Science.gov

Sample records for affordable electric traction

  1. Electric Transport Traction Power Supply System With Distributed Energy Sources

    NASA Astrophysics Data System (ADS)

    Abramov, E. Y.; Schurov, N. I.; Rozhkova, M. V.

    2016-04-01

    The paper states the problem of traction substation (TSS) leveling of daily-load curve for urban electric transport. The circuit of traction power supply system (TPSS) with distributed autonomous energy source (AES) based on photovoltaic (PV) and energy storage (ES) units is submitted here. The distribution algorithm of power flow for the daily traction load curve leveling is also introduced in this paper. In addition, it illustrates the implemented experiment model of power supply system.

  2. Advanced Electric Traction System Technology Development

    SciTech Connect

    Anderson, Iver

    2011-01-14

    As a subcontractor to General Motors (GM), Ames Laboratory provided the technical expertise and supplied experimental materials needed to assess the technology of high energy bonded permanent magnets that are injection or compression molded for use in the Advanced Electric Traction System motor. This support was a sustained (Phase 1: 6/07 to 3/08) engineering effort that builds on the research achievements of the primary FreedomCAR project at Ames Laboratory on development of high temperature magnet alloy particulate in both flake and spherical powder forms. Ames Lab also provide guidance and direction in selection of magnet materials and supported the fabrication of experimental magnet materials for development of injection molding and magnetization processes by Arnold Magnetics, another project partner. The work with Arnold Magnetics involved a close collaboration on particulate material design and processing to achieve enhanced particulate properties and magnetic performance in the resulting bonded magnets. The overall project direction was provided by GM Program Management and two design reviews were held at GM-ATC in Torrance, CA. Ames Lab utilized current expertise in magnet powder alloy design and processing, along with on-going research advances being achieved under the existing FreedomCAR Program project to help guide and direct work during Phase 1 for the Advanced Electric Traction System Technology Development Program. The technical tasks included review of previous GM and Arnold Magnets work and identification of improvements to the benchmark magnet material, Magnequench MQP-14-12. Other benchmark characteristics of the desired magnet material include 64% volumetric loading with PPS polymer and a recommended maximum use temperature of 200C. A collaborative relationship was maintained with Arnold Magnets on the specification and processing of the bonded magnet material required by GM-ATC.

  3. Electric vehicle regenerative antiskid braking and traction control system

    DOEpatents

    Cikanek, S.R.

    1995-09-12

    An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydraulic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control. 10 figs.

  4. Electric vehicle regenerative antiskid braking and traction control system

    DOEpatents

    Cikanek, Susan R.

    1995-01-01

    An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydrualic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control.

  5. Digital Model of Railway Electric Traction Lines

    NASA Astrophysics Data System (ADS)

    Garg, Rachana; Mahajan, Priya; Kumar, Parmod

    2016-08-01

    The characteristic impedance and propagation constant define the behavior of signal propagation over the transmission lines. The digital model for railway traction lines which includes railway tracks is developed, using curve fitting technique in MATLAB. The sensitivity of this model has been computed with respect to frequency. The digital sensitivity values are compared with the values of analog sensitivity. The developed model is useful for digital protection, integrated operation, control and planning of the system.

  6. Rare-Earth-Free Traction Motor: Rare Earth-Free Traction Motor for Electric Vehicle Applications

    SciTech Connect

    2012-01-01

    REACT Project: Baldor will develop a new type of traction motor with the potential to efficiently power future generations of EVs. Unlike today’s large, bulky EV motors which use expensive, imported rare-earth-based magnets, Baldor’s motor could be light, compact, contain no rare earth materials, and have the potential to deliver more torque at a substantially lower cost. Key innovations in this project include the use of a unique motor design, incorporation of an improved cooling system, and the development of advanced materials manufacturing techniques. These innovations could significantly reduce the cost of an electric motor.

  7. Design study of toroidal traction CVT for electric vehicles

    NASA Technical Reports Server (NTRS)

    Raynard, A. E.; Kraus, J.; Bell, D. D.

    1980-01-01

    The development, evaluation, and optimization of a preliminary design concept for a continuously variable transmission (CVT) to couple the high-speed output shaft of an energy storage flywheel to the drive train of an electric vehicle is discussed. An existing computer simulation program was modified and used to compare the performance of five CVT design configurations. Based on this analysis, a dual-cavity full-toroidal drive with regenerative gearing is selected for the CVT design configuration. Three areas are identified that will require some technological development: the ratio control system, the traction fluid properities, and evaluation of the traction contact performance. Finally, the suitability of the selected CVT design concept for alternate electric and hybrid vehicle applications and alternate vehicle sizes and maximum output torques is determined. In all cases the toroidal traction drive design concept is applicable to the vehicle system. The regenerative gearing could be eliminated in the electric powered vehicle because of the reduced ratio range requirements. In other cases the CVT with regenerative gearing would meet the design requirements after appropriate adjustments in size and reduction gearing ratio.

  8. Electric propulsion -- Fleet readiness at affordable costs

    SciTech Connect

    Orndorff, C.M.; Egan, C.J.

    1996-11-01

    The successful development and demonstration of the Al-AgO primary battery system dramatically demonstrated the viability of electric power plants for torpedo propulsion. Present efforts are focused on the development and demonstration of very low cost, quiet, high performance, safe, environmentally compatible, rechargeable batteries for heavyweight and lightweight torpedoes and tactical-sized UUVs. Electric power plants consisting of a rechargeable battery and a high reliability motor must be affordable to own and operate and enable turn around without teardown for today`s Fleet assets.

  9. Low cost, compact, and high efficiency traction motor for electric and hybrid electric vehicles

    SciTech Connect

    Ehsani, Mark

    2002-10-07

    A new motor drive, the switched reluctance motor drive, has been developed for hybrid-electric vehicles. The motor drive has been designed, built and tested in the test bed at a near vehicle scale. It has been shown that the switched reluctance motor drive is more suitable for traction application than any other motor drive.

  10. Fuzzy logic electric vehicle regenerative antiskid braking and traction control system

    DOEpatents

    Cikanek, S.R.

    1994-10-25

    An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative braking control, hydraulic braking control, and traction control. 123 figs.

  11. Fuzzy logic electric vehicle regenerative antiskid braking and traction control system

    DOEpatents

    Cikanek, Susan R.

    1994-01-01

    An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative braking control, hydraulic braking control, and traction control.

  12. Electric Motor Thermal Management for Electric Traction Drives (Presentation)

    SciTech Connect

    Bennion, K.; Cousineau, J.; Moreno, G.

    2014-09-01

    Thermal constraints place significant limitations on how electric motors ultimately perform. Finite element analysis and computational fluid dynamics modeling approaches are being increasingly utilized in the design and analysis of electric motors. As the models become more sophisticated, it is important to have detailed and accurate knowledge of material thermal properties and convective heat transfer coefficients. In this work, the thermal properties and inter-lamination thermal contact resistances were measured for different stator lamination materials. Also, convective heat transfer coefficients of automatic transmission fluid (ATF) jets were measured to better understand the heat transfer of ATF impinging on motor copper windings. Experiments were carried out at various ATF temperatures and jet velocities to quantify the influence of these parameters on heat transfer coefficients.

  13. An overview of the development of lead/acid traction batteries for electric vehicles in India

    NASA Astrophysics Data System (ADS)

    Sivaramaiah, G.; Subramanian, V. R.

    Electric vehicles (EVs) made an entry into the Indian scene quite recently in the area of passenger transportation, milk floats and other similar applications. The industrial EV market, with various models of fork-lift trucks and platform trucks already in wide use all over India, is a better understood application of EV batteries. The lead/acid traction batteries available in India are not of high-energy density. The best available indigenous lead/acid traction battery has an energy density ( C/5 rate) of 30 W h kg -1 as against 39 W h kg -1 available abroad. This paper reviews the developmental efforts relating to lead/acid traction batteries for electric vehicle applications in India, such as prototype road vehicles, commercial vehicles, rail cars, and locomotives. Due to the need for environmental protection and recognition of exhaustible, finite supplies of petroleum fuel, the Indian government is presently taking active interest in EV projects.

  14. Electric machine differential for vehicle traction control and stability control

    NASA Astrophysics Data System (ADS)

    Kuruppu, Sandun Shivantha

    Evolving requirements in energy efficiency and tightening regulations for reliable electric drivetrains drive the advancement of the hybrid electric (HEV) and full electric vehicle (EV) technology. Different configurations of EV and HEV architectures are evaluated for their performance. The future technology is trending towards utilizing distinctive properties in electric machines to not only to improve efficiency but also to realize advanced road adhesion controls and vehicle stability controls. Electric machine differential (EMD) is such a concept under current investigation for applications in the near future. Reliability of a power train is critical. Therefore, sophisticated fault detection schemes are essential in guaranteeing reliable operation of a complex system such as an EMD. The research presented here emphasize on implementation of a 4kW electric machine differential, a novel single open phase fault diagnostic scheme, an implementation of a real time slip optimization algorithm and an electric machine differential based yaw stability improvement study. The proposed d-q current signature based SPO fault diagnostic algorithm detects the fault within one electrical cycle. The EMD based extremum seeking slip optimization algorithm reduces stopping distance by 30% compared to hydraulic braking based ABS.

  15. Electric vehicle traction motors - The development of an advanced motor concept

    NASA Technical Reports Server (NTRS)

    Campbell, P.

    1980-01-01

    An axial-field permanent magnet traction motor is described, similar to several advanced motors that are being developed in the United States. This type of machine has several advantages over conventional dc motors, particularly in the electric vehicle application. The rapidly changing cost of magnetic materials, particularly cobalt, makes it important to study the utilization of permanent magnet materials in such machines. The impact of different magnets on machine design is evaluated, and the advantages of using iron powder composites in the armature are assessed.

  16. A traction control strategy with an efficiency model in a distributed driving electric vehicle.

    PubMed

    Lin, Cheng; Cheng, Xingqun

    2014-01-01

    Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the two-dimensional design space composed of the acceleration pedal signal and the vehicle speed. The sliding mode control strategy for the joint roads and the efficiency model for the typical drive cycles were simulated. Simulation results show that the proposed driving control approach has the potential to apply to different road surfaces. It keeps the wheels' slip ratios within the stable zone and improves the fuel economy on the premise of tracking the driver's intention. PMID:25197697

  17. A traction control strategy with an efficiency model in a distributed driving electric vehicle.

    PubMed

    Lin, Cheng; Cheng, Xingqun

    2014-01-01

    Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the two-dimensional design space composed of the acceleration pedal signal and the vehicle speed. The sliding mode control strategy for the joint roads and the efficiency model for the typical drive cycles were simulated. Simulation results show that the proposed driving control approach has the potential to apply to different road surfaces. It keeps the wheels' slip ratios within the stable zone and improves the fuel economy on the premise of tracking the driver's intention.

  18. A Traction Control Strategy with an Efficiency Model in a Distributed Driving Electric Vehicle

    PubMed Central

    Lin, Cheng

    2014-01-01

    Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the two-dimensional design space composed of the acceleration pedal signal and the vehicle speed. The sliding mode control strategy for the joint roads and the efficiency model for the typical drive cycles were simulated. Simulation results show that the proposed driving control approach has the potential to apply to different road surfaces. It keeps the wheels' slip ratios within the stable zone and improves the fuel economy on the premise of tracking the driver's intention. PMID:25197697

  19. PM Motor Parametric Design Analyses for a Hybrid Electric Vehicle Traction Drive Application

    SciTech Connect

    Staunton, R.H.

    2004-10-11

    The Department of Energy's (DOE) Office of FreedomCAR (Cooperative Automotive Research) and Vehicle Technologies office has a strong interest in making rapid progress in permanent magnet (PM) machine development. The DOE FreedomCAR program is directing various technology development projects that will advance the technology and hopefully lead to a near-term request for proposals (RFP) for a to-be-determined level of initial production. This aggressive approach is possible because the technology is clearly within reach and the approach is deemed essential, based on strong market demand, escalating fuel prices, and competitive considerations. In response, this study began parallel development paths that included a literature search/review, development and utilization of multiple parametric models, verification of the modeling methodology, development of an interior PM (IPM) machine baseline design, development of alternative machine baseline designs, and cost analyses for several candidate machines. This report summarizes the results of these activities as of September 2004. This report provides background and summary information for recent machine parametric studies and testing programs that demonstrate both the potential capabilities and technical limitations of brushless PM machines (axial gap and radial gap), the IPM machine, the surface-mount PM machines (interior or exterior rotor), induction machines, and switched-reluctance machines. The FreedomCAR program, while acknowledging the progress made by Oak Ridge National Laboratory (ORNL), Delphi, Delco-Remy International, and others in these programs, has redirected efforts toward a ''short path'' to a marketable and competitive PM motor for hybrid electric vehicle (HEV) traction applications. The program has developed a set of performance targets for the type of traction machine desired. The short-path approach entails a comprehensive design effort focusing on the IPM machine and meeting the performance targets

  20. PM Motor Parametric Design Analyses for Hybrid Electric Vehicle Traction Drive Application: Interim Report

    SciTech Connect

    Staunton, R.H.

    2004-08-11

    The Department of Energy's (DOE) Office of FreedomCAR (Cooperative Automotive Research) and Vehicle Technologies has a strong interest in making rapid progress in permanent magnet (PM) machine development. The program is directing various technology development projects that will advance the technology and lead to request for proposals (RFP) for manufacturer prototypes. This aggressive approach is possible because the technology is clearly within reach and the approach is deemed essential, based on strong market demand, escalating fuel prices, and competitive considerations. In response, this study began parallel development paths that included a literature search/review, development and utilization of multiple parametric models to determine the effects of design parameters, verification of the modeling methodology, development of an interior PM (IPM) machine baseline design, development of alternative machine baseline designs, and cost analyses for several candidate machines. This interim progress report summarizes the results of these activities as of June 2004. This report provides background and summary information for recent machine parametric studies and testing programs that demonstrate both the potential capabilities and technical limitations of brushless PM machines (axial gap and radial gap), the IPM machine, the surface-mount PM machines (interior or exterior rotor), induction machines, and switched reluctance machines. The FreedomCAR program, while acknowledging the progress made by Oak Ridge National Laboratory, Delphi, Delco-Remy International, and others in these programs, has redirected efforts toward a ''short path'' to a marketable and competitive PM motor for hybrid electric vehicle traction applications. The program has developed a set of performance targets for the type of traction machine desired. The short-path approach entails a comprehensive design effort focusing on the IPM machine and meeting the performance targets. The selection of the

  1. The influence of battery degradation level on the selected traction parameters of a light-duty electric vehicle

    NASA Astrophysics Data System (ADS)

    Juda, Z.; Noga, M.

    2016-09-01

    The article describes results of an analysis of the impact of degradation level of battery made in lead-acid technology on selected traction parameters of an electric light duty vehicle. Lead-acid batteries are still used in these types of vehicles. They do not require complex systems of performance management and monitoring and are easy to maintaining. Despite the basic disadvantage, which is the low value of energy density, low price is a decisive factor for their use in low-speed electric vehicles. The process of aging of the battery related with an increase in internal resistance of the cells and the loss of electric capacity of the battery was considered. A simplified model of cooperation of the DC electric motor with the battery assuming increased internal resistance was presented. In the paper the results of comparative traction research of the light-duty vehicle equipped with a set of new batteries and set of batteries having a significant degradation level were showed. The analysis of obtained results showed that the correct exploitation of the battery can slow down the processes of degradation and, thus, extend battery life cycle.

  2. Design study of a continuously variable roller cone traction CVT for electric vehicles

    NASA Technical Reports Server (NTRS)

    Mccoin, D. K.; Walker, R. D.

    1980-01-01

    Continuously variable ratio transmissions (CVT) featuring cone and roller traction elements and computerized controls are studied. The CVT meets or exceeds all requirements set forth in the design criteria. Further, a scalability analysis indicates the basic concept is applicable to lower and higher power units, with upward scaling for increased power being more readily accomplished.

  3. An Inverter Packaging Scheme for an Integrated Segmented Traction Drive System

    SciTech Connect

    Su, Gui-Jia; Tang, Lixin; Ayers, Curtis William; Wiles, Randy H

    2013-01-01

    The standard voltage source inverter (VSI), widely used in electric vehicle/hybrid electric vehicle (EV/HEV) traction drives, requires a bulky dc bus capacitor to absorb the large switching ripple currents and prevent them from shortening the battery s life. The dc bus capacitor presents a significant barrier to meeting inverter cost, volume, and weight requirements for mass production of affordable EVs/HEVs. The large ripple currents become even more problematic for the film capacitors (the capacitor technology of choice for EVs/HEVs) in high temperature environments as their ripple current handling capability decreases rapidly with rising temperatures. It is shown in previous work that segmenting the VSI based traction drive system can significantly decrease the ripple currents and thus the size of the dc bus capacitor. This paper presents an integrated packaging scheme to reduce the system cost of a segmented traction drive.

  4. A Soft-Switching Inverter for High-Temperature Advanced Hybrid Electric Vehicle Traction Motor Drives

    SciTech Connect

    Lai, Jason; Yu, Wensong; Sun, Pengwei; Leslie, Scott; Prusia, Duane; Arnet, Beat; Smith, Chris; Cogan, Art

    2012-03-31

    The state-of-the-art hybrid electric vehicles (HEVs) require the inverter cooling system to have a separate loop to avoid power semiconductor junction over temperatures because the engine coolant temperature of 105°C does not allow for much temperature rise in silicon devices. The proposed work is to develop an advanced soft-switching inverter that will eliminate the device switching loss and cut down the power loss so that the inverter can operate at high-temperature conditions while operating at high switching frequencies with small current ripple in low inductance based permanent magnet motors. The proposed tasks also include high-temperature packaging and thermal modeling and simulation to ensure the packaged module can operate at the desired temperature. The developed module will be integrated with the motor and vehicle controller for dynamometer and in-vehicle testing to prove its superiority. This report will describe the detailed technical design of the soft-switching inverters and their test results. The experiments were conducted both in module level for the module conduction and switching characteristics and in inverter level for its efficiency under inductive and dynamometer load conditions. The performance will be compared with the DOE original specification.

  5. Subcontract Report: Final Report on Assessment of Motor Technologies for Traction Drives of Hybrid and Electric Vehicles (Subcontract #4000080341)

    SciTech Connect

    Fezzler, Raymond

    2011-03-01

    Currently, interior permanent magnet (IPM) motors with rare-earth (RE) magnets are almost universally used for hybrid and electric vehicles (EVs) because of their superior properties, particularly power density. However, there is now a distinct possibility of limited supply or very high cost of RE magnets that could make IPM motors unavailable or too expensive. Because development of electric motors is a critical part of the U.S. Department of Energy (DOE) Advanced Power Electronics and Motors activity, DOE needs to determine which options should be investigated and what barriers should be addressed. Therefore, in order to provide a basis for deciding which research topics should be pursued, an assessment of various motor technologies was conducted to determine which, if any, is potentially capable of meeting FreedomCAR 2015 and 2020 targets. Highest priority was given to IPM, surface mounted permanent magnet (SPM), induction, and switched reluctance (SR) motors. Also of interest, but with lesser emphasis, were wheel motors, multiple-rotor motors, motors with external excitation, and several others that emerged from the assessment. Cost and power density (from a design perspective, the power density criterion translates to torque density) are emerging as the two most important properties of motors for traction drives in hybrid and EVs, although efficiency and specific power also are very important. The primary approach for this assessment involved interviews with original equipment manufacturers (OEMs), their suppliers, and other technical experts. For each technology, the following issues were discussed: (1) The current state-of-the-art performance and cost; (2) Recent trends in the technology; (3) Inherent characteristics of the motor - which ones limit the ability of the technology to meet the targets and which ones aid in meeting the target; (4) What research and development (R&D) would be needed to meet the targets; and (5) The potential for the technology to

  6. Advanced Integrated Traction System

    SciTech Connect

    Greg Smith; Charles Gough

    2011-08-31

    The United States Department of Energy elaborates the compelling need for a commercialized competitively priced electric traction drive system to proliferate the acceptance of HEVs, PHEVs, and FCVs in the market. The desired end result is a technically and commercially verified integrated ETS (Electric Traction System) product design that can be manufactured and distributed through a broad network of competitive suppliers to all auto manufacturers. The objectives of this FCVT program are to develop advanced technologies for an integrated ETS capable of 55kW peak power for 18 seconds and 30kW of continuous power. Additionally, to accommodate a variety of automotive platforms the ETS design should be scalable to 120kW peak power for 18 seconds and 65kW of continuous power. The ETS (exclusive of the DC/DC Converter) is to cost no more than $660 (55kW at $12/kW) to produce in quantities of 100,000 units per year, should have a total weight less than 46kg, and have a volume less than 16 liters. The cost target for the optional Bi-Directional DC/DC Converter is $375. The goal is to achieve these targets with the use of engine coolant at a nominal temperature of 105C. The system efficiency should exceed 90% at 20% of rated torque over 10% to 100% of maximum speed. The nominal operating system voltage is to be 325V, with consideration for higher voltages. This project investigated a wide range of technologies, including ETS topologies, components, and interconnects. Each technology and its validity for automotive use were verified and then these technologies were integrated into a high temperature ETS design that would support a wide variety of applications (fuel cell, hybrids, electrics, and plug-ins). This ETS met all the DOE 2010 objectives of cost, weight, volume and efficiency, and the specific power and power density 2015 objectives. Additionally a bi-directional converter was developed that provides charging and electric power take-off which is the first step

  7. Elements affecting runway traction

    NASA Technical Reports Server (NTRS)

    Horne, W. B.

    1974-01-01

    The five basic elements affecting runway traction for jet transport aircraft operation are identified and described in terms of pilot, aircraft system, atmospheric, tire, and pavement performance factors or parameters. Where possible, research results are summarized, and means for restoring or improving runway traction for these different conditions are discussed.

  8. Principles of traction.

    PubMed

    Osmond, T

    1999-02-01

    Traction has been the mainstay of orthopaedic management for thousands of years, with its use recorded by the Aztecs and ancient Egyptians. In more recent times, however, the advances in surgical reductions of fractures and muscutoskeletal disruptions, coupled with the economic imperatives of reducing hospital bed stay days has seen a reduction the use of prolonged periods of traction. PMID:10205405

  9. Design of traction drives

    NASA Technical Reports Server (NTRS)

    Loewenthal, S. H.; Zaretsky, E. V.

    1985-01-01

    Traction drives are among the simplest of all speed-changing mechanisms. Because of their simplicity and their ability to smoothly and continuously adjust speed, they are excellent choices for many drive system applications. They have been used in industrial service for more than 100 years. Today's traction drives have power capacities which rival the best gear and belt drives due to modern traction fluids and highly fatigue-resistant bearing steels. This report summarizes methods to analyze and size traction drives. Lubrication principles, contact kinematics, stress, fatigue life, and performance prediction methods are presented. The effects of the lubricant's traction characteristics on life and power loss are discussed. An example problem is given which illustrates the effects of spin on power loss. Loading mechanism design and the design of nonlubricated friction wheels and rings are also treated.

  10. [Electric traction magnetic fields of ultra-low frequency as an occupational risk factor of ischemic heart disease].

    PubMed

    Ptitsyna, N G; Kudrin, V A; Villorezi, D; Kopytenko, Iu A; Tiasto, M I; Kopytenko, E A; Bochko, V A; Iuchchi, N

    1996-01-01

    The study was inspired by earlier results that displayed influence of variable natural geomagnetic field (0.005-10 Hz range-ultra-low frequencies) on circulatory system, indicated possible correlation between industrial ultra-low frequency fields and prevalence of myocardial infarction. The authors conducted unique measurements of ultra-low frequency fields produced by electric engines. The results were compared with data on morbidity among railway transport workers. The findings are that level of magnetic variations in electric locomotive cabin can exceed 280 micro Tesla, whereas that in car sections reaches 50 micro Tesla. Occurrence of coronary heart disease among the locomotive operators appeared to be 2.0 + 0.2 times higher than that among the car section operators. Higher risk of coronary heart disease in the locomotive operators is associated with their increased occupational magnetic load.

  11. Assisting drinking with an affordable BCI-controlled wearable robot and electrical stimulation: a preliminary investigation

    PubMed Central

    2014-01-01

    Background The aim of the present study is to demonstrate, through tests with healthy volunteers, the feasibility of potentially assisting individuals with neurological disorders via a portable assistive technology for the upper extremities (UE). For this purpose the task of independently drinking a glass of water was selected, as it is one of the most basic and vital activities of the daily living that is unfortunately not achievable by individuals severely affected by stroke. Methods To accomplish the aim of this study we introduce a wearable and portable system consisting of a novel lightweight Robotic Arm Orthosis (RAO), a Functional Electrical Stimulation (FES) system, and a simple wireless Brain-Computer Interface (BCI). This system is able to process electroencephalographic (EEG) signals and translate them into motions of the impaired arm. Five healthy volunteers participated in this study and were asked to simulate stroke patient symptoms with no voluntary control of their hand and arm. The setup was designed such as the volitional movements of the healthy volunteers’ UE did not interfere with the evaluation of the proposed assistive system. The drinking task was split into eleven phases of which seven were executed by detecting EEG-based signals through the BCI. The user was asked to imagine UE motion related to the specific phase of the task to be assisted. Once detected by the BCI the phase was initiated. Each phase was then terminated when the BCI detected the volunteers clenching their teeth. Results The drinking task was completed by all five participants with an average time of 127 seconds with a standard deviation of 23 seconds. The incremental motions of elbow extension and elbow flexion were the primary limiting factors for completing this task faster. The BCI control along with the volitional motions also depended upon the users pace, hence the noticeable deviation from the average time. Conclusion Through tests conducted with healthy

  12. Regression analysis of traction characteristics of traction fluids

    NASA Technical Reports Server (NTRS)

    Loewenthal, S. H.; Rohn, D. A.

    1983-01-01

    Traction data for Santotrac 50 and TDF-88 over a wide range of operating conditions were analyzed. An eight term correlation equation to predict the maximum traction coefficient and a six term correlation equation to predict the initial slope of the traction curve were developed. The slope correlation was corrected for size effect considering the compliance of the disks. The effects of different operating conditions on the traction performance of each traction fluid were studied. Both fluids exhibited a loss in traction with increases in spin, but the losses with the TDF-88 fluid were not as severe as those with Santotrac 50. Overall, both fluids exhibited similar performance, showing an increase in traction with contact pressure up to about 2.0 GPa, and a reduction in traction with higher surface speeds up to about 100 m/sec. The apparent stiffness of the traction contact, that is, film disk combination, increases with contact pressure and decreases with speed.

  13. An advanced pitch change mechanism incorporating a hybrid traction drive

    NASA Technical Reports Server (NTRS)

    Steinetz, B. M.; Loewenthal, S. H.; Sargisson, D. F.; White, G.

    1984-01-01

    A design of a propeller pitch control mechanism is described that meets the demanding requirements of a high-power, advanced turboprop. In this application, blade twisting moment torque can be comparable to that of the main reduction gearbox output: precise pitch control, reliability and compactness are all at a premium. A key element in the design is a compact, high-ratio hybrid traction drive which offers low torque ripple and high torsional stiffness. The traction drive couples a high speed electric motor/alternator unit to a ball screw that actuates the blade control links. The technical merits of this arrangement and the performance characteristics of the traction drive are discussed.

  14. Starting Phenomena and Temperature-rise under vvvf Supply of Three-Phase Squirrel-Cage ac Traction Motor of Electric Locomotive

    NASA Astrophysics Data System (ADS)

    Paul, R. N.; Arya, L. D.; Verma, H. K.

    2012-09-01

    In three-phase squirrel-cage ac traction motor, temperature-rise calculation during variable-voltage and variable-frequency starting is of vital importance and has to be predicted and critically examined. Under voltage source inverter supply with PWM, the generation of harmonics by inverter supply reduces the output during starting due to higher harmonic losses, thereby reducing the starting tractive effort in kN on locomotive wheel. Stator and rotor temperature-rises during starting have been determined for average acceleration torque in segmental zone (calculated from variable acceleration) which have been presented in the paper with both copper and aluminium alloy rotor bars.

  15. Patchy Traction Alopecia Mimicking Areata

    PubMed Central

    Barbosa, Aline Blanco; Donati, Aline; Valente, Neusa S; Romiti, Ricardo

    2015-01-01

    Acute traction alopecia is a diagnostic challenge when the external factor is not suspected or admitted. We report two female patients with non-scarring patchy alopecia resulting from traction of video-electroencephalogram electrodes in which the clinical diagnosis of alopecia areata was suspected. Associated diffuse hair disorders might be implicated in these cases. The correct diagnosis of traction alopecia is important in order to avoid unnecessary treatments. PMID:26903751

  16. Advances in traction drive technology

    NASA Technical Reports Server (NTRS)

    Loewenthal, S. H.; Anderson, N. E.; Rohn, D. A.

    1983-01-01

    Traction drives are traced from early uses as main transmissions in automobiles at the turn of the century to modern, high-powered traction drives capable of transmitting hundreds of horsepower. Recent advances in technology are described which enable today's traction drive to be a serious candidate for off-highway vehicles and helicopter applications. Improvements in materials, traction fluids, design techniques, power loss and life prediction methods will be highlighted. Performance characteristics of the Nasvytis fixed-ratio drive are given. Promising future drive applications, such as helicopter main transmissions and servo-control positioning mechanisms are also addressed.

  17. Halo traction device.

    PubMed

    Manthey, D E

    1994-08-01

    A thorough understanding of the underlying diseases and of the halo pin traction device will allow for appropriate treatment of complications. Consultation or referral to the neurosurgeon is advised to prevent serious sequelae. The following points should be remembered: 1. Pins should only be tightened during the first 24-hour period after application. 2. Pin infection is treated by local wound care in most cases. 3. CT scan cannot completely exclude the presence of an abscess secondary to artifact, but MRI may be compatible with the newer devices. 4. Pin penetration of the inner table of the skull requires admission. 5. Any suspected loss of alignment or reduction of the cervical spine requires C-spine immobilization. 5. Nasotracheal or fiberoptic intubation or emergent cricothyroidotomy should be used if orotracheal intubation proves difficult due to the device. 7. The anterior portion of the vest is removable for cardiopulmonary resuscitation without compromising the stability of the device. PMID:8062799

  18. Simple cost model for EV traction motors

    SciTech Connect

    Cuenca, R.M.

    1995-02-01

    A simple cost model has been developed that allows the calculation of the OEM cost of electric traction motors of three different types, normalized as a function of power in order to accommodate different power and size. The model includes enough information on the various elements integrated in the motors to allow analysis of individual components and to factor-in the effects of changes in commodities prices. A scalable cost model for each of the main components of an electric vehicle (EV) is a useful tool that can have direct application in computer simulation or in parametric studies. For the cost model to have wide usefulness, it needs to be valid for a range of values of some parameter that determines the magnitude or size of the component. For instance, in the case of batteries, size may be determined by energy capacity, usually expressed in kilowatt-hours (kWh), while in the case of traction motors, size is better determined by rated power, usually expressed in kilowatts (kW). The simplest case is when the cost of the component in question is a direct function of its size; then cost is simply the product of its specific cost ($/unit size) and the number of units (size) in the vehicle in question. Batteries usually fall in this category (cost = energy capacity x $/kWh). But cost is not always linear with size or magnitude; motors (and controllers), for instance, become relatively less expensive as power rating increases. Traction motors, one of the main components for EV powertrains are examined in this paper, and a simplified cost model is developed for the three most popular design variations.

  19. An advanced pitch change mechanism incorporating a hybrid traction drive

    NASA Technical Reports Server (NTRS)

    Steinetz, B. M.; Sargisson, D. F.; White, G.; Loewenthal, S. H.

    1984-01-01

    A design of a propeller pitch control mechanism is described that meets the demanding requirements of a high-power, advanced turboprop. In this application, blade twisting moment torque can be comparable to that of the main reduction gearbox output: precise pitch control, reliability and compactness are all at a premium. A key element in the design is a compact, high-ratio hybrid traction drive which offers low torque ripple and high torsional stiffness. The traction drive couples a high speed electric motor/alternator unit to a ball screw that actuates the blade control links. The technical merits of this arrangement and the performance characteristics of the traction drive are discussed. Comparisons are made to the more conventional pitch control mechanisms.

  20. Electricity Security and Affordability Act

    THOMAS, 113th Congress

    Rep. Whitfield, Ed [R-KY-1

    2014-01-09

    05/08/2014 Read the second time. Placed on Senate Legislative Calendar under General Orders. Calendar No. 374. (All Actions) Tracker: This bill has the status Passed HouseHere are the steps for Status of Legislation:

  1. Traction of Pneumatic Tires on Wet Runways

    NASA Technical Reports Server (NTRS)

    Horne, Walter B.; Joyner, Upshur T.

    1965-01-01

    Recent work on the traction of pneumatic tires on wet runways is discussed, and it is shown that a loss of tire traction adversely affects cross-wind landings. The effect of runway surface texture is discussed,, and a simple method for measuring surface texture is described. A preliminary correlation of tire traction with surface texture is shown. Results of work at Langley Research Center on the use of air jets to improve tire traction on wet or flooded runways indicate that this is a promising approach for alleviating the large losses in tire braking and sideways traction that occur when tire hydroplaning occurs on a flooded runway.

  2. Traction contact performance evaluation at high speeds

    NASA Technical Reports Server (NTRS)

    Tevaarwerk, J. L.

    1981-01-01

    The results of traction tests performed on two fluids are presented. These tests covered a pressure range of 1.0 to 2.5 GPa, an inlet temperature range of 30 'C to 70 'C, a speed range of 10 to 80 m/sec, aspect ratios of .5 to 5 and spin from 0 to 2.1 percent. The test results are presented in the form of two dimensionless parameters, the initial traction slope and the maximum traction peak. With the use of a suitable rheological fluid model the actual traction curves measured can now be reconstituted from the two fluid parameters. More importantly, the knowledge of these parameters together with the fluid rheological model, allow the prediction of traction under conditions of spin, slip and any combination thereof. Comparison between theoretically predicted traction under these conditions and those measured in actual traction tests shows that this method gives good results.

  3. Application of traction drives as servo mechanisms

    NASA Technical Reports Server (NTRS)

    Loewenthal, S. H.; Rohn, D. A.; Steinetz, B. M.

    1985-01-01

    The suitability of traction drives for a wide class of aerospace control mechanisms is examined. Potential applications include antenna or solar array drive positioners, robotic joints, control moment gyro (CMG) actuators and propeller pitch change mechanisms. In these and similar applications the zero backlash, high torsional stiffness, low hysteresis and torque ripple characteristics of traction drives are of particular interest, as is the ability to run without liquid lubrication in certain cases. Wear and fatigue considerations for wet and dry operation are examined along with the tribological performance of several promising self lubricating polymers for traction contracts. The speed regulation capabilities of variable ratio traction drives are reviewed. A torsional stiffness analysis described suggests that traction contacts are relatively stiff compared to gears and are significantly stiffer than the other structural elements in the prototype CMG traction drive analyzed. Discussion is also given of an advanced turboprop propeller pitch change mechanism that incorporates a traction drive.

  4. Elastohydrodynamic Traction Properties of Seed Oils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The elastohydrodynamic traction coefficient (tc) properties of nine seed oils of varying chemical structures, PAO and hexadecane, were investigated using a ball-on disk traction apparatus. The seed oils were: castor oil, a triglyceride with hydroxyl functional group; jojoba, a monoglyceride; and s...

  5. Elastohydrodynamic (EHD) traction properties of seed oils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The elastohydrodynamic traction coefficient (tc) properties of nine seed oils of varying chemical structures, PAO and hexadecane, were investigated using a ball-on disk traction apparatus. The seed oils were: castor oil, a triglyceride with hydroxyl functional group; jojoba, a monoglyceride; and sev...

  6. 21 CFR 890.5925 - Traction accessory.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Traction accessory. 890.5925 Section 890.5925 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory....

  7. 21 CFR 890.5925 - Traction accessory.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Traction accessory. 890.5925 Section 890.5925 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory....

  8. 21 CFR 890.5925 - Traction accessory.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Traction accessory. 890.5925 Section 890.5925 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory....

  9. 21 CFR 890.5925 - Traction accessory.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Traction accessory. 890.5925 Section 890.5925 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory....

  10. 21 CFR 890.5925 - Traction accessory.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Traction accessory. 890.5925 Section 890.5925 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory....

  11. Advanced dc-Traction-Motor Control System

    NASA Technical Reports Server (NTRS)

    Vittone, O.

    1985-01-01

    Motor-control concept for battery-powered vehicles includes stateof-the-art power-transistor switching and separate excitation of motor windings in traction and regenerative braking. Switching transistors and other components of power-conditioning subsystem operate under control of computer that coordinates traction, braking, and protective functions.

  12. Traction

    MedlinePlus

    Browner BD, Jupiter JB, Krettek C, Anderson PA. Craniocervical injuries. In: Browner BD, Jupiter JB, Krettek C, Anderson PA, eds. Skeletal Trauma: Basic Science, Management, and Reconstruction . 5th ed. ...

  13. Simplified and advanced modelling of traction control systems of heavy-haul locomotives

    NASA Astrophysics Data System (ADS)

    Spiryagin, Maksym; Wolfs, Peter; Szanto, Frank; Cole, Colin

    2015-05-01

    Improving tractive effort is a very complex task in locomotive design. It requires the development of not only mechanical systems but also power systems, traction machines and traction algorithms. At the initial design stage, traction algorithms can be verified by means of a simulation approach. A simple single wheelset simulation approach is not sufficient because all locomotive dynamics are not fully taken into consideration. Given that many traction control strategies exist, the best solution is to use more advanced approaches for such studies. This paper describes the modelling of a locomotive with a bogie traction control strategy based on a co-simulation approach in order to deliver more accurate results. The simplified and advanced modelling approaches of a locomotive electric power system are compared in this paper in order to answer a fundamental question. What level of modelling complexity is necessary for the investigation of the dynamic behaviours of a heavy-haul locomotive running under traction? The simulation results obtained provide some recommendations on simulation processes and the further implementation of advanced and simplified modelling approaches.

  14. Traction drive performance prediction for the Johnson and Tevaarwerk traction model

    NASA Technical Reports Server (NTRS)

    Tevaarwerk, J. L.

    1979-01-01

    The fluid rheology model is used to investigate the traction behavior for typical traction drive contacts. The aspect ratio of the contact and the invariably present spin are investigated. Contacts with a low aspect ratio predict a superior performance in that they show less slip for the same degree of traction. Spin always has a diminishing effect on the traction at the same slip. At sufficiently high spin the model may be simplified to a limiting shear stress model. The conventional rigid plastic analysis applies here equally well.

  15. [Traction maculopathies--pathogenesis and diagnostics].

    PubMed

    Wylegała, Edward; Woyna-Orlewicz, Anna; Piłat, Jarosław; Teper, Sławomir; Ludyga, Aneta

    2006-01-01

    Traction maculopathies are a group of age-related degenerative diseases characterized by pathology of vitreomacular interface including idiopathic epimacular membranes, vitreomacular traction syndrome and idiopathic macular hole. The disorders develop due to mechanical forces caused by focal condensation or incomplete detachement of vitreous and shrinkage of pathological membranes. The forces can be tangential to retinal surface in epiretinal membranes, anterior-posterior in vitreomacular traction syndrome and oblique (trampoline) in idiopathic macular hole. Authors discuss pathogenesis and diagnostics of traction maculopathies with use of optical coherence tomography and microperimetry, based on current literature. This work presents also idiopathic macular hole classification with use of optical coherence tomography images compared with biomicroscopic classification by Gass.

  16. Home cervical traction: evaluation of alternate equipment.

    PubMed

    Waylonis, G W; Tootle, D; Denhart, C; Pope Grattan, M M; Wapenski, J A

    1982-08-01

    Overhead intermittent cervical traction is often utilized to control the symptoms of cervical radiculopathy associated with osteoarthritis. The long-term home use of presently available counterweight systems has often presented problems including: (1) lack of patient compliance, (2) difficulty with application by elderly or debilitated patients, (3) tensing of both the cervical paraspinalis and upper extremity muscles while maneuvering the counterweights, and (4) discomfort while using the device. A prototype home pneumatic traction device was developed, which has many of the advantages of the expensive hydraulic units in common use in physical therapy departments. The initial favorable responses of 17 patients led to the development of a prototype commercial unit in cooperation with the Jobst Company. Of 36 patients who used the pneumatic traction device at home, 29 (81%) preferred it to the conventional counterweight system. Typical reasons were that it was easier to use, more "workable" and provided a steadier pull with more gradual onset of traction. Disadvantages most commonly mentioned were minor air pressure loss in the hand pump model and the complexity of the unit. The most rational approach to the use of these new pneumatic devices would be to initiate a home traction program using conventional counterweight units and then to switch to the pneumatic unit for long-term patients or those who are unable to apply conventional traction systems unassisted.

  17. Affordable Care Act.

    PubMed

    Rak, Sofija; Coffin, Janis

    2013-01-01

    The Patient Protection and Affordable Care Act of 2010 (PPACA), although a subject of much debate in the Unites States, was enacted on March 23, 2010, and upheld by the Supreme Court on June 28, 2012. This act advocates that "healthcare is a right, not a privilege." The main goals of PPACA are to minimize the number of uninsured Americans and make healthcare available to everyone at an affordable price. The Congressional Budget Office has determined that 94% of Americans will have healthcare coverage while staying under the $900 billion limit that President Barack Obama established by bending the healthcare cost curve and reducing the deficit over the next 10 years. PMID:23767130

  18. Affordable Vehicle Avionics Overview

    NASA Technical Reports Server (NTRS)

    Cockrell, James J.

    2015-01-01

    Public and private launch vehicle developers are reducing the cost of propulsion for small commercial launchers, but conventional high-performance, high-reliability avionics remain the disproportionately high cost driver for launch. AVA technology performs as well or better than conventional launch vehicle avionics, but with a fraction of the recurring costs. AVA enables small launch providers to offer affordable rides to LEO to nano-satellites as primary payloads meaning, small payloads can afford to specify their own launch and orbit parameters

  19. Affordable Vehicle Avionics Overview

    NASA Technical Reports Server (NTRS)

    Cockrell, James J.

    2015-01-01

    Public and private launch vehicle developers are reducing the cost of propulsion for small commercial launchers, but conventional high-performance, high-reliability avionics remain the disproportionately high cost driver for launch. AVA technology performs as well or better than conventional launch vehicle avionics, but with a fraction of the recurring costs. AVA enables small launch providers to offer affordable rides to LEO to nano-satellites as primary payloads meaning, small payloads can afford to specify their own launch and orbit parameters.

  20. Changes in joint space width during Kaltenborn traction according to traction grade in healthy adults.

    PubMed

    Moon, Gui-do; Kim, Tae-Ho; Lim, Jin-Yong

    2016-01-01

    [Purpose] The aim of this study was to analyze the joint space width of the humeral head and glenoid fossa during traction under 2 grade conditions (grade 2/grade 3). [Subjects and Methods] The subjects were 20 healthy male adults who had not experienced any shoulder injury. Three radiographs were obtained with the subjects in the supine position (resting, grades 2 and 3). The glenohumeral joint space was examined on radiography. Joint space width was measured by a radiologist at the points described by Petersson and Redlund-Johnell. A radiologist blinded to the variable "resting" or "traction" performed all radiographic measurements. The joint space widths were compared by using one-way repeated-measures analysis of variance. [Results] The results of this study indicated significant differences in the changes in joint space width according to traction grade. Compared to resting, grades 2 and 3 traction significantly increased joint space width. However, no significant difference in joint space width was found between grades 2 and 3 traction. [Conclusion] Although no significant differences were found between grades 2 and 3 traction during glenohumeral joint traction, the increase in joint space width between the glenoid fossa and humeral head was highest during grade 3 traction.

  1. Rolling, slip and traction measurements on low modulus materials

    NASA Technical Reports Server (NTRS)

    Tevaarwerk, J. L.

    1985-01-01

    Traction and wear tests were performed on six low modulus materials (LMM). Three different traction tests were performed to determine the suitability of the material for use as traction rollers. These were the rolling, slip and endurance traction tests. For each material the combination LMM on LMM and LMM on steel were evaluated. Rolling traction test were conducted to determine the load - velocity limits, the rolling traction coefficient of the materials and to establish the type of failures that would result when loading beyond the limit. It was found that in general a simple constant rolling traction coefficient was enough to describe the results of all the test. The slip traction tests revealed that the peak traction coefficients were considerably higher than for lubricated traction contacts. The endurance traction tests were performed to establish the durability of the LMM under conditions of prolonged traction. Wear measurements were performed during and after the test. Energetic wear rates were determined from the wear measurements conducted in the endurance traction tests. These values show that the roller wear is not severe when reasonable levels of traction are transmitted.

  2. Characterising the interaction of individual-wheel drives with traction by linear parameter-varying model: a method for analysing the role of traction in torsional vibrations in wheel drives and active damping

    NASA Astrophysics Data System (ADS)

    Zhun Yeap, Khang; Müller, Steffen

    2016-02-01

    A model-based approach for characterising the interaction of individual-wheel drives with traction is contributed in this article. The primary aim is to investigate the influence of traction on torsional vibration behaviour in the drive train. The essence of this approach lies in reformulating the nonlinear traction behaviour into its differential form, which enables an analytical description of this interaction in its linear parameter-varying model equivalence. Analytical statements on the vibration behaviour for different driving scenarios are inferred from this model and validated with measurement samples from a high-performance electric road vehicle. Subsequent influences of traction on the performance of active damping of torsional vibrations are derived from this model.

  3. Advanced endoscopic submucosal dissection with traction

    PubMed Central

    Imaeda, Hiroyuki; Hosoe, Naoki; Kashiwagi, Kazuhiro; Ohmori, Tai; Yahagi, Naohisa; Kanai, Takanori; Ogata, Haruhiko

    2014-01-01

    Endoscopic submucosal dissection (ESD) has been established as a standard treatment for early stage gastric cancer (EGC) in Japan and has spread worldwide. ESD has been used not only for EGC but also for early esophageal and colonic cancers. However, ESD is associated with several adverse events, such as bleeding and perforation, which requires more skill. Adequate tissue tension and clear visibility of the tissue to be dissected are important for effective and safe dissection. Many ESD methods using traction have been developed, such as clip-with-line method, percutaneous traction method, sinker-assisted method, magnetic anchor method, external forceps method, internal-traction method, double-channel-scope method, outerroute method, double-scope method, endoscopic-surgical-platform, and robot-assisted method. Each method has both advantages and disadvantages. Robotic endoscopy, enabling ESD with a traction method, will become more common due to advances in technology. In the near future, simple, noninvasive, and effective ESD using traction is expected to be developed and become established as a worldwide standard treatment for superficial gastrointestinal neoplasias. PMID:25031787

  4. Confocal reference free traction force microscopy

    PubMed Central

    Bergert, Martin; Lendenmann, Tobias; Zündel, Manuel; Ehret, Alexander E.; Panozzo, Daniele; Richner, Patrizia; Kim, David K.; Kress, Stephan J. P.; Norris, David J.; Sorkine-Hornung, Olga; Mazza, Edoardo; Poulikakos, Dimos; Ferrari, Aldo

    2016-01-01

    The mechanical wiring between cells and their surroundings is fundamental to the regulation of complex biological processes during tissue development, repair or pathology. Traction force microscopy (TFM) enables determination of the actuating forces. Despite progress, important limitations with intrusion effects in low resolution 2D pillar-based methods or disruptive intermediate steps of cell removal and substrate relaxation in high-resolution continuum TFM methods need to be overcome. Here we introduce a novel method allowing a one-shot (live) acquisition of continuous in- and out-of-plane traction fields with high sensitivity. The method is based on electrohydrodynamic nanodrip-printing of quantum dots into confocal monocrystalline arrays, rendering individually identifiable point light sources on compliant substrates. We demonstrate the undisrupted reference-free acquisition and quantification of high-resolution continuous force fields, and the simultaneous capability of this method to correlatively overlap traction forces with spatial localization of proteins revealed using immunofluorescence methods. PMID:27681958

  5. Recent traction methods for endoscopic submucosal dissection

    PubMed Central

    Tsuji, Kunihiro; Yoshida, Naohiro; Nakanishi, Hiroyoshi; Takemura, Kenichi; Yamada, Shinya; Doyama, Hisashi

    2016-01-01

    Endoscopic mucosal resection (EMR) is problematic with regard to en bloc and curable resection rates. Advancements in endoscopic techniques have enabled novel endoscopic approaches such as endoscopic submucosal dissection (ESD), which has overcome some EMR problems, and has become the standard treatment for gastrointestinal tumors. However, ESD is technically difficult. Procedure time is longer and complications such as intraoperative perforation and bleeding occur more frequently than in EMR. Recently various traction methods have been introduced to facilitate ESD procedures, such as clip with line, external forceps, clip and snare, internal traction, double scope, and magnetic anchor. Each method must be used appropriately according to the anatomical characteristics. In this review we discuss recently proposed traction methods for ESD based on the characteristics of various anatomical sites. PMID:27468186

  6. Traction apophysitis of the medial malleolus.

    PubMed

    Ishii, T; Miyagawa, S; Hayashi, K

    1994-09-01

    We report the cases of three children with chronic injuries of the medial tibial malleolus caused by traction injuries during sport. All three had the triad of swelling of the medial malleolus, tenderness over its anterior part, and pain on forced valgus movement of the foot. Radiographs showed bilateral accessory ossification centres and MRI demonstrated partial avulsion or avulsion fracture of the apophyseal cartilage and fragmentation of the accessory centres. A review of 134 young basketball players showed that 25% had tenderness of the anterior medial malleolus. This high rate indicates that traction apophysitis of the medial malleolus is not uncommon in children as a sports-related disorder.

  7. 21 CFR 882.5960 - Skull tongs for traction.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Skull tongs for traction. 882.5960 Section 882...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5960 Skull tongs for traction. (a) Identification. Skull tongs for traction is an instrument used to immobilize a patient with...

  8. 21 CFR 882.5960 - Skull tongs for traction.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Skull tongs for traction. 882.5960 Section 882...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5960 Skull tongs for traction. (a) Identification. Skull tongs for traction is an instrument used to immobilize a patient with...

  9. 21 CFR 882.5960 - Skull tongs for traction.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Skull tongs for traction. 882.5960 Section 882...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5960 Skull tongs for traction. (a) Identification. Skull tongs for traction is an instrument used to immobilize a patient with...

  10. 21 CFR 882.5960 - Skull tongs for traction.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Skull tongs for traction. 882.5960 Section 882...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5960 Skull tongs for traction. (a) Identification. Skull tongs for traction is an instrument used to immobilize a patient with...

  11. 21 CFR 882.5960 - Skull tongs for traction.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Skull tongs for traction. 882.5960 Section 882...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5960 Skull tongs for traction. (a) Identification. Skull tongs for traction is an instrument used to immobilize a patient with...

  12. Facial nerve paralysis after cervical traction.

    PubMed

    So, Edmund Cheung

    2010-10-01

    Cervical traction is a frequently used treatment in rehabilitation clinics for cervical spine problems. This modality works, in principle, by decompressing the spinal cord or its nerve roots by applying traction on the cervical spine through a harness placed over the mandible (Olivero et al., Neurosurg Focus 2002;12:ECP1). Previous reports on treatment complications include lumbar radicular discomfort, muscle injury, neck soreness, and posttraction pain (LaBan et al., Arch Phys Med Rehabil 1992;73:295-6; Lee et al., J Biomech Eng 1996;118:597-600). Here, we report the first case of unilateral facial nerve paralysis developed after 4 wks of intermittent cervical traction therapy. Nerve conduction velocity examination revealed a peripheral-type facial nerve paralysis. Symptoms of facial nerve paralysis subsided after prednisolone treatment and suspension of traction therapy. It is suspected that a misplaced or an overstrained harness may have been the cause of facial nerve paralysis in this patient. Possible causes were (1) direct compression by the harness on the right facial nerve near its exit through the stylomastoid foramen; (2) compression of the right external carotid artery by the harness, causing transient ischemic injury at the geniculate ganglion; or (3) coincidental herpes zoster virus infection or idiopathic Bell's palsy involving the facial nerve.

  13. The Harmonoise/IMAGINE model for traction noise of powered railway vehicles

    NASA Astrophysics Data System (ADS)

    Dittrich, M. G.; Zhang, X.

    2006-06-01

    Traction noise is one of the noise sources of powered railway vehicles such as locomotives, electric- and diesel-powered multiple unit trains and high-speed trains. Especially at speeds below 60 km/h and at idling, but also at acceleration conditions for a wide range of speeds, traction noise can be dominant. This is relevant for noise in residential areas near stations and shunting yards, but in some cases also along the line. The other relevant sources are rolling noise, often dominant between 100 and 250 km/h, aerodynamic noise, which can be dominant above 300 km/h, braking noise, curve squeal and impact noise. The braking system can often technically be considered part of the overall traction system, although acoustically it will often have separate noise sources. In the Harmonoise and IMAGINE EU projects, a generalised prediction model for railway traction noise has been proposed to cover a broad range of powered railway vehicles. The model is one of the prediction modules for overall rail traffic noise, which also covers the other main sources. The traction noise model includes the main operational parameters such as driveshaft speed and power settings, and also takes individual auxiliary components and their duty cycles into account, such as compressors, valves and fans. Source height is included in the model. The level of modelling detail in the many potential traction noise sources has been kept to a minimum, as for the purpose of rail traffic noise prediction it often suffices to model only the dominant sources. Measurement methods are outlined to determine the noise emission spectra, from which extrapolations are made to obtain estimates for different operating conditions.

  14. Vitreopapillary traction in proliferative diabetic vitreoretinopathy

    PubMed Central

    Kroll, P.; Wiegand, W.; Schmidt, J.

    1999-01-01

    AIM—To present the clinical profile of a new entity in advanced proliferative diabetic vitreoretinopathy (PDVR). Mechanisms of vision loss due to vitreopapillary traction on the nasal optic disc are described, followed by an introduction of methods for prevention and treatment in such cases.
METHODS—17 patients with PDVR and traction on the nasal side of the optic disc, pallor of the optic nerve head, and reduced visual acuity were included in the study. Six patients were observed retrospectively and 11 patients prospectively before and after pars plana vitrectomy. Pre- and postoperative examinations included visual acuity, Goldmann's visual field, fluorescein angiography, and measurements of visual evoked potentials (VEP).
RESULTS—During a postoperative follow up period of 3 to 24.5 months (mean 14.5 months) an improvement in optic disc appearance combined with an increased visual acuity (mean increase in VA = 0.171) was observed in 15/17 (88.3%) patients. In addition, 8/17 (47%) of these patients showed higher VEP amplitudes (mean 3.83 µV), and eight (6/8 of the same patients as VEP amplitudes) patients showed a reduction of latency (mean reduction 22.25 ms) during VEP assessment.
CONCLUSION—These results suggest that vitreopapillary traction may damage the anterior optic nerve, via decreased axoplasmatic flow in the optic nerve fibres and/or mechanical reduction of perfusion in the posterior ciliary arteries. The effects of each mechanism appear to be reversible, but in the long term might lead to irreversible optic nerve atrophy. Therefore, in patients with vitreopapillary traction, early vitrectomy should be considered as a method to prevent optic neuropathy.

 Keywords: diabetic vitreopapillary traction; proliferative diabetic vitreoretinopathy; vitrectomy PMID:10365029

  15. Micropatterning tractional forces in living cells

    NASA Technical Reports Server (NTRS)

    Wang, Ning; Ostuni, Emanuele; Whitesides, George M.; Ingber, Donald E.

    2002-01-01

    Here we describe a method for quantifying traction in cells that are physically constrained within micron-sized adhesive islands of defined shape and size on the surface of flexible polyacrylamide gels that contain fluorescent microbeads (0.2-microm diameter). Smooth muscle cells were plated onto square (50 x 50 microm) or circular (25- or 50-microm diameter) adhesive islands that were created on the surface of the gels by applying a collagen coating through microengineered holes in an elastomeric membrane that was later removed. Adherent cells spread to take on the size and shape of the islands and cell tractions were quantitated by mapping displacement fields of the fluorescent microbeads within the gel. Cells on round islands did not exhibit any preferential direction of force application, but they exerted their strongest traction at sites where they formed protrusions. When cells were confined to squares, traction was highest in the corners both in the absence and presence of the contractile agonist, histamine, and cell protrusions were also observed in these regions. Quantitation of the mean traction exerted by cells cultured on the different islands revealed that cell tension increased as cell spreading was promoted. These results provide a mechanical basis for past studies that demonstrated a similar correlation between spreading and growth within various anchorage-dependent cells. This new approach for analyzing the spatial distribution of mechanical forces beneath individual cells that are experimentally constrained to defined sizes and shapes may provide additional insight into the biophysical basis of cell regulation. Copyright 2002 Wiley-Liss, Inc.

  16. A Novel Transverse Flux Machine for Vehicle Traction Applications

    SciTech Connect

    Wan, Zhao; Ahmed, Adeeb; Husain, Iqbal; Muljadi, Eduard

    2015-10-05

    A novel transverse flux machine topology for electric vehicle traction application using ferrite magnets is presented in this paper. The proposed transverse flux topology utilizes novel magnet arrangements in the rotor that are similar to Halbach-array to boost flux linkage; on the stator side, cores are alternately arranged around a pair of ring windings in each phase to make use of the entire rotor flux that eliminates end windings. Analytical design considerations and finite element methods are used for an optimized design of a scooter in-wheel motor. Simulation results from Finite Element Analysis (FEA) show the motor achieved comparable torque density to conventional rare-earth permanent magnet machines. This machine is a viable candidate for direct drive applications with low cost and high torque density.

  17. Novel Transverse Flux Machine for Vehicle Traction Applications: Preprint

    SciTech Connect

    Wan, Z.; Ahmed, A.; Husain, I.; Muljadi, E.

    2015-04-02

    A novel transverse flux machine topology for electric vehicle traction applications using ferrite magnets is presented in this paper. The proposed transverse flux topology utilizes novel magnet arrangements in the rotor that are similar to the Halbach array to boost flux linkage; on the stator side, cores are alternately arranged around a pair of ring windings in each phase to make use of the entire rotor flux that eliminates end windings. Analytical design considerations and finite-element methods are used for an optimized design of a scooter in-wheel motor. Simulation results from finite element analysis (FEA) show that the motor achieved comparable torque density to conventional rare-earth permanent magnet (PM) machines. This machine is a viable candidate for direct-drive applications with low cost and high torque density.

  18. Intercellular Stress Reconstitution from Traction Force Data

    PubMed Central

    Zimmermann, Juliane; Hayes, Ryan L.; Basan, Markus; Onuchic, José N.; Rappel, Wouter-Jan; Levine, Herbert

    2014-01-01

    Cells migrate collectively during development, wound healing, and cancer metastasis. Recently, a method has been developed to recover intercellular stress in monolayers from measured traction forces upon the substrate. To calculate stress maps in two dimensions, the cell sheet was assumed to behave like an elastic material, and it remains unclear to what extent this assumption is valid. In this study, we simulate our recently developed model for collective cell migration, and compute intercellular stress maps using the method employed in the experiments. We also compute these maps using a method that does not depend on the traction forces or material properties. The two independently obtained stress patterns agree well for the parameters we have probed and provide a verification of the validity of the experimental method. PMID:25099794

  19. Validation tool for traction force microscopy.

    PubMed

    Jorge-Peñas, A; Muñoz-Barrutia, A; de-Juan-Pardo, E M; Ortiz-de-Solorzano, C

    2015-01-01

    Traction force microscopy (TFM) is commonly used to estimate cells' traction forces from the deformation that they cause on their substrate. The accuracy of TFM highly depends on the computational methods used to measure the deformation of the substrate and estimate the forces, and also on the specifics of the experimental set-up. Computer simulations can be used to evaluate the effect of both the computational methods and the experimental set-up without the need to perform numerous experiments. Here, we present one such TFM simulator that addresses several limitations of the existing ones. As a proof of principle, we recreate a TFM experimental set-up, and apply a classic 2D TFM algorithm to recover the forces. In summary, our simulator provides a valuable tool to study the performance, refine experimentally, and guide the extraction of biological conclusions from TFM experiments. PMID:24697293

  20. Three-Dimensional Reflectance Traction Microscopy

    PubMed Central

    Jones, Christopher A. R.; Groves, Nicholas Scott; Sun, Bo

    2016-01-01

    Cells in three-dimensional (3D) environments exhibit very different biochemical and biophysical phenotypes compared to the behavior of cells in two-dimensional (2D) environments. As an important biomechanical measurement, 2D traction force microscopy can not be directly extended into 3D cases. In order to quantitatively characterize the contraction field, we have developed 3D reflectance traction microscopy which combines confocal reflection imaging and partial volume correlation postprocessing. We have measured the deformation field of collagen gel under controlled mechanical stress. We have also characterized the deformation field generated by invasive breast cancer cells of different morphologies in 3D collagen matrix. In contrast to employ dispersed tracing particles or fluorescently-tagged matrix proteins, our methods provide a label-free, computationally effective strategy to study the cell mechanics in native 3D extracellular matrix. PMID:27304456

  1. Traction in smooth muscle cells varies with cell spreading

    NASA Technical Reports Server (NTRS)

    Tolic-Norrelykke, Iva Marija; Wang, Ning

    2005-01-01

    Changes in cell shape regulate cell growth, differentiation, and apoptosis. It has been suggested that the regulation of cell function by the cell shape is a result of the tension in the cytoskeleton and the distortion of the cell. Here we explore the association between cell-generated mechanical forces and the cell morphology. We hypothesized that the cell contractile force is associated with the degree of cell spreading, in particular with the cell length. We measured traction fields of single human airway smooth muscle cells plated on a polyacrylamide gel, in which fluorescent microbeads were embedded to serve as markers of gel deformation. The traction exerted by the cells at the cell-substrate interface was determined from the measured deformation of the gel. The traction was measured before and after treatment with the contractile agonist histamine, or the relaxing agonist isoproterenol. The relative increase in traction induced by histamine was negatively correlated with the baseline traction. On the contrary, the relative decrease in traction due to isoproterenol was independent of the baseline traction, but it was associated with cell shape: traction decreased more in elongated than in round cells. Maximum cell width, mean cell width, and projected area of the cell were the parameters most tightly coupled to both baseline and histamine-induced traction in this study. Wide and well-spread cells exerted larger traction than slim cells. These results suggest that cell contractility is controlled by cell spreading.

  2. Orthodontic Traction of Impacted Canine Using Cantilever

    PubMed Central

    Gonçalves, João Roberto; Cassano, Daniel Serra; Bianchi, Jonas

    2016-01-01

    The impaction of the maxillary canines causes relevant aesthetic and functional problems. The multidisciplinary approach to the proper planning and execution of orthodontic traction of the element in question is essential. Many strategies are cited in the literature; among them is the good biomechanical control in order to avoid possible side effects. The aim of this paper is to present a case report in which a superior canine impacted by palatine was pulled out with the aid of the cantilever on the Segmented Arch Technique (SAT) concept. A 14.7-year-old female patient appeared at clinic complaining about the absence of the upper right permanent canine. The proposed treatment prioritized the traction of the upper right canine without changing the occlusion and aesthetics. For this, it only installed the upper fixed appliance (Roth with slot 0.018), opting for SAT in order to minimize unwanted side effects. The use of cantilever to the traction of the upper right canine has enabled an efficient and predictable outcome, because it is of statically determined mechanics. PMID:27800192

  3. [Myopic traction maculopathy - vitreoretinal traction syndrome in high myopic eyes and posterior staphyloma].

    PubMed

    Müller, B; Joussen, A M

    2011-09-01

    The pathology of the posterior pole in high myopic eyes is characterised by scleral thinning and staphyloma associated with structural changes of the retina. Epiretinal membranes and epiretinal traction together with partial separation of the ILM result in myopic foveoschisis and posterior tractional detachment with myopic macular holes. Foveal detachment and retinoschisis in highly myopic eyes may resolve after vitrectomy with ILM peeling: however, there is a considerable risk for the development of macular hole formation. Skleral buckling surgery is currently regaining interest and allows one to reduce the tractional forces in selected cases. While reading visual acuity is usually not regained after macular hole development, prophylactic measures should be considered for the fellow eye. Vitreous surgery might have a rationale as prophylactic treatment for highly myopic eyes at high risk of macular hole development; however, this needs to be weighed against possible surgical complications.

  4. Fibroblast traction as a mechanism for collagen morphogenesis

    NASA Astrophysics Data System (ADS)

    Harris, Albert K.; Stopak, David; Wild, Patricia

    1981-03-01

    To make visible the traction forces exerted by individual cells, we have previously developed a method of culturing them on thin distortable sheets of silicone rubber1. We have now used this method to compare the forces exerted by various differentiated cell types and have examined the effects of cellular traction on re-precipitated collagen matrices. We find that the strength of cellular traction differs greatly between cell types and this traction is paradoxically weakest in the most mobile and invasive cells (leukocytes and nerve growth cones). Untransformed fibroblasts exert forces very much larger than those actually needed for locomotion. This strong traction distorts collagen gels dramatically, creating patterns similar to tendons and organ capsules. We propose that this morphogenetic rearrangement of extracellular matrices is the primary function of fibroblast traction and explains its excessive strength.

  5. Measurement of cell traction forces with ImageJ.

    PubMed

    Martiel, Jean-Louis; Leal, Aldo; Kurzawa, Laetitia; Balland, Martial; Wang, Irene; Vignaud, Timothée; Tseng, Qingzong; Théry, Manuel

    2015-01-01

    The quantification of cell traction forces requires three key steps: cell plating on a deformable substrate, measurement of substrate deformation, and the numerical estimation of the corresponding cell traction forces. The computing steps to measure gel deformation and estimate the force field have somehow limited the adoption of this method in cell biology labs. Here we propose a set of ImageJ plug-ins so that every lab equipped with a fluorescent microscope can measure cell traction forces.

  6. Grain Boundary Traction Signatures: Quantitative Predictors of Dislocation Emission

    NASA Astrophysics Data System (ADS)

    Li, Ruizhi; Chew, Huck Beng

    2016-08-01

    We introduce the notion of continuum-equivalent traction fields as local quantitative descriptors of the grain boundary interface. These traction-based descriptors are capable of predicting the critical stresses to trigger dislocation emissions from ductile ⟨110 ⟩ symmetrical-tilt nickel grain boundaries. We show that Shockley partials are emitted when the grain boundary tractions, in combination with external tensile loading, generate a resolved shear stress to cause dislocation slip. The relationship between the local grain boundary tractions and the grain boundary energy is established.

  7. Grain Boundary Traction Signatures: Quantitative Predictors of Dislocation Emission.

    PubMed

    Li, Ruizhi; Chew, Huck Beng

    2016-08-19

    We introduce the notion of continuum-equivalent traction fields as local quantitative descriptors of the grain boundary interface. These traction-based descriptors are capable of predicting the critical stresses to trigger dislocation emissions from ductile ⟨110⟩ symmetrical-tilt nickel grain boundaries. We show that Shockley partials are emitted when the grain boundary tractions, in combination with external tensile loading, generate a resolved shear stress to cause dislocation slip. The relationship between the local grain boundary tractions and the grain boundary energy is established. PMID:27588865

  8. Simplified fatigue life analysis for traction drive contacts

    NASA Technical Reports Server (NTRS)

    Rohn, D. A.; Loewenthal, S. H.; Coy, J. J.

    1980-01-01

    A simplified fatigue life analysis for traction drive contacts of arbitrary geometry is presented. The analysis is based on the Lundberg-Palmgren theory used for rolling-element bearings. The effects of torque, element size, speed, contact ellipse ratio, and the influence of traction coefficient are shown. The analysis shows that within the limits of the available traction coefficient, traction contacts exhibit longest life at high speeds. Multiple, load-sharing roller arrangements have an advantageous effect on system life, torque capacity, power-to-weight ratio and size.

  9. Pulse charging of lead-acid traction cells

    NASA Technical Reports Server (NTRS)

    Smithrick, J. J.

    1980-01-01

    Pulse charging, as a method of rapidly and efficiently charging 300 amp-hour lead-acid traction cells for an electric vehicle application was investigated. A wide range of charge pulse current square waveforms were investigated and the results were compared to constant current charging at the time averaged pulse current values. Representative pulse current waveforms were: (1) positive waveform-peak charge pulse current of 300 amperes (amps), discharge pulse-current of zero amps, and a duty cycle of about 50%; (2) Romanov waveform-peak charge pulse current of 300 amps, peak discharge pulse current of 15 amps, and a duty of 50%; and (3) McCulloch waveform peak charge pulse current of 193 amps, peak discharge pulse current of about 575 amps, and a duty cycle of 94%. Experimental results indicate that on the basis of amp-hour efficiency, pulse charging offered no significant advantage as a method of rapidly charging 300 amp-hour lead-acid traction cells when compared to constant current charging at the time average pulse current value. There were, however, some disadvantages of pulse charging in particular a decrease in charge amp-hour and energy efficiencies and an increase in cell electrolyte temperature. The constant current charge method resulted in the best energy efficiency with no significant sacrifice of charge time or amp-hour output. Whether or not pulse charging offers an advantage over constant current charging with regard to the cell charge/discharge cycle life is unknown at this time.

  10. Integrated Cooling System for Induction Motor Traction Drives, CARAT Program Phase Two Final Report

    SciTech Connect

    Konrad, Charles E.

    2002-12-03

    This Program is directed toward improvements in electric vehicle/hybrid electric vehicle traction systems, and in particular, the development of a low cost, highly efficient, compact traction motor-controller system targeted for high volume automotive use. Because of the complex inter-relationships between the motor and the controller, the combination of motor and controller must be considered as a system in the design and evaluation of overall cost and performance. The induction motor is ideally suited for use as a traction motor because of its basic ruggedness, low cost, and high efficiency. As one can see in Figure 1.1, the induction motor traction drive has been continually evolving through a succession of programs spanning the past fifteen years. VPT marketed an induction motor-based traction drive system, the EV2000, which proved to be a reliable, high performance system that was used in a wide range of vehicles. The EV2000 drives evolved from the Modular Electric Vehicle Program (MEVP) and has been used in vehicles ranging in size from 3,000 lb. autos and utility vans, to 32,000 lb. city transit buses. Vehicles powered by the EV2000 induction motor powertrain have accumulated over 2 million miles of service. The EV2000 induction motor system represents 1993 state-of-the-art technology, and evolved from earlier induction motor programs that drove induction motor speeds up to 15,000 rpm to reduce the motor size and cost. It was recognized that the improvements in power density and motor cost sought in the PNGV program could only be achieved through increases in motor speed. Esson’s Rule for motor power clearly states that the power obtainable from a given motor design is the product of motor speed and volume. In order to meet the CARAT Program objectives, the maximum speed goal of the induction motor designed in this Program was increased from 15,000 rpm to 20,000 rpm while maintaining the efficiency and durability demonstrated by lower speed designs done in

  11. Super-Resolved Traction Force Microscopy (STFM).

    PubMed

    Colin-York, Huw; Shrestha, Dilip; Felce, James H; Waithe, Dominic; Moeendarbary, Emad; Davis, Simon J; Eggeling, Christian; Fritzsche, Marco

    2016-04-13

    Measuring small forces is a major challenge in cell biology. Here we improve the spatial resolution and accuracy of force reconstruction of the well-established technique of traction force microscopy (TFM) using STED microscopy. The increased spatial resolution of STED-TFM (STFM) allows a greater than 5-fold higher sampling of the forces generated by the cell than conventional TFM, accessing the nano instead of the micron scale. This improvement is highlighted by computer simulations and an activating RBL cell model system.

  12. DETAIL OF TRACTION CABLE ENGAGEMENT DEVICE. SMALL, KNOBBED LEVER ON ...

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

    DETAIL OF TRACTION CABLE ENGAGEMENT DEVICE. SMALL, KNOBBED LEVER ON BUCKET HANGER WAS PULLED DOWN BY A CAMEL (FIXED CAM RAIL AT CENTER) AS BUCKET ROLLED PAST IT, CAUSING A CLAMP TO CLOSE AGAINST TRACTION CABLE. A SIMILAR CAMEL (NO LONGER EXTANT) DISENGAGED CLAMP ON RECEIVING SIDE. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  13. Traction in elastohydrodynamic line contacts for two synthesized hydrocarbon fluids

    NASA Technical Reports Server (NTRS)

    Trachman, E. G.; Cheng, H. S.

    1973-01-01

    The paper describes the disk machine designed and constructed for the investigation of the traction in elastohydrodynamic line contacts for two synthesized hydrocarbon fluids. The results of this experimental study are presented and compared with the theoretical predictions of traction according to the thermal and non-Newtonian theory recently presented by the authors.

  14. Development of Traction Drive Motors for the Toyota Hybrid System

    NASA Astrophysics Data System (ADS)

    Kamiya, Munehiro

    Toyota Motor Corporation developed in 2005 a new hybrid system for a large SUV. This system included the new development of a high-speed traction drive motor achieving a significant increase in power weight ratio. This paper provides an overview of the hybrid system, discusses the characteristics required of a traction drive motor, and presents the technologies employed in the developed motor.

  15. High-Resolution Traction Force Microscopy

    PubMed Central

    Plotnikov, Sergey V.; Sabass, Benedikt; Schwarz, Ulrich S.; Waterman, Clare M.

    2015-01-01

    Cellular forces generated by the actomyosin cytoskeleton and transmitted to the extracellular matrix (ECM) through discrete, integrin-based protein assemblies, that is, focal adhesions, are critical to developmental morphogenesis and tissue homeostasis, as well as disease progression in cancer. However, quantitative mapping of these forces has been difficult since there has been no experimental technique to visualize nanonewton forces at submicrometer spatial resolution. Here, we provide detailed protocols for measuring cellular forces exerted on two-dimensional elastic substrates with a high-resolution traction force microscopy (TFM) method. We describe fabrication of polyacrylamide substrates labeled with multiple colors of fiducial markers, functionalization of the substrates with ECM proteins, setting up the experiment, and imaging procedures. In addition, we provide the theoretical background of traction reconstruction and experimental considerations important to design a high-resolution TFM experiment. We describe the implementation of a new algorithm for processing of images of fiducial markers that are taken below the surface of the substrate, which significantly improves data quality. We demonstrate the application of the algorithm and explain how to choose a regularization parameter for suppression of the measurement error. A brief discussion of different ways to visualize and analyze the results serves to illustrate possible uses of high-resolution TFM in biomedical research. PMID:24974038

  16. Life analysis of multiroller planetary traction drive

    NASA Technical Reports Server (NTRS)

    Coy, J. J.; Rohn, D. A.; Loewenthal, S. H.

    1981-01-01

    A contact fatigue life analysis was performed for a constant ratio, Nasvytis Multiroller Traction Drive. The analysis was based on the Lundberg-Palmgren method for rolling element bearing life prediction. Life adjustment factors for materials, processing, lubrication and traction were included. The 14.7 to 1 ratio drive consisted of a single stage planetary configuration with two rows of stepped planet rollers of five rollers per row, having a roller cluster diameter of approximately 0.21 m, a width of 0.06 m and a weight of 9 kg. Drive system 10 percent life ranged from 18,800 hours at 16.6 kW (22.2 hp) and 25,000 rpm sun roller speed, to 305 hours at maximum operating conditions of 149 kw (200 hp) and 75,000 rpm sun roller speed. The effect of roller diameter and roller center location on life were determined. It was found that an optimum life geometry exists.

  17. Towards Single Cell Traction Microscopy within 3D Collagen Matrices

    PubMed Central

    Hall, Matthew S.; Long, Rong; Feng, Xinzeng; Huang, YuLing; Hui, Chung-Yuen; Wu, Mingming

    2013-01-01

    Mechanical interaction between the cell and its extracellular matrix (ECM) regulates cellular behaviors, including proliferation, differentiation, adhesion, and migration. Cells require the three dimensional (3D) architectural support of the ECM to perform physiologically realistic functions. However, current understanding of cell-ECM and cell-cell mechanical interactions is largely derived from 2D cell traction force microscopy, in which cells are cultured on a flat substrate. 3D cell traction microscopy is emerging for mapping traction fields of single animal cells embedded in either synthetic or natively derived fibrous gels. We discuss here the development of 3D cell traction microscopy, its current limitations, and perspectives on the future of this technology. Emphasis is placed on strategies for applying 3D cell traction microscopy to individual tumor cells migration within collagen gels. PMID:23806281

  18. Toward single cell traction microscopy within 3D collagen matrices

    SciTech Connect

    Hall, Matthew S.; Long, Rong; Feng, Xinzeng; Huang, YuLing; Hui, Chung-Yuen; Wu, Mingming

    2013-10-01

    Mechanical interaction between the cell and its extracellular matrix (ECM) regulates cellular behaviors, including proliferation, differentiation, adhesion, and migration. Cells require the three-dimensional (3D) architectural support of the ECM to perform physiologically realistic functions. However, current understanding of cell–ECM and cell–cell mechanical interactions is largely derived from 2D cell traction force microscopy, in which cells are cultured on a flat substrate. 3D cell traction microscopy is emerging for mapping traction fields of single animal cells embedded in either synthetic or natively derived fibrous gels. We discuss here the development of 3D cell traction microscopy, its current limitations, and perspectives on the future of this technology. Emphasis is placed on strategies for applying 3D cell traction microscopy to individual tumor cell migration within collagen gels. - Highlights: • Review of the current state of the art in 3D cell traction force microscopy. • Bulk and micro-characterization of remodelable fibrous collagen gels. • Strategies for performing 3D cell traction microscopy within collagen gels.

  19. Rapid, efficient charging of lead-acid and nickel-zinc traction cells

    NASA Technical Reports Server (NTRS)

    Smithrick, J. J.

    1978-01-01

    Lead-acid and nickel-zinc traction cells were rapidly and efficiently charged using a high rate tapered direct current (HRTDC) charge method which could possibly be used for on-the-road service recharge of electric vehicles. The HRTDC method takes advantage of initial high cell charge acceptance and uses cell gassing rate and temperature as an indicator of charging efficiency. On the average, in these preliminary tests, 300 amp-hour nickel-zinc traction cells were given a HRTDC (initial current 500 amps, final current 100 amps) to 78 percent of rated amp-hour capacity within 53 minutes at an amp-hour efficiency of 92 percent and an energy efficiency of 52 percent. Three hundred amp-hour lead-acid traction cells were charged to 69 percent of rated amp-hour capacity within 46 minutes at an amp-hour efficiency of 91 percent with an energy efficiency of 64 percent. In order to find ways to further decrease the recharge times, the effect of periodically (0 to 400 Hz) pulse discharging cells during a constant current charging process (94% duty cycle) was investigated. Preliminary data indicate no significant effect of this type of pulse discharging during charge on charge acceptance of lead-acid or nickel-zinc cells.

  20. Energy and wear optimisation of train longitudinal dynamics and of traction and braking systems

    NASA Astrophysics Data System (ADS)

    Conti, R.; Galardi, E.; Meli, E.; Nocciolini, D.; Pugi, L.; Rindi, A.

    2015-05-01

    Traction and braking systems deeply affect longitudinal train dynamics, especially when an extensive blending phase among different pneumatic, electric and magnetic devices is required. The energy and wear optimisation of longitudinal vehicle dynamics has a crucial economic impact and involves several engineering problems such as wear of braking friction components, energy efficiency, thermal load on components, level of safety under degraded or adhesion conditions (often constrained by the current regulation in force on signalling or other safety-related subsystem). In fact, the application of energy storage systems can lead to an efficiency improvement of at least 10% while, as regards the wear reduction, the improvement due to distributed traction systems and to optimised traction devices can be quantified in about 50%. In this work, an innovative integrated procedure is proposed by the authors to optimise longitudinal train dynamics and traction and braking manoeuvres in terms of both energy and wear. The new approach has been applied to existing test cases and validated with experimental data provided by Breda and, for some components and their homologation process, the results of experimental activities derive from cooperation performed with relevant industrial partners such as Trenitalia and Italcertifer. In particular, simulation results are referred to the simulation tests performed on a high-speed train (Ansaldo Breda Emu V250) and on a tram (Ansaldo Breda Sirio Tram). The proposed approach is based on a modular simulation platform in which the sub-models corresponding to different subsystems can be easily customised, depending on the considered application, on the availability of technical data and on the homologation process of different components.

  1. An affordable humanitarian mine detector

    NASA Astrophysics Data System (ADS)

    Daniels, David J.; Curtis, Paul; Amin, Rajan; Dittmer, Jon

    2004-09-01

    This paper describes the further development of the MINETECT affordable humanitarian mine detector produced by ERA Technology with sponsorship from the UK Department for International Development. Using a radically different patented approach from conventional ground penetrating radar (GPR) designs in terms of the man machine interface, MINETECT offers simplicity of use and affordability, both key factors in humanitarian demining operations. Following trials in 2002 and reported at SPIE 2002, further development work including research on classifying mines, based on data from planned trials in the United Kingdom, is presented. MINETECT has the capability of detecting completely non-metallic mines and offers a considerable improvement in hand-held mine detection.

  2. Mechanical Lumbar Traction: What Is Its Place in Clinical Practice?

    PubMed

    2016-03-01

    Summary evidence concludes that mechanical lumbar traction is not effective for treating acute or chronic nonspecific low back pain (LBP). However, many physical therapists continue to use it, primarily as an additional modality. Indeed, expert clinical opinion, theoretical models, and some research evidence suggest that certain patients with LBP respond positively to traction. A study published in the March 2016 issue of JOSPT investigates the effectiveness of traction in prone as an adjunct to an extension-oriented exercise program in patients with LBP and leg pain and explores whether a previously identified set of patient characteristics is associated with better outcomes from traction. In this Perspectives for Practice, the authors explain the impact of their findings for clinicians treating these patients. PMID:26928736

  3. A Novel Technique for Post-Prostatectomy Catheter Traction

    PubMed Central

    Akhavizadegan, Hamed

    2016-01-01

    Background Prostate traction is one way to control post-prostatectomy bleeding. The most popular method involves traction with a catheter fixed to the thigh with adhesive bands. However, this method has its own drawbacks. Objectives We aimed to simplify this traction procedure and to overcome its disadvantages. Patients and Methods From 2007 - 2015, a new method was used to control post-prostatectomy bleeding in 152 patients. This technique involved inducing pressure on the prostate neck with an indwelling catheter attached to a partially filled urine bag to control bleeding after a prostatectomy. Results The new method effectively controlled post-prostatectomy bleeding. A few patients required surgical intervention. Conclusions Post-prostatectomy catheter traction using a semi-filled urine bag was an acceptable alternative to the standard method to control post-operative bleeding. PMID:27703955

  4. Developing Strategies for Affordable Bandwidth.

    ERIC Educational Resources Information Center

    Educause Quarterly, 2000

    2000-01-01

    Written by Educause's Net@EDU Broadband Pricing Working Group, this article discusses what institutions of higher education can do to develop good partnerships with broadband vendors in order to negotiate affordable pricing for increased bandwidth. Describes problems with the marketplace, examples from a few universities, and points to remember…

  5. Affordable comfort 95 - investing in our energy future

    SciTech Connect

    1995-12-31

    This report describes the topics from the conference on Affordable Comfort, held March 26-31, 1995. Topics are concerned with energy efficiency in homes, retrofitting, weatherization, and monitoring of appliances, heating, and air conditioning systems for performance, as well as topics on electric utilities.

  6. Global affordability of fluoride toothpaste

    PubMed Central

    Goldman, Ann S; Yee, Robert; Holmgren, Christopher J; Benzian, Habib

    2008-01-01

    Objective Dental caries remains the most common disease worldwide and the use of fluoride toothpaste is a most effective preventive public health measure to prevent it. Changes in diets following globalization contribute to the development of dental caries in emerging economies. The aim of this paper is to compare the cost and relative affordability of fluoride toothpaste in high-, middle- and low-income countries. The hypothesis is that fluoride toothpaste is not equally affordable in high-, middle- and low-income countries. Methods Data on consumer prices of fluoride toothpastes were obtained from a self-completion questionnaire from 48 countries. The cost of fluoride toothpaste in high-, middle- and low-income countries was compared and related to annual household expenditure as well as to days of work needed to purchase the average annual usage of toothpaste per head. Results The general trend seems to be that the proportion of household expenditure required to purchase the annual dosage of toothpaste increases as the country's per capita household expenditure decreases. While in the UK for the poorest 30% of the population only 0.037 days of household expenditure is needed to purchase the annual average dosage (182.5 g) of the lowest cost toothpaste, 10.75 days are needed in Kenya. The proportion of annual household expenditure ranged from 0.02% in the UK to 4% in Zambia to buy the annual average amount of lowest cost toothpaste per head. Conclusion Significant inequalities in the affordability of this essential preventive care product indicate the necessity for action to make it more affordable. Various measures to improve affordability based on experiences from essential pharmaceuticals are proposed. PMID:18554382

  7. Keratocytes generate traction forces in two phases.

    PubMed

    Burton, K; Park, J H; Taylor, D L

    1999-11-01

    Forces generated by goldfish keratocytes and Swiss 3T3 fibroblasts have been measured with nanonewton precision and submicrometer spatial resolution. Differential interference contrast microscopy was used to visualize deformations produced by traction forces in elastic substrata, and interference reflection microscopy revealed sites of cell-substratum adhesions. Force ranged from a few nanonewtons at submicrometer spots under the lamellipodium to several hundred nanonewtons under the cell body. As cells moved forward, centripetal forces were applied by lamellipodia at sites that remained stationary on the substratum. Force increased and abruptly became lateral at the boundary of the lamellipodium and the cell body. When the cell retracted at its posterior margin, cell-substratum contact area decreased more rapidly than force, so that stress (force divided by area) increased as the cell pulled away. An increase in lateral force was associated with widening of the cell body. These mechanical data suggest an integrated, two-phase mechanism of cell motility: (1) low forces in the lamellipodium are applied in the direction of cortical flow and cause the cell body to be pulled forward; and (2) a component of force at the flanks pulls the rear margins forward toward the advancing cell body, whereas a large lateral component contributes to detachment of adhesions without greatly perturbing forward movement. PMID:10564269

  8. Making personalized medicine more affordable.

    PubMed

    Aronson, Naomi

    2015-06-01

    Precision medicine holds promise to solve the conundrums of clinical care. Foremost is the well-known but vexing problem of heterogeneity and the tyranny of the mean. Who will respond to a treatment? How can patients avoid the harms of treatments that will not work for them? And if we know who to treat, will that make care more efficient and less costly? But the converse can also be true: treatments become more expensive as the costs of development must be distributed across smaller populations. Next-generation sequencing is making genetic testing radically cheaper. But the costs of medical tests also include false-positive results, incidental findings, and the cascade of follow-up. The affordability of precision medicine is intertwined with the broader issue of affordability of our healthcare system, and will require all stakeholders to assume stewardship for access and sustainability. PMID:25728478

  9. Optics learning through affordable kit

    NASA Astrophysics Data System (ADS)

    P, Anusha N.; Shaji, Chitra; Sharan, Alok

    2014-10-01

    An affordable kit which helps to understand some of the optical phenomena qualitatively and quantitatively is presented in this paper. It supplements optics taught in classes. The kit consists of equipments which are available in the market at nominal cost such as laser pointer, lenses, glass plates, razor blades, coins, ball bearing etc. Experiments which come under wave optics (interference and diffraction) and ray optics (reflection and refraction) are explained using this kit.

  10. Optics learning through affordable kit

    SciTech Connect

    P, Anusha N E-mail: chitrashaji@gmail.com Shaji, Chitra E-mail: chitrashaji@gmail.com Sharan, Alok E-mail: chitrashaji@gmail.com

    2014-10-15

    An affordable kit which helps to understand some of the optical phenomena qualitatively and quantitatively is presented in this paper. It supplements optics taught in classes. The kit consists of equipments which are available in the market at nominal cost such as laser pointer, lenses, glass plates, razor blades, coins, ball bearing etc. Experiments which come under wave optics (interference and diffraction) and ray optics (reflection and refraction) are explained using this kit.

  11. Advantages of diabetic tractional retinal detachment repair

    PubMed Central

    Sternfeld, Amir; Axer-Siegel, Ruth; Stiebel-Kalish, Hadas; Weinberger, Dov; Ehrlich, Rita

    2015-01-01

    Purpose To evaluate the outcomes and complications of patients with diabetic tractional retinal detachment (TRD) treated with pars plana vitrectomy (PPV). Patients and methods We retrospectively studied a case series of 24 eyes of 21 patients at a single tertiary, university-affiliated medical center. A review was carried out on patients who underwent PPV for the management of TRD due to proliferative diabetic retinopathy from October 2011 to November 2013. Preoperative and final visual outcomes, intraoperative and postoperative complications, and medical background were evaluated. Results A 23 G instrumentation was used in 23 eyes (95.8%), and a 25 G instrumentation in one (4.2%). Mean postoperative follow-up time was 13.3 months (4–30 months). Visual acuity significantly improved from logarithm of the minimum angle of resolution (LogMAR) 1.48 to LogMAR 1.05 (P<0.05). Visual acuity improved by ≥3 lines in 75% of patients. Intraoperative complications included iatrogenic retinal breaks in seven eyes (22.9%) and vitreal hemorrhage in nine eyes (37.5%). In two eyes, one sclerotomy was enlarged to 20 G (8.3%). Postoperative complications included reoperation in five eyes (20.8%) due to persistent subretinal fluid (n=3), vitreous hemorrhage (n=1), and dislocated intraocular lens (n=1). Thirteen patients (54.2%) had postoperative vitreous hemorrhage that cleared spontaneously, five patients (20.8%) required antiglaucoma medications for increased intraocular pressure, seven patients (29.2%) developed an epiretinal membrane, and two patients (8.3%) developed a macular hole. Conclusion Patients with diabetic TRD can benefit from PPV surgery. Intraoperative and postoperative complications can be attributed to the complexity of this disease. PMID:26604667

  12. Flow mechanotransduction regulates traction forces, intercellular forces, and adherens junctions

    PubMed Central

    Ting, Lucas H.; Jahn, Jessica R.; Jung, Joon I.; Shuman, Benjamin R.; Feghhi, Shirin; Han, Sangyoon J.; Rodriguez, Marita L.

    2012-01-01

    Endothelial cells respond to fluid shear stress through mechanotransduction responses that affect their cytoskeleton and cell-cell contacts. Here, endothelial cells were grown as monolayers on arrays of microposts and exposed to laminar or disturbed flow to examine the relationship among traction forces, intercellular forces, and cell-cell junctions. Cells under laminar flow had traction forces that were higher than those under static conditions, whereas cells under disturbed flow had lower traction forces. The response in adhesion junction assembly matched closely with changes in traction forces since adherens junctions were larger in size for laminar flow and smaller for disturbed flow. Treating the cells with calyculin-A to increase myosin phosphorylation and traction forces caused an increase in adherens junction size, whereas Y-27362 cause a decrease in their size. Since tugging forces across cell-cell junctions can promote junctional assembly, we developed a novel approach to measure intercellular forces and found that these forces were higher for laminar flow than for static or disturbed flow. The size of adherens junctions and tight junctions matched closely with intercellular forces for these flow conditions. These results indicate that laminar flow can increase cytoskeletal tension while disturbed flow decreases cytoskeletal tension. Consequently, we found that changes in cytoskeletal tension in response to shear flow conditions can affect intercellular tension, which in turn regulates the assembly of cell-cell junctions. PMID:22447948

  13. Impact of separator design on battery performance in traction applications

    NASA Astrophysics Data System (ADS)

    Brilmyer, G. H.

    The lead-acid battery continues to be the battery of choice for traction applications. Golf carts, lift-trucks and automatic guided vehicles are only a few of the traction-related markets which depend on the lead-acid battery for their continued growth and success. Throughout the world, traction battery manufacturers use a wide range of grid designs, grid alloys, paste formulations, separators and other features to optimize the deep-cycle performance of their products. In this complex array of design features, the least understood parameter is most likely the battery separator. Though somewhat inconspicuous by nature, the traction-battery separator can, if properly selected, play a key role in performance, by extending the life of both the positive and negative plates while at the same time reducing battery maintenance and power requirements for recharging. This paper discusses the various design features of a battery separator and describes how such features may be used to effect the performance and life of the traction battery. Separator porosity, material composition, backweb thickness, rib dimensions and the use of attached glass mats are some of the controlled variables.

  14. Smoking Bans in Affordable Housing Benefit All

    MedlinePlus

    ... 160501.html Smoking Bans in Affordable Housing Benefit All: Study Secondhand exposure lowered, and smokers more likely ... residents of eight affordable housing properties in Minnesota. All the properties prohibited smoking indoors and three also ...

  15. Can China afford rapid aging?

    PubMed

    Jiang, Quanbao; Yang, Shucai; Sánchez-Barricarte, Jesús J

    2016-01-01

    China's rapid aging has caused widespread concern, but it seems that the situations and consequences of rapid aging are not adequately acknowledged. This study analyzed the problem of ageing in China from the aspects of elderly people's health status, income source, daily care, suicide, the weak social security system in terms of pension, health expenses, and long-term care costs as well as incoming accelerating ageing process in China. All these factors indicate that it is difficult for China to afford the issue of a rapidly aging population. PMID:27478724

  16. Perceiving Affordances for Fitting through Apertures

    ERIC Educational Resources Information Center

    Ishak, Shaziela; Adolph, Karen E.; Lin, Grace C.

    2008-01-01

    Affordances--possibilities for action--are constrained by the match between actors and their environments. For motor decisions to be adaptive, affordances must be detected accurately. Three experiments examined the correspondence between motor decisions and affordances as participants reached through apertures of varying size. A psychophysical…

  17. SunShot Initiative: Making Solar Energy Affordable for All Americans (Fact Sheet)

    SciTech Connect

    Not Available

    2013-10-01

    Through SunShot, DOE supports efforts by private companies, universities, and national laboratories to drive down the cost of solar electricity to $0.06 per kilowatt-hour, making solar energy affordable for more American families and businesses.

  18. Traction sheave elevator, hoisting unit and machine space

    DOEpatents

    Hakala, Harri; Mustalahti, Jorma; Aulanko, Esko

    2000-01-01

    Traction sheave elevator consisting of an elevator car moving along elevator guide rails, a counterweight moving along counterweight guide rails, a set of hoisting ropes (3) on which the elevator car and counterweight are suspended, and a drive machine unit (6) driving a traction sheave (7) acting on the hoisting ropes (3) and placed in the elevator shaft. The drive machine unit (6) is of a flat construction. A wall of the elevator shaft is provided with a machine space with its open side facing towards the shaft, the essential parts of the drive machine unit (6) being placed in the space. The hoisting unit (9) of the traction sheave elevator consists of a substantially discoidal drive machine unit (6) and an instrument panel (8) mounted on the frame (20) of the hoisting unit.

  19. A magnetic emergency release system for halo traction.

    PubMed

    Augsburger, Sam; White, Hank; Iwinski, Henry; Tylkowski, Chester M

    2010-01-01

    A magnetic emergency release system was developed for use in halo traction systems. Commercially available rare earth mounting magnets, with selected weight-carrying capacities, along with ferromagnetic receptacles, were used in line between halos and overhead pulleys to both carry the prescribed traction force and provide an emergency release in the event of excessive applied force due to a transportation accident and/or sudden application of full body weight when using overhead walkers equipped with traction systems. The magnet-receptacle pairs were calibrated with an in-line digital scale. Load rate dependencies were noted, indicating that prescribed magnet-receptacle pairs should be chosen to carry at least 110% body weight. This weight capacity is reduced to approximately 88% of body weight during higher loading rates, such as transportation accidents and accidental falls.

  20. Constrained fatigue life optimization of a NASVYTIS multiroller traction drive

    NASA Technical Reports Server (NTRS)

    Coy, J. J.; Rohn, D. A.; Loewenthal, S. H.

    1980-01-01

    A contact fatigue life analysis method for multiroller traction drives is presented. The method is based on the Lundberg-Palmgren analysis method for rolling element bearing life prediction, and also uses life adjustment factors for materials, processing, lubrication, and effect of traction. The analysis method is applied in an optimization study to the multiroller traction drive, consisting of a single-stage planetary configuration with two rows of stepped planet rollers of five rollers per row. The drive was approximately 25 centimeters in diameter by 11 centimeters long, having a nominal ratio of 15:1. The theoretically predicted drive life was 2510 hours at a nominal continuous power and speed of 74.6 kW (100 hp) and 75,000 rpm.

  1. Extraction methods in bovine obstetrics: comparison of the demanded energy and importance of calf and traction method in the variance of force and energy.

    PubMed

    Tsousis, G; Becker, M; Lüpke, M; Goblet, F; Heun, C; Seifert, H; Bollwein, H

    2011-02-01

    In a previous study we could demonstrate that in terms of the required forces alternate traction is preferable to simultaneous traction for the obstetrical delivery of calves. The aims of this study were to examine the required energies for delivery of calves and to compare the effects of the factors of calf and traction method on the forces and energies required for the delivery. In a biomechanical in vitro model 12 stillborn Holstein-Friesian calves were pulled through the pelvic specimen of a cow at a controlled speed using two electric motors. Traction was applied simultaneously (ST) to both legs or alternately (AT) to one leg at a time to advance it 10 cm (AT 10) or 5 cm (AT5). Energies on each limb were measured digitally using load cells. The lowest energy for the entrance of the elbows in the pelvis was necessary using AT10 (19.9 ± 7.2 kJ, P < 0.05). In contrast, for the entrance of the chest, AT10 (104.9 ± 24.7 kJ) demanded 9% (P < 0.01) and 16% (P < 0.001) more energy than AT5 (96.7 ± 21.0 kJ) and ST (90.5 ± 24.9 kJ), respectively. Simultaneous traction tended to be better than AT5 (P = 0.09). Variance component estimates revealed that the factor calf contributed the main effect to the emerging forces and required energy. The traction method was responsible for up to 13% of the variance in most of the cases, but it accounted for 42% of the variance regarding the forces on the lower limb as the chest entered the pelvis. Based on these findings, the decision of the clinician whether or not to perform a manual traction should depend mainly on the calf. However, when such a decision has been made, alternate limb traction, 10 cm at a time, should be used until both elbows have entered the pelvis and a simultaneous traction should then be applied to complete extraction of the chest.

  2. [Research progress of endoscopic submucosal dissection with traction].

    PubMed

    Wu, Wenming; Wei, Zhi; Sun, Ziqin

    2016-01-01

    Endoscopic submucosal dissection (ESD) is a widely accepted treatment for early gastrointestinal cancer. However, the steep learning curve of standard ESD procedures makes it less widely applied in clinical practice. Therefore, various traction devices and techniques have been applied previously to facilitate ESD, such as clip-with-line method, Spring-assisted method, S-O clip method, magnetic anchor method, and robot-assisted method. These methods create a clear field of vision and allow dissections to be performed more quickly and safely. In this article, we will discuss various techniques for achieving tractions during ESD on clinical decision, and their advantages and disadvantages. PMID:26797847

  3. Evaluation of a high performance fixed-ratio traction drive

    NASA Technical Reports Server (NTRS)

    Loewenthal, S. H.; Anderson, N. E.; Rohn, D. A.

    1980-01-01

    The results of a test program to evaluate a compact, high performance, fixed ratio traction drive are presented. This transmission, the Nasvytis Multiroller Traction Drive, is a fixed ratio, single stage planetary with two rows of stepped planet rollers. Two versions of the drive were parametrically tested back-to-back at speeds to 73,000 rpm and power levels to 180 kW (240 hp). Parametric tests were also conducted with the Nasvytis drive retrofitted to an automotive gas turbine engine. The drives exhibited good performance, with a nominal peak efficiency of 94 to 96 percent and a maximum speed loss due to creep of approximately 3.5 percent.

  4. Traction-drive force transmission for telerobotic joints

    NASA Technical Reports Server (NTRS)

    Williams, D. M.; Kuban, D. P.

    1989-01-01

    A mechanism which meets the requirements of a teleoperated manipulator and those of an autonomous robot is discussed. The mechanism is a traction-drive differential that uses variable preload mechanisms. The differential provides compact design, with dextrous motion range and torque density similar to geared systems. The traction drive offers high stiffness to backlash for good robotic performance. The variable-loading mechanism (VLM) minimizes the drive-train friction for improved teleoperation. This combination provides a mechanism to allow advanced manipulation with either teleoperated control or autonomous robotic operation. The design principles of both major components of the joint mechanism are described.

  5. 21 CFR 888.5850 - Nonpowered orthopedic traction apparatus and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Nonpowered orthopedic traction apparatus and accessories. 888.5850 Section 888.5850 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... orthopedic traction apparatus and accessories. (a) Identification. A nonpowered orthopedic traction...

  6. 21 CFR 888.5850 - Nonpowered orthopedic traction apparatus and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nonpowered orthopedic traction apparatus and accessories. 888.5850 Section 888.5850 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... orthopedic traction apparatus and accessories. (a) Identification. A nonpowered orthopedic traction...

  7. Traction prediction of a smooth rigid wheel in soil using coupled eulerian-lagrangian analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Traction is an important performance requirement for a tire and is the force that propels a vehicle forward. Accurate traction prediction is important in reducing development cycle time and improving mechanistic understanding of tire traction performance. On a rigid surface like a paved road, trac...

  8. Affordable In-Space Transportation

    NASA Technical Reports Server (NTRS)

    Curtis, L. A.; VanDyke, M. K.; Lajoie, R. M.; Woodcock, G. R.

    1996-01-01

    Current and proposed launch systems will provide access to low-Earth orbit (LEO), and destinations beyond LEO, but the cost of delivering payloads will preclude the use of these services by many users. To develop and encourage revolutionary commercial utilization of geosynchronous orbit (GEO) and to provide an affordable means to continue NASA space science and exploration missions, the transportation costs to in-space destinations must be reduced. The principal objective of this study was to conceptually define three to four promising approaches to in-space transportation for delivery of satellites and other payloads, 3,000- to 10,000-lb class, to GEO destinations. This study established a methodology for evaluating in-space transportation systems based on life-cycle cost. The reusable concepts seemed to fare better in the evaluation than expendable, since a major driver in the life-cycle cost was the stage production cost.

  9. Modeling cell-matrix traction forces in Keratinocyte colonies

    NASA Astrophysics Data System (ADS)

    Banerjee, Shiladitya

    2013-03-01

    Crosstalk between cell-cell and cell-matrix adhesions plays an essential role in the mechanical function of tissues. The traction forces exerted by cohesive keratinocyte colonies with strong cell-cell adhesions are mostly concentrated at the colony periphery. In contrast, for weak cadherin-based intercellular adhesions, individual cells in a colony interact with their matrix independently, with a disorganized distribution of traction forces extending throughout the colony. In this talk I will present a minimal physical model of the colony as contractile elastic media linked by springs and coupled to an elastic substrate. The model captures the spatial distribution of traction forces seen in experiments. For cell colonies with strong cell-cell adhesions, the total traction force of the colony measured in experiments is found to scale with the colony's geometrical size. This scaling suggests the emergence of an effective surface tension of magnitude comparable to that measured for non-adherent, three-dimensional cell aggregates. The physical model supports the scaling and indicates that the surface tension may be controlled by acto-myosin contractility. Supported by the NSF through grant DMR-1004789. This work was done in collaboration with Aaron F. Mertz, Eric R. Dufresne and Valerie Horsley (Yale University) and M. Cristina Marchetti (Syracuse University).

  10. Animal Traction. Appropriate Technologies for Development. Manual M-12.

    ERIC Educational Resources Information Center

    Watson, Peter R.

    This manual is designed for use by Peace Corps volunteers and agricultural extension personnel working in animal traction development programs. While some of the information contained in the manual is specific to the extension of animal-powered agriculture in Africa, the principles covered are generally applicable wherever the method is being used…

  11. Group's "65 Percent Solution" Gains Traction, GOP Friends

    ERIC Educational Resources Information Center

    Hoff, David J.

    2005-01-01

    An effort to require school districts to funnel 65 percent of their budgets directly into classrooms is gaining traction in several states. Governor Rick Perry of Texas signed an executive order in August mandating that school districts implement the 65 Percent Solution, as the idea is called by the nonprofit group organizing the effort. It also…

  12. Candidate Coatings and Dry Traction Drives for Planetary Vehicles

    NASA Technical Reports Server (NTRS)

    Fusaro, Robert; Oswald, Fred B.

    2002-01-01

    Robert Fusaro and Fred Oswald of the Mechanical Components Branch discussed 'Candidate Coatings and Dry Traction Drives for Planetary Vehicles'. Vehicles to be designed for exploration of planets and moons of the solar system will require reliable mechanical drives to operate efficiently. Long-term operation of these drives will be challenging because of extreme operating conditions. These extreme conditions include: very high and/or very cold temperatures, wide temperature ranges, dust, vacuum or low-pressure atmospheres, and corrosive environments. Most drives used on Earth involve oil-lubricated gears. However, due to the extreme conditions on planetary surfaces, it may not be advisable or even possible to use oil lubrication. Unfortunately, solid lubricants do not work well when applied to gears because of the high contact stress conditions and large sliding motion between the teeth, which cause wear and limit life. We believe traction drives will provide an attractive alternative to gear drives. Traction drives are composed of rollers that provide geometry more conducive to solid lubrication. Minimal slip occurs in this contact geometry and thus there is very low wear to the solid lubricant. The challenge for these solid-lubricated drives is finding materials or coatings that provide the required long-life while also providing high traction. We seek materials that provide low wear with high friction.

  13. The use of extra-oral traction with removable appliances.

    PubMed

    Rock, W P

    1990-05-19

    Extra-oral traction has two main applications in orthodontic treatment. It may be used to prevent forward movement of anchor teeth and also to provide a force for distalisation of molars, and/or buccal segments. If correctly applied, EOT can help to ease problems in a difficult treatment and make possible an otherwise impossible treatment plan.

  14. Traction force dynamics predict gap formation in activated endothelium.

    PubMed

    Valent, Erik T; van Nieuw Amerongen, Geerten P; van Hinsbergh, Victor W M; Hordijk, Peter L

    2016-09-10

    In many pathological conditions the endothelium becomes activated and dysfunctional, resulting in hyperpermeability and plasma leakage. No specific therapies are available yet to control endothelial barrier function, which is regulated by inter-endothelial junctions and the generation of acto-myosin-based contractile forces in the context of cell-cell and cell-matrix interactions. However, the spatiotemporal distribution and stimulus-induced reorganization of these integral forces remain largely unknown. Traction force microscopy of human endothelial monolayers was used to visualize contractile forces in resting cells and during thrombin-induced hyperpermeability. Simultaneously, information about endothelial monolayer integrity, adherens junctions and cytoskeletal proteins (F-actin) were captured. This revealed a heterogeneous distribution of traction forces, with nuclear areas showing lower and cell-cell junctions higher traction forces than the whole-monolayer average. Moreover, junctional forces were asymmetrically distributed among neighboring cells. Force vector orientation analysis showed a good correlation with the alignment of F-actin and revealed contractile forces in newly formed filopodia and lamellipodia-like protrusions within the monolayer. Finally, unstable areas, showing high force fluctuations within the monolayer were prone to form inter-endothelial gaps upon stimulation with thrombin. To conclude, contractile traction forces are heterogeneously distributed within endothelial monolayers and force instability, rather than force magnitude, predicts the stimulus-induced formation of intercellular gaps. PMID:27498166

  15. On the non-singular traction-BIE in elasticity

    NASA Astrophysics Data System (ADS)

    Huang, Q.; Cruse, T. A.

    1994-06-01

    The work reported herein develops a generalized traction-boundary integral equations (BIE) formulation which involves only weakly singular integrals (in the three-dimensional problem) or totally regular integrals (in the two-dimensional problem). The first step deals with the terms in the Somigliana displacement identity, and then the derivatives of these terms. The only conditions required for the existence of the traction-BIE and the related Somigliana stress identity are weak continuity of the in-plane derivatives of the surface displacements and of the surface tractions. It is shown that the Cauchy principal value (CPV) interpretations so commonly used in BIE developments are unnecessary. The formulation is established not only at a smooth boundary point, but also at a corner point. The extension of the nonsingular formulation to discontinuous boundary tractions and tangential derivatives of the boundary displacements applicable to a generalized problem statement as well as the usual BEM implementations is also shown. In the demonstrated formulation, the source points are located directly at the boundary nodes and nonconformal elements are not needed.

  16. The activated face-bow: simple, safe, extraoral traction.

    PubMed

    Magni, F

    1979-02-01

    A simple and safe extraoral traction model is described. This consists of a face-bow with activated outer arms and a neck strap or headgear without any elastic force, such as rubber bands, elastic ribbons, coil springs, etc. The appliance cannot be withdrawn from the mouth by acident; therefore, the patient is protected from possible injuries.

  17. 21 CFR 890.5900 - Power traction equipment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Power traction equipment. 890.5900 Section 890.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5900 Power...

  18. 21 CFR 890.5900 - Power traction equipment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Power traction equipment. 890.5900 Section 890.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5900 Power...

  19. 21 CFR 890.5900 - Power traction equipment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Power traction equipment. 890.5900 Section 890.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5900 Power...

  20. 21 CFR 890.5900 - Power traction equipment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Power traction equipment. 890.5900 Section 890.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5900 Power...

  1. 21 CFR 890.5900 - Power traction equipment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Power traction equipment. 890.5900 Section 890.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5900 Power...

  2. New tool for applying traction during open reduction and internal fixation of acetabular fractures.

    PubMed

    Lien, Fang-Chieh

    2012-04-01

    Open reduction and internal fixation is used to treat complex acetabular fractures. Traction on the femur is necessary to reduce the acetabulum and is accomplished by surgical assistants or with mechanical devices. To overcome the disadvantages of various traction methods, the author designed a simple, novel traction device that can be used on an ordinary orthopedic or radiolucent operating table and has advantages over manual traction and commercial traction tables. The device consists of a horizontal cross-bar supported over the patient by 2 free-standing legs and is constructed from commercially available parts.

  3. 77 FR 56910 - Iowa Traction Railway Company-Acquisition and Operation Exemption-Rail Line of Iowa Traction...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-14

    ... milepost 10.4 at Clear Lake in Cerro Gordo County, Iowa (the Line). Iowa Railway states that the... in Control Exemption--Iowa Traction Ry., Docket No. FD 35671. The transaction may be consummated on... under 49 U.S.C. 10502(d) may be filed at any time. The filing of a petition to revoke will...

  4. Dopamine, affordance and active inference.

    PubMed

    Friston, Karl J; Shiner, Tamara; FitzGerald, Thomas; Galea, Joseph M; Adams, Rick; Brown, Harriet; Dolan, Raymond J; Moran, Rosalyn; Stephan, Klaas Enno; Bestmann, Sven

    2012-01-01

    The role of dopamine in behaviour and decision-making is often cast in terms of reinforcement learning and optimal decision theory. Here, we present an alternative view that frames the physiology of dopamine in terms of Bayes-optimal behaviour. In this account, dopamine controls the precision or salience of (external or internal) cues that engender action. In other words, dopamine balances bottom-up sensory information and top-down prior beliefs when making hierarchical inferences (predictions) about cues that have affordance. In this paper, we focus on the consequences of changing tonic levels of dopamine firing using simulations of cued sequential movements. Crucially, the predictions driving movements are based upon a hierarchical generative model that infers the context in which movements are made. This means that we can confuse agents by changing the context (order) in which cues are presented. These simulations provide a (Bayes-optimal) model of contextual uncertainty and set switching that can be quantified in terms of behavioural and electrophysiological responses. Furthermore, one can simulate dopaminergic lesions (by changing the precision of prediction errors) to produce pathological behaviours that are reminiscent of those seen in neurological disorders such as Parkinson's disease. We use these simulations to demonstrate how a single functional role for dopamine at the synaptic level can manifest in different ways at the behavioural level.

  5. College Affordability: Implications for College Opportunity

    ERIC Educational Resources Information Center

    Perna, Laura W.; Li, Chunyan

    2006-01-01

    By examining trends in college affordability, this article explores the extent to which the public perception that college is not affordable is justified. First, the article describes trends in national indicators that contribute to ability to pay, including income growth, health care costs, debt burden, and personal savings rates. Trends in…

  6. Affordability Funding Models for Early Childhood Services

    ERIC Educational Resources Information Center

    Purcal, Christiane; Fisher, Karen

    2006-01-01

    This paper presents a model of the approaches open to government to ensure that early childhood services are affordable to families. We derived the model from a comparative literature review of affordability approaches taken by government, both in Australia and internationally. The model adds significantly to the literature by proposing a means to…

  7. Affordability Approaches for Human Space Exploration

    NASA Technical Reports Server (NTRS)

    Holladay, Jon; Smith, David Alan

    2012-01-01

    The design and development of historical NASA Programs (Apollo, Shuttle and International Space Station), have been based on pre-agreed missions which included specific pre-defined destinations (e.g., the Moon and low Earth orbit). Due to more constrained budget profiles, and the desire to have a more flexible architecture for Mission capture as it is affordable, NASA is working toward a set of Programs that are capability based, rather than mission and/or destination specific. This means designing for a performance capability that can be applied to a specific human exploration mission/destination later (sometime years later). This approach does support developing systems to flatter budgets over time, however, it also poses the challenge of how to accomplish this effectively while maintaining a trained workforce, extensive manufacturing, test and launch facilities, and ensuring mission success ranging from Low Earth Orbit to asteroid destinations. NASA Marshall Space Flight Center (MSFC) in support of Exploration Systems Directorate (ESD) in Washington, DC has been developing approaches to track affordability across multiple Programs. The first step is to ensure a common definition of affordability: the discipline to bear cost in meeting a budget with margin over the life of the program. The second step is to infuse responsibility and accountability for affordability into all levels of the implementing organization since affordability is no single person s job; it is everyone s job. The third step is to use existing data to identify common affordability elements organized by configuration (vehicle/facility), cost, schedule, and risk. The fourth step is to analyze and trend this affordability data using an affordability dashboard to provide status, measures, and trends for ESD and Program level of affordability tracking. This paper will provide examples of how regular application of this approach supports affordable and therefore sustainable human space exploration

  8. Systematic traction techniques in minimal-access pediatric cardiac surgery.

    PubMed

    Oiwa, Hiroshi; Ishida, Ryoichi; Sudo, Kenichi

    2004-11-01

    Minimal-access pediatric cardiac surgery is now common in the treatment of simple congenital heart defects. However, methods of securing a good, unobstructed view for surgery and the difficulties of working in a deep, narrow field jeopardize safety in surgical procedures, especially for less experienced surgeons have been described. Our systematic, step-by-step traction techniques on the skin, the pericardium, the right atrial appendage, the aortic root, both venae cavae, and the free wall of the right ventricular outflow, using a mechanical retractor and traction sutures, facilitate surgical field exposure and the achievement of safety. As described below, our procedures are simple, allow direct inspection, and assist those working toward technical mastery.

  9. Traction drive automatic transmission for gas turbine engine driveline

    DOEpatents

    Carriere, Donald L.

    1984-01-01

    A transaxle driveline for a wheeled vehicle has a high speed turbine engine and a torque splitting gearset that includes a traction drive unit and a torque converter on a common axis transversely arranged with respect to the longitudinal centerline of the vehicle. The drive wheels of the vehicle are mounted on a shaft parallel to the turbine shaft and carry a final drive gearset for driving the axle shafts. A second embodiment of the final drive gearing produces an overdrive ratio between the output of the first gearset and the axle shafts. A continuously variable range of speed ratios is produced by varying the position of the drive rollers of the traction unit. After starting the vehicle from rest, the transmission is set for operation in the high speed range by engaging a first lockup clutch that joins the torque converter impeller to the turbine for operation as a hydraulic coupling.

  10. Traction radiographs in the diagnosis of chronic wrist pain.

    PubMed

    Fortems, Y; Mawhinney, I; Lawrence, T; Stanley, J K

    1994-06-01

    A sensitive non-invasive diagnostic test for intrinsic ligament rupture in patients with chronic wrist pain has still to be found. Differential displacement of the scaphoid, lunate and triquetrum can in some instances be seen during arthroscopy of acute wrist injuries and also on overdistraction of distal radial fractures with an external fixator. We performed a prospective study on 20 patients with chronic wrist pain using 2 kg and 5 kg traction radiographs without and with the addition of an ischaemic block, to assess differential displacement as a diagnostic criterion for intrinsic ligament rupture. Arthroscopy was used as arbiter of diagnosis. The sensitivity ranged from 14% to 57% and the specificity ranged from 53.7% to 100% according to the amount of traction and ischaemic block. In view of these poor results we conclude the stretch test has no additional value in the preoperative assessment of chronic wrist pain. PMID:8077822

  11. Thermal traction contact performance evaluation under fully flooded and starved conditions

    NASA Technical Reports Server (NTRS)

    Tevaarwerk, J. L.

    1985-01-01

    Ultra high speed traction tests were performed on two traction fluids commonly employed. Traction data on these fluids is required for purposes of traction drive design optimization techniques. To obtain the traction data, an existing twin disc traction test machine was employed. This machine was modified to accommodate the range of test variables. All the data reported was obtained under conditions of side slip, a technique whereby only low power levels are required to simulate real traction drive contacts. Theoretical traction predictions were performed for a representative number of curves that showed the influence of rolling velocity, of contact pressure and of aspect ratio. To establish the accuracy of the thermal model the predictions were performed ith increasing levels of independence of experimentally determined parameters. In the final resulting prediction only two non linear thermal parameters were used for the prediction of 15 different traction curves covering the entire range of variables as used in the investigation, with the exception of the influence of asperity traction. Comparison of these theoretical curves and corresponding experimental traces show very good agreement.

  12. The measurement, modeling, and prediction of traction for rocket propellant 1

    NASA Technical Reports Server (NTRS)

    Tevaarwerk, J. L.

    1989-01-01

    Traction tests were performed on RP-1, a common kerosene based rocket propellant. Traction data on this fluid are required for purposes of turbopump bearing design, using codes such as SHABERTH. To obtain the traction data, an existing twin disc machine was used, operating under the side slip mode and using elliptical contacts. The range of test variables were: contact peak Hertz stress from 1.0 to 2.0 GPa, disc surface speed from 10 to 50 m/s, fluid inlet temperature from 30 to 70 C, and with a contact aspect ratio of 1.7. The resulting traction curves were reduced to fundamental fluid property parameters using the Johnson and Tevaarwerk traction model. Theoretical traction predictions were performed by back substitution of the fundamental properties into the traction model. Comparison of the predicted with the measured curves gives a high degree of confidence in the correctness of the traction model. For purposes of input to the NASA SHABERTH program, the traction model was next used to predict the expected traction of RP-1 under line contact conditions.

  13. Traction force and tension fluctuations in growing axons

    PubMed Central

    Polackwich, Robert J.; Koch, Daniel; McAllister, Ryan; Geller, Herbert M.; Urbach, Jeffrey S.

    2015-01-01

    Actively generated mechanical forces play a central role in axon growth and guidance, but the mechanisms that underly force generation and regulation in growing axons remain poorly understood. We report measurements of the dynamics of traction stresses from growth cones of actively advancing axons from postnatal rat DRG neurons. By tracking the movement of the growth cone and analyzing the traction stress field from a reference frame that moves with it, we are able to show that there is a clear and consistent average stress field that underlies the complex spatial stresses present at any one time. The average stress field has strong maxima on the sides of the growth cone, directed inward toward the growth cone neck. This pattern represents a contractile stress contained within the growth cone, and a net force that is balanced by the axon tension. Using high time-resolution measurements of the growth cone traction stresses, we show that the stress field is composed of fluctuating local stress peaks, with a large number peaks that live for a short time, a population of peaks whose lifetime distribution follows an exponential decay, and a small number of very long-lived peaks. We show that the high time-resolution data also reveal that the tension appears to vary randomly over short time scales, roughly consistent with the lifetime of the stress peaks, suggesting that the tension fluctuations originate from stochastic adhesion dynamics. PMID:26578882

  14. Microglia mechanics: immune activation alters traction forces and durotaxis

    PubMed Central

    Bollmann, Lars; Koser, David E.; Shahapure, Rajesh; Gautier, Hélène O. B.; Holzapfel, Gerhard A.; Scarcelli, Giuliano; Gather, Malte C.; Ulbricht, Elke; Franze, Kristian

    2015-01-01

    Microglial cells are key players in the primary immune response of the central nervous system. They are highly active and motile cells that chemically and mechanically interact with their environment. While the impact of chemical signaling on microglia function has been studied in much detail, the current understanding of mechanical signaling is very limited. When cultured on compliant substrates, primary microglial cells adapted their spread area, morphology, and actin cytoskeleton to the stiffness of their environment. Traction force microscopy revealed that forces exerted by microglia increase with substrate stiffness until reaching a plateau at a shear modulus of ~5 kPa. When cultured on substrates incorporating stiffness gradients, microglia preferentially migrated toward stiffer regions, a process termed durotaxis. Lipopolysaccharide-induced immune-activation of microglia led to changes in traction forces, increased migration velocities and an amplification of durotaxis. We finally developed a mathematical model connecting traction forces with the durotactic behavior of migrating microglial cells. Our results demonstrate that microglia are susceptible to mechanical signals, which could be important during central nervous system development and pathologies. Stiffness gradients in tissue surrounding neural implants such as electrodes, for example, could mechanically attract microglial cells, thus facilitating foreign body reactions detrimental to electrode functioning. PMID:26441534

  15. Traction Forces of Endothelial Cells under Slow Shear Flow

    PubMed Central

    Perrault, Cecile M.; Brugues, Agusti; Bazellieres, Elsa; Ricco, Pierre; Lacroix, Damien; Trepat, Xavier

    2015-01-01

    Endothelial cells are constantly exposed to fluid shear stresses that regulate vascular morphogenesis, homeostasis, and disease. The mechanical responses of endothelial cells to relatively high shear flow such as that characteristic of arterial circulation has been extensively studied. Much less is known about the responses of endothelial cells to slow shear flow such as that characteristic of venous circulation, early angiogenesis, atherosclerosis, intracranial aneurysm, or interstitial flow. Here we used a novel, to our knowledge, microfluidic technique to measure traction forces exerted by confluent vascular endothelial cell monolayers under slow shear flow. We found that cells respond to flow with rapid and pronounced increases in traction forces and cell-cell stresses. These responses are reversible in time and do not involve reorientation of the cell body. Traction maps reveal that local cell responses to slow shear flow are highly heterogeneous in magnitude and sign. Our findings unveil a low-flow regime in which endothelial cell mechanics is acutely responsive to shear stress. PMID:26488643

  16. Microglia mechanics: immune activation alters traction forces and durotaxis.

    PubMed

    Bollmann, Lars; Koser, David E; Shahapure, Rajesh; Gautier, Hélène O B; Holzapfel, Gerhard A; Scarcelli, Giuliano; Gather, Malte C; Ulbricht, Elke; Franze, Kristian

    2015-01-01

    Microglial cells are key players in the primary immune response of the central nervous system. They are highly active and motile cells that chemically and mechanically interact with their environment. While the impact of chemical signaling on microglia function has been studied in much detail, the current understanding of mechanical signaling is very limited. When cultured on compliant substrates, primary microglial cells adapted their spread area, morphology, and actin cytoskeleton to the stiffness of their environment. Traction force microscopy revealed that forces exerted by microglia increase with substrate stiffness until reaching a plateau at a shear modulus of ~5 kPa. When cultured on substrates incorporating stiffness gradients, microglia preferentially migrated toward stiffer regions, a process termed durotaxis. Lipopolysaccharide-induced immune-activation of microglia led to changes in traction forces, increased migration velocities and an amplification of durotaxis. We finally developed a mathematical model connecting traction forces with the durotactic behavior of migrating microglial cells. Our results demonstrate that microglia are susceptible to mechanical signals, which could be important during central nervous system development and pathologies. Stiffness gradients in tissue surrounding neural implants such as electrodes, for example, could mechanically attract microglial cells, thus facilitating foreign body reactions detrimental to electrode functioning. PMID:26441534

  17. Enzymatic vitreolysis with recombinant tissue plasminogen activator for vitreomacular traction

    PubMed Central

    Raczyńska, Dorota; Lipowski, Paweł; Zorena, Katarzyna; Skorek, Andrzej; Glasner, Paulina

    2015-01-01

    Aims The aim of our research was to gain data about the efficacy of intravitreal injections of a recombinant tissue plasminogen activator (rTPA) in dissolving vitreoretinal tractions (VRTs). Materials and methods The study group consisted of patients of our Ophthalmology Clinic who had received an injection of rTPA (TPA Group) for an existent vitreomacular traction confirmed by optical coherence tomography and stereoscopic examinations. The control group consisted of patients who had declined treatment despite the existence of a vitreomacular traction confirmed by the same diagnostic methods. Each group consisted of 30 people (30 eyes). The observation period was 6 months. Conclusion In both groups some of the VRTs had dissolved. In the TPA group the traction dissolved in 10 patients (33.33%) and in the control group only in 5 (16.67%). It is also important to point out that the mean baseline membrane thickness was higher in the TPA group than in the control group. Observing patients in both groups we noticed that the dissolution of vitreoretinal membrane occurred most frequently in those cases where the membrane was thin. In the TPA group, the mean membrane thickness after 6 months decreased considerably. At the same time, no significant change in the membrane thickness could be observed in the control group. Observation of the retinal thickness allows us to draw the following conclusion: in the TPA group, the retinal thickness in the macular area (edema) had decreased over the study period, whereas in the control group it had increased. In those cases where the traction had dissolved, the edema of the retina decreased by the end of the 6-month period in both groups. In the TPA group, the dissolution of the membrane occurred most often within 3 months from the primary injection. Based on statistics, we can confirm that in the control group there was a decrease in visual acuity during the 6 months of the study period. At the same time, visual acuity in the TPA

  18. Scoliosis elasticity assessed by manual traction: 49 juvenile and adolescent idiopathic cases.

    PubMed

    Soucacos, P K; Soucacos, P N; Beris, A E

    1996-04-01

    We assessed preoperative curve elasticity in 49 consecutive patients with juvenile or adolescent idiopathic scoliosis who were operated on with Harrington distraction rods. Preoperatively, the curve was determined from posteroanterior radiographs taken in the standing position and in the supine position, with traction. In the latter, the radiographs were taken at the moment of maximal traction when one technician applied traction to the ankles and another to the wrists. The scoliotic curve in the 10 patients with juvenile scoliosis averaged 59 degrees and 32 degrees in the standing and supine positions with traction, respectively. Immediately postoperatively, the curve averaged 19 degrees. 39 patients with adolescent scoliosis had a scoliotic curve which averaged 58 degrees in the standing position and 32 degrees in the supine position with traction. The mean postoperative measurement was 21 degrees. These findings suggest that manual traction is a simple and reliable means of predicting the minimal correction of the scoliotic curve to be expected, using Harrington distraction rods.

  19. FY2011 Oak Ridge National Laboratory Annual Progress Report for the Power Electronics and Electric Machinery Program

    SciTech Connect

    Olszewski, Mitchell

    2011-10-01

    develop the appropriate technical targets for systems, subsystems, and component R&D activities; (2) develop and validate individual subsystems and components, including EMs and PE; and (3) determine how well the components and subsystems work together in a vehicle environment or as a complete propulsion system and whether the efficiency and performance targets at the vehicle level have been achieved. The research performed under this subprogram will help remove technical and cost barriers to enable the development of technology for use in such advanced vehicles as hybrid electric vehicles (HEVs), plug-in HEVs (PHEVs), battery electric vehicles, and fuel-cell-powered automobiles that meet the goals of the VTP. A key element in making these advanced vehicles practical is providing an affordable electric traction drive system. This will require attaining weight, volume, efficiency, and cost targets for the PE and EM subsystems of the traction drive system. Areas of development include: (1) novel traction motor designs that result in increased power density and lower cost; (2) inverter technologies involving new topologies to achieve higher efficiency with the ability to accommodate higher temperature environments while achieving high reliability; (3) converter concepts that use methods of reducing the component count and integrating functionality to decrease size, weight, and cost; (4) new onboard battery charging concepts that result in decreased cost and size; (5) more effective thermal control through innovative packaging technologies; and (6) integrated motor-inverter traction drive system concepts. ORNL's PEEM research program conducts fundamental research, evaluates hardware, and assists in the technical direction of the VTP Advanced Power Electronics and Electric Motors (APEEM) program. In this role, ORNL serves on the U.S. DRIVE Electrical and Electronics Technical Team, evaluates proposals for DOE, and lends its technological expertise to the direction of projects

  20. The influence of surface dents and grooves on traction in sliding EHD point contacts

    NASA Technical Reports Server (NTRS)

    Cusano, C.; Wedeven, L. D.

    1982-01-01

    Changes in traction, caused by dents and grooves on a highly polished ball,are investigated as these defects approach and go through sliding elastohydrodynamic point contacts. The contacts are formed with the ball loading against a transparent disk. The ball and thus the topographical features are held stationary at various locations in the vicinity and within the contact while the disk is rotating. These topographical features can cause substantial changes in the traction when compared to traction obtained with smooth surfaces.

  1. MISSE-X: Affordable Space Environment Testing

    NASA Video Gallery

    MISSE–X is a robotically serviceable ISS external facility providing government, industry and academia experimenters with affordable access to space for materials durability testing of potential ...

  2. Human small intestinal contractions and aboral traction forces during fasting and after feeding.

    PubMed Central

    Ahluwalia, N K; Thompson, D G; Barlow, J; Heggie, L

    1994-01-01

    Small intestinal intraluminal pressure activity and aboral traction forces were explored in 19 healthy volunteers using a combined manometry and traction force detecting assembly sited in the upper small intestine. Each aboral traction event was classified as being associated with either a propagating or a stationary contraction and its force measured. During phase I no contractions or traction events were seen. During phase II, traction events related to propagating contractions mean (SEM) (2.2 (0.2)/min) and to stationary contractions (0.3 (0.1)/min) generated similar force/event (7.5(0.9 g v 8.7 (1.4) g, p > 0.05). During phase III, all traction events were related to propagating contractions and generated 9.3 (2.4) g force/event (p > 0.05 v phase II). After feeding, traction events related to propagating contractions generated similar force/event to those related to stationary contractions (5.9 (1.0) g v 9.3 (2.7) g, p > 0.05 v each other and v fasting). No consistent pattern was seen in the temporal distribution of the traction events or in the pattern of the amplitude of the force of successive traction events. PMID:8200554

  3. Growth cone behavior and production of traction force

    PubMed Central

    1990-01-01

    The growth cone must push its substrate rearward via some traction force in order to propel itself forward. To determine which growth cone behaviors produce traction force, we observed chick sensory growth cones under conditions in which force production was accommodated by movement of obstacles in the environment, namely, neurites of other sensory neurons or glass fibers. The movements of these obstacles occurred via three, different, stereotyped growth cone behaviors: (a) filopodial contractions, (b) smooth rearward movement on the dorsal surface of the growth cone, and (c) interactions with ruffling lamellipodia. More than 70% of the obstacle movements were caused by filopodial contractions in which the obstacle attached at the extreme distal end of a filopodium and moved only as the filopodium changed its extension. Filopodial contractions were characterized by frequent changes of obstacle velocity and direction. Contraction of a single filopodium is estimated to exert 50-90 microdyn of force, which can account for the pull exerted by chick sensory growth cones. Importantly, all five cases of growth cones growing over the top of obstacle neurites (i.e., geometry that mimics the usual growth cone/substrate interaction), were of the filopodial contraction type. Some 25% of obstacle movements occurred by a smooth backward movement along the top surface of growth cones. Both the appearance and rate of movements were similar to that reported for retrograde flow of cortical actin near the dorsal growth cone surface. Although these retrograde flow movements also exerted enough force to account for growth cone pulling, we did not observe such movements on ventral growth cone surfaces. Occasionally obstacles were moved by interaction with ruffling lamellipodia. However, we obtained no evidence for attachment of the obstacles to ruffling lamellipodia or for directed obstacle movements by this mechanism. These data suggest that chick sensory growth cones move forward by

  4. Influences on lifetime of wire ropes in traction lifts

    NASA Astrophysics Data System (ADS)

    Vogel, W.

    2016-05-01

    Traction lifts are complex systems with rotating and translating moving masses, springs and dampers and several system inputs from the lifts and the users. The wire ropes are essential mechanical elements. The mechanical properties of the ropes in use depend on the rope construction, the load situation, nonlinearities and the lift dimensions. The mechanical properties are important for the proper use in lifts and the ride quality. But first of all the wire ropes (for all other suspension means as well) have to satisfy the safety relevant requirements sufficient lifetime, reliable determination of discard and sufficient and limited traction capacity. The lifetime of the wire ropes better the number of trips until rope discard depends on a lot of parameters of the rope and the rope application eg use of plastic deflection sheaves and reverse bending layouts. New challenges for rope lifetime are resulting from the more or less open D/d-ratio limits possible by certificates concerning the examination of conformity by notified bodies. This paper will highlight the basics of wire rope technology, the endurance and lifetime of wire ropes running over sheaves, and the different influences from the ropes and more and more important from the lift application parameters. Very often underestimated are the influences of transport, storage, installation and maintenance. With this background we will lead over to the calculation methods of wire rope lifetime considering the actual findings of wire rope endurance research. We'll show in this paper new and innovative facts as the influence of rope length and size factor in the lifetime formular, the reduction of lifetime caused by traction grooves, the new model for the calculation in reverse bending operations and the statistically firmed possibilities for machine roomless lifts (MRL) under very small bending conditions.

  5. Affordability of the Health Expenditures of Insured Americans Before the Affordable Care Act.

    PubMed

    Nyman, John A; Trenz, Helen M

    2016-02-01

    Central to the Affordable Care Act is the notion of affordability and the role of health insurance in making otherwise unaffordable health care affordable. We used data from the 1996 to 2008 versions of the Medical Expenditure Panel Survey to estimate the portion of overall health care expenditures by insured respondents that would otherwise have been beyond their disposable incomes and assets. We found that about one third of insured expenditures would have been unaffordable, with a much higher percentage among publicly insured individuals. This result suggests that one of the main functions of insurance is to cover expenses that insured individuals would not otherwise be able to afford. PMID:26691116

  6. Affordability of the Health Expenditures of Insured Americans Before the Affordable Care Act.

    PubMed

    Nyman, John A; Trenz, Helen M

    2016-02-01

    Central to the Affordable Care Act is the notion of affordability and the role of health insurance in making otherwise unaffordable health care affordable. We used data from the 1996 to 2008 versions of the Medical Expenditure Panel Survey to estimate the portion of overall health care expenditures by insured respondents that would otherwise have been beyond their disposable incomes and assets. We found that about one third of insured expenditures would have been unaffordable, with a much higher percentage among publicly insured individuals. This result suggests that one of the main functions of insurance is to cover expenses that insured individuals would not otherwise be able to afford.

  7. Affordable housing: Reducing the energy cost burden

    SciTech Connect

    Lee, A.D.; Chin, R.I.; Marden, C.L.

    1995-01-01

    Residential energy expenditures are a key determinant of housing affordability, particularly for lower Income households. For years, federal, state and local governments and agencies have sought to defray energy expenses and Increase residential energy efficiency for low Income households through legislative and regulatory actions and programs. Nevertheless, household energy costs continue to place a major burden on lower Income families. This issue paper was written to help formulate national energy policy by providing the United States Department of Energy`s (DOE`s) Office of Energy Efficiency and Renewable Energy (EE) with Information to help define the affordable housing issue; Identify major drivers, key factors, and primary stakeholders shaping the affordable housing issue; and review how responding to this Issue may impact EE`s goals and objectives and Influence the strategic direction of the office. Typically, housing affordability is an Issue associated with lower income households. This issue paper adopts this perspective, but it is important to note that reducing energy utility costs can make {open_quotes}better{close_quote} housing affordable to any household regardless of income. As energy efficiency is improved throughout all sectors of the economy, special consideration must be given to low income households. Of all households, low income households are burdened the most by residential energy costs; their residences often are the least energy-efficient and have the greatest potential for efficiency improvements, but the occupants have the fewest resources to dedicate to conservation measures. This paper begins with a definition of {open_quotes}affordability{close_quotes} as it pertains to total housing costs and summarizes several key statistics related to housing affordability and energy use by lower income households.

  8. Pseudo-Class III treatment with reverse traction: case report.

    PubMed

    dos Santos-Pinto, A; Paulin, R F; Melo, A C

    2001-01-01

    The pseudo-Class III can be defined as a functional reflex of an anterior positioning of the mandible, an acquired muscular position that simulates a mesiocclusion. The diagnosis and treatment plan of this condition must be based on a cephalometric evaluation that provides information about the relative contributions of the skeletal and dental components to the malocclusion. There is still great controversies about when is the best moment to start the Class III treatment. The purpose of this article is to describe a case report in which a Class III patient was successfully treated with reverse traction. PMID:11497006

  9. [The bionator with extraoral traction--the Wurzburg concept. 1].

    PubMed

    Witt, E; Sahm, G; Hevia, R

    1990-11-01

    In this publication the bionator with extraoral anterior traction is presented. The preparation of the bionator and the headgear fit is demonstrated. The indication for the use of the appliance combination is outlined. The results of a cephalometric study concerning the therapeutic effects are presented. The following changes are especially noteworthy: There is a reduction of the SNA-angle, a significant retrusion of the upper incisors occurs. The mesial drift of the upper 6-year molars is inhibited, a slight posterior rotation of the maxilla is observed. In patients who wore their appliances well, a protrusion of the lower incisors could not be observed.

  10. Traction studies of northeast corridor rail passenger service: Executive summary

    NASA Technical Reports Server (NTRS)

    Macie, T. W.; Stallkamp, J. A.

    1980-01-01

    The enabling legislation of 1976 for improvement of service in the Northeast corridor (NEC) requires a schedule of 2 h 40 min between Washington and New York City by 1981 and 3 h 40 min between NYC and Boston, when the electrification is completed. Various options of the NEC operation that may satisfy the legislation were investigated, particularly in terms of travel time and energy consumption. NEC operations were compared with overseas systems and practices. The emerging new technology of AC traction was also evaluated.

  11. FreedomCAR Advanced Traction Drive Motor Development Phase I

    SciTech Connect

    Ley, Josh; Lutz, Jon

    2006-09-01

    The overall objective of this program is to design and develop an advanced traction motor that will meet the FreedomCAR and Vehicle Technologies (FCVT) 2010 goals and the traction motor technical targets. The motor specifications are given in Section 1.3. Other goals of the program include providing a cost study to ensure the motor can be developed within the cost targets needed for the automotive industry. The program has focused on using materials that are both high performance and low costs such that the performance can be met and cost targets are achieved. In addition, the motor technologies and machine design features must be compatible with high volume manufacturing and able to provide high reliability, efficiency, and ruggedness while simultaneously reducing weight and volume. Weight and volume reduction will become a major factor in reducing cost, material cost being the most significant part of manufacturing cost at high volume. Many motor technology categories have been considered in the past and present for traction drive applications, including: brushed direct current (DC), PM (PM) brushless dc (BLDC), alternating current (AC) induction, switched reluctance and synchronous reluctance machines. Of these machine technologies, PM BLDC has consistently demonstrated an advantage in terms of power density and efficiency. As rare earth magnet cost has declined, total cost may also be reduced over the other technologies. Of the many different configurations of PM BLDC machines, those which incorporate power production utilizing both magnetic torque as well as reluctance torque appear to have the most promise for traction applications. There are many different PM BLDC machine configurations which employ both of these torque producing mechanisms; however, most would fall into one of two categories--some use weaker magnets and rely more heavily on reluctance torque (reluctance-dominant PM machines), others use strong PMs and supplement with reluctance torque

  12. Scientific Laboratory Platform for Testing the Electric Vehicle Equipped with DC Drive

    NASA Astrophysics Data System (ADS)

    Brazis, V.; Kroics, K.; Grigans, L.

    2014-12-01

    The authors present a test platform for the low-power DC electric motor of a traction vehicle or a high-power motor scaled in the traction and braking modes. The load emulator of the traction drive is made using an induction motor controlled by a frequency converter. A microcontroller controls the bi-directional DC/DC converter and sends a speed reference signal to the frequency converter. The test bench is meant for determination of the power consumption by motor in various speed cycles, and will be used to demonstrate the operation of electric vehicle to students and to investigate the charging/discharging strategies of energy sources.

  13. Preliminary evaluation of the Illinois Residential Affordable Payment Program (IRAPP)

    SciTech Connect

    Reddy, A.B.; Griffin, B.S.; Lieberman, B.; Baker, D.

    1988-03-01

    The Illinois Residential Affordable Payment Program (IRAPP) was authorized by the Illinois Energy Assistance Act of 1985. IRAPP is an energy-assistance program for low-income households that have incomes of less than 125% of poverty level and receive utility services from a public utility. In return for percent of income payments, low-income households are guaranteed continuous natural gas and/or electricity utility service. The program was placed in operation in December 1985. The study reported here is an evaluation of this program. Program-eligible households were compared to determine: (1) what household characteristics lead to program participation; (2) what effects the program has on consumption of natural gas and electricity, utility-service disconnections, and low-income households' utility costs; and (3) how much the program cost per participant household.

  14. Applications of Traction Force Microscopy in Measuring Adhesion Molecule Dependent Cell Contractility

    ERIC Educational Resources Information Center

    Mann, Cynthia Marie

    2009-01-01

    This work describes the use of polyacrylamide hydrogels as controlled elastic modulus substrates for single cell traction force microscopy studies. The first section describes the use of EDC/NHS chemistry to convalently link microbeads to the hydrogel matrix for the purpose of performing long-term traction force studies (7 days). The final study…

  15. Electric vehicle drive train with contactor protection

    DOEpatents

    Konrad, C.E.; Benson, R.A.

    1994-11-29

    A drive train for an electric vehicle includes a traction battery, a power drive circuit, a main contactor for connecting and disconnecting the traction battery and the power drive circuit, a voltage detector across contacts of the main contactor, and a controller for controlling the main contactor to prevent movement of its contacts to the closed position when the voltage across the contacts exceeds a predetermined threshold, to thereby protect the contacts of the contactor. The power drive circuit includes an electric traction motor and a DC-to-AC inverter with a capacitive input filter. The controller also inhibits the power drive circuit from driving the motor and thereby discharging the input capacitor if the contacts are inadvertently opened during motoring. A precharging contactor is controlled to charge the input filter capacitor prior to closing the main contactor to further protect the contacts of the main contactor. 3 figures.

  16. Electric vehicle drive train with contactor protection

    DOEpatents

    Konrad, Charles E.; Benson, Ralph A.

    1994-01-01

    A drive train for an electric vehicle includes a traction battery, a power drive circuit, a main contactor for connecting and disconnecting the traction battery and the power drive circuit, a voltage detector across contacts of the main contactor, and a controller for controlling the main contactor to prevent movement of its contacts to the closed position when the voltage across the contacts exceeds a predetermined threshold, to thereby protect the contacts of the contactor. The power drive circuit includes an electric traction motor and a DC-to-AC inverter with a capacitive input filter. The controller also inhibits the power drive circuit from driving the motor and thereby discharging the input capacitor if the contacts are inadvertently opened during motoring. A precharging contactor is controlled to charge the input filter capacitor prior to closing the main contactor to further protect the contacts of the main contactor.

  17. Periodic traction in migrating large amoeba of Physarum polycephalum.

    PubMed

    Rieu, Jean-Paul; Delanoë-Ayari, Hélène; Takagi, Seiji; Tanaka, Yoshimi; Nakagaki, Toshiyuki

    2015-05-01

    The slime mould Physarum polycephalum is a giant multinucleated cell exhibiting well-known Ca(2+)-dependent actomyosin contractions of its vein network driving the so-called cytoplasmic shuttle streaming. Its actomyosin network forms both a filamentous cortical layer and large fibrils. In order to understand the role of each structure in the locomotory activity, we performed birefringence observations and traction force microscopy on excised fragments of Physarum. After several hours, these microplasmodia adopt three main morphologies: flat motile amoeba, chain types with round contractile heads connected by tubes and motile hybrid types. Each type exhibits oscillations with a period of about 1.5 min of cell area, traction forces and fibril activity (retardance) when fibrils are present. The amoeboid types show only peripheral forces while the chain types present a never-reported force pattern with contractile rings far from the cell boundary under the spherical heads. Forces are mostly transmitted where the actomyosin cortical layer anchors to the substratum, but fibrils maintain highly invaginated structures and contribute to forces by increasing the length of the anchorage line. Microplasmodia are motile only when there is an asymmetry in the shape and/or the force distribution.

  18. Traction-drive force transmission for telerobotic joints

    NASA Technical Reports Server (NTRS)

    Kuban, D. P.; Williams, D. M.

    1989-01-01

    The U.S. Space Station Program is providing many technological developments to meet the increasing demands of designing such a facility. One of the key areas of research is that of telerobotics for space station assembly and maintenance. Initial implementation will be teleoperated, but long-term plans call for autonomous robotics. One of the essential components for making this transition successful is the manipulator joints mechanism. Historically, teleoperated manipulators and industrial robotics have had very different mechanisms for force transmission. This is because the design objectives are almost mutually exclusive. A teleoperator must have very low friction and inertia to minimize operator fatigue; backlash and stiffness are of secondary concern. A robot, however, must have minimum backlash, and high stiffness for accurate and rapid positioning. A joint mechanism has yet to be developed that can optimize these divergent performance objectives. A joint mechanism that approaches this optimal performance was developed for NASA Langley, Automation Technology Branch. It is a traction-drive differential that uses variable preload mechanisms. The differential provides compact, dexterous motion range with a torque density similar to geared systems. The traction drive offers high stiffness and zero backlash, for good robotic performance, and the variable loading mechanism (VLM) minimizes the drive-train friction, for improved teleoperation.

  19. Traction force and tension fluctuations in growing axons

    NASA Astrophysics Data System (ADS)

    Urbach, Jeffrey; Polackwich, Jamie; Koch, Daniel; McAllister, Ryan; Geller, Herbert

    Actively generated mechanical forces play a central role in axon growth and guidance during nervous system development. We describe the dynamics of traction stresses from growth cones of actively advancing axons from postnatal rat DRG neurons. By tracking the movement of the growth cone and analyzing the traction stresses in a co-moving reference frame, we show that there is a clear and consistent average stress field underlying the complex spatial stresses present at any one time. The average stress field has strong maxima on the sides of the growth cone, directed inward toward the growth cone neck. This pattern represents a Contractile stress contained within the growth cone, and a net force that is balanced by the axon tension. In addition, using high time-resolution measurements, we show that the stress field is composed of fluctuating local stress peaks, with a population of peaks whose lifetime distribution follows an exponential decay, and a small number of very long-lived peaks. We also find that the tension appears to vary randomly over short time scales, roughly consistent with the lifetime of the stress peaks, suggesting that the tension fluctuations originate from stochastic adhesion dynamics.

  20. Periodic traction in migrating large amoeba of Physarum polycephalum

    PubMed Central

    Rieu, Jean-Paul; Delanoë-Ayari, Hélène; Takagi, Seiji; Tanaka, Yoshimi; Nakagaki, Toshiyuki

    2015-01-01

    The slime mould Physarum polycephalum is a giant multinucleated cell exhibiting well-known Ca2+-dependent actomyosin contractions of its vein network driving the so-called cytoplasmic shuttle streaming. Its actomyosin network forms both a filamentous cortical layer and large fibrils. In order to understand the role of each structure in the locomotory activity, we performed birefringence observations and traction force microscopy on excised fragments of Physarum. After several hours, these microplasmodia adopt three main morphologies: flat motile amoeba, chain types with round contractile heads connected by tubes and motile hybrid types. Each type exhibits oscillations with a period of about 1.5 min of cell area, traction forces and fibril activity (retardance) when fibrils are present. The amoeboid types show only peripheral forces while the chain types present a never-reported force pattern with contractile rings far from the cell boundary under the spherical heads. Forces are mostly transmitted where the actomyosin cortical layer anchors to the substratum, but fibrils maintain highly invaginated structures and contribute to forces by increasing the length of the anchorage line. Microplasmodia are motile only when there is an asymmetry in the shape and/or the force distribution. PMID:25808339

  1. Achieving Sustainable Construction in Affordable Housing

    SciTech Connect

    Barcik, M.K.; Creech, D.B.; Ternes, M.P.

    1998-12-07

    An energy-efficient design and construction checklist and information sheets on energy-efficient design and construction are two products being developed. These products will help affordable housing providers take the first steps toward a whole-house approach to the design and implementation of energy-efficient construction practices. The checklist presents simple and clear guidance on energy improvements that can be readily addressed now by most affordable housing providers. The information sheets complement the checklist by providing installation instructions and material specifications that are accompanied by detailed graphics. The information sheets also identify benefits of recommended energy-efficiency measures and procedures including cost savings and impacts on health and comfort. This paper presents details on the checklist and information sheets and discusses their use in two affordable housing projects.

  2. The Transformation of Ergonomic Affordances into Cultural Affordances: The Case of the Alnuset System

    ERIC Educational Resources Information Center

    Chiappini, Giampaolo

    2012-01-01

    Is it possible to study the ergonomic affordances offered by a system designed for educational aims and their transformation into cultural affordances? To this purpose, what references can we adopt? This work describes the theoretical framework used to realise this study referring to AlNuSet, a system realised within the EC ReMath project to…

  3. Limb apraxia and the "affordance competition hypothesis".

    PubMed

    Rounis, Elisabeth; Humphreys, Glyn

    2015-01-01

    Limb apraxia, a disorder of higher order motor control, has long been a challenge for clinical assessment and understanding (Leiguarda and Marsden, 2000). The deficits originally described in limb apraxia (Liepmann, 1920) have been classified by the nature of the errors made by the patients leading to, namely, ideational and ideomotor apraxia. The dual stream hypothesis (Goodale and Milner, 1992) has been used to explain these categories: ideational apraxia is thought to relate to a deficit in the concept of a movement (coded in the ventral stream). Patients have difficulty using objects, sequencing actions to interact with them or pantomiming their use. Ideomotor apraxia, on the other hand, is thought to arise from problems in the accurate implementation of movements within the dorsal stream. One of the limitations on understanding apraxia is the failure by the clinical literature to draw on knowledge of the factors determining actions in the environment. Here we emphasize the role of affordance. There is much recent work indicating that our responses to stimuli are strongly influenced by the actions that the objects "afford", based on their physical properties and the intentions of the actor (e.g., Tucker and Ellis, 1998). The concept of affordance, originally suggested by Gibson (1979) has been incorporated in a recent model of interactive behavior that draws from findings in non-human primates, namely the "affordance competition hypothesis" (Cisek, 2007). This postulates that interactive behavior arises by a process of competition between possible actions elicited by the environment. In this paper we argue that "affordance competition" may play a role in apraxia. We review evidence that at least some aspects of apraxia may reflect an abnormal sensitivity to competition when multiple affordances are present (Riddoch et al., 1998) and/or a poor ability to exert cognitive control over this competition when it occurs. This framework suggests a new way of

  4. The Study on Tribological Characteristic of Traction Drives In Non-steady Condition

    NASA Astrophysics Data System (ADS)

    Tozaki, Yasuyoshi; Hayashi, Noriyuki; Matsumoto, Susumu

    The purpose of this study is to investigate the effect on oil film thickness and traction coefficient by the sudden change of loaded torque on traction drives. The experimental measurements of oil film thickness and traction force were performed using the optical interferometic observation method. And the comparison of experimental results with calculations of the two dimensional non-steady thermal elastohydrodynamic lubrication (TEHL) was performed. We obtained that oil film thickness and traction coefficient decrease though the rotating speed of roller and disc increase, and our discussion lead that the reason of the decrease is the effect of the increase of oil film temperature by shear. The consideration of frictional heating improved the accuracy of calculations about oil film thickness and traction coefficient.

  5. Affordance Templates for Shared Robot Control

    NASA Technical Reports Server (NTRS)

    Hart, Stephen; Dinh, Paul; Hambuchen, Kim

    2014-01-01

    This paper introduces the Affordance Template framework used to supervise task behaviors on the NASA-JSC Valkyrie robot at the 2013 DARPA Robotics Challenge (DRC) Trials. This framework provides graphical interfaces to human supervisors that are adjustable based on the run-time environmental context (e.g., size, location, and shape of objects that the robot must interact with, etc.). Additional improvements, described below, inject degrees of autonomy into instantiations of affordance templates at run-time in order to enable efficient human supervision of the robot for accomplishing tasks.

  6. Learning to grasp and extract affordances: the Integrated Learning of Grasps and Affordances (ILGA) model.

    PubMed

    Bonaiuto, James; Arbib, Michael A

    2015-12-01

    The activity of certain parietal neurons has been interpreted as encoding affordances (directly perceivable opportunities) for grasping. Separate computational models have been developed for infant grasp learning and affordance learning, but no single model has yet combined these processes in a neurobiologically plausible way. We present the Integrated Learning of Grasps and Affordances (ILGA) model that simultaneously learns grasp affordances from visual object features and motor parameters for planning grasps using trial-and-error reinforcement learning. As in the Infant Learning to Grasp Model, we model a stage of infant development prior to the onset of sophisticated visual processing of hand-object relations, but we assume that certain premotor neurons activate neural populations in primary motor cortex that synergistically control different combinations of fingers. The ILGA model is able to extract affordance representations from visual object features, learn motor parameters for generating stable grasps, and generalize its learned representations to novel objects.

  7. 77 FR 61049 - Iowa Traction Railway Company-Change in Operators Exemption-Rail Line of Backtrack, Inc.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-05

    ... Surface Transportation Board Iowa Traction Railway Company--Change in Operators Exemption-- Rail Line of Backtrack, Inc. Iowa Traction Railway Company (Iowa Railway) \\1\\ has filed a verified notice of exemption under 49 CFR 1150.31 to change operators from Iowa Traction Railroad Company (Iowa Railroad) to...

  8. Electrical and Electronics Technical Team Roadmap

    SciTech Connect

    2013-06-01

    The Electrical and Electronics Technical Team’s (EETT's) mission is to enable cost-effective, smaller, lighter, and efficient power electronics and electric motors for electric traction drive systems (ETDSs) while maintaining performance of internal combustion engine (ICE)-based vehicles. The EETT also identifies technology gaps, establishes R&D targets, develops a roadmap to achieve technical targets and goals, and evaluates the R&D progress toward meeting the established R&D targets and goals.

  9. No Role for Motor Affordances in Visual Working Memory

    ERIC Educational Resources Information Center

    Pecher, Diane

    2013-01-01

    Motor affordances have been shown to play a role in visual object identification and categorization. The present study explored whether working memory is likewise supported by motor affordances. Use of motor affordances should be disrupted by motor interference, and this effect should be larger for objects that have motor affordances than for…

  10. 24 CFR 1000.101 - What is affordable housing?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false What is affordable housing? 1000... URBAN DEVELOPMENT NATIVE AMERICAN HOUSING ACTIVITIES Affordable Housing Activities § 1000.101 What is affordable housing? Eligible affordable housing is defined in section 4(2) of NAHASDA and is described...

  11. 24 CFR 1000.101 - What is affordable housing?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 4 2012-04-01 2012-04-01 false What is affordable housing? 1000... URBAN DEVELOPMENT NATIVE AMERICAN HOUSING ACTIVITIES Affordable Housing Activities § 1000.101 What is affordable housing? Eligible affordable housing is defined in section 4(2) of NAHASDA and is described...

  12. Options for Affordable Fission Surface Power Systems

    NASA Technical Reports Server (NTRS)

    Houts, Mike; Gaddis, Steve; Porter, Ron; VanDyke, Melissa; Martin Jim; Godfroy, Tom; Bragg-Sitton, Shannon; Garber, Anne; Pearson, Boise

    2006-01-01

    Fission surface power systems could provide abundant power anywhere on free surface of the moon or Mars. Locations could include permanently shaded regions on the moon and high latitudes on Mars. To be fully utilized; however, fission surface power systems must be safe, have adequate performance, and be affordable. This paper discusses options for the design and development of such systems.

  13. Are Selective Private and Public Colleges Affordable?

    ERIC Educational Resources Information Center

    Karikari, John A.; Dezhbakhsh, Hashem

    2013-01-01

    We examine college affordability under the existing pricing and financial aid system that awards both non need-based and need-based aid. Using data of freshmen attending a large number of selective private and public colleges in the USA, we find that the prices students actually pay for college have increased over time. Need-based grant aid has…

  14. Diabetes and the Affordable Care Act.

    PubMed

    Burge, Mark R; Schade, David S

    2014-07-01

    The Affordable Care Act--"Obamacare"--is the most important federal medical legislation to be enacted since Medicare. Although the goal of the Affordable Care Act is to improve healthcare coverage, access, and quality for all Americans, people with diabetes are especially poised to benefit from the comprehensive reforms included in the act. Signed into law in 2010, this massive legislation will slowly be enacted over the next 10 years. In the making for at least a decade, it will affect every person in the United States, either directly or indirectly. In this review, we discuss the major changes in healthcare that will take place in the next several years, including (1) who needs to purchase insurance on the Web-based exchange, (2) the cost to individuals and the rebates that they may expect, (3) the rules and regulations for purchasing insurance, (4) the characteristics of the different "metallic" insurance plans that are available, and (5) the states that have agreed to participate. With both tables and figures, we have tried to make the Affordable Care Act both understandable and appreciated. The goal of this comprehensive review is to highlight aspects of the Affordable Care Act that are of importance to practitioners who care for people with diabetes by discussing both the positive and the potentially negative aspects of the program as they relate to diabetes care.

  15. 24 CFR 572.120 - Affordability standards.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the additional monthly costs of utilities and other monthly housing costs, such as condominium and... at reasonable terms, energy conservation, and improvements that will entail low-cost maintenance. ... 24 Housing and Urban Development 3 2011-04-01 2010-04-01 true Affordability standards....

  16. Affordances of Instrumentation in General Chemistry Laboratories

    ERIC Educational Resources Information Center

    Sherman, Kristin Mary Daniels

    2010-01-01

    The purpose of this study is to find out what students in the first chemistry course at the undergraduate level (general chemistry for science majors) know about the affordances of instrumentation used in the general chemistry laboratory and how their knowledge develops over time. Overall, students see the PASCO(TM) system as a useful and accurate…

  17. 9 Tips for Affordable Student Trips

    ERIC Educational Resources Information Center

    Adams, Jonathan

    2013-01-01

    The trick to having a successful and affordable trip is planning ahead and planning thoroughly. Keep the spirits high and the costs low by following a well-traveled ensemble director's suggestions as presented in this article. These tips include finding local attractions that are unique to the city that the group will be visiting, looking at…

  18. Can the US afford a lunar base

    SciTech Connect

    Keaton, P.W.

    1986-01-01

    Establishing a lunar base will require steady funding for a decade or two. The question addressed here is whether such a large space project is affordable at this time. The relevant facts and methodology are presented so that the reader may formulate independent answers. It is shown that a permanent lunar base can be financed without increasing NASA's historical budgetary trends.

  19. Diabetes and the Affordable Care Act

    PubMed Central

    Schade, David S.

    2014-01-01

    Abstract The Affordable Care Act—“Obamacare”—is the most important federal medical legislation to be enacted since Medicare. Although the goal of the Affordable Care Act is to improve healthcare coverage, access, and quality for all Americans, people with diabetes are especially poised to benefit from the comprehensive reforms included in the act. Signed into law in 2010, this massive legislation will slowly be enacted over the next 10 years. In the making for at least a decade, it will affect every person in the United States, either directly or indirectly. In this review, we discuss the major changes in healthcare that will take place in the next several years, including (1) who needs to purchase insurance on the Web-based exchange, (2) the cost to individuals and the rebates that they may expect, (3) the rules and regulations for purchasing insurance, (4) the characteristics of the different “metallic” insurance plans that are available, and (5) the states that have agreed to participate. With both tables and figures, we have tried to make the Affordable Care Act both understandable and appreciated. The goal of this comprehensive review is to highlight aspects of the Affordable Care Act that are of importance to practitioners who care for people with diabetes by discussing both the positive and the potentially negative aspects of the program as they relate to diabetes care. PMID:24927108

  20. Options for Affordable Fission Surface Power Systems

    SciTech Connect

    Houts, Mike; Gaddis, Steve; Porter, Ron; Van Dyke, Melissa; Martin, Jim; Godfroy, Tom; Bragg-Sitton, Shannon; Garber, Anne; Pearson, Boise

    2006-07-01

    Fission surface power systems could provide abundant power anywhere on the surface of the moon or Mars. Locations could include permanently shaded regions on the moon and high latitudes on Mars. To be fully utilized, however, fission surface power systems must be safe, have adequate performance, and be affordable. This paper discusses options for the design and development of such systems. (authors)

  1. Actions and Affordances in Syntactic Ambiguity Resolution

    ERIC Educational Resources Information Center

    Chambers, Craig G.; Tanenhaus, Michael K.; Magnuson, James S.

    2004-01-01

    In 2 experiments, eye movements were monitored as participants followed instructions containing temporary syntactic ambiguities (e.g., "Pour the egg in the bowl over the flour"). The authors varied the affordances of task-relevant objects with respect to the action required by the instruction (e.g., whether 1 or both eggs in the visual workspace…

  2. Effects of broken affordance on visual extinction.

    PubMed

    Wulff, Melanie; Humphreys, Glyn W

    2015-01-01

    Previous studies have shown that visual extinction can be reduced if two objects are positioned to "afford" an action. Here we tested if this affordance effect was disrupted by "breaking" the affordance, i.e., if one of the objects actively used in the action had a broken handle. We assessed the effects of broken affordance on recovery from extinction in eight patients with right hemisphere lesions and left-sided extinction. Patients viewed object pairs that were or were not commonly used together and that were positioned for left- or right-hand actions. In the unrelated pair conditions, either two tools or two objects were presented. In line with previous research (e.g., Riddoch et al., 2006), extinction was reduced when action-related object pairs and when unrelated tool pairs were presented compared to unrelated object pairs. There was no significant difference in recovery rate between action-related (object-tool) and unrelated tool pairs. In addition, performance with action-related objects decreased when the tool appeared on the ipsilesional side compared to when it was on the contralesional side, but only when the tool handle was intact. There were minimal effects of breaking the handle of an object rather than a tool, and there was no effect of breaking the handle on either tools or objects on single item trials. The data suggest that breaking the handle of a tool lessens the degree to which it captures attention, with this attentional capture being strongest when the tool appears on the ipsilesional side. The capture of attention by the ipsilesional item then reduces the chance of detecting the contralesional stimulus. This attentional capture effect is mediated by the affordance to the intact tool.

  3. Traction drive for cryogenic boost pump. [hydrogen oxygen rocket engines

    NASA Technical Reports Server (NTRS)

    Meyer, S.; Connelly, R. E.

    1981-01-01

    Two versions of a Nasvytis multiroller traction drive were tested in liquid oxygen for possible application as cryogenic boost pump speed reduction drives for advanced hydrogen-oxygen rocket engines. The roller drive, with a 10.8:1 reduction ratio, was successfully run at up to 70,000 rpm input speed and up to 14.9 kW (20 hp) input power level. Three drive assemblies were tested for a total of about three hours of which approximately one hour was at nominal full speed and full power conditions. Peak efficiency of 60 percent was determined. There was no evidence of slippage between rollers for any of the conditions tested. The ball drive, a version using balls instead of one row of rollers, and having a 3.25:1 reduction ratio, failed to perform satisfactorily.

  4. Matrix identity and tractional forces influence indirect cardiac reprogramming

    PubMed Central

    Kong, Yen P.; Carrion, Bita; Singh, Rahul K.; Putnam, Andrew J.

    2013-01-01

    Heart regeneration through in vivo cardiac reprogramming has been demonstrated as a possible regenerative strategy. While it has been reported that cardiac reprogramming in vivo is more efficient than in vitro, the influence of the extracellular microenvironment on cardiac reprogramming remains incompletely understood. This understanding is necessary to improve the efficiency of cardiac reprogramming in order to implement this strategy successfully. Here we have identified matrix identity and cell-generated tractional forces as key determinants of the dedifferentiation and differentiation stages during reprogramming. Cell proliferation, matrix mechanics, and matrix microstructure are also important, but play lesser roles. Our results suggest that the extracellular microenvironment can be optimized to enhance cardiac reprogramming. PMID:24326998

  5. Spatial and temporal traction response in human airway smooth muscle cells

    NASA Technical Reports Server (NTRS)

    Tolic-Norrelykke, Iva Marija; Butler, James P.; Chen, Jianxin; Wang, Ning

    2002-01-01

    Tractions that cells exert on their substrates are essential in cell spreading, migration, and contraction. These tractions can be determined by plating the cells on a flexible gel and measuring the deformation of the gel by using fluorescent beads embedded just below the surface of the gel. In this article we describe the image correlation method (ICM) optimized for determining the displacement field of the gel under a contracting cell. For the calculation of the traction field from the displacement field we use the recently developed method of Fourier transform traction cytometry (FTTC). The ICM and FTTC methods are applied to human airway smooth muscle cells during stimulation with the contractile agonist histamine or the relaxing agonist isoproterenol. The overall intensity of the cell contraction (the median traction magnitude, the energy transferred from the cell to the gel, and the net contractile moment) increased after activation with histamine, and decreased after treatment with isoproterenol. Cells exhibited regional differences in the time course of traction during the treatment. Both temporal evolution and magnitude of traction increase induced by histamine varied markedly among different cell protrusions, whereas the nuclear region showed the smallest response. These results suggest that intracellular mediators of cell adhesion and contraction respond to contractile stimuli with different rates and intensities in different regions of the cell.

  6. Demonstrating the Viability and Affordability of Nuclear Surface Power Systems

    NASA Technical Reports Server (NTRS)

    Vandyke, Melissa K.

    2006-01-01

    A set of tasks have been identified to help demonstrate the viability, performance, and affordability of surface fission systems. Completion of these tasks will move surface fission systems closer to reality by demonstrating affordability and performance potential. Tasks include fabrication and test of a 19-pin section of a Surface Power Unit Demonstrator (SPUD); design, fabrication, and utilization of thermal simulators optimized for surface fission' applications; design, fabrication, and utilization of GPHS module thermal simulators; design, fabrication, and test of a fission surface power system shield; and work related to potential fission surface power fuel/clad systems. Work on the SPUD will feed directly into joint NASA MSFC/NASA GRC fabrication and test of a surface power plant Engineering Development Unit (EDU). The goal of the EDU will be to perform highly realistic thermal, structural, and electrical testing on an integrated fission surface power system. Fission thermal simulator work will help enable high fidelity non-nuclear testing of pumped NaK surface fission power systems. Radioisotope thermal simulator work will help enable design and development of higher power radioisotope systems (power ultimately limited by Pu-238 availability). Shield work is designed to assess the potential of using a water neutron shield on the surface of the moon. Fuels work is geared toward assessing the current potential of using fuels that have already flown in space.

  7. Hybrid electric vehicle power management system

    SciTech Connect

    Bissontz, Jay E.

    2015-08-25

    Level voltage levels/states of charge are maintained among a plurality of high voltage DC electrical storage devices/traction battery packs that are arrayed in series to support operation of a hybrid electric vehicle drive train. Each high voltage DC electrical storage device supports a high voltage power bus, to which at least one controllable load is connected, and at least a first lower voltage level electrical distribution system. The rate of power transfer from the high voltage DC electrical storage devices to the at least first lower voltage electrical distribution system is controlled by DC-DC converters.

  8. Surgical management of retinal diseases: proliferative diabetic retinopathy and traction retinal detachment.

    PubMed

    Cruz-Iñigo, Yousef J; Acabá, Luis A; Berrocal, Maria H

    2014-01-01

    Current indications for pars plana vitrectomy in patients with proliferative diabetic retinopathy (PDR) include vitreous hemorrhage, tractional retinal detachment (TRD), combined tractional and rhegmatogenous retinal detachment (CTRRD), diabetic macular edema associated with posterior hyaloidal traction, and anterior segment neovascularization with media opacities. This chapter will review the indications, surgical objectives, adjunctive pharmacotherapy, microincision surgical techniques, and outcomes of diabetic vitrectomy for PDR, TRD, and CTRRD. With the availability of new microincision vitrectomy technology, wide-angle microscope viewing systems, and pharmacologic agents, vitrectomy can improve visual acuity and achieve long-term anatomic stability in eyes with severe complications from PDR.

  9. Traction free finite elements with the assumed stress hybrid model. M.S. Thesis, 1981

    NASA Technical Reports Server (NTRS)

    Kafie, Kurosh

    1991-01-01

    An effective approach in the finite element analysis of the stress field at the traction free boundary of a solid continuum was studied. Conventional displacement and assumed stress finite elements were used in the determination of stress concentrations around circular and elliptical holes. Specialized hybrid elements were then developed to improve the satisfaction of prescribed traction boundary conditions. Results of the stress analysis indicated that finite elements which exactly satisfy the free stress boundary conditions are the most accurate and efficient in such problems. A general approach for hybrid finite elements which incorporate traction free boundaries of arbitrary geometry was formulated.

  10. The influence of surface dents and grooves on traction in sliding EHD point contacts

    NASA Technical Reports Server (NTRS)

    Cusano, C.; Wedeven, L. D.

    1983-01-01

    Changes in traction, caused by dents and grooves on a highly polished ball, are investigated as these defects approach and go through sliding elastohydrodynamic point contacts. The contacts are formed with the ball loading against a transparent disk. The ball and thus the topographical features are held stationary at various locations in the vicinity and within the contact while the disk is rotating. These topographical features can cause substantial changes in the traction when compared to traction obtained with smooth surfaces. Previously announced in STAR as N82-32734

  11. Affordances and the musically extended mind

    PubMed Central

    Krueger, Joel

    2014-01-01

    I defend a model of the musically extended mind. I consider how acts of “musicking” grant access to novel emotional experiences otherwise inaccessible. First, I discuss the idea of “musical affordances” and specify both what musical affordances are and how they invite different forms of entrainment. Next, I argue that musical affordances – via soliciting different forms of entrainment – enhance the functionality of various endogenous, emotion-granting regulative processes, drawing novel experiences out of us with an expanded complexity and phenomenal character. I argue that music therefore ought to be thought of as part of the vehicle needed to realize these emotional experiences. I appeal to different sources of empirical work to develop this idea. PMID:24432008

  12. An Affordable Open-Source Turbidimeter

    PubMed Central

    Kelley, Christopher D.; Krolick, Alexander; Brunner, Logan; Burklund, Alison; Kahn, Daniel; Ball, William P.; Weber-Shirk, Monroe

    2014-01-01

    Turbidity is an internationally recognized criterion for assessing drinking water quality, because the colloidal particles in turbid water may harbor pathogens, chemically reduce oxidizing disinfectants, and hinder attempts to disinfect water with ultraviolet radiation. A turbidimeter is an electronic/optical instrument that assesses turbidity by measuring the scattering of light passing through a water sample containing such colloidal particles. Commercial turbidimeters cost hundreds or thousands of dollars, putting them beyond the reach of low-resource communities around the world. An affordable open-source turbidimeter based on a single light-to-frequency sensor was designed and constructed, and evaluated against a portable commercial turbidimeter. The final product, which builds on extensive published research, is intended to catalyze further developments in affordable water and sanitation monitoring. PMID:24759114

  13. System Concepts for Affordable Fission Surface Power

    NASA Technical Reports Server (NTRS)

    Mason, Lee; Poston, David; Qualls, Louis

    2008-01-01

    This paper presents an overview of an affordable Fission Surface Power (FSP) system that could be used for NASA applications on the Moon and Mars. The proposed FSP system uses a low temperature, uranium dioxide-fueled, liquid metal-cooled fission reactor coupled to free-piston Stirling converters. The concept was determined by a 12 month NASA/DOE study that examined design options and development strategies based on affordability and risk. The system is considered a low development risk based on the use of terrestrial-derived reactor technology, high efficiency power conversion, and conventional materials. The low-risk approach was selected over other options that could offer higher performance and/or lower mass.

  14. America's Affordable Health Choices Act of 2009

    THOMAS, 111th Congress

    Rep. Dingell, John D. [D-MI-15

    2009-07-14

    10/14/2009 Placed on the Union Calendar, Calendar No. 168. (All Actions) Notes: For further action, see H.R.3590, which became Public Law 111-148 on 3/23/2010. H.R.3590, often referred to as the Affordable Care Act, is the bill that became the health care reform law. Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  15. Affordable Heavy Lift Capability: 2000-2004

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This custom bibliography from the NASA Scientific and Technical Information Program lists a sampling of records found in the NASA Aeronautics and Space Database. The scope of this topic includes technologies to allow robust, affordable access of cargo, particularly to low-Earth orbit. This area of focus is one of the enabling technologies as defined by NASA s Report of the President s Commission on Implementation of United States Space Exploration Policy, published in June 2004.

  16. Effects of broken affordance on visual extinction

    PubMed Central

    Wulff, Melanie; Humphreys, Glyn W.

    2015-01-01

    Previous studies have shown that visual extinction can be reduced if two objects are positioned to “afford” an action. Here we tested if this affordance effect was disrupted by “breaking” the affordance, i.e., if one of the objects actively used in the action had a broken handle. We assessed the effects of broken affordance on recovery from extinction in eight patients with right hemisphere lesions and left-sided extinction. Patients viewed object pairs that were or were not commonly used together and that were positioned for left- or right-hand actions. In the unrelated pair conditions, either two tools or two objects were presented. In line with previous research (e.g., Riddoch et al., 2006), extinction was reduced when action-related object pairs and when unrelated tool pairs were presented compared to unrelated object pairs. There was no significant difference in recovery rate between action-related (object-tool) and unrelated tool pairs. In addition, performance with action-related objects decreased when the tool appeared on the ipsilesional side compared to when it was on the contralesional side, but only when the tool handle was intact. There were minimal effects of breaking the handle of an object rather than a tool, and there was no effect of breaking the handle on either tools or objects on single item trials. The data suggest that breaking the handle of a tool lessens the degree to which it captures attention, with this attentional capture being strongest when the tool appears on the ipsilesional side. The capture of attention by the ipsilesional item then reduces the chance of detecting the contralesional stimulus. This attentional capture effect is mediated by the affordance to the intact tool. PMID:26441612

  17. The Affordable Care Act and emergency care.

    PubMed

    McClelland, Mark; Asplin, Brent; Epstein, Stephen K; Kocher, Keith Eric; Pilgrim, Randy; Pines, Jesse; Rabin, Elaine Judith; Rathlev, Niels Kumar

    2014-10-01

    The Affordable Care Act (ACA) will have far-reaching effects on the way health care is designed and delivered. Several elements of the ACA will directly affect both demand for ED care and expectations for its role in providing coordinated care. Hospitals will need to employ strategies to reduce ED crowding as the ACA expands insurance coverage. Discussions between EDs and primary care physicians about their respective roles providing acute unscheduled care would promote the goals of the ACA.

  18. Patient Protection and Affordable Care Act

    THOMAS, 111th Congress

    Rep. Rangel, Charles B. [D-NY-15

    2009-09-17

    03/23/2010 Became Public Law No: 111-148. (TXT | PDF) (All Actions) Notes: H.R.4872 makes a number of health-related financing and revenue changes to this bill. Read together, this bill and the health care-related provisions of H.R.4872 are commonly referred to as the Affordable Care Act (ACA). Tracker: This bill has the status Became LawHere are the steps for Status of Legislation:

  19. Affordances of instrumentation in general chemistry laboratories

    NASA Astrophysics Data System (ADS)

    Sherman, Kristin Mary Daniels

    The purpose of this study is to find out what students in the first chemistry course at the undergraduate level (general chemistry for science majors) know about the affordances of instrumentation used in the general chemistry laboratory and how their knowledge develops over time. Overall, students see the PASCO(TM) system as a useful and accurate measuring tool for general chemistry labs. They see the probeware as easy to use, portable, and able to interact with computers. Students find that the PASCO(TM) probeware system is useful in their general chemistry labs, more advanced chemistry labs, and in other science classes, and can be used in a variety of labs done in general chemistry. Students learn the affordances of the probeware through the lab manual, the laboratory teaching assistant, by trial and error, and from each other. The use of probeware systems provides lab instructors the opportunity to focus on the concepts illustrated by experiments and the opportunity to spend time discussing the results. In order to teach effectively, the instructor must know the correct name of the components involved, how to assemble and disassemble it correctly, how to troubleshoot the software, and must be able to replace broken or missing components quickly. The use of podcasts or Web-based videos should increase student understanding of affordances of the probeware.

  20. Demonstrating Cell Traction--Using Hens' Egg Vitelline Membrane as Substratum.

    ERIC Educational Resources Information Center

    Downie, Roger

    1987-01-01

    Suggests ways in which hens' egg vitelline membranes can be used to demonstrate cell traction effects. Reviews procedures for using and culturing the membranes and identifies topic areas for student projects. (ML)

  1. Rolling-element fatigue life with two synthetic cycloaliphatic traction fluids

    NASA Technical Reports Server (NTRS)

    Loewenthal, S. H.; Parker, R. J.

    1976-01-01

    The life potential of two synthetic cycloaliphatic hydrocarbon traction fluids in rolling element fatigue was evaluated in a five ball fatigue tester. Life comparisons with a MIL-L-23699 qualified tetraester oil showed that the traction test oils had good fatigue life performance, comparable to that of the tetraester oil. No statistically significant life differences between the traction fluids and the tetraester oil were exhibited under the accelerated fatigue test conditions. Erratic operating behavior was occasionally encountered during tests with the antiwear additive containing traction fluid for reasons thought to be related to excessive chemical activity under high contact pressure. This behavior occasionally resulted in premature test termination due to excessive surface distress and overheating.

  2. 75 FR 60482 - Proposed Extension of Information Collection Request Submitted for Public Comment; Affordable...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-30

    ... Comment; Affordable Care Act Enrollment Opportunity Notice Relating to Dependent Coverage; Affordable Care Act Grandfathered Health Plan Disclosure and Recordkeeping Requirement; Affordable Care Act Rescission Notice; Affordable Care Act Patient Protections Notice; Affordable Care Act......

  3. Multidimensional traction force microscopy reveals out-of-plane rotational moments about focal adhesions.

    PubMed

    Legant, Wesley R; Choi, Colin K; Miller, Jordan S; Shao, Lin; Gao, Liang; Betzig, Eric; Chen, Christopher S

    2013-01-15

    Recent methods have revealed that cells on planar substrates exert both shear (in-plane) and normal (out-of-plane) tractions against the extracellular matrix (ECM). However, the location and origin of the normal tractions with respect to the adhesive and cytoskeletal elements of cells have not been elucidated. We developed a high-spatiotemporal-resolution, multidimensional (2.5D) traction force microscopy to measure and model the full 3D nature of cellular forces on planar 2D surfaces. We show that shear tractions are centered under elongated focal adhesions whereas upward and downward normal tractions are detected on distal (toward the cell edge) and proximal (toward the cell body) ends of adhesions, respectively. Together, these forces produce significant rotational moments about focal adhesions in both protruding and retracting peripheral regions. Temporal 2.5D traction force microscopy analysis of migrating and spreading cells shows that these rotational moments are highly dynamic, propagating outward with the leading edge of the cell. Finally, we developed a finite element model to examine how rotational moments could be generated about focal adhesions in a thin lamella. Our model suggests that rotational moments can be generated largely via shear lag transfer to the underlying ECM from actomyosin contractility applied at the intracellular surface of a rigid adhesion of finite thickness. Together, these data demonstrate and probe the origin of a previously unappreciated multidimensional stress profile associated with adhesions and highlight the importance of new approaches to characterize cellular forces. PMID:23277584

  4. Rigid two-axis MEMS force plate for measuring cellular traction force

    NASA Astrophysics Data System (ADS)

    Takahashi, Hidetoshi; Jung, Uijin G.; Kan, Tetsuo; Tsukagoshi, Takuya; Matsumoto, Kiyoshi; Shimoyama, Isao

    2016-10-01

    Cellular traction force is one of the important factors for understanding cell behaviors, such as spreading, migration and differentiation. Cells are known to change their behavior according to the mechanical stiffness of the environment. However, the measurement of cell traction forces on a rigid environment has remained difficult. This paper reports a micro-electromechanical systems (MEMS) force plate that provides a cellular traction force measurement on a rigid substrate. Both the high force sensitivity and high stiffness of the substrate were obtained using piezoresistive sensing elements. The proposed force plate consists of a 70 µm  ×  15 µm  ×  5 µm base as the substrate for cultivating a bovine aortic smooth muscle cell, and the supporting beams with piezoresistors on the sidewall and the surface were used to measure the forces in both the horizontal and vertical directions. The spring constant and force resolution of the fabricated force plate in the horizontal direction were 0.2 N m-1 and less than 0.05 µN, respectively. The cell traction force was measured, and the traction force increased by approximately 1 µN over 30 min. These results demonstrate that the proposed force plate is applicable as an effective traction force measurement.

  5. Traction reveals mechanisms of wall-effects for microswimmers near boundaries

    NASA Astrophysics Data System (ADS)

    Shen, Xinhui; Marcos, -; Fu, Henry C.

    2015-11-01

    Swimming of microorganism near solid boundaries plays an important role in various biological processes, such as biofilm formation and the early stage of infection. The influence of a plane boundary on low-Reynolds number swimmers has frequently been studied using image systems for flow singularities. However, the effect of a boundary can also be expressed in terms of the flow caused by the force or traction exerted by the boundary on the fluid. Here we show that examining the traction pattern on the boundary caused by a nearby swimmer can yield physical insight into the effect of the boundary on swimming velocities. To illustrate this point, we investigate a three-sphere swimmer initially placed parallel to a solid planar wall. The three spheres are modelled as three stokeslets and the method of images for a stokeslet is employed to solve for the traction on the wall. When the swimmer is close to the boundary, the middle sphere and end spheres produce a quadrupolar and dipolar time-averaged traction, respectively, reflecting the internal structure of the swimmer. Far away from the boundary, the time-averaged traction of the swimmer is similar to that of a pure far-field quadrupole. Thus the traction patterns reveal how close the swimmer must be to the boundary for the internal structure of the swimmer to influence the boundary effects.

  6. Experimental studies about the impact of traction sand on urban road dust composition.

    PubMed

    Kupiainen, Kaarle; Tervahattu, Heikki; Räisänen, Mika

    2003-06-01

    Traffic causes enhanced PM(10) resuspension especially during spring in the US, Japan, Norway, Sweden and Finland, among other countries. The springtime PM(10) consists primarily of mineral matter from tyre-induced paved road surface wear and traction sand. In some countries, the majority of vehicles are equipped with studded tyres to enhance traction, which additionally increases road surface wear. Because the traction sand and the mineral matter from the pavement aggregate can have a similar mineralogical composition, it has been difficult to determine the source of the mineral fraction in the PM(10). In this study, homogenous traction sand and pavement aggregate with different mineralogical compositions were chosen to determine the sources of PM(10) particles by single particle analysis (SEM/EDX). This study was conducted in a test facility, which made it possible to rule out dust contributions from other sources. The ambient PM(10) concentrations were higher when traction sand was used, regardless of whether the tyres were studded or not. Surprisingly, the use of traction sand greatly increased the number of the particles originating from the pavement. It was concluded that sand must contribute to pavement wear. This phenomenon is called the sandpaper effect. An understanding of this is important to reduce harmful effects of springtime road dust in practical winter maintenance of urban roads

  7. High Resolution Traction Force Microscopy Based on Experimental and Computational Advances

    PubMed Central

    Sabass, Benedikt; Gardel, Margaret L.; Waterman, Clare M.; Schwarz, Ulrich S.

    2008-01-01

    Cell adhesion and migration crucially depend on the transmission of actomyosin-generated forces through sites of focal adhesion to the extracellular matrix. Here we report experimental and computational advances in improving the resolution and reliability of traction force microscopy. First, we introduce the use of two differently colored nanobeads as fiducial markers in polyacrylamide gels and explain how the displacement field can be computationally extracted from the fluorescence data. Second, we present different improvements regarding standard methods for force reconstruction from the displacement field, which are the boundary element method, Fourier-transform traction cytometry, and traction reconstruction with point forces. Using extensive data simulation, we show that the spatial resolution of the boundary element method can be improved considerably by splitting the elastic field into near, intermediate, and far field. Fourier-transform traction cytometry requires considerably less computer time, but can achieve a comparable resolution only when combined with Wiener filtering or appropriate regularization schemes. Both methods tend to underestimate forces, especially at small adhesion sites. Traction reconstruction with point forces does not suffer from this limitation, but is only applicable with stationary and well-developed adhesion sites. Third, we combine these advances and for the first time reconstruct fibroblast traction with a spatial resolution of ∼1 μm. PMID:17827246

  8. Influence of basketball shoe mass, outsole traction, and forefoot bending stiffness on three athletic movements.

    PubMed

    Worobets, Jay; Wannop, John William

    2015-09-01

    Prior research has shown that footwear can enhance athletic performance. However, public information is not available on what basketball shoe properties should be selected to maximise movement performance. Therefore, the purpose of the study was to investigate the influence of basketball shoe mass, outsole traction, and forefoot bending stiffness on sprinting, jumping, and cutting performance. Each of these three basketball shoe properties was systematically varied by ± 20% to produce three shoe conditions of varying mass, three conditions of varying traction, and three conditions of varying bending stiffness. Each shoe was tested by 20 recreational basketball players completing maximal effort sprints, vertical jumps, and a cutting drill. Outsole traction had the largest influence on performance, as the participants performed significantly worse in all tests when traction was decreased by 20% (p < 0.001), and performed significantly better in the cutting drill when traction was increased by 20% (p = 0.005). Forefoot bending stiffness had a moderate effect on sprint and cutting performance (p = 0.013 and p = 0.016 respectively) and shoe mass was found to have no effect on performance. Therefore, choosing a shoe with relatively high outsole traction and forefoot bending stiffness should be prioritised, and less concern should be focused on selecting the lightest shoe.

  9. Size and composition of airborne particles from pavement wear, tires, and traction sanding.

    PubMed

    Kupiainen, Kaarle J; Tervahattu, Heikki; Räisänen, Mika; Mäkelä, Timo; Aurela, Minna; Hillamo, Risto

    2005-02-01

    Mineral matter is an important component of airborne particles in urban areas. In northern cities of the world, mineral matter dominates PM10 during spring because of enhanced road abrasion caused by the use of antiskid methods, including studded tires and traction sanding. In this study, factors that affect formation of abrasion components of springtime road dust were assessed. Effects of traction sanding and tires on concentrations, mass size distribution, and composition of the particles were studied in a test facility. Lowest particle concentrations were observed in tests without traction sanding. The concentrations increased when traction sand was introduced and continued to increase as a function of the amount of aggregate dispersed. Emissions were additionally affected by type of tire, properties of traction sand aggregate, and driving speed. Aggregates with high fragmentation resistance and coarse grain size distribution had the lowest emissions. Over 90% of PM10 was mineral particles. Mineralogy of the dust and source apportionment showed that they originated from both traction sand and pavement aggregates. The remaining portion was mostly carbonaceous and originated from tires and road bitumen. Mass size distributions were dominated by coarse particles. Contribution of fine and submicron size ranges were approximately 15 and 10% in PM10, respectively. PMID:15757329

  10. Perceiving Affordances for Different Motor Skills

    PubMed Central

    Cole, Whitney G.; Chan, Gladys L. Y.; Vereijken, Beatrix; Adolph, Karen E.

    2013-01-01

    We examined several factors that affect people’s ability to perceive possibilities for action. In Experiment 1, 24 participants crossed expanses of various sizes in three conditions: leaping, a familiar, launching action system; arm-swinging on monkey bars, an unpracticed skill that uses the arms rather than the legs; and crawling on hands and knees, a disused skill that involves all four limbs. Before and after performing each action, participants gave verbal judgments about the largest gap they could cross. Participants scaled initial judgments to their actual abilities in all three conditions. But they considerably underestimated their abilities for leaping, a launching action, and for arm-swinging when it was performed as a launching action; judgments about crawling, a non-launching action, and arm-swinging when it was performed as a non-launching action were more accurate. Thus, launching actions appear to produce a deficit in perceiving affordances that is not ameliorated by familiarity with the action. However, after performing the actions, participants partially corrected for the deficiency and more accurately judged their abilities for launching actions—suggesting that even brief action experience facilitates the perception of affordances. In Experiment 2, we confirmed that the deficit was due to the launching nature of the leaping and arm-swinging actions in Experiment 1. We asked an additional 12 participants to cross expanses using two non-launching actions using the legs (stepping across an expanse) and the arms (reaching across an expanse). Participants were highly accurate when judging affordances for these actions, supporting launching as the cause of the underestimation reported in Experiment 1. PMID:23411672

  11. Contraceptive Coverage and the Affordable Care Act.

    PubMed

    Tschann, Mary; Soon, Reni

    2015-12-01

    A major goal of the Patient Protection and Affordable Care Act is reducing healthcare spending by shifting the focus of healthcare toward preventive care. Preventive services, including all FDA-approved contraception, must be provided to patients without cost-sharing under the ACA. No-cost contraception has been shown to increase uptake of highly effective birth control methods and reduce unintended pregnancy and abortion; however, some institutions and corporations argue that providing contraceptive coverage infringes on their religious beliefs. The contraceptive coverage mandate is evolving due to legal challenges, but it has already demonstrated success in reducing costs and improving access to contraception. PMID:26598303

  12. Breastfeeding and the Affordable Care Act.

    PubMed

    Hawkins, Summer Sherburne; Dow-Fleisner, Sarah; Noble, Alice

    2015-10-01

    Mothers who receive or qualify for the Women, Infants, and Children (WIC) program or have lower income are less likely to start and continue breastfeeding than their more advantaged counterparts. The Patient Protection and Affordable Care Act (ACA) requires employers to provide break time and space to express breast milk and requires insurance companies to cover breastfeeding support, supplies, and counseling at no cost to mothers. This ACA benefit does not extend to all Medicaid recipients or women in the WIC program. Legislative and regulatory efforts are needed to provide comprehensive coverage for all women and reduce disparities in breastfeeding.

  13. Contraceptive Coverage and the Affordable Care Act.

    PubMed

    Tschann, Mary; Soon, Reni

    2015-12-01

    A major goal of the Patient Protection and Affordable Care Act is reducing healthcare spending by shifting the focus of healthcare toward preventive care. Preventive services, including all FDA-approved contraception, must be provided to patients without cost-sharing under the ACA. No-cost contraception has been shown to increase uptake of highly effective birth control methods and reduce unintended pregnancy and abortion; however, some institutions and corporations argue that providing contraceptive coverage infringes on their religious beliefs. The contraceptive coverage mandate is evolving due to legal challenges, but it has already demonstrated success in reducing costs and improving access to contraception.

  14. Breastfeeding and the Affordable Care Act.

    PubMed

    Hawkins, Summer Sherburne; Dow-Fleisner, Sarah; Noble, Alice

    2015-10-01

    Mothers who receive or qualify for the Women, Infants, and Children (WIC) program or have lower income are less likely to start and continue breastfeeding than their more advantaged counterparts. The Patient Protection and Affordable Care Act (ACA) requires employers to provide break time and space to express breast milk and requires insurance companies to cover breastfeeding support, supplies, and counseling at no cost to mothers. This ACA benefit does not extend to all Medicaid recipients or women in the WIC program. Legislative and regulatory efforts are needed to provide comprehensive coverage for all women and reduce disparities in breastfeeding. PMID:26318941

  15. 12 CFR 1807.400 - Affordable housing-general.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 9 2012-01-01 2012-01-01 false Affordable housing-general. 1807.400 Section 1807.400 Banks and Banking COMMUNITY DEVELOPMENT FINANCIAL INSTITUTIONS FUND, DEPARTMENT OF THE TREASURY CAPITAL MAGNET FUND Qualification as Affordable Housing § 1807.400 Affordable...

  16. 12 CFR 1807.402 - Affordable housing-homeownership.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 10 2014-01-01 2014-01-01 false Affordable housing-homeownership. 1807.402 Section 1807.402 Banks and Banking COMMUNITY DEVELOPMENT FINANCIAL INSTITUTIONS FUND, DEPARTMENT OF THE TREASURY CAPITAL MAGNET FUND Qualification as Affordable Housing § 1807.402 Affordable...

  17. 12 CFR 1807.400 - Affordable housing-general.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 9 2013-01-01 2013-01-01 false Affordable housing-general. 1807.400 Section 1807.400 Banks and Banking COMMUNITY DEVELOPMENT FINANCIAL INSTITUTIONS FUND, DEPARTMENT OF THE TREASURY CAPITAL MAGNET FUND Qualification as Affordable Housing § 1807.400 Affordable...

  18. 12 CFR 1807.402 - Affordable housing-homeownership.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 7 2011-01-01 2011-01-01 false Affordable housing-homeownership. 1807.402 Section 1807.402 Banks and Banking COMMUNITY DEVELOPMENT FINANCIAL INSTITUTIONS FUND, DEPARTMENT OF THE TREASURY CAPITAL MAGNET FUND Qualification as Affordable Housing § 1807.402 Affordable...

  19. 12 CFR 1807.402 - Affordable housing-homeownership.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 9 2012-01-01 2012-01-01 false Affordable housing-homeownership. 1807.402 Section 1807.402 Banks and Banking COMMUNITY DEVELOPMENT FINANCIAL INSTITUTIONS FUND, DEPARTMENT OF THE TREASURY CAPITAL MAGNET FUND Qualification as Affordable Housing § 1807.402 Affordable...

  20. 12 CFR 1807.400 - Affordable housing-general.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 7 2011-01-01 2011-01-01 false Affordable housing-general. 1807.400 Section 1807.400 Banks and Banking COMMUNITY DEVELOPMENT FINANCIAL INSTITUTIONS FUND, DEPARTMENT OF THE TREASURY CAPITAL MAGNET FUND Qualification as Affordable Housing § 1807.400 Affordable...

  1. 12 CFR 1807.400 - Affordable housing-general.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 10 2014-01-01 2014-01-01 false Affordable housing-general. 1807.400 Section 1807.400 Banks and Banking COMMUNITY DEVELOPMENT FINANCIAL INSTITUTIONS FUND, DEPARTMENT OF THE TREASURY CAPITAL MAGNET FUND Qualification as Affordable Housing § 1807.400 Affordable...

  2. 12 CFR 1807.402 - Affordable housing-homeownership.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 9 2013-01-01 2013-01-01 false Affordable housing-homeownership. 1807.402 Section 1807.402 Banks and Banking COMMUNITY DEVELOPMENT FINANCIAL INSTITUTIONS FUND, DEPARTMENT OF THE TREASURY CAPITAL MAGNET FUND Qualification as Affordable Housing § 1807.402 Affordable...

  3. Keratocytes Generate Traction Forces in Two PhasesV⃞

    PubMed Central

    Burton, Kevin; Park, Jung H.; Taylor, D. Lansing

    1999-01-01

    Forces generated by goldfish keratocytes and Swiss 3T3 fibroblasts have been measured with nanonewton precision and submicrometer spatial resolution. Differential interference contrast microscopy was used to visualize deformations produced by traction forces in elastic substrata, and interference reflection microscopy revealed sites of cell-substratum adhesions. Force ranged from a few nanonewtons at submicrometer spots under the lamellipodium to several hundred nanonewtons under the cell body. As cells moved forward, centripetal forces were applied by lamellipodia at sites that remained stationary on the substratum. Force increased and abruptly became lateral at the boundary of the lamellipodium and the cell body. When the cell retracted at its posterior margin, cell-substratum contact area decreased more rapidly than force, so that stress (force divided by area) increased as the cell pulled away. An increase in lateral force was associated with widening of the cell body. These mechanical data suggest an integrated, two-phase mechanism of cell motility: (1) low forces in the lamellipodium are applied in the direction of cortical flow and cause the cell body to be pulled forward; and (2) a component of force at the flanks pulls the rear margins forward toward the advancing cell body, whereas a large lateral component contributes to detachment of adhesions without greatly perturbing forward movement. PMID:10564269

  4. Affordable proteomics: the two-hybrid systems.

    PubMed

    Gillespie, Marc

    2003-06-01

    Numerous proteomic methodologies exist, but most require a heavy investment in expertise and technology. This puts these approaches out of reach for many laboratories and small companies, rarely allowing proteomics to be used as a pilot approach for biomarker or target identification. Two proteomic approaches, 2D gel electrophoresis and the two-hybrid systems, are currently available to most researchers. The two-hybrid systems, though accommodating to large-scale experiments, were originally designed as practical screens, that by comparison to current proteomics tools were small-scale, affordable and technically feasible. The screens rapidly generated data, identifying protein interactions that were previously uncharacterized. The foundation for a two-hybrid proteomic investigation can be purchased as separate kits from a number of companies. The true power of the technique lies not in its affordability, but rather in its portability. The two-hybrid system puts proteomics back into laboratories where the output of the screens can be evaluated by researchers with experience in the particular fields of basic research, cancer biology, toxicology or drug development.

  5. FY2009 Oak Ridge National Laboratory Annual Progress Report for the Power Electronics and Electric Machinery

    SciTech Connect

    Olszewski, Mitchell

    2009-11-01

    system and whether the efficiency and performance targets at the vehicle level have been achieved. The research performed under this subprogram will help remove technical and cost barriers to enable the development of technology for use in such advanced vehicles as hybrid electric vehicles (HEVs), plug-in HEVs (PHEVs), all electric vehicles, and fuel-cell-powered automobiles that meet the goals of the Vehicle Technologies Program. A key element in making these advanced vehicles practical is providing an affordable electric traction drive system. This will require attaining weight, volume, and cost targets for the power electronics and electrical machines subsystems of the traction drive system. Areas of development include these: (1) novel traction motor designs that result in increased power density and lower cost; (2) inverter technologies involving new topologies to achieve higher efficiency, with the ability to accommodate higher-temperature environments while achieving high reliability; (3) converter concepts that employ means of reducing the component count and integrating functionality to decrease size, weight, and cost; (4) new onboard battery charging concepts that result in decreased cost and size; (5) more effective thermal control and packaging technologies; and (6) integrated motor/inverter concepts. ORNL's Power Electronics and Electric Machinery Research Center conducts fundamental research, evaluates hardware, and assists in the technical direction of the DOE Vehicle Technologies Program, APEEM subprogram. In this role, ORNL serves on the FreedomCAR Electrical and Electronics Technical Team, evaluates proposals for DOE, and lends its technological expertise to the direction of projects and evaluation of developing technologies. ORNL also executes specific projects for DOE. The following report discusses those projects carried out in FY 2009 and conveys highlights of their accomplishments. Numerous project reviews, technical reports, and papers have been

  6. Time-dependent traction force microscopy for cancer cells as a measure of invasiveness.

    PubMed

    Peschetola, Valentina; Laurent, Valérie M; Duperray, Alain; Michel, Richard; Ambrosi, Davide; Preziosi, Luigi; Verdier, Claude

    2013-04-01

    The migration of tumor cells of different degrees of invasivity is studied, on the basis of the traction forces exerted in time on soft substrates (Young modulus∼10 kPa). It is found that the outliers of the traction stresses can be an effective indicator to distinguish cancer cell lines of different invasiveness. Here, we test two different epithelial bladder cancer cell lines, one invasive (T24), and a less invasive one (RT112). Invasive cancer cells move in a nearly periodic motion, with peaks in velocity corresponding to higher traction forces exerted on the substrate, whereas less invasive cells develop traction stresses almost constant in time. The dynamics of focal adhesions (FAs) as well as cytoskeleton features reveals that different mechanisms are activated to migrate: T24 cells show an interconnected cytoskeleton linked to mature adhesion sites, leading to small traction stresses, whereas less invasive cells (RT112) show a less-structured cytoskeleton and unmature adhesions corresponding to higher traction stresses. Migration velocities are smaller in the case of less invasive cells. The mean squared displacement shows super-diffusive motion in both cases with higher exponent for the more invasive cancer cells. Further correlations between traction forces and the actin cytoskeleton reveal an unexpected pattern of a large actin rim at the RT112 cell edge where higher forces are colocalized, whereas a more usual cytoskeleton structure with stress fibers and FAs are found for T24 cancer cells. We conjecture that this kind of analysis can be useful to classify cancer cell invasiveness.

  7. Hierarchical nesting of affordances in a tool use task.

    PubMed

    Wagman, Jeffrey B; Caputo, Sarah E; Stoffregen, Thomas A

    2016-10-01

    In studying the perception of affordances, researchers have typically identified a single affordance and designed experiments to evaluate the perception of that affordance. Yet in daily life, multiple affordances always exist. One consequence of this is that there may be higher order, means-ends relations between different affordances. In 4 experiments, we created situations in which lower order, subordinate affordances could affect the realization of higher order, superordinate affordances, and we asked whether participants were sensitive to these hierarchical, nested relations. Participants wielded tools that varied in length, mass, and mass distribution. In Experiments 1 and 2, we asked them to evaluate these tools in terms of their suitability for executing specific interactions with target objects (striking vs. poking) that were positioned at different distances. In Experiments 3 and 4, we asked participants to select rods and masses and then to assemble them into tools that could be used to execute specific interactions with target objects at different distances. The results were compatible with the hypothesis that participants were simultaneously sensitive to affordances for tool assembly and affordances for tool use. We argue that the nesting of affordances is characteristic of many situations in daily life and that, consequently, sensitivity to hierarchical, means-ends relations among affordances may be an essential characteristic of perceptually guided action. (PsycINFO Database Record PMID:27668424

  8. Hierarchical nesting of affordances in a tool use task.

    PubMed

    Wagman, Jeffrey B; Caputo, Sarah E; Stoffregen, Thomas A

    2016-10-01

    In studying the perception of affordances, researchers have typically identified a single affordance and designed experiments to evaluate the perception of that affordance. Yet in daily life, multiple affordances always exist. One consequence of this is that there may be higher order, means-ends relations between different affordances. In 4 experiments, we created situations in which lower order, subordinate affordances could affect the realization of higher order, superordinate affordances, and we asked whether participants were sensitive to these hierarchical, nested relations. Participants wielded tools that varied in length, mass, and mass distribution. In Experiments 1 and 2, we asked them to evaluate these tools in terms of their suitability for executing specific interactions with target objects (striking vs. poking) that were positioned at different distances. In Experiments 3 and 4, we asked participants to select rods and masses and then to assemble them into tools that could be used to execute specific interactions with target objects at different distances. The results were compatible with the hypothesis that participants were simultaneously sensitive to affordances for tool assembly and affordances for tool use. We argue that the nesting of affordances is characteristic of many situations in daily life and that, consequently, sensitivity to hierarchical, means-ends relations among affordances may be an essential characteristic of perceptually guided action. (PsycINFO Database Record

  9. Social affordances and the possibility of ecological linguistics.

    PubMed

    Kono, Tetsuya

    2009-12-01

    This paper includes an effort to extend the notion of affordance from a philosophical point of view the importance of ecological approach for social psychology, ethics, and linguistics. Affordances are not always merely physical but also interpersonal and social. I will conceptualize affordance in general and social affordance in particular, and will elucidate the relation between intentional action and affordances, and that between affordances and free will. I will also focus on the relation between social institution and affordance. An extended theory of affordances can provide a way to analyze in concrete ways how social institution works as an implicit background of interpersonal interactions. Ecological approach considers social institution as the producer and maintainer of affordances. Social institutions construct the niches for human beings. Finally, I will argue the possibility of the ecological linguistics. Language is a social institution. The system of signs is the way to articulate and differentiate interpersonal affordances. Language acquires its meaning, i.e. communicative power in the interpersonal interactions, and interpersonal interactions, in turn, develop and are elaborated through the usage of signs. Communication is seen as never aimed to transmit inner ideas to others, but to guide and adjust the behaviors of others thorough articulating the affordance of responsible-ness.

  10. Piecing Together the College Affordability Puzzle: Student Characteristics and Patterns of (Un)Affordability

    ERIC Educational Resources Information Center

    Welbeck, Rashida; Diamond, John; Mayer, Alexander; Richburg-Hayes, Lashawn

    2014-01-01

    The cost of attending college has risen sharply over the last 40 years. Although more credit and grant aid have been made available to students, there are still major gaps between aid and the cost of attendance for many students in the United States, all of whom are left to figure out whether they can afford the remaining costs associated with…

  11. NASA's Space Launch System: Affordability for Sustainability

    NASA Technical Reports Server (NTRS)

    May, Todd A.; Creech, Stephen D.

    2012-01-01

    The National Aeronautics and Space Administration's (NASA) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is charged with delivering a new capability for human exploration beyond Earth orbit in an austere economic climate. But the SLS value is clear and codified in United States (U.S.) budget law. The SLS Program knows that affordability is the key to sustainability and will provide an overview of initiatives designed to fit within the funding guidelines by using existing engine assets and hardware now in testing to meet a first launch by 2017 within the projected budget. It also has a long-range plan to keep the budget flat, yet evolve the 70-tonne (t) initial lift capability to 130-t lift capability after the first two flights. To achieve the evolved configuration, advanced technologies must offer appropriate return on investment to be selected through the competitive process. For context, the SLS will be larger than the Saturn V that took 12 men on 6 trips for a total of 11 days on the lunar surface some 40 years ago. Astronauts train for long-duration voyages on platforms such as the International Space Station, but have not had transportation to go beyond Earth orbit in modern times, until now. To arrive at the launch vehicle concept, the SLS Program conducted internal engineering and business studies that have been externally validated by industry and reviewed by independent assessment panels. In parallel with SLS concept studies, NASA is now refining its mission manifest, guided by U.S. space policy and the Global Exploration Roadmap, which reflects the mutual goals of a dozen member nations. This mission planning will converge with a flexible heavy-lift rocket that can carry international crews and the air, water, food, and equipment they need for extended trips to asteroids and Mars. In addition, the SLS capability will accommodate very large science instruments and other payloads, using a series of modular fairings and

  12. Affordable Laser Communication in the Classroom

    NASA Astrophysics Data System (ADS)

    Walker, Constance E.; Sparks, R.; Pompea, S.

    2006-12-01

    Several companies sell systems that illustrate laser communication such as Arbor Scientific1. These systems can be too expensive for classroom use. We will demonstrate a technique to modulate a standard diode laser using a microphone or other sound source that is capable of transmitting voice and music. This affordable system can transmit over 350 feet using simple, inexpensive parts readily available at your local electronics store. We will provide a list of parts necessary for assembly, detailed assembly instructions, as well as some suggested investigations using the laser communication system. This system can be used in the classroom either as a demonstration or hands-on activity to explore the physics and technology involved, citing more sophisticated laser communication systems on board spacecraft such as the Mercury Messenger Mission and the Mars Telecommunications Orbiter. 1http://www.arborsci.com

  13. Why epidemiologists cannot afford to ignore poverty.

    PubMed

    Krieger, Nancy

    2007-11-01

    Epidemiologists cannot afford to ignore poverty. To do so would, first, wrongly obscure the devastating impact of poverty on population health, and, second, undercut our commitment to scientific rigor. At issue is doing correct science, not "politically correct" science. Blot poverty and inequity from view, and not only will we contribute to making suffering invisible but our understanding of disease etiology and distribution will be marred. To make this case, I address current debates about the causal relationships between poverty and health, and provide examples of how failing to consider the impact of socioeconomic position has biased epidemiologic knowledge and harmed the public's health. By definition, the people we study are simultaneously social beings and biologic organisms-and we cannot study the latter without taking into account the former. It is the responsibility of all epidemiologists, and not only social epidemiologists, to keep in mind the connections between poverty and health. PMID:18049180

  14. Why epidemiologists cannot afford to ignore poverty.

    PubMed

    Krieger, Nancy

    2007-11-01

    Epidemiologists cannot afford to ignore poverty. To do so would, first, wrongly obscure the devastating impact of poverty on population health, and, second, undercut our commitment to scientific rigor. At issue is doing correct science, not "politically correct" science. Blot poverty and inequity from view, and not only will we contribute to making suffering invisible but our understanding of disease etiology and distribution will be marred. To make this case, I address current debates about the causal relationships between poverty and health, and provide examples of how failing to consider the impact of socioeconomic position has biased epidemiologic knowledge and harmed the public's health. By definition, the people we study are simultaneously social beings and biologic organisms-and we cannot study the latter without taking into account the former. It is the responsibility of all epidemiologists, and not only social epidemiologists, to keep in mind the connections between poverty and health.

  15. Affordable Care Act and Diabetes Mellitus.

    PubMed

    Shi, Qian; Nellans, Frank P; Shi, Lizheng

    2015-12-01

    The Affordable Care Act (ACA) has the potential for great impact on U.S. health care, especially for chronic disease patients requiring long-term care and management. The act was designed to improve insurance coverage, health care access, and quality of care for all Americans, which will assist patients with diabetes mellitus in acquiring routine monitoring and diabetes-related complication screening for better health management and outcomes. There is great potential for patients with diabetes to benefit from the new policy mandating health insurance coverage and plan improvement, Medicaid expansion, minimum coverage guarantees, and free preventative care. However, policy variability among states and ACA implementation present challenges to people with diabetes in understanding and optimizing ACA impact. This paper aims to select the most influential components of the ACA as relates to people with diabetes and discuss how the ACA may improve health care for this vulnerable population.

  16. Employer Reactions to the Affordable Care Act.

    PubMed

    Muller, Leslie A; Isely, Paul; Levin, Adelin

    2015-01-01

    Although the implementation of parts of the Affordable Care Act (ACA) was delayed until 2015, many firms had already made changes to their health insurance plans and their business practices. This article reports results from a survey administered to western Michigan firms in October 2013 requesting information on any changes they made in response to ACA. The authors found that although 89% of employers planned to offer health insurance in 2014, that number dropped to 66% in 2015. The main ways organizations were controlling health costs were by changing prescription coverage, passing on the costs to employees through higher copays and premiums and offering more high-deductible health plans with health savings accounts. Employers also were altering business practices by decreasing future hiring and decreasing the hours of part-time workers. The authors find that many of these changes were due to the uncertainty firms were facing during the ACA implementation process. PMID:26540944

  17. Traction Drive Inverter Cooling with Submerged Liquid Jet Impingement on Microfinned Enhanced Surfaces (Presentation)

    SciTech Connect

    Waye, S.; Narumanchi, S.; Moreno, G.

    2014-09-01

    Jet impingement is one means to improve thermal management for power electronics in electric-drive traction vehicles. Jet impingement on microfin-enhanced surfaces further augments heat transfer and thermal performance. A channel flow heat exchanger from a commercial inverter was characterized as a baseline system for comparison with two new prototype designs using liquid jet impingement on plain and microfinned enhanced surfaces. The submerged jets can target areas with the highest heat flux to provide local cooling, such as areas under insulated-gate bipolar transistors and diode devices. Low power experiments, where four diodes were powered, dissipated 105 W of heat and were used to validate computational fluid dynamics modeling of the baseline and prototype designs. Experiments and modeling used typical automotive flow rates using water-ethylene glycol as a coolant (50%-50% by volume). The computational fluid dynamics model was used to predict full inverter power heat dissipation. The channel flow and jet impingement configurations were tested at full inverter power of 40 to 100 kW (output power) on a dynamometer, translating to an approximate heat dissipation of 1 to 2 kW. With jet impingement, the cold plate material is not critical for the thermal pathway. A high-temperature plastic was used that could eventually be injection molded or formed, with the jets formed from a basic aluminum plate with orifices acting as nozzles. Long-term reliability of the jet nozzles and impingement on enhanced surfaces was examined. For jet impingement on microfinned surfaces, thermal performance increased 17%. Along with a weight reduction of approximately 3 kg, the specific power (kW/kg) increased by 36%, with an increase in power density (kW/L) of 12% compared with the baseline channel flow configuration.

  18. Oak Ridge National Laboratory Annual Progress Report for the Power Electronics and Electric Machinery Program

    SciTech Connect

    Olszewski, M.

    2008-10-15

    performance targets at the vehicle level have been achieved. The research performed under this subprogram will help remove technical and cost barriers to enable the development of technology for use in such advanced vehicles as hybrid electric vehicles (HEVs), plug-in HEVs, and fuel-cell-powered automobiles that meet the goals of the Vehicle Technologies Program. A key element in making HEVs practical is providing an affordable electric traction drive system. This will require attaining weight, volume, and cost targets for the power electronics and electrical machines subsystems of the traction drive system. Areas of development include these: (1) novel traction motor designs that result in increased power density and lower cost; (2) inverter technologies involving new topologies to achieve higher efficiency and the ability to accommodate higher-temperature environments; (3) converter concepts that employ means of reducing the component count and integrating functionality to decrease size, weight, and cost; (4) more effective thermal control and packaging technologies; and (5) integrated motor/inverter concepts. The Oak Ridge National Laboratory's (ORNL's) Power Electronics and Electric Machinery Research Center conducts fundamental research, evaluates hardware, and assists in the technical direction of the DOE Vehicle Technologies Program, APEEM subprogram. In this role, ORNL serves on the FreedomCAR Electrical and Electronics Technical Team, evaluates proposals for DOE, and lends its technological expertise to the direction of projects and evaluation of developing technologies.

  19. Simple Electric Vehicle Simulation

    1993-07-29

    SIMPLEV2.0 is an electric vehicle simulation code which can be used with any IBM compatible personal computer. This general purpose simulation program is useful for performing parametric studies of electric and series hybrid electric vehicle performance on user input driving cycles.. The program is run interactively and guides the user through all of the necessary inputs. Driveline components and the traction battery are described and defined by ASCII files which may be customized by themore » user. Scaling of these components is also possible. Detailed simulation results are plotted on the PC monitor and may also be printed on a printer attached to the PC.« less

  20. For whom the cells pull: Hydrogel and micropost devices for measuring traction forces.

    PubMed

    Ribeiro, Alexandre J S; Denisin, Aleksandra K; Wilson, Robin E; Pruitt, Beth L

    2016-02-01

    While performing several functions, adherent cells deform their surrounding substrate via stable adhesions that connect the intracellular cytoskeleton to the extracellular matrix. The traction forces that deform the substrate are studied in mechanotrasduction because they are affected by the mechanics of the extracellular milieu. We review the development and application of two methods widely used to measure traction forces generated by cells on 2D substrates: (i) traction force microscopy with polyacrylamide hydrogels and (ii) calculation of traction forces with arrays of deformable microposts. Measuring forces with these methods relies on measuring substrate displacements and converting them into forces. We describe approaches to determine force from displacements and elaborate on the necessary experimental conditions for this type of analysis. We emphasize device fabrication, mechanical calibration of substrates and covalent attachment of extracellular matrix proteins to substrates as key features in the design of experiments to measure cell traction forces with polyacrylamide hydrogels or microposts. We also report the challenges and achievements in integrating these methods with platforms for the mechanical stimulation of adherent cells. The approaches described here will enable new studies to understand cell mechanical outputs as a function of mechanical inputs and advance the understanding of mechanotransduction mechanisms.

  1. Effects of intermittent traction therapy in an experimental spinal column model.

    PubMed

    Shin, Jeong-Hun; Jun, Seung-lyul; Lee, Young-Jun; Kim, Jae-Hyo; Hwang, Sung-Yeoun; Ahn, Seong-Hun

    2014-04-01

    Traction therapy, which is known to be a treatment method for scoliosis, one of many muscles disease, has been used since Hippocrates introduced it. However, the effects of traction therapy are still not clear. In addition, the meridian sinew theory, which is related to muscle treatment and is mentioned in the book on meridian sinews in the Miraculous Pivot of Huangdi's Internal Classic, has not been the subject of much study. For these reasons, experimental spinal models were made for this study to observe and analyze the lengths of vertebral interspaces after intermittent traction therapy, which is known to be excellent among muscle treatment methods, with various tensile forces. The results showed that the effects of intermittent traction therapy were unclear and that it might be harmful, especially when the pain was induced by muscle weakness. Because the results of this study on intermittent traction therapy were different from those expected from osteopathy or craniosacral theory, better studies of the subject are necessary. PMID:24745867

  2. Free Form Deformation–Based Image Registration Improves Accuracy of Traction Force Microscopy

    PubMed Central

    Jorge-Peñas, Alvaro; Izquierdo-Alvarez, Alicia; Aguilar-Cuenca, Rocio; Vicente-Manzanares, Miguel; Garcia-Aznar, José Manuel; Van Oosterwyck, Hans; de-Juan-Pardo, Elena M.; Ortiz-de-Solorzano, Carlos; Muñoz-Barrutia, Arrate

    2015-01-01

    Traction Force Microscopy (TFM) is a widespread method used to recover cellular tractions from the deformation that they cause in their surrounding substrate. Particle Image Velocimetry (PIV) is commonly used to quantify the substrate’s deformations, due to its simplicity and efficiency. However, PIV relies on a block-matching scheme that easily underestimates the deformations. This is especially relevant in the case of large, locally non-uniform deformations as those usually found in the vicinity of a cell’s adhesions to the substrate. To overcome these limitations, we formulate the calculation of the deformation of the substrate in TFM as a non-rigid image registration process that warps the image of the unstressed material to match the image of the stressed one. In particular, we propose to use a B-spline -based Free Form Deformation (FFD) algorithm that uses a connected deformable mesh to model a wide range of flexible deformations caused by cellular tractions. Our FFD approach is validated in 3D fields using synthetic (simulated) data as well as with experimental data obtained using isolated endothelial cells lying on a deformable, polyacrylamide substrate. Our results show that FFD outperforms PIV providing a deformation field that allows a better recovery of the magnitude and orientation of tractions. Together, these results demonstrate the added value of the FFD algorithm for improving the accuracy of traction recovery. PMID:26641883

  3. Free Form Deformation-Based Image Registration Improves Accuracy of Traction Force Microscopy.

    PubMed

    Jorge-Peñas, Alvaro; Izquierdo-Alvarez, Alicia; Aguilar-Cuenca, Rocio; Vicente-Manzanares, Miguel; Garcia-Aznar, José Manuel; Van Oosterwyck, Hans; de-Juan-Pardo, Elena M; Ortiz-de-Solorzano, Carlos; Muñoz-Barrutia, Arrate

    2015-01-01

    Traction Force Microscopy (TFM) is a widespread method used to recover cellular tractions from the deformation that they cause in their surrounding substrate. Particle Image Velocimetry (PIV) is commonly used to quantify the substrate's deformations, due to its simplicity and efficiency. However, PIV relies on a block-matching scheme that easily underestimates the deformations. This is especially relevant in the case of large, locally non-uniform deformations as those usually found in the vicinity of a cell's adhesions to the substrate. To overcome these limitations, we formulate the calculation of the deformation of the substrate in TFM as a non-rigid image registration process that warps the image of the unstressed material to match the image of the stressed one. In particular, we propose to use a B-spline -based Free Form Deformation (FFD) algorithm that uses a connected deformable mesh to model a wide range of flexible deformations caused by cellular tractions. Our FFD approach is validated in 3D fields using synthetic (simulated) data as well as with experimental data obtained using isolated endothelial cells lying on a deformable, polyacrylamide substrate. Our results show that FFD outperforms PIV providing a deformation field that allows a better recovery of the magnitude and orientation of tractions. Together, these results demonstrate the added value of the FFD algorithm for improving the accuracy of traction recovery. PMID:26641883

  4. FY2010 Oak Ridge National Laboratory Annual Progress Report for the Power Electronics and Electric Machinery Program

    SciTech Connect

    Olszewski, Mitchell

    2010-10-01

    ) develop and validate individual subsystems and components, including electric motors and PE; and (3) determine how well the components and subsystems work together in a vehicle environment or as a complete propulsion system and whether the efficiency and performance targets at the vehicle level have been achieved. The research performed under this subprogram will help remove technical and cost barriers to enable the development of technology for use in such advanced vehicles as hybrid electric vehicles (HEVs), plug-in HEVs (PHEVs), battery electric vehicles, and fuel-cell-powered automobiles that meet the goals of the VTP. A key element in making these advanced vehicles practical is providing an affordable electric traction drive system. This will require attaining weight, volume, and cost targets for the PE and electrical machines subsystems of the traction drive system. Areas of development include: (1) novel traction motor designs that result in increased power density and lower cost; (2) inverter technologies involving new topologies to achieve higher efficiency, with the ability to accommodate higher temperature environments while achieving high reliability; (3) converter concepts that use methods of reducing the component count and integrating functionality to decrease size, weight, and cost; (4) new onboard battery charging concepts that result in decreased cost and size; (5) more effective thermal control through innovative packaging technologies; and (6) integrated motor/inverter concepts. ORNL's Power Electronics and Electric Machines Research Program conducts fundamental research, evaluates hardware, and assists in the technical direction of the VTP APEEM subprogram. In this role, ORNL serves on the FreedomCAR Electrical and Electronics Technical Team, evaluates proposals for DOE, and lends its technological expertise to the direction of projects and evaluation of developing technologies. ORNL also executes specific projects for DOE. The following report

  5. Effect of tangential traction and roughness on crack initiation/propagation during rolling contact

    NASA Technical Reports Server (NTRS)

    Soda, N.; Yamamoto, T.

    1980-01-01

    Rolling fatigue tests of 0.45 percent carbon steel rollers were carried out using a four roller type rolling contact fatigue tester. Tangential traction and surface roughness of the harder mating rollers were varied and their effect was studied. The results indicate that the fatigue life decreases when fraction is applied in the same direction as that of rolling. When the direction of fraction is reversed, the life increases over that obtained with zero traction. The roughness of harder mating roller also has a marked influence on life. The smoother the mating roller, the longer the life. Microscopic observation of specimens revealed that the initiation of cracks during the early stages of life is more strongly influenced by the surface roughness, while the propagation of these cracks in the latter stages is affected mainly by the tangential traction.

  6. Some effects of grooved runway configurations on aircraft tire braking traction under flooded runway conditions

    NASA Technical Reports Server (NTRS)

    Byrdsong, T. A.

    1973-01-01

    An experimental investigation was conducted to study the effect of grooved runway configurations on aircraft tire braking traction on flooded runway surfaces. The investigation was performed, utilizing size 49 x 17, type VII, aircraft tires with an inflation pressure of 170 lb per square inch at ground speeds up to approximately 120 knots. The results of this investigation indicate that when the runway is flooded, grooved surfaces provide better braking traction than an ungrooved surface and, in general, the level of braking traction was found to improve as the tire bearing pressure was increased because of an increase in the groove area of either the surface or the tire tread. Rounding the groove edges tended to degrade the tire braking capability from that developed on the same groove configuration with sharp edges. Results also indicate that braking friction coefficients for the test tires and runway surfaces decreased as ground speed was increased because of the hydroplaning effects.

  7. [Morphologic changes in the mandibular condyle under the action of extraoral traction].

    PubMed

    Latiĭ, A A

    1989-01-01

    The experiment was performed in 29 mongrel dogs in the periods from second dentition to final occlusion formation. The mandibular traction was applied for 3, 7, 15, 30, 60 and 90 days, the restitutional period lasted for 45 days. At early stages of the traction the active cartilage and osseous tissue structuration was noted in the condylus. The late period displayed the suppression of the cartilage growth and increased ossification of cartilage zone with prevalent secondary type, atypical of the condylar cartilage. This resulted in the cartilage ossification around the dilated blood vessels and delayed primary trabeculae formation at the ossification border. With the traction released, a tendency to normal cartilage osteogenesis was evident, though the width and structure of the cartilage zone of the condylus were not fully restored.

  8. Simulation of curving behaviour under high traction in lubricated wheel-rail contacts

    NASA Astrophysics Data System (ADS)

    Arias-Cuevas, Oscar; Li, Zili; Popovici, Radu I.; Schipper, Dik J.

    2010-12-01

    Migration of the flange lubricant to the top of the high rail may compromise the traction of a rail vehicle and affect its curving behaviour. In order to simulate this possible situation, a lubrication model has been coupled to commercial multi-body dynamics software to describe the tangential formulation of the lubricated high-rail contact. Different friction levels have been adopted for the low rail to study their influence on the curving behaviour and traction. Since the creep force in the wheel-rail contact approaches saturation of the friction, the traction control unit of the rail vehicle under study has also been modelled to account for the reduction of the wheel axle torque in the presence of wheel macro-slip.

  9. Tracking traction force changes of single cells on the liquid crystal surface.

    PubMed

    Soon, Chin Fhong; Tee, Kian Sek; Youseffi, Mansour; Denyer, Morgan C T

    2015-03-01

    Cell migration is a key contributor to wound repair. This study presents findings indicating that the liquid crystal based cell traction force transducer (LCTFT) system can be used in conjunction with a bespoke cell traction force mapping (CTFM) software to monitor cell/surface traction forces from quiescent state in real time. In this study, time-lapse photo microscopy allowed cell induced deformations in liquid crystal coated substrates to be monitored and analyzed. The results indicated that the system could be used to monitor the generation of cell/surface forces in an initially quiescent cell, as it migrated over the culture substrate, via multiple points of contact between the cell and the surface. Future application of this system is the real-time assaying of the pharmacological effects of cytokines on the mechanics of cell migration. PMID:25808839

  10. Traction boundary integral equation (BIE) formulations and applications to nonplanar and multiple cracks

    NASA Astrophysics Data System (ADS)

    Cruse, Thomas A.; Novati, Giorgio

    The hypersingular Somigliana identity for the stress tensor is used as the basis for a traction boundary integral equation (BIE) suitable for numerical application to nonplanar cracks and to multiple cracks. The variety of derivations of hypersingular traction BIE formulations is reviewed and extended for this problem class. Numerical implementation is accomplished for piecewise-flat models of curved cracks, using local coordinate system integrations. A nonconforming, triangular boundary element implementation of the integral equations is given. Demonstration problems include several three-dimensional approximations to plane-strain fracture mechanics problems, for which exact or highly accurate numerical solutions exist. In all cases, the use of a piecewise-flat traction BIE implementation is shown to give excellent results.

  11. A model-based traction control strategy non-reliant on wheel slip information

    NASA Astrophysics Data System (ADS)

    Deur, Joško; Pavković, Danijel; Burgio, Gilberto; Hrovat, Davor

    2011-08-01

    A traction control system (TCS) for two-wheel-drive vehicles can conveniently be realised by means of slip control. Such a TCS is modified in this paper in order to be applicable to four-wheel-drive vehicles and anti-lock braking systems, where slip information is not readily available. A reference vehicle model is used to estimate the vehicle velocity. The reference model is excited by a saw-tooth signal in order to adapt the slip for maximum tyre traction performance. The model-based TCS is made robust to vehicle modelling errors by extending it with (i) a superimposed loop of tyre static curve gradient control or (ii) a robust switching controller based on a bi-directional saw-tooth excitation signal. The proposed traction control strategies are verified by experiments and computer simulations.

  12. Stability analysis of pressure correction schemes for the Navier–Stokes equations with traction boundary conditions

    NASA Astrophysics Data System (ADS)

    Lee, Sanghyun; Salgado, Abner J.

    2016-09-01

    We present a stability analysis for two different rotational pressure correction schemes with open and traction boundary conditions. First, we provide a stability analysis for a rotational version of the grad-div stabilized scheme of [A. Bonito, J.-L. Guermond, and S. Lee. Modified pressure-correction projection methods: Open boundary and variable time stepping. In Numerical Mathematics and Advanced Applications - ENUMATH 2013, volume 103 of Lecture Notes in Computational Science and Engineering, pages 623-631. Springer, 2015]. This scheme turns out to be unconditionally stable, provided the stabilization parameter is suitably chosen. We also establish a conditional stability result for the boundary correction scheme presented in [E. Bansch. A finite element pressure correction scheme for the Navier-Stokes equations with traction boundary condition. Comput. Methods Appl. Mech. Engrg., 279:198-211, 2014]. These results are shown by employing the equivalence between stabilized gauge Uzawa methods and rotational pressure correction schemes with traction boundary conditions.

  13. Traction Slip Ratio Control Based on Fuzzy DSMC for Independent AWD EV

    NASA Astrophysics Data System (ADS)

    Zou, Guangcai; Luo, Yugong; Li, Keqiang

    A traction slip ratio control method using fuzzy dynamical sliding mode strategy (Fuzzy DSMC) is proposed to reduce the slip ratio oscillations in the independent AWD EV traction control. The slip ratios are also accurately estimated in a new way to support this control process. Firstly in this control method, the fuzzy logic method is applied respectively to regulate the switching surface and the reaching law of DSMC with the estimated slip ratios, which are used to weaken the chattering and improve the convergence rate to some extent. Furthermore the control structure of DSMC is designed to obtain the smooth torque outputs from all independent traction motors, which are implemented in the anti-skid control for EV in the end. The mathematics analysis for the controller parameters choosing and simulation experiments show that the method can greatly avoid the drawback of control chattering occurred in the classical sliding mode control. Moreover, the robustness of systems for parameter uncertainties is also guaranteed.

  14. Tracking Traction Force Changes of Single Cells on the Liquid Crystal Surface

    PubMed Central

    Soon, Chin Fhong; Tee, Kian Sek; Youseffi, Mansour; Denyer, Morgan C. T.

    2015-01-01

    Cell migration is a key contributor to wound repair. This study presents findings indicating that the liquid crystal based cell traction force transducer (LCTFT) system can be used in conjunction with a bespoke cell traction force mapping (CTFM) software to monitor cell/surface traction forces from quiescent state in real time. In this study, time-lapse photo microscopy allowed cell induced deformations in liquid crystal coated substrates to be monitored and analyzed. The results indicated that the system could be used to monitor the generation of cell/surface forces in an initially quiescent cell, as it migrated over the culture substrate, via multiple points of contact between the cell and the surface. Future application of this system is the real-time assaying of the pharmacological effects of cytokines on the mechanics of cell migration. PMID:25808839

  15. Improved limb positioning and hip access during hip arthroscopy with articulated traction device.

    PubMed

    Mei-Dan, Omer; McConkey, Mark O; Young, David A

    2013-02-01

    Surgeons use hip arthroscopy to address intra-articular pathology of the hip. To access the central compartment, traction must be applied to the leg. Various types of equipment and techniques have been used, but many have limitations. Improved ability to assess the offending pathology is achieved with improved ability to move the hip joint in space during surgery. Dynamic assessment of femoroacetabular impingement allows the surgeon to gauge the adequacy of resection. We describe the use of an articulated traction device that allows complete surgeon control over the leg position, as well as the freedom to place the leg in virtually any position with ease, unencumbered by the mechanics of a standard traction table. This device provides the surgeon with an improved ability to dynamically assess the hip and removes some of the responsibility of the operating room staff for intraoperative leg positioning. PMID:23802095

  16. Intermittent axial wrist traction as a conservative treatment for carpal tunnel syndrome: a case series.

    PubMed

    Brunarski, David J; Kleinberg, Brian A; Wilkins, Kathryn R

    2004-09-01

    Four patients with clinical and electrodiagnostic evidence of carpal tunnel syndrome underwent intermittent axial wrist traction with a pneumatic device which applied a controlled traction force of forty to sixty pounds per square inch along the axis of the forearm. Traction cycled intermittently five seconds on and five seconds off. Treatment duration was five minutes. Patients in this study received between five and twelve treatment sessions over a three month period. All neurophysiological tests were performed at an independent site without knowledge of treatment plan before treatment commenced and then repeated after the last treatment three months later. Clinical tests were performed initially, after three months and after one year. Significant subjective improvement in all cases were accompanied by objective improvement and normalization of the nerve conduction studies.

  17. Head-Down Tilt with Balanced Traction as a Model for Simulating Spinal Acclimation to Microgravity

    NASA Technical Reports Server (NTRS)

    Ballard, R. E.; Styf, J. R.; Watenpaugh, D. E.; Fechner, K.; Haruna, Y.; Kahan, N. J.; Hargens, A. R.

    1994-01-01

    Astronauts experience total body height increases of 4 to 7 cm in microgravity. Thus, stretching of the spinal cord, nerve roots, and muscular and ligamentous tissues may be responsible for the hyperreflexia, back pain, and muscular atrophy associated with exposure to microgravity. Axial compression of the spine makes 6 deg. head-down tilt (HDT) an unsuitable model for spinal acclimation to microgravity. However, this axial compression may be counteracted by balanced traction consisting of 10% body weight (sin 6 deg. = 0.1) applied to the legs. Six healthy male subjects underwent 3 days each of 60 HDT with balanced traction and horizontal bed rest (HBR), with a 2 week recovery period between treatments. Total body and spine length, lumbar disc height, back pain, erector spinae intramuscular pressure, and ankle joint torque were measured before, during and after each treatment. Total body and spine (processes of L5 - C7) lengths increased significantly more during HDT with balanced traction (22 +/- 8 mm and 25 +/- 8 mm, respectively) than during HBR (16 +/- 4 mm and 14 +/- 9 mm, respectively). Back and leg pain were significantly greater during HDT with balanced traction than during HBR. The distance between the lower end plate of L4 and the upper endplate of S1, as measured by sonography, increased significantly in both treatments to the same degree (2.9 +/- 1.9 mm, HDT with balanced traction; 3.3 +/- 1.5 mm, HBR). Intramuscular pressure of the erector spinae muscles and maximal ankle joint torque were unaltered with both models. While neither model increased height to the magnitude observed in microgravity, HDT with balanced traction may be a better model for simulating the body lengthening and back pain experienced in microgravity.

  18. A Novel Cell Traction Force Microscopy to Study Multi-Cellular System

    PubMed Central

    Anand, Sandeep V.; Saif, Taher A.

    2014-01-01

    Traction forces exerted by adherent cells on their microenvironment can mediate many critical cellular functions. Accurate quantification of these forces is essential for mechanistic understanding of mechanotransduction. However, most existing methods of quantifying cellular forces are limited to single cells in isolation, whereas most physiological processes are inherently multi-cellular in nature where cell-cell and cell-microenvironment interactions determine the emergent properties of cell clusters. In the present study, a robust finite-element-method-based cell traction force microscopy technique is developed to estimate the traction forces produced by multiple isolated cells as well as cell clusters on soft substrates. The method accounts for the finite thickness of the substrate. Hence, cell cluster size can be larger than substrate thickness. The method allows computing the traction field from the substrate displacements within the cells' and clusters' boundaries. The displacement data outside these boundaries are not necessary. The utility of the method is demonstrated by computing the traction generated by multiple monkey kidney fibroblasts (MKF) and human colon cancerous (HCT-8) cells in close proximity, as well as by large clusters. It is found that cells act as individual contractile groups within clusters for generating traction. There may be multiple of such groups in the cluster, or the entire cluster may behave a single group. Individual cells do not form dipoles, but serve as a conduit of force (transmission lines) over long distances in the cluster. The cell-cell force can be either tensile or compressive depending on the cell-microenvironment interactions. PMID:24901766

  19. 75 FR 81659 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Affordable...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-28

    ...; Affordable Care Act Enrollment Opportunity Notice--Prohibition on Lifetime Limits ACTION: Notice. SUMMARY... Administration (EBSA) sponsored information collection request (ICR) titled, ``Affordable Care Act Enrollment... INFORMATION: The Patient Protection and Affordable Care Act (the Affordable Care Act)......

  20. 75 FR 32480 - Funding Opportunity: Affordable Care Act Medicare Beneficiary Outreach and Assistance Program...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-08

    ... HUMAN SERVICES Administration on Aging Funding Opportunity: Affordable Care Act Medicare Beneficiary...: Availability of funding opportunity announcement. Funding Opportunity Title/Program Name: Affordable Care Act... Protection and Affordable Care Act of 2010 (Affordable Care Act). Catalog of Federal Domestic...

  1. The effect of tibio-femoral traction mobilization on passive knee flexion motion impairment and pain: a case series.

    PubMed

    Maher, Sara; Creighton, Doug; Kondratek, Melodie; Krauss, John; Qu, Xianggui

    2010-03-01

    The purpose of this case series was to explore the effects of tibio-femoral (TF) manual traction on pain and passive range of motion (PROM) in individuals with unilateral motion impairment and pain in knee flexion. Thirteen participants volunteered for the study. All participants received 6 minutes of TF traction mobilization applied at end-range passive knee flexion. PROM measurements were taken before the intervention and after 2, 4, and 6 minutes of TF joint traction. Pain was measured using a visual analog scale with the TF joint at rest, at end-range passive knee flexion, during the application of joint traction, and immediately post-treatment. There were significant differences in PROM after 2 and 4 minutes of traction, with no significance noted after 4 minutes. A significant change in knee flexion of 25.9°, which exceeded the MDC(95,) was found when comparing PROM measurements pre- to final intervention. While pain did not change significantly over time, pain levels did change significantly during each treatment session. Pain significantly increased when the participant's knee was passively flexed to end range; it was reduced, although not significantly, during traction mobilization; and it significantly decreased following traction. This case series supports TF joint traction as a means of stretching shortened articular and periarticular tissues without increasing reported levels of pain during or after treatment. In addition, this is the first study documenting the temporal aspects of treatment effectiveness in motion restoration.

  2. A general protocol to afford enantioenriched linear homoprenylic amines.

    PubMed

    Bosque, Irene; Foubelo, Francisco; Gonzalez-Gomez, Jose C

    2013-11-21

    The reaction of a readily obtained chiral branched homoprenylamonium salt with a range of aldehydes, including aliphatic substrates, affords the corresponding linear isomers in good yields and enantioselectivities.

  3. Dynamic evaluation of a traction-drive joint for space telerobots

    NASA Technical Reports Server (NTRS)

    Desilva, Clarence W.; Hankins, Walter W., III

    1988-01-01

    Presented is an analysis and evaluation of a prototype traction-drive joint for robotic manipulators, developed under NASA sponsorship. A dynamic model is developed using the Lagrange formulation. Controllability, observability, dynamic stability, and response characteristics of the joint to test inputs are studied. A linear quadratic regulator (LQR) is implemented on the joint model to determine a basis for evaluating the performance of the traction-drive joint under servo control. An evaluation of the results and directions for future investigations are presented.

  4. Coordination of Flow and Traction in Migration of Amoeboid Physarum polycephalum: Model and Measurement

    NASA Astrophysics Data System (ADS)

    Lewis, Owen; Guy, Robert; Zhang, Shun; Del Alamo, Juan Carlos

    2014-11-01

    In this research, we develop a computational model of crawling Physarum based on the Immersed Boundary Method. Our model incorporates the effects of cell cytoplasm, the internal cytoskeleton and adhesions to the substrate. Cytoplasmic flows and traction stresses predicted by the model are compared to experimentally measured values obtained using simultaneous Traction Force Microscopy (TFM) and Particle Image Velocimetry (PIV). Of particular interest are stresses generated by flow and how transmission of stresses to the substrate is coordinated. We identify methods of adhesion-flow coordination which are consistent with experiments. Certain consisten coordinations are seen to be ``optimal'' with regards to crawling speed, and robust to perturbations in the extracellular environment.

  5. Parametric tests of a traction drive retrofitted to an automotive gas turbine

    NASA Technical Reports Server (NTRS)

    Rohn, D. A.; Lowenthal, S. H.; Anderson, N. E.

    1980-01-01

    The results of a test program to retrofit a high performance fixed ratio Nasvytis Multiroller Traction Drive in place of a helical gear set to a gas turbine engine are presented. Parametric tests up to a maximum engine power turbine speed of 45,500 rpm and to a power level of 11 kW were conducted. Comparisons were made to similar drives that were parametrically tested on a back-to-back test stand. The drive showed good compatibility with the gas turbine engine. Specific fuel consumption of the engine with the traction drive speed reducer installed was comparable to the original helical gearset equipped engine.

  6. Effect of combining traction and vibration on back muscles, heart rate and blood pressure.

    PubMed

    Wang, Lizhen; Zhao, Meiya; Ma, Jian; Tian, Shan; Xiang, Pin; Yao, Wei; Fan, Yubo

    2014-11-01

    Eighty-five percent of the population has experienced low back pain (LBP), which may result in decreasing muscle strength and endurance, functional capacity of the spine, and so on. Traction and vibration are commonly used to relieve the low back pain. The effect of the combing traction and vibration on back muscles, heart rate (HR) and blood pressure (BP) was investigated in this study. Thirty healthy subjects participated in 12 trials lying supine on the spine-combing bed with different tilt angle (0°, 10°, 20° and 30°) and vibration modes (along with the sagittal and coronal axis with 0 Hz, 2 Hz and 12 Hz separately). EMG was recorded during each trial. Power spectral frequency analysis was applied to evaluate muscle fatigue by the shift of median power frequency (MPF). Pulse pressure (PP) was calculated from BP. HR and PP were used to estimate the effect of the combination of traction and vibration on the cardio-vascular system. It was shown that vibration could increase HR and decrease PP. The combination of traction and vibration (2 Hz vibration along Z-axis and 12 Hz vibration along Y-axis) had no significant effect on the cardio-vascular system. The MPF of lumbar erector spinae (LES) and upper trapezius (UT) decreased significantly when the angle reached 20° under the condition of 2 Hz vibration along Z-axis compared with it of 0°. Furthermore, the MPF also decreased significantly compared with it of static mode at 20° for LES and at 30° for UT. However at 12 Hz vibration along Y-axis, the MPF had significant increase when the angle reached 20° in LES and 30° in UT compared to 0°. For LES, the MPF also had significant difference when the angle was increased from 10° to 20°. Therefore, combining 2 Hz vibration along Z-axis and traction (tilt angles that less than 20°) may to reduce muscle fatigue both for LES and UT compared with either vibration or traction alone. The combination of 12 Hz vibration along Y-axis and traction (tilt angles

  7. Multiroller traction drive speed reducer: Evaluation for automotive gas turbine engine

    NASA Technical Reports Server (NTRS)

    Rohn, D. A.; Anderson, N. E.; Loewenthal, S. H.

    1982-01-01

    Tests were conducted on a nominal 14:1 fixed-ratio Nasvytis multiroller traction drive retrofitted as the speed reducer in an automotive gas turbine engine. Power turbine speeds of 45,000 rpm and a drive output power of 102 kW (137 hp) were reached. The drive operated under both variable roller loading (proportional to torque) and fixed roller loading (automatic loading mechanism locked). The drive operated smoothly and efficiently as the engine speed reducer. Engine specific fuel consumption with the traction speed reducer was comparable to that with the original helical gearset.

  8. Income Dynamics and the Affordable Care Act

    PubMed Central

    Shore-Sheppard, Lara D

    2014-01-01

    Objective To examine the sources of family income dynamics leading to movement into and out of Medicaid expansion and subsidy eligibility under the Affordable Care Act. Data Source Survey of Income and Program Participation (SIPP): 1996, 2001, 2004, 2008 panels. Study Design Considering four broad subsidy eligibility categories for monthly Modified Adjusted Gross Income (MAGI) (<138 percent of the Federal Poverty Level [FPL], 138–250 percent FPL, 250–400 percent FPL, and >400 percent FPL), I use duration analysis to examine determinants of movements between categories over the course of a year. Data Collection/Extraction Using detailed monthly data, I determine the members of tax-filing units and calculate an approximation of MAGI at the monthly level. The analysis sample is adults ages 22–64 years. Principal Findings Incomes are highly variable within a year, particularly at the lower end of the income distribution. Employment transitions, including transitions not involving a period of nonemployment, and family structure changes strongly predict sufficient income volatility to trigger a change in subsidy category. Conclusions Income volatility arising from employment and family structure changes is likely to trigger changes in subsidy eligibility within the year, but the sources and effects of the volatility differ substantially depending on the individual's position in the income distribution. PMID:25327987

  9. Affordable underwater wireless optical communication using LEDs

    NASA Astrophysics Data System (ADS)

    Pilipenko, Vladimir; Arnon, Shlomi

    2013-09-01

    In recent years the need for high data rate underwater wireless communication (WC) has increased. Nowadays, the conventional technology for underwater communication is acoustic. However, the maximum data rate that acoustic technology can provide is a few kilobits per second. On the other hand, emerging applications such as underwater imaging, networks of sensors and swarms of underwater vehicles require much faster data rates. As a result, underwater optical WC, which can provide much higher data rates, has been proposed as an alternative means of communication. In addition to high data rates, affordable communication systems become an important feature in the development requirements. The outcome of these requirements is a new system design based on off-the-shelf components such as blue and green light emitting diodes (LEDs). This is due to the fact that LEDs offer solutions characterized by low cost, high efficiency, reliability and compactness. However, there are some challenges to be met when incorporating LEDs as part of the optical transmitter, such as low modulation rates and non linearity. In this paper, we review the main challenges facing the incorporation of LEDs as an integral part of underwater WC systems and propose some techniques to mitigate the LED limitations in order to achieve high data rate communication

  10. Affordable, Robust Ceramic Joining Technology (ARCJoint) Developed

    NASA Technical Reports Server (NTRS)

    Steele, Gynelle C.

    2001-01-01

    Affordable, Robust Ceramic Joining Technology (ARCJoint) is a method for joining high temperature- resistant ceramic pieces together, establishing joints that are strong, and allowing joining to be done in the field. This new way of joining allows complex shapes to be formed by joining together geometrically simple shapes. The joining technology at NASA is one of the enabling technologies for the application of silicon-carbide-based ceramic and composite components in demanding and high-temperature applications. The technology is being developed and tested for high-temperature propulsion parts for aerospace use. Commercially, it can be used for joining ceramic pieces used for high temperature applications in the power-generating and chemical industries, as well as in the microelectronics industry. This innovation could yield big payoffs for not only the power-generating industry but also the Silicon Valley chipmakers. This technology, which was developed at the NASA Glenn Research Center by Dr. Mrityunjay Singh, is a two-step process involving first using a paste to join together ceramic pieces and bonding them by heating the joint to 110 to 120 C for between 10 and 20 min. This makes the joint strong enough to be handled for the final joining. Then, a silicon-based substance is applied to the joint and heated to 1400 C for 10 to 15 min. The resulting joint is as strong as the original ceramic material and can withstand the same high temperatures.

  11. Robust, affordable, semi-direct Mars mission

    NASA Astrophysics Data System (ADS)

    Salotti, Jean-Marc

    2016-10-01

    A new architecture is proposed for the first manned Mars mission, based on current NASA developments (SLS and Orion), chemical propulsion for interplanetary transit, aerocapture for all vehicles, a split strategy, and a long stay on the surface. Two important choices make this architecture affordable and appropriate for the first mission. The first is splitting the Earth return vehicle into two parts that are launched separately and dock in Mars orbit. This is necessary to make aerocapture feasible and efficient, which considerably reduces mass. The second is reducing the crew to 3 astronauts. This simplifies the mission and reduces the SLS payload mass under the 45-metric ton limit for a direct TMI (trans-Mars injection) burn without LEO assembly. Only 4 SLS launches are required. The first takes the Mars ascent vehicle and in situ resource utilization systems to the planet's surface. The second takes the first part of the Earth return vehicle, the habitat, into Mars orbit. Two years later, two further SLS launches take a dual-use habitat (outbound trip and surface), Orion, and an enhanced service module to LEO, and then into Mars orbit, followed by the landing of the habitat on the surface. Transit time is demonstrated to be easily reduced to less than 6 months, with relatively low impact on propellant mass and none at all on the architecture.

  12. Broken affordances, broken objects: a TMS study.

    PubMed

    Buccino, Giovanni; Sato, Marc; Cattaneo, Luigi; Rodà, Francesca; Riggio, Lucia

    2009-12-01

    It is well known that specific components of motor programs are automatically activated when they are afforded by object related pragmatic features. Among these features the handle appears to be particularly salient for interacting with an object. The aim of this study was to test the modulation of the motor system when object features, particularly relevant for the action, like the object's handle, are violated. In order to address this issue a TMS paradigm was used in which familiar objects with a whole or broken handle, positioned to the right or to the left, were centrally presented. A control condition was also included in which a symbol ('#' character) was shown in the right or in the left visual field. Participants had to watch stimuli carefully. The left hemisphere hand motor area was magnetically stimulated 200 ms after stimulus presentation. Results showed that MEP areas were larger when the handle was located to the right side consistent with the visuomotor role of this feature, but only when the handle was complete. The present data (1) suggest a more active role of the dorsal stream in building up object knowledge and (2) allow one to rule out the role of any asymmetrical aspect of an object in motor coding. PMID:19615389

  13. Partnerships for affordable and equitable disaster insurance

    NASA Astrophysics Data System (ADS)

    Mysiak, J.; Pérez-Blanco, C. D.

    2015-08-01

    Extreme events are becoming more frequent and intense, inflating the economic damages and social hardship set-off by natural catastrophes. Amidst budgetary cuts, there is a growing concern on societies' ability to design solvent disaster recovery strategies, while addressing equity and affordability concerns. The participation of private sector along with public one through Public-Private Partnerships (PPPs) has gained on importance as a means to address these seemingly conflicting objectives through the provision of (catastrophic) natural hazard insurance. This is the case of many OECD countries, notably some EU Member States such as the United Kingdom and Spain. The EU legislator has adapted to this new scenario and recently produced major reforms in the legislation and regulation that govern the framework in which PPPs for (catastrophic) natural hazard insurance develop. This paper has a dual objective: (1) review the complex legal background that rules the provision of insurance against natural catastrophes in the EU after these major reforms, (2) assess the implications of the reforms and offer concise Policy Guiding Principles.

  14. Scaling affordances for human reach actions.

    PubMed

    Choi, Hyeg Joo; Mark, Leonard S

    2004-12-01

    A methodology developed by Cesari and Newell [Cesari, P., & Newell, K. M. (1999). The scaling of human grip configuration. Journal of Experimental Psychology: Human Perception and Performance 25, 927-935; Cesari, P., & Newell, K. M. (2000). The body-scaling of grip configurations in children aged 6-12 years. Developmental Psychobiology 36, 301-310] was used to delineate the roles of an object's weight (W) and distance (D) as well as the actor's strength (S) in determining the macroscopic action used to reach for the object. Participants reached for objects of five different weights placed at 10 distances. The findings of a single discriminant analysis revealed that when object weight is scaled in terms of each individual's strength and reach distance is scaled in terms of each individual's maximum-seated reach distance, a single discriminant analysis was able to predict 90% of the reach modes used by both men and women. The result of the discriminant analysis was used to construct a body-scaled equation, K=lnD+ln(W/S)/36, similar in form to the one derived by Cesari and Newell, accurately predicted the reach action used. Our findings indicate that Cesari and Newell's method can identify a complex relationship between geometric and dynamic constraints that determine the affordances for different reach actions. PMID:15664673

  15. Empathy and the responsiveness to social affordances.

    PubMed

    Kiverstein, Julian

    2015-11-01

    The direct perception theory of empathy claims that we can immediately experience a person's state of mind. I can see for instance that my neighbour is angry with me in his bodily countenance. I develop a version of the direct perception theory of empathy which takes this perceptual capacity to depend upon recognising in what way the other person is responsive to the affordances the environment provides. By recognising which possibilities for action are relevant to a person, I can thereby understand something about the meaning they give to the world. I come to share something of their perspective on the world, and this allows me to grasp based on my perception of them something about their current state of mind. I argue that shared affect plays a central role in this perceptual capacity. Shared affect allows me to orient my attention to possibilities for action that matter to the other person. I end by briefly discuss the implications of this view of empathy for the disturbances in so-called "cognitive empathy" that are found in people diagnosed with autism spectrum disorder.

  16. Traction characteristics of high-temperature powder-lubricated ceramics (Si3N4/alpha SiC)

    SciTech Connect

    Heshmat, Hooshang; Dill, J.F. )

    1992-04-01

    As part of a development program for a high-temperature, dry-lubricated bearing technology and lubricant system, a high-speed high-temperature disk-on-disk tribometer was utilized and a matrix of traction data covering a range of load, speed, and temperature was obtained. The influence of dry powder lubricants, TiO2 and MoS2, on the traction coefficients between two ceramic materials, Si3N4 and SiC, was investigated. The results of this investigation are characteristic curves for the traction coefficient vs the slide/roll ratio with dry powders which are reminiscent of fluids, and the observation of dry powder lubricants' lower traction coefficients and wear. Measured tractions are found to be a strong function of powder-lubricant type, and values decrease moderately with slide-to-roll ration and load. The data show a weak sensitivity to temperature. 9 refs.

  17. Role of Electrical Activity in Promoting Neural Repair

    PubMed Central

    Goldberg, Jeffrey L.

    2012-01-01

    The nervous system communicates in a language of electrical activities. The motivation to replace function lost through injury or disease through electrical prostheses has gained traction through steady advances in basic and translational science addressing the interface between electrical prostheses and the nervous system. Recent experiments suggest that electrical activity, signaling through specific molecular pathways, promotes neuronal survival and regeneration. Such data suggests that electrical prostheses, in addition to replacing lost function, may slow underlying degenerative disease or induce regenerative response. Here we review these data with a focus on retinal neurons, and discuss current efforts to translate this effect of electrical activity into clinically applicable treatments. PMID:22342908

  18. Computed tomography arthrography with traction in the human hip for three-dimensional reconstruction of cartilage and the acetabular labrum

    PubMed Central

    Henak, C.R.; Abraham, C.L.; Peters, C.L.; Sanders, R.K.; Weiss, J.A.; Anderson, A.E.

    2014-01-01

    AIM To develop and demonstrate the efficacy of a computed tomography arthrography (CTA) protocol for the hip that enables accurate three-dimensional reconstructions of cartilage and excellent visualization of the acetabular labrum. MATERIALS AND METHODS Ninety-three subjects were imaged (104 scans); 68 subjects with abnormal anatomy, 11 patients after periacetabular osteotomy surgery, and 25 subjects with normal anatomy. Fifteen to 25 ml of contrast agent diluted with lidocaine was injected using a lateral oblique approach. A Hare traction splint applied traction during CT. The association between traction force and intra-articular joint space was assessed qualitatively under fluoroscopy. Cartilage geometry was reconstructed from the CTA images for 30 subjects; the maximum joint space under traction was measured. RESULTS Using the Hare traction splint, the intra-articular space and boundaries of cartilage could be clearly delineated throughout the joint; the acetabular labrum was also visible. Dysplastic hips required less traction (~5 kg) than normal and retroverted hips required (>10 kg) to separate the cartilage. An increase in traction force produced a corresponding widening of the intra-articular joint space. Under traction, the maximum width of the intra-articular joint space during CT ranged from 0.98–6.7 mm (2.46 ± 1.16 mm). CONCLUSIONS When applied to subjects with normal and abnormal hip anatomy, the CTA protocol presented yields clear delineation of the cartilage and the acetabular labrum. Use of a Hare traction splint provides a simple, cost-effective method to widen the intra-articular joint space during CT, and provides flexibility to vary the traction as required. PMID:25070373

  19. Ground Processing Affordability for Space Vehicles

    NASA Technical Reports Server (NTRS)

    Ingalls, John; Scott, Russell

    2011-01-01

    Launch vehicles and most of their payloads spend the majority of their time on the ground. The cost of ground operations is very high. So, why so often is so little attention given to ground processing during development? The current global space industry and economic environment are driving more need for efficiencies to save time and money. Affordability and sustainability are more important now than ever. We can not continue to treat space vehicles as mere science projects. More RLV's (Reusable Launch Vehicles) are being developed for the gains of reusability which are not available for ELV's (Expendable Launch Vehicles). More human-rated vehicles are being developed, with the retirement of the Space Shuttles, and for a new global space race, yet these cost more than the many unmanned vehicles of today. We can learn many lessons on affordability from RLV's. DFO (Design for Operations) considers ground operations during design, development, and manufacturing-before the first flight. This is often minimized for space vehicles, but is very important. Vehicles are designed for launch and mission operations. You will not be able to do it again if it is too slow or costly to get there. Many times, technology changes faster than space products such that what is launched includes outdated features, thus reducing competitiveness. Ground operations must be considered for the full product Lifecycle, from concept to retirement. Once manufactured, launch vehicles along with their payloads and launch systems require a long path of processing before launch. Initial assembly and testing always discover problems to address. A solid integration program is essential to minimize these impacts, as was seen in the Constellation Ares I-X test rocket. For RLV's, landing/recovery and post-flight turnaround activities are performed. Multi-use vehicles require reconfiguration. MRO (Maintenance, Repair, and Overhaul) must be well-planned--- even for the unplanned problems. Defect limits and

  20. Commercial Platforms Allow Affordable Space Research

    NASA Technical Reports Server (NTRS)

    2013-01-01

    At an altitude of about 240 miles, its orbital path carries it over 90 percent of the Earth s population. It circles the Earth in continuous free fall; its crew of six and one Robonaut pass the days, experiencing 16 sunrises and 16 sunsets every 24 hours, in microgravity, an environment in which everything from bodily functions to the physical behavior of materials changes drastically from what is common on the ground. Outside its shielded confines, temperatures cycle from one extreme to the other, radiation is rampant, and atomic oxygen corrodes everything it touches. A unique feat of engineering, the International Space Station (ISS) also represents the most remarkable platform for scientific research ever devised. In 2005, anticipating the space station s potential for NASA and non-NASA scientists alike, the NASA Authorization Act designated the US segment of the ISS as a national laboratory, instructing the Agency to "increase the utilization of the ISS by other Federal entities and the private sector." With the ISS set to maintain operations through at least 2020, the station offers an unprecedented long-term access to space conditions, enabling research not previously possible. "There will be new drug discoveries, new pharmaceuticals, a better understanding of how we affect the planet and how we can maintain it," says Marybeth Edeen, the ISS National Laboratory manager, based at Johnson Space Center. The ISS, she says, represents a major example of the government s role in making such advancements possible. "The government is key in that researchers cannot afford to build the kind of infrastructure that the government can provide. But we then have to make that infrastructure available at a reasonable cost." Enter Jeff Manber, who saw in the ISS National Lab an extraordinary opportunity to advance science, education, and business in ways never before seen.

  1. Affordable Space Tourism: SpaceStationSim

    NASA Technical Reports Server (NTRS)

    2006-01-01

    For over 5 years, people have been living and working in space on the International Space Station (ISS), a state-of-the-art laboratory complex orbiting high above the Earth. Offering a large, sustained microgravity environment that cannot be duplicated on Earth, the ISS furthers humankind s knowledge of science and how the body functions for extended periods of time in space all of which will prove vital on long-duration missions to Mars. On-orbit construction of the station began in November 1998, with the launch of the Russian Zarya Control Module, which provided battery power and fuel storage. This module was followed by additional components and supplies over the course of several months. In November 2000, the first ISS Expedition crew moved in. Since then, the ISS has continued to change and evolve. The space station is currently 240 feet wide, measured across the solar arrays, and 171 feet long, from the NASA Destiny Laboratory to the Russian Zvezda Habitation Module. It is 90 feet tall, and it weighs approximately 404,000 pounds. Crews inhabit a living space of about 15,000 cubic feet. To date, 90 scientific investigations have been conducted on the space station. New results from space station research, from basic science to exploration research, are being published each month, and more breakthroughs are likely to come. It is not all work on the space station, though. The orbiting home affords many of the comforts one finds on Earth. There is a weightless "weight room" and even a musical keyboard alongside research facilities. Holidays are observed, and with them, traditional foods such as turkey and cobbler are eaten, with lemonade to wash them down

  2. Burros: Simple, affordable, effective space transportation

    SciTech Connect

    Canavan, G.H.

    1992-05-01

    This note argues that space is the best place to put not only the sensors, but also the SBIs Spare Based Interceptors and DEWs Directed-Energy Weapons needed to address long-range, intra- and inter-theater missiles efficiently. There are real threats; they are likely to worsen. Ground-based defenses cannot handle them all affordably. Mixes are generally appropriate. There is a role for SBIs, but it doesn't appear to require all of the capabilities built into the current SBIs at the outset. The SBIs that are needed now could be no more than cheap burros that were amenable to joint development and robust command for the protection of all. Their deployment for (GPALs) Global Protection Against Limited Strikes should not adversely impact the arms control or crisis stability of the strategic balance with the Soviet Union in any rational, concrete calculus, including that used by the Soviet Union. Deployment at low latitudes should give them adequate capability against theater launches but none against Soviet (ICMBs) International Ballist Missiles and only marginal, residual impact on (SLBMs) Submarine-Launched Ballistics Missiles. They should not either leave hot production capability of anything threatening or provoke untoward responses. We have a hot production line on Chevrolets that would pose more of a threat to the Soviet Union. Their inability to overcome even crude Soviet countermeasures would be an asset in this light. A companion effort could develop the brilliant eyes needed to guide them. A similar logic is possible with DEWs, but they are less developed and hence less at issue. 57 refs.

  3. Burros: Simple, affordable, effective space transportation

    SciTech Connect

    Canavan, G.H.

    1992-05-01

    This note argues that space is the best place to put not only the sensors, but also the SBIs Spare Based Interceptors and DEWs Directed-Energy Weapons needed to address long-range, intra- and inter-theater missiles efficiently. There are real threats; they are likely to worsen. Ground-based defenses cannot handle them all affordably. Mixes are generally appropriate. There is a role for SBIs, but it doesn`t appear to require all of the capabilities built into the current SBIs at the outset. The SBIs that are needed now could be no more than cheap burros that were amenable to joint development and robust command for the protection of all. Their deployment for (GPALs) Global Protection Against Limited Strikes should not adversely impact the arms control or crisis stability of the strategic balance with the Soviet Union in any rational, concrete calculus, including that used by the Soviet Union. Deployment at low latitudes should give them adequate capability against theater launches but none against Soviet (ICMBs) International Ballist Missiles and only marginal, residual impact on (SLBMs) Submarine-Launched Ballistics Missiles. They should not either leave hot production capability of anything threatening or provoke untoward responses. We have a hot production line on Chevrolets that would pose more of a threat to the Soviet Union. Their inability to overcome even crude Soviet countermeasures would be an asset in this light. A companion effort could develop the brilliant eyes needed to guide them. A similar logic is possible with DEWs, but they are less developed and hence less at issue. 57 refs.

  4. Biopolymer-reinforced synthetic granular nanocomposites for affordable point-of-use water purification.

    PubMed

    Sankar, Mohan Udhaya; Aigal, Sahaja; Maliyekkal, Shihabudheen M; Chaudhary, Amrita; Anshup; Kumar, Avula Anil; Chaudhari, Kamalesh; Pradeep, Thalappil

    2013-05-21

    Creation of affordable materials for constant release of silver ions in water is one of the most promising ways to provide microbially safe drinking water for all. Combining the capacity of diverse nanocomposites to scavenge toxic species such as arsenic, lead, and other contaminants along with the above capability can result in affordable, all-inclusive drinking water purifiers that can function without electricity. The critical problem in achieving this is the synthesis of stable materials that can release silver ions continuously in the presence of complex species usually present in drinking water that deposit and cause scaling on nanomaterial surfaces. Here we show that such constant release materials can be synthesized in a simple and effective fashion in water itself without the use of electrical power. The nanocomposite exhibits river sand-like properties, such as higher shear strength in loose and wet forms. These materials have been used to develop an affordable water purifier to deliver clean drinking water at US $2.5/y per family. The ability to prepare nanostructured compositions at near ambient temperature has wide relevance for adsorption-based water purification. PMID:23650396

  5. An integrated approach to low-income energy affordability for a restructured world

    SciTech Connect

    Hamilton, B.; Carroll, D.; Adams, B.; Ringhof, S.

    1998-07-01

    In the context of retail electric competition, various mechanisms have been proposed to address threats to low-income energy affordability. Most proposals include the use of ratepayer for (a) low-income bill payment support (e.g., rate discounts) and/or (b) energy efficiency programs specifically designated for low-income customers. An integrated approach to both energy efficiency and low-income bill payment is being tested in New Jersey. The program specifically targets payment-troubled customers and those with the lowest incomes. It combines a three-part approach to energy affordability: (1) deep and comprehensive gas and electric efficiency measures; (2) extensive customer energy education, with the goals of both (a) empowering participants with the skills and knowledge to gain control of their energy situation and (b) securing action commitment that the customer carries out as a partner to save energy and lower their utility bills; and (3) an affordable payment plan which includes extended payment of arrearages, partial arrearage forgiveness, and a bill discount for those in the lowest income tier who maintain their partnership obligations. This paper describes the E-Team Partners program design, presents preliminary impact evaluation results for the first 7,000 participants, and discusses the attributes of this model in a restructured environment.

  6. Biopolymer-reinforced synthetic granular nanocomposites for affordable point-of-use water purification

    PubMed Central

    Sankar, Mohan Udhaya; Aigal, Sahaja; Maliyekkal, Shihabudheen M.; Chaudhary, Amrita; Anshup; Kumar, Avula Anil; Chaudhari, Kamalesh; Pradeep, Thalappil

    2013-01-01

    Creation of affordable materials for constant release of silver ions in water is one of the most promising ways to provide microbially safe drinking water for all. Combining the capacity of diverse nanocomposites to scavenge toxic species such as arsenic, lead, and other contaminants along with the above capability can result in affordable, all-inclusive drinking water purifiers that can function without electricity. The critical problem in achieving this is the synthesis of stable materials that can release silver ions continuously in the presence of complex species usually present in drinking water that deposit and cause scaling on nanomaterial surfaces. Here we show that such constant release materials can be synthesized in a simple and effective fashion in water itself without the use of electrical power. The nanocomposite exhibits river sand-like properties, such as higher shear strength in loose and wet forms. These materials have been used to develop an affordable water purifier to deliver clean drinking water at US $2.5/y per family. The ability to prepare nanostructured compositions at near ambient temperature has wide relevance for adsorption-based water purification. PMID:23650396

  7. Biopolymer-reinforced synthetic granular nanocomposites for affordable point-of-use water purification.

    PubMed

    Sankar, Mohan Udhaya; Aigal, Sahaja; Maliyekkal, Shihabudheen M; Chaudhary, Amrita; Anshup; Kumar, Avula Anil; Chaudhari, Kamalesh; Pradeep, Thalappil

    2013-05-21

    Creation of affordable materials for constant release of silver ions in water is one of the most promising ways to provide microbially safe drinking water for all. Combining the capacity of diverse nanocomposites to scavenge toxic species such as arsenic, lead, and other contaminants along with the above capability can result in affordable, all-inclusive drinking water purifiers that can function without electricity. The critical problem in achieving this is the synthesis of stable materials that can release silver ions continuously in the presence of complex species usually present in drinking water that deposit and cause scaling on nanomaterial surfaces. Here we show that such constant release materials can be synthesized in a simple and effective fashion in water itself without the use of electrical power. The nanocomposite exhibits river sand-like properties, such as higher shear strength in loose and wet forms. These materials have been used to develop an affordable water purifier to deliver clean drinking water at US $2.5/y per family. The ability to prepare nanostructured compositions at near ambient temperature has wide relevance for adsorption-based water purification.

  8. Affordance Analysis--Matching Learning Tasks with Learning Technologies

    ERIC Educational Resources Information Center

    Bower, Matt

    2008-01-01

    This article presents a design methodology for matching learning tasks with learning technologies. First a working definition of "affordances" is provided based on the need to describe the action potentials of the technologies (utility). Categories of affordances are then proposed to provide a framework for analysis. Following this, a methodology…

  9. One Hand, Two Objects: Emergence of Affordance in Contexts

    ERIC Educational Resources Information Center

    Borghi, Anna M.; Flumini, Andrea; Natraj, Nikhilesh; Wheaton, Lewis A.

    2012-01-01

    Studies on affordances typically focus on single objects. We investigated whether affordances are modulated by the context, defined by the relation between two objects and a hand. Participants were presented with pictures displaying two manipulable objects linked by a functional (knife-butter), a spatial (knife-coffee mug), or by no relation. They…

  10. The Influence of Affordability in Strategic Enrollment Management

    ERIC Educational Resources Information Center

    Pugh, Susan L.; Thompson, Roger J.

    2008-01-01

    In state houses around the country, one of the common higher education themes is affordability. As tuition costs have increased at rates exceeding that of inflation, students and families have pressed their legislative representatives to examine these increases. Affordability is a term used by various constituent groups, and its definition varies…

  11. Nurturing Opportunities for Educational Leadership: How Affordance and Leadership Interconnect

    ERIC Educational Resources Information Center

    Margolin, Ilana

    2013-01-01

    This qualitative ethnographic study focused on the affordances that facilitated the emergence of leadership, capturing a range of perspectives on leadership and leadership development of four groups: district superintendents; teacher-educators; mentor-teachers and graduates. The term "affordances" implies a reciprocal relationship…

  12. 24 CFR 1000.101 - What is affordable housing?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false What is affordable housing? 1000.101 Section 1000.101 Housing and Urban Development REGULATIONS RELATING TO HOUSING AND URBAN... URBAN DEVELOPMENT NATIVE AMERICAN HOUSING ACTIVITIES Affordable Housing Activities § 1000.101 What...

  13. 24 CFR 1000.101 - What is affordable housing?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false What is affordable housing? 1000.101 Section 1000.101 Housing and Urban Development Regulations Relating to Housing and Urban... URBAN DEVELOPMENT NATIVE AMERICAN HOUSING ACTIVITIES Affordable Housing Activities § 1000.101 What...

  14. 24 CFR 1006.20 - Grants for affordable housing activities.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... URBAN DEVELOPMENT NATIVE HAWAIIAN HOUSING BLOCK GRANT PROGRAM General § 1006.20 Grants for affordable housing activities. (a) Annual grant. Each fiscal year, HUD will make a grant (to the extent that amounts... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false Grants for affordable...

  15. 24 CFR 1006.20 - Grants for affordable housing activities.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... URBAN DEVELOPMENT NATIVE HAWAIIAN HOUSING BLOCK GRANT PROGRAM General § 1006.20 Grants for affordable housing activities. (a) Annual grant. Each fiscal year, HUD will make a grant (to the extent that amounts... 24 Housing and Urban Development 4 2012-04-01 2012-04-01 false Grants for affordable...

  16. 24 CFR 1006.20 - Grants for affordable housing activities.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... URBAN DEVELOPMENT NATIVE HAWAIIAN HOUSING BLOCK GRANT PROGRAM General § 1006.20 Grants for affordable housing activities. (a) Annual grant. Each fiscal year, HUD will make a grant (to the extent that amounts... 24 Housing and Urban Development 4 2014-04-01 2014-04-01 false Grants for affordable...

  17. 24 CFR 1006.20 - Grants for affordable housing activities.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... URBAN DEVELOPMENT NATIVE HAWAIIAN HOUSING BLOCK GRANT PROGRAM General § 1006.20 Grants for affordable housing activities. (a) Annual grant. Each fiscal year, HUD will make a grant (to the extent that amounts... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Grants for affordable...

  18. An Affordability Comparison Tool (ACT) for Space Transportation

    NASA Technical Reports Server (NTRS)

    McCleskey, C. M.; Bollo, T. R.; Garcia, J. L.

    2012-01-01

    NASA bas recently emphasized the importance of affordability for Commercial Crew Development Program (CCDP), Space Launch Systems (SLS) and Multi-Purpose Crew Vehicle (MPCV). System architects and designers are challenged to come up with architectures and designs that do not bust the budget. This paper describes the Affordability Comparison Tool (ACT) analyzes different systems or architecture configurations for affordability that allows for a comparison of: total life cycle cost; annual recurring costs, affordability figures-of-merit, such as cost per pound, cost per seat, and cost per flight, as well as productivity measures, such as payload throughput. Although ACT is not a deterministic model, the paper develops algorithms and parametric factors that use characteristics of the architectures or systems being compared to produce important system outcomes (figures-of-merit). Example applications of outcome figures-of-merit are also documented to provide the designer with information on the relative affordability and productivity of different space transportation applications.

  19. A simple and effective traction device for laparoscopic formation of a neovagina using the Vecchietti technique.

    PubMed

    Oliveira, Marco Aurelio Pinho; Kano, Adriana Emma Uzelac; Melki, Luiz Augusto Henrique; Lasmar, Ricardo Bassil; de Oliveira, Hildoberto Carneiro

    2008-01-01

    We sought to present a simple new traction device that was used with success in 4 cases of laparoscopic creation of a neovagina using a modified Vecchietti technique. Four patients were treated with laparoscopic creation of a neovagina. All women had Rokitansky-Küster-Hauser syndrome and no more than a 1-cm vestibule dimple. A 3-cm diameter and 10-cm long plastic tube (mold) was used for traction. We developed 2 independent wood traction devices. They were based on tuning pegs of a guitar. The 1-cm demarcation in the external face of the mold allowed easy observation of the effects of traction. The patients were hospitalized from 7 to 10 days and the postoperative courses were uneventful. One patient was lost after 3 months of follow-up. After a year, the other 3 patients were having intercourse and were satisfied with the results. The laparoscopic technique has several advantages: it does not need grafts, it does not need a dissection of the space between the bladder and the rectum, it uses the mucous membrane of the vestibular area, the time of hospitalization is relatively short, and it possesses good long-term results. PMID:18567542

  20. Traction and nonequilibrium phase behavior of confined sheared liquids at high pressure

    NASA Astrophysics Data System (ADS)

    Gattinoni, Chiara; Heyes, David M.; Lorenz, Christian D.; Dini, Daniele

    2013-11-01

    Nonequilibrium molecular dynamics simulations of confined model liquids under pressure and sheared by the relative sliding of the boundary walls have been carried out. The relationship between the time-dependent traction coefficient, μ(t), and the state of internal structure of the film is followed from commencement of shear for various control parameters, such as applied load, global shear rate, and solid-liquid atom interaction parameters. Phase diagrams, velocity and temperature profiles, and traction coefficient diagrams are analyzed for pure Lennard-Jones (LJ) liquids and a binary LJ mixture. A single component LJ liquid is found to form semicrystalline arrangements with high-traction coefficients, and stick-slip behavior is observed for high pressures and low-shear velocities, which is shown to involve periodic deformation and stress release of the wall atoms and slip in the solid-liquid boundary region. A binary mixture, which discourages crystallization, gives a more classical tribological response with the larger atoms preferentially adsorbing commensurate with the wall. The results obtained are analyzed in the context of tribology: the binary mixture behaves like a typical lubricant, whereas the monatomic system behaves like a traction fluid. It is discussed how this type of simulation can give insights on the tribological behavior of realistic systems.

  1. Cross talk between matrix elasticity and mechanical force regulates myoblast traction dynamics.

    PubMed

    Al-Rekabi, Zeinab; Pelling, Andrew E

    2013-12-01

    Growing evidence suggests that critical cellular processes are profoundly influenced by the cross talk between extracellular nanomechanical forces and the material properties of the cellular microenvironment. Although many studies have examined either the effect of nanomechanical forces or the material properties of the microenvironment on biological processes, few have investigated the influence of both. Here, we performed simultaneous atomic force microscopy and traction force microscopy to demonstrate that muscle precursor cells (myoblasts) rapidly generate a significant increase in traction when stimulated with a local 10 nN force. Cells were cultured and nanomechanically stimulated on hydrogel substrates with controllable local elastic moduli varying from ~16-89 kPa, as confirmed with atomic force microscopy. Importantly, cellular traction dynamics in response to nanomechanical stimulation only occurred on substrates that were similar to the elasticity of working muscle tissue (~64-89 kPa) as opposed to substrates mimicking resting tissue (~16-51 kPa). The traction response was also transient, occurring within 30 s, and dissipating by 60 s, during constant nanomechanical stimulation. The observed biophysical dynamics are very much dependent on rho-kinase and myosin-II activity and likely contribute to the physiology of these cells. Our results demonstrate the fundamental ability of cells to integrate nanoscale information in the cellular microenvironment, such as nanomechanical forces and substrate mechanics, during the process of mechanotransduction.

  2. 76 FR 2309 - Consumer Information Regulations; Fees for Use of Traction Skid Pads

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-13

    ... updating the fees currently charged for use of the traction skid pads at NHTSA's San Angelo Test Facility, formerly called the Uniform Tire Quality Grading Test Facility, in San Angelo, Texas and by eliminating... skid pads are located at NHTSA's San Angelo Test Facility. 49 CFR 575.104, App. B. In addition to...

  3. Improved-throughput traction microscopy based on fluorescence micropattern for manual microscopy.

    PubMed

    Liu, Kai; Yuan, Yuan; Huang, Jianyong; Wei, Qiong; Pang, Mingshu; Xiong, Chunyang; Fang, Jing

    2013-01-01

    Traction force microscopy (TFM) is a quantitative technique for measuring cellular traction force, which is important in understanding cellular mechanotransduction processes. Traditional TFM has a significant limitation in that it has a low measurement throughput, commonly one per TFM dish, due to a lack of cell position information. To obtain enough cellular traction force data, an onerous workload is required including numerous TFM dish preparations and heavy cell-seeding activities, creating further difficulty in achieving identical experimental conditions among batches. In this paper, we present an improved-throughput TFM method using the well-developed microcontact printing technique and chemical modifications of linking microbeads to the gel surface to address these limitations. Chemically linking the microbeads to the gel surface has no significant influence on cell proliferation, morphology, cytoskeleton, and adhesion. Multiple pairs of force loaded and null force fluorescence images can be easily acquired by means of manual microscope with the aid of a fluorescence micropattern made by microcontact printing. Furthermore, keeping the micropattern separate from cells by using gels effectively eliminates the potential negative effect of the micropattern on the cells. This novel design greatly improves the analysis throughput of traditional TFM from one to at least twenty cells per petri dish without losing unique advantages, including a high spatial resolution of traction measurements. This newly developed method will boost the investigation of cell-matrix mechanical interactions.

  4. ["Microband F" extraoral traction appliance. Antero-posterior symmetry and asymmetry].

    PubMed

    Fotis, V; Basarelli, V

    1991-01-01

    The Authors describe a new appliance for monolateral asymmetric and/or bilateral symmetric extraoral anterior tractions. This new device doesn't need chin rest; it is specifically suggested for patients suffering from TMJ dysfunctions; from the esthetic point of view it is well accepted by patients.

  5. Effect of starvation on film thickness and traction under elastohydrodynamic rolling and sliding conditions

    NASA Technical Reports Server (NTRS)

    Wedeven, L. D.

    1975-01-01

    Traction measurements under starved elastohydrodynamic conditions were obtained for a point-contact geometry. Simultaneous measurements of the film thickness and the location of the inlet lubricant boundary were made. Optical interferometry was used to measure film thickness. The thickness of a starved film for combined rolling and sliding conditions varies with the location of the inlet boundary in the same way as previously found for pure rolling conditions. When the fluid velocity distribution is calculated in the inlet region by a Reynolds lubrication analysis, backflow is seen to occur over a portion of the inlet region. Backflow is essential for the establishment of a flooded condition. The location of certain fluid velocity conditions within the inlet region, as suggested in the literature, does not adequately describe the onset of starvation. For the same slide-roll ratio a starved film was observed to possess greater traction than a flooded film. Traction measurements under starved conditions were also compared with those under flooded conditions for equivalent shear rates in the Hertzian region. When the shear rates within the Hertzian region were low and the film was severely starved, the measured tractions were lower than expected. This may be due to large shear stresses developed by the large pressure gradients that are generated in the inlet region when it is severely starved.

  6. Defining Strong State Accountability Systems: How Can Better Standards Gain Greater Traction? A First Look

    ERIC Educational Resources Information Center

    Reed, Eileen; Scull, Janie; Slicker, Gerilyn; Winkler, Amber M.

    2012-01-01

    Rigorous standards and aligned assessments are vital tools for boosting education outcomes but they have little traction without strong accountability systems that attach consequences to performance. In this pilot study, Eileen Reed, Janie Scull, Gerilyn Slicker, and Amber Winkler lay out the essential features of such accountability systems,…

  7. [Therapeutic Options in Vitreomacular Traction With or Without a Macular Hole].

    PubMed

    Maier, M; Abraham, S; Frank, C; Lohmann, C P; Feucht, N

    2016-05-01

    Treatment is usually indicated for symptomatic vitreomacular traction (VMT) with or without a full thickness macular hole (FTMH) and without spontaneous resolution. Ultrastructural parameters are evaluated by SD-OCT, in order to classify the vitreoretinal interface and to estimate the success rate of treatment. The resolution rate after therapy with intravitreal Jetrea® (Ocriplasmin) is high (up to 70 %) in patients with symptomatic focal vitreomacular traction (≤ 1500 µm) with or without a macular hole (≤ 250 µm) and with no epiretinal membrane (ERM), but depends on the exact baseline analysis. All other patients with idiopathic traction retinopathy should be treated by minimal invasive pars plana vitrectomy (MIVI). Vitreoretinal surgery effectively removes traction and gives a high closure rate of a full thickness macular hole (FTMH, 90 to 100 %). It is now a very safe procedure with few side effects. Despite a low risk profile (cataract, retinal tear etc.) the indication for surgery needs to take the safety profile into account. Therefore vitrectomy is only indicated in symptomatic patients complaining of blurred vision, VA reduction and metamorphopsia. Vitrectomy is also indicated in patients whose treatment by pharmacologic vitreolysis has failed. PMID:27187883

  8. Cross talk between matrix elasticity and mechanical force regulates myoblast traction dynamics

    NASA Astrophysics Data System (ADS)

    Al-Rekabi, Zeinab; Pelling, Andrew E.

    2013-12-01

    Growing evidence suggests that critical cellular processes are profoundly influenced by the cross talk between extracellular nanomechanical forces and the material properties of the cellular microenvironment. Although many studies have examined either the effect of nanomechanical forces or the material properties of the microenvironment on biological processes, few have investigated the influence of both. Here, we performed simultaneous atomic force microscopy and traction force microscopy to demonstrate that muscle precursor cells (myoblasts) rapidly generate a significant increase in traction when stimulated with a local 10 nN force. Cells were cultured and nanomechanically stimulated on hydrogel substrates with controllable local elastic moduli varying from ˜16-89 kPa, as confirmed with atomic force microscopy. Importantly, cellular traction dynamics in response to nanomechanical stimulation only occurred on substrates that were similar to the elasticity of working muscle tissue (˜64-89 kPa) as opposed to substrates mimicking resting tissue (˜16-51 kPa). The traction response was also transient, occurring within 30 s, and dissipating by 60 s, during constant nanomechanical stimulation. The observed biophysical dynamics are very much dependent on rho-kinase and myosin-II activity and likely contribute to the physiology of these cells. Our results demonstrate the fundamental ability of cells to integrate nanoscale information in the cellular microenvironment, such as nanomechanical forces and substrate mechanics, during the process of mechanotransduction.

  9. FY 2005 Oak Ridge National Laboratory Annual Progress Report for the Power Electronics and Electric Machinery Program

    SciTech Connect

    Olszewski, M

    2005-11-22

    component research and development activities; (2) Develop and validate individual subsystems and components, including electric motors, emission control devices, battery systems, power electronics, accessories, and devices to reduce parasitic losses; and (3) Determine how well the components and subsystems work together in a vehicle environment or as a complete propulsion system and whether the efficiency and performance targets at the vehicle level have been achieved. The research performed under the Vehicle Systems subprogram will help remove technical and cost barriers to enable technology for use in such advanced vehicles as hybrid and fuel-cell-powered automobiles that meet the goals of the FreedomCAR Program. A key element in making hybrid electric vehicles practical is providing an affordable electric traction drive system. This will require attaining weight, volume, and cost targets for the power electronics and electrical machines subsystems of the traction drive system. Areas of development include: (1) Novel traction motor designs that result in increased power density and lower cost; (2) Inverter technologies involving new topologies to achieve higher efficiency and the ability to accommodate higher-temperature environments; (3) Converter concepts that employ means of reducing the component count and integrating functionality to decrease size, weight, and cost; (4) More effective thermal control and packaging technologies; and (5) Integrated motor/inverter concepts. The Oak Ridge National Laboratory's (ORNL's) Power Electronics and Electric Machinery Research Center conducts fundamental research, evaluates hardware, and assists in the technical direction of the DOE Office of FreedomCAR and Vehicle Technologies Program, Power Electronics and Electric Machinery Program. In this role, ORNL serves on the FreedomCAR Electrical and Electronics Technical Team, evaluates proposals for DOE, and lends its technological expertise to the direction of projects and

  10. FY2007 Oak Ridge National Laboratory Annual Progress Report for the Power Electronics and Electric Machinery Program

    SciTech Connect

    Olszewski, Mitchell

    2007-10-01

    the efficiency and performance targets at the vehicle level have been achieved. The research performed under this subprogram will help remove technical and cost barriers to enable the development of technology for use in such advanced vehicles as hybrid and fuel-cell-powered automobiles that meet the goals of the FreedomCAR and Vehicle Technologies Program. A key element in making hybrid electric vehicles (HEVs) practical is providing an affordable electric traction drive system. This will require attaining weight, volume, and cost targets for the power electronics and electrical machines subsystems of the traction drive system. Areas of development include these: (1) novel traction motor designs that result in increased power density and lower cost; (2) inverter technologies involving new topologies to achieve higher efficiency and the ability to accommodate higher-temperature environments; (3) converter concepts that employ means of reducing the component count and integrating functionality to decrease size, weight, and cost; (4) more effective thermal control and packaging technologies; and (5) integrated motor/inverter concepts. The Oak Ridge National Laboratory's (ORNL's) Power Electronics and Electric Machinery Research Center conducts fundamental research, evaluates hardware, and assists in the technical direction of the DOE Office of FreedomCAR and Vehicle Technologies Program, APEEM subprogram. In this role, ORNL serves on the FreedomCAR Electrical and Electronics Technical Team, evaluates proposals for DOE, and lends its technological expertise to the direction of projects and evaluation of developing technologies. ORNL also executes specific projects for DOE. The following report discusses those projects carried out in FY 2007 and conveys highlights of their accomplishments. Numerous project reviews, technical reports, and papers have been published for these efforts, if the reader is interested in pursuing details of the work.

  11. P1.2 -- Hybrid Electric Vehicle and Lithium Polymer NEV Testing

    SciTech Connect

    J. Francfort

    2006-06-01

    The U.S. Department of Energy’s Advanced Vehicle Testing Activity tests hybrid electric, pure electric, and other advanced technology vehicles. As part of this testing, 28 hybrid electric vehicles (HEV) are being tested in fleet, dynamometer, and closed track environments. This paper discusses some of the HEV test results, with an emphasis on the battery performance of the HEVs. It also discusses the testing results for a small electric vehicle with a lithium polymer traction battery.

  12. The Affording Mars Workshop: Background and Recommendations

    NASA Technical Reports Server (NTRS)

    Thronson, Harley A.; Carberry, Christopher

    2014-01-01

    . The workshop was organized around three topical breakout sessions: 1. The ISS and the path to Mars: The critical coming decade 2. Affordability and sustainability: what does it mean and what are its implications within guidelines established at the start of the workshop? 3. Notional sequence(s) of cost-achievable missions for the 2020s to 2030s, including capability objectives at each stage and opportunities for coordinated robotic partnerships.

  13. Crashworthy Seats Would Afford Superior Protection

    NASA Technical Reports Server (NTRS)

    Gohmert, Dustin

    2009-01-01

    Seats to prevent or limit crash injuries to astronauts aboard the crew vehicle of the Orion spacecraft are undergoing development. The design of these seats incorporates and goes beyond crash-protection concepts embodied in prior spacecraft and racing-car seats to afford superior protection against impacts. Although the seats are designed to support astronauts in a recumbent, quasi-fetal posture that would likely not be suitable for non-spacecraft applications, parts of the design could be adapted to military and some civilian aircraft seats and to racing car seats to increase levels of protection. The main problem in designing any crashworthy seat is to provide full support of the occupant against anticipated crash and emergency-landing loads so as to safely limit motion, along any axis, of any part of the occupant s body relative to (1) any other part of the occupant s body, (2) the spacecraft or other vehicle, and (3) the seat itself. In the original Orion spacecraft application and in other applications that could easily be envisioned, the problem is complicated by severe limits on space available for the seat, a requirement to enable rapid egress by the occupant after a crash, and a requirement to provide for fitting of the seat to a wide range of sizes and shapes of a human body covered by a crash suit, space suit, or other protective garment. The problem is further complicated by other Orion-application-specific requirements that must be omitted here for the sake of brevity. To accommodate the wide range of crewmember body lengths within the limits on available space in the original Orion application, the design provides for taller crewmembers to pull their legs back closer toward their chests, while shorter crewmembers can allow their legs to stretch out further. The range of hip-support seat adjustments needed to effect this accommodation, as derived from NASA s Human Systems Integration Standard, was found to define a parabolic path along which the knees

  14. Visceral pain triggered by traction on the ileocecal ligament with ileitis

    PubMed Central

    Janyaro, Habibullah; Wan, Juan; Tahir, Adnan H; Shah, Manoj K; Li, Xiao-Jing; Ding, Ming-Xing

    2016-01-01

    Background Visceral pain is a common symptom of several gastrointestinal disorders. Despite tremendous progress in understanding its basic mechanisms, it remains a significant health challenge for clinicians. The present study quantified the intensity of visceral pain using ileocecal ligament traction on an inflamed ileum in goats. Materials and methods A total of 36 male goats weighing 20.05±2.1 kg were randomly allocated equally into a 2,4,6-trinitrobenzenesulfonic acid (TNBS) group (n=18) and a saline group (n=18). Ileitis was induced via the injection of 30 mg TNBS dissolved in 30% ethanol into the ileal wall through a laparotomy. An equal volume of normal saline was injected into the ileal wall of the saline goats. Behavioral responses to traction (2, 4, and 6 N) on the ileocecal ligament were observed on days 3, 7, and 14. Six goats from each group received a laparotomy and partial intestinal resection for ileal sample collection immediately after behavioral testing on days 3, 7, and 14. Ileal histopathological changes were assessed and concentrations of myeloperoxidase, IL-1β, IL-6, and TNFα investigated using enzyme-linked immunosorbent assay. Results The TNBS-treated goats exhibited remarkably increased macroscopic scores, mast-cell counts, myeloperoxidase, and TNFα concentrations on days 3 and 7 compared to the saline group, and increased microscopic scores and IL-1β and IL-6 concentrations on days 3–14. The TNBS-treated goats exhibited behavioral changes in response to traction in the same pattern as their microscopic changes and cytokine levels. The traction force correlated positively with pain-behavior responses. Conclusion Traction on the ileocecal ligament of goats with ileitis provoked an apparent, stable, and reproducible ileum-derived pain. The current model may be helpful in evaluating the efficacy of new drugs for the management of visceral pain and in investigating its underlying mechanisms. PMID:27757049

  15. Long-Life, Lightweight, Multi-Roller Traction Drives for Planetary Vehicle Surface Exploration

    NASA Technical Reports Server (NTRS)

    Klein, Richard C.; Fusaro, Robert L.; Dimofte, Florin

    2012-01-01

    NASA s initiative for Lunar and Martian exploration will require long lived, robust drive systems for manned vehicles that must operate in hostile environments. The operation of these mechanical drives will pose a problem because of the existing extreme operating conditions. Some of these extreme conditions include operating at a very high or very cold temperature, operating over a wide range of temperatures, operating in very dusty environments, operating in a very high radiation environment, and operating in possibly corrosive environments. Current drive systems use gears with various configurations of teeth. These gears must be lubricated with oil (or grease) and must have some sort of a lubricant resupply system. For drive systems, oil poses problems such as evaporation, becoming too viscous and eventually freezing at cold temperatures, being too thin to lubricate at high temperatures, being degraded by the radiation environment, being contaminated by the regolith (soil), and if vaporized (and not sealed), it will contaminate the regolith. Thus, it may not be advisable or even possible to use oil because of these limitations. An oil-less, compact traction vehicle drive is a drive designed for use in hostile environments like those that will be encountered on planetary surfaces. Initially, traction roller tests in vacuum were conducted to obtain traction and endurance data needed for designing the drives. From that data, a traction drive was designed that would fit into a prototype lunar rover vehicle, and this design data was used to construct several traction drives. These drives were then tested in air to determine their performance characteristics, and if any final corrections to the designs were necessary. A limitation with current speed reducer systems such as planetary gears and harmonic drives is the high-contact stresses that occur at tooth engagement and in the harmonic drive wave generator interface. These high stresses induce high wear of solid

  16. Superior effect of forceful compared with standard traction mobilizations in hip disability?

    PubMed

    Vaarbakken, Kjartan; Ljunggren, Anne Elisabeth

    2007-09-01

    THE OBJECTIVE OF THIS STUDY WAS TO COMPARE THE EFFECTIVENESS OF TWO COMPILED PHYSIOTHERAPY PROGRAMS: one including forceful traction mobilizations, the other including traction with unknown force, in patients with hip disability according to ICF (the International Classification of Functioning, Disability and Health, 2001; WHO), using a block randomized, controlled trial with two parallel treatment groups in a regular private outpatient physiotherapy practice. In the experimental group (E; n = 10) and control group (C; n = 9), the mean (+/-SD) age for all participants was 59 +/- 12 years. They were recruited from outpatient physiotherapy clinics, had persistent pain located at the hip joint for >8 weeks and hip hypomobility. Both groups received exercise, information and manual traction mobilization. In E, the traction force was progressed to 800 N, whereas in C it was unknown. Major outcome measure was the median total change score >/=20 points or >/=50% of the disease- and joint-specific Hip disability and Osteoarthritis Outcome Score (HOOS), compiled of Pain, Stiffness, Function and Hip-related quality of life (ranging 0-100). The mean (range) treatments received were 13 (7-16) over 5-12 weeks and 20 (18-24) over 12 weeks for E and C, respectively. The experimental group showed superior clinical post-treatment effect on HOOS (>/=20 points), in six of 10 participants compared with none of nine in the control group (p = 0.011). The effect size was 1.1. The results suggest that a compiled physiotherapy program including forceful traction mobilizations are short-term effective in reducing self-rated hip disability in primary healthcare. The long-term effect is to be documented.

  17. Efficacy of the technique of piezoelectric corticotomy for orthodontic traction of impacted mandibular third molars.

    PubMed

    Ma, Zhigui; Xu, Guangzhou; Yang, Chi; Xie, Qianyang; Shen, Yuqing; Zhang, Shanyong

    2015-04-01

    Our aim was to assess the efficacy of piezoelectric corticotomy for orthodontic traction of mandibular third molars close to the inferior alveolar nerve. Thirty patients with impacted third molars close to the nerve were included in the study, 15 of whom were treated with conventional orthodontic traction and 15 with piezoelectric corticotomy. We recorded duration of treatment including exposure and orthodontic traction, and time to the final extraction. Postoperative complications including trismus, swelling, and pain were also noted. Alveolar bone levels mesial and distal to the second molars were evaluated on cone-beam computed tomographic (CT) images. Student's t test was used to assess the significance of differences between the groups. After orthodontic treatments all impacted third molars were successfully removed from the inferior alveolar nerve without neurological damage. The mean (SD) duration of surgical exposure in the piezoelectric corticotomy group was significantly longer than that in the conventional group (p=0.01). The mean (SD) duration of traction was 4 (2.3) months after piezoelectric corticotomy, much shorter than the 7.5 (1.3) months in the conventional group (p=0.03). There were no significant differences in postoperative complications between the groups. There was a significant increase in the distal alveolar height of second molars after treatment in both groups (p<0.01). We conclude that the use of piezoelectric corticotomy allows more efficient and faster traction of third molars with a close relation between the root and the inferior alveolar nerve, although it took longer than the traditional technique.

  18. Superior effect of forceful compared with standard traction mobilizations in hip disability?

    PubMed Central

    Vaarbakken, Kjartan; Ljunggren, Anne Elisabeth

    2007-01-01

    The objective of this study was to compare the effectiveness of two compiled physiotherapy programs: one including forceful traction mobilizations, the other including traction with unknown force, in patients with hip disability according to ICF (the International Classification of Functioning, Disability and Health, 2001; WHO), using a block randomized, controlled trial with two parallel treatment groups in a regular private outpatient physiotherapy practice. In the experimental group (E; n = 10) and control group (C; n = 9), the mean (±SD) age for all participants was 59 ± 12 years. They were recruited from outpatient physiotherapy clinics, had persistent pain located at the hip joint for >8 weeks and hip hypomobility. Both groups received exercise, information and manual traction mobilization. In E, the traction force was progressed to 800 N, whereas in C it was unknown. Major outcome measure was the median total change score ≥20 points or ≥50% of the disease- and joint-specific Hip disability and Osteoarthritis Outcome Score (HOOS), compiled of Pain, Stiffness, Function and Hip-related quality of life (ranging 0–100). The mean (range) treatments received were 13 (7–16) over 5–12 weeks and 20 (18–24) over 12 weeks for E and C, respectively. The experimental group showed superior clinical post-treatment effect on HOOS (≥20 points), in six of 10 participants compared with none of nine in the control group (p = 0.011). The effect size was 1.1. The results suggest that a compiled physiotherapy program including forceful traction mobilizations are short-term effective in reducing self-rated hip disability in primary healthcare. The long-term effect is to be documented. PMID:18833335

  19. Balancing adequacy and affordability?: Essential Health Benefits under the Affordable Care Act.

    PubMed

    Haeder, Simon F

    2014-12-01

    The Essential Health Benefits provisions under the Affordable Care Act require that eligible plans provide coverage for certain broadly defined service categories, limit consumer cost-sharing, and meet certain actuarial value requirements. Although the Department of Health and Human Services (HHS) was tasked with the regulatory development of these EHB under the ACA, the department quickly devolved this task to the states. Not surprisingly, states fully exploited the leeway provided by HHS, and state decision processes and outcomes differed widely. However, none of the states took advantage of the opportunity to restructure fundamentally their health insurance markets, and only a very limited number of states actually included sophisticated policy expertise in their decisionmaking processes. As a result, and despite a major expansion of coverage, the status quo ex ante in state insurance markets was largely perpetuated. Decisionmaking for the 2016 revisions should be transparent, included a wide variety of stakeholders and policy experts, and focus on balancing adequacy and affordability. However, the 2016 revisions provide an opportunity to address these previous shortcomings.

  20. Training and certification of doctors of chiropractic in delivering manual cervical traction forces: Results of a longitudinal observational study.

    PubMed

    Gudavalli, Maruti Ram; Vining, Robert D; Salsbury, Stacie A; Goertz, Christine M

    2014-10-01

    Objective : Doctors of chiropractic (DCs) use manual cervical distraction to treat patients with neck pain. Previous research demonstrates variability in traction forces generated by different DCs. This article reports on a training protocol and monthly certification process using bioengineering technology to standardize cervical traction force delivery among clinicians. Methods : This longitudinal observational study evaluated a training and certification process for DCs who provided force-based manual cervical distraction during a randomized clinical trial. The DCs completed a 7-week initial training that included instructional lectures, observation, and guided practice by a clinical expert, followed by 3 hours of weekly practice sessions delivering the technique to asymptomatic volunteers who served as simulated patients. An instrument-modified table and computer software provided the DCs with real-time audible and visual feedback on the traction forces they generated and graphical displays of the magnitude of traction forces as a function of time immediately after the delivery of the treatment. The DCs completed monthly certifications on traction force delivery throughout the trial. Descriptive accounts of certification attempts are provided. Results : Two DCs achieved certification in traction force delivery over 10 consecutive months. No certification required more than 3 attempts at C5 and occiput contacts for 3 force ranges (0-20 N, 21-50 N, and 51-100 N). Conclusions : This study demonstrates the feasibility of a training protocol and certification process using bioengineering technology for training DCs to deliver manual cervical distraction within specified traction force ranges over a 10-month period.

  1. Are Americans finding affordable coverage in the health insurance marketplaces? Results from the Commonwealth Fund Affordable Care Act Tracking Survey.

    PubMed

    Rasmussen, Petra W; Collins, Sara R; Doty, Michelle M; Beutel, Sophie

    2014-09-01

    By the end of the first open enrollment period for coverage offered through the Affordable Care Act's marketplaces, increasing numbers of people said they found it easy to find a plan they could afford, according to The Commonwealth Fund's Affordable Care Act Tracking Survey, April-June 2014. Adults with low or moderate incomes were more likely to say it was easy to find an affordable plan than were adults with higher incomes. Adults with low or moderate incomes who purchased a plan through the marketplaces this year have similar premium costs and deductibles as adults in the same income ranges with employer-provided coverage. A majority of adults with marketplace coverage gave high ratings to their insurance and were confident in their ability to afford the care they need when sick. PMID:25265646

  2. Modification of the SHABERTH bearing code to incorporate RP-1 and a discussion of the traction model

    NASA Technical Reports Server (NTRS)

    Woods, Claudia M.

    1990-01-01

    Recently developed traction data for Rocket Propellant 1 (RP-1), a hydrocarbon fuel of the kerosene family, was used to develop the parameters needed by the bearing code SHABERTH in order to include RP-1 as a lubricant choice. The procedure for inputting data for a new lubricant choice is reviewed, and the theoretical fluid traction model is discussed. Comparisons are made between experimental traction data and those predicted by SHABERTH for RP-1. All data needed to modify SHABERTH for use with RP-1 as a lubricant are specified.

  3. The Value of Full Correction: Achieving Excellent and Affordable Results.

    PubMed

    Kaplan, Julie Bass

    2016-01-01

    Patients often come to medical aesthetic offices with hopes to fully correct lost facial volume and achieve a natural appearance. Unfortunately, the cost per syringe of dermal filler can be a barrier to desired outcomes. Many aesthetic practitioners do the best they can with the amount of product the patient can afford, often falling short of the "wow" effect for the patient. This article describes what one office implemented to solve the conundrum of affordability while still allowing offices to cover its own financial realities. This tool can help patients achieve beautiful, natural, and affordable outcomes while helping offices advance in manufacturer's tiers, improve word-of-mouth advertising, and increase job satisfaction.

  4. Safe, Affordable, Nuclear Thermal Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Houts, M. G.; Kim, T.; Emrich, W. J.; Hickman, R. R.; Broadway, J. W.; Gerrish, H. P.; Doughty, G. E.

    2014-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progress made under the NCPS project could help enable both advanced NTP and advanced Nuclear Electric Propulsion (NEP).

  5. Can consumers make affordable care affordable? The value of choice architecture.

    PubMed

    Johnson, Eric J; Hassin, Ran; Baker, Tom; Bajger, Allison T; Treuer, Galen

    2013-01-01

    Tens of millions of people are currently choosing health coverage on a state or federal health insurance exchange as part of the Patient Protection and Affordable Care Act. We examine how well people make these choices, how well they think they do, and what can be done to improve these choices. We conducted 6 experiments asking people to choose the most cost-effective policy using websites modeled on current exchanges. Our results suggest there is significant room for improvement. Without interventions, respondents perform at near chance levels and show a significant bias, overweighting out-of-pocket expenses and deductibles. Financial incentives do not improve performance, and decision-makers do not realize that they are performing poorly. However, performance can be improved quite markedly by providing calculation aids, and by choosing a "smart" default. Implementing these psychologically based principles could save purchasers of policies and taxpayers approximately 10 billion dollars every year. PMID:24367484

  6. Can Consumers Make Affordable Care Affordable? The Value of Choice Architecture

    PubMed Central

    Johnson, Eric J.; Hassin, Ran; Baker, Tom; Bajger, Allison T.; Treuer, Galen

    2013-01-01

    Tens of millions of people are currently choosing health coverage on a state or federal health insurance exchange as part of the Patient Protection and Affordable Care Act. We examine how well people make these choices, how well they think they do, and what can be done to improve these choices. We conducted 6 experiments asking people to choose the most cost-effective policy using websites modeled on current exchanges. Our results suggest there is significant room for improvement. Without interventions, respondents perform at near chance levels and show a significant bias, overweighting out-of-pocket expenses and deductibles. Financial incentives do not improve performance, and decision-makers do not realize that they are performing poorly. However, performance can be improved quite markedly by providing calculation aids, and by choosing a “smart” default. Implementing these psychologically based principles could save purchasers of policies and taxpayers approximately 10 billion dollars every year. PMID:24367484

  7. Object Affordances Potentiate Responses but Do Not Guide Attentional Prioritization

    PubMed Central

    Yamani, Yusuke; Ariga, Atsunori; Yamada, Yuki

    2016-01-01

    Handled objects automatically activate afforded responses. The current experiment examined whether objects that afford a response are also prioritized for attentional processing in visual search. Targets were pictures of coffee cups with handles oriented either to the right or the left. Subjects searched for a target, a right-handled vs. left-handled coffee cup, among a varying number of distractor cups oriented in the opposite direction. Responses were faster when the direction of target handle and the key press were spatially matched than mismatched (stimulus-response compatibility (SRC) effect), but object affordance did not moderate slopes of the search functions, indicating the absence of attentional prioritization effect. These findings imply that handled objects prime afforded responses without influencing attentional prioritization. PMID:26793077

  8. Development of Basic Housing Systems for Maximum Affordability

    SciTech Connect

    Aglan, H.; Gibbons, A.; McQueen, T.M.; Morris, C.; Raines, J.; Wendt, R.L.

    1999-04-19

    The ability to provide safe, habitable, comfortable housing for very low income residents within the target budget of $10,000 presents unique design and construction challenges. However, a number of preliminary conclusions have been inferred as being important concepts relative to the study of affordable housing. The term affordable housing can have many meanings and research is needed to define this explicitly. As it is most often used, affordable housing refers to an economic relationship between the price of housing, household income and current interest rates available from a lending institution. There is no direct relationship between architectural style, construction technology or user needs and the concept of affordability. For any home to be affordable, the home owner must balance the combination of housing needs and desires within the limits of an actual budget. There are many misconceptions that affordable housing must be defined as housing for those who cannot afford the free-market price. The concept of affordable housing must also include a component that recognizes the quality of the housing as an important element of the design and construction. In addition, responses to local climate impacts are necessary and are always part of a regional expression of architectural design. By using careful planning and design it may be possible to construct a limited dwelling unit today for a sum of approximately $10,000. Since the organization of the construction process must involve the owner/occupants as well as other volunteers, the project must not only be well conceived, but well developed and coordinated.

  9. Why the affordable care act needs a better name: 'Americare'.

    PubMed

    Sage, William M

    2010-08-01

    The culmination of a century's effort to enact universal coverage in the United States is a law with an uninspiring title, the Patient Protection and Affordable Care Act, and an even more awkward acronym, PPACA. The Obama administration has decided to call the legislation the Affordable Care Act, but the expansion of health coverage that the law sets in motion has no name, and therefore no identity. It badly needs one.

  10. Safe Affordable Fission Engine-(SAFE-) 100a Heat Exchanger Thermal and Structural Analysis

    NASA Technical Reports Server (NTRS)

    Steeve, B. E.

    2005-01-01

    A potential fission power system for in-space missions is a heat pipe-cooled reactor coupled to a Brayton cycle. In this system, a heat exchanger (HX) transfers the heat of the reactor core to the Brayton gas. The Safe Affordable Fission Engine- (SAFE-) 100a is a test program designed to thermally and hydraulically simulate a 95 Btu/s prototypic heat pipe-cooled reactor using electrical resistance heaters on the ground. This Technical Memorandum documents the thermal and structural assessment of the HX used in the SAFE-100a program.

  11. Biosignal PI, an Affordable Open-Source ECG and Respiration Measurement System

    PubMed Central

    Abtahi, Farhad; Snäll, Jonatan; Aslamy, Benjamin; Abtahi, Shirin; Seoane, Fernando; Lindecrantz, Kaj

    2015-01-01

    Bioimedical pilot projects e.g., telemedicine, homecare, animal and human trials usually involve several physiological measurements. Technical development of these projects is time consuming and in particular costly. A versatile but affordable biosignal measurement platform can help to reduce time and risk while keeping the focus on the important goal and making an efficient use of resources. In this work, an affordable and open source platform for development of physiological signals is proposed. As a first step an 8–12 leads electrocardiogram (ECG) and respiration monitoring system is developed. Chips based on iCoupler technology have been used to achieve electrical isolation as required by IEC 60601 for patient safety. The result shows the potential of this platform as a base for prototyping compact, affordable, and medically safe measurement systems. Further work involves both hardware and software development to develop modules. These modules may require development of front-ends for other biosignals or just collect data wirelessly from different devices e.g., blood pressure, weight, bioimpedance spectrum, blood glucose, e.g., through Bluetooth. All design and development documents, files and source codes will be available for non-commercial use through project website, BiosignalPI.org. PMID:25545268

  12. Stable and variable affordances are both automatic and flexible

    PubMed Central

    Borghi, Anna M.; Riggio, Lucia

    2015-01-01

    The mere observation of pictures or words referring to manipulable objects is sufficient to evoke their affordances since objects and their nouns elicit components of appropriate motor programs associated with object interaction. While nobody doubts that objects actually evoke motor information, the degree of automaticity of this activation has been recently disputed. Recent evidence has indeed revealed that affordances activation is flexibly modulated by the task and by the physical and social context. It is therefore crucial to understand whether these results challenge previous evidence showing that motor information is activated independently from the task. The context and the task can indeed act as an early or late filter. We will review recent data consistent with the notion that objects automatically elicit multiple affordances and that top-down processes select among them probably inhibiting motor information that is not consistent with behavior goals. We will therefore argue that automaticity and flexibility of affordances are not in conflict. We will also discuss how language can incorporate affordances showing similarities, but also differences, between the motor information elicited by vision and language. Finally we will show how the distinction between stable and variable affordances can accommodate all these effects. PMID:26150778

  13. Affordability of alcohol and alcohol-related mortality in Belarus.

    PubMed

    Razvodovsky, Yury E

    2013-01-01

    Alcohol abuse has numerous adverse health and social consequences. The consumer response to changes in alcohol affordability is an important issue on alcohol policy debates. Studies from many countries have shown an inverse relationship between alcohol prices and alcohol consumption in the population. There are, however, suggestions that increasing the price of alcohol by rising taxes may have limited effect on alcohol-related problems, associated with long-term heavy drinking. The aim of the present study was to evaluate the relationship between alcohol affordability and alcohol-related mortality rates in post-Soviet Belarus. For this purpose trends in alcohol-related mortality rates (mortality from liver cirrhosis, pancreatitis, alcoholism and alcohol psychoses) and affordability of vodka between 1990 and 2010 were compared. The time series analysis revealed that 1% increase in vodka affordability is associated with an increase in liver cirrhosis mortality of 0,77%, an increase in pancreatitis mortality of 0.53%, an increase in mortality from alcoholism and alcohol psychoses of 0,70%. The major conclusion emerging from this study is that affordability of alcohol is one of the most important predictor of alcohol-related problems in a population. These findings provide additional evidence that decreasing in affordability of alcohol is an effective strategy for reducing alcohol consumption and alcohol-related harm.

  14. Affordable Exploration of Mars: Recommendations from a Community Workshop

    NASA Technical Reports Server (NTRS)

    Thronson, Harley A.; Carberry, Chris; Cassady, R. Joseph; Cooke, Doug; Kirkpatrick, Jim; Perino, Maria Antonietta; Raftery, Michael; Westenberg, Artemis; Zucker, Richard

    2014-01-01

    There is a growing opinion that within two decades initial human missions to Mars are affordable under plausible budget scenarios, with sustained international participation, and --- especially --- without requiring those first missions to achieve a burdensome number of goals. In response to this view, a group of experts from the Mars exploration stakeholder communities attended the "Affording Mars" workshop at George Washington University in December 2013. Participants reviewed scenarios for proposed affordable and sustainable human and robotic exploration of Mars, the role of the International Space Station as the essential early step toward humans to Mars, possible "bridge" or "transition" missions in the 2020s, key capabilities required for affordable initial missions, international partnerships, and usable definitions of affordability and sustainability. We report here the findings, observations, and recommendations that were agreed to at that workshop. In the context of affordable early missions to Mars, we also discuss the recent report of the National Research Council on human space flight and a pair of recent scenarios that appear to promise reduced costs.

  15. Applications of traction force microscopy in measuring adhesion molecule dependent cell contractility

    NASA Astrophysics Data System (ADS)

    Mann, Cynthia Marie

    This work describes the use of polyacrylamide hydrogels as controlled elastic modulus substrates for single cell traction force microscopy studies. The first section describes the use of EDC/NHS chemistry to convalently link microbeads to the hydrogel matrix for the purpose of performing long-term traction force studies (7 days). The final study uses the C2C12 cell line to demonstrate that integrin-mediated adhesion to soft substrates causes different cell behavior than N-cahderin-mediated adhesion to soft substrates. Cells plated on laminin-coated hydrogels exhibited stiffness dependent increases in cell spreading, whereas cells plated on N-cadherin-coated substrates. Similarly, cells plated on laminin-coated substrates exhibited substrate stiffness dependent increases in normalized net contractile moment, however the same cells plated on N-cadherin-coated substrates were unable to deform any but the softest hydrogels.

  16. Effect of positive pulse charge waveforms on the energy efficiency of lead-acid traction cells

    NASA Technical Reports Server (NTRS)

    Smithrick, J. J.

    1981-01-01

    The effects of four different charge methods on the energy conversion efficiency of 300 ampere hour lead acid traction cells were investigated. Three of the methods were positive pulse charge waveforms; the fourth, a constant current method, was used as a baseline of comparison. The positive pulse charge waveforms were: 120 Hz full wave rectified sinusoidal; 120 Hz silicon controlled rectified; and 1 kHz square wave. The constant current charger was set at the time average pulse current of each pulse waveform, which was 150 amps. The energy efficiency does not include charger losses. The lead acid traction cells were charged to 70 percent of rated ampere hour capacity in each case. The results of charging the cells using the three different pulse charge waveforms indicate there was no significant difference in energy conversion efficiency when compared to constant current charging at the time average pulse current value.

  17. Nail hooks and elastic bands external dynamic traction for fractures of the proximal interphalangeal joint.

    PubMed

    Siddiqui, Farhaj; Hossain, Shahan; Huq, Nasimul

    2012-09-01

    Intra-articular fractures of the proximal interphalangeal joint remain a treatment challenge for hand specialists. The purpose of this investigation was to review the results of 12 patients, 6 men and 6 women (average age, 21 y), who were treated using the nail hooks and elastic bands external dynamic traction technique for their intra-articular proximal interphalangeal joint fractures. Of the total 12 fractures, 6 involved the proximal phalanx and 6 involved the middle phalanx. The final arc of motion at the proximal interphalangeal joint averaged 89 degrees (range, 25 to 111 degrees). At the conclusion of treatment: 1 patient developed a radial deviation and 1 developed a slight ulnar deviation. All patients were able to return to their preinjury level of functioning. Nail hooks and elastic bands external dynamic traction provides an effective treatment for intra-articular proximal interphalangeal joint fractures. It is an inexpensive, easily applied, nonoperative method of treatment. PMID:22913996

  18. Fatigue life analysis for traction drives with application to a toroidal type geometry

    NASA Technical Reports Server (NTRS)

    Coy, J. J.; Loewenthal, S. H.; Zaretsky, E. V.

    1976-01-01

    A contact fatigue life analysis for traction drives was developed which was based on a modified Lundberg-Palmgren theory. The analysis was used to predict life for a cone-roller toroidal traction drive. A 90-percent probability of survival was assumed for the calculated life. Parametric results were presented for life and Hertz contact stress as a function of load, drive ratio, and size. A design study was also performed. The results were compared to previously published work for the dual cavity toroidal drive as applied to a typical compact passenger vehicle drive train. For a representative duty cycle condition wherein the engine delivers 29 horsepower at 2000 rpm with the vehicle moving at 48.3 km/hr (30 mph) the drive life was calculated to be 19,200 km (11 900 miles).

  19. Model-based traction force microscopy reveals differential tension in cellular actin bundles.

    PubMed

    Soiné, Jérôme R D; Brand, Christoph A; Stricker, Jonathan; Oakes, Patrick W; Gardel, Margaret L; Schwarz, Ulrich S

    2015-03-01

    Adherent cells use forces at the cell-substrate interface to sense and respond to the physical properties of their environment. These cell forces can be measured with traction force microscopy which inverts the equations of elasticity theory to calculate them from the deformations of soft polymer substrates. We introduce a new type of traction force microscopy that in contrast to traditional methods uses additional image data for cytoskeleton and adhesion structures and a biophysical model to improve the robustness of the inverse procedure and abolishes the need for regularization. We use this method to demonstrate that ventral stress fibers of U2OS-cells are typically under higher mechanical tension than dorsal stress fibers or transverse arcs.

  20. Wide resection of traction induced radial nerve injury with cable grafting leads to full recovery.

    PubMed

    Henry, Mark

    2006-12-01

    The specific clinical setting of high-energy open humerus fractures combined with radial nerve transection has typically led to poor final outcomes with respect to recovery of nerve function. Attention has focused on the issue of an expanded zone of nerve injury induced by longitudinal traction. The fundamental principle of nerve grafting is to bypass the zone of injury. If direct repair or short nerve grafts are placed within the zone of injury, limited recovery should be expected, and this is exactly what has been documented. Wide resection of the zone of traction induced injury, particularly from the distal injured nerve trunk and replacement with long cable grafts has the potential for improved outcomes. Complete nerve recovery to 5/5 manual motor power testing and bilaterally equivalent grip strength is reported in two initial cases treated according to the wide resection plan.

  1. An optical Moiré technique for cell traction force mapping

    NASA Astrophysics Data System (ADS)

    Zheng, Xiaoyu; Zhang, Xin

    2008-12-01

    Cells alter their shape and morphology and interact with their surrounding environment. Mechanical forces developed by cells to their surrounding environments are fundamental to many physiological processes, such as cell growth, division, migration and apoptosis. In this paper, a novel optical Moiré based biomechanol force sensor was developed for cell traction force mapping. We utilized coherent laser beams to illuminate periodic polymeric substrates where isolated cells were cultured. We demonstrated one-dimensional and two-dimensional traction force mapping via optical Moiré for both cardiac myocytes and vascular smooth muscle cells. The magnification effect of the Moiré fringe pattern permits a real time monitoring of the mechanical interaction between isolated cells and their underlying periodic polymeric structures.

  2. Concept for a Differential Lock and Traction Control Model in Automobiles

    NASA Astrophysics Data System (ADS)

    Shukul, A. K.; Hansra, S. K.

    2014-01-01

    The automobile is a complex integration of electronics and mechanical components. One of the major components is the differential which is limited due to its shortcomings. The paper proposes a concept of a cost effective differential lock and traction for passenger cars to sports utility vehicles alike, employing a parallel braking mechanism coming into action based on the relative speeds of the wheels driven by the differential. The paper highlights the employment of minimum number of components unlike the already existing systems. The system was designed numerically for the traction control and differential lock for the world's cheapest car. The paper manages to come up with all the system parameters and component costing making it a cost effective system.

  3. Cell Shapes and Traction Forces Determine Stress in Motile Confluent Tissue

    NASA Astrophysics Data System (ADS)

    Yang, Xingbo; Bi, Dapeng; Czajkowski, Michael; Manning, Lisa; Marchetti, Cristina

    Collective cell migration is a highly regulated process involved in wound healing, cancer metastasis and morphogenesis. The understanding of the regulatory mechanism requires the study of mechanical interactions among cells that coordinate their active motion. To this end, we develop a method that determines cellular forces and tissue stresses from experimentally accessible cell shapes and traction forces. This approach allows us for the first time to calculate membrane tensions and hydrostatic pressures at a cellular level in collective migrating cell layers out of equilibrium. It helps us understand the mechanical origin of tissue stresses as previous inferred using Traction Force Microscopy (TFM). We test this approach on a new model of motile confluent tissue, which we term Self-propelled Voronoi Model (SPV) that incorporates cell elasticity, Contractility and motility. With the model, we explore the mechanical properties of confluent motile tissue as a function of cell activities and cell shapes in various geometries.

  4. Model-based Traction Force Microscopy Reveals Differential Tension in Cellular Actin Bundles

    PubMed Central

    Soiné, Jérôme R. D.; Brand, Christoph A.; Stricker, Jonathan; Oakes, Patrick W.; Gardel, Margaret L.; Schwarz, Ulrich S.

    2015-01-01

    Adherent cells use forces at the cell-substrate interface to sense and respond to the physical properties of their environment. These cell forces can be measured with traction force microscopy which inverts the equations of elasticity theory to calculate them from the deformations of soft polymer substrates. We introduce a new type of traction force microscopy that in contrast to traditional methods uses additional image data for cytoskeleton and adhesion structures and a biophysical model to improve the robustness of the inverse procedure and abolishes the need for regularization. We use this method to demonstrate that ventral stress fibers of U2OS-cells are typically under higher mechanical tension than dorsal stress fibers or transverse arcs. PMID:25748431

  5. Fast charging nickel-metal hydride traction batteries

    NASA Astrophysics Data System (ADS)

    Yang, Xiao Guang; Liaw, Bor Yann

    This paper describes the fast charge ability, or "fast rechargeability", of nominal 85 Ah Ni-MH modules under various fast charge conditions, including constant current (CC); typically 1-3C, and constant power (CP) regimes. Our tests revealed that there is no apparent difference between CC and CP fast charge regimes with respect to charge efficiency and time. Following the USABC Electric Vehicle Battery Test Procedures Manual (Revision 2, 1996), we demonstrated that we were able to return 40% state of charge (SOC) from 60% depth of discharge (DOD) to 20% DOD within 15 min. Most importantly, we found that the internal pressure of the cell is the most critical parameter in the control of the fast charge process and the safe operation of the modules.

  6. Creep force modelling for rail traction vehicles based on the Fastsim algorithm

    NASA Astrophysics Data System (ADS)

    Spiryagin, Maksym; Polach, Oldrich; Cole, Colin

    2013-11-01

    The evaluation of creep forces is a complex task and their calculation is a time-consuming process for multibody simulation (MBS). A methodology of creep forces modelling at large traction creepages has been proposed by Polach [Creep forces in simulations of traction vehicles running on adhesion limit. Wear. 2005;258:992-1000; Influence of locomotive tractive effort on the forces between wheel and rail. Veh Syst Dyn. 2001(Suppl);35:7-22] adapting his previously published algorithm [Polach O. A fast wheel-rail forces calculation computer code. Veh Syst Dyn. 1999(Suppl);33:728-739]. The most common method for creep force modelling used by software packages for MBS of running dynamics is the Fastsim algorithm by Kalker [A fast algorithm for the simplified theory of rolling contact. Veh Syst Dyn. 1982;11:1-13]. However, the Fastsim code has some limitations which do not allow modelling the creep force - creep characteristic in agreement with measurements for locomotives and other high-power traction vehicles, mainly for large traction creep at low-adhesion conditions. This paper describes a newly developed methodology based on a variable contact flexibility increasing with the ratio of the slip area to the area of adhesion. This variable contact flexibility is introduced in a modification of Kalker's code Fastsim by replacing the constant Kalker's reduction factor, widely used in MBS, by a variable reduction factor together with a slip-velocity-dependent friction coefficient decreasing with increasing global creepage. The proposed methodology is presented in this work and compared with measurements for different locomotives. The modification allows use of the well recognised Fastsim code for simulation of creep forces at large creepages in agreement with measurements without modifying the proven modelling methodology at small creepages.

  7. Numerical investigation of engine-to-slip dynamics for motorcycle traction control applications

    NASA Astrophysics Data System (ADS)

    Massaro, M.; Sartori, R.; Lot, R.

    2011-03-01

    This work discusses the motorcycle engine-to-slip dynamics which are strictly related to the traction control design. A street motorcycle is analysed by means of an advanced mathematical model which also includes the tyre flexibility and the transmission compliance. The effects of the following parameters on engine-to-slip dynamics are investigated: vehicle speed, engaged gear ratio, sprocket absorber flexibility and road properties. Guidelines for increasing the maximum achievable closed-loop bandwidth are given.

  8. A study of various synthetic routes to produce a halogen-labeled traction fluid

    NASA Technical Reports Server (NTRS)

    Jones, W. R., Jr.; Zimmer, H.

    1978-01-01

    Several synthetic routes were studied for the synthesis of the compound 1, 1, 3-trimethyl-1, 3-dicyclohexyl-2 chloropropane. This halogen-labeled fluid would be of use in the study of high traction lubricants under elastohydrodynamic lubrication conditions using infrared emission spectroscopy. The synthetic routes included: dimerization of alpha-methylstyrene, methanol addition to alpha-methylstyrene, a Wittig reaction, and an organometallic approach. Because of steric hindrance and competing reactions, none of these routes were successful.

  9. 77 FR 56911 - Progressive Rail Incorporated-Continuance in Control Exemption-Iowa Traction Railway Company

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-14

    ... operate a 10.4-mile rail line extending from milepost 0.0 at Mason City to milepost 10.4 at Clear Lake in... Traction R.R., Docket No. FD 35670. The transaction may be consummated on or after September 30, 2012 (the.... Therefore, the transaction is exempt from the prior approval requirements of 49 U.S.C. 11323. See 49...

  10. Vehicle non-exhaust emissions from the tyre-road interface - effect of stud properties, traction sanding and resuspension

    NASA Astrophysics Data System (ADS)

    Kupiainen, Kaarle J.; Pirjola, Liisa

    2011-08-01

    In Northern cities respirable street dust emission levels (PM 10) are especially high during spring. The spring time dust has been observed to cause health effects as well as discomfort among citizens. Major sources of the dust are the abrasion products from the pavement and traction sand aggregates that are formed due to the motion of the tyre. We studied the formation of respirable abrasion particles in the tyre-road interface due to tyre studs and traction sanding by a mobile laboratory vehicle Sniffer. The measurements were preformed on a test track, where the influence of varying stud weight and stud number per tyre on PM 10 emissions was studied. Studded tyres resulted in higher emission levels than studless tyres especially with speeds 50 km h -1 and higher; however, by using light weight studs, which approximately halves the weight of studs, or by reducing the number of studs per tyre to half, the emission levels decreased by approximately half. Additionally measurements were done with and without traction sand coverage on the pavement of a public road. After traction sanding the emission levels were not affected by tyre type but by formation and suspension of traction sand related dust from the road surface. The emissions after traction sanding decreased as a function of time as passing vehicles' motion shifted the sand grains away from the areas with most tyre-road contact.

  11. 76 FR 4377 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Affordable...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-25

    ...; Affordable Care Act Enrollment Opportunity Notice Relating to Extension of Dependent Coverage ACTION: Notice... Administration (EBSA) sponsored information collection request (ICR) titled, ``Affordable Care Act Enrollment... Collection: Affordable Care Act Enrollment Opportunity Notice Relating to Extension of Dependent......

  12. Experimental and numerical determination of cellular traction force on polymeric hydrogels

    PubMed Central

    Ng, Soon Seng; Li, Chuan; Chan, Vincent

    2011-01-01

    Anchorage-dependent cells such as smooth muscle cells (SMCs) rely on the transmission of actomyosin-generated traction forces to adhere and migrate on the extracellular matrix. The cellular traction forces exerted by SMCs on substrate can be measured from the deformation of substrate with embedded fluorescent markers. With the synchronous use of phase-contrast and fluorescent microscopy, the deformation of polyacrylamide (PAM) gel substrate can be quantitatively determined using particle image velocimetry. This displacement map is then input as boundary conditions for the stress analysis on PAM gel by the finite-element method. In addition to optical microscopy, atomic force microscopy was also used to characterize the PAM substrate using the contact mode, from which the elasticity of PAM can be quantified using Hertzian theory. This provides baseline information for the stress analysis of PAM gel deformation. The material model introduced for the computational part is the Mooney–Rivlin constitutive law because of its long proven usefulness in predicting polymers' mechanical behaviour. Numerical results showed that adhesive stresses are high around the cell edges, which is in accordance with the general phenomena of cellular focal adhesion. Further calculations on the total traction forces indicate a slightly contact-dominated regime for a broad range of Mooney–Rivlin stiffnesses. PMID:23050082

  13. Characterization of Intracellular Streaming and Traction Forces in Migrating Physarum Plasmodia

    NASA Astrophysics Data System (ADS)

    Zhang, Shun; Meili, Ruedi; Guy, Robert; Lasheras, Juan; Del Alamo, Juan C.

    2014-11-01

    Physarum plasmodium is a model organism for cell migration that exhibits fast intracellular streaming. Single amoebae were seeded and allowed to move on polyacrilamide gels that contained 0.5-micron fluorescent beads. Joint time-lapse sequences of intracellular streaming and gel deformation were acquired respectively in the bright and fluorescent fields under microscope. These images were analyzed using particle image velocimetry (PIV) algorithms, and the traction stresses applied by the amoebae on the surface were computed by solving the elastostatic equation for the gel using the measured bead displacements as boundary conditions. These measurements provide, for the first time, a joint characterization of intracellular mass transport and the forces applied on the substrate of motile amoeboid cells with high resolution in both time and space, enables a through study about the locomotive mechanism and the relation between intracellular flow and traction stress, shedding light on related biomimetic research. The results reveal a pronounced auto-oscillation character in intracellular flow, contact area, centroid speed and strain energy, all with the same periodicity about 100 seconds. Locomotion modes that were distinct in flow/ traction stress pattern as well as migration speed have been discovered and studied.

  14. Height increase, neuromuscular function, and back pain during 6 degrees head-down tilt with traction

    NASA Technical Reports Server (NTRS)

    Styf, J. R.; Ballard, R. E.; Fechner, K.; Watenpaugh, D. E.; Kahan, N. J.; Hargens, A. R.

    1997-01-01

    BACKGROUND: Spinal lengthening and back pain are commonly experienced by astronauts exposed to microgravity. METHODS: To develop a ground-based simulation for spinal adaptation to microgravity, we investigated height increase, neuromuscular function and back pain in 6 subjects all of whom underwent two forms of bed rest for 3 d. One form consisted of 6 degrees of head-down tilt (HDT) with balanced traction, while the other was horizontal bed rest (HBR). Subjects had a 2-week recovery period in between the studies. RESULTS: Total body and spinal length increased significantly more and the subjects had significantly more back pain during HDT with balanced traction compared to HBR. The distance between the lower endplate of L4 and upper endplate of S1, as measured by ultrasonography, increased significantly in both treatments to the same degree. Intramuscular pressures in the erector spinae muscles and ankle torque measurements during plantarflexion and dorsiflexion did not change significantly during either treatment. CONCLUSION: Compared to HBR, HDT with balanced traction may be a better method to simulate changes of total body and spinal lengths, as well as back pain seen in microgravity.

  15. A new model of tethered cord syndrome produced by slow traction.

    PubMed

    Huang, Sheng-Li; Peng, Jun; Yuan, Guo-Lian; Ding, Xiao-Yan; He, Xi-Jing; Lan, Bin-Shang

    2015-01-01

    The development of a suitable animal model is important for clarifying the pathogenesis of tethered cord syndrome (TCS). This study was undertaken to develop a new animal model for investigating the pathogenesis and therapeutic strategies for TCS. A traction device, a filum terminale tractor, was designed exclusively for this experiment. A TCS model was produced in cats using the tractor to fixate the filum terminale to the dorsal aspect of the second sacrum. The responses to tethering were evaluated by electron microscopy and electromyography for detection of somatosensory evoked potentials (SEPs) and motor evoked potentials (MEPs) at designated time points. Progressive swaying gait and lameness in clinical performance were observed with cord traction. Histopathological examination revealed an association between the increasing traction in the spinal cord and the increase in impaired nerve cells. No changes of SEPs and MEPs were detected in the untethered cats, while the latencies of SEPs and MEPs significantly increased in the tethered cats. The TCS model established in this study is simple and reproducible, in which varying degrees of tension could be applied to the neural elements. PMID:25766487

  16. Case studies on local orthodontic traction by minis-implants before implant rehabilitation

    PubMed Central

    Shen, Pei; Xu, Wei-Feng; Ma, Zhi-Gui; Zhang, Shan-Yong; Zhang, Ying

    2015-01-01

    Objective: Dentition defect with malocclusion is a common occurrence in the clinical work. To restore proper occlusion, preprosthetic corrections of these malposed teeth are often indispensible. The use of orthodontic mini-implants as temporary anchorage devices provides a plausible treatment for those patients with local problems. The aim of this study was to present two cases using local orthodontic traction in conjunction with mini-implants to provide necessary conditions for implant rehabilitation in three dimensional space. Clinical consideration: Two cases who had dentition defect with malocclusion were included in the present study. As both of them rejected crown reduction or orthodontics treatment, local orthodontic traction by mini-implants was used to restore normal space for implant rehabilitation in three dimensions. Careful mechanics analysis and personalized mechanical device were under consideration. The results showed that the biological responses of the corrected teeth and the surrounding bony structures appeared normal and acceptable. Moreover the patients achieved an ideal local occlusion with a short treatment time. Conclusion: In conclusion local orthodontic traction by mini-implants was a less-invasive and short-term method with favorable effects and less necessary occlusal adjustments. PMID:26221389

  17. Manual cervical traction reduces alpha-motoneuron excitability in normal subjects.

    PubMed

    Bradnam, L; Rochester, L; Vujnovich, A

    2000-01-01

    The excitability of the Flexor Carpi Radialis alpha-motoneuron pool following manual cervical traction was assessed in twenty asymptomatic subjects, and compared to a hands only intervention. The excitability of the alpha-motoneuron pool was measured indirectly using the Hoffmann (H) reflex. H-reflex recruitment curves were taken to assess the number of alpha-motoneurons (alpha-motoneurons) firing in response to a given incremental increase in stimulation intensity. The rate of rise of the slope of the H-reflex recruitment curve (Hslp) was assessed using linear regression. Following manual cervical traction Hslp was significantly lower than pre-intervention trials. Manual cervical traction, therefore, reduced the excitability of the Flexor Carpi Radialis alpha-motoneuron pool. This effect was mediated by the central nervous system. There was no significant decrease in alpha-motoneuron excitability following the hands only intervention. Hslp was shown to be a more sensitive measure of changes in the H-reflex than the more traditional parameter of Hmax/Mmax ratio and should be used in future studies of this nature.

  18. Thrombin-induced contraction in alveolar epithelial cells probed by traction microscopy.

    PubMed

    Gavara, Núria; Sunyer, Raimon; Roca-Cusachs, Pere; Farré, Ramon; Rotger, Mar; Navajas, Daniel

    2006-08-01

    Contractile tension of alveolar epithelial cells plays a major role in the force balance that regulates the structural integrity of the alveolar barrier. The aim of this work was to study thrombin-induced contractile forces of alveolar epithelial cells. A549 alveolar epithelial cells were challenged with thrombin, and time course of contractile forces was measured by traction microscopy. The cells exhibited basal contraction with total force magnitude 55.0 +/- 12.0 nN (mean +/- SE, n = 12). Traction forces were exerted predominantly at the cell periphery and pointed to the cell center. Thrombin (1 U/ml) induced a fast and sustained 2.5-fold increase in traction forces, which maintained peripheral and centripetal distribution. Actin fluorescent staining revealed F-actin polymerization and enhancement of peripheral actin rim. Disruption of actin cytoskeleton with cytochalasin D (5 microM, 30 min) and inhibition of myosin light chain kinase with ML-7 (10 microM, 30 min) and Rho kinase with Y-27632 (10 microM, 30 min) markedly depressed basal contractile tone and abolished thrombin-induced cell contraction. Therefore, the contractile response of alveolar epithelial cells to the inflammatory agonist thrombin was mediated by actin cytoskeleton remodeling and actomyosin activation through myosin light chain kinase and Rho kinase signaling pathways. Thrombin-induced contractile tension might further impair alveolar epithelial barrier integrity in the injured lung. PMID:16675616

  19. A new model of tethered cord syndrome produced by slow traction

    PubMed Central

    Huang, Sheng-Li; Peng, Jun; Yuan, Guo-Lian; Ding, Xiao-Yan; He, Xi-Jing; Lan, Bin-Shang

    2015-01-01

    The development of a suitable animal model is important for clarifying the pathogenesis of tethered cord syndrome (TCS). This study was undertaken to develop a new animal model for investigating the pathogenesis and therapeutic strategies for TCS. A traction device, a filum terminale tractor, was designed exclusively for this experiment. A TCS model was produced in cats using the tractor to fixate the filum terminale to the dorsal aspect of the second sacrum. The responses to tethering were evaluated by electron microscopy and electromyography for detection of somatosensory evoked potentials (SEPs) and motor evoked potentials (MEPs) at designated time points. Progressive swaying gait and lameness in clinical performance were observed with cord traction. Histopathological examination revealed an association between the increasing traction in the spinal cord and the increase in impaired nerve cells. No changes of SEPs and MEPs were detected in the untethered cats, while the latencies of SEPs and MEPs significantly increased in the tethered cats. The TCS model established in this study is simple and reproducible, in which varying degrees of tension could be applied to the neural elements. PMID:25766487

  20. The wall traction induced by flowing red blood cells in model microvessels and its potential mechanotransduction

    NASA Astrophysics Data System (ADS)

    Freund, Jonathan; Vermot, Julien

    2013-11-01

    There is evidence in early embryonic development, even well before advective oxygen transport is important, that the presence of red bloods cells per se trigger essential steps of normal vascular development. For example, showed that sequestration of blood cells early in the development of a mouse, such that the hematocrit is reduced, suppresses normal vascular network development. Vascular development also provides a model for remodeling and angiogenesis. We consider the transient stresses associated with blood cells flowing in model microvessels of comparable diameter to those at early stages of development (6 μm to 12 μm). A detailed simulation tool is used to show that passing blood cells present a significant fluctuating traction signature on the vessel wall, well above the mean stresses. This is particularly pronounced for slow flows (<= 50 μm/s) or small diameters (<= 7 μm), for which root-mean-square wall traction fluctuations can exceed their mean. These events potentially present mechanotranduction triggers that direct development or remodeling. Attenuation of such fluctuating tractions by a viscoelastic endothelial glycocalyx layer is also considered. NSF supported.

  1. Simultaneous Application of Fibrous Piezoresistive Sensors for Compression and Traction Detection in Glass Laminate Composites

    PubMed Central

    Nauman, Saad; Cristian, Irina; Koncar, Vladan

    2011-01-01

    This article describes further development of a novel Non Destructive Evaluation (NDE) approach described in one of our previous papers. Here these sensors have been used for the first time as a Piecewise Continuous System (PCS), which means that they are not only capable of following the deformation pattern but can also detect distinctive fracture events. In order to characterize the simultaneous compression and traction response of these sensors, multilayer glass laminate composite samples were prepared for 3-point bending tests. The laminate sample consisted of five layers of plain woven glass fabrics placed one over another. The sensors were placed at two strategic locations during the lay-up process so as to follow traction and compression separately. The reinforcements were then impregnated in epoxy resin and later subjected to 3-point bending tests. An appropriate data treatment and recording device has also been developed and used for simultaneous data acquisition from the two sensors. The results obtained, under standard testing conditions have shown that our textile fibrous sensors can not only be used for simultaneous detection of compression and traction in composite parts for on-line structural health monitoring but their sensitivity and carefully chosen location inside the composite ensures that each fracture event is indicated in real time by the output signal of the sensor. PMID:22163707

  2. Characterization of Intracellular Streaming and Traction Forces in Migrating Physarum Plasmodia

    NASA Astrophysics Data System (ADS)

    Zhang, Shun; Meili, Ruedi; Guy, Robert D.; Lasheras, Juan C.; Del Alamo, Juan C.

    2013-11-01

    Physarum plasmodium is a model organism for cell migration that exhibits fast intracellular streaming. Single amoebae were seeded and allowed to move on polyacrilamide gels that contained 0.2 μm fluorescent beads. Joint time-lapse sequences of intracellular streaming and gel deformation were acquired respectively in the bright and fluorescent fields of a confocal microscope. Images were analyzed using particle image velocimetry (PIV) algorithms, and the traction stresses applied by the amoebae on the surface were computed by solving the elastostatic equation for the gel. These measurements provide, for the first time, a joint characterization of intracellular mass transport and the forces applied on the substrate of motile amoeboid cells with high resolution in both time and space, enables a through study about the locomotive mechanism and the relation between intracellular flow and traction stress, shedding light on related biomimetic research. The results reveal a pronounced auto-oscillation character in intracellular flow, contact area, centroid speed and strain energy, all with the same periodicity about 60 seconds. Adhesion sites are found to be almost stationary while a traction wave propagates from the tail to the anterior region in each cycle.

  3. Degradation-mediated cellular traction directs stem cell fate in covalently crosslinked three-dimensional hydrogels

    NASA Astrophysics Data System (ADS)

    Khetan, Sudhir; Guvendiren, Murat; Legant, Wesley R.; Cohen, Daniel M.; Chen, Christopher S.; Burdick, Jason A.

    2013-05-01

    Although cell-matrix adhesive interactions are known to regulate stem cell differentiation, the underlying mechanisms, in particular for direct three-dimensional encapsulation within hydrogels, are poorly understood. Here, we demonstrate that in covalently crosslinked hyaluronic acid (HA) hydrogels, the differentiation of human mesenchymal stem cells (hMSCs) is directed by the generation of degradation-mediated cellular traction, independently of cell morphology or matrix mechanics. hMSCs within HA hydrogels of equivalent elastic moduli that permit (restrict) cell-mediated degradation exhibited high (low) degrees of cell spreading and high (low) tractions, and favoured osteogenesis (adipogenesis). Moreover, switching the permissive hydrogel to a restrictive state through delayed secondary crosslinking reduced further hydrogel degradation, suppressed traction, and caused a switch from osteogenesis to adipogenesis in the absence of changes to the extended cellular morphology. Furthermore, inhibiting tension-mediated signalling in the permissive environment mirrored the effects of delayed secondary crosslinking, whereas upregulating tension induced osteogenesis even in the restrictive environment.

  4. Simultaneous application of fibrous piezoresistive sensors for compression and traction detection in glass laminate composites.

    PubMed

    Nauman, Saad; Cristian, Irina; Koncar, Vladan

    2011-01-01

    This article describes further development of a novel Non Destructive Evaluation (NDE) approach described in one of our previous papers. Here these sensors have been used for the first time as a Piecewise Continuous System (PCS), which means that they are not only capable of following the deformation pattern but can also detect distinctive fracture events. In order to characterize the simultaneous compression and traction response of these sensors, multilayer glass laminate composite samples were prepared for 3-point bending tests. The laminate sample consisted of five layers of plain woven glass fabrics placed one over another. The sensors were placed at two strategic locations during the lay-up process so as to follow traction and compression separately. The reinforcements were then impregnated in epoxy resin and later subjected to 3-point bending tests. An appropriate data treatment and recording device has also been developed and used for simultaneous data acquisition from the two sensors. The results obtained, under standard testing conditions have shown that our textile fibrous sensors can not only be used for simultaneous detection of compression and traction in composite parts for on-line structural health monitoring but their sensitivity and carefully chosen location inside the composite ensures that each fracture event is indicated in real time by the output signal of the sensor. PMID:22163707

  5. Baseline tests of the Volkswagen transporter electric delivery van

    NASA Technical Reports Server (NTRS)

    Soltis, R. F.; Mcbrien, E. F.; Bozek, J. M.; Gourash, F.

    1978-01-01

    The Volkswagen Transporter, an electric delivery van, was tested as part of an Energy Research and Development Administration (ERDA) project to characterize the state of the art of electric vehicles. The Volkswagen Transporter is a standard Volkswagen van that has been converted to an electric vehicle. It is powered by a 144-volt traction battery. A direct current (dc) chopper controller, actuated by a conventional accelerator pedal, regulates the voltage or power applied to the 16-kilowatt (21-hp) motor. The braking system uses conventional hydraulic braking in combination with an electric regenerative braking system. The Volkswagen vehicle performance test results are presented.

  6. Comparison between effectiveness of Mechanical and Manual Traction combined with mobilization and exercise therapy in Patients with Cervical Radiculopathy

    PubMed Central

    Bukhari, Syed Rehan Iftikhar; Shakil-ur-Rehman, Syed; Ahmad, Shakeel; Naeem, Aamer

    2016-01-01

    Background and Objective: Cervical radiculopathy is a common neuro-musculo-skeletal disorder causing pain and disability. Traction is part of the evidence based manual physical therapy management due to its mechanical nature, type of traction and parameters related to its applicability and are still to be explored more through research. Our objective was to determine the Effects of Mechanical versus Manual Traction in Manual Physical Therapy combined with segmental mobilization and exercise therapy in the physical therapy management of Patients with Cervical Radiculopathy. Methods: This randomized control trial was conducted at department of physical therapy and rehabilitation, Rathore Hospital Faisalabad, from February to July 2015. Inclusion criteria were both male and female patients with evident symptoms of cervical spine radiculopathy and age ranged between 20-70 years. The exclusion criteria were Patients with history of trauma, neck pain without radiculopathy, aged less than 20 and more than 70. A total of 72 patients with cervical radiculopathy were screened out as per the inclusion criteria, 42 patients were randomly selected and placed into two groups by toss and trial method, and only 36 patients completed the study, while 6 dropped out. The mechanical traction was applied in group A and manual traction in group B along with common intervention of segmental mobilization and exercise therapy in both groups for 6 weeks. The patient’s outcomes were assessed by self reported NPRS and NDI at the baseline and after completion of 06 weeks exercise program at 3 days per week. The data was analyzed through SPSS version-21, and paired T test was applied at 95% level significance to determine the statistical deference between two groups. Results: Clinically the group of patients treated with mechanical traction managed pain (mean pre 6.26, mean post 1.43), and disability (mean pre 24.43 and mean post 7.26) more effectively as compared with the group of patients

  7. Active Traction Force Response to Long-Term Cyclic Stretch Is Dependent on Cell Pre-stress.

    PubMed

    Cirka, Heather; Monterosso, Melissa; Diamantides, Nicole; Favreau, John; Wen, Qi; Billiar, Kristen

    2016-04-26

    Mechanical stimulation is recognized as a potent modulator of cellular behaviors such as proliferation, differentiation, and extracellular matrix assembly. However, the study of how cell-generated traction force changes in response to stretch is generally limited to short-term stimulation. The goal of this work is to determine how cells actively alter their traction force in response to long-term physiological cyclic stretch as a function of cell pre-stress. We have developed, to our knowledge, a novel method to assess traction force after long-term (24 h) uniaxial or biaxial cyclic stretch under conditions of high cell pre-stress with culture on stiff (7.5 kPa) polyacrylamide gels (with or without transforming growth factor β1 (TGF-β1)) and low pre-stress by treating with blebbistatin or culture on soft gels (0.6 kPa). In response to equibiaxial stretch, valvular interstitial cells on stiff substrates decreased their traction force (from 300 nN to 100 nN) and spread area (from 3000 to 2100 μm(2)). With uniaxial stretch, the cells had similar decreases in traction force and area and reoriented perpendicular to the stretch. TGF-β1-treated valvular interstitial cells had higher pre-stress (1100 nN) and exhibited a larger drop in traction force with uniaxial stretch, but the percentage changes in force and area with stretch were similar to the non-TGF-β1-treated group. Cells with inhibited myosin II motors increased traction force (from 41 nN to 63 nN) and slightly reoriented toward the stretch direction. In contrast, cells cultured on soft gels increased their traction force significantly, from 15 nN to 45 nN, doubled their spread area, elongated from an initially rounded morphology, and reoriented perpendicular to the uniaxial stretch. Contractile-moment measurements provided results consistent with total traction force measurements. The combined results indicate that the change in traction force in response to external cyclic stretch is dependent upon the

  8. The Affordable Care Act: a primer for plastic surgeons.

    PubMed

    Chen, Jenny T; Israel, Jacqueline S; Poore, Samuel O; Rao, Venkat K

    2014-11-01

    The Patient Protection and Affordable Care Act, sometimes referred to as Obamacare, was signed into law on March 23, 2010. It represents the most extensive overhaul of the country's health care system since the passage of Medicare and Medicaid in 1965. The Affordable Care Act has two goals. The first goal is to reduce the uninsured population in the United States. Key elements to covering the uninsured include the following: (1) expanding Medicaid coverage for low-income individuals and (2) establishing health insurance marketplaces for moderate-income individuals with subsidies and tax cuts in an effort to make health insurance more affordable. The second goal of the Affordable Care Act is to address concerns about quality and the overall cost of U.S. health care. It is imperative that plastic surgeons thoroughly understand the impact that the Affordable Care Act will undoubtedly have on the country, on our patients, and on our clinical practices. Plastic surgery will see many changes in the future. This will include an overall increase in the number of insured patients, a push toward joining accountable care organizations, and a shift in payment systems to bundled reimbursement for episodes of care. In this article, the authors describe how these changes are likely to occur and what plastic surgeons must do to be part of the change.

  9. The Affordance Template ROS Package for Robot Task Programming

    NASA Technical Reports Server (NTRS)

    Hart, Stephen; Dinh, Paul; Hambuchen, Kimberly

    2015-01-01

    This paper introduces the Affordance Template ROS package for quickly programming, adjusting, and executing robot applications in the ROS RViz environment. This package extends the capabilities of RViz interactive markers by allowing an operator to specify multiple end-effector waypoint locations and grasp poses in object-centric coordinate frames and to adjust these waypoints in order to meet the run-time demands of the task (specifically, object scale and location). The Affordance Template package stores task specifications in a robot-agnostic XML description format such that it is trivial to apply a template to a new robot. As such, the Affordance Template package provides a robot-generic ROS tool appropriate for building semi-autonomous, manipulation-based applications. Affordance Templates were developed by the NASA-JSC DARPA Robotics Challenge (DRC) team and have since successfully been deployed on multiple platforms including the NASA Valkyrie and Robonaut 2 humanoids, the University of Texas Dreamer robot and the Willow Garage PR2. In this paper, the specification and implementation of the affordance template package is introduced and demonstrated through examples for wheel (valve) turning, pick-and-place, and drill grasping, evincing its utility and flexibility for a wide variety of robot applications.

  10. Affordability Engineering: Bridging the Gap Between Design and Cost

    NASA Technical Reports Server (NTRS)

    Reeves, J. D.; DePasquale, Dominic; Lim, Evan

    2010-01-01

    Affordability is a commonly used term that takes on numerous meanings depending on the context used. Within conceptual design of complex systems, the term generally implies comparisons between expected costs and expected resources. This characterization is largely correct, but does not convey the many nuances and considerations that are frequently misunderstood and underappreciated. In the most fundamental sense, affordability and cost directly relate to engineering and programmatic decisions made throughout development programs. Systems engineering texts point out that there is a temporal aspect to this relationship, for decisions made earlier in a program dictate design implications much more so than those made during latter phases. This paper explores affordability engineering and its many sub-disciplines by discussing how it can be considered an additional engineering discipline to be balanced throughout the systems engineering and systems analysis processes. Example methods of multidisciplinary design analysis with affordability as a key driver will be discussed, as will example methods of data visualization, probabilistic analysis, and other ways of relating design decisions to affordability results.

  11. The Affordable Care Act: a primer for plastic surgeons.

    PubMed

    Chen, Jenny T; Israel, Jacqueline S; Poore, Samuel O; Rao, Venkat K

    2014-11-01

    The Patient Protection and Affordable Care Act, sometimes referred to as Obamacare, was signed into law on March 23, 2010. It represents the most extensive overhaul of the country's health care system since the passage of Medicare and Medicaid in 1965. The Affordable Care Act has two goals. The first goal is to reduce the uninsured population in the United States. Key elements to covering the uninsured include the following: (1) expanding Medicaid coverage for low-income individuals and (2) establishing health insurance marketplaces for moderate-income individuals with subsidies and tax cuts in an effort to make health insurance more affordable. The second goal of the Affordable Care Act is to address concerns about quality and the overall cost of U.S. health care. It is imperative that plastic surgeons thoroughly understand the impact that the Affordable Care Act will undoubtedly have on the country, on our patients, and on our clinical practices. Plastic surgery will see many changes in the future. This will include an overall increase in the number of insured patients, a push toward joining accountable care organizations, and a shift in payment systems to bundled reimbursement for episodes of care. In this article, the authors describe how these changes are likely to occur and what plastic surgeons must do to be part of the change. PMID:25347659

  12. The Value of Full Correction: Achieving Excellent and Affordable Results.

    PubMed

    Kaplan, Julie Bass

    2016-01-01

    Patients often come to medical aesthetic offices with hopes to fully correct lost facial volume and achieve a natural appearance. Unfortunately, the cost per syringe of dermal filler can be a barrier to desired outcomes. Many aesthetic practitioners do the best they can with the amount of product the patient can afford, often falling short of the "wow" effect for the patient. This article describes what one office implemented to solve the conundrum of affordability while still allowing offices to cover its own financial realities. This tool can help patients achieve beautiful, natural, and affordable outcomes while helping offices advance in manufacturer's tiers, improve word-of-mouth advertising, and increase job satisfaction. PMID:27606585

  13. The Affordable Care Act: The Value of Systemic Disruption

    PubMed Central

    2013-01-01

    It is important to recognize the political and policy accomplishments of the Patient Protection and Affordable Care Act (ACA), anticipate its limitations, and use the levers it provides strategically to address the problems it does not resolve. Passage of the ACA broke the political logjam that long stymied national progress toward equitable, quality, universal, affordable health care. It extends coverage for the uninsured who are disproportionately low income and people of color, curbs health insurance abuses, and initiates improvements in the quality of care. However, challenges to affordability and cost control persist. Public health advocates should mobilize for coverage for abortion care and for immigrants, encourage public-sector involvement in negotiating health care prices, and counter disinformation by opponents on the right. PMID:23409911

  14. Conflict between object structural and functional affordances in peripersonal space.

    PubMed

    Kalénine, Solène; Wamain, Yannick; Decroix, Jérémy; Coello, Yann

    2016-10-01

    Recent studies indicate that competition between conflicting action representations slows down planning of object-directed actions. The present study aims to assess whether similar conflict effects exist during manipulable object perception. Twenty-six young adults performed reach-to-grasp and semantic judgements on conflictual objects (with competing structural and functional gestures) and non-conflictual objects (with similar structural and functional gestures) presented at difference distances in a 3D virtual environment. Results highlight a space-dependent conflict between structural and functional affordances. Perceptual judgments on conflictual objects were slower that perceptual judgments on non-conflictual objects, but only when objects were presented within reach. Findings demonstrate that competition between structural and functional affordances during object perception induces a processing cost, and further show that object position in space can bias affordance competition.

  15. Conflict between object structural and functional affordances in peripersonal space.

    PubMed

    Kalénine, Solène; Wamain, Yannick; Decroix, Jérémy; Coello, Yann

    2016-10-01

    Recent studies indicate that competition between conflicting action representations slows down planning of object-directed actions. The present study aims to assess whether similar conflict effects exist during manipulable object perception. Twenty-six young adults performed reach-to-grasp and semantic judgements on conflictual objects (with competing structural and functional gestures) and non-conflictual objects (with similar structural and functional gestures) presented at difference distances in a 3D virtual environment. Results highlight a space-dependent conflict between structural and functional affordances. Perceptual judgments on conflictual objects were slower that perceptual judgments on non-conflictual objects, but only when objects were presented within reach. Findings demonstrate that competition between structural and functional affordances during object perception induces a processing cost, and further show that object position in space can bias affordance competition. PMID:27327864

  16. Essential kinematic information, athletic experience, and affordance perception for others.

    PubMed

    Weast, Julie A; Walton, Ashley; Chandler, Braylen C; Shockley, Kevin; Riley, Michael A

    2014-06-01

    The present study investigated the role of different types of movement in affordance perception, as well as the influence of sports experience. Perception of another actor's maximum vertical jumping height and horizontal long-jumping distance was evaluated for basketball players, soccer players, and nonplayer controls after viewing point-light representations of the actors' movements. Perceptual reports were more accurate after jumping-related movements (walking and squatting) were viewed than after nonrelated movements (standing and twisting). Vertical jump reports were more accurate than horizontal jump reports. Basketball and soccer players demonstrated higher accuracy than did controls. This research establishes that point-light displays contain essential kinematic information sufficient to support accurate affordance perception, and athletes appear better attuned to kinematic information specifying affordances for others as a result of their sports experience.

  17. Training and certification of doctors of chiropractic in delivering manual cervical traction forces: Results of a longitudinal observational study.

    PubMed

    Gudavalli, Maruti Ram; Vining, Robert D; Salsbury, Stacie A; Goertz, Christine M

    2014-10-01

    Objective : Doctors of chiropractic (DCs) use manual cervical distraction to treat patients with neck pain. Previous research demonstrates variability in traction forces generated by different DCs. This article reports on a training protocol and monthly certification process using bioengineering technology to standardize cervical traction force delivery among clinicians. Methods : This longitudinal observational study evaluated a training and certification process for DCs who provided force-based manual cervical distraction during a randomized clinical trial. The DCs completed a 7-week initial training that included instructional lectures, observation, and guided practice by a clinical expert, followed by 3 hours of weekly practice sessions delivering the technique to asymptomatic volunteers who served as simulated patients. An instrument-modified table and computer software provided the DCs with real-time audible and visual feedback on the traction forces they generated and graphical displays of the magnitude of traction forces as a function of time immediately after the delivery of the treatment. The DCs completed monthly certifications on traction force delivery throughout the trial. Descriptive accounts of certification attempts are provided. Results : Two DCs achieved certification in traction force delivery over 10 consecutive months. No certification required more than 3 attempts at C5 and occiput contacts for 3 force ranges (0-20 N, 21-50 N, and 51-100 N). Conclusions : This study demonstrates the feasibility of a training protocol and certification process using bioengineering technology for training DCs to deliver manual cervical distraction within specified traction force ranges over a 10-month period. PMID:25237767

  18. The efficacy of a home-mechanical traction unit for patients with mild to moderate cervical osteoarthrosis: A pilot study

    PubMed Central

    Bagheripour, Batoul; Kamyab, Mojtaba; Azadinia, Fatemeh; Amiri, Ali; Akbari, Mohammad

    2016-01-01

    Background: Traction has been suggested to be an effective treatment for symptoms of neck disorder in patients with no contraindications. However, according to previous researches, the effectiveness of traction is controversial, particularly compared to other conservative treatments. This trial was conducted to evaluate the effect of sustained traction, using an over-the-door home cervical traction unit in combination with routine physical therapy on reducing cervical osteoarthrosis symptoms including neck pain, medication use and disability level compared to routine physical therapy alone. Methods: In this double- blinded pilot study with a pre-post test design and a control group, 20 women with mild to moderate osteoarthrosis were systematically assigned to the over-the-door home cervical traction (mean±SD age: 50.5±4.45yrs) or control groups (mean±SD age: 55.6±7.34yrs). Pain, level of disability, and drug consumption were evaluated before and after 10 sessions of intervention. Data were analyzed using parametric or non-parametric statistic including the paired-sample t-test, independent sample t-test, and Wilcoxon and Mann-Whitney u test for intra and inter groups comparison based on the Kolmogorov-Smirnov test results. Results: Patients in both groups showed a significant decrease in pain intensity and disability level (p<0.05). Despite the greater improvement in pain levels and disability in the experimental group compared to the controls, the differences were not significant (p>0.05). No significant differences were found in terms of drugs consumption within and between the groups at the end of the treatment (p>0.05). Conclusion: The results revealed that applying sustained traction using an over-the-door home cervical traction unit was not significantly superior to the routine physical therapy and ergonomic training to manage symptoms including neck pain and disability in a small group of mild to moderate cervical osteoarthrosis patients. PMID:27493930

  19. Training and certification of doctors of chiropractic in delivering manual cervical traction forces: Results of a longitudinal observational study

    PubMed Central

    Gudavalli, Maruti Ram; Vining, Robert D.; Salsbury, Stacie A.; Goertz, Christine M.

    2014-01-01

    Objective Doctors of chiropractic (DCs) use manual cervical distraction to treat patients with neck pain. Previous research demonstrates variability in traction forces generated by different DCs. This article reports on a training protocol and monthly certification process using bioengineering technology to standardize cervical traction force delivery among clinicians. Methods This longitudinal observational study evaluated a training and certification process for DCs who provided force-based manual cervical distraction during a randomized clinical trial. The DCs completed a 7-week initial training that included instructional lectures, observation, and guided practice by a clinical expert, followed by 3 hours of weekly practice sessions delivering the technique to asymptomatic volunteers who served as simulated patients. An instrument-modified table and computer software provided the DCs with real-time audible and visual feedback on the traction forces they generated and graphical displays of the magnitude of traction forces as a function of time immediately after the delivery of the treatment. The DCs completed monthly certifications on traction force delivery throughout the trial. Descriptive accounts of certification attempts are provided. Results Two DCs achieved certification in traction force delivery over 10 consecutive months. No certification required more than 3 attempts at C5 and occiput contacts for 3 force ranges (0–20 N, 21–50 N, and 51–100 N). Conclusions This study demonstrates the feasibility of a training protocol and certification process using bioengineering technology for training DCs to deliver manual cervical distraction within specified traction force ranges over a 10-month period. PMID:25237767

  20. Can Low-Income Americans Afford a Healthy Diet?

    PubMed

    Drewnowski, Adam; Eichelsdoerfer, Petra

    2010-11-01

    Many nutritional professionals believe that all Americans, regardless of income, have access to a nutritious diet of whole grains, lean meats, and fresh vegetables and fruit. In reality, food prices pose a significant barrier for many consumers who are trying to balance good nutrition with affordability. The Thrifty Food Plan (TFP), commonly cited as a model of a healthy low-cost diet, achieves cost goals by relaxing some nutrition constraints and by disregarding the usual eating habits of the American population. Diet optimization techniques, when sensitive to cost and social norms, can help identify affordable, good tasting, nutrient-rich foods that are part of the mainstream American diet.

  1. Approach to an Affordable and Sustainable Space Transportation System

    NASA Technical Reports Server (NTRS)

    McCleskey, Caey M.; Rhodes, R. E.; Robinson, J. W.; Henderson, E. M.

    2012-01-01

    This paper describes an approach and a general procedure for creating space transportation architectural concepts that are at once affordable and sustainable. Previous papers by the authors and other members of the Space Propulsion Synergy Team (SPST) focused on a functional system breakdown structure for an architecture and definition of high-payoff design techniques with a technology integration strategy. This paper follows up by using a structured process that derives architectural solutions focused on achieving life cycle affordability and sustainability. Further, the paper includes an example concept that integrates key design techniques discussed in previous papers. !

  2. 76 FR 20354 - Notice of Intent To Award Supplemental Affordable Care Act Funding

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-12

    ... Affordable Care Act Funding Notice of Intent to award supplemental Affordable Care Act funding to support...: Notice. SUMMARY: This notice provides public announcement of CDC's intent to use Affordable Care Act (ACA....'' Funding is appropriated under the Affordable Care Act (Pub. L. 111-148), Title IV, Section...

  3. 75 FR 77002 - Proposed Extension of Information Collection Request Submitted for Public Comment; Affordable...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-10

    ... for Public Comment; Affordable Care Act Internal Claims and Appeals and External Review Procedures for... Patient Protection and Affordable Care Act (Affordable Care Act) that are discussed below. A copy of the... collection requests (ICRs) contained in the rule described below that relates to the Affordable Care......

  4. Spontaneous Ankylosis of Occiput to C2 following Closed Traction and Halo Treatment of Atlantoaxial Rotary Fixation

    PubMed Central

    Krengel, Walter F.; Kim, Paul H.; Wiater, Brett

    2015-01-01

    Study Design Case report. Objective We report a case of spontaneous atlantoaxial rotatory fixation (AARF) presenting 9 months after onset in an 11-year-old boy. Methods This is a retrospective case report of spontaneous ankylosis of occiput to C2 following traction, manipulative reduction, and halo immobilization for refractory atlantoaxial rotatory fixation. Results The patient underwent traction followed by close manual reduction and placement of halo immobilization after 6 months of severe spontaneous-onset AARF that had been refractory to chiropractic manipulation and physical therapy. Imaging demonstrated dislocation of the left C1–C2 facet joint and remodeling changes of the C2 superior facet prior to reduction, followed by near complete reduction of the dislocation after manipulation and halo placement. Symptoms and clinical appearance were satisfactorily improved and the halo vest was removed after 3 months. At late follow-up, computed tomography demonstrated complete bony ankylosis of the occiput to C2. The patient was found to be HLA B27-positive, but he had no family history of ankylosing spondyloarthropathy or other joint symptoms. The underlying reasons for spontaneous fusion of the occiput to C2 could include the traction, HLA-B27-related spondyloarthropathy, or arthropathic changes caused by traction, reduction, the inciting insult, or immobilization. Conclusion When discussing treatment of childhood refractory AARF by traction, closed manipulation, and halo immobilization, the possibility of developing “spontaneous” ankylosis needs to be considered. PMID:26131392

  5. Spontaneous Ankylosis of Occiput to C2 following Closed Traction and Halo Treatment of Atlantoaxial Rotary Fixation.

    PubMed

    Krengel, Walter F; Kim, Paul H; Wiater, Brett

    2015-06-01

    Study Design Case report. Objective We report a case of spontaneous atlantoaxial rotatory fixation (AARF) presenting 9 months after onset in an 11-year-old boy. Methods This is a retrospective case report of spontaneous ankylosis of occiput to C2 following traction, manipulative reduction, and halo immobilization for refractory atlantoaxial rotatory fixation. Results The patient underwent traction followed by close manual reduction and placement of halo immobilization after 6 months of severe spontaneous-onset AARF that had been refractory to chiropractic manipulation and physical therapy. Imaging demonstrated dislocation of the left C1-C2 facet joint and remodeling changes of the C2 superior facet prior to reduction, followed by near complete reduction of the dislocation after manipulation and halo placement. Symptoms and clinical appearance were satisfactorily improved and the halo vest was removed after 3 months. At late follow-up, computed tomography demonstrated complete bony ankylosis of the occiput to C2. The patient was found to be HLA B27-positive, but he had no family history of ankylosing spondyloarthropathy or other joint symptoms. The underlying reasons for spontaneous fusion of the occiput to C2 could include the traction, HLA-B27-related spondyloarthropathy, or arthropathic changes caused by traction, reduction, the inciting insult, or immobilization. Conclusion When discussing treatment of childhood refractory AARF by traction, closed manipulation, and halo immobilization, the possibility of developing "spontaneous" ankylosis needs to be considered.

  6. Deletion of the cytoplasmic domain of N-cadherin reduces, but does not eliminate, traction force-transmission.

    PubMed

    Lee, Eliot; Ewald, Makena L; Sedarous, Mary; Kim, Timothy; Weyers, Brent W; Truong, Rose Hong; Yamada, Soichiro

    2016-09-30

    Collective migration of epithelial cells is an integral part of embryonic development, wound healing, tissue renewal and carcinoma invasion. While previous studies have focused on cell-extracellular matrix adhesion as a site of migration-driving, traction force-transmission, cadherin mediated cell-cell adhesion is also capable of force-transmission. Using a soft elastomer coated with purified N-cadherin as a substrate and a Hepatocyte Growth Factor-treated, transformed MDCK epithelial cell line as a model system, we quantified traction transmitted by N-cadherin-mediated contacts. On a substrate coated with purified extracellular domain of N-cadherin, cell surface N-cadherin proteins arranged into puncta. N-cadherin mutants (either the cytoplasmic deletion or actin-binding domain chimera), however, failed to assemble into puncta, suggesting the assembly of focal adhesion like puncta requires the cytoplasmic domain of N-cadherin. Furthermore, the cytoplasmic domain deleted N-cadherin expressing cells exerted lower traction stress than the full-length or the actin binding domain chimeric N-cadherin. Our data demonstrate that N-cadherin junctions exert significant traction stress that requires the cytoplasmic domain of N-cadherin, but the loss of the cytoplasmic domain does not completely eliminate traction force transmission.

  7. A stochastic description on the traction-separation law of an interface with non-covalent bonding

    NASA Astrophysics Data System (ADS)

    Wei, Yujie

    2014-10-01

    We formulate a stochastic description about the mechanical response of an interface composed of non-covalent bonds. In such interfaces, the evolution of bonding probability in response to deformation plays the central role in determining their traction-separation behavior. The model connects atomistic and molecular level bonding properties to meso-scale traction-separation relationship in an interface. In response to quasi-static loading, the traction-separation of a stochastic interface is the resultant of varying bonding probability as a function of separation, and the bonding probability follows the Boltzmann distribution. The quasi-static stochastic interface model is applied to understand the critical force while detaching a sphere from an infinite half space. We further show the kinetics of interfacial debonding in the context of the Bell model (1978) and two of its derivatives - the Evans-Richie model (1997) and the Freund model (2009). While subjected to constant force, an interface creeps and its separation-time curve shows typical characteristics seen during the creep of crystalline materials at high temperature. When we exert constant separation rate to an interface, interfacial traction shows strong rate-sensitivity with higher traction at faster separation rate. The model presented here may supply a guidance to bring the stochastic nature of interfacial debonding into theories on cracking initiation and growth during fatigue fracture.

  8. E-Cadherin-Dependent Stimulation of Traction Force at Focal Adhesions via the Src and PI3K Signaling Pathways

    PubMed Central

    Jasaitis, Audrius; Estevez, Maruxa; Heysch, Julie; Ladoux, Benoit; Dufour, Sylvie

    2012-01-01

    The interplay between cadherin- and integrin-dependent signals controls cell behavior, but the precise mechanisms that regulate the strength of adhesion to the extracellular matrix remains poorly understood. We deposited cells expressing a defined repertoire of cadherins and integrins on fibronectin (FN)-coated polyacrylamide gels (FN-PAG) and on FN-coated pillars used as a micro-force sensor array (μFSA), and analyzed the functional relationship between these adhesion receptors to determine how it regulates cell traction force. We found that cadherin-mediated adhesion stimulated cell spreading on FN-PAG, and this was modulated by the substrate stiffness. We compared S180 cells with cells stably expressing different cadherins on μFSA and found that traction forces were stronger in cells expressing cadherins than in parental cells. E-cadherin-mediated contact and mechanical coupling between cells are required for this increase in cell-FN traction force, which was not observed in isolated cells, and required Src and PI3K activities. Traction forces were stronger in cells expressing type I cadherins than in cells expressing type II cadherins, which correlates with our previous observation of a higher intercellular adhesion strength developed by type I compared with type II cadherins. Our results reveal one of the mechanisms whereby molecular cross talk between cadherins and integrins upregulates traction forces at cell-FN adhesion sites, and thus provide additional insight into the molecular control of cell behavior. PMID:22853894

  9. Inside the Virtual Classroom: Student Perspectives on Affordances and Limitations

    ERIC Educational Resources Information Center

    Falloon, Garry

    2012-01-01

    Research indicates learners studying at a distance can experience perceptions of isolation and lack of "belonging" and support, which can adversely affect their learning experience and performance. Recently, the advent of affordable, accessible and reliable high-speed broadband has meant that a whole new array of digital tools to support…

  10. Learning to Identify and Actualize Affordances in a New Tool

    ERIC Educational Resources Information Center

    Haines, Karen J.

    2015-01-01

    Keeping abreast of new technologies and the opportunities they offer is a challenge for inservice teachers (Blake, 2008; Egbert, Akasha, Huff, & Lee, 2011; Hanson-Smith, 2006; Hubbard, 2007; Robb, 2006). An important aspect of teacher learning about the use of technology is the ability to identify the affordances of new tools and how they can…

  11. 12 CFR 1291.12 - Affordable Housing Reserve Fund.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Affordable Housing Reserve Fund. (b) Use or commitment of funds. Approval of applications for AHP subsidies... year-end are deemed to be used or committed if, in combination with AHP subsidies that have been... highest scoring AHP application in the Bank's final funding period of the year for its...

  12. Monitoring the price and affordability of foods and diets globally.

    PubMed

    Lee, A; Mhurchu, C N; Sacks, G; Swinburn, B; Snowdon, W; Vandevijvere, S; Hawkes, C; L'abbé, M; Rayner, M; Sanders, D; Barquera, S; Friel, S; Kelly, B; Kumanyika, S; Lobstein, T; Ma, J; Macmullan, J; Mohan, S; Monteiro, C; Neal, B; Walker, C

    2013-10-01

    Food prices and food affordability are important determinants of food choices, obesity and non-communicable diseases. As governments around the world consider policies to promote the consumption of healthier foods, data on the relative price and affordability of foods, with a particular focus on the difference between 'less healthy' and 'healthy' foods and diets, are urgently needed. This paper briefly reviews past and current approaches to monitoring food prices, and identifies key issues affecting the development of practical tools and methods for food price data collection, analysis and reporting. A step-wise monitoring framework, including measurement indicators, is proposed. 'Minimal' data collection will assess the differential price of 'healthy' and 'less healthy' foods; 'expanded' monitoring will assess the differential price of 'healthy' and 'less healthy' diets; and the 'optimal' approach will also monitor food affordability, by taking into account household income. The monitoring of the price and affordability of 'healthy' and 'less healthy' foods and diets globally will provide robust data and benchmarks to inform economic and fiscal policy responses. Given the range of methodological, cultural and logistical challenges in this area, it is imperative that all aspects of the proposed monitoring framework are tested rigorously before implementation. PMID:24074213

  13. Can Canadian Seniors on Public Pensions Afford a Nutritious Diet?

    ERIC Educational Resources Information Center

    Green, Rebecca J.; Williams, Patricia L.; Johnson, C. Shanthi; Blum, Ilya

    2008-01-01

    This study examined whether Canada's public pensions (Old Age Security and Canada Pension Plan) provided adequate income for seniors living in Nova Scotia in 2005 to afford a basic nutritious diet. Monthly incomes were compared to essential monthly expenses for four household scenarios: (a) married couple, 80 years and 78 years, in urban Nova…

  14. The ICCE Framework: Framing Learning Experiences Afforded by Games

    ERIC Educational Resources Information Center

    Foster, Aroutis; Shah, Mamta

    2015-01-01

    There is a need for game-based learning frameworks that provide a lens for understanding learning experiences afforded in digital games. These frameworks should aim to facilitate game analyses, identification of learning opportunities, and support for learner experiences. This article uses the inquiry, communication, construction, and expression…

  15. Teaching Text Structure: Examining the Affordances of Children's Informational Texts

    ERIC Educational Resources Information Center

    Jones, Cindy D.; Clark, Sarah K.; Reutzel, D. Ray

    2016-01-01

    This study investigated the affordances of informational texts to serve as model texts for teaching text structure to elementary school children. Content analysis of a random sampling of children's informational texts from top publishers was conducted on text structure organization and on the inclusion of text features as signals of text…

  16. Disengaged Students and Dialogic Learning: The Role of CSCL Affordances

    ERIC Educational Resources Information Center

    Slakmon, Benzi; Schwarz, Baruch B.

    2014-01-01

    Only a few studies have dealt with the challenge of bridging the linguistic gap between the dialogic realm and the talk of disengaged students. Bridging this gap is particularly relevant to the CSCL community since one of its utmost aims is to promote the dialogic. This study aims to articulate how to harness the CSCL design and affordances to…

  17. The Weight of Time: Affordances for an Integrated Magnitude System

    ERIC Educational Resources Information Center

    Lu, Aitao; Mo, Lei; Hodges, Bert H.

    2011-01-01

    In five experiments we explored the effects of weight on time in different action contexts to test the hypothesis that an integrated magnitude system is tuned to affordances. Larger magnitudes generally seem longer; however, Lu and colleagues (2009) found that if numbers were presented as weights in a range heavy enough to affect lifting, the…

  18. 24 CFR 1006.201 - Eligible affordable housing activities.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 4 2012-04-01 2012-04-01 false Eligible affordable housing activities. 1006.201 Section 1006.201 Housing and Urban Development REGULATIONS RELATING TO HOUSING AND URBAN... URBAN DEVELOPMENT NATIVE HAWAIIAN HOUSING BLOCK GRANT PROGRAM Eligible Activities § 1006.201...

  19. 24 CFR 1006.201 - Eligible affordable housing activities.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Eligible affordable housing activities. 1006.201 Section 1006.201 Housing and Urban Development Regulations Relating to Housing and Urban... URBAN DEVELOPMENT NATIVE HAWAIIAN HOUSING BLOCK GRANT PROGRAM Eligible Activities § 1006.201...

  20. 24 CFR 1006.201 - Eligible affordable housing activities.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false Eligible affordable housing activities. 1006.201 Section 1006.201 Housing and Urban Development REGULATIONS RELATING TO HOUSING AND URBAN... URBAN DEVELOPMENT NATIVE HAWAIIAN HOUSING BLOCK GRANT PROGRAM Eligible Activities § 1006.201...

  1. 24 CFR 81.14 - Special Affordable Housing Goal.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... MAE) AND THE FEDERAL HOME LOAN MORTGAGE CORPORATION (FREDDIE MAC) Housing Goals § 81.14 Special..., as a Special Affordable Housing Home Purchase Subgoal, 17 percent of the total number of home purchase mortgages in metropolitan areas financed by each GSE's mortgage purchases shall be home...

  2. 24 CFR 81.14 - Special Affordable Housing Goal.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... MAE) AND THE FEDERAL HOME LOAN MORTGAGE CORPORATION (FREDDIE MAC) Housing Goals § 81.14 Special..., as a Special Affordable Housing Home Purchase Subgoal, 17 percent of the total number of home purchase mortgages in metropolitan areas financed by each GSE's mortgage purchases shall be home...

  3. 12 CFR 1282.14 - Special Affordable Housing Goal.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Fannie Mae and $4.60 billion for Freddie Mac. In addition, as a Special Affordable Housing Home Purchase Subgoal, 14 percent of the total number of home purchase mortgages in metropolitan areas financed by that Enterprise's mortgage purchases shall be home purchase mortgages in metropolitan areas which count toward...

  4. 24 CFR 954.307 - Homeownership: qualification as affordable housing.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... whose family qualifies as a low-income family at the time HOME funds are committed to the housing. ... HOUSING AND URBAN DEVELOPMENT INDIAN HOME PROGRAM Eligible Activities and Affordability § 954.307... (1- to 4-family residence, condominium unit, cooperative unit, combination manufactured home and...

  5. Lean, Mean and Green: An Affordable Net Zero School

    ERIC Educational Resources Information Center

    Stanfield, Kenneth

    2010-01-01

    From its conception, Richardsville Elementary was designed to be an affordable net zero facility. The design team explored numerous energy saving strategies to dramatically reduce energy consumption. By reducing energy use to 19.31 kBtus annually, the net zero goal could be realized through the implementation of a solar array capable of producing…

  6. Affordance, Learning Opportunities, and the Lesson Plan Pro Forma

    ERIC Educational Resources Information Center

    Anderson, Jason

    2015-01-01

    This article argues that the most commonly used lesson plan pro formas in language teacher education are inappropriately premised on an outcomes-based approach to teaching, one that is in conflict with what we know about how languages are learnt and how experienced teachers teach. It proposes an alternative, affordance-based approach to lesson…

  7. Reinventing Financial Aid: Charting a New Course to College Affordability

    ERIC Educational Resources Information Center

    Kelly, Andrew P., Ed.; Goldrick-Rab, Sara, Ed.

    2014-01-01

    In this provocative volume, two experts with very different points of view address the growing concern that student loan programs are not a sustainable solution to the problem of mounting college costs. They argue that the time has come to reform the financial aid system so that it is more effective in promoting college affordability, access, and…

  8. Pedagogical Affordances of Multiple External Representations in Scientific Processes

    NASA Astrophysics Data System (ADS)

    Wu, Hsin-Kai; Puntambekar, Sadhana

    2012-12-01

    Multiple external representations (MERs) have been widely used in science teaching and learning. Theories such as dual coding theory and cognitive flexibility theory have been developed to explain why the use of MERs is beneficial to learning, but they do not provide much information on pedagogical issues such as how and in what conditions MERs could be introduced and used to support students' engagement in scientific processes and develop competent scientific practices (e.g., asking questions, planning investigations, and analyzing data). Additionally, little is understood about complex interactions among scientific processes and affordances of MERs. Therefore, this article focuses on pedagogical affordances of MERs in learning environments that engage students in various scientific processes. By reviewing literature in science education and cognitive psychology and integrating multiple perspectives, this article aims at exploring (1) how MERs can be integrated with science processes due to their different affordances, and (2) how student learning with MERs can be scaffolded, especially in a classroom situation. We argue that pairing representations and scientific processes in a principled way based on the affordances of the representations and the goals of the activities is a powerful way to use MERs in science education. Finally, we outline types of scaffolding that could help effective use of MERs including dynamic linking, model progression, support in instructional materials, teacher support, and active engagement.

  9. Learning Affordances of Language and Communication National Curricula

    ERIC Educational Resources Information Center

    Scott, David

    2016-01-01

    This article focuses on the learning affordances of different language and communication curricula in the world. For reasons of space, only two national education systems (Finland and Singapore) and their language and communication curricula are referred to. The accounts of national education systems consist of the identification of mechanisms…

  10. Federal Home Visiting under the Affordable Care Act

    ERIC Educational Resources Information Center

    Strader, Kathleen; Counts, Jacqueline; Filene, Jill

    2013-01-01

    The Maternal, Infant, and Early Childhood Home Visiting (MIECHV) Program is part of The Patient Protection and Affordable Care Act and provides $1.5 billion over 5 years to states, territories, and tribes with the goal of delivering evidence-based home visiting services as part of a high-quality, comprehensive early childhood system that promotes…

  11. Conceptual and Physical Object Qualities Contribute Differently to Motor Affordances

    ERIC Educational Resources Information Center

    Vingerhoets, G.; Vandamme, K.; Vercammen, A.

    2009-01-01

    Priming studies have demonstrated that an object's intrinsic and extrinsic qualities (size, orientation) influence subsequent motor behavior thus suggesting that these object qualities "afford" actions that are congruent with the prime. We present four experiments that aim to evaluate the relative effect of conceptual and physical object qualities…

  12. Can the United States afford a lunar base

    NASA Technical Reports Server (NTRS)

    Keaton, Paul W.

    1988-01-01

    Establishing a lunar base will require steady funding for a decade or two. The question addressed is whether such a large space project is affordable at this time. The relevant facts and methodology are presented so that the reader may formulate independent answers. It is shown that a permanent lunar base can be financed without increasing NASA's historical budgetary trend.

  13. The ethics of the affordability of health insurance.

    PubMed

    Saloner, Brendan; Daniels, Norman

    2011-10-01

    In this essay we argue that the concept of affordable health insurance is rooted in a social obligation to protect fair equality of opportunity. Specifically, health insurance plays a limited but significant role in protecting opportunity in two ways: it helps keep people functioning normally and it protects their financial security. Together these benefits enable household members to exercise reasonable choices about their plans of life. To achieve truly affordable coverage, society must be able to contain the overall cost of health care, and health insurance must be progressively financed, meaning that those who are best able to pay for coverage should pay the largest share. While the recently passed Patient Protection and Affordable Care Act (ACA) falls short on both of these counts, we argue that it makes important contributions toward household affordability through the use of subsidies and regulations. The main shortcoming of the ACA is an insufficient protection against burdensome cost sharing, which we illustrate using several hypothetical scenarios. We conclude with recommendations about how to make opportunity-enhancing expansions to the current coverage subsidies.

  14. Affordances of Learning Technologies in Higher Education Multicultural Environments

    ERIC Educational Resources Information Center

    Arenas, Edilson

    2015-01-01

    A cluster of research has been conducted in higher education to investigate the affordances (action possibilities) and the influence information and communication technologies (ICT) may have on students' learning experiences and outcomes. Such studies have given rise to the implementation of a wide range of educational frameworks with a great deal…

  15. Affordances for Second Language Learning in "World of Warcraft"

    ERIC Educational Resources Information Center

    Rama, Paul S.; Black, Rebecca W.; van Es, Elizabeth; Warschauer, Mark

    2012-01-01

    What are the affordances of online gaming environments for second language learning and socialization? To answer this question, this qualitative study examines two college-age Spanish learners' experiences participating in the Spanish language version of the massively multi-player online game "World of Warcraft." Using data culled from participant…

  16. The ethics of the affordability of health insurance.

    PubMed

    Saloner, Brendan; Daniels, Norman

    2011-10-01

    In this essay we argue that the concept of affordable health insurance is rooted in a social obligation to protect fair equality of opportunity. Specifically, health insurance plays a limited but significant role in protecting opportunity in two ways: it helps keep people functioning normally and it protects their financial security. Together these benefits enable household members to exercise reasonable choices about their plans of life. To achieve truly affordable coverage, society must be able to contain the overall cost of health care, and health insurance must be progressively financed, meaning that those who are best able to pay for coverage should pay the largest share. While the recently passed Patient Protection and Affordable Care Act (ACA) falls short on both of these counts, we argue that it makes important contributions toward household affordability through the use of subsidies and regulations. The main shortcoming of the ACA is an insufficient protection against burdensome cost sharing, which we illustrate using several hypothetical scenarios. We conclude with recommendations about how to make opportunity-enhancing expansions to the current coverage subsidies. PMID:22065686

  17. 24 CFR 1006.201 - Eligible affordable housing activities.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... URBAN DEVELOPMENT NATIVE HAWAIIAN HOUSING BLOCK GRANT PROGRAM Eligible Activities § 1006.201 Eligible... 24 Housing and Urban Development 4 2014-04-01 2014-04-01 false Eligible affordable housing activities. 1006.201 Section 1006.201 Housing and Urban Development REGULATIONS RELATING TO HOUSING AND...

  18. 24 CFR 1006.201 - Eligible affordable housing activities.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Eligible affordable housing activities. 1006.201 Section 1006.201 Housing and Urban Development REGULATIONS RELATING TO HOUSING AND URBAN DEVELOPMENT (CONTINUED) OFFICE OF ASSISTANT SECRETARY FOR PUBLIC AND INDIAN HOUSING, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT NATIVE...

  19. 24 CFR 1006.20 - Grants for affordable housing activities.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Grants for affordable housing activities. 1006.20 Section 1006.20 Housing and Urban Development REGULATIONS RELATING TO HOUSING AND URBAN DEVELOPMENT (CONTINUED) OFFICE OF ASSISTANT SECRETARY FOR PUBLIC AND INDIAN HOUSING, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT NATIVE...

  20. Can the United States afford a lunar base

    NASA Astrophysics Data System (ADS)

    Keaton, Paul W.

    1988-03-01

    Establishing a lunar base will require steady funding for a decade or two. The question addressed is whether such a large space project is affordable at this time. The relevant facts and methodology are presented so that the reader may formulate independent answers. It is shown that a permanent lunar base can be financed without increasing NASA's historical budgetary trend.

  1. Voters and the Affordable Care Act in the 2014 election.

    PubMed

    Blendon, Robert J; Benson, John M

    2014-11-13

    In this analysis of data from 27 public opinion polls, the authors examine the role of the Affordable Care Act in the 2014 congressional elections. The outcome of the elections is likely to influence implementation of the ACA and future U.S. health care policy. PMID:25353968

  2. Access and Affordability: Strategic Financial Perspectives for Independent Schools.

    ERIC Educational Resources Information Center

    Aitken, H. Peter

    The challenge to independent schools is maintaining excellent facilities and instruction while providing access to students from the widest range of financial backgrounds possible. This is difficult when many independent schools struggle to balance their budgets. There is growing evidence that independent schools are becoming less affordable and…

  3. A Few Reflections on Accountability, Affordability, and Access Worldwide

    ERIC Educational Resources Information Center

    Toma, J. Douglas

    2008-01-01

    Considering accountability, affordability, and access through the experiences in Chile, East Asia, Australia, Croatia, and the United States offers a clear reminder that trends and issues in higher education are often more similar across national contexts than they are distinct. Across higher education, institutions and systems are responding to…

  4. 7 CFR 3565.352 - Preservation of affordable housing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Preservation of affordable housing. 3565.352 Section 3565.352 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, DEPARTMENT OF AGRICULTURE GUARANTEED RURAL RENTAL HOUSING PROGRAM Project Management § 3565.352...

  5. 7 CFR 3565.352 - Preservation of affordable housing.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 15 2012-01-01 2012-01-01 false Preservation of affordable housing. 3565.352 Section 3565.352 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, DEPARTMENT OF AGRICULTURE GUARANTEED RURAL RENTAL HOUSING PROGRAM Project Management § 3565.352...

  6. 7 CFR 3565.352 - Preservation of affordable housing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Preservation of affordable housing. 3565.352 Section 3565.352 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, DEPARTMENT OF AGRICULTURE GUARANTEED RURAL RENTAL HOUSING PROGRAM Project Management § 3565.352...

  7. 7 CFR 3565.352 - Preservation of affordable housing.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Preservation of affordable housing. 3565.352 Section 3565.352 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, DEPARTMENT OF AGRICULTURE GUARANTEED RURAL RENTAL HOUSING PROGRAM Project Management § 3565.352...

  8. 7 CFR 3565.352 - Preservation of affordable housing.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Preservation of affordable housing. 3565.352 Section 3565.352 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, DEPARTMENT OF AGRICULTURE GUARANTEED RURAL RENTAL HOUSING PROGRAM Project Management § 3565.352...

  9. 24 CFR 81.14 - Special Affordable Housing Goal.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 1 2013-04-01 2013-04-01 false Special Affordable Housing Goal. 81.14 Section 81.14 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development THE SECRETARY OF HUD'S REGULATION OF THE FEDERAL NATIONAL MORTGAGE ASSOCIATION...

  10. 24 CFR 81.14 - Special Affordable Housing Goal.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 1 2012-04-01 2012-04-01 false Special Affordable Housing Goal. 81.14 Section 81.14 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development THE SECRETARY OF HUD'S REGULATION OF THE FEDERAL NATIONAL MORTGAGE ASSOCIATION...

  11. 24 CFR 81.14 - Special Affordable Housing Goal.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 1 2014-04-01 2014-04-01 false Special Affordable Housing Goal. 81.14 Section 81.14 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development THE SECRETARY OF HUD'S REGULATION OF THE FEDERAL NATIONAL MORTGAGE ASSOCIATION...

  12. Abduction and Affordance: A Semiotic View of Cognition.

    ERIC Educational Resources Information Center

    Cunningham, Donald J.

    The shortcomings of the dominant information processing models of cognition are outlined, and two alterative models derived from semiotics are presented. In addition, the possibility of incorporating J. J. Gibson's ecological theory of affordance within the semiotic models is explored as a means of addressing some criticism of the latter models.…

  13. The Affordability Challenge in California Higher Education: Options for Change

    ERIC Educational Resources Information Center

    California Postsecondary Education Commission, 2007

    2007-01-01

    California's Master Plan for Higher Education represented a promise, of an affordable college education, to every person who could benefit. For decades, California's lawmakers honored that promise. Rapidly increasing college fees, coupled with higher costs for room and board, books, transportation, and healthcare are pricing students out of higher…

  14. Learning at Work: Organisational Affordances and Individual Engagement

    ERIC Educational Resources Information Center

    Bryson, Jane; Pajo, Karl; Ward, Robyn; Mallon, Mary

    2006-01-01

    Purpose: The purpose of this research is to explore the interaction between organisational affordances for the development of individuals' capability, and the engagement of workers at various levels with those opportunities. Design/methodology/approach: A case study of a large New Zealand wine company, using in-depth interviews. Interviews were…

  15. Material Affordances: The Potential of Scrapbooks in the Composition Classroom

    ERIC Educational Resources Information Center

    Alexander, Kara Poe

    2013-01-01

    A multiliteracies pedagogy has renewed our interest in materiality, or how the physical text interacts with the author's choices and the context to contribute to the message, yet little attention has been paid to materiality in analog texts, such as the scrapbook, even though this medium contains affordances (capabilities and limitations) that…

  16. Early Visual Perception Potentiated by Object Affordances: Evidence From a Temporal Order Judgment Task

    PubMed Central

    Yamada, Yuki; Yamani, Yusuke

    2016-01-01

    Perceived objects automatically potentiate afforded action. Object affordances also facilitate perception of such objects, and this occurrence is known as the affordance effect. This study examined whether object affordances facilitate the initial visual processing stage, or perceptual entry processes, using the temporal order judgment task. The onset of the graspable (right-handled) coffee cup was perceived earlier than that of the less graspable (left-handled) cup for right-handed participants. The affordance effect was eliminated when the coffee cups were inverted, which presumably conveyed less affordance information. These results suggest that objects preattentively potentiate the perceptual entry processes in response to their affordances.

  17. Vitrectomy Outcomes in Eyes with Diabetic Macular Edema and Vitreomacular Traction

    PubMed Central

    2010-01-01

    Purpose To evaluate vitrectomy for diabetic macular edema (DME) in eyes with at least moderate vision loss and vitreomacular traction. Design Prospective cohort study Participants The primary cohort included 87 eyes with DME and vitreomacular traction based on investigator’s evaluation, visual acuity 20/63–20/400, optical coherence tomography (OCT) central subfield >300 microns and no concomitant cataract extraction at the time of vitrectomy. Methods Surgery was performed according to the investigator’s usual routine. Follow-up visits were performed after 3 months, 6 months (primary endpoint) and 1 year. Main Outcome Measures Visual acuity, OCT retinal thickening and surgical complications. Results At baseline, median visual acuity in the 87 eyes was 20/100 and median OCT thickness was 491 microns. During vitrectomy, additional procedures included epiretinal membrane peeling in 61%, internal limiting membrane peeling in 54%, panretinal photocoagulation in 40% and injection of corticosteroids at the close of the procedure in 64%. At 6 months, median OCT central subfield thickness decreased by 160 microns, with 43% having central subfield thickness <250 microns and 68% having at least a 50% reduction in thickening. Visual acuity improved by 10 or more letters in 38% (95% confidence interval 28% – 49%) and deteriorated by 10 or more letters in 22% (95% confidence interval 13% – 31%). Postoperative surgical complications through 6 months included vitreous hemorrhage (5 eyes), elevated intraocular pressure requiring treatment (7 eyes), retinal detachment (3 eyes) and endophthalmitis (1 eye). Little changes in results were noted between 6 months and one year. Conclusion Following vitrectomy performed for DME and vitreomacular traction, retinal thickening was reduced in most eyes. Between 28% and 49% of eyes with characteristics similar to those included in this study are likely to have improvement of visual acuity, while between 13% and 31% are likely to have

  18. Traction-drive, seven-degree-of-freedom telerobot arm: A concept for manipulaton in space

    NASA Technical Reports Server (NTRS)

    Kuban, D. P.; Williams, D. M.

    1987-01-01

    As man seeks to expand his dominion into new environments, the demand increases for machines that perform useful functions in remote locations. This new concept for manipulation in space is based on knowledge and experience gained from manipulator systems developed to meet the needs of remote nuclear applications. It merges the best characteristics of teleoperation and robotic technologies. The design goals for the telerobot, a mechanical description, and technology areas that must be addressed for successful implementation are presented and discussed. The concept incorporates mechanical traction drives, redundant kinematics, and modular arm subelements to provide a backlash-free manipulator capable of obstacle avoidance.

  19. University Tuition, Consumer Choice and College Affordability: Strategies for Addressing a Higher Education Affordability Challenge. A NASULGC Discussion Paper

    ERIC Educational Resources Information Center

    McPherson, Peter; Shulenburger, David

    2008-01-01

    With passage of the Higher Education Opportunity Act of 2008, the Higher Education Act (HEA) is now reauthorized. What effect will it have on U.S. higher education? Students receiving Pell grants will find that college is more affordable while those who feared that the government would exert control over learning outcomes have breathed a…

  20. [Three-dimensional optical coherence tomography for evaluating the retinal architecture before and after surgery for vitreomacular traction.

    PubMed

    Georgopoulos, M; Geitzenauer, W; Ahlers, C; Simader, C; Scholda, C; Schmidt-Erfurth, U

    2008-03-30

    PURPOSE: To investigate the morphology of the vitreoretinal interface before and after delamination of epiretinal membranes using three-dimensional volumetric high-resolution optical coherence tomography (HROCT). METHODS: Extension and intensity of vitreomacular traction due to epiretinal membranes (ERM) and the architecture of retinal layers in 14 eyes of 14 patients were evaluated preoperatively using high-resolution raster scanning OCT (Cirrus prototype, resulting in a 6x6-mm field, 2 mm in depth). Additionally, stratus OCT, visual acuity testing, and fundus photography were performed. Standardized prospective follow-up was done continuously at 1, 4, and 7 days and 1 and 3 months postoperatively. RESULTS: The ERM appeared tightly adherent to the retinal surface in 85% of cases, but nevertheless could be differentiated from the retinal surface in 100%. Vertical traction forces from the ERM to the intraretinal layers were found in 93% of cases. Structural alteration of the retina was seen neither immediately following surgery nor during follow-up. After a mean of 4 weeks, the retinal structural integrity had recovered with resolution of the traction-induced deviations seen preoperatively. Mean preoperative visual acuity increased from 0.4+/-0.2 Snellen preoperatively to 0.5+/-0.2 Snellen after 3 months. Mean retinal thickness decreased from 482+/-84 mum to 328+/-80 mum after 3 months (HROCT). CONCLUSIONS: Three-dimensional HROCT imaging enables unprecedented in vivo identification of the extension and dynamics of epiretinal traction. Epiretinal membranes are clearly delineated in the en face view, and the distribution of traction forces throughout the intraretinal layers is identified down to the level of the retinal pigment epithelium. During follow-up, quantification of substantial release in retinal traction was possible and correlated to conventional OCT findings.

  1. Electrically conductive material

    DOEpatents

    Singh, J.P.; Bosak, A.L.; McPheeters, C.C.; Dees, D.W.

    1993-09-07

    An electrically conductive material is described for use in solid oxide fuel cells, electrochemical sensors for combustion exhaust, and various other applications possesses increased fracture toughness over available materials, while affording the same electrical conductivity. One embodiment of the sintered electrically conductive material consists essentially of cubic ZrO[sub 2] as a matrix and 6-19 wt. % monoclinic ZrO[sub 2] formed from particles having an average size equal to or greater than about 0.23 microns. Another embodiment of the electrically conductive material consists essentially at cubic ZrO[sub 2] as a matrix and 10-30 wt. % partially stabilized zirconia (PSZ) formed from particles having an average size of approximately 3 microns. 8 figures.

  2. Electrically conductive material

    DOEpatents

    Singh, Jitendra P.; Bosak, Andrea L.; McPheeters, Charles C.; Dees, Dennis W.

    1993-01-01

    An electrically conductive material for use in solid oxide fuel cells, electrochemical sensors for combustion exhaust, and various other applications possesses increased fracture toughness over available materials, while affording the same electrical conductivity. One embodiment of the sintered electrically conductive material consists essentially of cubic ZrO.sub.2 as a matrix and 6-19 wt. % monoclinic ZrO.sub.2 formed from particles having an average size equal to or greater than about 0.23 microns. Another embodiment of the electrically conductive material consists essentially at cubic ZrO.sub.2 as a matrix and 10-30 wt. % partially stabilized zirconia (PSZ) formed from particles having an average size of approximately 3 microns.

  3. Supercapacitors for the energy management of electric vehicles

    NASA Astrophysics Data System (ADS)

    Faggioli, Eugenio; Rena, Piergeorgio; Danel, Veronique; Andrieu, X.; Mallant, Ronald; Kahlen, Hans

    The integration of the on-board energy source of an electrically propelled vehicle with a supercapacitor bank (SB) as a peak power unit, can lead to substantial benefits in terms of electric vehicle performances, battery life and energy economy. Different architectures may be envisaged, to be chosen according to technical-economical trade-off. A research activity, supported by the European Community in the frame of the Joule III program and titled `Development of Supercapacitors for Electric Vehicles' (contract JOE3-CT95-0001), has been in progress since the beginning of 1996. The partners involved are SAFT (project leader), Alcatel Alsthom Research (France), Centro Ricerche Fiat (Italy), University of Kaiserslautern (Germany), Danionics (DK) and ECN (Netherlands). Its objective is to develop a SB and its electronic control and to integrate them in two different full-scale traction systems, supplied, respectively, by sealed lead traction batteries and by a fuel cell system. Through the bench tests, it will be possible to evaluate the impact of the SB on both traction systems. In this paper, a project overview will be given; the power management strategy principles, the supercapacitor's control electronic devices, the system's architecture and the supercapacitor's requirements on the base of the simulation results, will be examined.

  4. Elastic response of DNA molecules under the action of interfacial traction and stretching: An elastic thin rod model

    NASA Astrophysics Data System (ADS)

    Xiao, Ye; Huang, Zaixing; Qiang, Lei; Gao, Jun

    2015-11-01

    In a multivalent salt solution, a segment of DNA is modeled as an elastic rod subjected to the interfacial traction. The shooting method is used to calculate the equilibrium configurations of condensed DNA under the action of the longitudinal end-force and interfacial traction simultaneously. The results show that the shapes of DNA are mainly determined by the competition between the interfacial energy and elastic strain energy of stretching. The change of end-to-end distance with the longitudinal end-force is consistent with the worm-like chain (WLC) model. The higher the concentration is, the stronger the condensation of DNA.

  5. Integrated Inverter For Driving Multiple Electric Machines

    DOEpatents

    Su, Gui-Jia [Knoxville, TN; Hsu, John S [Oak Ridge, TN

    2006-04-04

    An electric machine drive (50) has a plurality of inverters (50a, 50b) for controlling respective electric machines (57, 62), which may include a three-phase main traction machine (57) and two-phase accessory machines (62) in a hybrid or electric vehicle. The drive (50) has a common control section (53, 54) for controlling the plurality of inverters (50a, 50b) with only one microelectronic processor (54) for controlling the plurality of inverters (50a, 50b), only one gate driver circuit (53) for controlling conduction of semiconductor switches (S1-S10) in the plurality of inverters (50a, 50b), and also includes a common dc bus (70), a common dc bus filtering capacitor (C1) and a common dc bus voltage sensor (67). The electric machines (57, 62) may be synchronous machines, induction machines, or PM machines and may be operated in a motoring mode or a generating mode.

  6. Modeling the mechanics of cells in the cell-spreading process driven by traction forces

    NASA Astrophysics Data System (ADS)

    Fang, Yuqiang; Lai, King W. C.

    2016-04-01

    Mechanical properties of cells and their mechanical interaction with the extracellular environments are main factors influencing cellular function, thus indicating the progression of cells in different disease states. By considering the mechanical interactions between cell adhesion molecules and the extracellular environment, we developed a cell mechanical model that can characterize the mechanical changes in cells during cell spreading. A cell model was established that consisted of various main subcellular components, including cortical cytoskeleton, nuclear envelope, actin filaments, intermediate filaments, and microtubules. We demonstrated the structural changes in subcellular components and the changes in spreading areas during cell spreading driven by traction forces. The simulation of nanoindentation tests was conducted by integrating the indenting force to the cell model. The force-indentation curve of the cells at different spreading states was simulated, and the results showed that cell stiffness increased with increasing traction forces, which were consistent with the experimental results. The proposed cell mechanical model provides a strategy to investigate the mechanical interactions of cells with the extracellular environments through the adhesion molecules and to reveal the cell mechanical properties at the subcellular level as cells shift from the suspended state to the adherent state.

  7. Geometric guidance of integrin mediated traction stress during stem cell differentiation.

    PubMed

    Lee, Junmin; Abdeen, Amr A; Tang, Xin; Saif, Taher A; Kilian, Kristopher A

    2015-11-01

    Cells sense and transduce the chemical and mechanical properties of their microenvironment through cell surface integrin receptors. Traction stress exerted by cells on the extracellular matrix mediates focal adhesion stabilization and regulation of the cytoskeleton for directing biological activity. Understanding how stem cells integrate biomaterials properties through focal adhesions during differentiation is important for the design of soft materials for regenerative medicine. In this paper we use micropatterned hydrogels containing fluorescent beads to explore force transmission through integrins from single mesenchymal stem cells (MSCs) during differentiation. When cultured on polyacrylamide gels, MSCs will express markers associated with osteogenesis and myogenesis in a stiffness dependent manner. The shape of single cells and the composition of tethered matrix protein both influence the magnitude of traction stress applied and the resultant differentiation outcome. We show how geometry guides the spatial positioning of focal adhesions to maximize interaction with the matrix, and uncover a relationship between αvβ3, α5β1 and mechanochemical regulation of osteogenesis. PMID:26285084

  8. Modeling the mechanics of cells in the cell-spreading process driven by traction forces.

    PubMed

    Fang, Yuqiang; Lai, King W C

    2016-04-01

    Mechanical properties of cells and their mechanical interaction with the extracellular environments are main factors influencing cellular function, thus indicating the progression of cells in different disease states. By considering the mechanical interactions between cell adhesion molecules and the extracellular environment, we developed a cell mechanical model that can characterize the mechanical changes in cells during cell spreading. A cell model was established that consisted of various main subcellular components, including cortical cytoskeleton, nuclear envelope, actin filaments, intermediate filaments, and microtubules. We demonstrated the structural changes in subcellular components and the changes in spreading areas during cell spreading driven by traction forces. The simulation of nanoindentation tests was conducted by integrating the indenting force to the cell model. The force-indentation curve of the cells at different spreading states was simulated, and the results showed that cell stiffness increased with increasing traction forces, which were consistent with the experimental results. The proposed cell mechanical model provides a strategy to investigate the mechanical interactions of cells with the extracellular environments through the adhesion molecules and to reveal the cell mechanical properties at the subcellular level as cells shift from the suspended state to the adherent state. PMID:27176326

  9. Surface traction and the dynamics of elastic rods at low Reynolds number.

    PubMed

    Strawbridge, Eva M; Wolgemuth, Charles W

    2012-09-01

    Molecular and cell biological processes often use proteins and structures that are significantly longer in one dimension than they are in the other two, for example, DNA, actin, and bacterial flagella. The dynamics of these structures are the consequence of the balance between the elastic forces from the structure itself and viscous forces from the surrounding fluid. Typically, the motion of these filamentary objects is described using variations of the Kirchhoff rod equations with resistive forces from the fluid treated as body forces acting on the centerline. In reality, though, these forces are applied to the surface of the filament; however, the standard derivation of the Kirchhoff equations ignores surface traction stresses. Here, we rederive the Kirchhoff rod equations in the presence of resistive traction stresses and determine the conditions under which treating the drag forces as body forces is reasonable. We show that in most biologically relevant cases the standard implementation of resistive forces into the Kirchhoff rod equations is applicable; however, we note one particular biological system where the Kirchhoff rod formalism may not apply.

  10. Surface traction and the dynamics of elastic rods at low Reynolds number

    NASA Astrophysics Data System (ADS)

    Strawbridge, Eva M.; Wolgemuth, Charles W.

    2012-09-01

    Molecular and cell biological processes often use proteins and structures that are significantly longer in one dimension than they are in the other two, for example, DNA, actin, and bacterial flagella. The dynamics of these structures are the consequence of the balance between the elastic forces from the structure itself and viscous forces from the surrounding fluid. Typically, the motion of these filamentary objects is described using variations of the Kirchhoff rod equations with resistive forces from the fluid treated as body forces acting on the centerline. In reality, though, these forces are applied to the surface of the filament; however, the standard derivation of the Kirchhoff equations ignores surface traction stresses. Here, we rederive the Kirchhoff rod equations in the presence of resistive traction stresses and determine the conditions under which treating the drag forces as body forces is reasonable. We show that in most biologically relevant cases the standard implementation of resistive forces into the Kirchhoff rod equations is applicable; however, we note one particular biological system where the Kirchhoff rod formalism may not apply.

  11. Traction-assisted colonic endoscopic submucosal dissection using clip and line: a feasibility study

    PubMed Central

    Yamasaki, Yasushi; Takeuchi, Yoji; Uedo, Noriya; Kato, Minoru; Hamada, Kenta; Aoi, Kenji; Tonai, Yusuke; Matsuura, Noriko; Kanesaka, Takashi; Yamashina, Takeshi; Akasaka, Tomofumi; Hanaoka, Noboru; Higashino, Koji; Ishihara, Ryu; Iishi, Hiroyasu

    2016-01-01

    Background and study aims: Colonic endoscopic submucosal dissection (ESD) is a challenging procedure because it is often difficult to maintain good visualization of the submucosal layer. To facilitate colonic ESD, we designed a novel traction method, namely traction-assisted colonic ESD using clip and line (TAC), and investigated its feasibility. Patients and methods: We retrospectively analyzed 23 patients with large colonic superficial lesions who had undergone TAC. The main outcome was the procedural success rate of TAC, which we defined as successful, sustained application of clip and line to the lesion until the end of the procedure. Results: The procedural success rate of TAC was 87 % (20/23). In all three unsuccessful cases, the lesions were in the proximal colon and the procedure times over 100 minutes. The overall mean procedure time was 61 min (95 % confidence interval, 18 – 172 min). We achieved en bloc resections of all lesions. There were no perforations or fatal adverse events. Conclusions: TAC is feasible and safe for colonic ESD and may improve the ease of performing this procedure. PMID:26793785

  12. Integrin-Matrix Clusters Form Podosome-like Adhesions in the Absence of Traction Forces

    PubMed Central

    Yu, Cheng-han; Rafiq, Nisha Bte Mohd; Krishnasamy, Anitha; Hartman, Kevin L.; Jones, Gareth E.; Bershadsky, Alexander D.; Sheetz, Michael P.

    2013-01-01

    Summary Matrix-activated integrins can form different adhesion structures. We report that nontransformed fibroblasts develop podosome-like adhesions when spread on fluid Arg-Gly-Asp peptide (RGD)-lipid surfaces, whereas they habitually form focal adhesions on rigid RGD glass surfaces. Similar to classic macrophage podosomes, the podosome-like adhesions are protrusive and characterized by doughnut-shaped RGD rings that surround characteristic core components including F-actin, N-WASP, and Arp2/Arp3. Furthermore, there are 18 podosome markers in these adhesions, though they lack matrix metalloproteinases that characterize invadopodia and podosomes of Src-transformed cells. When nontransformed cells develop force on integrin-RGD clusters by pulling RGD lipids to prefabricated rigid barriers (metal lines spaced by 1–2 μm), these podosomes fail to form and instead form focal adhesions. The formation of podosomes on fluid surfaces is mediated by local activation of phosphoinositide 3-kinase (PI3K) and the production of phosphatidylinositol-(3,4,5)-triphosphate (PIP3) in a FAK/PYK2-dependent manner. Enrichment of PIP3 precedes N-WASP activation and the recruitment of RhoA-GAP ARAP3. We propose that adhesion structures can be modulated by traction force development and that production of PIP3 stimulates podosome formation and subsequent RhoA downregulation in the absence of traction force. PMID:24290759

  13. Traumatic Pseudoaneurysm of the Superficial Temporal Artery due to Gardner Traction.

    PubMed

    Lee, Hyun Seok; Jo, Kwang Wook; Lee, Sun Ho; Eoh, Whan

    2010-09-01

    We report a case of pseudoaneurysm of the parietal division of the superficial temporal artery (STA) secondary to iatrogenic head injury due to Gardner traction. A 54-year-old man presented with a pulsatile, cystic, and painless mass in the right anterior temporal region which developed three weeks after head fixation via Gardner traction. At the time of discovery, the mass was 10 mm in diameter, compressible and disappeared after manual compression of the proximal STA. A bruit was audible over the mass, which was thought to be a pseudoaneurysm. A computed tomography angiogram (CTA) showed a pseudoaneurysm of the parietal division of the right STA. The tip of the pseudoaneurysm was thrombosed and was both red and tender. The pseudoaneurysm was thought to be filled with infected thrombus, and the mass was resected with ligation of the proximal and distal ends of the STA. A pseudoaneurysm of the STA should be suspected when there is a history of possible vessel injury, such as a history of head-pin fixation, and when a patient presents with a pulsatile, cystic mass near the temple. Pseudoaneurysms can be successfully treated by excision.

  14. Intramedullary nailing of acute femoral shaft fractures using manual traction without a fracture table.

    PubMed

    Karpos, P A; McFerran, M A; Johnson, K D

    1995-02-01

    Intramedullary (IM) nails were prospectively placed in 32 consecutive femoral shaft fractures without the use of a fracture table. All fractures were reduced using manual traction. Pathologic and nonacute fractures and those requiring a reconstruction nail were excluded. The results are compared with results of two prior study groups from this institution that underwent IM nailing with or without a fracture table using a femoral distractor. Ten patients had unstable spine or pelvis fractures. Four nailings followed exploratory laparotomy. Twelve patients underwent two or more procedures on the lower extremities under the same preparation and drape. Six fractures were open. Sixty-seven percent of results were anatomic, 27% had < 5 mm lengthening/shortening or < 5 degree varus/valgus, and 7% had > 5 mm lengthening/shortening or > 5 degree varus/valgus. Average operative time was 95 min. No complications occurred that were attributable to the technique. Compared with the prior study groups, no statistical difference in the fracture types or results was found. However, operative time was significantly less in the manual traction group (p < .05). We feel that this technique is a safe, simple, and effective alternative to using a fracture table. The technique is especially useful in the polytrauma patient, significantly decreasing anesthetic time.

  15. [The results of using extraoral traction in children with a prognathic bite].

    PubMed

    Latiĭ, A A

    1990-01-01

    Primary and repeated lateral teleroentgenograms of the head of 37 children aged 4-8 with prognathic occlusion were analyzed, recorded on an average in 2 years after employment of a chin sling with extraoral traction. Analysis has shown normalization of the jaws and occlusion in the sagittal plane, resultant from limitation of mesial transposition of the mandible in the skull in the course of facial skeleton growth. This has been achieved at the expense of inhibition of longitudinal growth of the mandibular body and ascending branches more than twofold as against the reference values and was also a result of mandibular shift due to traction and of enhanced vertical transposition of the mandible in the skull due to distal rotation. The principal indications for the employment of chin sling in the management of prognathic occlusion are intensive growth of the mandible or a tendency to such growth, mesial position of the mandible in the skull, and a combination of these disorders, that may be the principal or additional factors contributing to the pathogenesis of this abnormality.

  16. Idiopathic vitreomacular traction and macular hole: a comprehensive review of pathophysiology, diagnosis, and treatment

    PubMed Central

    Steel, D H W; Lotery, A J

    2013-01-01

    Posterior vitreous detachment (PVD) is a common phenomenon in the aging eye. However, this may be complicated by persistent symptomatic vitreomacular adhesions that exert tractional forces on the macula (vitreomacular traction; VMT). VMT itself may be associated with epiretinal membrane formation and the development of idiopathic macular holes (IMH). Such pathologies may cause visual disturbances, including metamorphopsia, photopsia, blurred vision, and decreased visual acuity, which impact an individual's quality of life. Technologies such as optical coherence tomography allow an increasingly more accurate visualisation of the macular anatomy, including quantification of macular hole characteristics, and this facilitates treatment decision-making. Pars plana vitrectomy remains the primary treatment option for many patients with VMT or IMH; for the latter, peeling of the inner limiting membrane (ILM) of the retina has shown improved outcomes when compared with no ILM peeling. The development of narrow-gauge transconjunctival vitrectomy systems has improved the rate of visual recovery following surgery. Ocriplasmin, by degrading laminin and fibronectin at the vitreoretinal interface, may allow induction of PVD in a non-invasive manner. Indeed, clinical studies have supported its use as an alternative to surgery in certain patient populations. However, further research is still needed with respect to greater understanding of the pathophysiology underlying the development of VMT and IMH. PMID:24108069

  17. Characterization of Intracellular Streaming and Traction Forces in Migrating Physarum Plasmodia

    NASA Astrophysics Data System (ADS)

    Zhang, Shun; Lewis, Owen; Guy, Robert; Del Alamo, Juan Carlos

    2015-11-01

    Physarum plasmodium is a model organism for cell migration that exhibits fast intracellular streaming. Single amoebae were seeded and allowed to move on polyacrilamide gels that contained 0.5-micron fluorescent beads. Joint time-lapse sequences of intracellular streaming and gel deformation were acquired respectively in the bright and fluorescent fields under microscope. These images were analyzed using particle image velocimetry (PIV) algorithms, and the traction stresses applied by the amoebae on the surface were computed by solving the elastostatic equation for the gel using the measured bead displacements as boundary conditions. These measurements provide, for the first time, a joint characterization of intracellular mass transport, the forces applied on the substrate and the signal of free intracellular calcium with high resolution in both time and space, enables a through study about the locomotive mechanism, shedding light on related biomimetic research. The results reveal a pronounced auto-oscillation character in intracellular flow, contact area, centroid speed and strain energy, all with the same periodicity about 100 seconds. Locomotion modes that were distinct in flow/ traction stress pattern as well as migration speed have been discovered and studied.

  18. Cell traction in collective cell migration and morphogenesis: The chase and run mechanism

    PubMed Central

    Szabó, András; Mayor, Roberto

    2015-01-01

    Directional collective cell migration plays an important role in development, physiology, and disease. An increasing number of studies revealed key aspects of how cells coordinate their movement through distances surpassing several cell diameters. While physical modeling and measurements of forces during collective cell movements helped to reveal key mechanisms, most of these studies focus on tightly connected epithelial cultures. Less is known about collective migration of mesenchymal cells. A typical example of such behavior is the migration of the neural crest cells, which migrate large distances as a group. A recent study revealed that this persistent migration is aided by the interaction between the neural crest and the neighboring placode cells, whereby neural crest chase the placodes via chemotaxis, but upon contact both populations undergo contact inhibition of locomotion and a rapid reorganization of cellular traction. The resulting asymmetric traction field of the placodes forces them to run away from the chasers. We argue that this chase and run interaction may not be specific only to the neural crest system, but could serve as the underlying mechanism for several morphogenetic processes involving collective cell migration. PMID:26267782

  19. Traumatic Pseudoaneurysm of the Superficial Temporal Artery due to Gardner Traction

    PubMed Central

    Lee, Hyun Seok; Lee, Sun Ho; Eoh, Whan

    2010-01-01

    We report a case of pseudoaneurysm of the parietal division of the superficial temporal artery (STA) secondary to iatrogenic head injury due to Gardner traction. A 54-year-old man presented with a pulsatile, cystic, and painless mass in the right anterior temporal region which developed three weeks after head fixation via Gardner traction. At the time of discovery, the mass was 10 mm in diameter, compressible and disappeared after manual compression of the proximal STA. A bruit was audible over the mass, which was thought to be a pseudoaneurysm. A computed tomography angiogram (CTA) showed a pseudoaneurysm of the parietal division of the right STA. The tip of the pseudoaneurysm was thrombosed and was both red and tender. The pseudoaneurysm was thought to be filled with infected thrombus, and the mass was resected with ligation of the proximal and distal ends of the STA. A pseudoaneurysm of the STA should be suspected when there is a history of possible vessel injury, such as a history of head-pin fixation, and when a patient presents with a pulsatile, cystic mass near the temple. Pseudoaneurysms can be successfully treated by excision. PMID:21082063

  20. Methods of the aerodynamical experiments with simulation of massflow-traction ratio of the power unit

    NASA Astrophysics Data System (ADS)

    Lokotko, A. V.

    2016-10-01

    Modeling massflow-traction characteristics of the power unit (PU) may be of interest in the study of aerodynamic characteristics (ADC) aircraft models with full dynamic likeness, and in the study of the effect of interference PU. These studies require the use of a number of processing methods. These include: 1) The method of delivery of the high-pressure body of jets model engines on the sensitive part of the aerodynamic balance. 2) The method of estimate accuracy and reliability of measurement thrust generated by the jet device. 3) The method of implementation of the simulator SU in modeling the external contours of the nacelle, and the conditions at the inlet and outlet. 4) The method of determining the traction simulator PU. 5) The method of determining the interference effect from the work of power unit on the ADC of model. 6) The method of producing hot jets of jet engines. The paper examines implemented in ITAM methodology applied to testing in a supersonic wind tunnel T-313.

  1. The effects of surface traction characteristics on frictional demand and kinematics in tennis.

    PubMed

    Damm, Loïc; Low, Daniel; Richardson, Andrea; Clarke, James; Carré, Matt; Dixon, Sharon

    2013-11-01

    The interaction between footwear and surfaces influences the forces experienced by tennis players. The purpose of this study was to investigate traction demand and kinematic adaptation during tennis-specific movements with changes in traction characteristics of surfaces. We hypothesised that players would increase the utilised coefficient of friction (horizontal to vertical ground reaction force ratio) when the shoe surface combination had a high coefficient of friction and flex their knee after contact to facilitate braking. Eight participants performed two separate movements, side jump out of stance and running forehand. Ground reaction force was measured and three-dimensional kinematic data were recorded. Clay surface and cushioned acrylic hard court (low vs. high shoe-surface friction) were used. The peak utilised coefficient of friction was greater on clay than the hard court. The knee was less flexed at impact on clay (-5.6 +/- 10.2 degrees) and at peak flexion (-13.1 +/- 12.0 degrees) during the running forehand. Our results indicate that tennis players adapt the level ofutilised friction according to the characteristics of the surface, and this adaptation favours sliding on the low friction surface. Less knee flexion facilitates sliding on clay, whereas greater knee flexion contributes to braking on the hard court.

  2. Lateral traction

    MedlinePlus

    Browner BD, Jupiter JP, Krettek C, Anderson PA. Closed fracture management. In: Browner BD, Jupiter JP, Krettek C, Anderson PA, eds. Skeletal Trauma: Basic Science, Management, and Reconstruction . 5th ...

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

    PubMed Central

    Yang, Hae-sun; Yoo, Won-gyu

    2014-01-01

    [Purpose] This study investigated the effect of stretching with lumbar traction on VAS and Oswestry scale scores of lumbar 4–5 herniated intervertebral disc (HIVD) patients. [Subjects] We recruited 20 lumbar 4–5 HIVD patients. [Methods] We performed stretching with lumbar traction for lumbar 4–5 HIVD patients during 4 weeks. The VAS and Oswestry scales were measured before and 4 weeks after the intervention. [Results] The results showed a significant decrease in VAS scale scores for stretching with lumbar traction in lumbar 4–5 HIVD patients, from 18±1.29 to 2.1±1.35. The Oswestry scale scores also decreased significantly, from 20.35±2.01 to 3.5±2.84, after stretching with lumbar traction. [Conclusion] Thus, we suggest stretching with lumbar traction for lumbar 4–5 HIVD patients. PMID:25140094

  4. Nesting in perception of affordances for stepping and leaping.

    PubMed

    Wagman, Jeffrey B; Bai, Jiuyang; Smith, Peter J K

    2016-08-01

    Perception of affordances for a given behavior typically reflects the task-specific action capabilities of the perceiver. However, many experiments have shown a discrepancy between the perceptual and behavioral boundaries for a given behavior. One possibility for such a discrepancy is that the context of many experimental tasks transformed what is typically a dynamic perception-action task into an analytical or reflective judgment. We investigated this hypothesis with respect to perception of maximum stepping and leaping distance. For both behaviors, perception of these affordances more closely reflected action capabilities when the perceptual task was nested within a superordinate task than when it was not (regardless of whether the behavior itself was performed). Additionally, verbal reports of perception of maximum leaping distance more closely reflected action capabilities when there was an explicit time limit on such reports. The results are discussed in the context of the ecological principle of nesting and in attentional focus during motor control tasks. PMID:27220935

  5. Small businesses and the Affordable Care Act of 2010.

    PubMed

    Collins, Sara R; Davis, Karen; Nicholson, Jennifer L; Stremikis, Kristof

    2010-09-01

    The Patient Protection and Affordable Care Act (ACA) includes several short- and long-term provisions designed to help small businesses pay for and maintain health insurance for their workers, and to allow workers without employer coverage to gain access to affordable, comprehensive health insurance. Provisions include a small business tax credit to offset premium costs for firms that offer coverage starting this taxable year, establishment of state-based insurance exchanges that promise to lower administrative costs and pool risk more broadly, and creation of new market rules and an essential benefit standard to protect small firms and their workers. Analysis shows that up to 16.6 million workers are in firms that would be eligible for the tax credit in 2010 to 2013. Over the next 10 years, small businesses and organizations could receive an estimated $40 billion in federal support through the premium credit program. PMID:20812427

  6. Motivational Affordance and Risk-Taking Across Decision Domains.

    PubMed

    Zou, Xi; Scholer, Abigail A

    2016-03-01

    We propose a motivational affordance account to explain both stability and variability in risk-taking propensity in major decision domains. We draw on regulatory focus theory to differentiate two types of motivation (prevention, promotion) that play a key role in predicting risk-taking. Study 1 demonstrated that prevention motivation is negatively associated with risk-taking across six key decision domains, including health/safety, ethics, recreation, gambling, investment, and social. In contrast, promotion motivation is positively associated with risk-taking in the social and investment domains. Study 2 replicated the same pattern and provided direct evidence that promotion motivation is a strong predictor of risk-taking only in domains where there is true potential for gains. Study 3 manipulated promotion (vs. prevention) motivation experimentally to demonstrate that motivational affordance is a critical mechanism for understanding risk-taking behaviors. PMID:26802189

  7. The Affordable Care Act: Opportunities and Challenges for Physicians.

    PubMed

    Chen, Min

    2015-11-01

    The Affordable Care Act (ACA) will affect many aspects of health care across the nation, presenting both opportunities and challenges. Physicians who have a solid understanding of the recent industry trends and the role they will be playing in the post-ACA world will be able to better adapt to the new environment. This article analyzes the implications of the health care reform for physicians and offers recommendations on how to turn challenges into opportunities. PMID:26501969

  8. Options for Affordable Planetary Fission Surface Power Systems

    NASA Technical Reports Server (NTRS)

    Houts, Mike; Gaddis, Steve; Porter, Ron; VanDyke, Melissa; Martin, Jim; Godfroy, Tom; Bragg-Sitton, Shannon; Garber, Anne; Pearson, Boise

    2006-01-01

    Nuclear fission systems could serve as "workhorse" power plants for the Vision for Space Exploration. In this context, the "workhorse" power plant is defined as a system that could provide power anywhere on the surface of the moon or Mars, land on the moon using a Robotic Lunar Exploration Program (RLEP)-developed lander, and would be a viable, affordable option once power requirements exceed that which can be provided by existing energy systems.

  9. Promoting Prevention Through the Affordable Care Act: Workplace Wellness

    PubMed Central

    Roffenbender, Jason S.; Goetzel, Ron Z.; Millard, Francois; Wildenhaus, Kevin; DeSantis, Charles; Novelli, William

    2012-01-01

    Public health in the United States can be improved by building workplace “cultures of health” that support healthy lifestyles. The Affordable Care Act (ACA), which includes the Prevention and Public Health Fund, will support a new focus on prevention and wellness, offering opportunities to strengthen the public’s health through workplace wellness initiatives. This article describes the opportunity the ACA provides to improve worker wellness. PMID:23237245

  10. Monolithic QCL design approaches for improved reliability and affordability

    NASA Astrophysics Data System (ADS)

    Law, K. K.

    2013-12-01

    Many advances have been made recently in mid-wave infrared and long-wave infrared quantum cascade lasers (QCLs) technologies, and there is an increasing demand for these laser sources for ever expanding Naval, DoD and homeland security applications. We will discuss in this paper a portfolio of various Naval Air Warfare Weapons Division's current and future small business innovative research programs and efforts on significantly improving QCLs' performance, affordability, and reliability.

  11. The Affordable Care Act: Opportunities and Challenges for Physicians.

    PubMed

    Chen, Min

    2015-11-01

    The Affordable Care Act (ACA) will affect many aspects of health care across the nation, presenting both opportunities and challenges. Physicians who have a solid understanding of the recent industry trends and the role they will be playing in the post-ACA world will be able to better adapt to the new environment. This article analyzes the implications of the health care reform for physicians and offers recommendations on how to turn challenges into opportunities.

  12. Radiation Shielding Options for the Affordable Fission Surface Power System

    SciTech Connect

    Craft, Aaron E.; King, Jeffrey C.

    2009-03-16

    The Affordable Fission Surface Power System (AFSPS) is a proposed power source for an outpost capable of housing six humans for up to six weeks on the lunar surface and emphasizes the design principles of low risk and affordability over high performance. The radiation shield is the most massive component of the reactor system and its effect on launch mass greatly affects the affordability of the AFSPS. Potential shielding materials include lithium hydride, enriched boron-10 carbide, water, borated water, beryllium, boron-doped beryllium and zirconium hydride. Zirconium hydride is the most effective neutron attenuator and also significantly attenuates gamma radiation, but at a significant mass penalty. The other neutron attenuating materials all require the addition of a tungsten layer to provide significant gamma attenuation. Based on neutron radiation alone, lithium hydride is the lightest of the potential attenuators, followed by water and borated water. When gamma radiation is also considered, the lithium hydride/tungsten shield is shown to be the lightest composite shield with a combined mass of 3246 kg, followed by the borated water/tungsten shield (3479 kg). The boron carbide/tungsten shield has a total mass of 4129 kg, but represents significantly less development risk.

  13. Approach to an Affordable and Productive Space Transportation System

    NASA Technical Reports Server (NTRS)

    McCleskey, Carey M.; Rhodes, Russel E.; Lepsch, Roger A.; Henderson, Edward M.; Robinson, John W.

    2012-01-01

    This paper describes an approach for creating space transportation architectures that are affordable, productive, and sustainable. The architectural scope includes both flight and ground system elements, and focuses on their compatibility to achieve a technical solution that is operationally productive, and also affordable throughout its life cycle. Previous papers by the authors and other members of the Space Propulsion Synergy Team (SPST) focused on space flight system engineering methods, along with operationally efficient propulsion system concepts and technologies. This paper follows up previous work by using a structured process to derive examples of conceptual architectures that integrate a number of advanced concepts and technologies. The examples are not intended to provide a near-term alternative architecture to displace current near-term design and development activity. Rather, the examples demonstrate an approach that promotes early investments in advanced system concept studies and trades (flight and ground), as well as in advanced technologies with the goal of enabling highly affordable, productive flight and ground space transportation systems.

  14. The visual encoding of tool-object affordances.

    PubMed

    Natraj, N; Pella, Y M; Borghi, A M; Wheaton, L A

    2015-12-01

    The perception of tool-object pairs involves understanding their action-relationships (affordances). Here, we sought to evaluate how an observer visually encodes tool-object affordances. Eye-movements were recorded as right-handed participants freely viewed static, right-handed, egocentric tool-object images across three contexts: correct (e.g. hammer-nail), incorrect (e.g. hammer-paper), spatial/ambiguous (e.g. hammer-wood), and three grasp-types: no hand, functional grasp-posture (grasp hammer-handle), non-functional/manipulative grasp-posture (grasp hammer-head). There were three areas of interests (AOI): the object (nail), the operant tool-end (hammer-head), the graspable tool-end (hammer-handle). Participants passively evaluated whether tool-object pairs were functionally correct/incorrect. Clustering of gaze scanpaths and AOI weightings grouped conditions into three distinct grasp-specific clusters, especially across correct and spatial tool-object contexts and to a lesser extent within the incorrect tool-object context. The grasp-specific gaze scanpath clusters were reasonably robust to the temporal order of gaze scanpaths. Gaze was therefore automatically primed to grasp-affordances though the task required evaluating tool-object context. Participants also primarily focused on the object and the operant tool-end and sparsely attended to the graspable tool-end, even in images with functional grasp-postures. In fact, in the absence of a grasp, the object was foveally weighted the most, indicative of a possible object-oriented action priming effect wherein the observer may be evaluating how the tool engages on the object. Unlike the functional grasp-posture, the manipulative grasp-posture caused the greatest disruption in the object-oriented priming effect, ostensibly as it does not afford tool-object action due to its non-functional interaction with the operant tool-end that actually engages with the object (e.g., hammer-head to nail). The enhanced attention

  15. Are Marketplace Plans Affordable? Consumer Perspectives from the Commonwealth Fund Affordable Care Act Tracking Survey, March-May 2015.

    PubMed

    Collins, Sara R; Gunja, Munira; Rasmussen, Petra W; Doty, Michelle M; Beutel, Sophie

    2015-09-01

    Most employers who provide health insurance to employees subsidize their premiums and provide a comprehensive benefit package. Before the Affordable Care Act, people who lacked health insurance through a job and purchased it on their own paid the full cost of their plans, which often came with skimpy benefit packages and high deductibles. Findings from the Commonwealth Fund Affordable Care Act Tracking Survey, March--May 2015, indicate that the law's tax credits have made premium costs in health plans sold through the marketplaces roughly comparable to employer plans, at least for people with low and moderate incomes. At higher incomes, the phase-out of the subsidies means that adults in marketplace plans have higher premium costs than those in employer plans. Overall, larger shares of adults in marketplace plans reported deductibles of $1,000 or more, compared with those in employer plans, though these differences were narrower among low-and moderate-income adults.

  16. Are Marketplace Plans Affordable? Consumer Perspectives from the Commonwealth Fund Affordable Care Act Tracking Survey, March-May 2015.

    PubMed

    Collins, Sara R; Gunja, Munira; Rasmussen, Petra W; Doty, Michelle M; Beutel, Sophie

    2015-09-01

    Most employers who provide health insurance to employees subsidize their premiums and provide a comprehensive benefit package. Before the Affordable Care Act, people who lacked health insurance through a job and purchased it on their own paid the full cost of their plans, which often came with skimpy benefit packages and high deductibles. Findings from the Commonwealth Fund Affordable Care Act Tracking Survey, March--May 2015, indicate that the law's tax credits have made premium costs in health plans sold through the marketplaces roughly comparable to employer plans, at least for people with low and moderate incomes. At higher incomes, the phase-out of the subsidies means that adults in marketplace plans have higher premium costs than those in employer plans. Overall, larger shares of adults in marketplace plans reported deductibles of $1,000 or more, compared with those in employer plans, though these differences were narrower among low-and moderate-income adults. PMID:26445739

  17. Patient Protection and Affordable Care Act; establishment of the multi-state plan program for the Affordable Insurance Exchanges.

    PubMed

    2013-03-11

    The U.S. Office of Personnel Management (OPM) is issuing a final regulation establishing the Multi-State Plan Program (MSPP) pursuant to the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act of 2010, referred to collectively as the Affordable Care Act. Through contracts with OPM, health insurance issuers will offer at least two multi-State plans (MSPs) on each of the Affordable Insurance Exchanges (Exchanges). One of the issuers must be non-profit. Under the law, an MSPP issuer may phase in the States in which it offers coverage over 4 years, but it must offer MSPs on Exchanges in all States and the District of Columbia by the fourth year in which the MSPP issuer participates in the MSPP. This rule aims to balance adhering to the statutory goals of MSPP while aligning its standards to those applying to qualified health plans to promote a level playing field across health plans.

  18. Identifying traction-separation behavior of self-adhesive polymeric films from in situ digital images under T-peeling

    NASA Astrophysics Data System (ADS)

    Nase, Michael; Rennert, Mirko; Naumenko, Konstantin; Eremeyev, Victor A.

    2016-06-01

    In this paper procedures are developed to identify traction-separation curves from digital images of the deformed flexible films during peeling. T-peel tests were performed for self-adhesive polymeric films. High quality photographs of the deformed shape within and outside the zone of adhesive interaction were made in situ by the digital light microscope. The deformed line is approximated by a power series with coefficients computed by minimizing a least squares functional. Two approaches to identify the traction-separation curve for the given deformation line are proposed. The first one is based on the energy integral of the non-linear theory of rods and allows the direct evaluation of the adhesion force potential. The second one utilizes the complementary energy type variational equation and the Ritz method to compute the adhesion force. The accuracy of both approaches is analyzed with respect to different approximations for the deformed line and the force of interaction. The obtained traction vs. axial coordinate and the traction-separation curves provide several properties of the adhesive system including the maximum adhesion force, the length of the adhesive zone and the equilibrium position, where the adhesive force is zero while the separation is positive.

  19. Cellular adhesome screen identifies critical modulators of focal adhesion dynamics, cellular traction forces and cell migration behaviour

    PubMed Central

    Fokkelman, Michiel; Balcıoğlu, Hayri E.; Klip, Janna E.; Yan, Kuan; Verbeek, Fons J.; Danen, Erik H. J.; van de Water, Bob

    2016-01-01

    Cancer cells migrate from the primary tumour into surrounding tissue in order to form metastasis. Cell migration is a highly complex process, which requires continuous remodelling and re-organization of the cytoskeleton and cell-matrix adhesions. Here, we aimed to identify genes controlling aspects of tumour cell migration, including the dynamic organization of cell-matrix adhesions and cellular traction forces. In a siRNA screen targeting most cell adhesion-related genes we identified 200+ genes that regulate size and/or dynamics of cell-matrix adhesions in MCF7 breast cancer cells. In a subsequent secondary screen, the 64 most effective genes were evaluated for growth factor-induced cell migration and validated by tertiary RNAi pool deconvolution experiments. Four validated hits showed significantly enlarged adhesions accompanied by reduced cell migration upon siRNA-mediated knockdown. Furthermore, loss of PPP1R12B, HIPK3 or RAC2 caused cells to exert higher traction forces, as determined by traction force microscopy with elastomeric micropillar post arrays, and led to considerably reduced force turnover. Altogether, we identified genes that co-regulate cell-matrix adhesion dynamics and traction force turnover, thereby modulating overall motility behaviour. PMID:27531518

  20. A Novel Method for Localizing Reporter Fluorescent Beads Near the Cell Culture Surface for Traction Force Microscopy

    PubMed Central

    Knoll, Samantha G.; Ali, M. Yakut; Saif, M. Taher A.

    2014-01-01

    PA gels have long been used as a platform to study cell traction forces due to ease of fabrication and the ability to tune their elastic properties. When the substrate is coated with an extracellular matrix protein, cells adhere to the gel and apply forces, causing the gel to deform. The deformation depends on the cell traction and the elastic properties of the gel. If the deformation field of the surface is known, surface traction can be calculated using elasticity theory. Gel deformation is commonly measured by embedding fluorescent marker beads uniformly into the gel. The probes displace as the gel deforms. The probes near the surface of the gel are tracked. The displacements reported by these probes are considered as surface displacements. Their depths from the surface are ignored. This assumption introduces error in traction force evaluations. For precise measurement of cell forces, it is critical for the location of the beads to be known. We have developed a technique that utilizes simple chemistry to confine fluorescent marker beads, 0.1 and 1 µm in diameter, in PA gels, within 1.6 μm of the surface. We coat a coverslip with poly-D-lysine (PDL) and fluorescent beads. PA gel solution is then sandwiched between the coverslip and an adherent surface. The fluorescent beads transfer to the gel solution during curing. After polymerization, the PA gel contains fluorescent beads on a plane close to the gel surface. PMID:25286326