-dominant leg

    NARCIS (Netherlands)

    van der Harst, J. J.; Gokeler, A.; Hof, A. L.

    Background. Anterior cruciate ligament (ACL) deficiency can be a major problem for athletes and subsequent reconstruction of the ACL may be indicated if a conservative regimen has failed. After ACL reconstruction signs of abnormality in the use of the leg remain for a long time. It is expected that

  9. Necessary Tension in Marine Risers (Continued Tension des colonnes montantes en mer (suite

    Directory of Open Access Journals (Sweden)

    Lubinski A.

    2006-11-01

    Full Text Available A simple, first approximation method for calculating the necessary tension in a marine riser, is presented. This article is a practical supplement ta the one published under the same title in the March-April 1977 issue of Revue de l'Institut Français du Pétrole. On présente dans cet article une méthode simple permettant de calculer en première approximation la tension d'une colonne montante en mer. Cet article est le complément pratique de celui publié sous le même titre dans le numéro mars-avril 1977 de la Revue de l'Institut Français du Pétrole.

  10. Damage development in woven fabric composites during tension-tension fatigue

    DEFF Research Database (Denmark)

    Hansen, U.

    1999-01-01

    Impacted woven fabric composites were tested in tension-tension fatigue. In contrast to results from static testing, the effects of low energy impact damage in a fatigue environment were found to be the critical element leading to failure of the specimen. This difference emphasizes the need...... to identify and understand the fatigue damage mechanism. A relatively new non-destructive inspection technique using infrared thermography was found to be a very useful tool in detecting damage initiation and growth. Furthermore, this technique supplies valuable information to the characterization...... of the operating fatigue damage mechanism(s). Fatigue leads to a degradation of material properties. Consequently, in connection with impact induced local stress raisers, fatigue produces continuously changing non-uniform stress fields because of stress redistribution effects. Other models addressing evolution...

  11. Prior exercise and standing as strategies to circumvent sitting-induced leg endothelial dysfunction

    OpenAIRE

    Morishima, Takuma; Restaino, Robert M.; Walsh, Lauren K.; Kanaley, Jill A.; Padilla, Jaume

    2017-01-01

    We have previously shown that local heating or leg fidgeting can prevent prolonged sitting-induced leg endothelial dysfunction. However, whether physical activity prevents subsequent sitting-induced leg endothelial dysfunction remains unknown. Herein, we tested the hypothesis that sitting-induced leg endothelial dysfunction would be prevented by prior exercise. We also examined if, in the absence of exercise, standing is an effective alternative strategy to sitting for conserving leg endothel...

  12. VENOUS OCULAR BLOOD FLOW IN NORMAL TENSION AND HIGH TENSION GLAUCOMA

    Directory of Open Access Journals (Sweden)

    Natalia I Kurysheva

    2016-04-01

    Full Text Available Purpose: to study the eye’s venous blood flow and the correlation between clinical data and ocular blood flow in normal tension and high tension open angle glaucoma (POAG. Methods: Color Doppler imaging of arterial and venous blood flow was performed on 78 patients with normal tension glaucoma (NTG, 80 patients with high-pressure glaucoma (HPG and 60 control subjects. The statistical analysis included the calculation of the correlation between clinical data and ocular blood flow parameters, as well as Pearson’s correlation coefficient. The threshold P value for statistical significance was 0.05. Results: Ocular blood flow (both arterial and venous was significantly reduced in NTG and HTG, compared to the control group. While the arterial blood flow reduction was more significant in HTG than in NTG, a decrease in venous blood flow had a higher incidence in NTG. In contrast to the control group, POAG patients showed a correlation between clinical data and venous blood flow. The correlation was higher in NTG patients. Conclusions: The results obtained indicate the potential importance of venous blood flow in glaucoma pathogenesis, especially in NTG.

  13. The Cartesian Diver, Surface Tension and the Cheerios Effect

    Science.gov (United States)

    Chen, Chi-Tung; Lee, Wen-Tang; Kao, Sung-Kai

    2014-01-01

    A Cartesian diver can be used to measure the surface tension of a liquid to a certain extent. The surface tension measurement is related to the two critical pressures at which the diver is about to sink and about to emerge. After sinking because of increasing pressure, the diver is repulsed to the centre of the vessel. After the pressure is…

  14. Surface tension and long range corrections of cylindrical interfaces.

    Science.gov (United States)

    Bourasseau, E; Malfreyt, P; Ghoufi, A

    2015-12-21

    The calculation of the surface tension of curved interfaces has been deeply investigated from molecular simulation during this last past decade. Recently, the thermodynamic Test-Area (TA) approach has been extended to the calculation of surface tension of curved interfaces. In the case of the cylindrical vapour-liquid interfaces of water and Lennard-Jones fluids, it was shown that the surface tension was independent of the curvature of the interface. In addition, the surface tension of the cylindrical interface is higher than that of the planar interface. Molecular simulations of cylindrical interfaces have been so far performed (i) by using a shifted potential, (ii) by means of large cutoff without periodic boundary conditions, or (iii) by ignoring the long range corrections to the surface tension due to the difficulty to estimate them. Indeed, unlike the planar interfaces there are no available operational expressions to consider the tail corrections to the surface tension of cylindrical interfaces. We propose here to develop the long range corrections of the surface tension for cylindrical interfaces by using the non-exponential TA (TA2) method. We also extend the formulation of the Mecke-Winkelmann corrections initially developed for planar surfaces to cylindrical interfaces. We complete this study by the calculation of the surface tension of cylindrical surfaces of liquid tin and copper using the embedded atom model potentials.

  15. Surface Tension Screen Failure Detection Method and Apparatus.

    Science.gov (United States)

    Apparatus for detecting failure of a surface tension screen disposed between a holding chamber and a main chamber of a tank includes a fixture for...Comparison of the measurements provides an assessment of the integrity of the surface tension screen. If the measurements are significantly different

  16. Managing tensions during the innovation journey of high tech startups

    NARCIS (Netherlands)

    Groen, A.J.; Wakkee, I.A.M.; de Weerd-Nederhof, P.C.

    2008-01-01

    Answering the question of how enabling technology-based firms manage tensions in their development process, we focus on tensions related to balancing the need to explore new developments for future performance, with the need to exploit existing capabilities to generate sufficient value in the short

  17. Corrosion resistance of grouted post-tensioning systems : [summary].

    Science.gov (United States)

    2013-08-01

    The increased popularity of post-tensioned bridge construction in the United States has led to concerns about corrosion and its impact on the life cycle of these bridges. Although the vast majority of post-tensioned bridges in the United States have ...

  18. Boundary tension of 2D and 3D Ising models

    NARCIS (Netherlands)

    Zandvliet, Henricus J.W.; Hoede, C.

    A simple route to determine the boundary tension of Ising models is proposed. As pointed out by Onsager, the boundary tension is an important quantity since it vanishes at the critical temperature and can thus be used to determine the critical temperature. Here we derive expressions for the boundary

  19. Surface tension of ionic liquids and ionic liquid solutions.

    Science.gov (United States)

    Tariq, Mohammad; Freire, Mara G; Saramago, Benilde; Coutinho, João A P; Lopes, José N Canongia; Rebelo, Luís Paulo N

    2012-01-21

    Some of the most active scientific research fronts of the past decade are centered on ionic liquids. These fluids present characteristic surface behavior and distinctive trends of their surface tension versus temperature. One way to explore and understand their unique nature is to study their surface properties. This critical review analyses most of the surface tension data reported between 2001 and 2010 (187 references).

  20. Recognising Value Tensions That Underlie Problems in Inclusive Education

    Science.gov (United States)

    Norwich, Brahm

    2014-01-01

    This paper aims to examine some tensions that underlie inclusive education as regards pupils with disabilities and difficulties. Two key tensions are analysed: difference as enabling-stigmatising (dilemmas of difference) and participation-protection, both of which can lead to significant dilemmas. Berlin's hedgehog-fox distinction about the unity…