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, 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  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. 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.

  11. 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.

  12. 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.

  13. 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.

  14. Lead-acid traction batteries for electric road vehicle propulsion Directions for research and development

    NASA Astrophysics Data System (ADS)

    Rand, D. A. J.

    1980-09-01

    Little information exists on the behavior of lead-acid batteries operating under the duty cycles normal to electric road vehicle service. Important battery requirements for the propulsion of traffic-compatible electric vehicles include a deep-discharge capability at high efficiencies of active material utilization, and a long cycle life. In order to optimize power-source characteristics to meet these criteria, especially for passenger cars, it is necessary to gain full knowledge of the influence of actual vehicle service on the performance of traction batteries. This article defines areas in which both fundamental and applied work are required to achieve this aim based on the current performance of the lead-acid system.

  15. 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

  16. 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

  17. 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

  18. 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.

  19. Lateral traction

    MedlinePlus

    ... be used to treat or reduce any joint dislocation or bone fracture by applying tension to the leg or arm with weights and pulleys to realign the bone. For example, it may be used to help keep a dislocated hip within the hip socket while it heals. Traction ...

  20. 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.

  1. 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.

  2. Traction behavior of two traction lubricants

    NASA Technical Reports Server (NTRS)

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

    1983-01-01

    In the analysis of rolling-sliding concentrated contacts, such as gears, bearings and traction drives, the traction characteristics of the lubricant are of prime importance. The elastic shear modulus and limiting shear stress properties of the lubricant dictate the traction/slip characteristics and power loss associated with an EHD contact undergoing slip and/or spin. These properties can be deducted directly from the initial slope m and maximum traction coefficient micron of an experimental traction curve. In this investigation, correlation equations are presented to predict m and micron for two modern traction fluids based on the regression analysis of 334 separate traction disk machine experiments. The effects of contact pressure, temperature, surface velocity, ellipticity ratio are examined. Problems in deducing lubricant shear moduli from disk machine tests are discussed.

  3. 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

  4. 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

  5. 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

  6. 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.

  7. Sizing criterial for traction drives

    NASA Technical Reports Server (NTRS)

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

    1983-01-01

    A simplified traction drive fatigue analysis which was derived from the Lundberg-Palmgren theory is measured and the effects of rotational speed, multiplicity of contacts, and variation in the available traction coefficient on traction drive system life, size, and power capacity was investigated. Simplified equations are provided for determining the 90% survival life rating of steel traction drive contacts of arbitrary geometry. References to life modifying factors for material, lubrication, and traction will be made.

  8. 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.

  9. 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

  10. Open coil traction system.

    PubMed

    Vibhute, Pavankumar Janardan

    2012-01-01

    Sliding mechanics have become a popular method for space closure, with the development of preadjusted edgewise appliances. Furthermore, various space closing auxiliaries have been developed and extensively evaluated for their clinical efficiency. Their effectiveness is enhanced with optimum force magnitude and low load deflection rate/force decay. With the advent of nickel-titanium (Ni-Ti) springs in orthodontics, load deflection rates have been markedly reduced. To use Ni-Ti springs, clinicians have to depend upon prefabricated closed coil springs. The open coil traction system, or open coil retraction spring, is developed utilizing Ni-Ti open coil springs for orthodontic space closure. This article describes the fabrication and clinical application of the open coil traction system, which has a number of advantages. It sustains a low load deflection rate with optimum force magnitude, and its design is adjustable for a desired length and force level. It is fail-safe for both activation and deactivation (ie, it cannot be overactivated, and the decompression limit of the open coil is controlled by the operator). The open coil traction system can be offset from the mucosa to help reduce soft tissue impingement. PMID:22567645

  11. 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.

  12. Traction calculations and design data for two traction fluids

    NASA Technical Reports Server (NTRS)

    Tevaarwerk, J. L.

    1983-01-01

    The rheological properties of the fluid under these certain conditions which precludes the use of most of the conventional instruments for steady state measurement were studied. The only suitable type of instrument is a disk machine where most of the conditions are the same of similar to those in traction drives. From the resulting traction tests, certain models are inferred. To the designer of traction drives, the traction behavior of the fluid under the severe conditions is of utmost importance because of the direct influence that it has on the efficiency, size, and life of a given drive.

  13. 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

  14. 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.

  15. Ac traction gets on track

    SciTech Connect

    O`Connor, L.

    1995-09-01

    This article describes inverter-based ac traction systems which give freight locomotives greater adhesion, pulling power, and braking capacity. In the 1940s, dc traction replaced the steam engine as a source of train propulsion, and it has ruled the freight transportation industry ever since. But now, high-performance ac-traction systems, with their unprecedented levels of pulling power and adhesion, are becoming increasingly common on America`s freight railroads. In thousands of miles of demonstration tests, today`s ac-traction systems have outperformed traditional dc-motor driven systems. Major railroad companies are convinced enough of the benefits of ac traction to have integrated it into their freight locomotives.

  16. Simple cost model for EV traction motors

    NASA Astrophysics Data System (ADS)

    Cuenca, R. M.

    1995-02-01

    A simple cost model has been developed that allows the calculation of the OEM (original equipment manufacturer) 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.

  17. 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.

  18. 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.

  19. 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.

  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. Spin analysis of concentrated traction contacts

    NASA Technical Reports Server (NTRS)

    Loewenthal, S. H.

    1983-01-01

    Spin, the result of a mismatch in contact radii on either side of the point of rolling, has a detrimental effect on traction contact performance. It occurs in concentrated contacts having conical or contoured rolling elements, such as those in traction drives or angular contact bearings, and is responsible for an increase in contact heating and power loss. The kinematics of spin producing contact geometries and the subsequent effect on traction and power loss are investigated. The influence of lubricant traction characteristics and contact geometries that minimize spin are also addressed.

  2. 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....

  3. 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....

  4. 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....

  5. 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....

  6. 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....

  7. 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.

  8. 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...

  9. 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...

  10. Study on the Constants of Permanent Magnet Synchronous Motor for Railway Vehicle Traction.

    NASA Astrophysics Data System (ADS)

    Kondo, Keiichiro; Kondo, Minoru

    We have been investigating to apply permanent magnet synchronous motors (PMSMs) to railway vehicle traction, because the efficiency of PMSMs are higher than that of induction motors and they are expected to enable the traction motor down sized. We have to consider peculiarity on the railway vehicle traction when we design the electrical constants of PMSMs. On this paper, we point out the particular points which we have to take into account on designing works and analyze how the constants of PMSMs affect the their performance. Through this study, we suggest how to design the constants and applied the method to assumed designing works to verify the method. We conclude that the suggested method is available for the designing of PMSMs’ constants and reluctance torque is essential to the performance PMSMs for railway vehicle traction purpose.

  11. Liposome adhesion generates traction stress

    NASA Astrophysics Data System (ADS)

    Murrell, Michael P.; Voituriez, Raphaël; Joanny, Jean-François; Nassoy, Pierre; Sykes, Cécile; Gardel, Margaret L.

    2014-02-01

    Mechanical forces generated by cells modulate global shape changes required for essential life processes, such as polarization, division and spreading. Although the contribution of the cytoskeleton to cellular force generation is widely recognized, the role of the membrane is considered to be restricted to passively transmitting forces. Therefore, the mechanisms by which the membrane can directly contribute to cell tension are overlooked and poorly understood. To address this, we directly measure the stresses generated during liposome adhesion. We find that liposome spreading generates large traction stresses on compliant substrates. These stresses can be understood as the equilibration of internal, hydrostatic pressures generated by the enhanced membrane tension built up during adhesion. These results underscore the role of membranes in the generation of mechanical stresses on cellular length scales and that the modulation of hydrostatic pressure due to membrane tension and adhesion can be channelled to perform mechanical work on the environment.

  12. 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.

  13. An analysis of traction drive torsional stiffness

    NASA Technical Reports Server (NTRS)

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

    1983-01-01

    The tangential compliance of elastic bodies in concentrated contact applied to traction drive elements to determine their torsional stiffness was analyzed. Static loading and rotating conditions are considered. The effects of several design variables are shown. The theoretical torsional stiffness of a fixed ratio multiroller drive is computed and compared to experimental values. It is shown that the torsional compliance of the traction contacts themselves is a relatively small portion of the overall drive system compliance.

  14. 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. PMID:7115034

  15. 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. PMID:26957767

  16. 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.

  17. Advanced endoscopic submucosal dissection with traction.

    PubMed

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

    2014-07-16

    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

  18. Modeling traction forces in collective cell migration

    NASA Astrophysics Data System (ADS)

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

    2015-03-01

    Collective cell migration is an important process in embryonic development, wound healing, and cancer metastasis. We have developed a particle-based simulation for collective cell migration that describes flow patterns and finger formation at the tissue edge observed in wound healing experiments. We can apply methods for calculating intercellular stress to our simulation model, and have thereby provided evidence for the validity of a stress reconstitution method from traction forces used in experiments. To accurately capture experimentally measured traction forces and stresses in the tissue, which are mostly tensile, we have to include intracellular acto-myosin contraction into our simulation. We can then reproduce the experimentally observed behavior of cells moving around a circular obstacle, and suggest underlying mechanisms for cell-cell alignment and generation of traction force patterns.

  19. 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

  20. 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.

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

    PubMed Central

    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. PMID:26957767

  2. 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

  3. 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.

  4. 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

  5. Traction boundary conditions for molecular static simulations

    NASA Astrophysics Data System (ADS)

    Li, Xiantao; Lu, Jianfeng

    2016-08-01

    This paper presents a consistent approach to prescribe traction boundary conditions in atomistic models. Due to the typical multiple-neighbor interactions, finding an appropriate boundary condition that models a desired traction is a non-trivial task. We first present a one-dimensional example, which demonstrates how such boundary conditions can be formulated. We further analyze the stability, and derive its continuum limit. We also show how the boundary conditions can be extended to higher dimensions with an application to a dislocation dipole problem under shear stress.

  6. TRAM HOUSE INTERIOR, LOOKING SOUTHEAST. NOTE TRACTION CABLE BULL WHEEL ...

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

    TRAM HOUSE INTERIOR, LOOKING SOUTHEAST. NOTE TRACTION CABLE BULL WHEEL AND DEPARTING BUCKET "12," STILL ON RAIL AND JUST PRIOR TO ENGAGING TRACTION CABLE. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  7. Achieving health care affordability.

    PubMed

    Payson, Norman C

    2002-10-01

    Not all plans are jumping headlong into the consumer-centric arena. In this article, the CEO of Oxford Health Plans discusses how advanced managed care can achieve what other consumer-centric programs seek to do--provide affordable, quality health care. PMID:12391815

  8. Three single wheel machines for traction and soil compaction research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three single wheel machines for traction and soil compaction research have been developed in recent years at the USDA-ARS National Soil Dynamics Laboratory. The Traction Research Vehicle has been used extensively for soil bin traction and soil compaction experiments. The vehicle uses feedback comp...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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.

  15. 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

  16. 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

  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. Perioperative lower extremity peripheral nerve traction injuries.

    PubMed

    Plastaras, Christopher T; Chhatre, Akhil; Kotcharian, Ashot S

    2014-01-01

    Peripheral nerve traction injuries may occur after surgical care and can involve any of the lower extremity large peripheral nerves. In this review, the authors discuss injuries after knee or hip surgical intervention. The diagnosis, including electrodiagnostic studies, is time sensitive and also relies on a detailed history and physical examination. Successful prevention and treatment involve familiarity with risk and predisposing factors as well as prophylactic measures. PMID:24267207

  19. 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.

  20. Traction forces at solid-lubricated rolling/sliding contacts

    NASA Technical Reports Server (NTRS)

    Aggarwal, B. B.; Bovenkerk, R. L.

    1985-01-01

    A single-element traction rig was used to measure the traction forces at a solid-lubricated contact of a ball against a flat disk at room temperature under combine rolling and sliding. The load and speed conditions were selected to match those anticipated for bearing applications in adiabatic diesel engines. Traction vs slide/roll ratio curves were similar to those for liquid lubricants but the traction forces were an order of magnitude higher. The test data were used to derive equations to predict traction force as a function of contact stress and rolling speed. The data showed that the magnitude of traction forces were almost the same for all the lubricants tested. The lubricants, should, therefore, be selected on the basis of their ability to limit the wear of contact surfaces.

  1. 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.

  2. Investigations of the factors causing performance losses of lead/acid traction batteries

    NASA Astrophysics Data System (ADS)

    Kronberger, H.; Fabjan, Ch.; Gofas, N.

    A failure analysis is carried out with a lead/acid traction battery after a two-years' test run in an electric passenger car. A survey of the operational data, in combination with laboratory tests and chemical and physical analyses, reveals the main causes of battery damage and performance loss: insufficiencies of the charging procedure, inadequate maintainance (water-refilling system), antimony-contamination and loss of the active material due to grid corrosion and shedding of PbO 2.

  3. 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

  4. 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.

  5. 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.

  6. Changes in cervical muscle activity according to the traction force of an air-inflatable neck traction device.

    PubMed

    Kang, Jong Ho; Park, Tae-Sung

    2015-09-01

    [Purpose] The purpose of this study was to analyze cervical muscle activity at different traction forces of an air-inflatable neck traction device. [Subjects] Eighteen males participated in this study. [Methods] The subjects put on an air-inflatable neck traction device and the traction forces administered were 40, 80, and 120 mmHg. The electromyography (EMG) signals of the splenius capitis, and upper trapezius were measured to assess the muscle activity. [Results] The muscle activity of the splenius capitis was significantly higher at 80, and 120 mmHg compared to 40 mmHg. The muscle activity of the upper trapezius did not show significant differences among the traction forces. [Conclusion] Our research result showed that the air-inflatable home neck traction device did not meet the condition of muscle relaxation. PMID:26504278

  7. Changes in cervical muscle activity according to the traction force of an air-inflatable neck traction device

    PubMed Central

    Kang, Jong Ho; Park, Tae-Sung

    2015-01-01

    [Purpose] The purpose of this study was to analyze cervical muscle activity at different traction forces of an air-inflatable neck traction device. [Subjects] Eighteen males participated in this study. [Methods] The subjects put on an air-inflatable neck traction device and the traction forces administered were 40, 80, and 120 mmHg. The electromyography (EMG) signals of the splenius capitis, and upper trapezius were measured to assess the muscle activity. [Results] The muscle activity of the splenius capitis was significantly higher at 80, and 120 mmHg compared to 40 mmHg. The muscle activity of the upper trapezius did not show significant differences among the traction forces. [Conclusion] Our research result showed that the air-inflatable home neck traction device did not meet the condition of muscle relaxation. PMID:26504278

  8. 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.

  9. Super-Resolved Traction Force Microscopy (STFM)

    PubMed Central

    2016-01-01

    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. PMID:26923775

  10. 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. PMID:26923775

  11. Progressive Release of Vitreomacular Traction With Aflibercept.

    PubMed

    Schwartz, Stephen G; Flynn, Harry W

    2016-05-01

    A patient with combined diabetic macular edema (DME) and vitreomacular traction (VMT) was treated with a series of intravitreal aflibercept (Eylea; Regeneron, Tarrytown, NY) injections. The VMT progressively released during the course of the five intravitreal injections. This release may have been spontaneous, due to a nonspecific mechanical effect from the injections, or due to a pharmacologic effect from the aflibercept. While treating DME, anti-vascular endothelial growth factor agents may have an additional benefit in releasing VMT. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:477-481.]. PMID:27183554

  12. 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

  13. 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.

  14. 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

  15. 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

  16. 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.

  17. Advancements in electric and hybrid electric vehicle technology

    SciTech Connect

    1994-12-31

    Contents of this volume include: Influence of Battery Characteristics on Traction Drive Performance; Chassis Design for a Small Electric City Car; Thermal Comfort of Electric Vehicles; Power Quality Problems at Electric Vehicle`s Charging Station; The Development and Performance of the AMPhibian Hybrid Electric Vehicle; The Selection of Lead-Acid Batteries for Use in Hybrid Electric Vehicles; and more.

  18. 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

  19. 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.

  20. 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.

  1. Modular PM Motor Drives for Automotive Traction Applications

    SciTech Connect

    Su, G.J.

    2001-10-29

    This paper presents modular permanent magnet (PM) motor drives for automotive traction applications. A partially modularized drive system consisting of a single PM motor and multiple inverters is described. The motor has multiple three-phase stator winding sets and each winding set is driven with a separate three-phase inverter module. A truly modularized inverter and motor configuration based on an axial-gap PM motor is then introduced, in which identical PM motor modules are mounted on a common shaft and each motor module is powered by a separate inverter module. The advantages of the modular approach for both inverter and motor include: (1) power rating scalability--one design meets different power requirements by simply stacking an adequate number of modules, thus avoiding redesigning and reducing the development cost, (2) increased fault tolerance, and (3) easy repairing. A prototype was constructed by using two inverters and an axial-gap PM motor with two sets of three-phase stat or windings, and it is used to assist the diesel engine in a hybrid electric vehicle converted from a Chevrolet Suburban. The effect of different pulse-width-modulation strategies for both motoring and regenerative modes on current control is analyzed. Torque and regenerative control algorithms are implemented with a digital signal processor. Analytical and initial testing results are included in the paper.

  2. 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.

  3. 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

  4. Traction Stresses Exerted by Adherent Cells: From Angiogenesis to Metastasis

    NASA Astrophysics Data System (ADS)

    Reinhart-King, Cynthia

    2010-03-01

    Cells exert traction stresses against their substrate that mediate their ability to sense the mechanical properties of their microenvironment. These same forces mediate cell adhesion, migration and the formation of stable cell-cell contacts during tissue formation. In this talk, I will present our data on the traction stresses generated by endothelial cells and metastatic breast cancer cells focused on understanding the processes of angiogenesis and metastasis, respectively. In the context of capillary formation, our data indicate that the mechanics of the substrate play a critical role in establishing endothelial cell-cell contacts. On more compliant substrates, endothelial cell shape and traction stresses polarize and promote the formation of stable cell-cell contacts. On stiffer substrates, traction stresses are less polarized and cell connectivity is disrupted. These data indicate that the mechanical properties of the microenvironment may drive cell connectivity and the formation of stable cell-cell contacts through the reorientation of traction stresses. In our studies of metastatic cell migration, we have found that traction stresses increase with increasing metastatic potential. We investigated three lines of varying metastatic potential (MCF10A, MCF7 and MDAMB231). MDAMB231, which are the most invasive, exert the most significant forces as measured by Traction Force Microscopy. These data present the possibility that cellular traction stress generation aids in the ability of metastatic cells to migrate through the matrix-dense tumor microenvironment. Such measurements are integral to link the mechanical and chemical microenvironment with the resulting response of the cell in health and disease.

  5. 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

  6. 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.

  7. 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…

  8. 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

  9. 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.

  10. 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

  11. An international analysis of cigarette affordability

    PubMed Central

    Blecher, E; van Walbeek, C P

    2004-01-01

    Objective: To investigate how affordable cigarettes are in developed and developing countries, and to calculate by how much the affordability of cigarettes has changed between 1990 and 2001; and secondly, to investigate the relation between cigarette affordability and consumption. Design: Affordability was defined as the cost of cigarettes relative to per capita income. Trends in cigarette affordability, and affordability elasticities of demand, were estimated using regression techniques. Subjects: Seventy countries were investigated, of which 28 are categorised as high income developed countries, while 42 are categorised as developing countries. Cigarette prices were obtained for the main city/cities in the countries. Results: Despite the fact that cigarettes are more expensive in developed countries, the high levels of income make cigarettes more affordable in these countries vis-à-vis developing countries. Of the 28 developed countries, cigarettes became more affordable in 11 and less affordable in 17 countries during the 1990s. Of the 42 developing countries, cigarettes became more affordable in 24 and less affordable in 18 countries. Based on a cross sectional analysis, a 1% increase in the relative income price (the inverse of cigarette affordability) is expected to decrease cigarette consumption by between 0.49–0.57%. Conclusions: Cigarette affordability, more than just the price, determines cigarette consumption. While cigarettes have become more affordable in many developing countries, some developing countries (for example, South Africa, Poland, and Thailand) have implemented strong and effective tobacco control policies, and have been able to decrease cigarette consumption as a result. PMID:15564616

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Parallel manipulator robot assisted femoral fracture reduction on traction table.

    PubMed

    Lin, H; Wang, J Q; Han, W

    2013-01-01

    The principle of femoral shaft fracture reduction is to restore its pre-fractured limb length and mechanical axis. The current documented treatment method with traction table reduction does not conform to the quantitative alignment and reduction. There is also a great amount of X-Ray radiation exposure to both surgeon and patient during the procedure. For this reason, we introduced an innovated Parallel Manipulator Robot (PMR) application: A Femoral Shaft Fracture Reduction with Parallel Manipulator Robot on Traction Table. With this application, the quantitative control on fracture reduction and alignment can be achieved and the radiation exposure to both surgeons and patients can be greatly reduced. PMID:24110820

  17. 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.

  18. Railgun power supply system utilizing traction motors and vacuum interrupters

    SciTech Connect

    Parsons, W.M.; Parker, J.V.; Thullen, P.

    1985-01-01

    A railgun power supply has been designed that utilizes traction motors, vacuum interrupters and pulse transformers. An assembly of 28 traction motors, which store approximately 75 MJ, energize the primary windings of three pulse transformers at a peak current of 50 kA. At peak current an array of vacuum interrupters disconnects the transformer primary windings and forces the current to flow in the secondary windings. The secondary windings are connected directly to the railgun and require no opening switches. By staging the vacuum interrupter openings, a 1 MA to 1.3 MA ramped current waveform can be delivered to the railgun.

  19. 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 ...

  20. 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...

  1. 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

  2. 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…

  3. Single Cell Traction Microscopy within 3D Collagen Matrices

    NASA Astrophysics Data System (ADS)

    Wu, Mingming

    2014-03-01

    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, our current understanding of cell-ECM and cell-cell mechanical interactions is largely derived from 2D traction force microscopy, in which cells are cultured on a flat substrate. It is now clear that what we learn about cellular behavior on a 2D substrate does not always apply to cells embedded within a 3D biomatrix. 3D traction microscopy is emerging for mapping traction fields of single cells embedded in 3D gel, but current methods cannot account for the fibrous and nonlinear properties of collagen gel. In this talk, I will present a forward computation algorithm that we have developed for 3D cell traction measurements within collagen gels. The application of this technology to understanding cancer migration and invasion will be discussed. This work is supported by the National Center for Research Resources (5R21RR025801-03, NIH) and the National Institute of General Medical Sciences (8 R21 GM103388-03,NIH), and the Cornell Center on the Microenvironment & Metastasis.

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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…

  9. 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...

  10. Apicotomy as treatment for failure of orthodontic traction.

    PubMed

    Osório, Leandro Berni; Ferrazzo, Vilmar Antonio; Serpa, Geraldo; Ferrazzo, Kívia Linhares

    2013-01-01

    Objective. The purpose of this study was to present a case report that demonstrated primary failure in a tooth traction that was subsequently treated with apicotomy technique. Case Report. A 10-year-old girl had an impacted upper right canine with increased pericoronal space, which was apparent on a radiographic image. The right maxillary sinus showed an opacity suggesting sinusitis. The presumptive diagnosis was dentigerous cyst associated with maxillary sinus infection. The plan for treatment included treatment of the sinus infection and cystic lesion and orthodontic traction of the canine after surgical exposure and bonding of an orthodontic appliance. The surgical procedure, canine position, root dilaceration, and probably apical ankylosis acted in the primary failure of the orthodontic traction. Surgical apical cut of the displaced teeth was performed, and tooth position in the dental arch was possible, with a positive response to the pulp vitality test. Conclusion. Apicotomy is an effective technique to treat severe canine displacement and primary orthodontic traction failure of palatally displaced canines. PMID:24383010

  11. 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.

  12. 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

  13. 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).

  14. High Resolution, Large Deformation 3D Traction Force Microscopy

    PubMed Central

    López-Fagundo, Cristina; Reichner, Jonathan; Hoffman-Kim, Diane; Franck, Christian

    2014-01-01

    Traction Force Microscopy (TFM) is a powerful approach for quantifying cell-material interactions that over the last two decades has contributed significantly to our understanding of cellular mechanosensing and mechanotransduction. In addition, recent advances in three-dimensional (3D) imaging and traction force analysis (3D TFM) have highlighted the significance of the third dimension in influencing various cellular processes. Yet irrespective of dimensionality, almost all TFM approaches have relied on a linear elastic theory framework to calculate cell surface tractions. Here we present a new high resolution 3D TFM algorithm which utilizes a large deformation formulation to quantify cellular displacement fields with unprecedented resolution. The results feature some of the first experimental evidence that cells are indeed capable of exerting large material deformations, which require the formulation of a new theoretical TFM framework to accurately calculate the traction forces. Based on our previous 3D TFM technique, we reformulate our approach to accurately account for large material deformation and quantitatively contrast and compare both linear and large deformation frameworks as a function of the applied cell deformation. Particular attention is paid in estimating the accuracy penalty associated with utilizing a traditional linear elastic approach in the presence of large deformation gradients. PMID:24740435

  15. Recurrent carpal tunnel syndrome, epineural fibrous fixation, and traction neuropathy.

    PubMed

    Hunter, J M

    1991-08-01

    This article has reviewed recurrent carpal tunnel syndrome, epineural fibrous fixation, and traction neuropathy of the median nerve. The problems surrounding the diagnosis and treatment of recurrent CTS have been discussed at length. The percent of failures from traditional open ligament surgery is observed to be high, and will become more prevalent as more casual treatments are carried out. This article makes a positive statement with reference to mobilization of the median nerve and anatomic restoration of the transverse carpal ligament. Fibrous fixation of the median nerve is a product of life and function. All cases are different, reflecting the strength, abilities, and personalities of the patients. A bottom line is drawn on these patients, where the summation of the problems of life become symptomatic and disabling. Epineural fibrous fixations induce median nerve traction, governed by hand, wrist, and forearm movements. Traction and tension suggest the intermittent disturbance of nerve nutrition and nerve conduction as the elastic limits of the nerve are approached. These factors accumulate and, in time, cause traction neuropathies with pain. This is followed by a reduced work capability. This impairment can be reversed by surgical nerve mobilization followed by functional nerve gliding therapy. A background history injury to the hand and wrist may be significant, as well as factors such as overuse and misuse of the hand and extremity. Prior to surgery, the careful application of diagnostic stress tests are essential, for the differential diagnosis of fixation traction and positional peripheral neuropathies. Nerve mobilization supported by magnification and the techniques of hand surgery has been successful by the methods discussed and has permitted, importantly, the restoration of the anatomic retinaculum for the flexor tendon system. This can be restored in carpal tunnel surgery and reconstructed with basic ligament material in recurrent carpal tunnel

  16. Energy efficient affordable housing. Final report

    SciTech Connect

    1995-07-01

    In 1994, the Southface Energy Institute, working with support from US DOE, initiated a program to provide technical assistance to nonprofit organizations developing affordable housing in the Olympic target communities of Atlanta. The specific project goals were: Identify the barriers that nonprofit affordable housing providers face in increasing the energy and resource efficiency of affordable housing; Assist them in developing the resources to overcome these barriers; Develop specific technical materials and program models that will enable these affordable housing groups to continue to improve the energy efficiency of their programs; and, To transfer the program materials to other affordable housing providers. This report summarizes the progress made in each of these areas.

  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. 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

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Surface Transportation Board Iowa Traction Railway Company--Acquisition and Operation Exemption--Rail Line... pleadings, referring to Docket No. FD 35670, must be filed with the Surface Transportation Board, 395...

  19. 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.

  20. 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

  1. 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.

  2. Fabrication of Superconducting Traction Transformer for Railway Rolling Stock

    NASA Astrophysics Data System (ADS)

    Kamijo, H.; Hata, H.; Fujimoto, H.; Inoue, A.; Nagashima, K.; Ikeda, K.; Yamada, H.; Sanuki, Y.; Tomioka, A.; Uwamori, K.; Yoshida, S.; Iwakuma, M.; Funaki, K.

    2006-06-01

    We designed a floor type single-phase 4 MVA superconducting traction transformer for Shinkansen rolling stock. In this study, we fabricated a prototype superconducting traction transformer based on this design. This transformer of the core-type design has a primary winding, four secondary windings and a tertiary winding. The windings are wound by Bi2223 superconducting tapes and cooled by subcooled liquid nitrogen. The core is kept at room temperature. The cryostat is made of GFRP with two holes to pass core legs through. The outer dimensions are about 1.2m × 0.7m × 1.9m excluding the compressor. Its weight is 1.71t excluding that of refrigerator and compressor. The transformer was tested according to Japanese Industrial Standards (JIS)-E5007. We confirmed that the performance of transformer has been achieved almost exactly as planned. The rated capacity is equivalent to 3.5MVA in the superconducting state.

  3. 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

  4. 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

  5. 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.

  6. 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.

  7. 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

  8. 24 CFR 572.120 - Affordability standards.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 3 2014-04-01 2013-04-01 true Affordability standards. 572.120...) Homeownership Program Requirements-Implementation Grants § 572.120 Affordability standards. (a) Initial... annual incomes of eligible families using reasonable standards and procedures consistently applied.)...

  9. 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…

  10. 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…

  11. Section 8: Affordable Housing for Exceptional Families

    ERIC Educational Resources Information Center

    Wright, Wesley E.

    2009-01-01

    Shelter is a basic human need. Unfortunately, affordable housing is a need that low income families who are caring for children and adults with disabilities can rarely afford without assistance. Because participating families generally pay rent of no more than 30 percent of their adjusted monthly income, the Section 8 program can provide…

  12. 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.

  13. 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

  14. 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

  15. 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.

  16. Analysis of DNA equilibrium configuration under interfacial traction.

    PubMed

    Wang, Y Z; Zhang, Q C; Wang, W; Yang, Y W

    2016-01-01

    Kirchhoff thin elastic rod models are important in the study of the mechanism determining the configurations of flexible structures not only at the macroscopic but also at the microscopic scale. In this study, the energy balance method has been well applied to analyze the configuration of a DNA elastic rod in the presence of interfacial traction. An approximate solution for the shape equations has been obtained, and the relationship between the interfacial factor and the configuration of the DNA segment is derived. The results may provide an explanation for the onset of the formation of kinks in DNA when immersed in a solution. PMID:27323042

  17. 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.

  18. 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

  19. 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 ...

  20. Body-scaled affordances in sensory substitution.

    PubMed

    Travieso, David; Gómez-Jordana, Luis; Díaz, Alex; Lobo, Lorena; Jacobs, David M

    2015-12-15

    The research field on sensory substitution devices has strong implications for theoretical work on perceptual consciousness. One of these implications concerns the extent to which the devices allow distal attribution. The present study applies a classic empirical approach on the perception of affordances to the field of sensory substitution. The reported experiment considers the perception of the stair-climbing affordance. Participants judged the climbability of steps apprehended through a vibrotactile sensory substitution device. If measured with standard metric units, climbability judgments of tall and short participants differed, but if measured in units of leg length, judgments did not differ. These results are similar to paradigmatic results in regular visual perception. We conclude that our sensory substitution device allows the perception of affordances. More generally, we argue that the theory of affordances may enrich theoretical debates concerning sensory substitution to a larger extent than has hitherto been the case. PMID:26587958

  1. 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.

  2. 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

  3. 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.

  4. Modulation of visual attention by object affordance.

    PubMed

    Garrido-Vásquez, Patricia; Schubö, Anna

    2014-01-01

    Some objects in our environment are strongly tied to motor actions, a phenomenon called object affordance. A cup, for example, affords us to reach out to it and grasp it by its handle. Studies indicate that merely viewing an affording object triggers motor activations in the brain. The present study investigated whether object affordance would also result in an attention bias, that is, whether observers would rather attend to graspable objects within reach compared to non-graspable but reachable objects or to graspable objects out of reach. To this end, we conducted a combined reaction time and motion tracking study with a table in a virtual three-dimensional space. Two objects were positioned on the table, one near, the other one far from the observer. In each trial, two graspable objects, two non-graspable objects, or a combination of both was presented. Participants were instructed to detect a probe appearing on one of the objects as quickly as possible. Detection times served as indirect measure of attention allocation. The motor association with the graspable object was additionally enhanced by having participants grasp a real object in some of the trials. We hypothesized that visual attention would be preferentially allocated to the near graspable object, which should be reflected in reduced reaction times in this condition. Our results confirm this assumption: probe detection was fastest at the graspable object at the near position compared to the far position or to a non-graspable object. A follow-up experiment revealed that in addition to object affordance per se, immediate graspability of an affording object may also influence this near-space advantage. Our results suggest that visuospatial attention is preferentially allocated to affording objects which are immediately graspable, and thus establish a strong link between an object' s motor affordance and visual attention. PMID:24567725

  5. 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 HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.5850 Nonpowered orthopedic traction apparatus and...

  6. Two distinct actin networks mediate traction oscillations to confer mechanosensitivity of focal adhesions

    NASA Astrophysics Data System (ADS)

    Wu, Zhanghan; Plotnikov, Sergey; Waterman, Clare; Liu, Jian

    Cells sense the mechanical stiffness of their extracellular matrix (ECM) by exerting traction force through focal adhesions (FAs), which are integrin-based protein assemblies. Strikingly, FA-mediated traction forces oscillate in time and space and govern durotaxis - the tendency of most cell types to migrate toward stiffer ECM. The underlying mechanism of this intriguing oscillation of FA traction force is unknown. Combing theory and experiment, we develop a model of FA growth, which integrates coordinated contributions of a branched actin network and stress fibers in the process. We show that retrograde flux of branched actin network contributes to a traction peak near the FA distal tip and that stress fiber-mediated actomyosin Contractility generates a second traction peak near the FA center. Formin-mediated stress fiber elongation negatively feeds back with actomyosin Contractility, resulting in the central traction peak oscillation. This underpins observed spatio-temporal patterns of the FA traction, and broadens the ECM stiffness range, over which FAs could accurately adapt with traction force generation. Our findings shed light on the fundamental mechanism of FA mechanosensing and hence durotaxis.

  7. 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…

  8. 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

  9. A modified method of traction for young children with congenital dislocation of the hip as a preliminary to reduction.

    PubMed

    Pan, K L; Rasit, H

    2004-12-01

    Many authors agree that preliminary traction prior to closed or open reduction for congenital dislocation of the hip is helpful. Different ways of traction have been used and each of them has its own advantages and disadvantages. One of the problems in the very young child is the difficulty in maintaining a suitable traction that is biomechanically effective. We found that using a rocker bed made the traction more "user friendly" for the child, the parent and the doctors. PMID:15941161

  10. 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

  11. 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.

  12. 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

  13. Scaling of Traction Stresses with Size of Cohesive Cell Colonies

    NASA Astrophysics Data System (ADS)

    Mertz, Aaron F.; Banerjee, Shiladitya; Che, Yonglu; Marchetti, M. Christina; Horsley, Valerie; Dufresne, Eric R.

    2012-02-01

    We explore the mechanical properties of colonies of cohesive cells adherent on soft substrates. Specifically, we image the spatial distribution of traction stresses exerted by colonies of primary mouse keratinocytes on fibronectin-coated silicone gels. These cells have strong cell-cell adhesions mediated by E-cadherin. We observe that the work performed by a colony on its substrate is concentrated at the colony's periphery. The total work is strongly correlated to the geometrical size of the colony but not to number of cells. In other words, the mechanical output of a large single cell mimics that of a cohesive colony with the same overall size. We compare our findings to a recent theoretical model that treats the cohesive colony as an active gel.

  14. Penile traction therapy for Peyronie's disease-what's the evidence?

    PubMed

    Usta, Mustafa Faruk; Ipekci, Tumay

    2016-06-01

    Penile traction therapy (PTT) is a new therapeutic option for men with Peyronie's disease (PD). However, it has a long history of use in other fields of medicine including bone, skin, skeletal muscle, and Dupuytren's. Mechanotransduction, or gradual expansion of tissue by traction, leads to the formation of new collagen tissue by cellular proliferation. As a molecular result, continuous extension of the fibrous plaque causes significant increases in collagenase and metalloproteinases, and, ultimately, to fibrous plaque softening and extension. This hypothetical knowledge has been supported by recent well designed experimental studies. Furthermore, several clinical papers have provided promising results on the use of PTT in PD patients. It has been shown in some series that the use of PTT significantly increases flaccid and stretched penile lengths and results in significant penile curvature improvement when compared to baseline. Furthermore, the use of PTT concomitantly with either verapamil or interferon α-2b has also been shown to be an effective therapy. Additionally, the beneficial effect of PTT on penile length before or after penile surgery in men with corporal fibrosis has been described. Finally, as a minimally invasive alternative treatment option to penile augmentation surgery in men with dysmorphophobia, PTT use has shown promising results by several experts. Studies have shown that PTT provides an acceptable, minimally invasive method that can produce effective and durable lengthening of the penis in men complaining of a small/short penis. There are, however, several criticisms related to the designs of the reported studies, such as small sample size and selection bias. Well-designed studies with larger numbers of patients and longer follow-up periods are, however, needed to establish the true benefits of PTT. PMID:27298777

  15. 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.

  16. Affordances and the musically extended mind.

    PubMed

    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

  17. 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.

  18. 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…

  19. 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.

  20. Analysis of electromyographic activities of the lumbar erector spinae caused by inversion traction

    PubMed Central

    Kim, Chung Yoo; Kang, Jong Ho

    2016-01-01

    [Purpose] The purpose of this study was to analyze changes in the electromyographic activities of the lumbar erector spinae caused by inversion traction in order to verify the relaxation effect. [Subjects and Methods] The subjects included 60 healthy male adults who were equally and randomly assigned to a 30–30° group, a 30–60° group, and a 60–60° group. Inversion traction was performed for six minutes, and the electromyographic activities of the lumbar erector spinae (L2, L4) were measured before and after inversion traction. [Results] The root mean square values at the L2 and L4 levels on both sides were statistically significantly higher after inversion traction compared with before inversion traction. Before inversion traction, the root mean square values at the L2 and L4 levels on both sides in the 30–60° group and 60–60° group were significantly higher than those in the 30–30° group, while the root mean square values at the L2 and L4 levels on both sides showed no significant differences between the groups before inversion traction. [Conclusion] The findings of this study indicated that IT is more likely to elicits an increase in muscle tension and prevent relaxation of the lumbar erector spinae. PMID:27190459

  1. The Affordable Care Act and orthopaedic trauma.

    PubMed

    Issar, Neil M; Jahangir, A Alex

    2014-10-01

    The Affordable Care Act has resulted in a dramatic governmental restructuring of the healthcare insurance market and delivery system. Orthopaedic traumatologists must be aware of the law's impact on their clinical practice, finances, and overall business model. This includes the effect of accountable care organizations, the Independent Payment Advisory Board, and the Physician Value-Based Payment Modifier program, as well as the impact of the Affordable Care Act's grace period provision, medical device excise tax, and cuts to funding for the Disproportionate Share Hospital program. PMID:25229683

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. The results of preoperative halo-gravity traction in children with severe spinal deformity.

    PubMed

    Garabekyan, Tigran; Hosseinzadeh, Pooya; Iwinski, Henry J; Muchow, Ryan D; Talwalkar, Vishwas R; Walker, Janet; Milbrandt, Todd A

    2014-01-01

    Halo-gravity traction has been used preoperatively for patients with severe spinal deformity but there are limited data in the literature on the results and complications. We studied the outcomes of perioperative halo-gravity traction in children with severe spinal deformity. A retrospective study was carried out on patients who were treated at our center. Twenty-one patients were included in the study. Radiographic and pulmonary function parameters showed significant improvement during the course of traction and at the final follow-up. The overall complication rate was 19%, including two patients with pin loosening and two patients with superficial pin-site infections treated with oral antibiotics. PMID:23942045

  7. Gelled-electrolyte lead/acid batteries for stationary and traction applications

    NASA Astrophysics Data System (ADS)

    May, G. J.; Lenain, P.

    The development of new ranges of valve-regulated lead/acid (VRLA) batteries for stationary and traction applications is described. These batteries are gas recombining and use gelled electrolyte, tubular positive plates cast in lead-calcium-tin alloys and a specially-designed pressure relief valve. For stationary service, comparisons are made with VRLA batteries using absorptive glass mat separators. For traction applications, the relative merits of gel technology against alternative approaches to the achievement of lower maintenance for traction batteries are discussed. Operational experience with these batteries is outlined and guidelines indicated for correct application.

  8. 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…

  9. 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…

  10. 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.

  11. 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.

  12. 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…

  13. 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…

  14. 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

  15. 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…

  16. 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.

  17. 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.

  18. 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.

  19. The Effects of Shoe Traction and Obstacle Height on Lower Extremity Coordination Dynamics during Walking

    PubMed Central

    Decker, Leslie; Houser, Jeremy J.; Noble, John M.; Karst, Gregory M.; Stergiou, Nicholas

    2009-01-01

    This study aims to investigate the effects of shoe traction and obstacle height on lower extremity relative phase dynamics (analysis of intralimb coordination) during walking to better understand the mechanisms employed to avoid slippage following obstacle clearance. Ten participants walked at a self-selected pace during eight conditions: four obstacle heights (0%, 10%, 20%, and 40% of limb length) while wearing two pairs of shoes (low and high traction). A coordination analysis was used and phasing relationships between lower extremity segments were examined. The results demonstrated that significant behavioral changes were elicited under varied obstacle heights and frictional conditions. Both decreasing shoe traction and increasing obstacle height resulted in a more in-phase relationship between the interacting lower limb segments. The higher the obstacle and the lower the shoe traction, the more unstable the system became. These changes in phasing relationship and variability are indicators of alterations in coordinative behavior, which if pushed further may have lead to falling. PMID:19187929

  20. Cyclic traction machine for long-term culture of fibroblast-populated collagen gels.

    PubMed

    Langelier, E; Rancourt, D; Bouchard, S; Lord, C; Stevens, P P; Germain, L; Auger, F A

    1999-01-01

    Our research group has been investigating the effect of cyclic deformations on the evolution of fibroblast populated collagen gels (FPCG). Since existing traction machines are not designed for such an application, we had to design a cyclic traction machine adapted to tissue culture inside an incubator over an extended period of time. Biocompatible materials were used for fabrication to allow for easy sterilization and to prevent any adverse reaction from the tissue. The traction machine is based on a computer-controlled stepping motor system for easy adjustment of the deformation amplitude and frequency. The maximum stretching speed achieved is around 1 mm/s. The traction machine can measure FPCG mechanical properties and perform rupture tests to determine its ultimate strength. Several FPCGs have been successfully cultured with the machine for up to four weeks without any adverse reaction. PMID:9916762

  1. 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.

  2. Both contractile axial and lateral traction force dynamics drive amoeboid cell motility

    PubMed Central

    Bastounis, Effie; Meili, Ruedi; Álvarez-González, Begoña; Francois, Joshua; del Álamo, Juan C.; Lasheras, Juan C.

    2014-01-01

    Chemotaxing Dictyostelium discoideum cells adapt their morphology and migration speed in response to intrinsic and extrinsic cues. Using Fourier traction force microscopy, we measured the spatiotemporal evolution of shape and traction stresses and constructed traction tension kymographs to analyze cell motility as a function of the dynamics of the cell’s mechanically active traction adhesions. We show that wild-type cells migrate in a step-wise fashion, mainly forming stationary traction adhesions along their anterior–posterior axes and exerting strong contractile axial forces. We demonstrate that lateral forces are also important for motility, especially for migration on highly adhesive substrates. Analysis of two mutant strains lacking distinct actin cross-linkers (mhcA− and abp120− cells) on normal and highly adhesive substrates supports a key role for lateral contractions in amoeboid cell motility, whereas the differences in their traction adhesion dynamics suggest that these two strains use distinct mechanisms to achieve migration. Finally, we provide evidence that the above patterns of migration may be conserved in mammalian amoeboid cells. PMID:24637328

  3. 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

  4. Shape and Area of Keratocytes Are Related to the Distribution and Magnitude of Their Traction Forces.

    PubMed

    Sonoda, Ayane; Okimura, Chika; Iwadate, Yoshiaki

    2016-03-26

    Fish epidermal keratocytes maintain an overall fan shape during their crawling migration. The shape-determination mechanism has been described theoretically and experimentally on the basis of graded radial extension of the leading edge, but the relationship between shape and traction forces has not been clarified. Migrating keratocytes can be divided into fragments by treatment with the protein kinase inhibitor staurosporine. Fragments containing a nucleus and cytoplasm behave as mini-keratocytes and maintain the same fan shape as the original cells. We measured the shape of the leading edge, together with the areas of the ventral region and traction forces, of keratocytes and mini-keratocytes. The shapes of keratocytes and mini-keratocytes were similar. Mini-keratocytes exerted traction forces at the rear left and right ends, just like keratocytes. The magnitude of the traction forces was proportional to the area of the keratocytes and mini-keratocytes. The myosin II ATPase inhibitor blebbistatin decreased the forces at the rear left and right ends of the keratocytes and expanded their shape laterally. These results suggest that keratocyte shape depends on the distribution of the traction forces, and that the magnitude of the traction forces depends on the area of the cells. PMID:26754329

  5. 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

  6. Progressive correction of severe spinal deformities with halo-gravity traction.

    PubMed

    Bouchoucha, Sami; Khelifi, Anis; Saied, Walid; Ammar, Chokri; Nessib, Mohamed Nebil; Ben Ghachem, Maher

    2011-08-01

    Treatment of rigid and severe spinal deformities is challenging and risky. Preoperative halo-gravity traction can be used to progressively reduce the deformity before spinal fusion. The aim of this study was to evaluate the effectiveness of halo-gravity traction for the correction of severe spinal deformities. Fifteen patients were reviewed retrospectively. Their mean age at the beginning of traction was 13.5 years. The mean duration of traction was 64 days. The main curve in the coronal plane improved from +/- 95 degrees to +/- 67 degrees, a gain of +/- 28 degrees (range 0 degrees-50 degrees) or +/- 30%. The curve in the sagittal plane improved from +/- 96 degrees to +/- 78 degrees, a gain of +/- 18 degrees (range 0 degrees-45 degrees) or +/- 19%. Other authors report gains up to 46% and 43%, respectively in the coronal and in the sagittal plane, but this might be due to different conditions, techniques, and evaluations. One patient with a pre-existing neurological deficit developed paraplegia. According to the literature congenital curves with associated kyphosis are exposed to paraplegia. Halo-gravity traction is effective and is usually tolerated better than other techniques of traction using the halo device. PMID:21954764

  7. Halogravity traction in the preoperative treatment of scoliosis in twins with Marfan syndrome.

    PubMed

    Cimic, Mislav; Crnogaca, Kresimir; Vrdoljak, Ozren; Bicanic, Goran

    2015-01-01

    We report on the influence of the duration of halogravity traction for achieving curve correction in monozygotic twins with Marfan syndrome who underwent posterior spinal fusion. Review of the medical charts and standard radiograph analysis of twin girls treated at our department was performed. Halogravity traction with a four-pin skull construct was applied for 3 weeks in twin A and for 2 weeks in twin B with a maximum of 20% body weight used. Both were on a 24-hours-day halogravity traction regime. Achieved thoracic curve correction after halogravity traction was 31% in twin A and 18% in twin B. Although less curve correction after traction was achieved in twin B, this had no significant implications on final postoperative curve correction. Halogravity traction can be a useful tool in the preoperative treatment of scoliosis in patients with Marfan syndrome if applied for 3 weeks. In order to avoid complications, we propose that lower weights be used with a starting weight of 1.5 kg increased by 1 kg daily until 20% body weight is reached. PMID:26032703

  8. Algorithm for calculating torque base in vehicle traction control system

    NASA Astrophysics Data System (ADS)

    Li, Hongzhi; Li, Liang; Song, Jian; Wu, Kaihui; Qiao, Yanjuan; Liu, Xingchun; Xia, Yongguang

    2012-11-01

    Existing research on the traction control system(TCS) mainly focuses on control methods, such as the PID control, fuzzy logic control, etc, aiming at achieving an ideal slip rate of the drive wheel over long control periods. The initial output of the TCS (referred to as the torque base in this paper), which has a great impact on the driving performance of the vehicle in early cycles, remains to be investigated. In order to improve the control performance of the TCS in the first several cycles, an algorithm is proposed to determine the torque base. First, torque bases are calculated by two different methods, one based on states judgment and the other based on the vehicle dynamics. The confidence level of the torque base calculated based on the vehicle dynamics is also obtained. The final torque base is then determined based on the two torque bases and the confidence level. Hardware-in-the-loop(HIL) simulation and vehicle tests emulating sudden start on low friction roads have been conducted to verify the proposed algorithm. The control performance of a PID-controlled TCS with and without the proposed torque base algorithm is compared, showing that the proposed algorithm improves the performance of the TCS over the first several cycles and enhances about 5% vehicle speed by contrast. The proposed research provides a more proper initial value for TCS control, and improves the performance of the first several control cycles of the TCS.

  9. Model for how retrograde actin flow regulates adhesion traction stresses.

    PubMed

    Li, Ying; Bhimalapuram, Prabhakar; Dinner, Aaron R

    2010-05-19

    Cells from animals adhere to and exert mechanical forces on their surroundings. Cells must control these forces for many biological processes, and dysfunction can lead to pathologies. How the actions of molecules within a cell are coordinated to regulate the adhesive interaction with the extracellular matrix remains poorly understood. It has been observed that cytoplasmic proteins that link integrin cell-surface receptors with the actin cytoskeleton flow with varying rates from the leading edge toward the center of a cell. Here, we explore theoretically how measurable subcellular traction stresses depend on the local speed of retrograde actin flow. In the model, forces result from the stretching of molecular complexes in response to the drag from the flow; because these complexes break with extension-dependent kinetics, the flow results in a decrease in their number when sufficiently large. Competition between these two effects naturally gives rise to a clutch-like behavior and a nonmonotonic trend in the measured stresses, consistent with recent data for epithelial cells. We use this basic framework to evaluate slip and catch bond mechanisms for integrins; better fits of experimental data are obtained with a catch bond representation. Extension of the model to one comprising multiple molecular interfaces shifts the peak stress to higher speeds. Connections to other models and cell movement are discussed. PMID:21386439

  10. Whiplash-associated chronic headache treated with home cervical traction.

    PubMed

    Olson, V L

    1997-04-01

    The subject of this case report was a 56-year-old woman who sustained a whiplash-associated disorder as a result of a motor vehicle accident. Within a few hours after the accident, she developed a headache, which became chronic, creating disability and hindering the quality of her life. In the following year, a variety of diagnostic tests, medications, and physical therapy were unsuccessful in determining the cause of her complaints or in relieving them. After this year, she expressed anger, frustration, and a reluctance to undergo additional physical therapy. By listening to her explain how she coped with her problem and observing that she lacked the ability to reduce her cervical lordosis, the therapist developed and implemented a home program of supine cervical traction and exercise. After 30 days of treatment, she was able to reduce and control her headache. This treatment and the approach used to develop the treatment may benefit other patients who have whiplash-associated chronic headache. PMID:9105344

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. An affordable open-source turbidimeter.

    PubMed

    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

  17. 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.

  18. Local leadership and the Affordable Care Act.

    PubMed

    Williams, Stephen L; Nichols, Beverly L; Barton, M Katherine; De LaCruz, Maria; Hernandez, Benjamin

    2015-01-01

    Local health departments are in key positions to lead in the education and implementation efforts to advance the Patient Protection and Affordable Care Act. The first enrollment period is over, but the efforts to enroll the uninsured and advocate for expansion of Medicaid in the states that have not yet taken on this expansion will continue for years to come. Political climates may be unsupportive, but some actions may still be possible. PMID:25423062

  19. 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:

  20. 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. PMID:25121814

  1. 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:

  2. 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

  3. Affordable housing through energy efficiency: The Northgate story

    SciTech Connect

    Diamond, R.C.; McAllister, J.A.; Feustel, H.E.; Patullo, C.; Buckley, T.

    1992-03-01

    In this paper we evaluate a comprehensive retrofit and rehabilitation effort to improve the comfort, affordability, and energy efficiency of 336 low-income housing units. The units had complete shell retrofits, including new siding, air-infiltration barriers, new windows and doors, and both roof and foundation insulation. In addition, the existing electric-baseboard heating system was replaced with a new gas-fired boiler for each apartment. New programmable thermostats, refrigerators, and tenant education were also included in the retrofit package. The evaluation of the project included pre- and post-retrofit utility bill analysis, computer simulation to evaluate the cost and saving of the individual measures, and a comprehensive survey of the residents regarding their comfort, behavior, and satisfaction with the retrofits. The analysis has shown energy savings of more than 20% for the shell measures, with a reduction in utility bills of nearly 50% from the combined measures. The resident survey shows high tenant satisfaction with the retrofits.

  4. 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 Enrollment Opportunity...

  5. Hybrid electric vehicle power management system

    DOEpatents

    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.

  6. Price, availability and affordability of medicines

    PubMed Central

    Mhlanga, Brenda S.

    2014-01-01

    Abstract Background Medicines play an important role in healthcare, but prices can be a barrier to patient care. Few studies have looked at the prices of essential medicines in low- and middle-income countries in terms of patient affordability. Aim To determine the prices, availability and affordability of medicines along the supply chain in Swaziland. Setting Private- and public-sector facilities in Manzini, Swaziland. Methods The standardised methodology designed by the World Health Organization and Health Action International was used to survey 16 chronic disease medicines. Data were collected in one administrative area in 10 private retail pharmacies and 10 public health facilities. Originator brand (OB) and lowest-priced generic equivalent (LPG) medicines were monitored and these prices were then compared with international reference prices (IRPs). Affordability was calculated in terms of the daily wage of the lowest-paid unskilled government worker. Results Mean availability was 68% in the public sector. Private sector OB medicines were priced 32.4 times higher than IRPs, whilst LPGs were 7.32 times higher. OBs cost 473% more than LPGs. The total cumulative mark-ups for individual medicines range from 190.99% – 440.27%. The largest contributor to add-on cost was the retail mark-up (31% – 53%). Standard treatment with originator brands cost more than a day's wage. Conclusion Various policy measures such as introducing price capping at all levels of the medicine supply chain, may increase the availability, whilst at the same time reducing the prices of essential medicines for the low income population. PMID:26245401

  7. 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

  8. Situated language understanding as filtering perceived affordances.

    PubMed

    Gorniak, Peter; Roy, Deb

    2007-03-01

    We introduce a computational theory of situated language understanding in which the meaning of words and utterances depends on the physical environment and the goals and plans of communication partners. According to the theory, concepts that ground linguistic meaning are neither internal nor external to language users, but instead span the objective-subjective boundary. To model the possible interactions between subject and object, the theory relies on the notion of perceived affordances: structured units of interaction that can be used for prediction at multiple levels of abstraction. Language understanding is treated as a process of filtering perceived affordances. The theory accounts for many aspects of the situated nature of human language use and provides a unified solution to a number of demands on any theory of language understanding including conceptual combination, prototypicality effects, and the generative nature of lexical items. To support the theory, we describe an implemented system that understands verbal commands situated in a virtual gaming environment. The implementation uses probabilistic hierarchical plan recognition to generate perceived affordances. The system has been evaluated on its ability to correctly interpret free-form spontaneous verbal commands recorded from unrehearsed game play between human players. The system is able to "step into the shoes" of human players and correctly respond to a broad range of verbal commands in which linguistic meaning depends on social and physical context. We quantitatively compare the system's predictions in response to direct player commands with the actions taken by human players and show generalization to unseen data across a range of situations and verbal constructions. PMID:21635295

  9. 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

  10. Dignity for all: affordable assisted living.

    PubMed

    Janeski, James F; Pruchnicki, Alec

    2006-01-01

    In 2026, the first of the baby boomers, including Presidents Clinton and Bush, will reach the age of 80, the average age of residents currently in assisted living facilities. In her book The Denial of Aging: Perpetual Youth, Eternal Life, and Other Dangerous Fantasies, Muriel Gillick proposes that the baby boomers will seek assisted living as an alternative to nursing home care. But what about that portion of the population not able to afford the high cost of private assisted living? What option will be available to the low-asset/low-income population in lieu of nursing home care? PMID:17214248

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. 12 CFR 1291.12 - Affordable Housing Reserve Fund.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 7 2011-01-01 2011-01-01 false Affordable Housing Reserve Fund. 1291.12 Section 1291.12 Banks and Banking FEDERAL HOUSING FINANCE AGENCY HOUSING GOALS AND MISSION FEDERAL HOME LOAN BANKS' AFFORDABLE HOUSING PROGRAM § 1291.12 Affordable Housing Reserve Fund. (a) Deposits. If...

  20. 12 CFR 1291.12 - Affordable Housing Reserve Fund.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 9 2013-01-01 2013-01-01 false Affordable Housing Reserve Fund. 1291.12 Section 1291.12 Banks and Banking FEDERAL HOUSING FINANCE AGENCY HOUSING GOALS AND MISSION FEDERAL HOME LOAN BANKS' AFFORDABLE HOUSING PROGRAM § 1291.12 Affordable Housing Reserve Fund. (a) Deposits. If...

  1. 12 CFR 1291.12 - Affordable Housing Reserve Fund.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 10 2014-01-01 2014-01-01 false Affordable Housing Reserve Fund. 1291.12 Section 1291.12 Banks and Banking FEDERAL HOUSING FINANCE AGENCY HOUSING GOALS AND MISSION FEDERAL HOME LOAN BANKS' AFFORDABLE HOUSING PROGRAM § 1291.12 Affordable Housing Reserve Fund. (a) Deposits. If...

  2. 12 CFR 1291.12 - Affordable Housing Reserve Fund.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 9 2012-01-01 2012-01-01 false Affordable Housing Reserve Fund. 1291.12 Section 1291.12 Banks and Banking FEDERAL HOUSING FINANCE AGENCY HOUSING GOALS AND MISSION FEDERAL HOME LOAN BANKS' AFFORDABLE HOUSING PROGRAM § 1291.12 Affordable Housing Reserve Fund. (a) Deposits. If...

  3. 12 CFR 1291.12 - Affordable Housing Reserve Fund.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Affordable Housing Reserve Fund. 1291.12 Section 1291.12 Banks and Banking FEDERAL HOUSING FINANCE AGENCY HOUSING GOALS AND MISSION FEDERAL HOME LOAN BANKS' AFFORDABLE HOUSING PROGRAM § 1291.12 Affordable Housing Reserve Fund. (a) Deposits. If...

  4. 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

  5. Traction forces mediated by integrin signaling are necessary for definitive endoderm specification.

    PubMed

    Taylor-Weiner, Hermes; Ravi, Neeraja; Engler, Adam J

    2015-05-15

    Pluripotent embryonic stem cells (ESCs) exert low-traction forces on their niche in vitro whereas specification to definitive endoderm in vivo coincides with force-mediated motility, suggesting a differentiation-mediated switch. However, the onset of contractility and extent to which force-mediated integrin signaling regulates fate choices is not understood. To address the requirement of tractions forces for differentiation, we examined mouse embryonic stem cell (ESC) specification towards definitive endoderm on fibrillar fibronectin containing a deformation-sensitive FRET probe. Inhibiting contractility resulted in an increase in the observed fibronectin FRET intensity ratio but also decreased the amount of phosphorylated nuclear SMAD2, leading to reduced expression of the definitive endoderm marker SOX17. By contrast ESCs maintained in pluripotency medium did not exert significant tractions against the fibronectin matrix. When laminin-111 was added to fibrillar matrices to improve the efficiency of definitive endoderm induction, ESCs decreased their fibronectin traction forces in a laminin-dependent manner; blocking the laminin-binding α3-integrin restored fibronectin matrix deformation and reduced SOX17 expression and SMAD2 phosphorylation, probably because of compensation of inhibitory signaling from SMAD7 after 5 days in culture. These data imply that traction forces and integrin signaling are important regulators of early fate decisions in ESCs. PMID:25908864

  6. 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

  7. The Regulation of Traction Force in Relation to Cell Shape and Focal Adhesions

    PubMed Central

    Rape, Andrew; Guo, Wei-hui; Wang, Yu-li

    2011-01-01

    Mechanical forces provide critical inputs for proper cellular functions. The interplay between the generation of, and response to, mechanical forces regulate such cellular processes as differentiation, proliferation, and migration. We postulate that adherent cells respond to a number of physical and topographical factors, including cell size and shape, by detecting the magnitude and/or distribution of traction forces under different conditions. To address this possibility we introduce a new simple method for precise micropatterning of hydrogels, and then apply the technique to systematically investigate the relationship between cell geometry, focal adhesions, and traction forces in cells with a series of spread areas and aspect ratios. Contrary to previous findings, we find that traction force is not determined primarily by the cell spreading area but by the distance from cell center to the perimeter. This distance in turn controls traction forces by regulating the size of focal adhesions, such that constraining the size of focal adhesions by micropatterning can override the effect of geometry. We propose that the responses of traction forces to center-periphery distance, possibly through a positive feedback mechanism that regulates focal adhesions, provide the cell with the information on its own shape and size. A similar positive feedback control may allow cells to respond to a variety of physical or topographical signals via a unified mechanism. PMID:21163521

  8. 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.

  9. Immunologic protection afforded by sunscreens in vitro.

    PubMed

    Davenport, V; Morris, J F; Chu, A C

    1997-06-01

    Several studies have suggested a lack of correlation between sunscreen sun protection factor and protection of the skin immune system, potentially allowing greater damage to the skin by removing the natural protective erythemal response to sun exposure. Despite this, routine testing of immune protection afforded by sunscreens is not performed by industry. Current laboratory methods for investigating the efficacy of sunscreen protection of epidermal immune function use the induction of contact hypersensitivity or epidermal cell alloantigen presentation. Animal models, cell culture systems, and in vivo human studies are commonly employed, but all these systems have significant drawbacks for use in routine testing. The purpose of this study was to develop an in vitro system for testing the immunologic protection afforded by sunscreens in human skin. Five test sunscreens plus a vehicle control were tested in a "blind" fashion for their in vitro level of immune protection. Creams were applied in a standard manner to human whole skin explants and were irradiated over a range of physiologic doses using an Oriel solar simulator. A mixed epidermal lymphocyte reaction was used to quantify epidermal alloantigen-presenting capacity, in the presence or absence of test cream, for five explants. Results consistently demonstrated that all the test sunscreens protected beyond their designated sun protection factors, whereas the vehicle conferred no protection. The explant-mixed epidermal lymphocyte reaction system gave consistent, reproducible results and may prove useful for the allocation of an immune protection factor to all sunscreens. PMID:9182811

  10. Affordable access to care for the undocumented.

    PubMed

    Rosen, Dennis

    2014-09-01

    How do you tell a sick kid that nobody cares if he gets better? That's an exaggeration, of course, but it is the fundamental message our society sends when we tell him that, because he and his family are undocumented immigrants, we are unwilling to extend them access to affordable and reliable health insurance. One major shortcoming of the Affordable Care Act is its specific exclusion of the almost twelve million undocumented immigrants-including millions of children-in this country from access to the state and federal insurance exchanges where coverage can be purchased. It is true that providing undocumented immigrants access to the exchanges and subsidies mandated by the ACA would require additional funding. However, a recent analysis in California has found that the costs of expanding state-supported care to include undocumented immigrants would largely be offset by the increased state sales tax revenue paid by managed care organizations and by reduced spending at the county level on emergency-room and hospital care of the uninsured. PMID:25231664

  11. Modulating DNA configuration by interfacial traction: an elastic rod model to characterize DNA folding and unfolding.

    PubMed

    Huang, Zaixing

    2011-01-01

    As a continuum model of DNA, a thin elastic rod subjected to interfacial interactions is used to investigate the equilibrium configuration of DNA in intracellular solution. The interfacial traction between the rod and the solution environment is derived in detail. Kirchhoff's theory of elastic rods is used to analyze the equilibrium configuration of a DNA segment under the action of the interfacial traction. The influences of the interfacial energy factor and bending stiffness on the toroidal spool formation of the DNA segment are discussed. The results show that the equilibrium configuration of DNA is mainly determined by competition between the interfacial energy and elastic strain energy of the DNA itself, and the interfacial traction is one of the forces that drives DNA folding and unfolding. PMID:22210963

  12. A Five-Leg Inverter for Driving a Traction Motor and a Compressor Motor

    SciTech Connect

    Su, Gui-Jia; Hsu, John S

    2006-01-01

    This paper presents an integrated inverter for speed control of a traction motor and a compressor motor to reduce the compressor drive cost in EV/HEV applications. The inverter comprises five phase-legs; three of which are for control of a three-phase traction motor and the remaining two for a two-phase compressor motor with three terminals. The common terminal of the two-phase motor is tied to the neutral point of the three-phase traction motor to eliminate the requirement of a third phase leg. Further cost savings are made possible by sharing the switching devices, dc bus filter capacitors, gate drive power supplies, and control circuit. Simulation and experimental results are included to verify that speed control of the two motors is independent from each other.

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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…

  20. 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

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. Simulation of Trolleybus Traction Induction Drive With Supercapacitor Energy Storage System

    NASA Astrophysics Data System (ADS)

    Brazis, V.; Latkovskis, L.; Grigans, L.

    2010-01-01

    The article considers the possibilities of saving the regenerative braking energy in Škoda 24Tr type trolleybuses by installing the onboard supercapacitor energy storage system (ESS) and improving its performance with automated switching to the autonomous traction mode. Proposed is an ESS control system with constant DC bus voltage in the supercapacitor charging mode and supercapacitor current proportional to the AC drive current in the discharging mode. The authors investigate stability of the trolleybus ESS control system operating together with AC traction drive in various overhead voltage failure modes. The co-simulation of ESS operation was done by Matlab/Simulink AC drive and PSIM ESS continuous models.

  6. 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.

  7. Determination of lubricant selection based on elastohydrodynamic film thickness and traction measurement

    NASA Technical Reports Server (NTRS)

    Dow, T. A.; Kannel, J. W.

    1979-01-01

    The project was conducted to aid in the development of an elastohydrodynamic specification for military lubricants. Experiments were conducted with a rolling disk apparatus designed to simulate a bearing or gear type contact. Measurements included lubricant film thickness, lubricant breakdown and traction for a range of loads, speeds, temperatures, and surface roughnesses. Several lubricants were used in the investigations including a traction fluid, two synthetic paraffinic lubricants and several lubricants conforming to MIL-L 7808 and 23699 specifications. Recommendations regarding an EHD specification are included.

  8. 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.

  9. 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

  10. 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

  11. 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. PMID:26458377

  12. Traction Stresses and Translational Distortion of the Nucleus During Fibroblast Migration on a Physiologically Relevant ECM Mimic

    PubMed Central

    Pan, Zhi; Ghosh, Kaustabh; Liu, Yajie; Clark, Richard A.F.; Rafailovich, Miriam H.

    2009-01-01

    Cellular traction forces, resulting in cell-substrate physical interactions, are generated by actin-myosin complexes and transmitted to the extracellular matrix through focal adhesions. These processes are highly dynamic under physiological conditions and modulate cell migration. To better understand the precise dynamics of cell migration, we measured the spatiotemporal redistribution of cellular traction stresses (force per area) during fibroblast migration at a submicron level and correlated it with nuclear translocation, an indicator of cell migration, on a physiologically relevant extracellular matrix mimic. We found that nuclear translocation occurred in pulses whose magnitude was larger on the low ligand density surfaces than on the high ligand density surfaces. Large nuclear translocations only occurred on low ligand density surfaces when the rear traction stresses completely relocated to a posterior nuclear location, whereas such relocation took much longer time on high ligand density surfaces, probably due to the greater magnitude of traction stresses. Nuclear distortion was also observed as the traction stresses redistributed. Our results suggest that the reinforcement of the traction stresses around the nucleus as well as the relaxation of nuclear deformation are critical steps during fibroblast migration, serving as a speed regulator, which must be considered in any dynamic molecular reconstruction model of tissue cell migration. A traction gradient foreshortening model was proposed to explain how the relocation of rear traction stresses leads to pulsed fibroblast migration. PMID:19450499

  13. 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

  14. 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.

  15. 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

  16. 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.

  17. Dynamic peripheral traction forces balance stable neurite tension in regenerating Aplysia bag cell neurons

    PubMed Central

    Hyland, Callen; Mertz, Aaron F.; Forscher, Paul; Dufresne, Eric

    2014-01-01

    Growth cones of elongating neurites exert force against the external environment, but little is known about the role of force in outgrowth or its relationship to the mechanical organization of neurons. We used traction force microscopy to examine patterns of force in growth cones of regenerating Aplysia bag cell neurons. We find that traction is highest in the peripheral actin-rich domain and internal stress reaches a plateau near the transition between peripheral and central microtubule-rich domains. Integrating stress over the area of the growth cone reveals that total scalar force increases with area but net tension on the neurite does not. Tensions fall within a limited range while a substantial fraction of the total force can be balanced locally within the growth cone. Although traction continuously redistributes during extension and retraction of the peripheral domain, tension is stable over time, suggesting that tension is a tightly regulated property of the neurite independent of growth cone dynamics. We observe that redistribution of traction in the peripheral domain can reorient the end of the neurite shaft. This suggests a role for off-axis force in growth cone turning and neuronal guidance. PMID:24825441

  18. Dynamic peripheral traction forces balance stable neurite tension in regenerating Aplysia bag cell neurons.

    PubMed

    Hyland, Callen; Mertz, Aaron F; Forscher, Paul; Dufresne, Eric

    2014-01-01

    Growth cones of elongating neurites exert force against the external environment, but little is known about the role of force in outgrowth or its relationship to the mechanical organization of neurons. We used traction force microscopy to examine patterns of force in growth cones of regenerating Aplysia bag cell neurons. We find that traction is highest in the peripheral actin-rich domain and internal stress reaches a plateau near the transition between peripheral and central microtubule-rich domains. Integrating stress over the area of the growth cone reveals that total scalar force increases with area but net tension on the neurite does not. Tensions fall within a limited range while a substantial fraction of the total force can be balanced locally within the growth cone. Although traction continuously redistributes during extension and retraction of the peripheral domain, tension is stable over time, suggesting that tension is a tightly regulated property of the neurite independent of growth cone dynamics. We observe that redistribution of traction in the peripheral domain can reorient the end of the neurite shaft. This suggests a role for off-axis force in growth cone turning and neuronal guidance. PMID:24825441

  19. 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.

  20. [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

  1. 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,…

  2. 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.

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

    SciTech Connect

    Olszewski, M.

    2006-10-31

    , subsystems, and 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 the development of 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 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, 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

  4. 'Traction ribs' on the palaeo-ice stream tracks of the Interior Plains, North America

    NASA Astrophysics Data System (ADS)

    Margold, Martin; Stokes, Chris R.

    2015-04-01

    Spatially distinct pattern of basal shear stress beneath a number of Antarctic and Greenlandic ice streams has recently been discovered by inverse methods using high resolution data of ice velocity, elevation and thickness. Surrounded by regions of near-zero basal shear stress, these areas of high basal shear stress have been termed 'traction ribs' and hold important implications for the force balance of ice streams. The cause of the traction ribs is unknown (i.e. whether they have a topographic expression), but their horizontal dimensions and pattern lie somewhere between typical ribbed (Rogen) moraines and recently described mega-scale ribbed moraines identified on palaeo-ice sheet beds. However, whilst both of these landform types form with their long axis transverse to the ice flow direction, the traction ribs are most commonly oriented oblique to the ice flow at angles of 30-60 degrees. Here, we report new findings from the beds of palaeo-ice streams on the Interior Plains in Alberta and Saskatchewan where landform assemblages, similar to traction ribs, occur at several sites. Individual landforms at the mapped sites have typical lengths (transverse to flow) of 5-10 km, width of ~2 km, and their spacing is ~2-3 km. As such, they appear to represent an intermediate scale of ribbed landform that overlaps with the more extreme (larger) values of classic ribbed moraine and the smaller values of mega-ribs. Unlike mega-ribs and ribbed moraines, we also note that many of the ribbed features we mapped are aligned obliquely to ice flow direction at angles and mimic the arcuate patterns of traction ribs seen under modern ice streams. Profiles across the ridges indicate that they have amplitudes of 10-15 m which is comparable, but slightly lower than the mean value for ribbed moraines. The resemblance of our newly mapped features to the traction ribs of modern ice streams is close not only in the size and shape but also in the overall pattern of the whole landform

  5. 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)......

  6. 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.

  7. 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

  8. 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.

  9. Control your mind, make affordance available.

    PubMed

    Jin, Zheng; Lee, Yang; Zhu, Jin

    2015-01-01

    Evaluating the affordance-control interpretation of the relationship between performance and object estimation has been proposed by psychophysical and psychonomic studies. This study examined the weight estimation-performance relationship. Individuals with visual impairment or blindness put shots that varied in weight among five scales. In Experiment 1, only the perceived weight was a significant performance constraint. In Experiment 2, the weight was perceived as heavier when the participants' actions were manipulated through cognitive interpretation. The increase in perceived weight appeared to be related to performance and intrinsically scaled to the action, even when the action was only mental rather than physical. The study's findings suggest that bodily experience and action are the basis for physical judgments and likely underlie other basic cognitive interpretations of sensory stimuli. This suggestion goes hand in hand with the biofunctional approaches which assume direct experience of the integrated wholeness of one's body is fundamental for developing other kinds of awareness. Different perspectives from oriental philosophy and psychology are also discussed. PMID:25741298

  10. 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. PMID:26021190

  11. 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

  12. 3D Traction Stresses Activate Protease-Dependent Invasion of Cancer Cells

    PubMed Central

    Aung, Aereas; Seo, Young N.; Lu, Shaoying; Wang, Yingxiao; Jamora, Colin; del Álamo, Juan C.; Varghese, Shyni

    2014-01-01

    Cell invasion and migration that occurs, for example, in cancer metastasis is rooted in the ability of cells to navigate through varying levels of physical constraint exerted by the extracellular matrix. Cancer cells can invade matrices in either a protease-independent or a protease-dependent manner. An emerging critical component that influences the mode of cell invasion is the traction stresses generated by the cells in response to the physicostructural properties of the extracellular matrix. In this study, we have developed a reference-free quantitative assay for measuring three-dimensional (3D) traction stresses generated by cells during the initial stages of invasion into matrices exerting varying levels of mechanical resistance. Our results show that as cells encounter higher mechanical resistance, a larger fraction of them shift to protease-mediated invasion, and this process begins at lower values of cell invasion depth. On the other hand, the compressive stress generated by the cells at the onset of protease-mediated invasion is found to be independent of matrix stiffness, suggesting that 3D traction stress is a key factor in triggering protease-mediated cancer cell invasion. At low 3D compressive traction stresses, cells utilize bleb formation to indent the matrix in a protease independent manner. However, at higher stress values, cells utilize invadopodia-like structures to mediate protease-dependent invasion into the 3D matrix. The critical value of compressive traction stress at the transition from a protease-independent to a protease-dependent mode of invasion is found to be ∼165 Pa. PMID:25468332

  13. 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

  14. 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. PMID:25638568

  15. 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

  16. 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

  17. 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

  18. 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.

  19. Affordable WDM components: the polymer solution

    NASA Astrophysics Data System (ADS)

    Eldada, Louay A.; Yin, Shing; Norwood, Robert A.; Yardley, James T.

    1998-02-01

    An advanced polymeric waveguide technology was developed for affordable WDM components that address the needs of both the Telecom and the Datacom industries. We engineered high- performance organic polymers that can be readily made into both multimode and single-mode optical waveguide structures of controlled numerical aperture and geometry. These materials are formed from highly-crosslinked acrylate monomers with specific linkages that determine properties such as flexibility, toughness, loss, and environmental stability. These monomers are intermiscible, providing for precise adjustment of the refractive index from 1.3 to 1.6. In polymer form, they exhibit state-of-the-art loss values, high thermal stability, high humidity resistance, low dispersion and low birefringence. Waveguides are formed photolithographically, with the liquid monomer mixture polymerizing upon illumination in the UV via either mask exposure or laser direct writing. A wide range of rigid and flexible substrates can be used, including glass, quartz, oxidized silicon, glass-filled epoxy printed circuit board substrate, and flexible polyimide film. Waveguiding structures measuring tens of inches in length can be produced on computer boards, and guides that are meters long can be printed on rolls of plastic. We describe the fabrication of both Bragg gratings and waveguide grating routes in our polymers for filtering and demultiplexing applications in Telecom WDM systems. In Datacom, we describe polymeric components that we produced for aerospace WDM sensor systems. The importance of CAD tools in designing WDM devices is emphasized in this work. We further discuss the low-cost manufacturing of WDM components in an industrial environment.

  20. 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

  1. 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.

  2. 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…

  3. 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…

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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…

  9. Providing Affordable Housing: Small Communities Benefit from Upgrading Dilapidated Homes.

    ERIC Educational Resources Information Center

    Hestekin, Kay

    1991-01-01

    Describes the Affordable Housing Opportunities Program (AHOP) created by the Eau Claire County Housing Authority in Wisconsin. The AHOP buys, renovates, and sells homes for prices below fair market value. This provides safe, sanitary housing for families who could not otherwise afford it. Describes the purchase, renovation, and sale of four…

  10. What's the Issue about Affordability of Public Higher Education?

    ERIC Educational Resources Information Center

    Goff, Donald Gary

    This study compared and contrasted data reports of two national policy centers on the affordability of public higher education. The study examined cost findings of the National Center for Educational Statistics (NCES) and the major affordability findings of the National Center for Public Policy and Higher Education (NCPPHE). Both policy centers…

  11. 24 CFR 92.254 - Qualification as affordable housing: Homeownership.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 1 2013-04-01 2013-04-01 false Qualification as affordable housing: Homeownership. 92.254 Section 92.254 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development HOME INVESTMENT PARTNERSHIPS PROGRAM Project Requirements § 92.254 Qualification as affordable...

  12. 24 CFR 92.254 - Qualification as affordable housing: Homeownership.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... application under 24 CFR part 597 has incorporated the type of market data described above, that submission... 24 Housing and Urban Development 1 2011-04-01 2011-04-01 false Qualification as affordable housing... Qualification as affordable housing: Homeownership. (a) Acquisition with or without rehabilitation. Housing...

  13. 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…

  14. 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.

  15. 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

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. 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. PMID:25316210

  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. Traction force microscopy in rapidly moving cells reveals separate roles for ROCK and MLCK in the mechanics of retraction.

    PubMed

    Morin, Timothy R; Ghassem-Zadeh, Sean A; Lee, Juliet

    2014-08-15

    Retraction is a major rate-limiting step in cell motility, particularly in slow moving cell types that form large stable adhesions. Myosin II dependent contractile forces are thought to facilitate detachment by physically pulling up the rear edge. However, retraction can occur in the absence of myosin II activity in cell types that form small labile adhesions. To investigate the role of contractile force generation in retraction, we performed traction force microscopy during the movement of fish epithelial keratocytes. By correlating changes in local traction stress at the rear with the area retracted, we identified four distinct modes of retraction. "Recoil" retractions are preceded by a rise in local traction stress, while rear edge is temporarily stuck, followed by a sharp drop in traction stress upon detachment. This retraction type was most common in cells generating high average traction stress. In "pull" type retractions local traction stress and area retracted increase concomitantly. This was the predominant type of retraction in keratocytes and was observed mostly in cells generating low average traction stress. "Continuous" type retractions occur without any detectable change in traction stress, and are seen in cells generating low average traction stress. In contrast, to many other cell types, "release" type retractions occur in keratocytes following a decrease in local traction stress. Our identification of distinct modes of retraction suggests that contractile forces may play different roles in detachment that are related to rear adhesion strength. To determine how the regulation of contractility via MLCK or Rho kinase contributes to the mechanics of detachment, inhibitors were used to block or augment these pathways. Modulation of MLCK activity led to the most rapid change in local traction stress suggesting its importance in regulating attachment strength. Surprisingly, Rho kinase was not required for detachment, but was essential for localizing

  3. 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.

  4. 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. PMID:25748431

  5. 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.

  6. 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

  7. The dependence of traction evolution on the earthquake source time function adopted in kinematic rupture models

    NASA Astrophysics Data System (ADS)

    Piatanesi, Alessio; Tinti, Elisa; Cocco, Massimo; Fukuyama, Eiichi

    2004-02-01

    We compute the temporal evolution of traction by solving the elasto-dynamic equation and by using the slip velocity history as a boundary condition on the fault plane. We use different source time functions to derive a suite of kinematic source models to image the spatial distribution of dynamic and breakdown stress drop, strength excess and critical slip weakening distance (Dc). Our results show that the source time functions, adopted in kinematic source models, affect the inferred dynamic parameters. The critical slip weakening distance, characterizing the constitutive relation, ranges between 30% and 80% of the total slip. The ratio between Dc and total slip depends on the adopted source time functions and, in these applications, is nearly constant over the fault. We propose that source time functions compatible with earthquake dynamics should be used to infer the traction time history.

  8. Traction force microscopy on soft elastic substrates: A guide to recent computational advances.

    PubMed

    Schwarz, Ulrich S; Soiné, Jérôme R D

    2015-11-01

    The measurement of cellular traction forces on soft elastic substrates has become a standard tool for many labs working on mechanobiology. Here we review the basic principles and different variants of this approach. In general, the extraction of the substrate displacement field from image data and the reconstruction procedure for the forces are closely linked to each other and limited by the presence of experimental noise. We discuss different strategies to reconstruct cellular forces as they follow from the foundations of elasticity theory, including two- versus three-dimensional, inverse versus direct and linear versus non-linear approaches. We also discuss how biophysical models can improve force reconstruction and comment on practical issues like substrate preparation, image processing and the availability of software for traction force microscopy. This article is part of a Special Issue entitled: Mechanobiology. PMID:26026889

  9. 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.

  10. 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).

  11. Laboratory testing of chloride 3ET205 6 volt traction battery

    NASA Astrophysics Data System (ADS)

    Hardin, Jasper E.

    1989-10-01

    The purpose of this report is to describe the testing performed on the Chloride 3ET205 6 volt traction battery by the INEL Battery Laboratory, to present the results and conclusions of this testing, and to make appropriate recommendations. The Chloride 3ET205 is a tubular plate lead-acid battery made in England by the Chloride Battery Company and imported into the U.S. The traction battery division of Chloride has been sold, although Chloride assured its customers that the 3ET205 would continue to be available for their consumption. The new owners of the factory are Tudor and Fulman of France. The joint venture company name is C. E. Ac. It is our understanding that all orders are to be sent to the factory at Salford Rd., Bolton, Lancashire, England BL5 1DD.

  12. A Conforming Multigrid Method for the Pure Traction Problem of Linear Elasticity: Mixed Formulation

    NASA Technical Reports Server (NTRS)

    Lee, Chang-Ock

    1996-01-01

    A multigrid method using conforming P-1 finite element is developed for the two-dimensional pure traction boundary value problem of linear elasticity. The convergence is uniform even as the material becomes nearly incompressible. A heuristic argument for acceleration of the multigrid method is discussed as well. Numerical results with and without this acceleration as well as performance estimates on a parallel computer are included.

  13. 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.

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. Setting a standard of affordability for health insurance coverage.

    PubMed

    Blumberg, Linda J; Holahan, John; Hadley, Jack; Nordahl, Katharine

    2007-01-01

    Recently, Massachusetts passed landmark legislation designed to expand health insurance coverage. This legislation includes a requirement that all adults enroll in a health insurance plan. This mandate takes effect only if an "affordable" plan is available. The definition of affordability for individuals and families of different incomes or circumstances is a critical decision in implementation and is relevant to any state or federal reform requiring individual premium or cost-sharing contributions, or both. This analysis was done to assist the policy design process in Massachusetts and delineates an empirically based approach to setting affordability standards. PMID:17548341

  19. 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.

  20. 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.

  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. Spatiotemporal dynamics of traction forces show three contraction centers in migratory neurons

    PubMed Central

    Jiang, Jian; Zhang, Zheng-hong; Yuan, Xiao-bin

    2015-01-01

    Traction force against the substrate is required for neuronal migration, but how it is generated and regulated remains controversial. Using traction force microscopy, we showed in cultured granule cells the coexistence of three distinct contraction centers (CCs) that are located at the distal and proximal regions of the leading process as well as at the trailing process, regions exhibiting high-level myosin-II activities. The CC activities depended on myosin-II, actin filaments, and microtubules, as well as substrate adhesion, and exhibited apparently independent fluctuation. The difference of strain energies associated with CC activities between leading versus trailing processes tightly correlated with the displacement of the soma at any given time. Application of brain-derived neurotrophic factor (BDNF) and Slit2, factors known to guide neuronal migration, at the leading process altered CC activities by regulating the small GTPases Cdc42 and RhoA, respectively, leading to forward and rearward soma translocation. These results delineate the multiple origins and spatiotemporal dynamics of the traction force underlying neuronal migration. PMID:26056143

  3. 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

  4. 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

  5. Modification of Cellular Cholesterol Content Affects Traction Force, Adhesion and Cell Spreading

    PubMed Central

    Norman, Leann L.; Oetama, Ratna J.; Dembo, Micah; Byfield, F.; Hammer, Daniel A.; Levitan, Irena; Aranda-Espinoza, Helim

    2011-01-01

    Cellular cholesterol is a critical component of the plasma membrane, and plays a key role in determining the physical properties of the lipid bilayer, such as elasticity, viscosity, and permeability. Surprisingly, it has been shown that cholesterol depletion increases cell stiffness, not due to plasma membrane stiffening, but rather, due to the interaction between the actin cytoskeleton and the plasma membrane. This indicates that traction stresses of the acto-myosin complex likely increase during cholesterol depletion. Here we use force traction microscopy to quantify the forces individual cells are exerting on the substrate, and total internal reflection fluorescence microscopy as well as interference reflection microscopy to observe cell–substrate adhesion and spreading. We show that single cells depleted of cholesterol produce larger traction forces and have large focal adhesions compared to untreated or cholesterol-enriched cells. Cholesterol depletion also causes a decrease in adhesion area for both single cells and monolayers. Spreading experiments illustrate a decrease in spreading area for cholesterol-depleted cells, and no effect on cholesterol-enriched cells. These results demonstrate that cholesterol plays an important role in controlling and regulating the cell–substrate interactions through the actin–plasma membrane complex, cell–cell adhesion, and spreading. PMID:21461187

  6. 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

  7. 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

  8. A hemidesmosomal protein regulates actin dynamics and traction forces in motile keratinocytes.

    PubMed

    Hiroyasu, Sho; Colburn, Zachary T; Jones, Jonathan C R

    2016-06-01

    During wound healing of the skin, keratinocytes disassemble hemidesmosomes and reorganize their actin cytoskeletons in order to exert traction forces on and move directionally over the dermis. Nonetheless, the transmembrane hemidesmosome component collagen XVII (ColXVII) is found in actin-rich lamella, situated behind the lamellipodium. A set of actin bundles, along which ColXVII colocalizes with actinin4, is present at each lamella. Knockdown of either ColXVII or actinin4 not only inhibits directed migration of keratinocytes but also relieves constraints on actin bundle retrograde movement at the site of lamella, such that actin bundle movement is enhanced more than 5-fold. Moreover, whereas control keratinocytes move in a stepwise fashion over a substrate by generating alternating traction forces, of up to 1.4 kPa, at each flank of the lamellipodium, ColXVII knockdown keratinocytes fail to do so. In summary, our data indicate that ColXVII-actinin4 complexes at the lamella of a moving keratinocyte regulate actin dynamics, thereby determining the direction of cell movement.-Hiroyasu, S., Colburn, Z. T., Jones, J. C. R. A hemidesmosomal protein regulates actin dynamics and traction forces in motile keratinocytes. PMID:26936359

  9. 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.

  10. Rho Mediates the Shear-Enhancement of Endothelial Cell Migration and Traction Force Generation

    PubMed Central

    Shiu, Yan-Ting; Li, Song; Marganski, William A.; Usami, Shunichi; Schwartz, Martin A.; Wang, Yu-Li; Dembo, Micah; Chien, Shu

    2004-01-01

    The migration of vascular endothelial cells in vivo occurs in a fluid dynamic environment due to blood flow, but the role of hemodynamic forces in cell migration is not yet completely understood. Here we investigated the effect of shear stress, the frictional drag of blood flowing over the cell surface, on the migration speed of individual endothelial cells on fibronectin-coated surfaces, as well as the biochemical and biophysical bases underlying this shear effect. Under static conditions, cell migration speed had a bell-shaped relationship with fibronectin concentration. Shear stress significantly increased the migration speed at all fibronectin concentrations tested and shifted the bell-shaped curve upwards. Shear stress also induced the activation of Rho GTPase and increased the traction force exerted by endothelial cells on the underlying substrate, both at the leading edge and the rear, suggesting that shear stress enhances both the frontal forward-pulling force and tail retraction. The inhibition of a Rho-associated kinase, p160ROCK, decreased the traction force and migration speed under both static and shear conditions and eliminated the shear-enhancement of migration speed. Our results indicate that shear stress enhances the migration speed of endothelial cells by modulating the biophysical force of tractions through the biochemical pathway of Rho-p160ROCK. PMID:15041692

  11. 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.

  12. 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.

  13. 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.

  14. Spatiotemporal dynamics of traction forces show three contraction centers in migratory neurons.

    PubMed

    Jiang, Jian; Zhang, Zheng-hong; Yuan, Xiao-bin; Poo, Mu-ming

    2015-06-01

    Traction force against the substrate is required for neuronal migration, but how it is generated and regulated remains controversial. Using traction force microscopy, we showed in cultured granule cells the coexistence of three distinct contraction centers (CCs) that are located at the distal and proximal regions of the leading process as well as at the trailing process, regions exhibiting high-level myosin-II activities. The CC activities depended on myosin-II, actin filaments, and microtubules, as well as substrate adhesion, and exhibited apparently independent fluctuation. The difference of strain energies associated with CC activities between leading versus trailing processes tightly correlated with the displacement of the soma at any given time. Application of brain-derived neurotrophic factor (BDNF) and Slit2, factors known to guide neuronal migration, at the leading process altered CC activities by regulating the small GTPases Cdc42 and RhoA, respectively, leading to forward and rearward soma translocation. These results delineate the multiple origins and spatiotemporal dynamics of the traction force underlying neuronal migration. PMID:26056143

  15. 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).

  16. 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

  17. 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

  18. 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.

  19. 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

  20. 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.

  1. LNG: Clean affordable energy for power and town gas in Asia

    SciTech Connect

    Williams, M.F.; Grant, C.W.; King, N.

    1998-02-01

    Some Asian countries such as Myanmar, Vietnam, and Indonesia are still at very low electricity consumption rates per capita, while others, such as Malaysia and Taiwan, are at much higher rates. What all Asian countries have in common is rapid growth in the demand for electricity. If the rising demand for additional electricity is not met, economic growth will be curtailed. However, all Asian countries face a major challenge in funding and constructing the required additional generating capacity fast enough to meet demand. Finding this amount of new capital is not going to be easy, and there will be much competition for scarce funds. The environmental challenge may be even greater than the financing hurdle. To date, most generation capacity in Asia has been coal based, and a significant amount of that is low technology and without flue gas desulfurization. The effect on the environment is already apparent. One argument has been that developing countries cannot afford the same standards of environmental performance as developed countries. With the levels of pollution that exist today, the question should be, can they afford not to? It has been estimated that pollution in China costs US$100 billion/a and that US$20 billion has to be spent over the next decade just to prevent worsening of pollution.

  2. 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.

  3. 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. PMID:23748944

  4. 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

  5. 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.

  6. Biosignal PI, an affordable open-source ECG and respiration measurement system.

    PubMed

    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

  7. 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

  8. 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

  9. 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

  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 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.

  12. 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.

  13. Imaging in-plane and normal stresses near an interface crack using traction force microscopy

    PubMed Central

    Xu, Ye; Engl, Wilfried C.; Jerison, Elizabeth R.; Wallenstein, Kevin J.; Hyland, Callen; Wilen, Larry A.; Dufresne, Eric R.

    2010-01-01

    Colloidal coatings, such as paint, are all around us. However, we know little about the mechanics of the film-forming process because the composition and properties of drying coatings vary dramatically in space and time. To surmount this challenge, we extend traction force microscopy to quantify the spatial distribution of all three components of the stress at the interface of two materials. We apply this approach to image stress near the tip of a propagating interface crack in a drying colloidal coating and extract the stress intensity factor. PMID:20696929

  14. 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.

  15. 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

  16. Conflict in the kitchen: Contextual modulation of responsiveness to affordances.

    PubMed

    Wokke, Martijn E; Knot, Sarah L; Fouad, Aisha; Richard Ridderinkhof, K

    2016-02-01

    Recently, human behavior has been considered the product of continuous interactions between perception, cognition and action in which "affordances" (action possibilities the environment has to offer) play an important role. Converging evidence suggests that multiple action possibilities simultaneously compete for further processing, while external and internal factors (e.g., incoming sensory information, predictions) bias this competition. In the present study we used a stop-task to investigate whether context is able to modulate the strength of the responsiveness to affordances. We therefore placed participants in an actual kitchen and workshop during electroencephalographic recordings. A faster response to context congruent objects demonstrated that the direct surrounding is able to affect responsiveness to affordances. In addition, when responses needed to be withheld, context congruent objects evoked greater response conflict as indicated by an enhanced N2 Event Related Potential (ERP) component. PMID:26821243

  17. 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

  18. 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

  19. 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

  20. Can Low-Income Americans Afford a Healthy Diet?

    PubMed Central

    Drewnowski, Adam; Eichelsdoerfer, Petra

    2010-01-01

    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. PMID:20368762

  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. A direct traction boundary integral equation method for three-dimension crack problems in infinite and finite domains

    NASA Astrophysics Data System (ADS)

    Xie, Guizhong; Zhang, Jianming; Huang, Cheng; Lu, Chenjun; Li, Guangyao

    2014-04-01

    This paper presents a direct traction boundary integral equation method (TBIEM) for three-dimensional crack problems. The TBIEM is based on the traction boundary integral equation (TBIE). The TBIE is collocated on both the external boundary and one of the crack surfaces. The displacements and tractions are used as unknowns on the external boundary and the relative crack opening displacements (CODs) are introduced as unknowns on the crack surface. In our implementation, all the surfaces of the considered structure are discretized into discontinuous elements to satisfy the continuity requirement for the existence of finite-part integrals, and special crack-front elements are constructed to capture the crack-tip behavior. To calculate the finite-part integrals, an adaptive singular integral technique is proposed. The stress intensity factors (SIFs) are computed through a modified COD extrapolation method. Numerical examples of SIFs computation are presented to demonstrate the accuracy and efficiency of our method.

  3. 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.

  4. 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.

  5. Bone transport using intramedullary fixation and a single flexible traction cable.

    PubMed

    Hyodo, A; Kotschi, H; Kambic, H; Muschler, G

    1996-04-01

    The transfixing wires used in the limb-lengthening and bone-transport procedures described by Ilizarov are the primary source of complications, including infection, restricted joint motion, and pain. In an attempt to eliminate the need for external fixation, a traction cable device was devised to perform a 3-cm bone transport in the canine femur using an interlocking intramedullary rod for fixation. Twelve dogs were divided into 2 groups. Transport began 7 days after osteotomy and continued at either 1 mm per day (n = 6) or 2 mm per day (n = 6). The in vivo peak force, resting force, and stiffness of the transport segment increased throughout distraction to a mean of 150 Newtons, 58 N, and 58 N per millimeter, respectively, at the time of docking. The regenerate and docking sites united in 10 of 12 dogs. Failure of the regenerate associated with deep infection around the rod occurred in 2 animals (17%). Modifications of this technique to reduce the risk of infection are discussed. This study confirms that intramedullary fixation is compatible with distraction osteogenesis and shows that a single traction cable can provide the force necessary for bone transport without transfixing wires in this setting. PMID:8998886

  6. 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

  7. Macrophages Mediate the Repair of Brain Vascular Rupture through Direct Physical Adhesion and Mechanical Traction.

    PubMed

    Liu, Chi; Wu, Chuan; Yang, Qifen; Gao, Jing; Li, Li; Yang, Deqin; Luo, Lingfei

    2016-05-17

    Hemorrhagic stroke and brain microbleeds are caused by cerebrovascular ruptures. Fast repair of such ruptures is the most promising therapeutic approach. Due to a lack of high-resolution in vivo real-time studies, the dynamic cellular events involved in cerebrovascular repair remain unknown. Here, we have developed a cerebrovascular rupture system in zebrafish by using multi-photon laser, which generates a lesion with two endothelial ends. In vivo time-lapse imaging showed that a macrophage arrived at the lesion and extended filopodia or lamellipodia to physically adhere to both endothelial ends. This macrophage generated mechanical traction forces to pull the endothelial ends and facilitate their ligation, thus mediating the repair of the rupture. Both depolymerization of microfilaments and inhibition of phosphatidylinositide 3-kinase or Rac1 activity disrupted macrophage-endothelial adhesion and impaired cerebrovascular repair. Our study reveals a hitherto unexpected role for macrophages in mediating repair of cerebrovascular ruptures through direct physical adhesion and mechanical traction. PMID:27156384

  8. Coordinated vehicle traction control based on engine torque and brake pressure under complicated road conditions

    NASA Astrophysics Data System (ADS)

    Kang, Mingxin; Li, Liang; Li, Hongzhi; Song, Jian; Han, Zongqi

    2012-09-01

    Vehicle traction control system has been developed to enhance the traction capability and the direction stability of the driving wheels through the tyre slip ratio regulation. Under normal situations, if the tyre slip ratio exceeds a certain threshold, the slip ratio of the driving wheel is regulated by the coupled interaction of the engine torque and the active brake pressure. In order to obtain the best driving performance on a road under complicated friction conditions, the driving torque and the active brake pressure, need to be decoupled and adjusted to avoid penalisation of each other. In this paper, a coordinated cascade control method with two sliding-mode variable structure controllers is presented. In this control method, the driving wheel slip ratio is regulated by adjusting the engine torque and the wheel brake pressure. Through the sliding-mode controller, the engine torque is tuned to achieve the maximum driving acceleration and then the active brake pressure is applied to the slipped wheel for further modification of the wheel slip ratio. The advantage of this control method is that through proper regulation, the conflict between the two control inputs could be avoided. Finally, the simulation results validate the effectiveness of the proposed method.

  9. Use of traction during magnetic resonance imaging of caudal cervical spondylomyelopathy ("wobbler syndrome") in the dog.

    PubMed

    Penderis, Jacques; Dennis, Ruth

    2004-01-01

    Cervical spondylomyelopathy or "wobbler syndrome" is a well-defined disorder of large-breed dogs, characterized by a compressive lesion affecting the cervical spinal cord that in many dogs may have a dynamic component. Determination of whether this dynamic component is present is important in the decision-making process as regards therapeutic intervention. Despite a significant risk of neurologic deterioration following myelography in some large dogs affected by wobbler syndrome, myelography is considered an essential part of the assessment, primarily as it allows assessment of whether a dynamic compression exists. This same neurologic deterioration is not apparent following magnetic resonance (MR) imaging; however, the use of MR imaging in the investigation of wobbler syndrome has thus far been limited by the inability to perform the traction studies required to ascertain whether a dynamic component to the spinal cord compression exists. This paper presents a technique of applying traction during MR imaging of the cervical spine to reduce a dynamic wobbler syndrome lesion. PMID:15200258

  10. α1 -AR agonist induced piloerection protects against the development of traction alopecia.

    PubMed

    Goren, Andy; Shapiro, Jerry; Sinclair, Rodney; Kovacevic, Maja; McCoy, John

    2016-05-01

    Traction alopecia is hair loss that occurs after persistent pulling (e.g., during cosmetic procedures) on the roots of hair over time. Unlike plucking, which is painful, persistent pulling may go unnoticed until a patient presents with either bald spots or diffuse telogen shedding. Each hair follicle in the scalp contains an arrector pili muscle that, when contracted, erects the hair. The smooth muscle in the arrector pili expresses α1 adrenergic receptors (α1 -AR). As such, we hypothesized that contraction of the arrector pili muscle via an α1 -AR agonist would increase the threshold of force required to pluck hair during cosmetic procedures. Female subjects, ages 18-40, were recruited to study the effect of topically applied phenylephrine, a selective α1 -AR agonist, on epilation force and hair shedding during cosmetic procedures. In our blinded study, 80% of subjects demonstrated reduced shedding on days using phenylephrine compared to days using a placebo solution. The average reduction in hair loss was approximately 42%. In addition, the force threshold required for epilation increased by approximately 172% following topical phenylephrine application. To our knowledge this is the first study demonstrating the utility of α1 -AR agonists in the treatment of traction alopecia and hair shedding during cosmetic procedures. PMID:26678522

  11. 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.

  12. 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

  13. Thermoelastic finite element analysis of subsurface cracking due to sliding surface traction

    SciTech Connect

    Cho, S.S.; Komvopoulos, K.

    1997-01-01

    A linear elastic fracture mechanics analysis of subsurface crack propagation in a half-space subjected to moving thermomechanical surface traction was performed using the finite element method. The effect of frictional heating at the sliding surface on the crack growth behavior is analyzed in terms of the coefficient of friction, crack length-to-depth ratio, and Peclet number. The crack propagation characteristics are interpreted in light of results for the directions and magnitudes of the maximum shear and tensile stress intensity factor ranges, respectively. It is shown that, while frictional heating exhibits a negligible effect on the crack propagation direction, it increases the in-plane crack growth rate and reduces the critical crack length at the onset of out-of-plane crack growth at the right tip due to the tensile mechanism (kink formation). The effect of frictional heating becomes more pronounced with increasing contact friction, crack length-to-depth ratio, and Peclet number. Crack mechanism maps showing the occurrence of opening, slip, and stick regions between the crack surfaces are presented for different values of crack length-to-depth ratio, coefficient of friction, and position of thermomechanical surface traction.

  14. External Fixation vs. Skeletal Traction for Treatment of Intertrochanteric Fractures in the Elderly

    PubMed Central

    Kazemian, Gholam Hossein; Emami, Mohammad; Manafi, Alireza; Najafi, Farideh; Najafi, Mohammad Amin

    2016-01-01

    Background Hip fractures are one of the causes of disability amongst elderly patients. External fixator and skeletal traction are two modes of treatment. Objectives The aim of this study is to compare two different treatment modes for intertrochanteric fractures in elderly patients. Patients and Methods Sixty elderly patients with intertrochanteric fractures were randomized for treatment with either skeletal traction (Group A) or an external fixation (Group B). In this study patients at least 60 years of age, with AO/OTA A1 or A2 type fracture and intertrochanteric fracture as a result of minor trauma, were enrolled. Results Acceptable reduction was achieved in eight and 26 patients of group A and B, respectively. The mean duration of hospitalization in Group A and Group B was 14.3 ± 1.1 and 2.2 ± 0.6 days, respectively. Significant differences between the two groups were observed, regarding acceptable reduction and duration of hospitalization. Less pain was observed in group B, at five days and twelve months after surgery; the average HHS was 57 and 66, in group A and B, respectively (P > 0.05). Conclusions Treatment with an external fixator is an effective treatment modality for intertrochanteric fractures in elderly high-risk patients. The advantages include rapid and simple application, insignificant blood loss, less radiation exposure, adequate fixation, pain reduction, early discharge from the hospital, low cost and more favorable functional outcome. PMID:27218039

  15. 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

  16. 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.

  17. 77 FR 33133 - Patient Protection and Affordable Care Act; Data Collection To Support Standards Related to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-05

    ... HUMAN SERVICES 45 CFR Part 156 RIN 0938-AR36 Patient Protection and Affordable Care Act; Data Collection... the Patient Protection and Affordable Care Act (Affordable Care Act), which directs the Secretary of... Services (the Secretary). The Affordable Care Act directs that the EHB reflect the scope of...

  18. 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 Act....

  19. 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...

  20. 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…

  1. 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…

  2. 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…

  3. 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

  4. 12 CFR 1282.14 - Special Affordable Housing Goal.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Insurance Fund; and (C) Subject to, and have received at least a satisfactory performance evaluation rating... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Special Affordable Housing Goal. 1282.14 Section 1282.14 Banks and Banking FEDERAL HOUSING FINANCE AGENCY HOUSING GOALS AND MISSION...

  5. 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…

  6. Music Composition Lessons: The Multimodal Affordances of Technology

    ERIC Educational Resources Information Center

    Gall, Marina; Breeze, Nick

    2005-01-01

    This article investigates the multimodal affordances presented by music software and how it can provide new opportunities for students to engage with composition work in the classroom. It seeks to broaden the scope of current research into classroom composition using technology, through a study of students' environments and compositional processes…

  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. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 24 CFR 1006.201 - Eligible affordable housing activities.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... URBAN DEVELOPMENT NATIVE HAWAIIAN HOUSING BLOCK GRANT PROGRAM Eligible Activities § 1006.201 Eligible... 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...

  14. 24 CFR 1006.201 - Eligible affordable housing activities.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... URBAN DEVELOPMENT NATIVE HAWAIIAN HOUSING BLOCK GRANT PROGRAM Eligible Activities § 1006.201 Eligible... 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...

  15. 24 CFR 92.254 - Qualification as affordable housing: Homeownership.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Zone or Enterprise Community application under 24 CFR part 597 has incorporated the type of market data... 24 Housing and Urban Development 1 2014-04-01 2014-04-01 false Qualification as affordable housing: Homeownership. 92.254 Section 92.254 Housing and Urban Development Office of the Secretary, Department...

  16. 24 CFR 1006.201 - Eligible affordable housing activities.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... URBAN DEVELOPMENT NATIVE HAWAIIAN HOUSING BLOCK GRANT PROGRAM Eligible Activities § 1006.201 Eligible... 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...

  17. 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...

  18. 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...

  19. 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.

  20. 24 CFR 401.408 - Affordability and use restrictions required.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Development (Continued) OFFICE OF HOUSING AND OFFICE OF MULTIFAMILY HOUSING ASSISTANCE RESTRUCTURING, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT MULTIFAMILY HOUSING MORTGAGE AND HOUSING ASSISTANCE RESTRUCTURING PROGRAM (MARK-TO-MARKET) Restructuring Plan § 401.408 Affordability and use restrictions required....

  1. 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…

  2. 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.

  3. 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 Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR PUBLIC AND INDIAN HOUSING, DEPARTMENT OF HOUSING...

  4. 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…

  5. 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…

  6. 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…

  7. 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…

  8. 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...

  9. 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...

  10. 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…

  11. 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

  12. Toward Affordability: Policy Recommendations for Virginia Higher Education

    ERIC Educational Resources Information Center

    State Council of Higher Education for Virginia, 2009

    2009-01-01

    In its 2007-13 strategic plan, Advancing Virginia: Access, Alignment, Investment, the State Council highlighted 12 strategic higher education initiatives that it believed were necessary to ensure Virginia's future. Key among these goals was improvement of the affordability of a college education in the Commonwealth. Recent events have reinforced…

  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. PMID:22065686

  14. 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…

  15. 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…

  16. 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...

  17. 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...

  18. 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...

  19. 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…

  20. 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…

  1. Limb apraxia and the “affordance competition hypothesis”

    PubMed Central

    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

  2. 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…

  3. Evaluation of Intravitreal Ranibizumab on the Surgical Outcome for Diabetic Retinopathy With Tractional Retinal Detachment.

    PubMed

    Dong, Feng; Yu, Chenying; Ding, Haiyuan; Shen, Liping; Lou, Dinghua

    2016-02-01

    This study aims to investigate intravitreal injection of Ranibizumab on the surgical outcome for diabetic patients who had tractional retinal detachment but did not receive any preoperative retinal photocoagulation.Ninety-seven patients (97 eyes) who had diabetic retinopathy with tractional retinal detachment were enrolled to receive 23-G pars plana vitrectomy (PPV). They were assigned to an experimental group (Group I, n = 47 eyes) and a control group (Group II, n = 50 eyes). The patients in Group I were given 1 injection of intravitreal Ranibizumab (Lucentis 0.5 mg/0.05 mL) 1 week before surgery, whereas those in Group II went down to surgery directly. Follow-ups were performed for 6 months to 3 years (16 ± 6 months), and indicators observed included postoperative best-corrected visual acuity, complications, and retinal thickness in the macula measured by optical coherence tomography.In Group I, BCVA improved from logMAR 1.92 ± 0.49 to logMAR 0.81 ± 0.39 following surgery, whereas in Group II, BCVA improved from logMAR 1.91 ± 0.49 to logMAR 0.85 ± 0.41. There was significant postoperative gain in vision, but there was no significant difference between the 2 groups at postoperative follow-up visits. The mean duration of vitrectomy in Group I and Group II was (40 ± 7) minutes and (53 ± 9) minutes, respectively, with significant difference. Iatrogenic breaks were noted in 5 eyes (11%) in the experimental group and 17 eyes (34%) in the control group; the difference was significant. The retinal thickness in the macula measured by OCT was (256 ± 44) μm and (299 ± 84) μm in Group I and Group II respectively with significant difference. Besides, there were significantly more eyes in Group II that required silicone oil tamponade and postoperative retinal photocoagulation.23-G PPV combined with intravitreal tamponade and panretinal photocoagulation still remains an effective regimen for the treatment of

  4. Evaluation of Intravitreal Ranibizumab on the Surgical Outcome for Diabetic Retinopathy With Tractional Retinal Detachment

    PubMed Central

    Dong, Feng; Yu, Chenying; Ding, Haiyuan; Shen, Liping; Lou, Dinghua

    2016-01-01

    Abstract This study aims to investigate intravitreal injection of Ranibizumab on the surgical outcome for diabetic patients who had tractional retinal detachment but did not receive any preoperative retinal photocoagulation. Ninety-seven patients (97 eyes) who had diabetic retinopathy with tractional retinal detachment were enrolled to receive 23-G pars plana vitrectomy (PPV). They were assigned to an experimental group (Group I, n = 47 eyes) and a control group (Group II, n = 50 eyes). The patients in Group I were given 1 injection of intravitreal Ranibizumab (Lucentis 0.5 mg/0.05 mL) 1 week before surgery, whereas those in Group II went down to surgery directly. Follow-ups were performed for 6 months to 3 years (16 ± 6 months), and indicators observed included postoperative best-corrected visual acuity, complications, and retinal thickness in the macula measured by optical coherence tomography. In Group I, BCVA improved from logMAR 1.92 ± 0.49 to logMAR 0.81 ± 0.39 following surgery, whereas in Group II, BCVA improved from logMAR 1.91 ± 0.49 to logMAR 0.85 ± 0.41. There was significant postoperative gain in vision, but there was no significant difference between the 2 groups at postoperative follow-up visits. The mean duration of vitrectomy in Group I and Group II was (40 ± 7) minutes and (53 ± 9) minutes, respectively, with significant difference. Iatrogenic breaks were noted in 5 eyes (11%) in the experimental group and 17 eyes (34%) in the control group; the difference was significant. The retinal thickness in the macula measured by OCT was (256 ± 44) μm and (299 ± 84) μm in Group I and Group II respectively with significant difference. Besides, there were significantly more eyes in Group II that required silicone oil tamponade and postoperative retinal photocoagulation. 23-G PPV combined with intravitreal tamponade and panretinal photocoagulation still remains an effective regimen for the

  5. Model for adhesion clutch explains biphasic relationship between actin flow and traction at the cell leading edge

    NASA Astrophysics Data System (ADS)

    Craig, Erin M.; Stricker, Jonathan; Gardel, Margaret; Mogilner, Alex

    2015-05-01

    Cell motility relies on the continuous reorganization of a dynamic actin-myosin-adhesion network at the leading edge of the cell, in order to generate protrusion at the leading edge and traction between the cell and its external environment. We analyze experimentally measured spatial distributions of actin flow, traction force, myosin density, and adhesion density in control and pharmacologically perturbed epithelial cells in order to develop a mechanical model of the actin-adhesion-myosin self-organization at the leading edge. A model in which the F-actin network is treated as a viscous gel, and adhesion clutch engagement is strengthened by myosin but weakened by actin flow, can explain the measured molecular distributions and correctly predict the spatial distributions of the actin flow and traction stress. We test the model by comparing its predictions with measurements of the actin flow and traction stress in cells with fast and slow actin polymerization rates. The model predicts how the location of the lamellipodium-lamellum boundary depends on the actin viscosity and adhesion strength. The model further predicts that the location of the lamellipodium-lamellum boundary is not very sensitive to the level of myosin contraction.

  6. 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

  7. 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

  8. Spontaneous Closure of a Full-Thickness Macular Hole Associated with Proliferative Diabetic Retinopathy and Persistent Vitreomacular Traction

    PubMed Central

    Reinherz, Benjamin J.; Rubin, Jeffrey S.

    2016-01-01

    Diabetic retinopathy worsens the prognosis of macular holes compared to those of idiopathic etiology. While spontaneous closure of idiopathic macular holes is a well-documented phenomenon, spontaneous closure of macular holes associated with proliferative diabetic retinopathy is rare. We report a case of spontaneous closure of a macular hole associated with proliferative diabetic retinopathy and persistent vitreomacular traction. PMID:27099607

  9. Directional control of lamellipodia extension by constraining cell shape and orienting cell tractional forces

    NASA Technical Reports Server (NTRS)

    Parker, Kevin Kit; Brock, Amy Lepre; Brangwynne, Cliff; Mannix, Robert J.; Wang, Ning; Ostuni, Emanuele; Geisse, Nicholas A.; Adams, Josephine C.; Whitesides, George M.; Ingber, Donald E.

    2002-01-01

    Directed cell migration is critical for tissue morphogenesis and wound healing, but the mechanism of directional control is poorly understood. Here we show that the direction in which cells extend their leading edge can be controlled by constraining cell shape using micrometer-sized extracellular matrix (ECM) islands. When cultured on square ECM islands in the presence of motility factors, cells preferentially extended lamellipodia, filopodia, and microspikes from their corners. Square cells reoriented their stress fibers and focal adhesions so that tractional forces were concentrated in these corner regions. When cell tension was dissipated, lamellipodia extension ceased. Mechanical interactions between cells and ECM that modulate cytoskeletal tension may therefore play a key role in the control of directional cell motility.

  10. Visualizing the interior architecture of focal adhesions with high-resolution traction maps.

    PubMed

    Morimatsu, Masatoshi; Mekhdjian, Armen H; Chang, Alice C; Tan, Steven J; Dunn, Alexander R

    2015-04-01

    Focal adhesions (FAs) are micron-sized protein assemblies that coordinate cell adhesion, migration, and mechanotransduction. How the many proteins within FAs are organized into force sensing and transmitting structures is poorly understood. We combined fluorescent molecular tension sensors with super-resolution light microscopy to visualize traction forces within FAs with <100 nm spatial resolution. We find that αvβ3 integrin selectively localizes to high force regions. Paxillin, which is not generally considered to play a direct role in force transmission, shows a higher degree of spatial correlation with force than vinculin, talin, or α-actinin, proteins with hypothesized roles as force transducers. These observations suggest that αvβ3 integrin and paxillin may play important roles in mechanotransduction. PMID:25730141

  11. Vinculin-dependent actin bundling regulates cell migration and traction forces

    PubMed Central

    Jannie, Karry M.; Ellerbroek, Shawn M.; Zhou, Dennis W.; Chen, Sophia; Crompton, David J.; García, Andrés J.; DeMali, Kris A.

    2015-01-01

    Vinculin binding to actin filaments is thought to be critical for force transduction within a cell, but direct experimental evidence to support this conclusion has been limited . In this study, we found mutation (R1049E) of the vinculin tail impairs its ability to bind F-actin, stimulate actin polymerization, and bundle F-actin in vitro. Further , mutant (R1049E) vinculin expressing cells are altered in cell migration, which is accompanied by changes in cell adhesion, cell spreading, and cell generation of traction forces, providing direct evidence for the critical role of vinculin in mechanotransduction at adhesion sites. Lastly, we herein discuss the viability of models detailing the F-actin-binding surface on vinculin in context of our mutational analysis. PMID:25358683

  12. Harness Traction Technique (HARNESS): Novel Method for Controlling the Transection Plane During Laparoscopic Hepatectomy.

    PubMed

    Itano, Osamu; Oshima, Go; Kitago, Minoru; Suzuki, Keiichi; Hayatsu, Shigeo; Shinoda, Masahiro; Abe, Yuta; Hibi, Taizo; Yagi, Hiroshi; Ikoma, Naruhiko; Aiko, Satoshi; Kitagawa, Yuko

    2015-08-01

    We present our experience using a novel method for controlling the transection plane, which we termed as the Harness Traction Technique (HARNESS) and evaluate its usefulness. From May 2009 to March 2012, laparoscopic hepatectomies using HARNESS were performed on 35 patients. After the superficial hepatic parenchyma on the line was transected at 1 to 2 cm depth, 5 mm tape was placed along the groove of the line and tied to prevent it from slipping off. Tape was tied and pulled using a forceps toward the best direction for minimizing the bleeding, moving the transection point to the appropriate position and creating good tension for parenchymal transection at the transection point. There were no conversions to laparotomy or intraoperative complications. HARNESS is useful for controlling the dissection line during laparoscopic hepatectomy, leading to precise and safe laparoscopic liver parenchymal dissection. PMID:26121541

  13. First-order system least squares for the pure traction problem in planar linear elasticity

    SciTech Connect

    Cai, Z.; Manteuffel, T.; McCormick, S.; Parter, S.

    1996-12-31

    This talk will develop two first-order system least squares (FOSLS) approaches for the solution of the pure traction problem in planar linear elasticity. Both are two-stage algorithms that first solve for the gradients of displacement, then for the displacement itself. One approach, which uses L{sup 2} norms to define the FOSLS functional, is shown under certain H{sup 2} regularity assumptions to admit optimal H{sup 1}-like performance for standard finite element discretization and standard multigrid solution methods that is uniform in the Poisson ratio for all variables. The second approach, which is based on H{sup -1} norms, is shown under general assumptions to admit optimal uniform performance for displacement flux in an L{sup 2} norm and for displacement in an H{sup 1} norm. These methods do not degrade as other methods generally do when the material properties approach the incompressible limit.

  14. Design considerations for attaining 200-knot test velocities at the aircraft landing loads and traction facility

    NASA Technical Reports Server (NTRS)

    Giles, G. L.; Stubbs, S. M.

    1979-01-01

    Design studies are presented which consider the important parameters in providing 200 knot test velocities at the landing loads and traction facility. Two major components of this facility, the hydraulic jet catapult and the test carriage structure, are considered. Suitable factors are determined to correlate analytical data for characteristics of the hydraulic jet catapult with data measured from the existing catapult system. The resulting equations are used to calculate test velocities for a range of jet nozzle diameters and carriage masses with both the current 122 m and an increased 183 m catapult stroke. Using the catapult characteristics, a target design point is selected and a carriage structure is sized to meet the target point strength requirements.

  15. A Review of Current Management of Vitreomacular Traction and Macular Hole

    PubMed Central

    García-Layana, Alfredo; García-Arumí, José; Ruiz-Moreno, José M.; Arias-Barquet, Lluís; Cabrera-López, Francisco; Figueroa, Marta S.

    2015-01-01

    The paper presents a review of the sequence of events of posterior vitreous detachment (PVD), vitreomacular adhesion (VMA), vitreomacular traction (VMT), and macular hole (MH) from their pathophysiological aspects, clinical features, diagnostic implications, and current management strategies. A treatment algorithm to be used in clinical practice in patients with VMA, VMT, and MH based on the presence of symptoms, visual acuity, associated epiretinal membrane, and width of the vitreous attachment is presented. Observation, pharmacologic vitreolysis with ocriplasmin, and surgical treatment are positioned as treatment options in the different steps of the therapeutic algorithm, with clear indications of the paths to be followed according to the initial presenting manifestations and the patient's clinical course. PMID:25821592

  16. 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

  17. 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

  18. Hoffmann-reflex is delayed during 6 degree head-down tilt with balanced traction

    NASA Technical Reports Server (NTRS)

    Haruna, Y.; Styf, J. R.; Kahan, N.; Hargens, A. R.

    1999-01-01

    BACKGROUND: Increased spinal height due to the lack of of axial compression on spinal structures in microgravity may stretch the spinal cord, cauda equina, nerve roots, and paraspinal tissues. HYPOTHESIS: Exposure to simulated microgravity causes dysfunction of nerve roots so that the synaptic portion of the Achilles tendon reflex is delayed. METHODS: Six healthy male subjects were randomly divided into two groups with three in each group. The subjects in the first group underwent horizontal bed rest (HBR) for three days. After a two week interval they underwent bed rest in a position of head-down tilt with balanced traction (HDT). So that each subject could serve as his own control, the second group was treated identically but in opposite order. Bilateral F waves and H-reflexes were measured daily (18:30-20:30) on all subjects placed in a prone position. RESULTS: By means of ANOVA, differences between HDT and HBR were observed only in M-latency and F-ratio, not in F-latency, central latency, and H-latency. Differences during the course of the bed rest were observed in M-latency and H-latency only. Tibial H latency was significantly lengthened in HDT group on day 2 and 3, although no significant difference between HDT and HBR was observed. CONCLUSION: The monosynaptic reflex assessed by H-reflex was delayed during 6 degree HDT with traction. The exact mechanism of this delay and whether the change was due to lengthening of the lower part of the vertebrae remain to be clarified.

  19. Development of a novel liquid crystal based cell traction force transducer system.

    PubMed

    Soon, C F; Youseffi, M; Berends, R F; Blagden, N; Denyer, M C T

    2013-01-15

    Keratinocyte traction forces play a crucial role in wound healing. The aim of this study was to develop a novel cell traction force (CTF) transducer system based on cholesteryl ester liquid crystals (LC). Keratinocytes cultured on LC induced linear and isolated deformation lines in the LC surface. As suggested by the fluorescence staining, the deformation lines appeared to correlate with the forces generated by the contraction of circumferential actin filaments which were transmitted to the LC surface via the focal adhesions. Due to the linear viscoelastic behavior of the LC, Hooke's equation was used to quantify the CTFs by associating Young's modulus of LC to the cell induced stresses and biaxial strain in forming the LC deformation. Young's modulus of the LC was profiled by using spherical indentation and determined at approximately 87.1±17.2kPa. A new technique involving cytochalasin-B treatment was used to disrupt the intracellular force generating actin fibers, and consequently the biaxial strain in the LC induced by the cells was determined. Due to the improved sensitivity and spatial resolution (∼1μm) of the LC based CTF transducer, a wide range of CTFs was determined (10-120nN). These were found to be linearly proportional to the length of the deformations. The linear relationship of CTF-deformations was then applied in a bespoke CTF mapping software to estimate CTFs and to map CTF fields. The generated CTF map highlighted distinct distributions and different magnitude of CTFs were revealed for polarized and non-polarized keratinocytes. PMID:22809522

  20. Penile traction therapy for Peyronie’s disease—what’s the evidence?

    PubMed Central

    Ipekci, Tumay

    2016-01-01

    Penile traction therapy (PTT) is a new therapeutic option for men with Peyronie’s disease (PD). However, it has a long history of use in other fields of medicine including bone, skin, skeletal muscle, and Dupuytren’s. Mechanotransduction, or gradual expansion of tissue by traction, leads to the formation of new collagen tissue by cellular proliferation. As a molecular result, continuous extension of the fibrous plaque causes significant increases in collagenase and metalloproteinases, and, ultimately, to fibrous plaque softening and extension. This hypothetical knowledge has been supported by recent well designed experimental studies. Furthermore, several clinical papers have provided promising results on the use of PTT in PD patients. It has been shown in some series that the use of PTT significantly increases flaccid and stretched penile lengths and results in significant penile curvature improvement when compared to baseline. Furthermore, the use of PTT concomitantly with either verapamil or interferon α-2b has also been shown to be an effective therapy. Additionally, the beneficial effect of PTT on penile length before or after penile surgery in men with corporal fibrosis has been described. Finally, as a minimally invasive alternative treatment option to penile augmentation surgery in men with dysmorphophobia, PTT use has shown promising results by several experts. Studies have shown that PTT provides an acceptable, minimally invasive method that can produce effective and durable lengthening of the penis in men complaining of a small/short penis. There are, however, several criticisms related to the designs of the reported studies, such as small sample size and selection bias. Well-designed studies with larger numbers of patients and longer follow-up periods are, however, needed to establish the true benefits of PTT. PMID:27298777

  1. Transvenous Lead Extraction via the Inferior Approach Using a Gooseneck Snare versus Simple Manual Traction

    PubMed Central

    Jo, Uk; Hwang, You-Mi; Lee, Ji-Hyun; Kim, Min-Su; Choi, Hyung-Oh; Lee, Woo-Seok; Kwon, Chang-Hee; Ko, Gi-Young; Yoon, Hyun-Ki; Nam, Gi-Byoung; Choi, Kee-Joon; Kim, You-Ho

    2016-01-01

    Background and Objectives The number of patients with cardiac implantable electronic devices needing lead extraction is increasing for various reasons, including infections, vascular obstruction, and lead failure. We report our experience with transvenous extraction of pacemaker and defibrillator leads via the inferior approach of using a gooseneck snare as a first-line therapy and compare extraction using a gooseneck snare with extraction using simple manual traction. Subjects and Methods The study included 23 consecutive patients (43 leads) who underwent transvenous lead extraction using a gooseneck snare (group A) and 10 consecutive patients (17 leads) who underwent lead extraction using simple manual traction (group B). Patient characteristics, indications, and outcomes were analyzed and compared between the groups. Results The dwelling time of the leads was longer in group A (median, 121) than in group B (median, 56; p=0.000). No differences were noted in the overall procedural success rate (69.6% vs. 70%), clinical procedural success rate (82.6% vs. 90%), and lead clinical success rate (86% vs. 94.1%) between the groups. The procedural success rates according to lead type were 89.2% and 100% for pacing leads and 66.7% and 83.3% for defibrillator leads in groups A and B, respectively. Major complications were noted in 3 (mortality in 1) patients in group A and 2 patients in group B. Conclusion Transvenous extraction of pacemaker leads via an inferior approach using a gooseneck snare was both safe and effective. However, stand-alone transvenous extraction of defibrillator leads using the inferior approach was suboptimal. PMID:27014349

  2. 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.

  3. 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

  4. 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.

  5. Clinical Preventive Services Coverage and the Affordable Care Act

    PubMed Central

    Fox, Jared B.; Shaw, Frederic E.

    2016-01-01

    The Affordable Care Act requires many health plans to provide coverage for certain recommended clinical preventive services without charging copays or deductible payments. This provision could lead to greater uptake of many services that can improve health and save lives. Although the coverage provision is broad, there are many caveats that also apply. It is important for providers and public health professionals to understand the nuances of the coverage rules to help maximize their potential to improve population health. PMID:25393173

  6. 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.

  7. Chrysler to race hybrid electric-LNG car

    SciTech Connect

    1994-03-07

    Chrysler Corp. hopes to race a hybrid electric-liquefied natural gas car in the Le Mans in 1995. Preparing for a racing program will speed technological advances that could take years under a regular development program. The car converts LNG to electricity with a two-turbine alternator that powers an electric traction motor. Power not used immediately is placed in reserve in an ultra-high-speed carbon-fiber flywheel, which also captures kinetic energy at braking. Even with the accelerated race program, Chrysler says it will likely be the next century before hybrid technology will make it into production cars.

  8. 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.

  9. Phase II CRADA ORNL99-0568 Report : Developing Transmission-Less Inverter Drive Systems for Axial-Gap Permanent magnet Accessory and Traction Motors and Generators

    SciTech Connect

    McKeever, J.W.

    2001-08-06

    Researchers of the Oak Ridge National Laboratory's (ORNLs) Power Electronics and Electric Machine Research Center (PEEMRC) collaborated with Visual Computing Systems (VCS) to develop an electric axial-gap permanent magnet (PM) motor controlled by a self-sensing inverter for driving vehicle accessories such as power steering, air conditioning, and brakes. VCS designed an 8 kW motor based on their Segmented Electromagnetic Array (SEMA) technology. ORNL designed a 10 kW inverter to fit within the volume of a housing, which had been integrated with the motor. This modular design was pursued so that multiple modules could be used for higher power applications. ORNL built the first inverter under the cooperative research and development agreement (CRADA) ORNL 98-0514 and drove a refurbished Delta motor with no load during the Merit Review at ORNL on Monday, May 17, 1999. Inverter circuitry and instructions for assembling the inverters were sent to VCS. A report was prepared and delivered during the Future Car Congress in April 2000, at Arlington, Virginia. Collaboration continued under CRADA ORNL 99-0568 as VCS designed and built a SEMA motor with a dual coil platter to be the traction motor for an electric truck. VCS and ORNL assembled two 45 kW inverters. Each inverter drove one coil, which was designed to deliver 15 kW continuous power and 45 kW peak power for 90 s. The vehicle was road tested as part of the Future Truck Competition. A report was prepared and delivered during the PCIM in October 2000, at Boston, Massachusetts.

  10. 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.

  11. 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.

  12. 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.

  13. 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 Outreach and Assistance Program Funding for Title VI Native American Programs Purpose of Notice: Availability of funding opportunity announcement. Funding Opportunity Title/Program Name: Affordable Care...

  14. Delivering affordable cancer care in high-income countries.

    PubMed

    Sullivan, Richard; Peppercorn, Jeffrey; Sikora, Karol; Zalcberg, John; Meropol, Neal J; Amir, Eitan; Khayat, David; Boyle, Peter; Autier, Philippe; Tannock, Ian F; Fojo, Tito; Siderov, Jim; Williamson, Steve; Camporesi, Silvia; McVie, J Gordon; Purushotham, Arnie D; Naredi, Peter; Eggermont, Alexander; Brennan, Murray F; Steinberg, Michael L; De Ridder, Mark; McCloskey, Susan A; Verellen, Dirk; Roberts, Terence; Storme, Guy; Hicks, Rodney J; Ell, Peter J; Hirsch, Bradford R; Carbone, David P; Schulman, Kevin A; Catchpole, Paul; Taylor, David; Geissler, Jan; Brinker, Nancy G; Meltzer, David; Kerr, David; Aapro, Matti

    2011-09-01

    The burden of cancer is growing, and the disease is becoming a major economic expenditure for all developed countries. In 2008, the worldwide cost of cancer due to premature death and disability (not including direct medical costs) was estimated to be US$895 billion. This is not simply due to an increase in absolute numbers, but also the rate of increase of expenditure on cancer. What are the drivers and solutions to the so-called cancer-cost curve in developed countries? How are we going to afford to deliver high quality and equitable care? Here, expert opinion from health-care professionals, policy makers, and cancer survivors has been gathered to address the barriers and solutions to delivering affordable cancer care. Although many of the drivers and themes are specific to a particular field-eg, the huge development costs for cancer medicines-there is strong concordance running through each contribution. Several drivers of cost, such as over-use, rapid expansion, and shortening life cycles of cancer technologies (such as medicines and imaging modalities), and the lack of suitable clinical research and integrated health economic studies, have converged with more defensive medical practice, a less informed regulatory system, a lack of evidence-based sociopolitical debate, and a declining degree of fairness for all patients with cancer. Urgent solutions range from re-engineering of the macroeconomic basis of cancer costs (eg, value-based approaches to bend the cost curve and allow cost-saving technologies), greater education of policy makers, and an informed and transparent regulatory system. A radical shift in cancer policy is also required. Political toleration of unfairness in access to affordable cancer treatment is unacceptable. The cancer profession and industry should take responsibility and not accept a substandard evidence base and an ethos of very small benefit at whatever cost; rather, we need delivery of fair prices and real value from new technologies

  15. A Bootstrap Approach to an Affordable Exploration Program

    NASA Technical Reports Server (NTRS)

    Oeftering, Richard C.

    2011-01-01

    This paper examines the potential to build an affordable sustainable exploration program by adopting an approach that requires investing in technologies that can be used to build a space infrastructure from very modest initial capabilities. Human exploration has had a history of flight programs that have high development and operational costs. Since Apollo, human exploration has had very constrained budgets and they are expected be constrained in the future. Due to their high operations costs it becomes necessary to consider retiring established space facilities in order to move on to the next exploration challenge. This practice may save cost in the near term but it does so by sacrificing part of the program s future architecture. Human exploration also has a history of sacrificing fully functional flight hardware to achieve mission objectives. An affordable exploration program cannot be built when it involves billions of dollars of discarded space flight hardware, instead, the program must emphasize preserving its high value space assets and building a suitable permanent infrastructure. Further this infrastructure must reduce operational and logistics cost. The paper examines the importance of achieving a high level of logistics independence by minimizing resource consumption, minimizing the dependency on external logistics, and maximizing the utility of resources available. The approach involves the development and deployment of a core suite of technologies that have minimum initial needs yet are able expand upon initial capability in an incremental bootstrap fashion. The bootstrap approach incrementally creates an infrastructure that grows and becomes self sustaining and eventually begins producing the energy, products and consumable propellants that support human exploration. The bootstrap technologies involve new methods of delivering and manipulating energy and materials. These technologies will exploit the space environment, minimize dependencies, and

  16. Plastic modes of listening: affordance in constructed sound environments

    NASA Astrophysics Data System (ADS)

    Sjolin, Anders

    This thesis is concerned with how the ecological approach to perception with the inclusion of listening modes, informs the creation of sound art installation, or more specifically as referred to in this thesis as constructed sound environments. The basis for the thesis has been a practiced based research where the aim and purpose of the written part of this PhD project has been to critically investigate the area of sound art, in order to map various approaches towards participating in and listening to a constructed sound environment. The main areas has been the notion of affordance as coined by James J. Gibson (1986), listening modes as coined by Pierre Schaeffer (1966) and further developed by Michel Chion (1994), aural architects as coined by Blesser and Salter (2007) and the holistic approach towards understanding sound art developed by Brandon LaBelle (2006). The findings within the written part of the thesis, based on a qualitative analysis, have informed the practice that has resulted in artefacts in the form of seven constructed sound environments that also functions as case studies for further analysis. The aim of the practice has been to exemplify the methodology, strategy and progress behind the organisation and construction of sound environments The research concerns point towards the acknowledgment of affordance as the crucial factor in understanding a constructed sound environment. The affordance approach govern the idea that perceiving a sound environment is a top-down process where the autonomic quality of a constructed sound environment is based upon the perception of structures of the sound material and its relationship with speaker placement and surrounding space. This enables a researcher to side step the conflicting poles of musical/abstract and non-musical/realistic classification of sound elements and regard these poles as included, not separated elements in the analysis of a constructed sound environment.

  17. DOE-HUD Initiative: Making Housing Affordable Through Energy Efficiency

    SciTech Connect

    Not Available

    1991-10-01

    A new collaborative program of the U.S. Department of Energy (DOE) and the U.S. Department of Housing and Urban Development (HUD) is a significant step toward making HUD-aided housing more comfortable and affordable through greater energy efficiency. The initiative on Energy Efficiency in Housing combines DOE's technical capabilities and HUD's experience in housing assistance. Over the next decade, the energy savings potential of this initiative is estimated to be 150 trillion Btu (0.15 quad) per year, or nearly $1.5 billion in annual energy costs.

  18. New affordable options for infrastructure and asset protection

    SciTech Connect

    2009-09-15

    Securitas is one of the leaders evolving with technology and delivering new forms of affordable security for mining facilities. It was called in to protect a large mothballed coal mine in the central USA, the victim of repeated thefts. First, Mobile Surveillance Units (MSUs) were installed but thefts continued. Later, a new wireless video security system called Videofied which used MotionViewers which use infrared detectors to detect movement and send a 10 second clip of the intrusion to an operator. This led to the thieves being caught. 2 photos.

  19. Affordable care 2014: a tale of two boards.

    PubMed

    Hirsch, Joshua A; Barr, Robert M; McGinty, Geraldine; Nicola, Gregory N; Schaefer, Pamela W; Silva, Ezequiel; Manchikanti, Laxmaiah

    2014-11-01

    The Patient Protection and Affordable Care Act (ACA) became law on 23 March 2010. As part of the law, two independent boards were established. The Patient-Centered Outcomes Research Institute embodies national aspirations for employing comparative effectiveness research in healthcare decision-making, and the Independent Payment Advisory Board is focused on the need for a group of impartial experts to establish anticipatable growth rates for Medicare. Approximately 4 years after the bill was passed into law, these independent boards are at very different points in their life cycles. This article provides a status update. PMID:24962452

  20. Enabling Dedicated, Affordable Space Access Through Aggressive Technology Maturation

    NASA Technical Reports Server (NTRS)

    Jones, Jonathan E.; Kibbey, Timothy P.; Cobb, C. Brent; Harris, Lawanna L.

    2014-01-01

    A launch vehicle at the scale and price point which allows developers to take reasonable risks with high payoff propulsion and avionics hardware solutions does not exist today. Establishing this service provides a ride through the proverbial technology "valley of death" that lies between demonstration in laboratory and flight environments. NASA's NanoLaunch effort will provide the framework to mature both earth-to-orbit and on-orbit propulsion and avionics technologies while also providing affordable, dedicated access to low earth orbit for cubesat class payloads.

  1. The Affordable Care Act versus Medicare for All.

    PubMed

    Seidman, Laurence

    2015-08-01

    Many problems facing the Affordable Care Act would disappear if the nation were instead implementing Medicare for All - the extension of Medicare to every age group. Every American would be automatically covered for life. Premiums would be replaced with a set of Medicare taxes. There would be no patient cost sharing. Individuals would have free choice of doctors. Medicare's single-payer bargaining power would slow price increases and reduce medical cost as a percentage of gross domestic product (GDP). Taxes as a percentage of GDP would rise from below average to average for economically advanced nations. Medicare for All would be phased in by age. PMID:26124300

  2. Creating affordable Internet map server applications for regional scale applications.

    PubMed

    Lembo, Arthur J; Wagenet, Linda P; Schusler, Tania; DeGloria, Stephen D

    2007-12-01

    This paper presents an overview and process for developing an Internet Map Server (IMS) application for a local volunteer watershed group using an Internal Internet Map Server (IIMS) strategy. The paper illustrates that modern GIS architectures utilizing an internal Internet map server coupled with a spatial SQL command language allow for rapid development of IMS applications. The implication of this approach means that powerful IMS applications can be rapidly and affordably developed for volunteer organizations that lack significant funds or a full time information technology staff. PMID:17234328

  3. 75 FR 81662 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Affordable...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-28

    ...; Affordable Care Act Advance Notice of Rescission ACTION: Notice. SUMMARY: The Department of Labor (DOL... information collection request (ICR) titled, ``Affordable Care Act Advance Notice of Rescission,'' to the..._PRA_PUBLIC@dol.gov . SUPPLEMENTARY INFORMATION: The Patient Protection and Affordable Care Act...

  4. 77 FR 31513 - Patient Protection and Affordable Care Act; Establishment of Exchanges and Qualified Health Plans...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-29

    ... HUMAN SERVICES 45 CFR Parts 155, 156, and 157 RIN 0938-AQ67 Patient Protection and Affordable Care Act... Federal Register on March 27, 2012, entitled ``Patient Protection and Affordable Care Act; Establishment... rule regarding the codification of section 1413(c) of the Affordable Care Act. To align the...

  5. 75 FR 81662 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Affordable...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-28

    ...; Affordable Care Act Patient Protection Notice ACTION: Notice. SUMMARY: The Department of Labor (DOL) hereby... collection request (ICR) titled, ``Affordable Care Act Patient Protection Notice,'' to the Office of... Security Administration (EBSA). Title of Collection: Affordable Care Act Patient Protection Notice....

  6. 77 FR 26046 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Affordable...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-02

    ...; Affordable Care Act Internal Claims and Appeals and External Review Procedures for Non-Grandfathered Plans... Administration (EBSA) sponsored information collection request (ICR) titled, ``Affordable Care Act Internal...: Affordable Care Act Internal Claims and Appeals and External Review Procedures for Non-grandfathered...

  7. 76 FR 11283 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Affordable...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-01

    ...; Affordable Care Act Internal Claims and Appeals and External Review Procedures for Non-Grandfathered Plans... Administration (EBSA) sponsored information collection request (ICR) titled, ``Affordable Care Act Internal... Affordable Care Act added Public Health Service Act section 2719, which provides rules relating to......

  8. 77 FR 17143 - Medicaid Program; Eligiblity Changes Under the Affordable Care Act of 2010

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-23

    ... Medicaid eligibility changes under the Affordable Care Act (listed in more detail in 76 FR 51155) and... Services 42 CFR Parts 431, 435 and 457 Medicaid Program; Eligibility Changes Under the Affordable Care Act... Parts 431, 435, and 457 RIN 0938-AQ62 Medicaid Program; Eligiblity Changes Under the Affordable Care...

  9. 77 FR 70643 - Patient Protection and Affordable Care Act; Standards Related to Essential Health Benefits...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-26

    ... Protection and Affordable Care Act; Standards Related to Essential Health Benefits, Actuarial Value, and... Patient Protection and Affordable Care Act; Standards Related to Essential Health Benefits, Actuarial... Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation...

  10. Learning Outcomes Afforded by Self-Assessed, Segmented Video-Print Combinations

    ERIC Educational Resources Information Center

    Koumi, Jack

    2015-01-01

    Learning affordances of video and print are examined in order to assess the learning outcomes afforded by hybrid video-print learning packages. The affordances discussed for print are: navigability, surveyability and legibility. Those discussed for video are: design for constructive reflection, provision of realistic experiences, presentational…

  11. Teacher Perceptions of Learning Affordances of Multi-User Virtual Environments

    ERIC Educational Resources Information Center

    Gamage, Vimani; Tretiakov, Alexei; Crump, Barbara

    2011-01-01

    While the affordances of multi-user virtual environments (MUVEs) for teaching and learning are a subject of numerous experience reports, there is little research on educators' perceptions of various MUVE affordances claimed in the literature. We investigate the educators' perceptions of claimed MUVE affordances for learning by conducting in-depth…

  12. 76 FR 59702 - Notice of Intent To Award Affordable Care Act (ACA) Funding

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-27

    ... HUMAN SERVICES Centers for Disease Control and Prevention Notice of Intent To Award Affordable Care Act... Services (HHS). ACTION: Notice. Overview Information Notice of Intent to Award Affordable Care Act (ACA...: This notice provides public announcement of CDC's intent to award Affordable Care Act...

  13. Collective cell traction force analysis on aligned smooth muscle cell sheet between three-dimensional microwalls

    PubMed Central

    Zhang, Ying; Ng, Soon Seng; Wang, Yilei; Feng, Huixing; Chen, Wei Ning; Chan-Park, Mary B.; Li, Chuan; Chan, Vincent

    2014-01-01

    During the past two decades, novel biomaterial scaffold for cell attachment and culture has been developed for applications in tissue engineering, biosensing and regeneration medicine. Tissue engineering of blood vessels remains a challenge owing to the complex three-layer histology involved. In order to engineer functional blood vessels, it is essential to recapitulate the characteristics of vascular smooth muscle cells (SMCs) inside the tunica media, which is known to be critical for vasoconstriction and vasodilation of the circulatory system. Until now, there has been a lack of understanding on the mechanotransduction of the SMC layer during the transformation from viable synthetic to quiescent contractile phenotypes. In this study, microfabricated arrays of discontinuous microwalls coated with fluorescence microbeads were developed to probe the mechanotransduction of the SMC layer. First, the system was exploited for stimulating the formation of a highly aligned orientation of SMCs in native tunica medium. Second, atomic force microscopy in combination with regression analysis was applied to measure the elastic modulus of a polyacrylamide gel layer coated on the discontinuous microwall arrays. Third, the conventional traction force assay for single cell measurement was extended for applications in three-dimensional cell aggregates. Then, the biophysical effects of discontinuous microwalls on the mechanotransduction of the SMC layer undergoing cell alignment were probed. Generally, the cooperative multiple cell–cell and cell–microwall interactions were accessed quantitatively by the newly developed assay with the aid of finite-element modelling. The results show that the traction forces of highly aligned cells lying in the middle region between two opposing microwalls were significantly lower than those lying adjacent to the microwalls. Moreover, the spatial distributions of Von Mises stress during the cell alignment process were dependent on the collective

  14. Re-adhesion control for a railway single wheelset test rig based on the behaviour of the traction motor

    NASA Astrophysics Data System (ADS)

    Zhao, Y.; Liang, B.

    2013-08-01

    A method for detecting wheel slip/slide and re-adhesion control of AC traction motors in railway applications is presented in this paper. This enables a better utilisation of available adhesion and could also reduce wheel wear by reducing high creep values. With this method, the wheel-rail (roller) creepage, creep force and friction coefficient can be indirectly detected and estimated by measuring the voltage, current and speed of the AC traction motor and using an extended Kalman filter. The re-adhesion controller is designed to regulate the motor torque command according to the maximum available adhesion based on the estimated results. Simulations under different friction coefficients are carried out to test the proposed method.

  15. On the Formulation of Weakly Singular Displacement/Traction Integral Equations; and Their Solution by the MLPG Method

    NASA Technical Reports Server (NTRS)

    Atluri, Satya N.; Shen, Shengping

    2002-01-01

    In this paper, a very simple method is used to derive the weakly singular traction boundary integral equation based on the integral relationships for displacement gradients. The concept of the MLPG method is employed to solve the integral equations, especially those arising in solid mechanics. A moving Least Squares (MLS) interpolation is selected to approximate the trial functions in this paper. Five boundary integral Solution methods are introduced: direct solution method; displacement boundary-value problem; traction boundary-value problem; mixed boundary-value problem; and boundary variational principle. Based on the local weak form of the BIE, four different nodal-based local test functions are selected, leading to four different MLPG methods for each BIE solution method. These methods combine the advantages of the MLPG method and the boundary element method.

  16. Performance Comparison between a Permanent Magnet Synchronous Motor and an Induction Motor as a Traction Motor for High Speed Train

    NASA Astrophysics Data System (ADS)

    Kondo, Minoru; Kawamura, Junya; Terauchi, Nobuo

    Performance tests are carried out to demonstrate the superiority of a permanent magnet synchronous motor to an induction motor as a traction motor for high-speed train. A prototype motor was manufactured by replacing the rotor of a conventional induction motor. The test results show that the permanent magnet motor is lighter, efficient and more silent than the induction motor because of the different rotor structure.

  17. Experimental Study on a Voltage Source Inverter-fed Induction Motor Traction System Connected to Fuel Cell

    NASA Astrophysics Data System (ADS)

    Furuya, Takemasa; Kondo, Keiichiro; Yamamoto, Takamitsu

    This paper describes the experimental results of a test to drive two induction motors through a VVVF inverter by 25kW class proton membrane type fuel cells (PEMFCs). The experiments are aimed at verifying the compatibility between the drive system for the railway vehicle traction and FCs. This paper describes test results of powering, powering-off procedure, and simulated slip-readhesion control test, respectively. Through the experiments, we obtained useful knowledge required in designing the fuel cell drive system.

  18. Lumbar extension exercises in conjunction with mechanical traction for the management of a patient with a lumbar herniated disc.

    PubMed

    Gagne, Allison R; Hasson, Scott M

    2010-05-01

    Low back pain resulting from lumbar disc herniation is a common reason for referral for physical therapy. There is no evidence to support the management of lumbar disc herniation and derangement using mechanical traction combined with lumbar extension exercises. Therefore, the purpose of this case report was to describe and discuss the use of mechanical traction in conjunction with lumbar extension exercises for a patient with a lumbar herniated disc. The patient was a 49-year-old male referred to physical therapy with a medical diagnosis of a lumbar herniated disc at L5-S1 with compression of the L5 nerve root confirmed by MRI. The patient's chief complaint was pain over the left lumbosacral and central lumbar region with radiating pain into the left buttock accompanied by numbness and tingling in the left lower leg and foot. The patient was seen for a total of 14 visits. The first 5 days (2 weeks) of therapy consisted of lumbar extension exercises. For the following nine visits (over a 3-week period), mechanical traction was added as an adjunct to the extension exercises. Outcome measures included the Oswestry Disability Questionnaire, Back Pain Function Scale (BPFS), and the Numeric Pain Rating Scale (NPRS). Results from initial evaluation to discharge (Oswestry: 36% to 0%; BPFS: 33/60 to 57/60; NPRS: 7/10 to 0/10) demonstrated that the patient no longer experienced low back pain and improved in terms of functional status and pain-related disability. The patient no longer complained of numbness and tingling in the left lower extremity and the goals for the patient had been attained. The data from this case report suggests lumbar extension exercises in conjunction with mechanical traction facilitated the patient's improvement in pain and return to prior level of function. PMID:20397860

  19. Anticipating Human Activities Using Object Affordances for Reactive Robotic Response.

    PubMed

    Koppula, Hema S; Saxena, Ashutosh

    2016-01-01

    An important aspect of human perception is anticipation, which we use extensively in our day-to-day activities when interacting with other humans as well as with our surroundings. Anticipating which activities will a human do next (and how) can enable an assistive robot to plan ahead for reactive responses. Furthermore, anticipation can even improve the detection accuracy of past activities. The challenge, however, is two-fold: We need to capture the rich context for modeling the activities and object affordances, and we need to anticipate the distribution over a large space of future human activities. In this work, we represent each possible future using an anticipatory temporal conditional random field (ATCRF) that models the rich spatial-temporal relations through object affordances. We then consider each ATCRF as a particle and represent the distribution over the potential futures using a set of particles. In extensive evaluation on CAD-120 human activity RGB-D dataset, we first show that anticipation improves the state-of-the-art detection results. We then show that for new subjects (not seen in the training set), we obtain an activity anticipation accuracy (defined as whether one of top three predictions actually happened) of 84.1, 74.4 and 62.2 percent for an anticipation time of 1, 3 and 10 seconds respectively. Finally, we also show a robot using our algorithm for performing a few reactive responses. PMID:26656575

  20. Methadone dosing, heroin affordability, and the severity of addiction.

    PubMed Central

    Bach, P B; Lantos, J

    1999-01-01

    OBJECTIVES: This study sought to track changes in US heroin prices from 1988 to 1995 and to determine whether changes in the affordability of heroin were associated with changes in the use of heroin by users seeking methadone treatment, as indexed by methadone dose levels. METHODS: Data on the price of heroin were from the Drug Enforcement Administration; data on methadone doses were from surveys conducted in 1988, 1990, and 1995 of 100 methadone maintenance centers. Multivariable models that controlled for time and city effects were used to ascertain whether clinics in cities where heroin was less expensive had patients receiving higher doses of methadone, which would suggest that these patients had relatively higher physiological levels of opiate addiction owing to increased heroin use. RESULTS: The amount of pure heroin contained in a $100 (US) purchase has increased on average 3-fold between 1988 and 1995. The average dose of methadone in clinics was positively associated with the affordability of local heroin (P < .01). CONCLUSIONS: When heroin prices fall, heroin addicts require more methadone (a heroin substitute) to stabilize their addiction--evidence that they are consuming more heroin. PMID:10224975