Science.gov

Sample records for major control point

  1. Galactosyltransferase 4 is a major control point for glycan branching in N-linked glycosylation

    PubMed Central

    McDonald, Andrew G.; Hayes, Jerrard M.; Bezak, Tania; Głuchowska, Sonia A.; Cosgrave, Eoin F. J.; Struwe, Weston B.; Stroop, Corné J. M.; Kok, Han; van de Laar, Teun; Rudd, Pauline M.; Tipton, Keith F.; Davey, Gavin P.

    2014-01-01

    ABSTRACT Protein N-glycosylation is a common post-translational modification that produces a complex array of branched glycan structures. The levels of branching, or antennarity, give rise to differential biological activities for single glycoproteins. However, the precise mechanism controlling the glycan branching and glycosylation network is unknown. Here, we constructed quantitative mathematical models of N-linked glycosylation that predicted new control points for glycan branching. Galactosyltransferase, which acts on N-acetylglucosamine residues, was unexpectedly found to control metabolic flux through the glycosylation pathway and the level of final antennarity of nascent protein produced in the Golgi network. To further investigate the biological consequences of glycan branching in nascent proteins, we glycoengineered a series of mammalian cells overexpressing human chorionic gonadotropin (hCG). We identified a mechanism in which galactosyltransferase 4 isoform regulated N-glycan branching on the nascent protein, subsequently controlling biological activity in an in vivo model of hCG activity. We found that galactosyltransferase 4 is a major control point for glycan branching decisions taken in the Golgi of the cell, which might ultimately control the biological activity of nascent glycoprotein. PMID:25271059

  2. ACCESS Pointing Control System

    NASA Technical Reports Server (NTRS)

    Brugarolas, Paul; Alexander, James; Trauger, John; Moody, Dwight; Egerman, Robert; Vallone, Phillip; Elias, Jason; Hejal, Reem; Camelo, Vanessa; Bronowicki, Allen; O'Connor, David; Partrick, Richard; Orzechowski, Pawel; Spitter, Connie; Lillie, Chuck

    2010-01-01

    ACCESS (Actively-Corrected Coronograph for Exoplanet System Studies) was one of four medium-class exoplanet concepts selected for the NASA Astrophysics Strategic Mission Concept Study (ASMCS) program in 2008/2009. The ACCESS study evaluated four major coronograph concepts under a common space observatory. This paper describes the high precision pointing control system (PCS) baselined for this observatory.

  3. SPS antenna pointing control

    NASA Technical Reports Server (NTRS)

    Hung, J. C.

    1980-01-01

    The pointing control of a microwave antenna of the Satellite Power System was investigated emphasizing: (1) the SPS antenna pointing error sensing method; (2) a rigid body pointing control design; and (3) approaches for modeling the flexible body characteristics of the solar collector. Accuracy requirements for the antenna pointing control consist of a mechanical pointing control accuracy of three arc-minutes and an electronic phased array pointing accuracy of three arc-seconds. Results based on the factors considered in current analysis, show that the three arc-minute overall pointing control accuracy can be achieved in practice.

  4. Does point of care prothrombin time measurement reduce the transfusion of fresh frozen plasma in patients undergoing major surgery? The POC-OP randomized-controlled trial

    PubMed Central

    2009-01-01

    Background Bleeding is a frequent complication during surgery. The intraoperative administration of blood products, including packed red blood cells, platelets and fresh frozen plasma (FFP), is often live saving. Complications of blood transfusions contribute considerably to perioperative costs and blood product resources are limited. Consequently, strategies to optimize the decision to transfuse are needed. Bleeding during surgery is a dynamic process and may result in major blood loss and coagulopathy due to dilution and consumption. The indication for transfusion should be based on reliable coagulation studies. While hemoglobin levels and platelet counts are available within 15 minutes, standard coagulation studies require one hour. Therefore, the decision to administer FFP has to be made in the absence of any data. Point of care testing of prothrombin time ensures that one major parameter of coagulation is available in the operation theatre within minutes. It is fast, easy to perform, inexpensive and may enable physicians to rationally determine the need for FFP. Methods/Design The objective of the POC-OP trial is to determine the effectiveness of point of care prothrombin time testing to reduce the administration of FFP. It is a patient and assessor blind, single center randomized controlled parallel group trial in 220 patients aged between 18 and 90 years undergoing major surgery (any type, except cardiac surgery and liver transplantation) with an estimated blood loss during surgery exceeding 20% of the calculated total blood volume or a requirement of FFP according to the judgment of the physicians in charge. Patients are randomized to usual care plus point of care prothrombin time testing or usual care alone without point of care testing. The primary outcome is the relative risk to receive any FFP perioperatively. The inclusion of 110 patients per group will yield more than 80% power to detect a clinically relevant relative risk of 0.60 to receive FFP of

  5. Pointing control for LDR

    NASA Technical Reports Server (NTRS)

    Yam, Y.; Briggs, C.

    1988-01-01

    One important aspect of the LDR control problem is the possible excitations of structural modes due to random disturbances, mirror chopping, and slewing maneuvers. An analysis was performed to yield a first order estimate of the effects of such dynamic excitations. The analysis involved a study of slewing jitters, chopping jitters, disturbance responses, and pointing errors, making use of a simplified planar LDR model which describes the LDR dynamics on a plane perpendicular to the primary reflector. Briefly, the results indicate that the command slewing profile plays an important role in minimizing the resultant jitter, even to a level acceptable without any control action. An optimal profile should therefore be studied.

  6. Wavefront sensing, control, and pointing

    NASA Technical Reports Server (NTRS)

    Pitts, Thomas; Sevaston, George; Agronin, Michael; Bely, Pierre; Colavita, Mark; Clampin, Mark; Harvey, James; Idell, Paul; Sandler, Dave; Ulmer, Melville

    1992-01-01

    A majority of future NASA astrophysics missions from orbiting interferometers to 16-m telescopes on the Moon have, as a common requirement, the need to bring light from a large entrance aperture to the focal plane in a way that preserves the spatial coherence properties of the starlight. Only by preserving the phase of the incoming wavefront, can many scientific observations be made, observations that range from measuring the red shift of quasi-stellar objects (QSO's) to detecting the IR emission of a planet in orbit around another star. New technologies for wavefront sensing, control, and pointing hold the key to advancing our observatories of the future from those already launched or currently under development. As the size of the optical system increases, either to increase the sensitivity or angular resolution of the instrument, traditional technologies for maintaining optical wavefront accuracy become prohibitively expensive or completely impractical. For space-based instruments, the low mass requirement and the large temperature excursions further challenge existing technologies. The Hubble Space Telescope (HST) is probably the last large space telescope to rely on passive means to keep its primary optics stable and the optical system aligned. One needs only look to the significant developments in wavefront sensing, control, and pointing that have occurred over the past several years to appreciate the potential of this technology for transforming the capability of future space observatories. Future developments in space-borne telescopes will be based in part on developments in ground-based systems. Telescopes with rigid primary mirrors much larger than 5 m in diameter are impractical because of gravity loading. New technologies are now being introduced, such as active optics, that address the scale problem and that allow very large telescopes to be built. One approach is a segmented design such as that being pioneered by the W.M. Keck telescope now under

  7. 47 CFR 80.41 - Control points and dispatch points.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Control points and dispatch points. 80.41... SERVICES STATIONS IN THE MARITIME SERVICES Applications and Licenses § 80.41 Control points and dispatch... dispatch points may be installed and used without obtaining any authorization from the Commission....

  8. 47 CFR 80.41 - Control points and dispatch points.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Control points and dispatch points. 80.41... SERVICES STATIONS IN THE MARITIME SERVICES Applications and Licenses § 80.41 Control points and dispatch... dispatch points may be installed and used without obtaining any authorization from the Commission....

  9. 47 CFR 80.41 - Control points and dispatch points.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Control points and dispatch points. 80.41... SERVICES STATIONS IN THE MARITIME SERVICES Applications and Licenses § 80.41 Control points and dispatch... dispatch points may be installed and used without obtaining any authorization from the Commission....

  10. 47 CFR 80.41 - Control points and dispatch points.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Control points and dispatch points. 80.41... SERVICES STATIONS IN THE MARITIME SERVICES Applications and Licenses § 80.41 Control points and dispatch... dispatch points may be installed and used without obtaining any authorization from the Commission....

  11. 47 CFR 80.41 - Control points and dispatch points.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Control points and dispatch points. 80.41... SERVICES STATIONS IN THE MARITIME SERVICES Applications and Licenses § 80.41 Control points and dispatch... dispatch points may be installed and used without obtaining any authorization from the Commission....

  12. 36 CFR 907.6 - Major decision points.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... decisionmaking process. For most Corporation projects there are three distinct stages in the decision making...) Implementation stage. (b) Environmental review will be integrated into the decision making process of the... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Major decision points....

  13. 36 CFR 1010.5 - Major decision points.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-making process. Most Trust projects have three distinct stages in the decision-making process: (1... stage. (b) Environmental review will be integrated into the decision-making process of the Trust as... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Major decision points....

  14. 36 CFR 907.6 - Major decision points.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... decisionmaking process. For most Corporation projects there are three distinct stages in the decision making...) Implementation stage. (b) Environmental review will be integrated into the decision making process of the... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Major decision points....

  15. 36 CFR 907.6 - Major decision points.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... decisionmaking process. For most Corporation projects there are three distinct stages in the decision making...) Implementation stage. (b) Environmental review will be integrated into the decision making process of the... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Major decision points....

  16. 36 CFR 907.6 - Major decision points.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... decisionmaking process. For most Corporation projects there are three distinct stages in the decision making...) Implementation stage. (b) Environmental review will be integrated into the decision making process of the... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Major decision points....

  17. 36 CFR 1010.5 - Major decision points.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-making process. Most Trust projects have three distinct stages in the decision-making process: (1... stage. (b) Environmental review will be integrated into the decision-making process of the Trust as... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Major decision points....

  18. 14 CFR 1216.304 - Major decision points.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 5 2012-01-01 2012-01-01 false Major decision points. 1216.304 Section 1216.304 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION ENVIRONMENTAL QUALITY... facility projects, generally have four distinct phases: The conceptual study phase; the detailed...

  19. Control of precision pointing system

    NASA Astrophysics Data System (ADS)

    Gu, Zheng

    Distributed-parameter modeling of tube with moving mass using Magnetic Compressional Damping Treatment (MCDT) is developed. Hamilton's principle is utilized to develop the model and boundary condition of a tube with moving mass using MCDT. Based on the electromagnetic theory, the relation between the generated magnet force of the actuator (MCDT) and the control current is determined. A stable control strategy is developed to damp out the vibration of the tube with moving mass using MCDT system. The fundamental characteristics of an active and a passive version of the Magnetic Compressional Damping Treatment (MCDT) are investigated by the finite element method. The damping characteristics of tube/MCDT system are modeled by Golla-Hughes-McTavish (GHM) method in order to predict the tube response in the time domain. The numerical results are verified through experimentation using a cantilevered tube treated with MCDT at the free end. The tube vibration due to an internally moving load is controlled by the MCDT using a deflection feedback controller. Close agreement is obtained between theory and experiments. The effectiveness of the MCDT in attenuating structural vibration of the tube has also been clearly demonstrated in the time and frequency domains. The developed theoretical and experimental techniques present invaluable tools for designing and predicting the performance of precision pointing tubes different damping treatments when subjected to moving loads.

  20. Satellite Power System (SPS) antenna pointing control

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Accuracy requirements for the SPS antenna pointing control consists of a mechanical pointing accuracy of three arc minutes and an electronic phased array pointing accuracy of three arc seconds. Results of this study, based on the factors considered in current analysis, show that the three arc minute overall pointing control accuracy can be achieved for the SPS in practice.

  1. A low cost LST pointing control system

    NASA Technical Reports Server (NTRS)

    Glaese, J. R.; Kennel, H. F.; Nurre, G. S.; Seltzer, S. M.; Shelton, H. L.

    1975-01-01

    Vigorous efforts to reduce costs, coupled with changes in LST guidelines, took place in the Fall of 1974. These events made a new design of the LST and its Pointing and Attitude Control System possible. The major design changes are summarized as: an annular Support Systems Module; removal of image motion compensation; reaction wheels instead of CMG's; a magnetic torquer system to also perform the emergency and backup functions, eliminating the previously required mass expulsion system. Preliminary analysis indicates the Low Cost LST concept can meet the newly defined requirements and results in a significantly reduced development cost.

  2. 47 CFR 22.325 - Control points.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Control points. 22.325 Section 22.325... Operational and Technical Requirements Operational Requirements § 22.325 Control points. Each station in the Public Mobile Services must have at least one control point and a person on duty who is responsible...

  3. 47 CFR 22.325 - Control points.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Control points. 22.325 Section 22.325... Operational and Technical Requirements Operational Requirements § 22.325 Control points. Each station in the Public Mobile Services must have at least one control point and a person on duty who is responsible...

  4. 47 CFR 22.325 - Control points.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Control points. 22.325 Section 22.325... Operational and Technical Requirements Operational Requirements § 22.325 Control points. Each station in the Public Mobile Services must have at least one control point and a person on duty who is responsible...

  5. 47 CFR 22.325 - Control points.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Control points. 22.325 Section 22.325... Operational and Technical Requirements Operational Requirements § 22.325 Control points. Each station in the Public Mobile Services must have at least one control point and a person on duty who is responsible...

  6. 47 CFR 22.325 - Control points.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Control points. 22.325 Section 22.325... Operational and Technical Requirements Operational Requirements § 22.325 Control points. Each station in the Public Mobile Services must have at least one control point and a person on duty who is responsible...

  7. Pointing control for the International Comet Mission

    NASA Technical Reports Server (NTRS)

    Leblanc, D. R.; Schumacher, L. L.

    1980-01-01

    The design of the pointing control system for the proposed International Comet Mission, intended to fly by Comet Halley and rendezvous with Comet Tempel-2 is presented. Following a review of mission objectives and the spacecraft configuration, design constraints on the pointing control system controlling the two-axis gimballed scan platform supporting the science instruments are discussed in relation to the scientific requirements of the mission. The primary design options considered for the pointing control system design for the baseline spacecraft are summarized, and the design selected, which employs a target-referenced, inertially stabilized control system, is described in detail. The four basic modes of operation of the pointing control subsystem (target acquisition, inertial hold, target track and slew) are discussed as they relate to operations at Halley and Tempel-2. It is pointed that the pointing control system design represents a significant advance in the state of the art of pointing controls for planetary missions.

  8. Spacecraft Pointing and Position Control,

    DTIC Science & Technology

    1981-11-01

    Control Loop Electronics R. Rotor D. Transverse Oscillation Damper S. Stator E. Motor V. Clamping mechanism Fig.1 M 2-3 3.2 Torques applied to the...However, with the presence of a passive nutation damper and an onboard wobble control algorithm, nutation and wobble can be assumed negligible during...with a damper having a time constant chosen to provide overall stability. The power of such satellites i. limited by the size of the fixedf solar

  9. 36 CFR 1010.5 - Major decision points.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Trust Area must be considered along with technical, financial, and other factors throughout the decision... earliest point at which meaningful analysis can be developed for the proposed action or project and...

  10. 36 CFR 1010.5 - Major decision points.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Trust Area must be considered along with technical, financial, and other factors throughout the decision... earliest point at which meaningful analysis can be developed for the proposed action or project and...

  11. 36 CFR 1010.5 - Major decision points.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... decision points. (a) The possible environmental effects of a proposed action or project within the Presidio...-making process. Most Trust projects have three distinct stages in the decision-making process: (1) Conceptual or preliminary study stage; (2) Detailed planning or final decision stage; (3)...

  12. 14 CFR 1216.304 - Major decision points.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the National Environmental Policy Act of 1969. Major NASA activities, particularly R&D (or SFCDC) and.../definition phase; the development/construction phase; and the operation phase. (Other NASA activities have... determination as to whether an environmental impact statement is required must be made prior to the decision...

  13. Optimal control problems with switching points

    NASA Astrophysics Data System (ADS)

    Seywald, Hans

    1991-09-01

    An overview is presented of the problems and difficulties that arise in solving optimal control problems with switching points. A brief discussion of existing optimality conditions is given and a numerical approach for solving the multipoint boundary value problems associated with the first-order necessary conditions of optimal control is presented. Two real-life aerospace optimization problems are treated explicitly. These are altitude maximization for a sounding rocket (Goddard Problem) in the presence of a dynamic pressure limit, and range maximization for a supersonic aircraft flying in the vertical, also in the presence of a dynamic pressure limit. In the second problem singular control appears along arcs with active dynamic pressure limit, which in the context of optimal control, represents a first-order state inequality constraint. An extension of the Generalized Legendre-Clebsch Condition to the case of singular control along state/control constrained arcs is presented and is applied to the aircraft range maximization problem stated above. A contribution to the field of Jacobi Necessary Conditions is made by giving a new proof for the non-optimality of conjugate paths in the Accessory Minimum Problem. Because of its simple and explicit character, the new proof may provide the basis for an extension of Jacobi's Necessary Condition to the case of the trajectories with interior point constraints. Finally, the result that touch points cannot occur for first-order state inequality constraints is extended to the case of vector valued control functions.

  14. Space Telescope precision pointing control system

    NASA Technical Reports Server (NTRS)

    Beals, G. A.; Crum, R. C.; Dougherty, H. J.; Hegel, D. K.; Kelley, J. L.

    1986-01-01

    The Hubble Space Telescope has the most stringent pointing requirements imposed on any spacecraft to date. The overall HST stability shall not exceed 0.007 arc-seconds rms. The Pointing Control System utilizes fine guidance sensors and rate gyros for attitude reference and rate information. Control torques are provided by reaction wheels. A digital computer collects the sensor data, performs the control law computations, and sends torque commands to the reaction wheels. To attain this precision pointing, improvements were made to the rate gyros to lower their noise characteristics and to the reaction wheels to reduce their emitted vibration levels. The control system design was validated in a test sequence which progressed from model verification tests on an air-bearing to operations-oriented, closed loop testing on the assembled vehicle. A test system is described which allowed the simultaneous production of test case command loads for the flight computer and plots of predicted profiles to assist in test data analysis. Workarounds were required during system test to accommodate gyro biases and noise introduced into the closed loop system. Testing and analysis indicate that the HST will provide the capability to meet the requirements for precision pointing.

  15. Parachute suspended solar pointing control system

    NASA Astrophysics Data System (ADS)

    Sakoda, G. T.; Fujimoto, R. J.; Shigemoto, J. M.; Windsor, R. M.

    A high altitude parachute suspended solar pointing control system has been developed and flight tested for use in the altitude range of 30 to 70 kilometers. This development provides an opportunity for extended solar observations at altitudes higher than that attainable by helium balloons. The new system utilizes the NASA high altitude cross parachute to slow the descent of a rocket launched payload allowing observations in the region of interest. Solar pointing is established by using solar sensors in conjunction with a servo controlled platform and cold gas thrusters for payload roll control. The inherent spin of the cross parachute is decoupled by a swivel joint attached to the parachute suspension lines. This paper describes the design, test and flight performance of the new system.

  16. Parachute-suspended solar pointing control system

    NASA Astrophysics Data System (ADS)

    Sakoda, G. T.; Fujimoto, R. J.; Shigemoto, J. M.; Windsor, R. M.

    1984-04-01

    A high altitude parachute suspended solar pointing control system has been developed and flight tested for use in the altitude range of 30 to 70 kilometers. This development provides an opportunity for extended solar observations at altitudes higher than that attainable by helium balloons. The new system utilizes the NASA high altitude cross parachute to slow the descent of a rocket launched payload allowing observations in the region of interest. Solar pointing is established by using solar sensors in conjunction with a servo controlled platform and cold gas thrusters for payload roll control. The inherent spin of the cross parachute is decoupled by a swivel joint attached to the parachute suspension lines. This paper describes the design, test and flight performance of the new system.

  17. Remote temperature-set-point controller

    DOEpatents

    Burke, William F.; Winiecki, Alan L.

    1986-01-01

    An instrument for carrying out mechanical strain tests on metallic samples with the addition of an electrical system for varying the temperature with strain, the instrument including opposing arms and associated equipment for holding a sample and varying the mechanical strain on the sample through a plurality of cycles of increasing and decreasing strain within predetermined limits, circuitry for producing an output signal representative of the strain during the tests, apparatus including a set point and a coil about the sample for providing a controlled temperature in the sample, and circuitry interconnected between the strain output signal and set point for varying the temperature of the sample linearly with strain during the tests.

  18. Controlling superconductivity by tunable quantum critical points.

    PubMed

    Seo, S; Park, E; Bauer, E D; Ronning, F; Kim, J N; Shim, J-H; Thompson, J D; Park, Tuson

    2015-03-04

    The heavy fermion compound CeRhIn5 is a rare example where a quantum critical point, hidden by a dome of superconductivity, has been explicitly revealed and found to have a local nature. The lack of additional examples of local types of quantum critical points associated with superconductivity, however, has made it difficult to unravel the role of quantum fluctuations in forming Cooper pairs. Here, we show the precise control of superconductivity by tunable quantum critical points in CeRhIn5. Slight tin-substitution for indium in CeRhIn5 shifts its antiferromagnetic quantum critical point from 2.3 GPa to 1.3 GPa and induces a residual impurity scattering 300 times larger than that of pure CeRhIn5, which should be sufficient to preclude superconductivity. Nevertheless, superconductivity occurs at the quantum critical point of the tin-doped metal. These results underline that fluctuations from the antiferromagnetic quantum criticality promote unconventional superconductivity in CeRhIn5.

  19. Digital controller design: Analysis of the annular suspension pointing system

    NASA Technical Reports Server (NTRS)

    Kuo, B. C.

    1979-01-01

    The Annular Suspension and Pointing System (ASPS) is a payload auxiliary pointing device of the Space Shuttle. The ASPS is comprised of two major subassemblies, a vernier and a coarse pointing subsystem. The experiment is attached to a mounting plate/rim combination which is suspended on magnetic bearing/actuators (MBA) strategically located about the rim. Fine pointing is achieved by gimballing the plate/rim within the MBA gaps. Control about the experiment line-of-sight is obtained through the use of a non-contacting rim drive and positioning torquer. All sensors used to close the servo loops on the vernier system are noncontacting elements. Therefore, the experiment is a free-flyer constrained only by the magnetic forces generated by the control loops.

  20. Remote temperature-set-point controller

    DOEpatents

    Burke, W.F.; Winiecki, A.L.

    1984-10-17

    An instrument is described for carrying out mechanical strain tests on metallic samples with the addition of means for varying the temperature with strain. The instrument includes opposing arms and associated equipment for holding a sample and varying the mechanical strain on the sample through a plurality of cycles of increasing and decreasing strain within predetermined limits, circuitry for producing an output signal representative of the strain during the tests, apparatus including a a set point and a coil about the sample for providing a controlled temperature in the sample, and circuitry interconnected between the strain output signal and set point for varying the temperature of the sample linearly with strain during the tests.

  1. Catfish Point Control Structure: Foundation Investigation

    DTIC Science & Technology

    1948-01-01

    Averaf£e 63-88 75 20-27 23 43-62 51 SamJ1le Depth Elev !!!?.:.. Ft ~ Borins 1 - Gr.El. i 2.8 7 6.8- 7.8 -4.5 10 10.0-10.9 -7.6 13 13.1-13.9...I LEGEND @ ’ UNDISTURBED SAMPLE BORIN (; • GENERAL SAMPLE BORING .· A- 2 • - Grand Lake WATERWAYS EXPERIMENT SiAT’ON CATFISH POINT CONTROL

  2. 47 CFR 90.429 - Control point and dispatch point requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Control point and dispatch point requirements... and dispatch point requirements. (a) Control point required. Unless permitted to be operated on an... operation of the transmitter either to disconnect the dispatch point circuits from the transmitter or...

  3. 47 CFR 90.429 - Control point and dispatch point requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Control point and dispatch point requirements... and dispatch point requirements. (a) Control point required. Unless permitted to be operated on an... operation of the transmitter either to disconnect the dispatch point circuits from the transmitter or...

  4. 47 CFR 90.429 - Control point and dispatch point requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Control point and dispatch point requirements... and dispatch point requirements. (a) Control point required. Unless permitted to be operated on an... operation of the transmitter either to disconnect the dispatch point circuits from the transmitter or...

  5. 47 CFR 90.429 - Control point and dispatch point requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Control point and dispatch point requirements... and dispatch point requirements. (a) Control point required. Unless permitted to be operated on an... operation of the transmitter either to disconnect the dispatch point circuits from the transmitter or...

  6. 47 CFR 90.429 - Control point and dispatch point requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Control point and dispatch point requirements... and dispatch point requirements. (a) Control point required. Unless permitted to be operated on an... operation of the transmitter either to disconnect the dispatch point circuits from the transmitter or...

  7. 49 CFR 236.403 - Signals at controlled point.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Traffic Control Systems Standards § 236.403 Signals at controlled point. Signals at controlled point shall be...

  8. 49 CFR 236.403 - Signals at controlled point.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Traffic Control Systems Standards § 236.403 Signals at controlled point. Signals at controlled point shall be...

  9. Do Nondomestic Undergraduates Choose a Major Field in Order to Maximize Grade Point Averages?

    ERIC Educational Resources Information Center

    Bergman, Matthew E.; Fass-Holmes, Barry

    2016-01-01

    The authors investigated whether undergraduates attending an American West Coast public university who were not U.S. citizens (nondomestic) maximized their grade point averages (GPA) through their choice of major field. Multiple regression hierarchical linear modeling analyses showed that major field's effect size was small for these…

  10. 47 CFR 11.16 - National Control Point Procedures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false National Control Point Procedures. 11.16...) General § 11.16 National Control Point Procedures. The National Control Point Procedures are written instructions issued by the FCC to national level EAS control points. The procedures are divided into...

  11. Major tanker spill off Spain under control

    SciTech Connect

    Not Available

    1992-12-14

    This paper reports that a 23 sq mile oil slick along Spain's northwest coast, spreading form the wreckage of the Greek oil tanker Aegean Sea, was for the most part under control as of Dec. 10, Spanish authorities reported. Various press reports put the total spill volume at 490,000 bbl, about double that leaked by the Exxon Valdez supertanker off Alaska in 1989. If initial reports of the spill volume are borne out, the Aegean Sea spill would rank at least as one of the 10 biggest tanker spills.

  12. Polio control after certification: major issues outstanding.

    PubMed Central

    Fine, Paul E. M.; Oblapenko, George; Sutter, Roland W.

    2004-01-01

    Now that the global eradication of wild poliovirus is almost within sight, planning for the post-certification era is becoming a priority issue. It is agreed that a stockpile of appropriate polio vaccines will need to be established, and a surveillance and response capacity will need to be maintained, in order to protect the world against any possible future outbreaks attributable either to the persistence of wild poliovirus or vaccine-derived polioviruses (VDPVs) or to the unintentional or intentional release of poliovirus from a laboratory or vaccine store. Although it has been suggested that the stockpile should consist of monovalent oral poliovirus vaccine (mOPV), many questions remain concerning its nature, financing, management, and use--in particular, because of uncertainties over future national vaccination policies, and over the availability of different vaccines, after the certification of wild poliovirus eradication. There are further uncertainties concerning the possible role and efficacy of inactivated poliovirus vaccine (IPV) used either routinely or in outbreak control in low-hygiene settings, the potential for rapid geographical spread of polioviruses should an outbreak occur after certification, and the risks inherent in introducing additional oral polio vaccine (OPV) viruses into populations in which the vaccine coverage and prevalence of immunity have declined, and which may thus favour the spread of VDPVs. Given these important gaps in knowledge, no country should discontinue polio vaccination until a coordinated policy for the post-certification era has been developed and the recommended measures have been put in place. PMID:15106300

  13. 49 CFR 236.404 - Signals at adjacent control points.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Traffic Control Systems Standards § 236.404 Signals at adjacent control points. Signals at adjacent controlled... 49 Transportation 4 2011-10-01 2011-10-01 false Signals at adjacent control points....

  14. 49 CFR 236.404 - Signals at adjacent control points.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Traffic Control Systems Standards § 236.404 Signals at adjacent control points. Signals at adjacent controlled... 49 Transportation 4 2010-10-01 2010-10-01 false Signals at adjacent control points....

  15. MSFC Skylab attitude and pointing control system mission evaluation

    NASA Technical Reports Server (NTRS)

    Chubb, W. B.

    1974-01-01

    The results of detailed performance analyses of the attitude and pointing control system in-orbit hardware and software on Skylab are reported. Performance is compared with requirements, test results, and prelaunch predictions. A brief history of the altitude and pointing control system evolution leading to the launch configuration is presented. The report states that the attitude and pointing system satisfied all requirements.

  16. Pointing control design for autonomous space vehicle applications

    SciTech Connect

    Young, K.D.

    1993-03-01

    This paper addresses the design of pointing control systems for autonomous space vehicles. The function of the pointing control system is to keep distant orbiting objects within the field-of-view of an on-board optical sensor. We outline the development of novel nonlinear control algorithms which exploit the availability of on- board sensors. Simulation results comparing the performance of the different pointing control implementations are presented.

  17. Validation of acid washes as critical control points in hazard analysis and critical control point systems.

    PubMed

    Dormedy, E S; Brashears, M M; Cutter, C N; Burson, D E

    2000-12-01

    A 2% lactic acid wash used in a large meat-processing facility was validated as an effective critical control point (CCP) in a hazard analysis and critical control point (HACCP) plan. We examined the microbial profiles of beef carcasses before the acid wash, beef carcasses immediately after the acid wash, beef carcasses 24 h after the acid wash, beef subprimal cuts from the acid-washed carcasses, and on ground beef made from acid-washed carcasses. Total mesophilic, psychrotrophic, coliforms, generic Escherichia coli, lactic acid bacteria, pseudomonads, and acid-tolerant microorganisms were enumerated on all samples. The presence of Salmonella spp. was also determined. Acid washing significantly reduced all counts except for pseudomonads that were present at very low numbers before acid washing. All other counts continued to stay significantly lower (P < 0.05) than those on pre-acid-washed carcasses throughout all processing steps. Total bacteria, coliforms, and generic E. coli enumerated on ground beef samples were more than 1 log cycle lower than those reported in the U.S. Department of Agriculture Baseline data. This study suggests that acid washes may be effective CCPs in HACCP plans and can significantly reduce the total number of microorganisms present on the carcass and during further processing.

  18. Fine pointing control for free-space optical communication

    NASA Technical Reports Server (NTRS)

    Portillo, A. A.; Ortiz, G. G.; Racho, C.

    2000-01-01

    Free-Space Optical Communications requires precise, stable laser pointing to maintain operating conditions. This paper also describes the software and hardware implementation of Fine Pointing Control based on the Optical Communications Demonstrator architecture.

  19. End Point Control of Flexible Manipulators

    DTIC Science & Technology

    1988-10-01

    robots . Some of the tasks that have been achieved include making contact with objects, exerting controlled forces on objects, and making rapid motions ...nonlinear equations of motion which are more representative of modern industrial robots . Not only has stable colocated dosed loop control been...handed. The SCARA configuration keeps the first two links (those with the greatest mass and moment arms) in the horizontal plane . This configuration

  20. Control points within the cell cycle

    SciTech Connect

    Van't Hof, J.

    1984-01-01

    Evidence of the temporal order of chromosomal DNA replication argues favorably for the view that the cell cycle is controlled by genes acting in sequence whose time of expression is determined by mitosis and the amount of nuclear DNA (2C vs 4C) in the cell. Gl and G2 appear to be carbohydrate dependent in that cells starved of either carbohydrate of phosphate fail to make these transitions. Cells deprived of nitrate, however, fail only at Gl to S transition indicating that the controls that operate in G1 differ from those that operate in G2. 46 references, 5 figures.

  1. Strike Point Control for the National Spherical Torus Experiment (NSTX)

    SciTech Connect

    Kolemen, E.; Gates, D. A.; Rowley, C. W.; Kasdin, N. J.; Kallman, J.; Gerhardt, S.; Soukhanovskii, V.; Mueller, D.

    2010-07-09

    This paper presents the first control algorithm for the inner and outer strike point position for a Spherical Torus (ST) fusion experiment and the performance analysis of the controller. A liquid lithium divertor (LLD) will be installed on NSTX which is believed to provide better pumping than lithium coatings on carbon PFCs. The shape of the plasma dictates the pumping rate of the lithium by channeling the plasma to LLD, where strike point location is the most important shape parameter. Simulations show that the density reduction depends on the proximity of strike point to LLD. Experiments were performed to study the dynamics of the strike point, design a new controller to change the location of the strike point to desired location and stabilize it. The most effective PF coils in changing inner and outer strike points were identified using equilibrium code. The PF coil inputs were changed in a step fashion between various set points and the step response of the strike point position was obtained. From the analysis of the step responses, PID controllers for the strike points were obtained and the controller was tuned experimentally for better performance. The strike controller was extended to include the outer-strike point on the inner plate to accommodate the desired low outer-strike points for the experiment with the aim of achieving "snowflake" divertor configuration in NSTX.

  2. Mass Measurements beyond the Major r-Process Waiting Point {sup 80}Zn

    SciTech Connect

    Baruah, S.; Herlert, A.; Schweikhard, L.; Audi, G.; Guenaut, C.; Lunney, D.; Blaum, K.; George, S.; Dworschak, M.; Herfurth, F.; Yazidjian, C.; Hager, U.; Kellerbauer, A.; Kluge, H.-J.; Schatz, H.

    2008-12-31

    High-precision mass measurements on neutron-rich zinc isotopes {sup 71m,72-81}Zn have been performed with the Penning trap mass spectrometer ISOLTRAP. For the first time, the mass of {sup 81}Zn has been experimentally determined. This makes {sup 80}Zn the first of the few major waiting points along the path of the astrophysical rapid neutron-capture process where neutron-separation energy and neutron-capture Q-value are determined experimentally. The astrophysical conditions required for this waiting point and its associated abundance signatures to occur in r-process models can now be mapped precisely. The measurements also confirm the robustness of the N=50 shell closure for Z=30.

  3. Generalizations of fuzzy linguistic control points in geometric design

    NASA Astrophysics Data System (ADS)

    Sallehuddin, M. H.; Wahab, A. F.; Gobithaasan, R. U.

    2014-07-01

    Control points are geometric primitives that play an important role in designing the geometry curve and surface. When these control points are blended with some basis functions, there are several geometric models such as Bezier, B-spline and NURBS(Non-Uniform Rational B-Spline) will be produced. If the control points are defined by the theory of fuzzy sets, then fuzzy geometric models are produced. But the fuzzy geometric models can only solve the problem of uncertainty complex. This paper proposes a new definition of fuzzy control points with linguistic terms. When the fuzzy control points with linguistic terms are blended with basis functions, then a fuzzy linguistic geometric model is produced. This paper ends with some numerical examples illustrating linguistic control attributes of fuzzy geometric models.

  4. All sky pointing attitude control system

    NASA Technical Reports Server (NTRS)

    Lorell, K. R.; Murphy, J. P. (Inventor)

    1977-01-01

    In a strapped-down gyroscope space vehicle attitude control system, a method and apparatus are provided for gyro drift and input axis misalignment error compensation employing a sun and a star tracker and preselected vehicle calibration maneuvers. The outputs of two-axis strapped-down gyroscopes nominally aligned with the optical axis of the sun and star trackers are measured to provide gyro drift calibration, roll, pitch and yaw axis scale factors and values corresponding to the degree of nonorthogonality between the roll axis and the pitch and yaw gyro input axes and the nonorthogonality of the roll and pitch axes relative to the yaw axis. The vehicle is then rolled and yawed through precomputed angles as modified by the calibrated data stored in a digital computer, and acquires a target without recourse to external references.

  5. Reconfigurable Pointing Control for High Resolution Space Spectroscopy

    NASA Technical Reports Server (NTRS)

    Bayard, David S.; Kia, Tooraj; Van Cleve, Jeffrey

    1997-01-01

    In this paper, a pointing control performance criteria is established to suppport high resolution space spectroscopy. Results indicate that these pointing control requirements are very stringent, and would typically be difficult to meet using standard 3-axis spacecraft control. To resolve this difficulty, it is shown that performance can be significantly improved using a reconfigurable control architecture that switches among a small bankof detuned Kalman filters. The effectiveness of the control reconfiguration approach is demonstrated by example on the Space Infra-Red Telescope Facility (SIRTF) pointing system, in support of the InfraRed Spectrograph (IRS) payload.

  6. Point-to-Point Ultra-Remote Asymmetric Control with Flexible Linker.

    PubMed

    Kawasaki, Tsuneomi; Ishikawa, Yasuyuki; Minato, Yoshihiro; Otsuka, Takashi; Yonekubo, Shigeru; Sato, Itaru; Shibata, Takanori; Matsumoto, Arimasa; Soai, Kenso

    2017-01-05

    An ultra-remote intramolecular (point-to-point) asymmetric control through 38 bonds (1,39-asymmetric induction) has been achieved by using the principle of direct supramolecular orientation of catalytic and reactive moieties in asymmetric autocatalysis. We found the highly stereoselective diisopropylzinc addition reaction using designed molecules possessing pyrimidine sites at each terminal of a conformationally flexible simple methylene chain.

  7. Reconfigurable Pointing Control for High Resolution Space Spectroscopy

    NASA Technical Reports Server (NTRS)

    Bayard, David S.; Kia, Tooraj; vanCleve, Jeffrey

    1997-01-01

    In this paper, a pointing control performance criteria is established to support high resolution space spectroscopy. Results indicate that these pointing requirements are very stringent, and would typically be difficult to meet using standard 3-axis spacecraft control. To resolve this difficulty, it is shown that performance can be significantly improved using a reconfigurable control architecture that switches among a small bank of detuned Kalman filters. The effectiveness of the control reconfiguration approach is demonstrated by example on the Space Infra, Red Telescope Facility (SIRTF) pointing system, in support of the Infrared Spectrograph (IRS) payload.

  8. Onboard utilization of ground control points for image correction. Volume 3: Ground control point simulation software design

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The software developed to simulate the ground control point navigation system is described. The Ground Control Point Simulation Program (GCPSIM) is designed as an analysis tool to predict the performance of the navigation system. The system consists of two star trackers, a global positioning system receiver, a gyro package, and a landmark tracker.

  9. Shuttle infrared telescope facility pointing and control system

    NASA Technical Reports Server (NTRS)

    Lorell, K. R.; Barrows, W. F.; Matsumoto, Y. T.

    1981-01-01

    The Shuttle Infrared Telescope Facility (SIRTF) is being designed as a 0.85 m cryogenically cooled telescope capable of a three order of magnitude improvement over currently available infrared instruments. The SIRTF requires that the image at the focal plane be stabilized to better than 0.25 arcsec with an absolute accuracy of 1.0 arcsec. Current pointing-mount performance simulations indicate that neither of these requirements can be met without additional stabilization. The SIRTF pointing and control system will utilize gyro outputs, star field position measurements from a focal plane fine guidance sensor, and a steerable secondary mirror to provide the necessary stabilization and pointing control. The charge coupled device fine guidance sensor tracks multiple stars simultaneously and, through the use of multistar processing algorithms in a high performance microcomputer, generates three-axis attitude errors and gyro-drift estimates to correct the pointing-mount gyros. A high-bandwidth feedforward loop, driven directly from the pointing-mount gyro package, controls the steering mirror in order to correct disturbances not compensated for by the pointing-mount control system. A prototype design for the SIRTF pointing and control system is described in detail. Performance analyses made using a digital simulation of the pointing and control system as well as experimental data obtained in laboratory and field test measurements are presented.

  10. A multiple pointing-mount control strategy for space platforms

    NASA Technical Reports Server (NTRS)

    Johnson, C. D.

    1992-01-01

    A new disturbance-adaptive control strategy for multiple pointing-mount space platforms is proposed and illustrated by consideration of a simplified 3-link dynamic model of a multiple pointing-mount space platform. Simulation results demonstrate the effectiveness of the new platform control strategy. The simulation results also reveal a system 'destabilization phenomena' that can occur if the set of individual platform-mounted experiment controllers are 'too responsive.'

  11. Octopuses use a human-like strategy to control precise point-to-point arm movements.

    PubMed

    Sumbre, Germán; Fiorito, Graziano; Flash, Tamar; Hochner, Binyamin

    2006-04-18

    One of the key problems in motor control is mastering or reducing the number of degrees of freedom (DOFs) through coordination. This problem is especially prominent with hyper-redundant limbs such as the extremely flexible arm of the octopus. Several strategies for simplifying these control problems have been suggested for human point-to-point arm movements. Despite the evolutionary gap and morphological differences, humans and octopuses evolved similar strategies when fetching food to the mouth. To achieve this precise point-to-point-task, octopus arms generate a quasi-articulated structure based on three dynamic joints. A rotational movement around these joints brings the object to the mouth . Here, we describe a peripheral neural mechanism-two waves of muscle activation propagate toward each other, and their collision point sets the medial-joint location. This is a remarkably simple mechanism for adjusting the length of the segments according to where the object is grasped. Furthermore, similar to certain human arm movements, kinematic invariants were observed at the joint level rather than at the end-effector level, suggesting intrinsic control coordination. The evolutionary convergence to similar geometrical and kinematic features suggests that a kinematically constrained articulated limb controlled at the level of joint space is the optimal solution for precise point-to-point movements.

  12. Nonpoint and Point Sources of Nitrogen in Major Watersheds of the United States

    USGS Publications Warehouse

    Puckett, Larry J.

    1994-01-01

    Estimates of nonpoint and point sources of nitrogen were made for 107 watersheds located in the U.S. Geological Survey's National Water-Quality Assessment Program study units throughout the conterminous United States. The proportions of nitrogen originating from fertilizer, manure, atmospheric deposition, sewage, and industrial sources were found to vary with climate, hydrologic conditions, land use, population, and physiography. Fertilizer sources of nitrogen are proportionally greater in agricultural areas of the West and the Midwest than in other parts of the Nation. Animal manure contributes large proportions of nitrogen in the South and parts of the Northeast. Atmospheric deposition of nitrogen is generally greatest in areas of greatest precipitation, such as the Northeast. Point sources (sewage and industrial) generally are predominant in watersheds near cities, where they may account for large proportions of the nitrogen in streams. The transport of nitrogen in streams increases as amounts of precipitation and runoff increase and is greatest in the Northeastern United States. Because no single nonpoint nitrogen source is dominant everywhere, approaches to control nitrogen must vary throughout the Nation. Watershed-based approaches to understanding nonpoint and point sources of contamination, as used by the National Water-Quality Assessment Program, will aid water-quality and environmental managers to devise methods to reduce nitrogen pollution.

  13. Laying medicine open: understanding major turning points in the history of medical ethics.

    PubMed

    McCullough, Laurence B

    1999-03-01

    At different times during its history medicine has been laid open to accountability for its scientific and moral quality. This phenonmenon of laying medicine open has sometimes resulted in major turning points in the history of medical ethics. In this paper, I examine two examples of when the laying open of medicine has generated such turning points: eighteenth-century British medicine and late twentieth-century American medicine. In the eighteenth century, the Scottish physician-philosopher, John Gregory (1724-1773), concerned with the unscientific, entrepreneurial, self-interested nature of then current medical practice, laid medicine open to accountability using the tools of ethics and philosophy of medicine. In the process, Gregory wrote the first professional ethics of medicine in the English-language literature, based on the physician's fiduciary responsibility to the patient. In the late twentieth century, the managed practice of medicine has laid medicine open to accountability for its scientific quality and economic cost. This current laying open of medicine creates the challenge of developing medical ethics and bioethics for population-based medical science and practice.

  14. Appropriate Depth of Needle Insertion During Rhomboid Major Trigger Point Block

    PubMed Central

    Seol, Seung Jun; Cho, Hyungpil; Yoon, Do Hyun

    2014-01-01

    Objective To investigate an appropriate depth of needle insertion during trigger point injection into the rhomboid major muscle. Methods Sixty-two patients who visited our department with shoulder or upper back pain participated in this study. The distance between the skin and the rhomboid major muscle (SM) and the distance between the skin and rib (SB) were measured using ultrasonography. The subjects were divided into 3 groups according to BMI: BMI less than 23 kg/m2 (underweight or normal group); 23 kg/m2 or more to less than 25 kg/m2 (overweight group); and 25 kg/m2 or more (obese group). The mean±standard deviation (SD) of SM and SB of each group were calculated. A range between mean+1 SD of SM and the mean-1 SD of SB was defined as a safe margin. Results The underweight or normal group's SM, SB, and the safe margin were 1.2±0.2, 2.1±0.4, and 1.4 to 1.7 cm, respectively. The overweight group's SM and SB were 1.4±0.2 and 2.4±0.9 cm, respectively. The safe margin could not be calculated for this group. The obese group's SM, SB, and the safe margin were 1.8±0.3, 2.7±0.5, and 2.1 to 2.2 cm, respectively. Conclusion This study will help us to set the standard depth of safe needle insertion into the rhomboid major muscle in an effective manner without causing any complications. PMID:24639929

  15. Cognitive control in majority search: a computational modeling approach.

    PubMed

    Wang, Hongbin; Liu, Xun; Fan, Jin

    2011-01-01

    Despite the importance of cognitive control in many cognitive tasks involving uncertainty, the computational mechanisms of cognitive control in response to uncertainty remain unclear. In this study, we develop biologically realistic neural network models to investigate the instantiation of cognitive control in a majority function task, where one determines the category to which the majority of items in a group belong. Two models are constructed, both of which include the same set of modules representing task-relevant brain functions and share the same model structure. However, with a critical change of a model parameter setting, the two models implement two different underlying algorithms: one for grouping search (where a subgroup of items are sampled and re-sampled until a congruent sample is found) and the other for self-terminating search (where the items are scanned and counted one-by-one until the majority is decided). The two algorithms hold distinct implications for the involvement of cognitive control. The modeling results show that while both models are able to perform the task, the grouping search model fit the human data better than the self-terminating search model. An examination of the dynamics underlying model performance reveals how cognitive control might be instantiated in the brain for computing the majority function.

  16. Cognitive Control in Majority Search: A Computational Modeling Approach

    PubMed Central

    Wang, Hongbin; Liu, Xun; Fan, Jin

    2011-01-01

    Despite the importance of cognitive control in many cognitive tasks involving uncertainty, the computational mechanisms of cognitive control in response to uncertainty remain unclear. In this study, we develop biologically realistic neural network models to investigate the instantiation of cognitive control in a majority function task, where one determines the category to which the majority of items in a group belong. Two models are constructed, both of which include the same set of modules representing task-relevant brain functions and share the same model structure. However, with a critical change of a model parameter setting, the two models implement two different underlying algorithms: one for grouping search (where a subgroup of items are sampled and re-sampled until a congruent sample is found) and the other for self-terminating search (where the items are scanned and counted one-by-one until the majority is decided). The two algorithms hold distinct implications for the involvement of cognitive control. The modeling results show that while both models are able to perform the task, the grouping search model fit the human data better than the self-terminating search model. An examination of the dynamics underlying model performance reveals how cognitive control might be instantiated in the brain for computing the majority function. PMID:21369357

  17. Digital controller design: Analysis of the annular suspension pointing system

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The annular suspension and pointing system (ASPS) a payload auxiliary pointing device of the space shuttle is briefly described along with the function of the digital controller. The equations of motion of a simplified plan planar model of the ASPS are derived. Results of computer simulations are discussed.

  18. Conceptual design of pointing control systems for space station gimballed payloads

    NASA Technical Reports Server (NTRS)

    Hughes, Robert O.

    1986-01-01

    A conceptual design of the control system for Payload Pointing Systems (PPS) is developed using classic Proportional-Integral-Derivatives (PID) techniques. The major source of system pointing error is due to the disturbance-rich environment of the space station in the form of gimbal baseplate motions. These baseplate vibrations are characterized using Fast Fourier Transform (FFT) techniques. Both time domain and frequency domain dynamic models are developed to assess control system performance. Three basic methods exist for the improvement of PPS pointing performance: increase control system bandwidth, add Image Motion Compensation, and/or reduce (or change) the baseplate disturbance environment.

  19. Implementation of hazard analysis critical control point in jameed production.

    PubMed

    Al-Saed, A K; Al-Groum, R M; Al-Dabbas, M M

    2012-06-01

    The average of standard plate count and coliforms, Staphylococcus aureus and Salmonella counts for three home-made jameed samples, a traditional fermented dairy product, before applying hazard analysis critical control point system were 2.1 × 10(3), 8.9 × 10(1), 4 × 10(1) and less than 10 cfu/g, respectively. The developed hazard analysis critical control point plan resulted in identifying ten critical control points in the flow chart of jameed production. The critical control points included fresh milk receiving, pasteurization, addition of starter, water and salt, straining, personnel hygiene, drying and packaging. After applying hazard analysis critical control point system, there was significant improvement in the microbiological quality of the home-made jameed. The standard plate count was reduced to 3.1 × 10(2) cfu/g whereas coliform and Staphylococcus aureus counts were less than 10 cfu/g and Salmonella was not detected. Sensory evaluation results of color and flavor of sauce prepared from jameed showed a significant increase in the average scores given after hazard analysis critical control point application.

  20. Annular suspension and pointing system with controlled DC electromagnets

    NASA Technical Reports Server (NTRS)

    Vu, Josephine Lynn; Tam, Kwok Hung

    1993-01-01

    The Annular Suspension and Pointing System (ASPS) developed by the Flight System division of Sperry Corporation is a six-degree of freedom payload pointing system designed for use with the space shuttle. This magnetic suspension and pointing system provides precise controlled pointing in six-degrees of freedom, isolation of payload-carrier disturbances, and end mount controlled pointing. Those are great advantages over the traditional mechanical joints for space applications. In this design, we first analyzed the assumed model of the single degree ASPS bearing actuator and obtained the plant dynamics equations. By linearizing the plant dynamics equations, we designed the cascade and feedback compensators such that a stable and satisfied result was obtained. The specified feedback compensator was computer simulated with the nonlinearized plant dynamics equations. The results indicated that an unstable output occurred. In other words, the designed feedback compensator failed. The failure of the design is due to the Taylor's series expansion not converging.

  1. Assisted Control Point Measurement for Close Range Photogrammetry.

    NASA Astrophysics Data System (ADS)

    Mata, E.; Hernandez, M. A.; Cardenal, J.; Perez, J. L.

    2012-07-01

    This paper describes the automation and optimization in control points measurement and elaboration of sketches in Close Range Photogrammetry. The system can be controlled by an operator alone and it integrates a robotized and reflectorless total station, two digital cameras, a laptop computer and the control software. The measured data with the station are registered and the control point will get associated to their marks in the images. So, it is possible to eliminate the handmade sketches since the marking of control points in the image is instantaneously made. The sketch includes object images with enlargements so the point is clearly identified and marked with the support of a virtual reticle. Also the sketch includes object coordinates, image coordinates, identification code (ID) and some additional information about the point. The use of the system by only one operator allows the reduction of costs, organization and time in control point surveying. Different tests have been made in order to check the system. TDC: this test has been made in close range conditions with targets and artificial illumination. EDIF: in this case the test includes long range conditions and control points targeted at natural points in building façade. The tests have allowed several analyses to study the feasibility and the improvement of the system. So we have made in situ tests by comparing direct observations with and without the camera telescope, with targets and natural points, close and long distances and different conditions of illumination. Moreover in one of these tests we include the observation and sketch realization with a manual method. With respect to the use of the aiming eyepiece camera, the tests (TDC) realized in laboratory (close distance -4 m- and good light conditions) show very small spatial differences (below the nominal precision of the total station) comparing the direct aim through the telescope without camera. Other test (EDIF) made over longer distance (130

  2. Feedback control of major disruptions in International Thermonuclear Experimental Reactor

    SciTech Connect

    Sen, A. K.

    2011-08-15

    It is argued that major disruptions in ITER can be avoided by the feedback control of the causative MHD precursors. The sensors will be 2D-arrays of ECE detectors and the suppressors will be modulated ECH beams injected radially to produce non-thermal radial pressures to counter the radial dynamics of MHD modes. The appropriate amplitude and phase of this signal can stabilize the relevant MHD modes and prevent their evolution to a major disruption. For multimode MHD precursors, an optimal feedback scheme with a Kalman filter is discussed.

  3. Generating controllable type-II Weyl points via periodic driving

    NASA Astrophysics Data System (ADS)

    Bomantara, Raditya Weda; Gong, Jiangbin

    2016-12-01

    Type-II Weyl semimetals are a novel gapless topological phase of matter discovered recently in 2015. Similar to normal (type-I) Weyl semimetals, type-II Weyl semimetals consist of isolated band touching points. However, unlike type-I Weyl semimetals which have a linear energy dispersion around the band touching points forming a three-dimensional (3D) Dirac cone, type-II Weyl semimetals have a tilted conelike structure around the band touching points. This leads to various novel physical properties that are different from type-I Weyl semimetals. In order to study further the properties of type-II Weyl semimetals and perhaps realize them for future applications, generating controllable type-II Weyl semimetals is desirable. In this paper, we propose a way to generate a type-II Weyl semimetal via a generalized Harper model interacting with a harmonic driving field. When the field is treated classically, we find that only type-I Weyl points emerge. However, by treating the field quantum mechanically, some of these type-I Weyl points may turn into type-II Weyl points. Moreover, by tuning the coupling strength, it is possible to control the tilt of the Weyl points and the energy difference between two Weyl points, which makes it possible to generate a pair of mixed Weyl points of type-I and type-II. We also discuss how to physically distinguish these two types of Weyl points in the framework of our model via the Landau level structures in the presence of an artificial magnetic field. The results are of general interest to quantum optics as well as ongoing studies of Floquet topological phases.

  4. Space telescope - Meeting the pointing control challenge with today's technology

    NASA Technical Reports Server (NTRS)

    Dougherty, H.; Rodoni, C.; Rodden, J.; Tompetrini, K.

    1982-01-01

    The pointing control system of the Space Telescope, which provides target-to-target maneuvering capability and precision pointing on the target star (with 0.007-arcsec stability and 0.01-arcsec accuracy), is described. Spacecraft attitude control is undertaken by onboard computer processing of attitude and rate sensor data that generates reaction wheel torque commands. The Space Telescope Operations Control Center communicates with the Space Telescope via the synchronous altitude tracking and data relay satellite system, and determines vehicle attitude more precisely by means of sun sensors, magnetometers and fixed-head star trackers. Such disturbance torques as those of gravity gradients and aerodynamics act on the Space Telescope, causing the speeds of the four reaction wheels to increase. In order to prevent the wheels from reaching a speed-saturated condition, a momentum control system is provided for the management of reaction wheel speed buildup. Attention is given to development testing and control hardware investigations and improvements.

  5. Pointing and Scanning Control of Instruments Using Rotating Unbalanced Masses

    NASA Technical Reports Server (NTRS)

    Hung, John Y.

    1996-01-01

    Motions of telescopes, satellites, and other flight bodies have been controlled by various means in the past. For example, gimbal mounted devices can use electric motors to produce pointing and scanning motions. Reaction wheels, control moment gyros, and propellant-charged reaction jets are other technologies that have also been used. Each of these methods has its advantages, but all actuator systems used in a flight environment face the challenges of minimizing weight, reducing energy consumption, and maximizing reliability. Recently, Polites invented and patented the Rotating Unbalanced Mass (RUM) device as a means for generation scanning motion on flight experiments. RUM devices have been successfully used to generate various scanning motions. The basic principle: a RUM rotating at constant annular velocity exerts a cyclic centrifugal force on the instrument or main body, thus producing a periodic scanning motion. A system of RUM devices exerts no reaction forces on the main body, requires very little energy, and is very simple to construct and control. These are significant advantages over electric motors, reaction wheels, and control moment gyroscopes. Although the RUM device very easily produces scanning motion, an auxiliary control system may be required to maintain the proper orientation, or pointing of the main body. It has been suggested that RUM devices can be used to control pointing dynamics, as well as generate the desired periodic scanning motion. The idea is that the RUM velocity will not be constant, but will vary over the period of one RUM rotation. The thought is that the changing angular velocity produces a centrifugal force having time-varying magnitude and direction. The scope of the present research project is to further study the pointing control concept, and to implement a microcontroller program to control an experimental hardware system. This report is subdivided into three themes. The basic dynamic modeling and control principles are

  6. Cognitive control adjustments and conflict adaptation in major depressive disorder.

    PubMed

    Clawson, Ann; Clayson, Peter E; Larson, Michael J

    2013-08-01

    Individuals with major depressive disorder (MDD) show alterations in the cognitive control function of conflict processing. We examined the influence of these deficits on behavioral and event-related potential (ERP) indices of conflict adaptation, a cognitive control process wherein previous-trial congruency modulates current-trial performance, in 55 individuals with MDD and 55 matched controls. ERPs were calculated while participants completed a modified flanker task. There were nonsignificant between-groups differences in response time, error rate, and N2 indices of conflict adaptation. Higher depressive symptom scores were associated with smaller mean N2 conflict adaptation scores for individuals with MDD and when collapsed across groups. Results were consistent when comorbidity and medications were analyzed. These findings suggest N2 conflict adaptation is associated with depressive symptoms rather than clinical diagnosis alone.

  7. Pointing control for the SPIDER balloon-borne telescope

    NASA Astrophysics Data System (ADS)

    Shariff, J. A.; Ade, P. A. R.; Amiri, M.; Benton, S. J.; Bock, J. J.; Bond, J. R.; Bryan, S. A.; Chiang, H. C.; Contaldi, C. R.; Crill, B. P.; Doré, O. P.; Farhang, M.; Filippini, J. P.; Fissel, L. M.; Fraisse, A. A.; Gambrel, A. E.; Gandilo, N. N.; Golwala, S. R.; Gudmundsson, J. E.; Halpern, M.; Hasselfield, M.; Hilton, G. C.; Holmes, W. A.; Hristov, V. V.; Irwin, K. D.; Jones, W. C.; Kermish, Z. D.; Kuo, C. L.; MacTavish, C. J.; Mason, P. V.; Megerian, K. G.; Moncelsi, L.; Morford, T. A.; Nagy, J. M.; Netterfield, C. B.; O'Brient, R.; Rahlin, A. S.; Reintsema, C. D.; Ruhl, J. E.; Runyan, M. C.; Soler, J. D.; Trangsrud, A.; Tucker, C. E.; Tucker, R. S.; Turner, A. D.; Weber, A. C.; Wiebe, D. V.; Young, E. Y.

    2014-07-01

    We present the technology and control methods developed for the pointing system of the Spider experiment. Spider is a balloon-borne polarimeter designed to detect the imprint of primordial gravitational waves in the polarization of the Cosmic Microwave Background radiation. We describe the two main components of the telescope's azimuth drive: the reaction wheel and the motorized pivot. A 13 kHz PI control loop runs on a digital signal processor, with feedback from fibre optic rate gyroscopes. This system can control azimuthal speed with < 0.02 deg/s RMS error. To control elevation, Spider uses stepper-motor-driven linear actuators to rotate the cryostat, which houses the optical instruments, relative to the outer frame. With the velocity in each axis controlled in this way, higher-level control loops on the onboard flight computers can implement the pointing and scanning observation modes required for the experiment. We have accomplished the non-trivial task of scanning a 5000 lb payload sinusoidally in azimuth at a peak acceleration of 0.8 deg/s2, and a peak speed of 6 deg/s. We can do so while reliably achieving sub-arcminute pointing control accuracy.

  8. LST data management and mission operations concept. [pointing control optimization for maximum data

    NASA Technical Reports Server (NTRS)

    Walker, R.; Hudson, F.; Murphy, L.

    1977-01-01

    A candidate design concept for an LST ground facility is described. The design objectives were to use NASA institutional hardware, software and facilities wherever practical, and to maximize efficiency of telescope use. The pointing control performance requirements of LST are summarized, and the major data interfaces of the candidate ground system are diagrammed.

  9. Fine pointing control for a Next-Generation Space Telescope

    NASA Astrophysics Data System (ADS)

    Mosier, Gary E.; Femiano, Michael; Ha, Kong; Bely, Pierre Y.; Burg, Richard; Redding, David C.; Kissil, Andrew; Rakoczy, John; Craig, Larry

    1998-08-01

    The Next Generation Space Telescope will provide at least ten times the collecting area of the Hubble Space Telescope in a package that fits into the shroud of an expendable launch vehicle. The resulting large, flexible structure provides a challenge to the design of a pointing control system for which the requirements are at the milli-arcsecond level. This paper describes a design concept in which pointing stability is achieved by means of a nested-loop design involving an inertial attitude control system (ACS) and a fast steering mirror (FSM). A key to the integrated control design is that the ACS controllers has a bandwidth well below known structural modes and the FSM uses a rotationally balanced mechanism which should not interact with the flexible modes that are within its control bandwidth. The ACS controller provides stable pointing of the spacecraft bus with star trackers and gyros. This low bandwidth loop uses nearly co-located sensors and actuators to slew and acquire faint guide stars in the NIR camera. This controller provides a payload reference stable to the arcsecond level. Low-frequency pointing errors due to sensor noise and dynamic disturbances are suppressed by a 2-axis gimbaled FSM locate din the instrument module. The FSM servo bandwidth of 6 Hz is intended to keep the guide star position stable in the NIR focal plane to the required milli-arcsecond level. The mirror is kept centered in its range of travel by a low-bandwidth loop closed around the ACS. This paper presents the result of parametric trade studies designed to assess the performance of this control design in the presence of modeled reaction wheel disturbances, assumed to be the principle source of vibration for the NGST, and variations in structural dynamics. Additionally, requirements for reaction wheel disturbance levels and potential vibration isolation subsystems were developed.

  10. Engineering to Control Noise, Loading, and Optimal Operating Points

    SciTech Connect

    Mitchell R. Swartz

    2000-11-12

    Successful engineering of low-energy nuclear systems requires control of noise, loading, and optimum operating point (OOP) manifolds. The latter result from the biphasic system response of low-energy nuclear reaction (LENR)/cold fusion systems, and their ash production rate, to input electrical power. Knowledge of the optimal operating point manifold can improve the reproducibility and efficacy of these systems in several ways. Improved control of noise, loading, and peak production rates is available through the study, and use, of OOP manifolds. Engineering of systems toward the OOP-manifold drive-point peak may, with inclusion of geometric factors, permit more accurate uniform determinations of the calibrated activity of these materials/systems.

  11. Two Axis Pointing System (TAPS) attitude acquisition, determination, and control

    NASA Technical Reports Server (NTRS)

    Azzolini, John D.; Mcglew, David E.

    1990-01-01

    The Two Axis Pointing System (TAPS) is a 2 axis gimbal system designed to provide fine pointing of Space Transportation System (STS) borne instruments. It features center-of-mass instrument mounting and will accommodate instruments of up to 1134 kg (2500 pounds) which fit within a 1.0 by 1.0 by 4.2 meter (40 by 40 by 166 inch) envelope. The TAPS system is controlled by a microcomputer based Control Electronics Assembly (CEA), a Power Distribution Unit (PDU), and a Servo Control Unit (SCU). A DRIRU-II inertial reference unit is used to provide incremental angles for attitude propagation. A Ball Brothers STRAP star tracker is used for attitude acquisition and update. The theory of the TAPS attitude determination and error computation for the Broad Band X-ray Telescope (BBXRT) are described. The attitude acquisition is based upon a 2 star geometric solution. The acquisition theory and quaternion algebra are presented. The attitude control combines classical position, integral and derivative (PID) control with techniques to compensate for coulomb friction (bias torque) and the cable harness crossing the gimbals (spring torque). Also presented is a technique for an adaptive bias torque compensation which adjusts to an ever changing frictional torque environment. The control stability margins are detailed, with the predicted pointing performance, based upon simulation studies. The TAPS user interface, which provides high level operations commands to facilitate science observations, is outlined.

  12. Two Axis Pointing System (TAPS) attitude acquisition, determination, and control

    NASA Astrophysics Data System (ADS)

    Azzolini, John D.; McGlew, David E.

    1990-12-01

    The Two Axis Pointing System (TAPS) is a 2 axis gimbal system designed to provide fine pointing of Space Transportation System (STS) borne instruments. It features center-of-mass instrument mounting and will accommodate instruments of up to 1134 kg (2500 pounds) which fit within a 1.0 by 1.0 by 4.2 meter (40 by 40 by 166 inch) envelope. The TAPS system is controlled by a microcomputer based Control Electronics Assembly (CEA), a Power Distribution Unit (PDU), and a Servo Control Unit (SCU). A DRIRU-II inertial reference unit is used to provide incremental angles for attitude propagation. A Ball Brothers STRAP star tracker is used for attitude acquisition and update. The theory of the TAPS attitude determination and error computation for the Broad Band X-ray Telescope (BBXRT) are described. The attitude acquisition is based upon a 2 star geometric solution. The acquisition theory and quaternion algebra are presented. The attitude control combines classical position, integral and derivative (PID) control with techniques to compensate for coulomb friction (bias torque) and the cable harness crossing the gimbals (spring torque). Also presented is a technique for an adaptive bias torque compensation which adjusts to an ever changing frictional torque environment. The control stability margins are detailed, with the predicted pointing performance, based upon simulation studies. The TAPS user interface, which provides high level operations commands to facilitate science observations, is outlined.

  13. Floating-point system quantization errors in digital control systems

    NASA Technical Reports Server (NTRS)

    Phillips, C. L.; Vallely, D. P.

    1978-01-01

    This paper considers digital controllers (filters) operating in floating-point arithmetic in either open-loop or closed-loop systems. A quantization error analysis technique is developed, and is implemented by a digital computer program that is based on a digital simulation of the system. The program can be integrated into existing digital simulations of a system.

  14. Galileo Spacecraft Scan Platform Celestial Pointing Cone Control Gain Redesign

    NASA Technical Reports Server (NTRS)

    In, C-H. C.; Hilbert, K. B.

    1994-01-01

    During September and October 1991, pictures of the Gaspra asteroid and neighboring stars were taken by the Galileo Optical Navigation (OPNAV) Team for the purpose of navigation the spacecraft for a successful Gaspra encounter. The star tracks in these pictures showed that the scan platform celestial pointing cone controller performed poorly in compensating for wobble-induced cone offsets.

  15. Triana Safehold: A New Gyroless, Sun-Pointing Attitude Controller

    NASA Technical Reports Server (NTRS)

    Chen, J.; Morgenstern, Wendy; Garrick, Joseph

    2001-01-01

    Triana is a single-string spacecraft to be placed in a halo orbit about the sun-earth Ll Lagrangian point. The Attitude Control Subsystem (ACS) hardware includes four reaction wheels, ten thrusters, six coarse sun sensors, a star tracker, and a three-axis Inertial Measuring Unit (IMU). The ACS Safehold design features a gyroless sun-pointing control scheme using only sun sensors and wheels. With this minimum hardware approach, Safehold increases mission reliability in the event of a gyroscope anomaly. In place of the gyroscope rate measurements, Triana Safehold uses wheel tachometers to help provide a scaled estimation of the spacecraft body rate about the sun vector. Since Triana nominally performs momentum management every three months, its accumulated system momentum can reach a significant fraction of the wheel capacity. It is therefore a requirement for Safehold to maintain a sun-pointing attitude even when the spacecraft system momentum is reasonably large. The tachometer sun-line rate estimation enables the controller to bring the spacecraft close to its desired sun-pointing attitude even with reasonably high system momentum and wheel drags. This paper presents the design rationale behind this gyroless controller, stability analysis, and some time-domain simulation results showing performances with various initial conditions. Finally, suggestions for future improvements are briefly discussed.

  16. 47 CFR 90.473 - Operation of internal transmitter control systems through licensed fixed control points.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Transmitter Control Internal Transmitter Control Systems § 90.473 Operation of internal transmitter control systems through licensed fixed control points. An internal transmitter control system may be operated... internal system from the transmitter control circuit or to close the system......

  17. 47 CFR 90.473 - Operation of internal transmitter control systems through licensed fixed control points.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Transmitter Control Internal Transmitter Control Systems § 90.473 Operation of internal transmitter control systems through licensed fixed control points. An internal transmitter control system may be operated... internal system from the transmitter control circuit or to close the system......

  18. Optimal periodic control for spacecraft pointing and attitude determination

    NASA Technical Reports Server (NTRS)

    Pittelkau, Mark E.

    1993-01-01

    A new approach to autonomous magnetic roll/yaw control of polar-orbiting, nadir-pointing momentum bias spacecraft is considered as the baseline attitude control system for the next Tiros series. It is shown that the roll/yaw dynamics with magnetic control are periodically time varying. An optimal periodic control law is then developed. The control design features a state estimator that estimates attitude, attitude rate, and environmental torque disturbances from Earth sensor and sun sensor measurements; no gyros are needed. The state estimator doubles as a dynamic attitude determination and prediction function. In addition to improved performance, the optimal controller allows a much smaller momentum bias than would otherwise be necessary. Simulation results are given.

  19. Improved pointing at trackable targets by integrating control valve signals

    NASA Technical Reports Server (NTRS)

    Stone, R. W.; Laverty, C. R.; Colby, M. J.

    1982-01-01

    A compact, low-cost add-on electronic module has been developed for the STRAP III control system to improve pointing at trackable targets. The module provides peak-to-peak limit cycle excursions of + or - 5 arcseconds while tracking a +3 magnitude or brighter star. This is achieved without using rate-integrating gyroscopes, thus reducing payload length, weight, cost, and preparation time. This module has flown successfully five times. In May 1981, it improved the performance of a two-startracker attitude control system with TV camera and joystick control which pointed at a nontrackable target. This paper describes the operation of the module, how it alters the ordinary STRAP III operation, and how it was developed using an analog-computer-based rocket flight simulator.

  20. Accuracy analysis of pointing control system of solar power station

    NASA Technical Reports Server (NTRS)

    Hung, J. C.; Peebles, P. Z., Jr.

    1978-01-01

    The first-phase effort concentrated on defining the minimum basic functions that the retrodirective array must perform, identifying circuits that are capable of satisfying the basic functions, and looking at some of the error sources in the system and how they affect accuracy. The initial effort also examined three methods for generating torques for mechanical antenna control, performed a rough analysis of the flexible body characteristics of the solar collector, and defined a control system configuration for mechanical pointing control of the array.

  1. Testing Set-Point Theory in a Swiss National Sample: Reaction and Adaptation to Major Life Events

    PubMed Central

    Anusic, Ivana; Yap, Stevie C. Y.; Lucas, Richard E.

    2014-01-01

    Set-point theory posits that individuals react to the experience of major life events, but quickly adapt back to pre-event baseline levels of subjective well-being in the years following the event. A large, nationally representative panel study of Swiss households was used to examine set-point theory by investigating the extent of adaptation following the experience of marriage, childbirth, widowhood, unemployment, and disability. Our results demonstrate that major life events are associated with marked change in life satisfaction and, for some events (e.g., marriage, disability), these changes are relatively long lasting even when accounting for normative, age related change. PMID:25419036

  2. Model-based HSF using by target point control function

    NASA Astrophysics Data System (ADS)

    Kim, Seongjin; Do, Munhoe; An, Yongbae; Choi, Jaeseung; Yang, Hyunjo; Yim, Donggyu

    2015-03-01

    As the technology node shrinks, ArF Immersion reaches the limitation of wafer patterning, furthermore weak point during the mask processing is generated easily. In order to make strong patterning result, the design house conducts lithography rule checking (LRC). Despite LRC processing, we found the weak point at the verification stage of optical proximity correction (OPC). It is called the hot spot point (HSP). In order to fix the HSP, many studies have been performed. One of the most general hot spot fixing (HSF) methods is that the modification bias which consists of "Line-Resizing" and "Space-Resizing". In addition to the general rule biasing method, resolution enhancement techniques (RET) which includes the inverse lithography technology (ILT) and model based assist feature (MBAF) have been adapted to remove the hot spot and to maximize the process window. If HSP is found during OPC verification stage, various HSF methods can be applied. However, HSF process added on regular OPC procedure makes OPC turn-around time (TAT) increased. In this paper, we introduce a new HSF method that is able to make OPC TAT shorter than the common HSF method. The new HSF method consists of two concepts. The first one is that OPC target point is controlled to fix HSP. Here, the target point should be moved to optimum position at where the edge placement error (EPE) can be 0 at critical points. Many parameters such as a model accuracy or an OPC recipe become the cause of larger EPE. The second one includes controlling of model offset error through target point adjustment. Figure 1 shows the case EPE is not 0. It means that the simulation contour was not targeted well after OPC process. On the other hand, Figure 2 shows the target point is moved -2.5nm by using target point control function. As a result, simulation contour is matched to the original layout. This function can be powerfully adapted to OPC procedure of memory and logic devices.

  3. The timing of control signals underlying fast point-to-point arm movements.

    PubMed

    Ghafouri, M; Feldman, A G

    2001-04-01

    It is known that proprioceptive feedback induces muscle activation when the facilitation of appropriate motoneurons exceeds their threshold. In the suprathreshold range, the muscle-reflex system produces torques depending on the position and velocity of the joint segment(s) that the muscle spans. The static component of the torque-position relationship is referred to as the invariant characteristic (IC). According to the equilibrium-point (EP) hypothesis, control systems produce movements by changing the activation thresholds and thus shifting the IC of the appropriate muscles in joint space. This control process upsets the balance between muscle and external torques at the initial limb configuration and, to regain the balance, the limb is forced to establish a new configuration or, if the movement is prevented, a new level of static torques. Taken together, the joint angles and the muscle torques generated at an equilibrium configuration define a single variable called the EP. Thus by shifting the IC, control systems reset the EP. Muscle activation and movement emerge following the EP resetting because of the natural physical tendency of the system to reach equilibrium. Empirical and simulation studies support the notion that the control IC shifts and the resulting EP shifts underlying fast point-to-point arm movements are gradual rather than step-like. However, controversies exist about the duration of these shifts. Some studies suggest that the IC shifts cease with the movement offset. Other studies propose that the IC shifts end early in comparison to the movement duration (approximately, at peak velocity). The purpose of this study was to evaluate the duration of the IC shifts underlying fast point-to-point arm movements. Subjects made fast (hand peak velocity about 1.3 m/s) planar arm movements toward different targets while grasping a handle. Hand forces applied to the handle and shoulder/elbow torques were, respectively, measured from a force sensor placed

  4. Dynamics and control simulation of the Spacelab Experiment Pointing Mount

    NASA Technical Reports Server (NTRS)

    Marsh, E. L.; Ward, R. S.

    1977-01-01

    Computer simulations were developed to evaluate the performance of four Experiment Pointing Mounts (EPM) being considered for Spacelab experiments in the 1980-1990 time frame. The system modeled compromises a multibody system consisting of the shuttle, a mechanical isolation device, the EPM, celestial and inertial sensors, bearings, gimbal torque motors and associated nonlinearities, the experiment payload, and control and estimator algorithms. Each mount was subjected to a common disturbance (shuttle vernier thruster firing and man push off) and command (stellar pointing or solar raster scan) input. The fundamental limitation common to all mounts was found to be sensor noise. System dynamics and hardware nonlinearities have secondary effects on pointing performance for sufficiently high bandwidth.

  5. Controlling systems that drift through a tipping point

    SciTech Connect

    Nishikawa, Takashi; Ott, Edward

    2014-09-01

    Slow parameter drift is common in many systems (e.g., the amount of greenhouse gases in the terrestrial atmosphere is increasing). In such situations, the attractor on which the system trajectory lies can be destroyed, and the trajectory will then go to another attractor of the system. We consider the case where there are more than one of these possible final attractors, and we ask whether we can control the outcome (i.e., the attractor that ultimately captures the trajectory) using only small controlling perturbations. Specifically, we consider the problem of controlling a noisy system whose parameter slowly drifts through a saddle-node bifurcation taking place on a fractal boundary between the basins of multiple attractors. We show that, when the noise level is low, a small perturbation of size comparable to the noise amplitude applied at a single point in time can ensure that the system will evolve toward a target attracting state with high probability. For a range of noise levels, we find that the minimum size of perturbation required for control is much smaller within a time period that starts some time after the bifurcation, providing a “window of opportunity” for driving the system toward a desirable state. We refer to this procedure as tipping point control.

  6. Control of asteroid retrieval trajectories to libration point orbits

    NASA Astrophysics Data System (ADS)

    Ceriotti, Matteo; Sanchez, Joan Pau

    2016-09-01

    The fascinating idea of shepherding asteroids for science and resource utilization is being considered as a credible concept in a not too distant future. Past studies identified asteroids which could be efficiently injected into manifolds which wind onto periodic orbits around collinear Lagrangian points of the Sun-Earth system. However, the trajectories are unstable, and errors in the capture maneuver would lead to complete mission failure, with potential danger of collision with the Earth, if uncontrolled. This paper investigates the controllability of some asteroids along the transfers and the periodic orbits, assuming the use of a solar-electric low-thrust system shepherding the asteroid. Firstly, an analytical approach is introduced to estimate the stability of the trajectories from a dynamical point of view; then, a numerical control scheme based on a linear quadratic regulator is proposed, where the gains are optimized for each trajectory through a genetic algorithm. A stochastic simulation with a Monte Carlo approach is used to account for different perturbed initial conditions and the epistemic uncertainty on the asteroid mass. Results show that only a small subset of the considered combinations of trajectories/asteroids are reliably controllable, and therefore controllability must be taken into account in the selection of potential targets.

  7. Guaranteeing Pointing Performance of the SDO Sun-Pointing Controllers in Light of Nonlinear Effects

    NASA Technical Reports Server (NTRS)

    Starin, Scott R.; Bourkland, Kristin L.

    2007-01-01

    The Solar Dynamics Observatory (SDO) mission is the first Space Weather Research Network mission, part of NASA s Living With a Star program.1 This program seeks to understand the changing Sun and its effects on the Solar System, life, and society. To this end, the SDO spacecraft will carry three Sun-observing instruments to geosynchronous orbit: Helioseismic and Magnetic Imager (HMI), led by Stanford University; Atmospheric Imaging Assembly (AIA), led by Lockheed Martin Space and Astrophysics Laboratory; and Extreme Ultraviolet Variability Experiment (EVE), led by the University of Colorado. Links describing the instruments in detail may be found through the SDO web site.2 The basic mission goals are to observe the Sun for a very high percentage of the 5-year mission (10-year goal) with long stretches of uninterrupted observations and with constant, high-data-rate transmission to a dedicated ground station. These goals guided the design of the spacecraft bus that will carry and service the three-instrument payload. At the time of this publication, the SDO spacecraft bus is well into the integration and testing phase at the NASA Goddard Space Flight Center (GSFC). A three-axis stabilized attitude control system (ACS) is needed both to point at the Sun accurately and to keep the roll about the Sun vector correctly positioned. The ACS has four reaction wheel modes and 2 thruster actuated modes. More details about the ACS in general and the control modes in particular can be found in Refs. [3-6]. All four of SDO s wheel-actuated control modes involve Sun-pointing controllers, as might be expected from such a mission. Science mode, during which most science data is collected, uses specialized guide telescopes to point accurately at the Sun. Inertial mode has two sub-modes, one tracks a Sun-referenced target orientation, and another maintains an absolute (star-referenced) target orientation, that both employ a Kalman filter to process data from a digital Sun sensor and

  8. Fixed Point Transformations Based Iterative Control of a Polymerization Reaction

    NASA Astrophysics Data System (ADS)

    Tar, József K.; Rudas, Imre J.

    As a paradigm of strongly coupled non-linear multi-variable dynamic systems the mathematical model of the free-radical polymerization of methyl-metachrylate with azobis (isobutyro-nitrile) as an initiator and toluene as a solvent taking place in a jacketed Continuous Stirred Tank Reactor (CSTR) is considered. In the adaptive control of this system only a single input variable is used as the control signal (the process input, i.e. dimensionless volumetric flow rate of the initiator), and a single output variable is observed (the process output, i.e. the number-average molecular weight of the polymer). Simulation examples illustrate that on the basis of a very rough and primitive model consisting of two scalar variables various fixed-point transformations based convergent iterations result in a novel, sophisticated adaptive control.

  9. Vibration control of an active mirror pointing system

    NASA Astrophysics Data System (ADS)

    Su, Joseph C.; Huang, Chien Y.; Austin, Fred; Knowles, Gareth J.

    1993-09-01

    An active vibration control experiment for precision mirror pointing using smart structure is described. The setup consists of a flexible plate clamped to the shaft of an electric motor. Part of the plate is polished to reflect a laser beam whose direction accuracy is the performance criterion. Electroceramic actuators and sensors are incorporated into the plate to control vibration. The analytical model is generated using the ANSYS program. Six flexible modes are kept to investigate the interaction between the rigid and the flexible modes. Three different control strategies were examined. The goal is to suppress the first and the second mode with very little spillover effects from other modes. Simulation results show that the performance objectives can be met. These analytical studies are verified in actual experiments in the near future.

  10. [Critical control points in the pasteurized milk processing fluxogram].

    PubMed

    Lopes, A C; Stamford, T L

    1997-12-01

    With the aim of evaluating the microbiological quality of raw and pasteurized milk and confirm the critical control points in a dairy processing industry (Recife-PE, Brazil), 84 samples of milk were collected from four points of the flow-chart considered critical (raw milk storage tank, outlet of the pasteurizer unit, pasteurized milk storage tank and packing filling machine). All samples were evaluated for the presence of mesophilic and psychotrophics microorganisms. The most probable number (MPN) of total and faecal coliforms were determined. Samples of raw and pasteurized milk (collected from the packing filling machine) were also assessed for the presence of Staphylococcus aureus. The preservation temperature of raw and pasteurized milk in the storage tanks and the MPN of total and faecal coliforms present in the water used by the industry were simultaneously evaluated. High counts of mesophilic and psychotrophics microorganisms, total and faecal coliforms and S. aureus were detect in raw milk production and processing. The pasteurization process reduced the microorganisms to acceptable numbers in the Brazilian standards, however, the statistics analysis showed that the number of microorganisms increased significantly (p < 0.01) in the pasteurized milk storage tank, representing an important point of contamination. The probable reason for this findings was the presence of coliforms in 60% samples of water which was used to clean the milk equipment and the inadequate temperatures in the storage tank. Therefore, the results of the microbiological analysis confirm that the milk maintenance temperature in the storage tanks, the pasteurization and the packaging are critical control points in the pasteurized milk processing fluxogram.

  11. USE OF THE SDO POINTING CONTROLLERS FOR INSTRUMENT CALIBRATION MANEUVERS

    NASA Technical Reports Server (NTRS)

    Vess, Melissa F.; Starin, Scott R.; Morgenstern, Wendy M.

    2005-01-01

    During the science phase of the Solar Dynamics Observatory mission, the three science instruments require periodic instrument calibration maneuvers with a frequency of up to once per month. The command sequences for these maneuvers vary in length from a handful of steps to over 200 steps, and individual steps vary in size from 5 arcsec per step to 22.5 degrees per step. Early in the calibration maneuver development, it was determined that the original attitude sensor complement could not meet the knowledge requirements for the instrument calibration maneuvers in the event of a sensor failure. Because the mission must be single fault tolerant, an attitude determination trade study was undertaken to determine the impact of adding an additional attitude sensor versus developing alternative, potentially complex, methods of performing the maneuvers in the event of a sensor failure. To limit the impact to the science data capture budget, these instrument calibration maneuvers must be performed as quickly as possible while maintaining the tight pointing and knowledge required to obtain valid data during the calibration. To this end, the decision was made to adapt a linear pointing controller by adjusting gains and adding an attitude limiter so that it would be able to slew quickly and still achieve steady pointing once on target. During the analysis of this controller, questions arose about the stability of the controller during slewing maneuvers due to the combination of the integral gain, attitude limit, and actuator saturation. Analysis was performed and a method for disabling the integral action while slewing was incorporated to ensure stability. A high fidelity simulation is used to simulate the various instrument calibration maneuvers.

  12. Extended screening for major mitochondrial DNA point mutations in patients with hereditary hearing loss.

    PubMed

    Kato, Tomofumi; Nishigaki, Yutaka; Noguchi, Yoshihiro; Fuku, Noriyuki; Ito, Taku; Mikami, Eri; Kitamura, Ken; Tanaka, Masashi

    2012-12-01

    Hearing loss (HL) is the most common sensory disorder in humans. Many patients with mitochondrial diseases have sensorineural HL (SNHL). The HL of these patients manifests as a consequence of either syndromic or nonsyndromic mitochondrial diseases. Furthermore, the phenotypes vary among patients even if they are carrying the same mutation. Therefore, these features make it necessary to analyze every presumed mutation in patients with hereditary HL, but the extensive analysis of various mutations is laborious. We analyzed 373 patients with suspected hereditary HL by using an extended suspension-array screening system for major mitochondrial DNA (mtDNA) mutations, which can detect 32 other mtDNA mutations in addition to the previously analyzed 29 mutations. In the present study, we detected 2 different mtDNA mutations among these 373 patients; m.7444G>A in the MT-CO1 gene and m.7472insC in the MT-TS1 gene in 1 patient (0.3%) for each. As these two patients had no clinical features other than HL, they had not been suspected of having mtDNA mutations. This extended screening system together with the previous one is useful for the genetic diagnosis and epidemiological study of both syndromic and nonsyndromic HL.

  13. A Point Mutation in Myh10 Causes Major Defects in Heart Development and Body Wall Closure

    PubMed Central

    Ma, Xuefei; Adelstein, Robert S.

    2014-01-01

    Background The three isoforms of nonmuscle myosin II (NMII-A, NMII-B and NMII-C) play various roles during mouse embryonic development. Previous work, using knockout and hypomorphic mice, showed that MYH10 encoding myosin heavy chain II-B is critical for cardiac and brain development. Ablating or decreasing NMII-B by 80% results in cardiac (ventricular septal defect, double outlet of the right ventricle) and brain defects but not midline fusion defects. Neither NMII-A nor II-C appear to play roles in early myocardial development. Methods and Results We had previously generated point mutant knock-in mice and now report novel findings due to expressing motor deficient NMII-B at wild-type levels. Homozygous mice die at E14.5 in cardiac failure exhibiting abnormalities not seen in NMII-B null and hypomorphic mice: a failure in midline fusion resulting in a cleft palate, ectopia cordis, and a large omphalocele. Fusion of the sternum and endocardial cushions is impaired in the mutant mice associated with a failure in apoptosis of the mesenchyme cells. Failure to disassemble myocyte cell-cell adhesions during cardiac outflow tract development contributes to impaired outflow tract myocardialization and displacement of the aorta to the right ventricle. Conclusions Expression of motor impaired NMII-B disrupts normal ventral body wall closure, due to a dominant negative effect. This is not due to the loss of NMII-B function but rather to a gain-of-function resulting from prolonged crosslinking of NMII-B to actin-filaments thereby interfering with the dynamics of actomyosin cytoskeletal structure. Moreover impaired NMII-B motor activity inhibits outflow tract myocardialization leading to mis-localization of the aorta. PMID:24825879

  14. Pointing Control System for a High Precision Flight Telescope

    SciTech Connect

    BENTLEY,ANTHONY E.; WILCOXEN,JEFFREY LEE

    2000-12-01

    A pointing control system is developed and tested for a flying gimbaled telescope. The two-axis pointing system is capable of sub-microradian pointing stability and high accuracy in the presence of large host vehicle jitter. The telescope also has high agility--it is capable of a 50-degree retarget (in both axes simultaneously) in less than 2 seconds. To achieve the design specifications, high-accuracy, high-resolution, two-speed resolvers were used, resulting in gimbal-angle measurements stable to 1.5 microradians. In addition, on-axis inertial angle displacement sensors were mounted on the telescope to provide host-vehicle jitter cancellation. The inertial angle sensors are accurate to about 100 nanoradians, but do not measure low frequency displacements below 2 Hz. The gimbal command signal includes host-vehicle attitude information, which is band-limited. This provides jitter data below 20 Hz, but includes a variable latency between 15 and 25 milliseconds. One of the most challenging aspects of this design was to combine the inertial-angle-sensor data with the less perfect information in the command signal to achieve maximum jitter reduction. The optimum blending of these two signals, along with the feedback compensation were designed using Quantitative Feedback Theory.

  15. Floating-point system quantization errors in digital control systems

    NASA Technical Reports Server (NTRS)

    Phillips, C. L.

    1973-01-01

    The results are reported of research into the effects on system operation of signal quantization in a digital control system. The investigation considered digital controllers (filters) operating in floating-point arithmetic in either open-loop or closed-loop systems. An error analysis technique is developed, and is implemented by a digital computer program that is based on a digital simulation of the system. As an output the program gives the programing form required for minimum system quantization errors (either maximum of rms errors), and the maximum and rms errors that appear in the system output for a given bit configuration. The program can be integrated into existing digital simulations of a system.

  16. Pointing Control System Architecture for the Eclipse Mission

    NASA Technical Reports Server (NTRS)

    Kia, Tooraj; Brugarolas, Paul B.; Alexander, James W.; Li, Diane G.

    2006-01-01

    This paper describes the high performance pointing control system used to point the Eclipse telescope. Eclipse is a new mission under study at Jet Propulsion Laboratory for a proposal as a discovery mission. Eclipse is a space telescope for high-contrast optical astronomy. It will be used to investigate the planetary bodies and environments. The main objective of the Eclipse mission is to study planets around nearby stars. Eclipse is designed to reveal planets or dust structures by reducing the scattered and diffracted light within a few arcseconds of a star to a level three orders of magnitude lower than any instrument on the Hubble Space Telescope (HST). Eclipse achieves this high contrast using a 1.8 meter diameter telescope, a coronagraphic system for control of diffracted light, and active wavefront correction using a Precision Deformable Mirror (DM) for the suppression of scattered light. The observatory will be launched into a Sun-synchronous 690 Km, 98.2(deg) Earth Orbit in 2012.

  17. Identifying and characterizing major emission point sources as a basis for geospatial distribution of mercury emissions inventories

    NASA Astrophysics Data System (ADS)

    Steenhuisen, Frits; Wilson, Simon J.

    2015-07-01

    Mercury is a global pollutant that poses threats to ecosystem and human health. Due to its global transport, mercury contamination is found in regions of the Earth that are remote from major emissions areas, including the Polar regions. Global anthropogenic emission inventories identify important sectors and industries responsible for emissions at a national level; however, to be useful for air transport modelling, more precise information on the locations of emission is required. This paper describes the methodology applied, and the results of work that was conducted to assign anthropogenic mercury emissions to point sources as part of geospatial mapping of the 2010 global anthropogenic mercury emissions inventory prepared by AMAP/UNEP. Major point-source emission sectors addressed in this work account for about 850 tonnes of the emissions included in the 2010 inventory. This work allocated more than 90% of these emissions to some 4600 identified point source locations, including significantly more point source locations in Africa, Asia, Australia and South America than had been identified during previous work to geospatially-distribute the 2005 global inventory. The results demonstrate the utility and the limitations of using existing, mainly public domain resources to accomplish this work. Assumptions necessary to make use of selected online resources are discussed, as are artefacts that can arise when these assumptions are applied to assign (national-sector) emissions estimates to point sources in various countries and regions. Notwithstanding the limitations of the available information, the value of this procedure over alternative methods commonly used to geo-spatially distribute emissions, such as use of 'proxy' datasets to represent emissions patterns, is illustrated. Improvements in information that would facilitate greater use of these methods in future work to assign emissions to point-sources are discussed. These include improvements to both national

  18. Nonlinear Burn Control and Operating Point Optimization in ITER

    NASA Astrophysics Data System (ADS)

    Boyer, Mark; Schuster, Eugenio

    2013-10-01

    Control of the fusion power through regulation of the plasma density and temperature will be essential for achieving and maintaining desired operating points in fusion reactors and burning plasma experiments like ITER. In this work, a volume averaged model for the evolution of the density of energy, deuterium and tritium fuel ions, alpha-particles, and impurity ions is used to synthesize a multi-input multi-output nonlinear feedback controller for stabilizing and modulating the burn condition. Adaptive control techniques are used to account for uncertainty in model parameters, including particle confinement times and recycling rates. The control approach makes use of the different possible methods for altering the fusion power, including adjusting the temperature through auxiliary heating, modulating the density and isotopic mix through fueling, and altering the impurity density through impurity injection. Furthermore, a model-based optimization scheme is proposed to drive the system as close as possible to desired fusion power and temperature references. Constraints are considered in the optimization scheme to ensure that, for example, density and beta limits are avoided, and that optimal operation is achieved even when actuators reach saturation. Supported by the NSF CAREER award program (ECCS-0645086).

  19. Critical limits for the control points for halal poultry slaughter.

    PubMed

    Shahdan, Intan Azura; Regenstein, Joe Mac; Rahman, Mohammad Tariqur

    2016-12-13

    This study proposes critical limits (CL) for control points for halal slaughter (CPHS). Previously, 6 control points (CP) were determined, and CL for these 6 CPHS are suggested based on: 1) a literature survey for the CL for CP 1 (poultry breeding, rearing, and poultry feed) and CP 2 (welfare of poultry during transportation and lairage); 2) a field survey of slaughter plants in Kuantan (Malaysia) for CP 3 (immobilization), CP 4 (slaughter), CP 5 (time for full bleed-out), and CP 6 (washing and packaging); and 3) controlled experiments to refine the CL for CP 3, 4, and 5. The CL for CP 1 focused on stress reduction during rearing and use of substances that could compromise poultry meat wholesomeness. The CL for CP 2 emphasizes humane best-practices for handling poultry during lairage. The CL for CP 3 suggests a gap of 5 s between 2 shackles if only one shackler is employed and shackling times of <1 min for live chickens. In countries permitting water-bath electrical stunning of halal poultry, the stunning current needed to induce unconsciousness must be defined for the breed and bird size but not cause any chicken deaths. The CL for CP 4 mandates the recitation of the tasmiyah (the invocation), which if done for every chicken, will require ≥5 s between stunning and neck cutting. The CL for CP 4 also includes information about the slaughter knife. In CP 5 the recommended minimum time between neck cutting and scalding is 9.5 min. Finally, the CL for CP 6 emphasizes good supply chain hygiene and zero adulteration from haram species and substances.

  20. Developing control points for halal slaughtering of poultry.

    PubMed

    Shahdan, I A; Regenstein, J M; Shahabuddin, A S M; Rahman, M T

    2016-07-01

    Halal (permissible or lawful) poultry meat production must meet industry, economic, and production needs, and government health requirements without compromising the Islamic religious requirements derived from the Qur'an and the Hadiths (the actions and sayings of the Prophet Muhammad, peace and blessings be upon him). Halal certification authorities may vary in their interpretation of these teachings, which leads to differences in halal slaughter requirements. The current study proposes 6 control points (CP) for halal poultry meat production based on the most commonly used halal production systems. CP 1 describes what is allowed and prohibited, such as blood and animal manure, and feed ingredients for halal poultry meat production. CP 2 describes the requirements for humane handling during lairage. CP 3 describes different methods for immobilizing poultry, when immobilization is used, such as water bath stunning. CP 4 describes the importance of intention, details of the halal slaughter, and the equipment permitted. CP 5 and CP 6 describe the requirements after the neck cut has been made such as the time needed before the carcasses can enter the scalding tank, and the potential for meat adulteration with fecal residues and blood. It is important to note that the proposed halal CP program is presented as a starting point for any individual halal certifying body to improve its practices.

  1. G proteins: critical control points for transmembrane signals.

    PubMed Central

    Neer, E. J.

    1994-01-01

    Heterotrimeric GTP-binding proteins (G proteins) that are made up of alpha and beta gamma subunits couple many kinds of cell-surface receptors to intracellular effector enzymes or ion channels. Every cell contains several types of receptors, G proteins, and effectors. The specificity with which G protein subunits interact with receptors and effectors defines the range of responses a cell is able to make to an external signal. Thus, the G proteins act as a critical control point that determines whether a signal spreads through several pathways or is focused to a single pathway. In this review, I will summarize some features of the structure and function of mammalian G protein subunits, discuss the role of both alpha and beta gamma subunits in regulation of effectors, the role of the beta gamma subunit in macromolecular assembly, and the mechanisms that might make some responses extremely specific and others rather diffuse. PMID:8142895

  2. The Galileo scan platform pointing control system - A modern control theoretic viewpoint

    NASA Technical Reports Server (NTRS)

    Sevaston, G. E.; Macala, G. A.; Man, G. K.

    1985-01-01

    The current Galileo scan platform pointing control system (SPPCS) is described, and ways in which modern control concepts could serve to enhance it are considered. Of particular interest are: the multi-variable design model and overall control system architecture, command input filtering, feedback compensator and command input design, stability robustness constraint for both continuous time control systems and for sampled data control systems, and digital implementation of the control system. The proposed approach leads to the design of a system that is similar to current Galileo SPPCS configuration, but promises to be more systematic.

  3. Using bioluminescent biosensors for hazard analysis and critical control point (HACCP) in wastewater control.

    PubMed

    Valat, C; Champiat, D; Degorce-Dumas, J R; Thomas, O

    2004-01-01

    Starting from a new approach for water pollution control and wastewater treatment plant management, the hazard analysis and critical control point (HACCP) quality concept, the interest for the development of new rapid and sensitive methods such as bioluminescence-based methods is evident. After an introduction of the HACCP procedure, a bibliographic study of the bioluminescence potentiality is presented and discussed.

  4. Sliding control of pointing and tracking with operator spline estimation

    NASA Technical Reports Server (NTRS)

    Dwyer, Thomas A. W., III; Fakhreddine, Karray; Kim, Jinho

    1989-01-01

    It is shown how a variable structure control technique could be implemented to achieve precise pointing and good tracking of a deformable structure subject to fast slewing maneuvers. The correction torque that has to be applied to the structure is based on estimates of upper bounds on the model errors. For a rapid rotation of the deformable structure, the elastic response can be modeled by oscillators driven by angular acceleration, and where stiffness and damping coefficients are also angular velocity and acceleration dependent. By transforming this slew-driven elastic dynamics into bilinear form (be regarding the vector made up of the angular velocity, squared angular velocity and angular acceleration components, which appear in the coefficients as the input to the deformation dynamics), an operator spline can be constructed, that gives a low order estimate of the induced disturbance. Moreover, a worst case error bound between the estimated deformation and the unknown exact deformation is also generated, which can be used where required in the sliding control correction.

  5. MSL EDL Entry Guidance using the Entry Terminal Point Controller

    NASA Technical Reports Server (NTRS)

    2006-01-01

    The Mars Science Laboratory will be the first Mars mission to attempt a guided entry with the objective of safely delivering the entry vehicle to a survivable parachute deploy state within 10 km of the pre-designated landing site. The Entry Terminal Point Controller guidance algorithm is derived from the final phase Apollo Command Module guidance and, like Apollo, modulates the bank angle to control range based on deviations in range, altitude rate, and drag acceleration from a reference trajectory. For application to Mars landers which must make use of the tenuous Martian atmosphere, it is critical to balance the lift of the vehicle to minimize the range while still ensuring a safe deploy altitude. An overview of the process to generate optimized guidance settings is presented, discussing improvements made over the last four years. Performance tradeoffs between ellipse size and deploy altitude will be presented, along with imposed constraints of entry acceleration and heating. Performance sensitivities to the bank reversal deadbands, heading alignment, attitude initialization error, and atmospheric delivery errors are presented. Guidance settings for contingency operations, such as those appropriate for severe dust storm scenarios, are evaluated.

  6. Pointing control system design and performance evaluation of TPF coronagraph

    NASA Astrophysics Data System (ADS)

    Liu, Kuo-Chia; Blaurock, Carl; Mosier, Gary E.

    2004-09-01

    The Terrestrial Planet Finder (TPF) project aims to detect and characterize extra-solar Earth-like planets. The coronagraph telescope is one of the two mission concepts being studied. To reject the star flux and detect the planet flux in the visible light range, the coronagraph telescope must achieve a rejection ratio on the order of a billion to one. Dynamic jitter, introduced by environmental and on-board mechanical disturbances, degrades the optical performance, as characterized primarily by contrast ratio. The feasibility of using passive vibration isolation combined with active attitude and line-of-sight (LOS) control systems to stabilize the spacecraft and the optical components to the requisite level is being studied. The telescope is also required to slew between targets or rotate around the LOS. The slew mode control law must be designed to balance the need for efficient large-angle maneuvers while simultaneously avoiding the excitation of flexible modes in order to minimize settling time. This paper provides an overview of the current control design concept and sensor/actuator topology for TPF Coronagraph and illustrates the fine pointing performance of the telescope. This performance is primarily a function of the rejection of high-frequency dynamic disturbances, in this case due to reaction wheel disturbance forces/torques transmitted through the passive isolation stage. Trade studies between isolator force rejection and disturbance level reduction via wheel redesign are also presented to illustrate the requirements imposed on current technologies. Finally, the paper summarizes preliminary results on the slew/settle performance of the telescope.

  7. Optimal fine pointing control of a large space telescope using an Annular Momentum Control Device

    NASA Technical Reports Server (NTRS)

    Nadkarni, A. A.; Joshi, S. M.; Groom, N. J.

    1977-01-01

    This paper discusses the application of an Annular Momentum Control Device (AMCD) to fine pointing control of a large space telescope (LST). The AMCD represents a new development in the field of momentum storage devices. A linearized mathematical model is developed for the AMCD/LST system, including the magnetic suspension actuators. Two approaches to control system design are considered. The first approach uses a stochastic linear-quadratic Gaussian controller which utilizes feedback of all states. The second approach considers a more practical control system design in which the axial and radial loops are designed independently.

  8. [Spatial heterogeneity and classified control of agricultural non-point source pollution in Huaihe River Basin].

    PubMed

    Zhou, Liang; Xu, Jian-Gang; Sun, Dong-Qi; Ni, Tian-Hua

    2013-02-01

    Agricultural non-point source pollution is of importance in river deterioration. Thus identifying and concentrated controlling the key source-areas are the most effective approaches for non-point source pollution control. This study adopts inventory method to analysis four kinds of pollution sources and their emissions intensity of the chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) in 173 counties (cities, districts) in Huaihe River Basin. The four pollution sources include livestock breeding, rural life, farmland cultivation, aquacultures. The paper mainly addresses identification of non-point polluted sensitivity areas, key pollution sources and its spatial distribution characteristics through cluster, sensitivity evaluation and spatial analysis. A geographic information system (GIS) and SPSS were used to carry out this study. The results show that: the COD, TN and TP emissions of agricultural non-point sources were 206.74 x 10(4) t, 66.49 x 10(4) t, 8.74 x 10(4) t separately in Huaihe River Basin in 2009; the emission intensity were 7.69, 2.47, 0.32 t.hm-2; the proportions of COD, TN, TP emissions were 73%, 24%, 3%. The paper achieves that: the major pollution source of COD, TN and TP was livestock breeding and rural life; the sensitivity areas and priority pollution control areas among the river basin of non-point source pollution are some sub-basins of the upper branches in Huaihe River, such as Shahe River, Yinghe River, Beiru River, Jialu River and Qingyi River; livestock breeding is the key pollution source in the priority pollution control areas. Finally, the paper concludes that pollution type of rural life has the highest pollution contribution rate, while comprehensive pollution is one type which is hard to control.

  9. 46 CFR 153.297 - Emergency actuators at the point of cargo control.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of cargo control. (a) The point from which cargo transfer is controlled must have the same actuators... 46 Shipping 5 2011-10-01 2011-10-01 false Emergency actuators at the point of cargo control. 153... systems required by this part. (b) The point from which cargo transfer is controlled may be one of...

  10. 49 CFR 236.103 - Switch circuit controller or point detector.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Switch circuit controller or point detector. 236... Rules and Instructions: All Systems Inspections and Tests; All Systems § 236.103 Switch circuit controller or point detector. Switch circuit controller, circuit controller, or point detector operated...

  11. 49 CFR 236.103 - Switch circuit controller or point detector.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Switch circuit controller or point detector. 236... Rules and Instructions: All Systems Inspections and Tests; All Systems § 236.103 Switch circuit controller or point detector. Switch circuit controller, circuit controller, or point detector operated...

  12. 49 CFR 236.103 - Switch circuit controller or point detector.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Switch circuit controller or point detector. 236... Rules and Instructions: All Systems Inspections and Tests; All Systems § 236.103 Switch circuit controller or point detector. Switch circuit controller, circuit controller, or point detector operated...

  13. 49 CFR 236.103 - Switch circuit controller or point detector.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Switch circuit controller or point detector. 236... Rules and Instructions: All Systems Inspections and Tests; All Systems § 236.103 Switch circuit controller or point detector. Switch circuit controller, circuit controller, or point detector operated...

  14. 49 CFR 236.103 - Switch circuit controller or point detector.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Switch circuit controller or point detector. 236... Rules and Instructions: All Systems Inspections and Tests; All Systems § 236.103 Switch circuit controller or point detector. Switch circuit controller, circuit controller, or point detector operated...

  15. Adaptive Control for Buck Power Converter Using Fixed Point Inducting Control and Zero Average Dynamics Strategies

    NASA Astrophysics Data System (ADS)

    Hoyos Velasco, Fredy Edimer; García, Nicolás Toro; Garcés Gómez, Yeison Alberto

    In this paper, the output voltage of a buck power converter is controlled by means of a quasi-sliding scheme. The Fixed Point Inducting Control (FPIC) technique is used for the control design, based on the Zero Average Dynamics (ZAD) strategy, including load estimation by means of the Least Mean Squares (LMS) method. The control scheme is tested in a Rapid Control Prototyping (RCP) system based on Digital Signal Processing (DSP) for dSPACE platform. The closed loop system shows adequate performance. The experimental and simulation results match. The main contribution of this paper is to introduce the load estimator by means of LMS, to make ZAD and FPIC control feasible in load variation conditions. In addition, comparison results for controlled buck converter with SMC, PID and ZAD-FPIC control techniques are shown.

  16. Effective variable switching point predictive current control for ac low-voltage drives

    NASA Astrophysics Data System (ADS)

    Stolze, Peter; Karamanakos, Petros; Kennel, Ralph; Manias, Stefanos; Endisch, Christian

    2015-07-01

    This paper presents an effective model predictive current control scheme for induction machines driven by a three-level neutral point clamped inverter, called variable switching point predictive current control. Despite the fact that direct, enumeration-based model predictive control (MPC) strategies are very popular in the field of power electronics due to their numerous advantages such as design simplicity and straightforward implementation procedure, they carry two major drawbacks. These are the increased computational effort and the high ripples on the controlled variables, resulting in a limited applicability of such methods. The high ripples occur because in direct MPC algorithms the actuating variable can only be changed at the beginning of a sampling interval. A possible remedy for this would be to change the applied control input within the sampling interval, and thus to apply it for a shorter time than one sample. However, since such a solution would lead to an additional overhead which is crucial especially for multilevel inverters, a heuristic preselection of the optimal control action is adopted to keep the computational complexity at bay. Experimental results are provided to verify the potential advantages of the proposed strategy.

  17. Major enzymes controlling the androgenic pressure in the developing lung.

    PubMed

    Tremblay, Yves; Provost, Pierre R

    2013-09-01

    A sex difference is observed in the incidence and morbidity of respiratory distress syndrome (RDS) of the neonate and in bronchopulmonary dysplasia (BPD). The involvement of androgens is well evidenced in RDS and it is suspected in BPD. Interestingly, the developing lung is not an inert tissue just exposed to circulating androgens, but is rather an active androgen metabolizing tissue, expressing enzymes involved in both androgen synthesis and inactivation. The present review focuses on the major enzymes involved in androgen metabolism within the developing lung. Testosterone synthesis and inactivation by AKR1C3/Akr1c6 (human/mouse 17β-hydroxysteroid dehydrogenases (HSDs) type 5) and HSD17B2 (17β-HSD type 2), respectively, play an important role in the developing lung. Akr1c14 (3α-HSD) shows a strong increase in expression according to developmental time. The canalicular stage of lung development corresponding to the surge of surfactant lipid synthesis, which is linked to RDS, as well as saccularization/alveolarization, which are linked to BPD, are covered by this review for the mouse and human species. The androgen metabolizing enzymes expressed within the developing lung can become potential pharmaceutical targets in the objective of accelerating lung maturation by specific treatments. The classic deleterious effects of androgens on lung maturation and the surge of surfactant synthesis in males are well known. Conversely, androgens also have positive impacts on the development of both male and female lungs. Steroidogenic enzymes are key regulators of these positive effects. This article is part of a Special Issue entitled 'CSR 2013'.

  18. Upstream Pathways Controlling Mitochondrial Function in Major Psychosis

    PubMed Central

    Machado, Alencar Kolinski; Pan, Alexander Yongshuai; da Silva, Tatiane Morgana; Duong, Angela

    2016-01-01

    Mitochondrial dysfunction is commonly observed in bipolar disorder (BD) and schizophrenia (SCZ) and may be a central feature of psychosis. These illnesses are complex and heterogeneous, which is reflected by the complexity of the processes regulating mitochondrial function. Mitochondria are typically associated with energy production; however, dysfunction of mitochondria affects not only energy production but also vital cellular processes, including the formation of reactive oxygen species, cell cycle and survival, intracellular Ca2+ homeostasis, and neurotransmission. In this review, we characterize the upstream components controlling mitochondrial function, including 1) mutations in nuclear and mitochondrial DNA, 2) mitochondrial dynamics, and 3) intracellular Ca2+ homeostasis. Characterizing and understanding the upstream factors that regulate mitochondrial function is essential to understand progression of these illnesses and develop biomarkers and therapeutics. PMID:27310240

  19. 46 CFR 153.297 - Emergency actuators at the point of cargo control.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Emergency actuators at the point of cargo control. 153... and Equipment Piping Systems and Cargo Handling Equipment § 153.297 Emergency actuators at the point of cargo control. (a) The point from which cargo transfer is controlled must have the same...

  20. 21 CFR 120.8 - Hazard Analysis and Critical Control Point (HACCP) plan.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Hazard Analysis and Critical Control Point (HACCP... SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION HAZARD ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS General Provisions § 120.8 Hazard Analysis and Critical Control Point (HACCP) plan. (a) HACCP plan....

  1. Instrument Pointing Control System for the Stellar Interferometry Mission - Planet Quest

    NASA Technical Reports Server (NTRS)

    Brugarolas, Paul B.; Kang, Bryan

    2006-01-01

    This paper describes the high precision Instrument Pointing Control System (PCS) for the Stellar Interferometry Mission (SIM) - Planet Quest. The PCS system provides front-end pointing, compensation for spacecraft motion, and feedforward stabilization, which are needed for proper interference. Optical interferometric measurements require very precise pointing (0.03 as, 1-(sigma) radial) for maximizing the interference pattern visibility. This requirement is achieved by fine pointing control of articulating pointing mirrors with feedback from angle tracking cameras. The overall pointing system design concept is presentcd. Functional requirements and an acquisition concept are given. Guide and Science pointing control loops are discussed. Simulation analyses demonstrate the feasibility of the design.

  2. Pointing and control system design study for the space infrared telescope facility (SIRTF)

    NASA Technical Reports Server (NTRS)

    Lorell, K. R.; Aubrun, J. N.; Sridhar, B.; Cochran, R. W.

    1984-01-01

    The design and performance of pointing and control systems for two space infrared telescope facility vehicles were examined. The need for active compensation of image jitter using the secondary mirror or other optical elements was determined. In addition, a control system to allow the telescope to perform small angle slews, and to accomplish large angle slews at the rate of 15 deg per minute was designed. Both the 98 deg and the 28 deg inclination orbits were examined, and spacecraft designs were developed for each. The results indicate that active optical compensation of line-of-sight errors is not necessary if the system is allowed to settle for roughly ten seconds after a slew maneuver. The results are contingent on the assumption of rigid body dynamics, and a single structural mode between spacecraft and telescope. Helium slosh for a half full 4000 liter tank was analyzed, and did not represent a major control problem.

  3. A test of fixed and moving reference point control in posture.

    PubMed

    Lee, I-Chieh; Pacheco, Matheus M; Newell, Karl M

    2017-01-01

    This study investigated two contrasting assumptions of the regulation of posture: namely, fixed and moving reference point control. These assumptions were tested in terms of time-dependent structure and data distribution properties when stability is manipulated. Fifteen male participants performed a tightrope simulated balance task that is, maintaining a tandem stance while holding a pole. Pole length (and mass) and the standing support surface (fixed surface/balance board) were manipulated so as to mechanically change the balance stability. The mean and standard deviation (SD) of COP length were reduced with pole length increment but only in the balance board surface condition. Also, the SampEn was lower with greater pole length for the balance board but not the fixed surface. More than one peak was present in the distribution of COP in the majority of trials. Collectively, the findings provide evidence for a moving reference point in the maintenance of postural stability for quiet standing.

  4. Major safety and operational concerns for fuel debris criticality control

    SciTech Connect

    Tonoike, K.; Sono, H.; Umeda, M.; Yamane, Y.; Kugo, T.; Suyama, K.

    2013-07-01

    It can be seen from the criticality control viewpoint that the requirement divides the decommissioning work into two parts. One is the present condition where it is requested to prevent criticality and to monitor subcritical condition while the debris is untouched. The other is future work where the subcritical condition shall be ensured even if the debris condition is changed intentionally by raising water level, debris retrieval, etc. Repair of damages on the containment vessel (CV) walls is one of the most important objectives at present in the site. On completion of this task, it will become possible to raise water levels in the CVs and to shield the extremely high radiation emitted from the debris but there is a dilemma: raising the water level in the CVs implies to bring the debris closer to criticality because of the role of water for slowing down neutrons. This may be solved if the coolant water will start circulating in closed loops, and if a sufficient concentration of soluble neutron poison (borated water for instance) will be introduced in the loop. It should be still noted that this solution has a risk of worsening corrosion of the CV walls. Design of the retrieval operation of debris should be proposed as early as possible, which must include a neutron poison concentration required to ensure that the debris chunk is subcritical. In parallel, the development of the measurement system to monitor subcritical condition of the debris chunk should be conducted in case the borated water cannot be used continuously. The system would be based on a neutron counter with a high sensitivity and an appropriate shield for gamma-rays, and the adequate statistical signal processing.

  5. Resilience of Greek Youth at an Educational Transition Point: The Role of Locus of Control and Coping Strategies as Resources

    ERIC Educational Resources Information Center

    Leontopoulou, Sophia

    2006-01-01

    Variable--and person--focused approaches were applied to study the resilient outcomes of 326 Greek male and female 1st year university students at a major educational transition point. Results indicated that resilience was related to both cognitive and behavioural psychosocial resources in late adolescence. Locus of control emerged as an important…

  6. Multi-Interface Point-To-Point Switching System (MIPPSS) Under Unified Control

    DTIC Science & Technology

    1998-09-18

    signaled in a digital circuit by varying voltages. The most common digital logic, transistor-transistor logic ( TTL ), uses +0.5 volts nominal for a low...types of ports, i.e., four Ethernet ports and up to five RS232 ports, advantageously are included in the HUB Controller Cage 23, which is discussed in...one time. The Ethernet and RS232 limits are the maximum number of physical ports of these devices that are available on the HUB Controller. The

  7. Formation Flying With Decentralized Control in Libration Point Orbits

    NASA Technical Reports Server (NTRS)

    Folta, David; Carpenter, J. Russell; Wagner, Christoph

    2000-01-01

    A decentralized control framework is investigated for applicability of formation flying control in libration orbits. The decentralized approach, being non-hierarchical, processes only direct measurement data, in parallel with the other spacecraft. Control is accomplished via linearization about a reference libration orbit with standard control using a Linear Quadratic Regulator (LQR) or the GSFC control algorithm. Both are linearized about the current state estimate as with the extended Kalman filter. Based on this preliminary work, the decentralized approach appears to be feasible for upcoming libration missions using distributed spacecraft.

  8. 49 CFR 236.303 - Control circuits for signals, selection through circuit controller operated by switch points or...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... circuit controller operated by switch points or by switch locking mechanism. 236.303 Section 236.303... § 236.303 Control circuits for signals, selection through circuit controller operated by switch points or by switch locking mechanism. The control circuit for each aspect with indication more...

  9. 49 CFR 236.303 - Control circuits for signals, selection through circuit controller operated by switch points or...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... circuit controller operated by switch points or by switch locking mechanism. 236.303 Section 236.303... § 236.303 Control circuits for signals, selection through circuit controller operated by switch points or by switch locking mechanism. The control circuit for each aspect with indication more...

  10. Escitalopram versus paroxetine controlled release in major depressive disorder: a randomized trial

    PubMed Central

    Kishi, Taro; Matsuda, Yuki; Matsunaga, Shinji; Moriwaki, Masatsugu; Otake, Yoichiro; Akamatsu, Kaku; Okochi, Tomo; Hirano, Shigeki; Funahashi, Toshihiko; Okuda, Momoko; Tabuse, Hideaki; Fujita, Kiyoshi; Iwata, Nakao

    2017-01-01

    Objective There are no direct comparisons between escitalopram and paroxetine controlled release in patients with major depressive disorder (MDD). Methods We conducted a 24-week, rater-masked, randomized trial of escitalopram (5–20 mg/day) versus paroxetine controlled release (12.5–50 mg/day) in patients with MDD (UMIN000011191). Patients with the diagnosis of moderate-to-severe MDD (a 17-item Hamilton Rating Scale for Depression [HAMD-17], with total score at baseline being ≥20) were recruited to participate in a parallel, randomized, controlled trial. The primary outcome for efficacy was an improvement in the 21-item HAMD (HAMD-21) total score at 24 weeks. The secondary outcomes were the response, remission, and discontinuation rates and the incidence of individual adverse events. Results A total of 88 patients with MDD (males, 61.4%; mean age, 40.8±13.4 years) were recruited. The discontinuation rate was 58.0% (escitalopram, 55.8%; paroxetine controlled release, 60.0%). Both escitalopram and paroxetine controlled-release treatment groups exhibited significant reduction in the HAMD-21 total score at 2, 4, 8, 12, and 24 weeks from the baseline. However, there were no significant differences in the HAMD-21 total score, response rate, remission rate, and discontinuation rate at any time point between the groups. In addition, there were no significant differences in the incidence of any individual adverse events (eg, nausea, vomiting, and somnolence) between the treatment groups. Conclusion Our results suggest that escitalopram and paroxetine controlled release had similar efficacy and safety profiles in patients with MDD. One of the primary limitations of this study is the small sample size. PMID:28123299

  11. Digital controller design: Analysis of the annular suspension pointing system. [analog controllers with feedback

    NASA Technical Reports Server (NTRS)

    Kuo, B. C.

    1978-01-01

    The analog controllers of the annular suspension pointing system are designed for control of the chi, phi sub 1, and phi sub 2 bandwidth dynamics through decoupling and pole placement. Since it is virtually impossible to find an equivalent bandwidth of the overall system and establish a general eigenvalue requirement for the system, the subsystem dynamics are decoupled through state feedback and the poles are placed simultaneously to realize the desired bandwidths for the three system components. Decoupling and pole placement are also used to design the closed-loop digital system through approximation.

  12. 49 CFR 236.303 - Control circuits for signals, selection through circuit controller operated by switch points or...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-point frogs and derails shall be selected through circuit controller operated directly by switch points... switch, movable-point frog, and derail in the routes governed by such signal. Circuits shall be arranged... when each switch, movable-point frog, and derail in the route is in proper position....

  13. 49 CFR 236.303 - Control circuits for signals, selection through circuit controller operated by switch points or...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-point frogs and derails shall be selected through circuit controller operated directly by switch points... switch, movable-point frog, and derail in the routes governed by such signal. Circuits shall be arranged... when each switch, movable-point frog, and derail in the route is in proper position....

  14. 49 CFR 236.303 - Control circuits for signals, selection through circuit controller operated by switch points or...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-point frogs and derails shall be selected through circuit controller operated directly by switch points... switch, movable-point frog, and derail in the routes governed by such signal. Circuits shall be arranged... when each switch, movable-point frog, and derail in the route is in proper position....

  15. Autonomous-Control Concept For Instrument Pointing System

    NASA Technical Reports Server (NTRS)

    Mettler, Edward; Milman, Mark H.; Bayard, David S.

    1990-01-01

    Integrated payload articulation and identification system (IPAIDS) is conceptual system to control aiming of instruments aboard spacecraft of proposed Earth Observation System (EOS). Principal features of concept include advanced control strategies intended to assure robustness of performance over wide range of uncertainties in characteristics of spacecraft and instrument system. Intended originally for application to spacecraft system, has potential utility on Earth for automatic control of autonomous (robotic) vehicles or of remote sensing systems.

  16. Anatomy of an experimental two-link flexible manipulator under end-point control

    NASA Technical Reports Server (NTRS)

    Oakley, Celia M.; Cannon, Robert H., Jr.

    1990-01-01

    The design and experimental implementation of an end-point controller for two-link flexible manipulators are presented. The end-point controller is based on linear quadratic Gaussian (LQG) theory and is shown to exhibit significant improvements in trajectory tracking over a conventional controller design. To understand the behavior of the manipulator structure under end-point control, a strobe sequence illustrating the link deflections during a typical slew maneuver is included.

  17. Towards a controlled study of the QCD critical point

    NASA Astrophysics Data System (ADS)

    de Forcrand, Ph; Philipsen, O.

    2008-10-01

    The phase diagram of QCD, as a function of temperature T and quark chemical potential μ, may contain a critical point (μE, TE) whose non-perturbative nature makes it a natural object of lattice studies. However, the sign problem prevents the application of standard Monte Carlo techniques at nonzero baryon density. We have been pursuing an approach free of the sign problem, where the chemical potential is taken as imaginary and the results are Taylor expanded in μ/T about μ = 0, then analytically continued to real μ. Within this approach we have determined the sensitivity of the critical chemical potential μE to the quark mass, d(\\mu_E)^2/dm_q|_{\\mu_E=0} . Our study indicates that the critical point moves to a larger chemical potential as the quark mass decreases. This finding, contrary to common wisdom, implies that the deconfinement crossover, which takes place in QCD at μ = 0 when the temperature is raised, will remain a crossover in the μ-region where our Taylor expansion can be trusted. If this result, obtained on a coarse lattice, is confirmed by simulations on finer lattices now in progress, then we predict that no chiral critical point will be found for μB lsim 500 MeV, unless the phase diagram contains additional transitions.

  18. The Validity of the SAT® for Predicting Cumulative Grade Point Average by College Major. Research Report 2012-6

    ERIC Educational Resources Information Center

    Shaw, Emily J.; Kobrin, Jennifer L.; Patterson, Brian F.; Mattern, Krista D.

    2012-01-01

    The current study examined the differential validity of the SAT for predicting cumulative GPA (cGPA) through the second year of college by college major, as well as the differential prediction of cGPA by college major across student subgroups. The relationship between the SAT and cGPA varied somewhat by major, as well as by major and subgroup…

  19. a Libration Model for Enceladus Based on Geodetic Control Point Network Analysis

    NASA Astrophysics Data System (ADS)

    Nadezhdina, I. E.; Zubarev, A. E.; Brusnikin, E. S.; Oberst, J.

    2016-06-01

    A new global control point network was derived for Enceladus, based on Cassini and Voyager-2 image data. Cassini images were taken from 2005 to 2014, for Voyager we have only one flyby in the middle of 1981. We have derived 3D Cartesian coordinates for 1128 control points as well as improved pointing data for 12 Voyager and 193 Cassini images in the Enceladus-fixed coordinate system. The point accuracies vary from 55 m to 2900 m (average point accuracy - 221 m). From tracking of the control points we detect a librational motion described by a model which includes 3 different periods and amplitudes (Rambaux et al., 2011). We determine the amplitudes for each term. Our new control point network has a higher number of point measurements and a higher accuracy than previous data (Giese et al., 2014).

  20. Pointing and control system performance and improvement strategies for the SOFIA Airborne Telescope

    NASA Astrophysics Data System (ADS)

    Graf, Friederike; Reinacher, Andreas; Jakob, Holger; Lampater, Ulrich; Pfueller, Enrico; Wiedemann, Manuel; Wolf, Jürgen; Fasoulas, Stefanos

    2016-07-01

    The Stratospheric Observatory for Infrared Astronomy (SOFIA) has already successfully conducted over 300 flights. In its early science phase, SOFIA's pointing requirements and especially the image jitter requirements of less than 1 arcsec rms have driven the design of the control system. Since the first observation flights, the image jitter has been gradually reduced by various control mechanisms. During smooth flight conditions, the current pointing and control system allows us to achieve the standards set for early science on SOFIA. However, the increasing demands on the image size require an image jitter of less than 0.4 arcsec rms during light turbulence to reach SOFIA's scientific goals. The major portion of the remaining image motion is caused by deformation and excitation of the telescope structure in a wide range of frequencies due to aircraft motion and aerodynamic and aeroacoustic effects. Therefore the so-called Flexible Body Compensation system (FBC) is used, a set of fixed-gain filters to counteract the structural bending and deformation. Thorough testing of the current system under various flight conditions has revealed a variety of opportunities for further improvements. The currently applied filters have solely been developed based on a FEM analysis. By implementing the inflight measurements in a simulation and optimization, an improved fixed-gain compensation method was identified. This paper will discuss promising results from various jitter measurements recorded with sampling frequencies of up to 400 Hz using the fast imaging tracking camera.

  1. Stability analysis of fixed points via chaos control.

    PubMed

    Locher, M.; Johnson, G. A.; Hunt, E. R.

    1997-12-01

    This paper reviews recent advances in the application of chaos control techniques to the stability analysis of two-dimensional dynamical systems. We demonstrate how the system's response to one or multiple feedback controllers can be utilized to calculate the characteristic multipliers associated with an unstable periodic orbit. The experimental results, obtained for a single and two coupled diode resonators, agree well with the presented theory. (c) 1997 American Institute of Physics.

  2. Controlled-release fertilizer (CRF): a green fertilizer for controlling non-point contamination in agriculture.

    PubMed

    Mao, Xiao-yun; Sun, Ke-jun; Wang, De-han; Liao, Zong-wen

    2005-01-01

    Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas (N2O) and eutrophication of water bodies. How to solve this problem has become a serious challenge, especially for China as its high ecological pressure. Controlled-release fertilizer(CRF) has been developed to minimize the contamination while keeping high yield and has become a green fertilizer for agriculture. Several CRFs made with special coating technology were used for testing the fertilizer effects in yield and environment through pot experiment and field trial. The result indicated that the CRFs had higher N use efficiency, thus reducing N loss through leaching and volatilization while keeping higher yields. Comparing with imported standard CRFs, the test on CRFs showed similar fertilizer effect but with much lower cost. CRFs application is becoming a new approach for minimizing non-point contamination in agriculture.

  3. 21 CFR 120.8 - Hazard Analysis and Critical Control Point (HACCP) plan.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... General Provisions § 120.8 Hazard Analysis and Critical Control Point (HACCP) plan. (a) HACCP plan. Each.... Sanitation controls may be included in the HACCP plan. However, to the extent that they are monitored in... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Hazard Analysis and Critical Control Point...

  4. [Spatial discharge characteristics and total load control of non-point source pollutants based on the catchment scale].

    PubMed

    Wang, Xia-Hui; Lu, Jun; Zhang, Qing-Zhong; Wang, Bo; Yao, Rui-Hua; Zhang, Hui-Yuan; Huang, Feng

    2011-09-01

    Agricultural non-point source pollution is one of the major causes of water quality deterioration. Based on the analysis of the spatial discharge characteristics and intensity of major pollutants from the agricultural pollution source, the establishment of spatial management subzones for controlling agricultural non-point pollution and a design of a plan for total load control of pollutants from each subzone is an important way to improve the efficiency of control measures. In this paper the Four Lake basin in Hubei Province is adopted as the research case region and a systematic research of the control countermeasures of agricultural non-point pollution based on the catchment scale is carried out. The results shows that in the Four Lake basin, the COD, total nitrogen, total phosphorus and ammonia nitrogen load of the water environment are mainly caused by agricultural non-point pollution. These four kinds of non-point source pollutants respectively account for 67.6%, 82.2%, 84.7% and 50.9% of the total pollutant discharge amount in the basin. The analysis of the spatial discharge characteristics of non-point source pollutants in the Four Lake basin shows that the major contributor source regions of non-point source pollutant in the basin are the four counties, including Honghu, Jianli, Qianjiang and Shayang where the aquatic and livestock production are relatively developed. According to the spatial discharge characteristics of the pollutants and the evaluation of the discharge intensity of pollutants, the Four Lake basin is divided into three agricultural non-point pollution management subzones, which including Changhu upstream aquatic and livestock production pollution control subzone, Four-lake trunk canal rural non-point source pollution control subzone and Honghu aquatic production pollution control subzone. Specific pollution control measures are put forward for each subzone. With a comprehensive consideration of the water quality amelioration and the

  5. [An Analysis of El Camino College Students According to Their Majors, Perceptions of Academic Relevancy, and Unit and Grade Point Characteristics.

    ERIC Educational Resources Information Center

    Garlock, Jerry

    These three separate studies of students at El Camino College (California) discuss their majors, perceptions of academic relevancy, and grade point characteristics. Sub-groups of students (freshman/sophomore, full-time/part-time) are compared according to their major divisions (physical sciences, fine arts, natural sciences, etc.) and also…

  6. 47 CFR 90.463 - Transmitter control points.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... transmitter or transmitters controlled are either radiating “RF” energy, or when the transmitter circuits have... meter may be employed to indicate the activation of both the local and the remote transmitter(s). (2) To... operator to determine when they are radiating “RF” energy or when the transmitter circuits have been...

  7. 47 CFR 90.463 - Transmitter control points.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... transmitter or transmitters controlled are either radiating “RF” energy, or when the transmitter circuits have... meter may be employed to indicate the activation of both the local and the remote transmitter(s). (2) To... operator to determine when they are radiating “RF” energy or when the transmitter circuits have been...

  8. 47 CFR 90.463 - Transmitter control points.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... transmitter or transmitters controlled are either radiating “RF” energy, or when the transmitter circuits have... meter may be employed to indicate the activation of both the local and the remote transmitter(s). (2) To... operator to determine when they are radiating “RF” energy or when the transmitter circuits have been...

  9. 47 CFR 90.463 - Transmitter control points.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... transmitter or transmitters controlled are either radiating “RF” energy, or when the transmitter circuits have... meter may be employed to indicate the activation of both the local and the remote transmitter(s). (2) To... operator to determine when they are radiating “RF” energy or when the transmitter circuits have been...

  10. 47 CFR 90.463 - Transmitter control points.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... transmitter or transmitters controlled are either radiating “RF” energy, or when the transmitter circuits have... meter may be employed to indicate the activation of both the local and the remote transmitter(s). (2) To... operator to determine when they are radiating “RF” energy or when the transmitter circuits have been...

  11. The Anopheles gambiae transcriptome - a turning point for malaria control.

    PubMed

    Domingos, A; Pinheiro-Silva, R; Couto, J; do Rosário, V; de la Fuente, J

    2017-04-01

    Mosquitoes are important vectors of several pathogens and thereby contribute to the spread of diseases, with social, economic and public health impacts. Amongst the approximately 450 species of Anopheles, about 60 are recognized as vectors of human malaria, the most important parasitic disease. In Africa, Anopheles gambiae is the main malaria vector mosquito. Current malaria control strategies are largely focused on drugs and vector control measures such as insecticides and bed-nets. Improvement of current, and the development of new, mosquito-targeted malaria control methods rely on a better understanding of mosquito vector biology. An organism's transcriptome is a reflection of its physiological state and transcriptomic analyses of different conditions that are relevant to mosquito vector competence can therefore yield important information. Transcriptomic analyses have contributed significant information on processes such as blood-feeding parasite-vector interaction, insecticide resistance, and tissue- and stage-specific gene regulation, thereby facilitating the path towards the development of new malaria control methods. Here, we discuss the main applications of transcriptomic analyses in An. gambiae that have led to a better understanding of mosquito vector competence.

  12. Pointing and control system enabling technology for future automated space missions

    NASA Technical Reports Server (NTRS)

    Dahlgren, J. B.

    1978-01-01

    Future automated space missions present challenging opportunities in the pointing-and-control technology disciplines. The enabling pointing-and-control system technologies for missions from 1985 to the year 2000 were identified and assessed. A generic mission set including Earth orbiter, planetary, and other missions which predominantly drive the pointing-and-control requirements was selected for detailed evaluation. Technology candidates identified were prioritized as planning options for future NASA-OAST advanced development programs. The primary technology thrusts in each candidate program were cited, and advanced development programs in pointing-and-control were recommended for the FY 80 to FY 87 period, based on these technology thrusts.

  13. Fixed-point vs. floating-point arithmetic comparison for adaptive optics real-time control computation

    NASA Astrophysics Data System (ADS)

    Martín-Hernando, Yolanda; Rodríguez-Ramos, Luis F.; Garcia-Talavera, Marcos R.

    2008-07-01

    Most computers in the past have been equipped with floating point processing capabilities, allowing an easy and brute-force solution for the machine computation errors, not requiring any specific tailoring of the computation in nearly hundred percent of situations. However, the computation needed for the adaptive optics real-time control in 30-50 meter telescopes is big enough to cause trouble to conventional von-Neumann processors, even if Moore's Law is valid for the next years. Field Programmable Gate Array (FPGAs) have been proposed as a viable alternative to cope with such computation needs[1,2], but--at least today's chips--will require fixed-point arithmetic to be used instead. It is then important to evaluate up to what point the accuracy and stability of the control system will be affected by this limitation. This paper presents the simulation and laboratory results of the comparison between both arithmetics, specifically evaluated in an adaptive optics system. The real-time controller has been modeled as black box having as input the wavefront sensor camera digital output data, providing a digital output to the actuators of the deformable mirror, and with the task of internally computing all outputs from the inputs. MATLAB fixed-point library has been used to evaluate the effect of different precision lengths (5-10 fractional bits) in the computation of the Shack-Hartmann subaperture centroid, in comparison with the reference 64-bit floating-point arithmetic and with the noise floor of the real system, concluding that the effect of the limited precision can be overcome by adequately selecting the number of fractional bits used in the representation, and tailoring that number with the needs at every step of the algorithm.

  14. Pointing Control System Design and Performance Evaluation for TPF Coronagraph

    NASA Technical Reports Server (NTRS)

    Liu, Kuo-Chia; Blaurock, Carl; Mosier, Gary

    2004-01-01

    The Terrestrial Planet Finder (TPF) program aims to detect and characterize extra-solar Earth-like planets. The coronagraph telescope is one of the four mission concepts being studied. In order to reject the star flux and detect the planet flux in the visible light range, the coronagraph telescope must achieve a rejection ratio on the order of a billion to one. Dynamic jitter, introduced by environmental and on-board mechanical disturbances, degrades the optical performance, as characterized primarily by contrast ratio. The feasibility of using passive vibration isolation combined with active attitude and line-of- sight control systems to stabilize the spacecraft and the optical components to the requisite level is being studied. The telescope is also required to slew between targets. The slew mode control law must be designed to balance the need for efficient large-angle maneuvers while simultaneously avoiding the excitation of flexible modes in order to minimize settling time.

  15. [The key points of Chinese children myopia prevention and control].

    PubMed

    Chu, Renyuan

    2014-01-01

    With the development of information technology and urbanization, the prevalence of myopia in Chinese children is rising each year, meanwhile, there appears to be some cognitive and behavioral misunderstanding about the prevention and treatment of myopia now. To control the development of myopia, we should make efforts to focus on prevention of myopia, promote scientific ways of diagnosis and treatment, as well as implement integrated project.

  16. Digital set point control of nonlinear stochastic systems

    NASA Technical Reports Server (NTRS)

    Moose, R. L.; Vanlandingham, H. F.; Zwicke, P. E.

    1978-01-01

    A technique for digital control of nonlinear stochastic plants is presented. The development achieves a practical digital algorithm with which the closed-loop system behaves in a classical Type I manner even with gross nonlinearities in the plant structure and low signal-to-noise power ratios. The design procedure is explained in detail and illustrated by an example whose simulated responses testify to the practicality of the approach.

  17. Earth observing system instrument pointing control modeling for polar orbiting platforms

    NASA Technical Reports Server (NTRS)

    Briggs, H. C.; Kia, T.; Mccabe, S. A.; Bell, C. E.

    1987-01-01

    An approach to instrument pointing control performance assessment for large multi-instrument platforms is described. First, instrument pointing requirements and reference platform control systems for the Eos Polar Platforms are reviewed. Performance modeling tools including NASTRAN models of two large platforms, a modal selection procedure utilizing a balanced realization method, and reduced order platform models with core and instrument pointing control loops added are then described. Time history simulations of instrument pointing and stability performance in response to commanded slewing of adjacent instruments demonstrates the limits of tolerable slew activity. Simplified models of rigid body responses are also developed for comparison. Instrument pointing control methods required in addition to the core platform control system to meet instrument pointing requirements are considered.

  18. [Monitoring of a HACCP (Hazard Analysis Critical Control Point) plan for Listeria monocytogenes control].

    PubMed

    Mengoni, G B; Apraiz, P M

    2003-01-01

    The monitoring of a HACCP (Hazard Analysis Critical Control Point) plan for the Listeria monocytogenes control in the cooked and frozen meat section of a thermo-processing meat plant was evaluated. Seventy "non-product-contact" surface samples and fourteen finished product samples were examined. Thirty eight positive sites for the presence of Listeria sp. were obtained. Twenty-two isolates were identified as L. monocytogenes, two as L. seeligeri and fourteen as L. innocua. Non isolates were obtained from finished product samples. The detection of L. monocytogenes in cooked and frozen meat section environment showed the need for the HACCP plan to eliminate or prevent product contamination in the post-thermal step.

  19. Enhancing the Mechanical Properties of Electrospun Nanofiber Mats through Controllable Welding at the Cross Points.

    PubMed

    Li, Haoxuan; Zhu, Chunlei; Xue, Jiajia; Ke, Qinfei; Xia, Younan

    2017-03-10

    This communication describes a simple and effective method for welding electrospun nanofibers at the cross points to enhance the mechanical properties of their nonwoven mats. The welding is achieved by placing a nonwoven mat of the nanofibers in a capped vial with the vapor of a proper solvent. For polycaprolactone (PCL) nanofibers, the solvent is dichloromethane (DCM). The welding can be managed in a controllable fashion by simply varying the partial pressure of DCM and/or the exposure time. Relative to the pristine nanofiber mat, the mechanical strength of the welded PCL nanofiber mat can be increased by as much as 200%. Meanwhile, such a treatment does not cause any major structural changes, including morphology, fiber diameter, and pore size. This study provides a generic method for improving the mechanical properties of nonwoven nanofiber mats, holding great potential in various applications.

  20. Syndecan-4 phosphorylation is a control point for integrin recycling.

    PubMed

    Morgan, Mark R; Hamidi, Hellyeh; Bass, Mark D; Warwood, Stacey; Ballestrem, Christoph; Humphries, Martin J

    2013-03-11

    Precise spatiotemporal coordination of integrin adhesion complex dynamics is essential for efficient cell migration. For cells adherent to fibronectin, differential engagement of α5β1 and αVβ3 integrins is used to elicit changes in adhesion complex stability, mechanosensation, matrix assembly, and migration, but the mechanisms responsible for receptor regulation have remained largely obscure. We identify phosphorylation of the membrane-intercalated proteoglycan syndecan-4 as an essential switch controlling integrin recycling. Src phosphorylates syndecan-4 and, by driving syntenin binding, leads to suppression of Arf6 activity and recycling of αVβ3 to the plasma membrane at the expense of α5β1. The resultant elevation in αVβ3 engagement promotes stabilization of focal adhesions. Conversely, abrogation of syndecan-4 phosphorylation drives surface expression of α5β1, destabilizes adhesion complexes, and disrupts cell migration. These data identify the dynamic spatiotemporal regulation of Src-mediated syndecan-4 phosphorylation as an essential switch controlling integrin trafficking and adhesion dynamics to promote efficient cell migration.

  1. 75 FR 8239 - School Food Safety Program Based on Hazard Analysis and Critical Control Point Principles (HACCP...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-24

    ... Critical Control Point Principles (HACCP); Approval of Information Collection Request AGENCY: Food and... rule entitled School Food Safety Program Based on Hazard Analysis and Critical Control Point...

  2. Point mutations in the major outer membrane protein drive hypervirulence of a rapidly expanding clone of Campylobacter jejuni

    PubMed Central

    Wu, Zuowei; Periaswamy, Balamurugan; Sahin, Orhan; Yaeger, Michael; Plummer, Paul; Zhai, Weiwei; Shen, Zhangqi; Dai, Lei; Zhang, Qijing

    2016-01-01

    Infections due to clonal expansion of highly virulent bacterial strains are clear and present threats to human and animal health. Association of genetic changes with disease is now a routine, but identification of causative mutations that enable disease remains difficult. Campylobacter jejuni is an important zoonotic pathogen transmitted to humans mainly via the foodborne route. C. jejuni typically colonizes the gut, but a hypervirulent and rapidly expanding clone of C. jejuni recently emerged, which is able to translocate across the intestinal tract, causing systemic infection and abortion in pregnant animals. The genetic basis responsible for this hypervirulence is unknown. Here, we developed a strategy, termed “directed genome evolution,” by using hybridization between abortifacient and nonabortifacient strains followed by selection in an animal disease model and whole-genome sequence analysis. This strategy successfully identified SNPs in porA, encoding the major outer membrane protein, are responsible for the hypervirulence. Defined mutagenesis verified that these mutations were both necessary and sufficient for causing abortion. Furthermore, sequence analysis identified porA as the gene with the top genome-wide signal of adaptive evolution using Fu’s Fs, a population genetic metric for recent population size changes, which is consistent with the recent expansion of clone “sheep abortion.” These results identify a key virulence factor in Campylobacter and a potential target for the control of this zoonotic pathogen. Furthermore, this study provides general, unbiased experimental and computational approaches that are broadly applicable for efficient elucidation of disease-causing mutations in bacterial pathogens. PMID:27601641

  3. Hubble Space Telescope pointing control system: Designed for performance and mission operations

    NASA Technical Reports Server (NTRS)

    Bradley, A.; Ryan, J.

    1991-01-01

    The Hubble Space Telescope was designed to be an orbiting astronomical observatory which could be operated in the same manner as ground based observatories. The design drivers for the pointing control system's hardware and software were the requirements of an absolute pointing accuracy of 4.8E-8 radians and pointing stability (jitter) of 3.4E-8 radians. Of comparable importance was the objective of providing a flexible command methodology and structure to enable seven day operational planning employing stored program command and real time command capability. The pointing control system hardware, software, safemode control schemes, ground system monitoring capability, and in-orbit results are reviewed.

  4. Parameter Space of Fixed Points of the Damped Driven Pendulum Susceptible to Control of Chaos Algorithms

    NASA Astrophysics Data System (ADS)

    Dittmore, Andrew; Trail, Collin; Olsen, Thomas; Wiener, Richard J.

    2003-11-01

    We have previously demonstrated the experimental control of chaos in a Modified Taylor-Couette system with hourglass geometry( Richard J. Wiener et al), Phys. Rev. Lett. 83, 2340 (1999).. Identifying fixed points susceptible to algorithms for the control of chaos is key. We seek to learn about this process in the accessible numerical model of the damped, driven pendulum. Following Baker(Gregory L. Baker, Am. J. Phys. 63), 832 (1995)., we seek points susceptible to the OGY(E. Ott, C. Grebogi, and J. A. Yorke, Phys. Rev. Lett. 64), 1196 (1990). algorithm. We automate the search for fixed points that are candidates for control. We present comparisons of the space of candidate fixed points with the bifurcation diagrams and Poincare sections of the system. We demonstrate control at fixed points which do not appear on the attractor. We also show that the control algorithm may be employed to shift the system between non-communicating branches of the attractor.

  5. Robust optimal sun-pointing control of a large solar power satellite

    NASA Astrophysics Data System (ADS)

    Wu, Shunan; Zhang, Kaiming; Peng, Haijun; Wu, Zhigang; Radice, Gianmarco

    2016-10-01

    The robust optimal sun-pointing control strategy for a large geostationary solar power satellite (SPS) is addressed in this paper. The SPS is considered as a huge rigid body, and the sun-pointing dynamics are firstly proposed in the state space representation. The perturbation effects caused by gravity gradient, solar radiation pressure and microwave reaction are investigated. To perform sun-pointing maneuvers, a periodically time-varying robust optimal LQR controller is designed to assess the pointing accuracy and the control inputs. It should be noted that, to reduce the pointing errors, the disturbance rejection technique is combined into the proposed LQR controller. A recursive algorithm is then proposed to solve the optimal LQR control gain. Simulation results are finally provided to illustrate the performance of the proposed closed-loop system.

  6. [Microbiological controls and control points in a hake fillets manufacturing process for exportation].

    PubMed

    Estevao Belchior, S; Pucci, O H

    2000-06-01

    Indicator and foodborne pathogen microorganisms in the "for export" hake fillets manufacturing were investigated in this study. Critical control points were identified and prevention activities and control were proposed during seafood elaboration process. 45 samples of hake from sequential processing operation stages, 15 ice samples and 12 water samples from utensil washing, were collected. The samples were analyzed for their content of aerobic mesophilic bacteria, psychrotrophic bacteria, enterobacteria, total and fecal coliform bacteria, Staphylococcus aureus and the presence of Escherichia coli, Salmonella and Shigella. The analysis of the samples collected from the factory revealed that the amounts of aerobic mesophile bacteria increased during manual filleting and packaging, in comparison with raw material. Psychrotrophic bacteria were the predominant microorganisms, specially in hake samples. In addition, high levels of enterobacteria, which do not occur normally in fish, were detected in raw hake samples. Staphylococcus aureus, Escherichia coli, Salmonella and Shigella, were not isolated from any samples in this study. The goal of this work is to establish microbiological risks in the hake fillets manufacturing process and, therefore to make possible corrective and control actions to assure the quality and safety of seafood.

  7. The point of no return: A fundamental limit on the ability to control thought and action.

    PubMed

    Logan, Gordon D

    2015-01-01

    Bartlett (1958. Thinking. New York: Basic Books) described the point of no return as a point of irrevocable commitment to action, which was preceded by a period of gradually increasing commitment. As such, the point of no return reflects a fundamental limit on the ability to control thought and action. I review the literature on the point of no return, taking three perspectives. First, I consider the point of no return from the perspective of the controlled act, as a locus in the architecture and anatomy of the underlying processes. I review experiments from the stop-signal paradigm that suggest that the point of no return is located late in the response system. Then I consider the point of no return from the perspective of the act of control that tries to change the controlled act before it becomes irrevocable. From this perspective, the point of no return is a point in time that provides enough "lead time" for the act of control to take effect. I review experiments that measure the response time to the stop signal as the lead time required for response inhibition in the stop-signal paradigm. Finally, I consider the point of no return in hierarchically controlled tasks, in which there may be many points of no return at different levels of the hierarchy. I review experiments on skilled typing that suggest different points of no return for the commands that determine what is typed and the countermands that inhibit typing, with increasing commitment to action the lower the level in the hierarchy. I end by considering the point of no return in perception and thought as well as action.

  8. Barriers to Point-of-Care Testing in India: Results from Qualitative Research across Different Settings, Users and Major Diseases

    PubMed Central

    Engel, Nora; Ganesh, Gayatri; Patil, Mamata; Yellappa, Vijayashree; Pant Pai, Nitika; Vadnais, Caroline; Pai, Madhukar

    2015-01-01

    Background Successful point-of-care testing, namely ensuring the completion of the test and treat cycle in the same encounter, has immense potential to reduce diagnostic and treatment delays, and impact patient outcomes. However, having rapid tests is not enough, as many barriers may prevent their successful implementation in point-of-care testing programs. Qualitative research on diagnostic practices may help identify such barriers across different points of care in health systems. Methods In this exploratory qualitative study, we conducted 78 semi-structured interviews and 13 focus group discussions in an urban and rural area of Karnataka, India, with healthcare providers (doctors, nurses, specialists, traditional healers, and informal providers), patients, community health workers, test manufacturers, laboratory technicians, program managers and policy-makers. Participants were purposively sampled to represent settings of hospitals, peripheral labs, clinics, communities and homes, in both the public and private sectors. Results In the Indian context, the onus is on the patient to ensure successful point-of-care testing across homes, clinics, labs and hospitals, amidst uncoordinated providers with divergent and often competing practices, in settings lacking material, money and human resources. We identified three overarching themes affecting point-of-care testing: the main theme is ‘relationships’ among providers and between providers and patients, influenced by the cross-cutting theme of ‘infrastructure’. Challenges with both result in ‘modified practices’ often favouring empirical (symptomatic) treatment over treatment guided by testing. Conclusions Even if tests can be conducted on the spot and infrastructure challenges have been resolved, relationships among providers and between patients and providers are crucial for successful point-of-care testing. Furthermore, these barriers do not act in isolation, but are interlinked and need to be examined

  9. 47 CFR 90.471 - Points of operation in internal transmitter control systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... control systems. 90.471 Section 90.471 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control Internal Transmitter Control Systems § 90.471 Points of operation in internal transmitter control systems....

  10. 47 CFR 90.471 - Points of operation in internal transmitter control systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... control systems. 90.471 Section 90.471 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control Internal Transmitter Control Systems § 90.471 Points of operation in internal transmitter control systems....

  11. Design of a new high-performance pointing controller for the Hubble Space Telescope

    NASA Technical Reports Server (NTRS)

    Johnson, C. D.

    1993-01-01

    A new form of high-performance, disturbance-adaptive pointing controller for the Hubble Space Telescope (HST) is proposed. This new controller is all linear (constant gains) and can maintain accurate 'pointing' of the HST in the face of persistent randomly triggered uncertain, unmeasurable 'flapping' motions of the large attached solar array panels. Similar disturbances associated with antennas and other flexible appendages can also be accommodated. The effectiveness and practicality of the proposed new controller is demonstrated by a detailed design and simulation testing of one such controller for a planar-motion, fully nonlinear model of HST. The simulation results show a high degree of disturbance isolation and pointing stability.

  12. Optimization of block-floating-point realizations for digital controllers with finite-word-length considerations.

    PubMed

    Wu, Jun; Hu, Xie-he; Chen, Sheng; Chu, Jian

    2003-01-01

    The closed-loop stability issue of finite-precision realizations was investigated for digital controllers implemented in block-floating-point format. The controller coefficient perturbation was analyzed resulting from using finite word length (FWL) block-floating-point representation scheme. A block-floating-point FWL closed-loop stability measure was derived which considers both the dynamic range and precision. To facilitate the design of optimal finite-precision controller realizations, a computationally tractable block-floating-point FWL closed-loop stability measure was then introduced and the method of computing the value of this measure for a given controller realization was developed. The optimal controller realization is defined as the solution that maximizes the corresponding measure, and a numerical optimization approach was adopted to solve the resulting optimal realization problem. A numerical example was used to illustrate the design procedure and to compare the optimal controller realization with the initial realization.

  13. Cadmium and lead residue control in a hazard analysis and critical control point (HACCP) environment.

    PubMed

    Pagan-Rodríguez, Doritza; O'Keefe, Margaret; Deyrup, Cindy; Zervos, Penny; Walker, Harry; Thaler, Alice

    2007-02-21

    In 2003-2004, the U.S. Department of Agriculture Food Safety and Inspection Service (FSIS) conducted an exploratory assessment to determine the occurrence and levels of cadmium and lead in randomly collected samples of kidney, liver, and muscle tissues of mature chickens, boars/stags, dairy cows, and heifers. The data generated in the study were qualitatively compared to data that FSIS gathered in a 1985-1986 study in order to identify trends in the levels of cadmium and lead in meat and poultry products. The exploratory assessment was necessary to verify that Hazard Analysis and Critical Control Point plans and efforts to control exposure to these heavy metals are effective and result in products that meet U.S. export requirements. A comparison of data from the two FSIS studies suggests that the incidence and levels of cadmium and lead in different slaughter classes have remained stable since the first study was conducted in 1985-1986. This study was conducted to fulfill FSIS mandate to ensure that meat, poultry, and egg products entering commerce in the United States are free of adulterants, including elevated levels of environmental contaminants such as cadmium and lead.

  14. Methodological demonstration of laser beam pointing control for space gravitational wave detection missions.

    PubMed

    Dong, Yu-Hui; Liu, He-Shan; Luo, Zi-Ren; Li, Yu-Qiong; Jin, Gang

    2014-07-01

    In space laser interferometer gravitational wave (G.W.) detection missions, the stability of the laser beam pointing direction has to be kept at 10 nrad/√Hz. Otherwise, the beam pointing jitter noise will dominate the noise budget and make the detection of G.W. impossible. Disturbed by the residue non-conservative forces, the fluctuation of the laser beam pointing direction could be a few μrad/√Hz at frequencies from 0.1 mHz to 10 Hz. Therefore, the laser beam pointing control system is an essential requirement for those space G.W. detection missions. An on-ground test of such beam pointing control system is performed, where the Differential Wave-front Sensing technique is used to sense the beams pointing jitter. An active controlled steering mirror is employed to adjust the beam pointing direction to compensate the jitter. The experimental result shows that the pointing control system can be used for very large dynamic range up to 5 μrad. At the interested frequencies of space G.W. detection missions, between 1 mHz and 1 Hz, beam pointing stability of 6 nrad/√Hz is achieved.

  15. Solar array pointing control for the International Space Station electrical power subsystem to optimize power delivery

    SciTech Connect

    Hill, R.C.

    1998-07-01

    Precise orientation control of the International Space Station (ISS) Electrical Power System (EPS) photovoltaic (PV) solar arrays is required for a number of reasons, including the optimization of power delivery to ISS system loads and payloads. To maximize power generation and delivery in general, the PV arrays are pointed directly at the sun with some allowance for inaccuracies in determination of where to point and in the actuation of pointing the PV arrays. Control of PV array orientation in this sun pointing mode is performed automatically by onboard hardware and software. During certain conditions, maximum power cannot be generated in automatic sun tracking mode due to shadowing of the PV arrays cast by other ISS structures, primarily adjacent PV arrays. In order to maximize the power generated, the PV arrays must be pointed away from the ideal sun pointing targets to reduce the amount of shadowing. The amount of off-pointing to maximize power is a function of many parameters such as the physical configuration of the ISS structures during the assembly timeframe, the solar beta angle and vehicle attitude. Thus the off-pointing cannot be controlled automatically and must be determined by ground operators. This paper presents an overview of ISS PV array orientation control, PV array power performance under shadowed and off-pointing conditions, and a methodology to maximize power under those same conditions.

  16. Autonomous Pointing Control of a Large Satellite Antenna Subject to Parametric Uncertainty

    PubMed Central

    Wu, Shunan; Liu, Yufei; Radice, Gianmarco; Tan, Shujun

    2017-01-01

    With the development of satellite mobile communications, large antennas are now widely used. The precise pointing of the antenna’s optical axis is essential for many space missions. This paper addresses the challenging problem of high-precision autonomous pointing control of a large satellite antenna. The pointing dynamics are firstly proposed. The proportional–derivative feedback and structural filter to perform pointing maneuvers and suppress antenna vibrations are then presented. An adaptive controller to estimate actual system frequencies in the presence of modal parameters uncertainty is proposed. In order to reduce periodic errors, the modified controllers, which include the proposed adaptive controller and an active disturbance rejection filter, are then developed. The system stability and robustness are analyzed and discussed in the frequency domain. Numerical results are finally provided, and the results have demonstrated that the proposed controllers have good autonomy and robustness. PMID:28287450

  17. Autonomous Pointing Control of a Large Satellite Antenna Subject to Parametric Uncertainty.

    PubMed

    Wu, Shunan; Liu, Yufei; Radice, Gianmarco; Tan, Shujun

    2017-03-10

    With the development of satellite mobile communications, large antennas are now widely used. The precise pointing of the antenna's optical axis is essential for many space missions. This paper addresses the challenging problem of high-precision autonomous pointing control of a large satellite antenna. The pointing dynamics are firstly proposed. The proportional-derivative feedback and structural filter to perform pointing maneuvers and suppress antenna vibrations are then presented. An adaptive controller to estimate actual system frequencies in the presence of modal parameters uncertainty is proposed. In order to reduce periodic errors, the modified controllers, which include the proposed adaptive controller and an active disturbance rejection filter, are then developed. The system stability and robustness are analyzed and discussed in the frequency domain. Numerical results are finally provided, and the results have demonstrated that the proposed controllers have good autonomy and robustness.

  18. [A landscape ecological approach for urban non-point source pollution control].

    PubMed

    Guo, Qinghai; Ma, Keming; Zhao, Jingzhu; Yang, Liu; Yin, Chengqing

    2005-05-01

    Urban non-point source pollution is a new problem appeared with the speeding development of urbanization. The particularity of urban land use and the increase of impervious surface area make urban non-point source pollution differ from agricultural non-point source pollution, and more difficult to control. Best Management Practices (BMPs) are the effective practices commonly applied in controlling urban non-point source pollution, mainly adopting local repairing practices to control the pollutants in surface runoff. Because of the close relationship between urban land use patterns and non-point source pollution, it would be rational to combine the landscape ecological planning with local BMPs to control the urban non-point source pollution, which needs, firstly, analyzing and evaluating the influence of landscape structure on water-bodies, pollution sources and pollutant removal processes to define the relationships between landscape spatial pattern and non-point source pollution and to decide the key polluted fields, and secondly, adjusting inherent landscape structures or/and joining new landscape factors to form new landscape pattern, and combining landscape planning and management through applying BMPs into planning to improve urban landscape heterogeneity and to control urban non-point source pollution.

  19. Wireless power charging using point of load controlled high frequency power converters

    DOEpatents

    Miller, John M.; Campbell, Steven L.; Chambon, Paul H.; Seiber, Larry E.; White, Clifford P.

    2015-10-13

    An apparatus for wirelessly charging a battery of an electric vehicle is provided with a point of load control. The apparatus includes a base unit for generating a direct current (DC) voltage. The base unit is regulated by a power level controller. One or more point of load converters can be connected to the base unit by a conductor, with each point of load converter comprising a control signal generator that transmits a signal to the power level controller. The output power level of the DC voltage provided by the base unit is controlled by power level controller such that the power level is sufficient to power all active load converters when commanded to do so by any of the active controllers, without generating excessive power that may be otherwise wasted.

  20. Point-of-care testing for HIV in an Irish prison setting: results from three major Irish prisons.

    PubMed

    Bannan, Ciaran L; Lynch, Pamela A; Conroy, Emmett P; O'Dea, Siobhan; Surah, Saloni; Betts-Symonds, Graham; Lyons, Fiona E

    2016-10-01

    HIV is more prevalent in the prison population compared to the general population. Prison inmates are at an increased risk of blood-borne infections. Considerable stigma has been documented amongst inmates with HIV infection. In collaboration with the schools, healthcare facilities, prison authorities and inmate Irish Red Cross groups in Wheatfield, Cloverhill and Mountjoy prisons in Dublin, Ireland, the Department of Genito Urinary Medicine and Infectious Diseases at St James' Hospital in Dublin developed a campaign for raising awareness of HIV, educating inmates about HIV and tackling HIV stigma. Following this campaign, large-scale point-of-care testing for HIV was offered over a short period. In total, 741 inmates were screened for HIV. One inmate tested positive for HIV. We experienced a large number of invalid test results, requiring formal laboratory serum testing, and a small number of false positive results. Large-scale point-of-care testing in the Irish prison setting is acceptable and achievable.

  1. [Development and applications of the extracorporeal control point module on multi-mode medical images].

    PubMed

    Chen, Zhao-Qiu; Zhao, Feng-Ling; Zhu, Jian; Li, Wan-Hu; Fu, Zheng; Hu, Xu-Dong

    2008-07-01

    This paper introduces a display module which can be used on multi-mode medical images. The module has a small size and can be easily used for point-selecting puncture diagnosis and treatment, and registration for image fusion control points.

  2. A Non-Linear Approach to Spacecraft Trajectory Control in the Vicinity of a Libration Point

    NASA Technical Reports Server (NTRS)

    Luquette, Richard J.; Sanner, Robert M.

    2001-01-01

    An expanding interest in mission design strategies that exploit libration point regions demands the continued development of enhanced, efficient, control algorithms for station-keeping and formation maintenance. This paper discusses the development of a non-linear, station-keeping, control algorithm for trajectories in the vicinity of a libration point. The control law guarantees exponential convergence, based on a Lyaponov analysis. Controller performance is evaluated using FreeFlyer(R) and MATLAB(R) for a spacecraft stationed near the L2 libration point in the Earth-Moon system, tracking a pre-defined reference trajectory. Evaluation metrics are fuel usage and tracking accuracy. Simulation results are compared with a linear-based controller for a spacecraft tracking the same reference trajectory. Although the analysis is framed in the context of station-keeping, the control algorithm is equally applicable to a formation flying problem with an appropriate definition of the reference trajectory.

  3. Modeling, Identification, and Control Design for a Flexible Pointing System with Embedded Smart Materials.

    DTIC Science & Technology

    2007-11-02

    The research effort emphasized system identification , decentralized control design, and their applications to smart structures and flexible pointing...systems. The research effort had both theoretical and experimental ingredients. On the theoretical side, new system identification techniques for

  4. Dynamic and control assessment of the Space Station Freedom payload pointing system

    NASA Technical Reports Server (NTRS)

    Shannon, David T., Jr.

    1991-01-01

    An analysis of the proposed Space Station Freedom Payload Pointing System (PPS) was performed to assess its dynamic payload pointing capability in the dynamic environment of the Space Station Freedom (SSF). In addition, the stability and control the the SSF was examined to verify the capability of its control devices to accommodate the impact of PPS operations. An analysis of the PPS ability to provide continuous, accurate pointing was performed and compared to the program requirements specified in the 1988 Program Definition and Requirement Document (PDRD). Results indicated that the PPS was not able to perform within the program requirements during the worst case scenario of a shuttle hard docking maneuver to the port side SSF docking adapter. The PPS maintained marginal pointing accuracy during crew treadmill activity. The Space Station attitude control system easily accommodated all PPS operations simulated. The PPS caused a negligible impact on the SSF's control environment.

  5. Hazard analysis and critical control point systems applied to public health risks: the example of seafood.

    PubMed

    Williams, R A; Zorn, D J

    1997-08-01

    The authors describe the way in which the two components of risk analysis--risk assessment and risk management--can be used in conjunction with the hazard analysis and critical control points concept to determine the allocation of resources at potential critical control points. This approach is examined in the context of risks to human health associated with seafood, and in particular with regard to ciguatera poisoning.

  6. The Feasibility of the Disturbance Accommodating Controller for Precision Antenna Pointing

    NASA Technical Reports Server (NTRS)

    Gresham, L. L.; Lansing, F. L.; Guiar, C. N.

    1988-01-01

    The objective of this study is to investigate the feasibility of a pointing (position loop) controller for the NASA-JPL Deep Space Network (DSN) antennas using the Disturbance Accommodating Control (DAC) theory. A model that includes state dependent disturbances was developed, and an example demonstrating the noise estimator is presented as an initial phase in the controller design. The goal is to improve pointing accuracy by the removal of the systematic errors caused by the antenna misalignment as well as sensor noise and random wind and thermal disturbances. Preliminary simulation results show that the DAC technique is successful in both cancelling the imposed errors and maintaining an optimal control policy.

  7. Fish oil supplementation in the treatment of major depression: a randomised double-blind placebo-controlled trial.

    PubMed

    Grenyer, Brin F S; Crowe, Trevor; Meyer, Barbara; Owen, Alice J; Grigonis-Deane, Elizabeth M; Caputi, Peter; Howe, Peter R C

    2007-10-01

    Dietary deficiencies in essential omega-3 polyunsaturated fatty acids derived from fish are associated with depression and some fish oils may have therapeutic benefits. We aimed to determine whether taking tuna fish oil confers any additional benefit to conventional outpatient treatment for major depression. A randomized double-blind placebo-controlled four-month trial comparing tuna fish oil versus placebo was conducted on 83 outpatients with major depression. Despite large reductions in depression there were no significant differences at any assessment time point between patients receiving fish oil compared to placebo. Red blood cell incorporation of fatty acids indicated good compliance with oil supplementation, although this sample was not initially deficient in omega-3s. This particular dose and type of fish oil conferred no additional benefit to conventional treatment of depression in this sample. Future studies could target participants with pre-existing omega-3 deficiency and appraise alternate enriched types and higher doses of omega-3 supplementation.

  8. Disease progression subtype discovery from longitudinal EMR data with a majority of missing values and unknown initial time points

    PubMed Central

    Huopaniemi, Ilkka; Nadkarni, Girish; Nadukuru, Rajiv; Lotay, Vaneet; Ellis, Steve; Gottesman, Omri; Bottinger, Erwin P

    2014-01-01

    Electronic medical records (EMR) contain a longitudinal collection of laboratory data that contains valuable phenotypic information on disease progression of a large collection of patients. These data can be potentially used in medical research or patient care; finding disease progression subtypes is a particularly important application. There are, however, two significant difficulties in utilizing this data for statistical analysis: (a) a large proportion of data is missing and (b) patients are in very different stages of disease progression and there are no well-defined start points of the time series. We present a Bayesian machine learning model that overcomes these difficulties. The method can use highly incomplete time-series measurement of varying lengths, it aligns together similar trajectories in different phases and is capable of finding consistent disease progression subtypes. We demonstrate the method on finding chronic kidney disease progression subtypes. PMID:25954377

  9. Simulation of flexible appendage interactions with Mariner Venus/Mercury attitude control and science platform pointing

    NASA Technical Reports Server (NTRS)

    Fleischer, G. E.

    1973-01-01

    A new computer subroutine, which solves the attitude equations of motion for any vehicle idealized as a topological tree of hinge-connected rigid bodies, is used to simulate and analyze science instrument pointing control interaction with a flexible Mariner Venus/Mercury (MVM) spacecraft. The subroutine's user options include linearized or partially linearized hinge-connected models whose computational advantages are demonstrated for the MVM problem. Results of the pointing control/flexible vehicle interaction simulations, including imaging experiment pointing accuracy predictions and implications for MVM science sequence planning, are described in detail.

  10. Antenna pointing system for satellite tracking based on Kalman filtering and model predictive control techniques

    NASA Astrophysics Data System (ADS)

    Souza, André L. G.; Ishihara, João Y.; Ferreira, Henrique C.; Borges, Renato A.; Borges, Geovany A.

    2016-12-01

    The present work proposes a new approach for an antenna pointing system for satellite tracking. Such a system uses the received signal to estimate the beam pointing deviation and then adjusts the antenna pointing. The present work has two contributions. First, the estimation is performed by a Kalman filter based conical scan technique. This technique uses the Kalman filter avoiding the batch estimator and applies a mathematical manipulation avoiding the linearization approximations. Secondly, a control technique based on the model predictive control together with an explicit state feedback solution are obtained in order to reduce the computational burden. Numerical examples illustrate the results.

  11. Costs and water quality effects of controlling point and nonpoint pollution sources

    SciTech Connect

    Macal, C.M.; Broomfield, B.J.

    1980-01-01

    Costs and water quality effects of controlling point and nonpoint pollution sources are compared for the DuPage River basin in northern Illinois. Costs are estimated for effluent standards for municipal wastewater treatment plants and for the alternative, controlling runoff from nonpoint sources such as streets, agricultural lands, and forests. A dynamic water-quality/hydrology simulation model is used to determine water quality effects of various treatment plant standards and nonpoint-source controls. Costs and water quality data are combined, and the point-source and nonpoint-source plans are compared on a cost-effectiveness basis. Nonpoint-source controls are found to be more cost-effective than stricter control of pollutants from point sources.

  12. Precision beam pointing control with jitter attenuation by optical deflector exhibiting dynamic hysteresis in COIL

    NASA Astrophysics Data System (ADS)

    Ma, Yan-Hua; Zhang, Zeng-Bao; Zhang, Zhi-Guo; Liu, Qin; He, Xin; Shi, Wen-Bo; Mao, Jian-Qin; Jin, Yu-Qi

    2015-02-01

    Due to the existence of various disturbances during the lasing process of the chemical oxygen iodine laser (COIL), the optical beam pointing performance is severely degraded. In this paper, an adaptive control methodology is proposed for the precise pointing control of the optical beam with active beam jitter rejection using a giant magnetostrictive optical deflector (GMOD) which exhibits severe dynamic hysteresis nonlinearity. In particular, a least square support vector machine (LS-SVM) based fast compensator is employed to eliminate the dynamic hysteresis without the inverse model construction. Then an improved feedforward adaptive filter is developed to deal with jitter attenuation when the full-coherent reference signal is unavailable. To improve the stability and overall robustness of the controller, especially when a large initial bias exists, a PI controller is placed in parallel with the adaptive filter. Experimental results validate the precise pointing ability of the proposed control method.

  13. Global shape estimates and GIS cartography of Io and Enceladus using new control point network

    NASA Astrophysics Data System (ADS)

    Nadezhdina, I.; Patraty, V.; Shishkina, L.; Zhukov, D.; Zubarev, A.; Karachevtseva, I.; Oberst, J.

    2012-04-01

    We have analyzed a total of 53 Galileo and Voyager images of Io and 54 Cassini images of Enceladus to derive new geodetic control point networks for the two satellites. In order to derive the network for Io we used a subset of 66 images from those used in previous control point network studies [1, 2]. Additionally we have carried out new point measurements. We used recently reconstructed Galileo spacecraft trajectory data, supplied by the spacecraft navigation team of JPL. A total of 1956 tie point measurements for Io and 4392 ones for Enceladus have been carried out, which were processed by performing photogrammetric bundle block adjustments. Measurements and block adjustments were performed by means of the «PHOTOMOD» software [3] which was especially adapted for this study to accommodate global networks of small bodies, such as Io and Enceladus. As a result, two catalogs with the Cartesian three-dimensional coordinates of 197 and 351 control points were obtained for Io and Enceladus, respectively. The control points for Io have a mean overall accuracy of 4985.7 m (RMS). The individual accuracy of the control points for Enceladus differ substantially over the surface (the range is from 0.1 to 36.0 km) because images lack coverage and resolutions. We also determine best-fit spheres, spheroids, and tri-axial ellipsoids. The centers of the models were found to be shifted from the coordinate system origin attesting to possible errors in the ephemeris of Io. Conclusion and Future work: A comparison of our results for Io with the most recent control point network analysis [2] has revealed that we managed to derive the same accuracy of the control points using a smaller number of images and measurements (This study: 1956 measurements, DLR study: 4392). This probably attests to the fact that the now available new navigation data are internally more consistent. At present an analysis of the data is in progress. We report that control point measurements and global network

  14. Control of end-point forces of a multijoint limb by functional neuromuscular stimulation.

    PubMed

    Lan, N; Crago, P E; Chizeck, H J

    1991-10-01

    A multivariable feedback controller was designed and tested for regulating the magnitude and orientation of the force vector at the end point of a multijoint limb in contact with an isometric load. The force vector was produced by electrical stimulation of muscles. To achieve arbitrary control of end-point force magnitude and orientation, two coupling issues must be dealt with by the control system. First, there is a geometric coupling between the end-point force vector and joint torques. The amplitude and orientation of the force vector depend on the limb geometry. Second, torques at two joints may be coupled due to activation of muscles that cross them (biarticular coupling). To eliminate the geometric coupling, a transformation of controller error from the Cartesian space to the joint space was employed. A multivariable proportional-plus-integral (PI) control law was used to calculate muscle activation based on the transformed controller error. Centralized and decentralized controls were investigated for decoupling the effects of biarticular muscles. The results obtained from cat experiments showed that the magnitude and orientation of the end-point forces of the cat hindlimb could be regulated by this controller. In the presence of strong biarticular coupling, centralized control yielded better performance than decentralized control during transient responses. Both control strategies could decouple the biarticular muscle at steady state. When no biarticular coupling was present, centralized control sometimes performed worse than decentralized control. This is the first step in the simultaneous control of multiple joints by functional neuromuscular stimulation (FNS). The controller has broad potential applications in FNS neural prostheses.

  15. Paleogeographic controls of coal accumulation, Cretaceous Blackhawk Formation and Star Point Sandstone, Wasatch Plateau, Utah.

    USGS Publications Warehouse

    Flores, R.M.; Blanchard, L.F.; Sanchez, J.D.; Marley, W.E.; Muldoon, W.J.

    1984-01-01

    Considers the paleogeographic controls affecting the accumulation of coals in delta-barrier-island complexes. Progradation, lateral shifting, and abandonment of these complexes created four major landward-thinning tongues.-from Authors

  16. Reduced Anterior Cingulate Glutamatergic Concentrations in Childhood Ocd and Major Depression Versus Healthy Controls

    ERIC Educational Resources Information Center

    Rosenberg, David R.; Mirza, Yousha; Russell, Aileen; Tang, Jennifer; Smith, Janet M.; Banerjee, Preeya S.; Bhandari, Rashmi; Rose, Michelle; Ivey, Jennifer; Boyd, Courtney; Moore, Gregory J.

    2004-01-01

    Objective: To examine in vivo glutamatergic neurochemical alterations in the anterior cingulate cortex of pediatric patients with obsessive-compulsive disorder (OCD) without major depressive disorder (MDD) versus pediatric patients with MDD without OCD and healthy controls. Method: Single-voxel proton magnetic resonance spectroscopic examinations…

  17. Fluoxetine, Smoking, and History of Major Depression: A Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Spring, Bonnie; Doran, Neal; Pagoto, Sherry; McChargue, Dennis; Cook, Jessica Werth; Bailey, Katherine; Crayton, John; Hedeker, Donald

    2007-01-01

    The study was a randomized placebo-controlled trial testing whether fluoxetine selectively enhances cessation for smokers with a history of depression. Euthymic smokers with (H+, n = 109) or without (H-, n = 138) a history of major depression received 60 mg fluoxetine or placebo plus group behavioral quit-smoking treatment for 12 weeks. Fluoxetine…

  18. 47 CFR 90.471 - Points of operation in internal transmitter control systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... licensee for internal communications and transmitter control purposes. Operating positions in internal... 47 Telecommunication 5 2012-10-01 2012-10-01 false Points of operation in internal transmitter control systems. 90.471 Section 90.471 Telecommunication FEDERAL COMMUNICATIONS COMMISSION...

  19. 47 CFR 90.471 - Points of operation in internal transmitter control systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... licensee for internal communications and transmitter control purposes. Operating positions in internal... 47 Telecommunication 5 2014-10-01 2014-10-01 false Points of operation in internal transmitter control systems. 90.471 Section 90.471 Telecommunication FEDERAL COMMUNICATIONS COMMISSION...

  20. 47 CFR 90.471 - Points of operation in internal transmitter control systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... licensee for internal communications and transmitter control purposes. Operating positions in internal... 47 Telecommunication 5 2013-10-01 2013-10-01 false Points of operation in internal transmitter control systems. 90.471 Section 90.471 Telecommunication FEDERAL COMMUNICATIONS COMMISSION...

  1. Hazard analysis and critical control point (HACCP) history and conceptual overview.

    PubMed

    Hulebak, Karen L; Schlosser, Wayne

    2002-06-01

    The concept of Hazard Analysis and Critical Control Point (HACCP) is a system that enables the production of safe meat and poultry products through the thorough analysis of production processes, identification of all hazards that are likely to occur in the production establishment, the identification of critical points in the process at which these hazards may be introduced into product and therefore should be controlled, the establishment of critical limits for control at those points, the verification of these prescribed steps, and the methods by which the processing establishment and the regulatory authority can monitor how well process control through the HACCP plan is working. The history of the development of HACCP is reviewed, and examples of practical applications of HACCP are described.

  2. Major parasitic diseases of poverty in mainland China: perspectives for better control.

    PubMed

    Wang, Jin-Lei; Li, Ting-Ting; Huang, Si-Yang; Cong, Wei; Zhu, Xing-Quan

    2016-08-01

    Significant progress has been made in the prevention, control, and elimination of human parasitic diseases in China in the past 60 years. However, parasitic diseases of poverty remain major causes of morbidity and mortality, and inflict enormous economic costs on societies.In this article, we review the prevalence rates, geographical distributions, epidemic characteristics, risk factors, and clinical manifestations of parasitic diseases of poverty listed in the first issue of the journal Infectious Diseases of Poverty on 25 October 2012. We also address the challenges facing control of parasitic diseases of poverty and provide suggestions for better control.

  3. Acupuncture-Point Stimulation for Postoperative Pain Control: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

    PubMed Central

    Liu, Xian-Liang; Tan, Jing-Yu; Molassiotis, Alex; Suen, Lorna K. P.; Shi, Yan

    2015-01-01

    The purpose of this study was to evaluate the effectiveness of Acupuncture-point stimulation (APS) in postoperative pain control compared with sham/placebo acupuncture or standard treatments (usual care or no treatment). Only randomized controlled trials (RCTs) were included. Meta-analysis results indicated that APS interventions improved VAS scores significantly and also reduced total morphine consumption. No serious APS-related adverse effects (AEs) were reported. There is Level I evidence for the effectiveness of body points plaster therapy and Level II evidence for body points electroacupuncture (EA), body points acupressure, body points APS for abdominal surgery patients, auricular points seed embedding, manual auricular acupuncture, and auricular EA. We obtained Level III evidence for body points APS in patients who underwent cardiac surgery and cesarean section and for auricular-point stimulation in patients who underwent abdominal surgery. There is insufficient evidence to conclude that APS is an effective postoperative pain therapy in surgical patients, although the evidence does support the conclusion that APS can reduce analgesic requirements without AEs. The best level of evidence was not adequate in most subgroups. Some limitations of this study may have affected the results, possibly leading to an overestimation of APS effects. PMID:26568767

  4. Attitude control/momentum management and payload pointing in advanced space vehicles

    NASA Technical Reports Server (NTRS)

    Parlos, Alexander G.; Jayasuriya, Suhada

    1990-01-01

    The design and evaluation of an attitude control/momentum management system for highly asymmetric spacecraft configurations are presented. The preliminary development and application of a nonlinear control system design methodology for tracking control of uncertain systems, such as spacecraft payload pointing systems are also presented. Control issues relevant to both linear and nonlinear rigid-body spacecraft dynamics are addressed, whereas any structural flexibilities are not taken into consideration. Results from the first task indicate that certain commonly used simplifications in the equations of motions result in unstable attitude control systems, when used for highly asymmetric spacecraft configurations. An approach is suggested circumventing this problem. Additionally, even though preliminary results from the second task are encouraging, the proposed nonlinear control system design method requires further investigation prior to its application and use as an effective payload pointing system design technique.

  5. Tensiomyography, sonoelastography, and mechanosensitivity differences between active, latent, and control low back myofascial trigger points

    PubMed Central

    Calvo-Lobo, César; Diez-Vega, Ignacio; Martínez-Pascual, Beatriz; Fernández-Martínez, Silvia; de la Cueva-Reguera, Mónica; Garrosa-Martín, Gerson; Rodríguez-Sanz, David

    2017-01-01

    Abstract The myofascial pain syndrome (MPS) is considered the most common musculoskeletal condition. The lumbopelvic pain (LPP) is established as one of the most prevalent musculoskeletal disorders. Nevertheless, previous research has not yet studied the contractibility changes by tensiomyography between myofascial trigger point (MTrP) types and normal tissue. Therefore, the aim of this study was to determine the tensiomyography, sonoelastography, and pressure pain threshold (PPT) differences between the palpation area of active and latent MTrPs with regards to control points in the lumbar erector spinae muscles of subjects with LPP. A cross-sectional descriptive study was performed. A convenience sample of 60 points (20 active MTrPs, 20 latent MTrPs, and 20 control points) was registered bilaterally in the lumbar erector spinae muscles from subjects with nonspecific LPP. The palpation order of active MTrPs, latent MTrPs, or control points was randomized for each side. The outcome assessors were blinded to the order or point type. The outcome measurements order for each point was sonoelastography manual strain index, tensiomyography, and PPT, separated by 15 minutes. Five contractile objective parameters were: maximal radial displacement (Dm), contraction time (Tc), sustain time (Ts), delay time (Td), and half-relaxation time (Tr). Tensiomyography parameters did not show any statistically significant difference (P > 0.05) between active MTrPs, latent MTrPs, and control points. Nevertheless, PPT and sonoelastography showed statistically significant differences (P < 0.05) between all point types, except for active and latent MTrPs PPT comparison (P = 0.091). Regarding the active MTrPs, a moderate positive correlation was observed between PPT and Dm (P = 0.047; τB = 0.450). Considering the control points, a moderate positive correlation was shown between sonoelastography and Td (P = 0.044; τB = 0.328). The tensiomyography contractile

  6. Abnormal proactive and reactive cognitive control during conflict processing in major depression.

    PubMed

    Vanderhasselt, Marie-Anne; De Raedt, Rudi; De Paepe, Annick; Aarts, Kristien; Otte, Georges; Van Dorpe, Jan; Pourtois, Gilles

    2014-02-01

    According to the Dual Mechanisms of Control framework, cognitive control consists of two complementary components: proactive control refers to anticipatory maintenance of goal-relevant information, whereas reactive control acts as a correction mechanism that is activated when a conflict occurs. Possibly, the well-known diminished inhibitory control in response to negative stimuli in Major Depressive Disorder (MDD) patients stems from a breakdown in proactive control, and/or anomalies in reactive cognitive control. In our study, MDD patients specifically showed increased response latencies when actively inhibiting a dominant response to a sad compared with a happy face. This condition was associated with a longer duration of a dominant ERP topography (800-900 ms poststimulus onset) and a stronger activity in the bilateral dorsal anterior cingulate cortex, reflecting abnormal reactive control when inhibiting attention to a negative stimulus. Moreover, MDD patients showed abnormalities in proactive cognitive control when preparing for the upcoming imperative stimulus (abnormal modulation of the contingent negative variation component), accompanied by more activity in brain regions belonging to the default mode network. All together, deficits to inhibit attention to negative information in MDD might originate from an abnormal use of both proactive resources and reactive control processes.

  7. CMG-induced LST dynamics. [application of control moment gyroscope to pointing and control systems of large space telescope

    NASA Technical Reports Server (NTRS)

    Seltzer, S. M.

    1974-01-01

    The application of control moment gyroscopes to the pointing and control system of the large space telescope is discussed. The parameter plane analysis technique is used to present the nonlinearity representing the control moment gyroscope gimbal bearing friction. The technique affords both analytic and graphic portrayal of the effects of variations is selected system parameters. Diagrams of the systems involved in the tests are presented.

  8. Reducing Pointing Errors During Cassini Reaction Control System Orbit Trim Maneuvers

    NASA Technical Reports Server (NTRS)

    Rizvi, Farheen

    2013-01-01

    The effect of altering a gain parameter in the Cassini reaction control system (RCS) delta-V controller on the maneuver execution errors during orbit trim maneuvers (OTMs) is explored. Cassini consists of two reaction control thruster branches (A & B) each with eight thrusters. Currently, the B-branch is operational while the A-branch serves as a back-up. The four Z-thrusters control the X and Y-axes, while the four Y-thrusters control the Z-axis. During an OTM, the Z-thrusters fire to maintain the X and Y-axes pointing within an attitude control dead-zone (-10 to 10 milliradians). The errors do not remain at zero due to pointing error sources such as spacecraft center of mass offset from the geometric center of the Z-facing thrusters, and variability in the thruster forces due to the thruster hardware differences. The delta-V reaction control system (RCS) controller ensures that the attitude error remains within this dead-zone. Gain parameters within the RCS delta-V controller affect the maneuver execution errors. Different parameter values are used to explore effect on these errors. It is found that pointing error decreases and magnitude error increases rapidly for gain parameters 10 times greater than the current parameter values used in the flight software.

  9. Acquisition Tracking and Pointing Control of the Bifocal Relay Mirror Spacecraft

    NASA Astrophysics Data System (ADS)

    Romano, Marcello; Agrawal, Brij N.

    This spacecraft consists of two large gimbaled telescopes, that are optically coupled and used to redirect a laser beam from a ground-based or spacecraft based source to a distant point on the earth or in space. The attitude control system consists of reaction wheels, star trackers and gyros. The optical control system consists of two fast steering mirrors and two optical tracker sensors. The very tight pointing and jitter requirements, together with the multi-body nature of the spacecraft, make the acquisition, tracking and pointing control very challenging. The control techniques developed in this research can be applied to imaging spacecrafts and spacecrafts with optical communications. numerical simulations. The simulations were performed to analyze two different control approaches proposed for the tracking and pointing of the Bifocal Relay Mirror spacecraft during operational phase. In the first control option considered, feed forward and feedback control are used for the spacecraft attitude control, while independent feedback is used by the optical subsystem in order to compensate the pointing error of the spacecraft. In the second control approach, the spacecraft and optical control systems are integrated. In case of uncertainty in target position and use of realistic sensors, using star tracker and rate gyros with Kalman Filter, the integrated control provides better performance. dynamics and control simulator of the Spacecraft Research and Design Center of Naval Postgraduate School. The attitude of this spherical air bearing based test-bed was controlled by three reaction wheels, while its attitude and angular velocity were sensed by an optical attitude sensor and three rate gyros, respectively. The three axes simulator platform included as payload a fully functional model of the transmitter section of the Bifocal Relay Mirror Spacecraft, consisting in one telescope with fast steering mirror and one optical tracker sensor. Two preliminary experiments have

  10. The Hubble Space Telescope fine guidance system operating in the coarse track pointing control mode

    NASA Technical Reports Server (NTRS)

    Whittlesey, Richard

    1993-01-01

    The Hubble Space Telescope (HST) Fine Guidance System has set new standards in pointing control capability for earth orbiting spacecraft. Two precision pointing control modes are implemented in the Fine Guidance System; one being a Coarse Track Mode which employs a pseudo-quadrature detector approach and the second being a Fine Mode which uses a two axis interferometer implementation. The Coarse Track Mode was designed to maintain FGS pointing error to within 20 milli-arc seconds (rms) when guiding on a 14.5 Mv star. The Fine Mode was designed to maintain FGS pointing error to less than 3 milli-arc seconds (rms). This paper addresses the HST FGS operating in the Coarse Track Mode. An overview of the implementation, the operation, and both the predicted and observed on orbit performance is presented. The discussion includes a review of the Fine Guidance System hardware which uses two beam steering Star Selector servos, four photon counting photomultiplier tube detectors, as well as a 24 bit microprocessor, which executes the control system firmware. Unanticipated spacecraft operational characteristics are discussed as they impact pointing performance. These include the influence of spherically aberrated star images as well as the mechanical shocks induced in the spacecraft during and following orbital day/night terminator crossings. Computer modeling of the Coarse Track Mode verifies the observed on orbit performance trends in the presence of these optical and mechanical disturbances. It is concluded that the coarse track pointing control function is performing as designed and is providing a robust pointing control capability for the Hubble Space Telescope.

  11. Nested task constraints shape continuous perception-action coupling control during human locomotor pointing.

    PubMed

    Renshaw, Ian; Davids, Keith

    2004-10-14

    Behavioural studies of human locomotor pointing have been dominated by specific task constraints of generating maximal approach velocity towards spatial targets. To examine locomotor pointing under different nested task constraints, at sub-maximal approach velocities and with concomitant differences in speed-accuracy trade offs, run-ups of professional cricket bowlers (n = 6) were analysed. Inter- and intra-trial analyses of step length adjustments revealed how differences between current and required locomotor pointing behaviour constrained visual adaptations of gait. Results supported a continuous perception-action coupling control mechanism, although no relationship was observed between step number in sequence and total amount of adjustment made, implying that visual adaptations did not continue to the end of a run-up once initiated. Rather, bowlers made step adjustments throughout the run-up, with strong associations for amount of adjustment made and amount needed. Significant variations were observed in inter-individual strategies for making most adjustments at different points of the run-up. A key premise of prospective control models of locomotor pointing was found to be robust, since regulation of cricketer's gait was continuous and based on perception of current and required behaviour. Findings extend understanding of the nature and range of nested task constraints under which perception-action coupling controls locomotor pointing performance.

  12. Pointing and Scanning Control of Optical Instruments using Rotating Unbalanced Masses

    NASA Technical Reports Server (NTRS)

    Bishop, Carlee A.; Hung, John Y.; Polites, Michael E.; Alhorn, Dean C.

    1996-01-01

    Correct pointing direction and scanning motions are essential in the operation of many flight payloads, such as balloon-borne telescopes and space-based X- ray and gamma-ray telescopes. Rotating unbalanced mass (RUM) devices have been recently proposed, implemented and successfully tested to produce a variety of scanning motions. Linear scans, raster scans, and circular scans have been successfully generated on a gimbaled payload using pairs of RUM devices. Theoretical analysis, computer simulations, and experiments have also been used to study the feasibility of using RUM devices to control instrument pointing direction, in addition to generating scanning motion. Dynamic modeling of a gimbaled payload equipped with a pair of RUM devices has been studied, and preliminary testing indicates that the pointing control is indeed feasible. However, there is also great potential for significant performance improvements through more advanced control system analysis, modeling and design. In this paper, modeling and control methods are described to achieve simultaneous scanning and pointing control of a gimbaled payload using rotating unbalance mass (RUM) devices. The model development work builds upon the results of Polites et al. and also some modeling approaches from robotics research. Results of some preliminary experiments are discussed and some nonlinear control methods will be proposed.

  13. An approach to versatile highly-uniform MOVPE growth: the flow controlled stagnation point flow reactor

    NASA Astrophysics Data System (ADS)

    Kondo, Makoto; Kuramata, Akito; Fujii, Takuya; Anayama, Chikashi; Okazaki, Jiro; Sekiguchi, Hiroshi; Tanahashi, Toshiyuki; Yamazaki, Susumu; Nakajima, Kazuo

    1992-11-01

    We present an approach to versatile highly-uniform MOVPE growth using the controlled stagnation point flow reactor. Our approach for uniform growth involves two concepts: (1) realizing the stagnation point flow condition in a vertical reactor configuration and (2) introducing a method for versatile flow-field control using the flow-controlled multiple gas-injector technique. The versatility of the flow-control technique was investigated by evaluating how radial deposition rate uniformity is affected by variation in several hydrodynamic and reactor configuration factors: the inlet flow rate, operating pressure, susceptor temperature, susceptor rotation speed, and the inlet and susceptor separation. We confirmed that a spatially uniform deposition rate can be obtained over a wide range of hydrodynamic and configuration parameters, demonstrating that the flow-control technique can provide a stable stagnation point flow field. Even when the ideal stagnation point flow-field is disturbed, for example, by high temperature susceptor heating, it could be completely compensated by adjusting the flow rate ratio for multiple injectors, showing our technique's ability to control flow-fields. By using this technique, we obtained excellent uniformities in both layer thickness and alloy composition for two important materials - GaInAsP and AlGaInP - in the same reactor.

  14. Single supplier single retailer inventory model controlled by the reorder and shipping points with sharing information

    NASA Astrophysics Data System (ADS)

    Ho, Wen-Tsung; Hsiao, Yu-Cheng

    2012-04-01

    This study investigated the integrated stochastic inventory problem for a two-stage supply chain consisting of a single retailer and a single supplier. By using batch shipment policy, the expected total cost can be significantly reduced. An equally sized batch shipment model, controlled by both the reorder and shipping points, with sharing information by enterprise resource planning and radio frequency identification is constructed. The problem is solved optimally by the proposed algorithm that determines the economic lot size, the optimal batch sizes and number of batches. A numerical example is included to illustrate the algorithmic procedures and to prove that the model controlled both by the reorder and shipping points is superior to the classic model controlled only by the reorder point.

  15. The Control Point Library Building System. [for Landsat MSS and RBV geometric image correction

    NASA Technical Reports Server (NTRS)

    Niblack, W.

    1981-01-01

    The Earth Resources Observation System (EROS) Data Center in Sioux Falls, South Dakota distributes precision corrected Landsat MSS and RBV data. These data are derived from master data tapes produced by the Master Data Processor (MDP), NASA's system for computing and applying corrections to the data. Included in the MDP is the Control Point Library Building System (CPLBS), an interactive, menu-driven system which permits a user to build and maintain libraries of control points. The control points are required to achieve the high geometric accuracy desired in the output MSS and RBV data. This paper describes the processing performed by CPLBS, the accuracy of the system, and the host computer and special image viewing equipment employed.

  16. Precision Pointing Control System (PPCS) system design and analysis. [for gimbaled experiment platforms

    NASA Technical Reports Server (NTRS)

    Frew, A. M.; Eisenhut, D. F.; Farrenkopf, R. L.; Gates, R. F.; Iwens, R. P.; Kirby, D. K.; Mann, R. J.; Spencer, D. J.; Tsou, H. S.; Zaremba, J. G.

    1972-01-01

    The precision pointing control system (PPCS) is an integrated system for precision attitude determination and orientation of gimbaled experiment platforms. The PPCS concept configures the system to perform orientation of up to six independent gimbaled experiment platforms to design goal accuracy of 0.001 degrees, and to operate in conjunction with a three-axis stabilized earth-oriented spacecraft in orbits ranging from low altitude (200-2500 n.m., sun synchronous) to 24 hour geosynchronous, with a design goal life of 3 to 5 years. The system comprises two complementary functions: (1) attitude determination where the attitude of a defined set of body-fixed reference axes is determined relative to a known set of reference axes fixed in inertial space; and (2) pointing control where gimbal orientation is controlled, open-loop (without use of payload error/feedback) with respect to a defined set of body-fixed reference axes to produce pointing to a desired target.

  17. 47 CFR 90.473 - Operation of internal transmitter control systems through licensed fixed control points.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Operation of internal transmitter control... COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control Internal Transmitter Control Systems § 90.473 Operation of internal transmitter...

  18. 47 CFR 90.473 - Operation of internal transmitter control systems through licensed fixed control points.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Operation of internal transmitter control... COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control Internal Transmitter Control Systems § 90.473 Operation of internal transmitter...

  19. 47 CFR 90.473 - Operation of internal transmitter control systems through licensed fixed control points.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Operation of internal transmitter control... COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control Internal Transmitter Control Systems § 90.473 Operation of internal transmitter...

  20. Compound control method of neutral point voltage of three level NPC inverter based on the vector method of virtual space and hysteresis control

    NASA Astrophysics Data System (ADS)

    Yang, Fengping; Xiao, Fangfei

    2017-03-01

    Current control methods include hardware control and software control corresponding to the inherent unbalance problem of neutral point voltage in three level NPC inverter. The hardware control is rarely used due to its high cost. In this paper, a new compound control method has been presented based on the vector method of virtual space and traditional hysteresis control of neutral point voltage, which can make up the shortcoming of the virtual control without the feedback control system of neutral point voltage and the blind area of hysteresis control and control the deviation and wave of neutral point voltage. The accuracy of this method has been demonstrated by simulation.

  1. The Major Genetic Determinants of HIV-1 Control Affect HLA Class I Peptide Presentation

    PubMed Central

    Pereyra, Florencia; Jia, Xiaoming; McLaren, Paul J.; Telenti, Amalio; de Bakker, Paul I.W.; Walker, Bruce D.; Jia, Xiaoming; McLaren, Paul J.; Ripke, Stephan; Brumme, Chanson J.; Pulit, Sara L.; Telenti, Amalio; Carrington, Mary; Kadie, Carl M.; Carlson, Jonathan M.; Heckerman, David; de Bakker, Paul I.W.; Pereyra, Florencia; de Bakker, Paul I.W.; Graham, Robert R.; Plenge, Robert M.; Deeks, Steven G.; Walker, Bruce D.; Gianniny, Lauren; Crawford, Gabriel; Sullivan, Jordan; Gonzalez, Elena; Davies, Leela; Camargo, Amy; Moore, Jamie M.; Beattie, Nicole; Gupta, Supriya; Crenshaw, Andrew; Burtt, Noël P.; Guiducci, Candace; Gupta, Namrata; Carrington, Mary; Gao, Xiaojiang; Qi, Ying; Yuki, Yuko; Pereyra, Florencia; Piechocka-Trocha, Alicja; Cutrell, Emily; Rosenberg, Rachel; Moss, Kristin L.; Lemay, Paul; O’Leary, Jessica; Schaefer, Todd; Verma, Pranshu; Toth, Ildiko; Block, Brian; Baker, Brett; Rothchild, Alissa; Lian, Jeffrey; Proudfoot, Jacqueline; Alvino, Donna Marie L.; Vine, Seanna; Addo, Marylyn M.; Allen, Todd M.; Altfeld, Marcus; Henn, Matthew R.; Le Gall, Sylvie; Streeck, Hendrik; Walker, Bruce D.; Haas, David W.; Kuritzkes, Daniel R.; Robbins, Gregory K.; Shafer, Robert W.; Gulick, Roy M.; Shikuma, Cecilia M.; Haubrich, Richard; Riddler, Sharon; Sax, Paul E.; Daar, Eric S.; Ribaudo, Heather J.; Agan, Brian; Agarwal, Shanu; Ahern, Richard L.; Allen, Brady L.; Altidor, Sherly; Altschuler, Eric L.; Ambardar, Sujata; Anastos, Kathryn; Anderson, Ben; Anderson, Val; Andrady, Ushan; Antoniskis, Diana; Bangsberg, David; Barbaro, Daniel; Barrie, William; Bartczak, J.; Barton, Simon; Basden, Patricia; Basgoz, Nesli; Bazner, Suzane; Bellos, Nicholaos C.; Benson, Anne M.; Berger, Judith; Bernard, Nicole F.; Bernard, Annette M.; Birch, Christopher; Bodner, Stanley J.; Bolan, Robert K.; Boudreaux, Emilie T.; Bradley, Meg; Braun, James F.; Brndjar, Jon E.; Brown, Stephen J.; Brown, Katherine; Brown, Sheldon T.; Burack, Jedidiah; Bush, Larry M.; Cafaro, Virginia; Campbell, Omobolaji; Campbell, John; Carlson, Robert H.; Carmichael, J. Kevin; Casey, Kathleen K.; Cavacuiti, Chris; Celestin, Gregory; Chambers, Steven T.; Chez, Nancy; Chirch, Lisa M.; Cimoch, Paul J.; Cohen, Daniel; Cohn, Lillian E.; Conway, Brian; Cooper, David A.; Cornelson, Brian; Cox, David T.; Cristofano, Michael V.; Cuchural, George; Czartoski, Julie L.; Dahman, Joseph M.; Daly, Jennifer S.; Davis, Benjamin T.; Davis, Kristine; Davod, Sheila M.; Deeks, Steven G.; DeJesus, Edwin; Dietz, Craig A.; Dunham, Eleanor; Dunn, Michael E.; Ellerin, Todd B.; Eron, Joseph J.; Fangman, John J.W.; Farel, Claire E.; Ferlazzo, Helen; Fidler, Sarah; Fleenor-Ford, Anita; Frankel, Renee; Freedberg, Kenneth A.; French, Neel K.; Fuchs, Jonathan D.; Fuller, Jon D.; Gaberman, Jonna; Gallant, Joel E.; Gandhi, Rajesh T.; Garcia, Efrain; Garmon, Donald; Gathe, Joseph C.; Gaultier, Cyril R.; Gebre, Wondwoosen; Gilman, Frank D.; Gilson, Ian; Goepfert, Paul A.; Gottlieb, Michael S.; Goulston, Claudia; Groger, Richard K.; Gurley, T. Douglas; Haber, Stuart; Hardwicke, Robin; Hardy, W. David; Harrigan, P. Richard; Hawkins, Trevor N.; Heath, Sonya; Hecht, Frederick M.; Henry, W. Keith; Hladek, Melissa; Hoffman, Robert P.; Horton, James M.; Hsu, Ricky K.; Huhn, Gregory D.; Hunt, Peter; Hupert, Mark J.; Illeman, Mark L.; Jaeger, Hans; Jellinger, Robert M.; John, Mina; Johnson, Jennifer A.; Johnson, Kristin L.; Johnson, Heather; Johnson, Kay; Joly, Jennifer; Jordan, Wilbert C.; Kauffman, Carol A.; Khanlou, Homayoon; Killian, Robert K.; Kim, Arthur Y.; Kim, David D.; Kinder, Clifford A.; Kirchner, Jeffrey T.; Kogelman, Laura; Kojic, Erna Milunka; Korthuis, P. Todd; Kurisu, Wayne; Kwon, Douglas S.; LaMar, Melissa; Lampiris, Harry; Lanzafame, Massimiliano; Lederman, Michael M.; Lee, David M.; Lee, Jean M.L.; Lee, Marah J.; Lee, Edward T.Y.; Lemoine, Janice; Levy, Jay A.; Llibre, Josep M.; Liguori, Michael A.; Little, Susan J.; Liu, Anne Y.; Lopez, Alvaro J.; Loutfy, Mono R.; Loy, Dawn; Mohammed, Debbie Y.; Man, Alan; Mansour, Michael K.; Marconi, Vincent C.; Markowitz, Martin; Marques, Rui; Martin, Jeffrey N.; Martin, Harold L.; Mayer, Kenneth Hugh; McElrath, M. Juliana; McGhee, Theresa A.; McGovern, Barbara H.; McGowan, Katherine; McIntyre, Dawn; Mcleod, Gavin X.; Menezes, Prema; Mesa, Greg; Metroka, Craig E.; Meyer-Olson, Dirk; Miller, Andy O.; Montgomery, Kate; Mounzer, Karam C.; Nagami, Ellen H.; Nagin, Iris; Nahass, Ronald G.; Nelson, Margret O.; Nielsen, Craig; Norene, David L.; O’Connor, David H.; Ojikutu, Bisola O.; Okulicz, Jason; Oladehin, Olakunle O.; Oldfield, Edward C.; Olender, Susan A.; Ostrowski, Mario; Owen, William F.; Pae, Eunice; Parsonnet, Jeffrey; Pavlatos, Andrew M.; Perlmutter, Aaron M.; Pierce, Michael N.; Pincus, Jonathan M.; Pisani, Leandro; Price, Lawrence Jay; Proia, Laurie; Prokesch, Richard C.; Pujet, Heather Calderon; Ramgopal, Moti; Rathod, Almas; Rausch, Michael; Ravishankar, J.; Rhame, Frank S.; Richards, Constance Shamuyarira; Richman, Douglas D.; Robbins, Gregory K.; Rodes, Berta; Rodriguez, Milagros; Rose, Richard C.; Rosenberg, Eric S.; Rosenthal, Daniel; Ross, Polly E.; Rubin, David S.; Rumbaugh, Elease; Saenz, Luis; Salvaggio, Michelle R.; Sanchez, William C.; Sanjana, Veeraf M.; Santiago, Steven; Schmidt, Wolfgang; Schuitemaker, Hanneke; Sestak, Philip M.; Shalit, Peter; Shay, William; Shirvani, Vivian N.; Silebi, Vanessa I.; Sizemore, James M.; Skolnik, Paul R.; Sokol-Anderson, Marcia; Sosman, James M.; Stabile, Paul; Stapleton, Jack T.; Starrett, Sheree; Stein, Francine; Stellbrink, Hans-Jurgen; Sterman, F. Lisa; Stone, Valerie E.; Stone, David R.; Tambussi, Giuseppe; Taplitz, Randy A.; Tedaldi, Ellen M.; Telenti, Amalio; Theisen, William; Torres, Richard; Tosiello, Lorraine; Tremblay, Cecile; Tribble, Marc A.; Trinh, Phuong D.; Tsao, Alice; Ueda, Peggy; Vaccaro, Anthony; Valadas, Emilia; Vanig, Thanes J.; Vecino, Isabel; Vega, Vilma M.; Veikley, Wenoah; Wade, Barbara H.; Walworth, Charles; Wanidworanun, Chingchai; Ward, Douglas J.; Warner, Daniel A.; Weber, Robert D.; Webster, Duncan; Weis, Steve; Wheeler, David A.; White, David J.; Wilkins, Ed; Winston, Alan; Wlodaver, Clifford G.; Wout, Angelique van’t; Wright, David P.; Yang, Otto O.; Yurdin, David L.; Zabukovic, Brandon W.; Zachary, Kimon C.; Zeeman, Beth; Zhao, Meng

    2011-01-01

    Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA–viral peptide interaction as the major factor modulating durable control of HIV infection. PMID:21051598

  2. The major genetic determinants of HIV-1 control affect HLA class I peptide presentation.

    PubMed

    Pereyra, Florencia; Jia, Xiaoming; McLaren, Paul J; Telenti, Amalio; de Bakker, Paul I W; Walker, Bruce D; Ripke, Stephan; Brumme, Chanson J; Pulit, Sara L; Carrington, Mary; Kadie, Carl M; Carlson, Jonathan M; Heckerman, David; Graham, Robert R; Plenge, Robert M; Deeks, Steven G; Gianniny, Lauren; Crawford, Gabriel; Sullivan, Jordan; Gonzalez, Elena; Davies, Leela; Camargo, Amy; Moore, Jamie M; Beattie, Nicole; Gupta, Supriya; Crenshaw, Andrew; Burtt, Noël P; Guiducci, Candace; Gupta, Namrata; Gao, Xiaojiang; Qi, Ying; Yuki, Yuko; Piechocka-Trocha, Alicja; Cutrell, Emily; Rosenberg, Rachel; Moss, Kristin L; Lemay, Paul; O'Leary, Jessica; Schaefer, Todd; Verma, Pranshu; Toth, Ildiko; Block, Brian; Baker, Brett; Rothchild, Alissa; Lian, Jeffrey; Proudfoot, Jacqueline; Alvino, Donna Marie L; Vine, Seanna; Addo, Marylyn M; Allen, Todd M; Altfeld, Marcus; Henn, Matthew R; Le Gall, Sylvie; Streeck, Hendrik; Haas, David W; Kuritzkes, Daniel R; Robbins, Gregory K; Shafer, Robert W; Gulick, Roy M; Shikuma, Cecilia M; Haubrich, Richard; Riddler, Sharon; Sax, Paul E; Daar, Eric S; Ribaudo, Heather J; Agan, Brian; Agarwal, Shanu; Ahern, Richard L; Allen, Brady L; Altidor, Sherly; Altschuler, Eric L; Ambardar, Sujata; Anastos, Kathryn; Anderson, Ben; Anderson, Val; Andrady, Ushan; Antoniskis, Diana; Bangsberg, David; Barbaro, Daniel; Barrie, William; Bartczak, J; Barton, Simon; Basden, Patricia; Basgoz, Nesli; Bazner, Suzane; Bellos, Nicholaos C; Benson, Anne M; Berger, Judith; Bernard, Nicole F; Bernard, Annette M; Birch, Christopher; Bodner, Stanley J; Bolan, Robert K; Boudreaux, Emilie T; Bradley, Meg; Braun, James F; Brndjar, Jon E; Brown, Stephen J; Brown, Katherine; Brown, Sheldon T; Burack, Jedidiah; Bush, Larry M; Cafaro, Virginia; Campbell, Omobolaji; Campbell, John; Carlson, Robert H; Carmichael, J Kevin; Casey, Kathleen K; Cavacuiti, Chris; Celestin, Gregory; Chambers, Steven T; Chez, Nancy; Chirch, Lisa M; Cimoch, Paul J; Cohen, Daniel; Cohn, Lillian E; Conway, Brian; Cooper, David A; Cornelson, Brian; Cox, David T; Cristofano, Michael V; Cuchural, George; Czartoski, Julie L; Dahman, Joseph M; Daly, Jennifer S; Davis, Benjamin T; Davis, Kristine; Davod, Sheila M; DeJesus, Edwin; Dietz, Craig A; Dunham, Eleanor; Dunn, Michael E; Ellerin, Todd B; Eron, Joseph J; Fangman, John J W; Farel, Claire E; Ferlazzo, Helen; Fidler, Sarah; Fleenor-Ford, Anita; Frankel, Renee; Freedberg, Kenneth A; French, Neel K; Fuchs, Jonathan D; Fuller, Jon D; Gaberman, Jonna; Gallant, Joel E; Gandhi, Rajesh T; Garcia, Efrain; Garmon, Donald; Gathe, Joseph C; Gaultier, Cyril R; Gebre, Wondwoosen; Gilman, Frank D; Gilson, Ian; Goepfert, Paul A; Gottlieb, Michael S; Goulston, Claudia; Groger, Richard K; Gurley, T Douglas; Haber, Stuart; Hardwicke, Robin; Hardy, W David; Harrigan, P Richard; Hawkins, Trevor N; Heath, Sonya; Hecht, Frederick M; Henry, W Keith; Hladek, Melissa; Hoffman, Robert P; Horton, James M; Hsu, Ricky K; Huhn, Gregory D; Hunt, Peter; Hupert, Mark J; Illeman, Mark L; Jaeger, Hans; Jellinger, Robert M; John, Mina; Johnson, Jennifer A; Johnson, Kristin L; Johnson, Heather; Johnson, Kay; Joly, Jennifer; Jordan, Wilbert C; Kauffman, Carol A; Khanlou, Homayoon; Killian, Robert K; Kim, Arthur Y; Kim, David D; Kinder, Clifford A; Kirchner, Jeffrey T; Kogelman, Laura; Kojic, Erna Milunka; Korthuis, P Todd; Kurisu, Wayne; Kwon, Douglas S; LaMar, Melissa; Lampiris, Harry; Lanzafame, Massimiliano; Lederman, Michael M; Lee, David M; Lee, Jean M L; Lee, Marah J; Lee, Edward T Y; Lemoine, Janice; Levy, Jay A; Llibre, Josep M; Liguori, Michael A; Little, Susan J; Liu, Anne Y; Lopez, Alvaro J; Loutfy, Mono R; Loy, Dawn; Mohammed, Debbie Y; Man, Alan; Mansour, Michael K; Marconi, Vincent C; Markowitz, Martin; Marques, Rui; Martin, Jeffrey N; Martin, Harold L; Mayer, Kenneth Hugh; McElrath, M Juliana; McGhee, Theresa A; McGovern, Barbara H; McGowan, Katherine; McIntyre, Dawn; Mcleod, Gavin X; Menezes, Prema; Mesa, Greg; Metroka, Craig E; Meyer-Olson, Dirk; Miller, Andy O; Montgomery, Kate; Mounzer, Karam C; Nagami, Ellen H; Nagin, Iris; Nahass, Ronald G; Nelson, Margret O; Nielsen, Craig; Norene, David L; O'Connor, David H; Ojikutu, Bisola O; Okulicz, Jason; Oladehin, Olakunle O; Oldfield, Edward C; Olender, Susan A; Ostrowski, Mario; Owen, William F; Pae, Eunice; Parsonnet, Jeffrey; Pavlatos, Andrew M; Perlmutter, Aaron M; Pierce, Michael N; Pincus, Jonathan M; Pisani, Leandro; Price, Lawrence Jay; Proia, Laurie; Prokesch, Richard C; Pujet, Heather Calderon; Ramgopal, Moti; Rathod, Almas; Rausch, Michael; Ravishankar, J; Rhame, Frank S; Richards, Constance Shamuyarira; Richman, Douglas D; Rodes, Berta; Rodriguez, Milagros; Rose, Richard C; Rosenberg, Eric S; Rosenthal, Daniel; Ross, Polly E; Rubin, David S; Rumbaugh, Elease; Saenz, Luis; Salvaggio, Michelle R; Sanchez, William C; Sanjana, Veeraf M; Santiago, Steven; Schmidt, Wolfgang; Schuitemaker, Hanneke; Sestak, Philip M; Shalit, Peter; Shay, William; Shirvani, Vivian N; Silebi, Vanessa I; Sizemore, James M; Skolnik, Paul R; Sokol-Anderson, Marcia; Sosman, James M; Stabile, Paul; Stapleton, Jack T; Starrett, Sheree; Stein, Francine; Stellbrink, Hans-Jurgen; Sterman, F Lisa; Stone, Valerie E; Stone, David R; Tambussi, Giuseppe; Taplitz, Randy A; Tedaldi, Ellen M; Telenti, Amalio; Theisen, William; Torres, Richard; Tosiello, Lorraine; Tremblay, Cecile; Tribble, Marc A; Trinh, Phuong D; Tsao, Alice; Ueda, Peggy; Vaccaro, Anthony; Valadas, Emilia; Vanig, Thanes J; Vecino, Isabel; Vega, Vilma M; Veikley, Wenoah; Wade, Barbara H; Walworth, Charles; Wanidworanun, Chingchai; Ward, Douglas J; Warner, Daniel A; Weber, Robert D; Webster, Duncan; Weis, Steve; Wheeler, David A; White, David J; Wilkins, Ed; Winston, Alan; Wlodaver, Clifford G; van't Wout, Angelique; Wright, David P; Yang, Otto O; Yurdin, David L; Zabukovic, Brandon W; Zachary, Kimon C; Zeeman, Beth; Zhao, Meng

    2010-12-10

    Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection.

  3. A multiobjective model for non-point source pollution control for an off-stream reservoir catchment.

    PubMed

    Kao, J J; Chen, W J

    2003-01-01

    Phosphorus loads from agricultural non-point source pollution (NPSP) significantly degrade reservoir water quality, making adequate control of agricultural NPSP necessary for improving the water quality. Controlling NPSP is generally accomplished using various Best Management Practices (BMPs). The present study applies the Agricultural Non-Point Source Pollution (AGNPS) model to simulate NPSP loading and BMP efficiencies and establishes an enhanced multiobjective mixed-integer programming model for NPSP control strategy analyses based on these results. Cost, phosphorus load, sediment load and equity are the four major objectives considered. A case study for the Posan reservoir is presented. Four commonly proposed and applicable BMPs are chosen. Non-inferior solutions obtained using the constraint method and trade-off relationships among different control objectives are described and discussed. Compared with a previously proposed fertilizer control model, results show that the model established herein is more cost-effective and achieves better phosphorus and sediment loading reduction and equity goals. Furthermore, the current model is expected to facilitate decision-making analysis for development of an appropriate cost-sharing program to encourage adoption of appropriate BMPs by farmers.

  4. Point defect reduction in wide bandgap semiconductors by defect quasi Fermi level control

    NASA Astrophysics Data System (ADS)

    Reddy, P.; Hoffmann, M. P.; Kaess, F.; Bryan, Z.; Bryan, I.; Bobea, M.; Klump, A.; Tweedie, J.; Kirste, R.; Mita, S.; Gerhold, M.; Collazo, R.; Sitar, Z.

    2016-11-01

    A theoretical framework for a general approach to reduce point defect density in materials via control of defect quasi Fermi level (dQFL) is presented. The control of dQFL is achieved via excess minority carrier generation. General guidelines for controlling dQFL that lead to a significant reduction in compensating point defects in any doped material is proposed. The framework introduces and incorporates the effects of various factors that control the efficacy of the defect reduction process such as defect level, defect formation energy, bandgap, and excess minority carrier density. Modified formation energy diagrams are proposed, which illustrate the effect of the quasi Fermi level control on the defect formation energies. These formation energy diagrams provide powerful tools to determine the feasibility and requirements to produce the desired reduction in specified point defects. An experimental study of the effect of excess minority carriers on point defect incorporation in GaN and AlGaN shows an excellent quantitative agreement with the theoretical predictions. Illumination at energies larger than the bandgap is employed as a means to generate excess minority carriers. The case studies with CN in Si doped GaN, H and VN in Mg doped GaN and VM-2ON in Si doped Al0.65Ga0.35N revealed a significant reduction in impurities in agreement with the proposed theory. Since compensating point defects control the material performance (this is particularly challenging in wide and ultra wide bandgap materials), dQFL control is a highly promising technique with wide scope and may be utilized to improve the properties of various materials systems and performance of devices based upon them.

  5. Optimal control problems with switching points. Ph.D. Thesis, 1990 Final Report

    NASA Technical Reports Server (NTRS)

    Seywald, Hans

    1991-01-01

    An overview is presented of the problems and difficulties that arise in solving optimal control problems with switching points. A brief discussion of existing optimality conditions is given and a numerical approach for solving the multipoint boundary value problems associated with the first-order necessary conditions of optimal control is presented. Two real-life aerospace optimization problems are treated explicitly. These are altitude maximization for a sounding rocket (Goddard Problem) in the presence of a dynamic pressure limit, and range maximization for a supersonic aircraft flying in the vertical, also in the presence of a dynamic pressure limit. In the second problem singular control appears along arcs with active dynamic pressure limit, which in the context of optimal control, represents a first-order state inequality constraint. An extension of the Generalized Legendre-Clebsch Condition to the case of singular control along state/control constrained arcs is presented and is applied to the aircraft range maximization problem stated above. A contribution to the field of Jacobi Necessary Conditions is made by giving a new proof for the non-optimality of conjugate paths in the Accessory Minimum Problem. Because of its simple and explicit character, the new proof may provide the basis for an extension of Jacobi's Necessary Condition to the case of the trajectories with interior point constraints. Finally, the result that touch points cannot occur for first-order state inequality constraints is extended to the case of vector valued control functions.

  6. Complement receptor immunoglobulin: a control point in infection and immunity, inflammation and cancer.

    PubMed

    Small, Annabelle Grace; Al-Baghdadi, Marwah; Quach, Alex; Hii, Charles; Ferrante, Antonio

    2016-01-01

    The B7 family-related protein, V-set and Ig domain (VSIG4) / Z39Ig / complement receptor immunoglobulin (CRIg), is a new player in the regulation of immunity to infection and inflammation. The unique features of this receptor as compared with classical complement receptors, CR3 and CR4, have heralded the emergence of new concepts in the regulation of innate and adaptive immunity. Its selective expression in tissue macrophages and dendritic cells has been considered of importance in host defence and in maintaining tolerance against self-antigens. Although a major receptor for phagocytosis of complement opsonised bacteria, its array of emerging functions which incorporates the immune suppressive and anti-inflammatory action of the receptor have now been realised. Accumulating evidence from mouse experimental models indicates a potential role for CRIg in protection against bacterial infection and inflammatory diseases, such as rheumatoid arthritis, type 1 diabetes and systemic lupus erythematosus, and also in promotion of tumour growth. CRIg expression can be considered as a control point in these diseases, through which inflammatory mediators, including cytokines, act. The ability of CRIg to suppress cytotoxic T cell proliferation and function may underlie its promotion of cancer growth. Thus, the unique properties of this receptor open up new avenues for understanding of the pathways that regulate inflammation during infection, autoimmunity and cancer with the potential for new drug targets to be identified. While some complement receptors may be differently expressed in mice and humans, as well as displaying different properties, mouse CRIg has a structure and function similar to the human receptor, suggesting that extrapolation to human diseases is appropriate. Furthermore, there is emerging evidence in human conditions that CRIg may be a valuable biomarker in infection and immunity, inflammatory conditions and cancer prognosis.

  7. Double-blind, placebo-controlled evaluation of extended-release bupropion in elderly patients with major depressive disorder.

    PubMed

    Hewett, K; Chrzanowski, W; Jokinen, R; Felgentreff, R; Shrivastava, R K; Gee, M D; Wightman, D S; O'Leary, M C; Millen, L S; Leon, M C; Briggs, M A; Krishen, A; Modell, J G

    2010-04-01

    Major depressive disorder in the elderly is associated with increased morbidity and reduced quality of life. This 10 week, placebo-controlled study investigated the efficacy and tolerability of extended-release bupropion (150-300 mg once daily) in depressed patients aged 65 years or older. The statistical assumptions necessary for the validity of the protocol-specified analysis of covariance were not met for the analysis of the primary outcome variable (Montgomery-Asberg Depression Rating Scale total score at Week 10, last observation carried forward). Alternative statistical methods used for the analysis of this variable demonstrated statistical significance. Statistically significant improvements were observed on the majority of secondary end points when compared with placebo, including the health outcome measures for motivation and energy, and life satisfaction and contentment. Adverse events were generally mild to moderate and similar between treatment groups. This study demonstrated that the extended-release bupropion is an effective, well-tolerated treatment for major depression in the elderly.

  8. A Flexible VHDL Floating Point Module for Control Algorithm Implementation in Space Applications

    NASA Astrophysics Data System (ADS)

    Padierna, A.; Nicoleau, C.; Sanchez, J.; Hidalgo, I.; Elvira, S.

    2012-08-01

    The implementation of control loops for space applications is an area with great potential. However, the characteristics of this kind of systems, such as its wide dynamic range of numeric values, make inadequate the use of fixed-point algorithms.However, because the generic chips available for the treatment of floating point data are, in general, not qualified to operate in space environments and the possibility of using an IP module in a FPGA/ASIC qualified for space is not viable due to the low amount of logic cells available for these type of devices, it is necessary to find a viable alternative.For these reasons, in this paper a VHDL Floating Point Module is presented. This proposal allows the design and execution of floating point algorithms with acceptable occupancy to be implemented in FPGAs/ASICs qualified for space environments.

  9. Design and Implementation of a Digital Controller for a Vibration Isolation and Vernier Pointing System

    NASA Technical Reports Server (NTRS)

    Neff, Daniel J.; Britcher, Colin P.

    1996-01-01

    This paper discusses the recommissioning of the Annular Suspension and Pointing System (ASPS), originally developed in the mid 1970's for pointing and vibration isolation of space experiments. The hardware was developed for NASA Langley Research Center by Sperry Flight Systems (now Honeywell Satellite Systems), was delivered to NASA in 1983. Recently, the hardware was loaned to Old Dominion University (ODU). The ASPS includes coarse gimbal assemblies and a Vernier Pointing Assembly (VPA) that utilize magnetic suspension to provide noncontacting vibration isolation and vernier pointing of the payload. The VPA is the main focus of this research. At ODU, the system has been modified such that it can now be operated in a l-g environment without a gravity offload. Suspension of the annular iron rotor in five degrees-of-freedom has been achieved with the use of modern switching power amplifiers and a digital controller implemented on a 486-class PC.

  10. Sliding mode control of magnetic suspensions for precision pointing and tracking applications

    NASA Technical Reports Server (NTRS)

    Misovec, Kathleen M.; Flynn, Frederick J.; Johnson, Bruce G.; Hedrick, J. Karl

    1991-01-01

    A recently developed nonlinear control method, sliding mode control, is examined as a means of advancing the achievable performance of space-based precision pointing and tracking systems that use nonlinear magnetic actuators. Analytic results indicate that sliding mode control improves performance compared to linear control approaches. In order to realize these performance improvements, precise knowledge of the plant is required. Additionally, the interaction of an estimating scheme and the sliding mode controller has not been fully examined in the literature. Estimation schemes were designed for use with this sliding mode controller that do not seriously degrade system performance. The authors designed and built a laboratory testbed to determine the feasibility of utilizing sliding mode control in these types of applications. Using this testbed, experimental verification of the authors' analyses is ongoing.

  11. Future path and tangent point models in the visual control of locomotion in curve driving.

    PubMed

    Lappi, Otto

    2014-10-21

    Studying human behavior in the natural context of everyday visual tasks--including locomotor tasks such as driving--can reveal visual strategies or even suggest underlying visual mechanisms. This paper reviews empirical and theoretical work in the past 20 years (1994-2014) on the visual control of steering a vehicle along a winding path-one of the most comprehensively studied forms of visually guided locomotion in humans. The focus is on on-road studies of visual behavior and what they can reveal about the visual strategies in curve driving. Theoretical models and results from simulator studies are discussed where they have direct relevance to the interpretation of on-road data. For the past 20 years, the point of departure in studies of curve driving has been tangent point orientation, and tangent point models (models based on tracking the tangent point) have become established as the default account of how vision is used in curve negotiation. More recent studies have questioned the generality of the tangent point hypothesis, however, arguing that in addition to (or instead of) the tangent point, drivers target visual reference points on their future path. Ecological validity of real-world studies often comes at the cost of methodological challenges that make the data difficult to interpret in terms of underlying mechanisms, and the limitations of existing data and the complementary roles of real-world and laboratory studies are discussed.

  12. Effect of Confinement on the Bubble Points of Hydrocarbons in Controlled-Pore Glasses

    NASA Astrophysics Data System (ADS)

    Luo, Sheng; Lutkenhaus, Jodie; Nasrabadi, Hadi; Hadi Nasrabadi Team

    2015-03-01

    Phase behavior in shale remains a challenging problem in the petroleum industry due to many complexities. One complexity is the strong surface-fluid interactions in shale nano-scale pores. These interactions can lead to a heterogeneous distribution of molecules, which conventional bulk-phase thermodynamics fails to describe. Herein, we report a study on the bubble points of various hydrocarbons confined in nanoporous controlled-pore glasses of 4.3 to 38.1 nm pore diameter. Differential scanning calorimetry is used to measure the temperature at which the gas phase begins to form (i.e. bubble point). Besides pore diameter, the relative hydrocarbon loading in the controlled-pore glass is evaluated. The findings suggest that the bubble point is dramatically affected by pore diameter.

  13. Design Considerations for Miniaturized Control Moment Gyroscopes for Rapid Retargeting and Precision Pointing of Small Satellites

    NASA Technical Reports Server (NTRS)

    Patankar, Kunal; Fitz-Coy, Norman; Roithmayr, Carlos M.

    2014-01-01

    This paper presents the design as well as characterization of a practical control moment gyroscope (CMG) based attitude control system (ACS) for small satellites in the 15-20 kilogram mass range performing rapid retargeting and precision pointing maneuvers. The paper focuses on the approach taken in the design of miniaturized CMGs while considering the constraints imposed by the use of commercial off-the-shelf (COTS) components as well as the size of the satellite. It is shown that a hybrid mode is more suitable for COTS based moment exchange actuators; a mode that uses the torque amplification of CMGs for rapid retargeting and direct torque capabilities of the flywheel motors for precision pointing. A simulation is provided to demonstrate on-orbit slew and pointing performance.

  14. Radiation acquisition and RBF neural network analysis on BOF end-point control

    NASA Astrophysics Data System (ADS)

    Zhao, Qi; Wen, Hong-yuan; Zhou, Mu-chun; Chen, Yan-ru

    2008-12-01

    There are some problems in Basic Oxygen Furnace (BOF) steelmaking end-point control technology at present. A new BOF end-point control model was designed, which was based on the character of carbon oxygen reaction in Basic Oxygen Furnace steelmaking process. The image capture and transformation system was established by Video for Windows (VFW) library function, which is a video software development package promoted by Microsoft Corporation. In this paper, the Radial Basic Function (RBF) neural network model was established by using the real-time acquisition information. The input parameters can acquire easily online and the output parameter is the end-point time, which can compare with the actual value conveniently. The experience results show that the predication result is ideal and the experiment results show the model can work well in the steelmaking adverse environment.

  15. Springfield Processing Plant* (A Hypothetical Facility) SPP, Entry Control Point and Vehicle Gate Access Control Post Order

    SciTech Connect

    Baum, Gregory A.

    2014-06-01

    This hypothetical order provides the requirements and instructions for the Springfield Processing Plant (SPP) Vehicle Gate and Entry Control Point (ECP) in the perimeter access building. The purpose of this post is to prevent the theft, sabotage or diversion of nuclear material (NM), control access and exit at the protected area, and to respond to emergencies according the SPP Guard Force (GF) Contingency Plan and as directed by a Guard Force Supervisor.

  16. Acute alcohol consumption impairs controlled but not automatic processes in a psychophysical pointing paradigm.

    PubMed

    Johnston, Kevin; Timney, Brian; Goodale, Melvyn A

    2013-01-01

    Numerous studies have investigated the effects of alcohol consumption on controlled and automatic cognitive processes. Such studies have shown that alcohol impairs performance on tasks requiring conscious, intentional control, while leaving automatic performance relatively intact. Here, we sought to extend these findings to aspects of visuomotor control by investigating the effects of alcohol in a visuomotor pointing paradigm that allowed us to separate the influence of controlled and automatic processes. Six male participants were assigned to an experimental "correction" condition in which they were instructed to point at a visual target as quickly and accurately as possible. On a small percentage of trials, the target "jumped" to a new location. On these trials, the participants' task was to amend their movement such that they pointed to the new target location. A second group of 6 participants were assigned to a "countermanding" condition, in which they were instructed to terminate their movements upon detection of target "jumps". In both the correction and countermanding conditions, participants served as their own controls, taking part in alcohol and no-alcohol conditions on separate days. Alcohol had no effect on participants' ability to correct movements "in flight", but impaired the ability to withhold such automatic corrections. Our data support the notion that alcohol selectively impairs controlled processes in the visuomotor domain.

  17. Public Data Set: Control and Automation of the Pegasus Multi-point Thomson Scattering System

    SciTech Connect

    Bodner, Grant M.; Bongard, Michael W.; Fonck, Raymond J.; Reusch, Joshua A.; Rodriguez Sanchez, Cuauhtemoc; Schlossberg, David J.

    2016-08-12

    This public data set contains openly-documented, machine readable digital research data corresponding to figures published in G.M. Bodner et al., 'Control and Automation of the Pegasus Multi-point Thomson Scattering System,' Rev. Sci. Instrum. 87, 11E523 (2016).

  18. State feedback control of surge oscillations of two-point mooring system

    NASA Astrophysics Data System (ADS)

    Mitra, R. K.; Banik, A. K.; Chatterjee, S.

    2017-01-01

    Stability analysis of surge oscillations of two-point mooring system under state feedback control with time-delay is investigated. The two-point mooring system is harmonically excited and essentially represents a strongly nonlinear Duffing oscillator. In this paper, a frequency domain based method viz. incremental harmonic balance method along with arc-length continuation technique (IHBC) is first employed to identify the primary and higher order subharmonic responses which may be present in such system. The IHBC is then reformulated in a manner to treat two-point mooring system under state feedback control with time-delay and is applied to obtain control of responses in an efficient and systematic way. The stability of uncontrolled responses for primary and higher order subharmonic oscillations is obtained by Floquet's theory using Hsu' scheme; whereas the stability of controlled responses is obtained by applying semi-discretization method for delay differential equation. The study focussed on the controlling primary, higher order subharmonics and chaotic responses by considering appropriate feedback gains and delay by way of (i) appreciable reduction of primary, subharmonic responses, (ii) exclusion of all higher order subharmonics 2T, 3T, 5T and 9T (1/n subharmonics or period-n solutions), and (iii) reduction of the extent of domain of all instability phenomena represented by various type of bifurcation of solutions, jump phenomena, chaotic responses etc. In the study, negative velocity feedback is observed to be much effective than state feedback for better controlling of surge oscillation of two-point mooring system. Also, the effect of larger gain values is investigated by an extensive parametric study for vibration control with different delay values.

  19. Loop Heat Pipe Operation Using Heat Source Temperature for Set Point Control

    NASA Technical Reports Server (NTRS)

    Ku, Jentung; Paiva, Kleber; Mantelli, Marcia

    2011-01-01

    Loop heat pipes (LHPs) have been used for thermal control of several NASA and commercial orbiting spacecraft. The LHP operating temperature is governed by the saturation temperature of its compensation chamber (CC). Most LHPs use the CC temperature for feedback control of its operating temperature. There exists a thermal resistance between the heat source to be cooled by the LHP and the LHP's CC. Even if the CC set point temperature is controlled precisely, the heat source temperature will still vary with its heat output. For most applications, controlling the heat source temperature is of most interest. A logical question to ask is: "Can the heat source temperature be used for feedback control of the LHP operation?" A test program has been implemented to answer the above question. Objective is to investigate the LHP performance using the CC temperature and the heat source temperature for feedback control

  20. Application of Model Reference Adaptive Control System to Instrument Pointing System /IPS/

    NASA Technical Reports Server (NTRS)

    Waites, H. B.

    1979-01-01

    A Model Reference Adaptive Controller (MRAC) is derived for a Shuttle payload called the Instrument Pointing System (IPS). The unique features of this MRAC design are that total state feedback is not required, that the internal structure of the model is independent of the internal structure of the IPS, and that the model input is of bounded variation and not required a priori. An application of Liapunov's stability theorems is used to synthesize a control signal which assures MRAC asymptotic stability. Exponential observers are used to obtain the necessary state information to implement the control synthesis. Results are presented which show how effectively the MRAC can maneuver the IPS.

  1. Center manifold analysis of a point vortex model of vortex shedding with control

    NASA Astrophysics Data System (ADS)

    Protas, Bartosz

    2007-04-01

    In this paper we use methods of dynamical systems theory to provide a precise mathematical characterization of the behavior of the point vortex Föppl system with a linear feedback control. The Föppl system was used in an earlier investigation as a simple model for control design for vortex shedding and numerical studies indicated that the state of the controlled system converges to a closed orbit. In this investigation we prove rigorously that this observed behavior in fact represents periodic oscillations on the center manifold of the closed-loop nonlinear system. This manifold is shown to coincide with the uncontrollable subspace of the linearized system.

  2. Human factors aspects of the major upgrade to the control systems at the LANL plutonium facility

    SciTech Connect

    Higgins, J.C.; Pope, N.

    1997-04-01

    The Plutonium Facility (TA-55) at Los Alamos National Laboratory (LANL) has been in operation for almost 20 years. The Operations Center of TA-55 is the nerve center of the facility where operators are on duty around the clock and monitor several thousand data points using the Facility Control System (FCS). The FCS monitors, displays, alarms, and provides some limited control of several systems, including: HVAC, fire detection and suppression, radiation detection, and electrical. The FCS was failing and needed to be replaced expeditiously. This paper will discuss the human factors aspects of the design, installation, and testing of the new FCS within the above noted constraints. Particular items to be discussed include the functional requirements definition, operating experience review, screen designs, test program, operator training, and phased activation of the new circuits in an operational facility.

  3. Immune response genes controlling responsiveness to major transplantation antigens. Specific major histocompatibility complex-linked defect for antibody responses to class I alloantigens

    SciTech Connect

    Butcher, G.W.; Corvalan, J.R.; Licence, D.R.; Howard, J.C.

    1982-01-01

    We have identified two major histocompatibility complex (MHC)-linked Ir genes that control the antibody response made by rats against class I major alloantigens. We have named these genes Ir-RT1Aa and Ir-RT1Ac. These Ir genes determine responsiveness of the immunized animal in a typical codominant fashion. There is no evidence so far for trans-complementation between low-responder haplotypes. Detailed studies of Ir-RT1Aa indicate that it controls the antibody response to at least two distinct alloantigenic determinants on RT1Aa molecules. These class I molecules thus behave like hapten-carrier conjugates when the response against the carrier is under Ir gene control. Analysis of the origin of alloantibody-forming cells in tetraparental radiation chimeras indicates that Ir-RT1Aa must control the provision of effective help to B cells. In many respects therefore, the properties of Ir-RT1Aa are broadly similar to those described for Ir genes controlling antibody responses to conventional antigens. The existence of apparently conventional Ir genes controlling the antibody response to major alloantigens strongly suggest that the processing of these transmembrane molecules by host antigen-presenting cells is a prerequisite for immune induction, and that it is the MHC of the responder rather than that of the allograft to which T helper cells are restricted in alloimmune responses in vivo.

  4. Stimulus control and generalization of point-loss punishment with humans.

    PubMed Central

    O'Donnell, J; Crosbie, J; Williams, D C; Saunders, K J

    2000-01-01

    Two experiments demonstrated stimulus control and generalization of conditioned punishment with humans. In both studies, responses first were reinforced with points exchangeable for money on a variable-interval schedule in the presence of one line length (S(D)). Next, a second line length was introduced, and point loss followed every response in the presence of that line (S(D)p). In the final training condition, points were deducted at session end. Response rate was lower in the presence of the S(D)p despite equal rates of points for money in the presence of both stimuli. In generalization testing for Experiment 1, the two lines were included in a 10-line continuum; S(D)p fell in the middle and the trained SD was at one end. Lines were presented randomly, and point delivery and loss contingencies were as in training but with points available in the presence of all lines. For all subjects, response rates were lowest around S(D)p and increased towards the SD end of the continuum. Because testing included only one or two lines beyond S(D), this pattern did not rule out S(D) generalization. Thus, in Experiment 2, stimuli beyond S(D) were added to generalization tests. Response rates did not decrease as a function of distance from S(D), clarifying the demonstration of punishment generalization. PMID:10866351

  5. SIM Lite Guide-2 telescope system identification, control design and pointing performance evaluation

    NASA Astrophysics Data System (ADS)

    Shields, Joel F.; Boussalis, Dhemetrio; Fathpour, Nanaz; Weilert, Mark; Hahn, Inseob; Ahmed, Asif

    2010-07-01

    The Guide-2 telescope (G2T) is an important subsystem of the new SIM Lite Astrometric Observatory. In this paper we present system identification experiments, design and implementation of the G2T stellar pointing loop that achieves milliarcsecond resolution of spacecraft attitude. Special emphasis was placed on characterization and modeling of PZT hysteresis since this nonlinearity plays an important part in the control loop performance. Power spectral densities of the star image centroids were use to evaluate the pointing loop performance with and with out the presence of simulated ACS disturbances injected via a fast steering mirror (FSM).

  6. Habit control during growth on GaN point seed crystals by Na-flux method

    NASA Astrophysics Data System (ADS)

    Honjo, Masatomo; Imanishi, Masayuki; Imabayashi, Hiroki; Nakamura, Kosuke; Murakami, Kosuke; Matsuo, Daisuke; Maruyama, Mihoko; Imade, Mamoru; Yoshimura, Masashi; Mori, Yusuke

    2017-01-01

    The formation of the pyramidal habit is one of the requirements for the dramatic reduction of dislocations during growth on a tiny GaN seed called a “point seed”. In this study, we focus on controlling the growth habit to form a pyramidal shape in order to reduce the number of dislocations in the c-growth sector during growth on GaN point seeds. High temperature growth was found to change the growth habit from the truncated pyramidal shape to the pyramidal shape. As a result, the number of dislocations in the c-growth sector tended to decrease with increasing growth temperature.

  7. Using Fast-Steering Mirror Control to Reduce Instrument Pointing Errors Caused by Spacecraft Jitter

    NASA Technical Reports Server (NTRS)

    Antol, Jeffery; Holtz, Ted M.; Cuda, Vince; Johnson, Thomas A.

    1996-01-01

    The scope of this study was to investigate the benefit of using feedback control of a Fast Steering Mirror (FSM) to reduce instrument pointing errors. Initially, the study identified FSM control technologies and categorized them according to their use, range of applicability, and physical requirements. Candidate payloads were then evaluated according to their relevance in use of fast steering minor control technologies. This leads to the mission and instrument selection which served as the candidate mission for numerical modeling. A standard SmallSat was designed in order to accommodate the payload requirements (weight, size, power, etc.). This included sizing the SmallSat bus, sizing the solar array, choosing appropriate antennas, and identifying an attitude control system (ACS). A feedback control system for the FSM compensation was then designed, and the instrument pointing error and SmallSat jitter environment for open-loop and closed-loop FSM control were evaluated for typical SmallSat disturbances. The results were then compared to determine the effectiveness of the FSM feedback control system.

  8. A Globally Stable Lyapunov Pointing and Rate Controller for the Magnetospheric MultiScale Mission (MMS)

    NASA Technical Reports Server (NTRS)

    Shah, Neerav

    2011-01-01

    The Magnetospheric MultiScale Mission (MMS) is scheduled to launch in late 2014. Its primary goal is to discover the fundamental plasma physics processes of reconnection in the Earth's magnetosphere. Each of the four MMS spacecraft is spin-stabilized at a nominal rate of 3 RPM. Traditional spin-stabilized spacecraft have used a number of separate modes to control nutation, spin rate, and precession. To reduce the number of modes and simplify operations, the Delta-H control mode is designed to accomplish nutation control, spin rate control, and precession control simultaneously. A nonlinear design technique, Lyapunov's method, is used to design the Delta-H control mode. A global spin rate controller selected as the baseline controller for MMS, proved to be insufficient due to an ambiguity in the attitude. Lyapunov's design method was used to solve this ambiguity, resulting in a controller that meets the design goals. Simulation results show the advantage of the pointing and rate controller for maneuvers larger than 90 deg and provide insight into the performance of this controller.

  9. Subliminal psychodynamic activation: an experiment controlling for major possible confounding influences outlined by Fudin.

    PubMed

    Gustafson, R; Källmén, H

    1991-08-01

    40 and 48 subjects participated in two separate experiments aimed at reproducing the subliminal psychodynamic activation (SPA) phenomenon and taking into account the major methodological critique by Fudin (1986, 1990). Subjects were first exposed either to a full or one of all possible partial symbiotic messages and then to their anagram equivalents. Confounding and irrelevant influences were controlled; the results indicate that only the full symbiotic message improved motor performance. This strongly suggests that subjects encode the meaning of the full message and supports an interpretation in terms of an alleviation of an internal symbiotic conflict leading to a state of calmness conducive to improved motor performance.

  10. PointCom: semi-autonomous UGV control with intuitive interface

    NASA Astrophysics Data System (ADS)

    Rohde, Mitchell M.; Perlin, Victor E.; Iagnemma, Karl D.; Lupa, Robert M.; Rohde, Steven M.; Overholt, James; Fiorani, Graham

    2008-04-01

    Unmanned ground vehicles (UGVs) will play an important role in the nation's next-generation ground force. Advances in sensing, control, and computing have enabled a new generation of technologies that bridge the gap between manual UGV teleoperation and full autonomy. In this paper, we present current research on a unique command and control system for UGVs named PointCom (Point-and-Go Command). PointCom is a semi-autonomous command system for one or multiple UGVs. The system, when complete, will be easy to operate and will enable significant reduction in operator workload by utilizing an intuitive image-based control framework for UGV navigation and allowing a single operator to command multiple UGVs. The project leverages new image processing algorithms for monocular visual servoing and odometry to yield a unique, high-performance fused navigation system. Human Computer Interface (HCI) techniques from the entertainment software industry are being used to develop video-game style interfaces that require little training and build upon the navigation capabilities. By combining an advanced navigation system with an intuitive interface, a semi-autonomous control and navigation system is being created that is robust, user friendly, and less burdensome than many current generation systems. mand).

  11. Geometric Calibration of ZIYUAN-3 Three-Line Cameras Combining Ground Control Points and Lines

    NASA Astrophysics Data System (ADS)

    Cao, Jinshan; Yuan, Xiuxiao; Gong, Jianya

    2016-06-01

    Due to the large biases between the laboratory-calibrated values of the orientation parameters and their in-orbit true values, the initial direct georeferencing accuracy of the Ziyuan-3 (ZY-3) three-line camera (TLC) images can only reach the kilometre level. In this paper, a point-based geometric calibration model of the ZY-3 TLCs is firstly established by using the collinearity constraint, and then a line-based geometric calibration model is established by using the coplanarity constraint. With the help of both the point-based and the line-based models, a feasible in-orbit geometric calibration approach for the ZY-3 TLCs combining ground control points (GCPs) and ground control lines (GCLs) is presented. Experimental results show that like GCPs, GCLs can also provide effective ground control information for the geometric calibration of the ZY-3 TLCs. The calibration accuracy of the look angles of charge-coupled device (CCD) detectors achieved by using the presented approach reached up to about 1.0''. After the geometric calibration, the direct georeferencing accuracy of the ZY-3 TLC images without ground controls was significantly improved from the kilometre level to better than 11 m in planimetry and 9 m in height. A more satisfactory georeferencing accuracy of better than 3.5 m in planimetry and 3.0 m in height was achieved after the block adjustment with four GCPs.

  12. Initial experiments on the end-point control of a flexible one-link robot

    NASA Technical Reports Server (NTRS)

    Cannon, R. H., Jr.; Schmitz, E.

    1984-01-01

    The present investigation is concerned with initial experiments regarding a specific unsolved control problem which appeared to be central to advances in the art of robotics. This problem involves the control of a flexible member (one link of a robot system). The position of the end-effector, called the end point or tip, is controlled by measuring that position and using the measurement as a basis for applying control torque to the other end of the flexible member, as for instance, the robot's elbow joint. A description is presented of the features of the first experimental arm which has been made, and an outline is provided of the general strategy for controlling it using its tip sensor and shoulder torquer.

  13. Assessment of hygiene standards and Hazard Analysis Critical Control Points implementation on passenger ships.

    PubMed

    Mouchtouri, Varavara; Malissiova, Eleni; Zisis, Panagiotis; Paparizou, Evina; Hadjichristodoulou, Christos

    2013-01-01

    The level of hygiene on ferries can have impact on travellers' health. The aim of this study was to assess the hygiene standards of ferries in Greece and to investigate whether Hazard Analysis Critical Control Points (HACCP) implementation contributes to the hygiene status and particularly food safety aboard passenger ships. Hygiene inspections on 17 ferries in Greece were performed using a standardized inspection form, with a 135-point scale. Thirty-four water and 17 food samples were collected and analysed. About 65% (11/17) of ferries were scored with >100 points. Ferries with HACCP received higher scores during inspection compared to those without HACCP (p value <0.001). All 34 microbiological water test results were found negative and, from the 17 food samples, only one was found positive for Salmonella spp. Implementation of management systems including HACCP principles can help to raise the level of hygiene aboard passenger ships.

  14. Low-boiling-point solvent additives can also enable morphological control in polymer solar cells

    SciTech Connect

    Mahadevapuram, Rakesh C.; Carr, John A.; Chen, Yuqing; Bose, Sayantan; Nalwa, Kanwar S.; Petrich, Jacob W.; Chaudhary, Sumit

    2013-11-02

    Processing organic photovoltaic (OPV) blend solutions with high-boiling-point solvent additives has recently been used for morphological control in bulk-heterojunction OPV cells. Here we show that even low-boiling-point solvents can be effective additives. When P3HT:PCBM OPV cells were processed with a low-boiling-point solvent tetrahydrafuran as an additive in parent solvent o-dichlorobenzene, charge extraction increased leading to fill factors as high as 69.5%, without low work-function cathodes, electrode buffer layers or thermal treatment. This was attributed to PCBM demixing from P3HT domains and better vertical phase separation, as indicated by photoluminescence lifetimes, hole mobilities, and shunt leakage currents. Dependence on solvent parameters and applicability beyond P3HT system was also investigated. (C) 2013 Elsevier B.V. All rights reserved.

  15. Loop Heat Pipe Operation Using Heat Source Temperature for Set Point Control

    NASA Technical Reports Server (NTRS)

    Ku, Jentung; Paiva, Kleber; Mantelli, Marcia

    2011-01-01

    The LHP operating temperature is governed by the saturation temperature of its reservoir. Controlling the reservoir saturation temperature is commonly accomplished by cold biasing the reservoir and using electrical heaters to provide the required control power. Using this method, the loop operating temperature can be controlled within +/- 0.5K. However, because of the thermal resistance that exists between the heat source and the LHP evaporator, the heat source temperature will vary with its heat output even if LHP operating temperature is kept constant. Since maintaining a constant heat source temperature is of most interest, a question often raised is whether the heat source temperature can be used for LHP set point temperature control. A test program with a miniature LHP has been carried out to investigate the effects on the LHP operation when the control temperature sensor is placed on the heat source instead of the reservoir. In these tests, the LHP reservoir is cold-biased and is heated by a control heater. Tests results show that it is feasible to use the heat source temperature for feedback control of the LHP operation. Using this method, the heat source temperature can be maintained within a tight range for moderate and high powers. At low powers, however, temperature oscillations may occur due to interactions among the reservoir control heater power, the heat source mass, and the heat output from the heat source. In addition, the heat source temperature could temporarily deviate from its set point during fast thermal transients. The implication is that more sophisticated feedback control algorithms need to be implemented for LHP transient operation when the heat source temperature is used for feedback control.

  16. Design of set-point weighting PIλ + Dμ controller for vertical magnetic flux controller in Damavand tokamak.

    PubMed

    Rasouli, H; Fatehi, A

    2014-12-01

    In this paper, a simple method is presented for tuning weighted PI(λ) + D(μ) controller parameters based on the pole placement controller of pseudo-second-order fractional systems. One of the advantages of this controller is capability of reducing the disturbance effects and improving response to input, simultaneously. In the following sections, the performance of this controller is evaluated experimentally to control the vertical magnetic flux in Damavand tokamak. For this work, at first a fractional order model is identified using output-error technique in time domain. For various practical experiments, having desired time responses for magnetic flux in Damavand tokamak, is vital. To approach this, at first the desired closed loop reference models are obtained based on generalized characteristic ratio assignment method in fractional order systems. After that, for the identified model, a set-point weighting PI(λ) + D(μ) controller is designed and simulated. Finally, this controller is implemented on digital signal processor control system of the plant to fast/slow control of magnetic flux. The practical results show appropriate performance of this controller.

  17. Treating major depression with yoga: A prospective, randomized, controlled pilot trial

    PubMed Central

    Rivera, Renee; Cochran, Ashly; Tungol, Jose Gabriel; Fayazmanesh, Nima; Weinmann, Eva

    2017-01-01

    Background Conventional pharmacotherapies and psychotherapies for major depression are associated with limited adherence to care and relatively low remission rates. Yoga may offer an alternative treatment option, but rigorous studies are few. This randomized controlled trial with blinded outcome assessors examined an 8-week hatha yoga intervention as mono-therapy for mild-to-moderate major depression. Methods Investigators recruited 38 adults in San Francisco meeting criteria for major depression of mild-to-moderate severity, per structured psychiatric interview and scores of 14–28 on Beck Depression Inventory-II (BDI). At screening, individuals engaged in psychotherapy, antidepressant pharmacotherapy, herbal or nutraceutical mood therapies, or mind-body practices were excluded. Participants were 68% female, with mean age 43.4 years (SD = 14.8, range = 22–72), and mean BDI score 22.4 (SD = 4.5). Twenty participants were randomized to 90-minute hatha yoga practice groups twice weekly for 8 weeks. Eighteen participants were randomized to 90-minute attention control education groups twice weekly for 8 weeks. Certified yoga instructors delivered both interventions at a university clinic. Primary outcome was depression severity, measured by BDI scores every 2 weeks from baseline to 8 weeks. Secondary outcomes were self-efficacy and self-esteem, measured by scores on the General Self-Efficacy Scale (GSES) and Rosenberg Self-Esteem Scale (RSES) at baseline and at 8 weeks. Results In intent-to-treat analysis, yoga participants exhibited significantly greater 8-week decline in BDI scores than controls (p-value = 0.034). In sub-analyses of participants completing final 8-week measures, yoga participants were more likely to achieve remission, defined per final BDI score ≤ 9 (p-value = 0.018). Effect size of yoga in reducing BDI scores was large, per Cohen’s d = -0.96 [95%CI, -1.81 to -0.12]. Intervention groups did not differ significantly in 8-week change scores for

  18. Bounded trajectories near collinear-like equilibrium points of elongated asteroids using linear control

    NASA Astrophysics Data System (ADS)

    Yang, Hongwei; Baoyin, Hexi; Bai, Xiaoli; Li, Jingyang

    2017-02-01

    A new method of obtaining bounded trajectories near collinear-like equilibrium points of elongated asteroids using a simple linear control is proposed. The characteristic equation of the linearized equation of motion near the collinear-like equilibrium points is reduced based on the property of the second derivatives of the effective potential. According to the reduced characteristic equation, the motion is decoupled into an in-plane motion and a out-of-plane motion. The solutions to the decoupled equation of motion are derived and the corresponding Lissajous trajectories are chosen as desired trajectories. A simple linear control, which tracks the Lissajous trajectories, is formulated with the stability conditions of gains. The effectiveness of the proposed method is validated by simulations using high fidelity models of 216 Kleopatra and 951 Gaspra.

  19. Akara Ogbomoso: microbiological examination and identification of hazards and critical control points.

    PubMed

    Lateef, A; Davies, T E; Adelekan, A; Adelere, I A; Adedeji, A A; Fadahunsi, A H

    2010-10-01

    Akara Ogbomoso was examined toward the establishment of hazard analysis and critical control point (HACCP). The akara was produced in residential buildings with the attendant consequence of contamination. There was ample growth of aerobes, coliforms, staphylococci, Shigella and yeast/mold from the samples, water and cowpea pastes. Microbial contaminations occur through the processing, which can be corrected through education by adopting good hygienic and manufacturing practices. The critical control points were identified as frying, storage and refrying. It may be heated in the microwave for 10 s before consumption. Akara, prepared in the laboratory through the implementation of HACCP was not contaminated. Several bacterial isolates, namely; Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, Citrobacter freundii, Serratia marcescens, Proteus vulgaris, Bacillus cereus, Streptococcus pyogenes, Bacillus sp. and Shigella sp., showed multiple resistance to antibiotics ranging from two to nine. Seven strains were not resistant to the antibiotics, while five were resistant to one type of antibiotic.

  20. Hazard analysis and critical control point systems in the United States Department of Agriculture regulatory policy.

    PubMed

    Billy, T J; Wachsmuth, I K

    1997-08-01

    Recent outbreaks of foodborne illness and studies by expert groups have established the need for fundamental change in the United States meat and poultry inspection programme to reduce the risk of foodborne illness. The Food Safety and Inspection Service (FSIS) of the United States Department of Agriculture (USDA) has embarked on a broad effort to bring about such change, with particular emphasis on the reduction of pathogenic micro-organisms in raw meat and poultry products. The publication on 25 July 1996 of the Final Rule on pathogen reduction and hazard analysis and critical control point (HACCP) systems was a major milestone in the FSIS strategy for change. The Final Rule provides a framework for change and clarifies the respective roles of industry and government in ensuring the safety of meat and poultry products. With the implementation of this Final Rule underway, the FSIS has been exploring ways in which slaughter inspection carried out under an HACCP-based system can be changed so that food safety risks are addressed more adequately and the allocation of inspection resources is improved further. In addition, the FSIS is broadening the focus of food safety activities to extend beyond slaughter and processing plants by working with industry, academia and other government agencies. Such co-operation should lead to the development of measures to improve food safety before animals reach the slaughter plant and after products leave the inspected establishment for distribution to the retail level. For the future, the FSIS believes that quantitative risk assessments will be at the core of food safety activities. Risk assessments provide the most effective means of identifying how specific pathogens and other hazards may be encountered throughout the farm-to-table chain and of measuring the potential impact of various interventions. In addition, these assessments will be used in the development and evaluation of HACCP systems. The FSIS is currently conducting a

  1. 40 CFR 63.1583 - What are the emission points and control requirements for an industrial POTW treatment plant?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....1583 What are the emission points and control requirements for an industrial POTW treatment plant? (a) The emission points and control requirements for an existing industrial POTW treatment plant are... control requirements for an industrial POTW treatment plant? 63.1583 Section 63.1583 Protection...

  2. Chaos control in a chaotic system with only one stable equilibrium point

    NASA Astrophysics Data System (ADS)

    Buscarino, Arturo; Fortuna, Luigi; Frasca, Mattia; Gambuzza, Lucia Valentina; Pham, Thanh Viet

    2012-09-01

    The recent finding on the effect of a small bias in Sprott-like systems, i.e., the stabilization of the unstable equilibrium point through the addition of a small bias [1], paves the way to efficient methods for chaos control in such systems. In this work, we investigate the control of one of such systems both in the ideal case of absence of noise and in the presence of noise. We then propose an experimental setup for the experimental verification of the introduced method.

  3. Eigensensitivity in integrated design. [of earth-pointing satellite's control system

    NASA Technical Reports Server (NTRS)

    Kenny, Sean P.; Hou, Gene J.; Belvin, W. K.

    1990-01-01

    An application of eigensensitivity analysis to the control-structure integrated design process is presented with an emphasis placed on computational efficiency improvement of the overall design optimization process. The computational efficiency of eigenvalue/vector sensitivity analysis is demonstrated using the Earth Pointing Satellite in the context of a control-structure integrated design program. Results for a 2 percent design variable perturbation with and without the effects of the actuator mass show a 42 and 52 percent reduction in CPU time, respectively.

  4. Synergies in the space of control variables within the equilibrium-point hypothesis

    PubMed Central

    Ambike, Satyajit; Mattos, Daniela; Zatsiorsky, Vladimir M.; Latash, Mark L.

    2015-01-01

    We use an approach rooted in the recent theory of synergies to analyze possible co-variation between two hypothetical control variables involved in finger force production based in the equilibrium-point hypothesis. These control variables are the referent coordinate (R) and apparent stiffness (C) of the finger. We tested a hypothesis that inter-trial co-variation in the {R; C} space during repeated, accurate force production trials stabilizes the fingertip force. This was expected to correspond to a relatively low amount of inter-trial variability affecting force and a high amount of variability keeping the force unchanged. We used the “inverse piano” apparatus to apply small and smooth positional perturbations to fingers during force production tasks. Across trials, R and C showed strong co-variation with the data points lying close to a hyperbolic curve. Hyperbolic regressions accounted for over 99% of the variance in the {R; C} space. Another analysis was conducted by randomizing the original {R; C} data sets and creating surrogate data sets that were then used to compute predicted force values. The surrogate sets always showed much higher force variance compared to the actual data, thus reinforcing the conclusion that finger force control was organized in the {R; C} space, as predicted by the equilibrium-point hypothesis, and involved co-variation in that space stabilizing total force. PMID:26701299

  5. Critical control points of complementary food preparation and handling in eastern Nigeria.

    PubMed Central

    Ehiri, J. E.; Azubuike, M. C.; Ubbaonu, C. N.; Anyanwu, E. C.; Ibe, K. M.; Ogbonna, M. O.

    2001-01-01

    OBJECTIVE: To investigate microbial contamination and critical control points (CCPs) in the preparation and handling of complementary foods in 120 households in Imo state, Nigeria. METHODS: The Hazard Analysis Critical Control Point (HACCP) approach was used to investigate processes and procedures that contributed to microbial contamination, growth and survival, and to identify points where controls could be applied to prevent or eliminate these microbiological hazards or reduce them to acceptable levels. Food samples were collected and tested microbiologically at different stages of preparation and handling. FINDINGS: During cooking, all foods attained temperatures capable of destroying vegetative forms of food-borne pathogens. However, the risk of contamination increased by storage of food at ambient temperature, by using insufficiently high temperatures to reheat the food, and by adding contaminated ingredients such as dried ground crayfish and soybean powder at stages where no further heat treatment was applied. The purchasing of contaminated raw foodstuffs and ingredients, particularly raw akamu, from vendors in open markets is also a CCP. CONCLUSION: Although an unsafe environment poses many hazards for children's food, the hygienic quality of prepared food can be assured if basic food safety principles are observed. When many factors contribute to food contamination, identification of CCPs becomes particularly important and can facilitate appropriate targeting of resources and prevention efforts. PMID:11417038

  6. Feedback controlled electromigration for the fabrication of point contacts and noise measurement applications

    NASA Astrophysics Data System (ADS)

    Campbell, Jennifer Maureen

    Lithographically fabricated point contacts serve as important examples of mesoscopic conductors, as electrodes for molecular electronics, and as ultra-sensitive transducers for mechanical motion. We have developed a reproducible technique for fabricating metallic point contacts through electromigration. We employ fast analog feedback in a four-wire configuration in combination with slower computer controlled feedback to avoid catastrophic instability even when there is significant series resistance. This hybrid system allows electromigration to proceed while dissipating approximately constant power in the wire. We are able to control the final resistance of the point contact precisely below 5 kO and to within a factor of three when the target resistance approaches 12 kO where only a single conducting channel remains. This system makes it possible to efficiently create point contacts through electromigration for fundamental studies of atomic-size conductors or applications such as displacement transducers. As an application of the hybrid feedback system for forming point contacts, we have developed a low-temperature, high-frequency noise measurement system. The system, which operates from 0.8 to 1.5 GHz at temperatures as low as 320 mK, takes advantage of impedance matching techniques to improve power transfer by up to 65%. This is accomplished by combining an inductor with unavoidable stray capacitance to form a resonant LC circuit. Noise measurement tests with a photodiode-LED pair at room temperature demonstrated the ability to resolve shot noise down to 5 x 10--26 A 2/Hz. This corresponds to the shot noise of 155 nA through a single channel point contact. We designed and fabricated an aluminum superconducting planar inductor coupled to a gold point contact wire to test the noise measurement system at ultra-low temperatures. Finite element simulations suggested that the inductor may not be superconducting at the onset of electromigration but the study was not

  7. Optimal control of a spinning double-pyramid Earth-pointing tethered formation

    NASA Astrophysics Data System (ADS)

    Williams, Paul

    2009-06-01

    The dynamics and control of a tethered satellite formation for Earth-pointing observation missions is considered. For most practical applications in Earth orbit, a tether formation must be spinning in order to maintain tension in the tethers. It is possible to obtain periodic spinning solutions for a triangular formation whose initial conditions are close to the orbit normal. However, these solutions contain significant deviations of the satellites on a sphere relative to the desired Earth-pointing configuration. To maintain a plane of satellites spinning normal to the orbit plane, it is necessary to utilize "anchors". Such a configuration resembles a double-pyramid. In this paper, control of a double-pyramid tethered formation is studied. The equations of motion are derived in a floating orbital coordinate system for the general case of an elliptic reference orbit. The motion of the satellites is derived assuming inelastic tethers that can vary in length in a controlled manner. Cartesian coordinates in a rotating reference frame attached to the desired spin frame provide a simple means of expressing the equations of motion, together with a set of constraint equations for the tether tensions. Periodic optimal control theory is applied to the system to determine sets of controlled periodic trajectories by varying the lengths of all interconnecting tethers (nine in total), as well as retrieval and simple reconfiguration trajectories. A modal analysis of the system is also performed using a lumped mass representation of the tethers.

  8. Development of safe mechanism for surgical robots using equilibrium point control method.

    PubMed

    Park, Shinsuk; Lim, Hokjin; Kim, Byeong-sang; Song, Jae-bok

    2006-01-01

    This paper introduces a novel mechanism for surgical robotic systems to generate human arm-like compliant motion. The mechanism is based on the idea of the equilibrium point control hypothesis which claims that multi-joint limb movements are achieved by shifting the limbs' equilibrium positions defined by neuromuscular activity. The equilibrium point control can be implemented on a robot manipulator by installing two actuators at each joint of the manipulator, one to control the joint position, and the other to control the joint stiffness. This double-actuator mechanism allows us to arbitrarily manipulate the stiffness (or impedance) of a robotic manipulator as well as its position. Also, the force at the end-effector can be estimated based on joint stiffness and joint angle changes without using force transducers. A two-link manipulator and a three-link manipulator with the double-actuator units have been developed, and experiments and simulation results show the potential of the proposed approach. By creating the human arm-like behavior, this mechanism can improve the performance of robot manipulators to execute stable and safe movement in surgical environments by using a simple control scheme.

  9. Dithering Digital Ripple Correlation Control for Photovoltaic Maximum Power Point Tracking

    SciTech Connect

    Barth, C; Pilawa-Podgurski, RCN

    2015-08-01

    This study demonstrates a new method for rapid and precise maximum power point tracking in photovoltaic (PV) applications using dithered PWM control. Constraints imposed by efficiency, cost, and component size limit the available PWM resolution of a power converter, and may in turn limit the MPP tracking efficiency of the PV system. In these scenarios, PWM dithering can be used to improve average PWM resolution. In this study, we present a control technique that uses ripple correlation control (RCC) on the dithering ripple, thereby achieving simultaneous fast tracking speed and high tracking accuracy. Moreover, the proposed method solves some of the practical challenges that have to date limited the effectiveness of RCC in solar PV applications. We present a theoretical derivation of the principles behind dithering digital ripple correlation control, as well as experimental results that show excellent tracking speed and accuracy with basic hardware requirements.

  10. [Zoning planning in non-point source pollution control in Hanyang district].

    PubMed

    Yang, Liu; Ma, Ke-Ming; Guo, Qing-Hai; Zhao, Jing-Zhu; Luo, Yong-Feng

    2006-01-01

    It is most important for managing urban non-point source (NPS) pollution, actualizing the urban sustainable development as well, that zoning planning of urban NPS pollution control is studied. A case study on principles and methods of zoning planning in urban NPS pollution is carried out. Principles of urban sustainable development, priority of urban NPS pollution sensitivity, similarity of urban NPS control direction and region conjugate are put forward. Besides, it is for the first time that a more quantitive method is presented, in the case of Hanyang district, Wuhan city, which is based on L-THIA model and spatial analysis technique in GIS. Assessment of NPS pollution status quo, as well as analysis of NPS sensitivity, is the kernel component of the quantitive method. Hanyang might be divided into four NPS pollution control zones. It is helpful for decision-making of regional NPS pollution control.

  11. Testing of an End-Point Control Unit Designed to Enable Precision Control of Manipulator-Coupled Spacecraft

    NASA Technical Reports Server (NTRS)

    Montgomery, Raymond C.; Ghosh, Dave; Tobbe, Patrick A.; Weathers, John M.; Manouchehri, Davoud; Lindsay, Thomas S.

    1994-01-01

    This paper presents an end-point control concept designed to enable precision telerobotic control of manipulator-coupled spacecraft. The concept employs a hardware unit (end-point control unit EPCU) that is positioned between the end-effector of the Space Shuttle Remote Manipulator System and the payload. Features of the unit are active compliance (control of the displacement between the end-effector and the payload), to allow precision control of payload motions, and inertial load relief, to prevent the transmission of loads between the end-effector and the payload. This paper presents the concept and studies the active compliance feature using a simulation and hardware. Results of the simulation show the effectiveness of the EPCU in smoothing the motion of the payload. Results are presented from initial, limited tests of a laboratory hardware unit on a robotic arm testbed at the l Space Flight Center. Tracking performance of the arm in a constant speed automated retraction and extension maneuver of a heavy payload with and without the unit active is compared for the design speed and higher speeds. Simultaneous load reduction and tracking performance are demonstrated using the EPCU.

  12. Polluted dust derived from long-range transport as a major end member of urban aerosols and its implication of non-point pollution in northern China.

    PubMed

    Yan, Y; Sun, Y B; Weiss, D; Liang, L J; Chen, H Y

    2015-02-15

    The contribution of polluted dust transported from local and distal sources remains poorly constrained due to their similar geophysical and geochemical properties. We sampled aerosols in three cities in northern China (Xi'an, Beijing, Xifeng) during the spring of 2009 to determine dust flux, magnetic susceptibility and elemental concentrations. Combining dust fluxes with wind speed and regional visibility records enabled to differentiate between dust transported from long range and derived from local sources, while the combination of magnetic susceptibility and enrichment factors (EF) of heavy metals (Pb, Zn) allowed to distinguish natural aerosols from polluted ones. Our results indicate that polluted dust from long-range transport became a major end member of urban dust aerosols. Human settlements as its potential sources were confirmed by a pollutant enriched regional dust event originating from populated areas to the south as inferred by back trajectory modeling, implying their non-point source nature of dust pollution.

  13. Neuromodulation of Attentional Control in Major Depression: A Pilot DeepTMS Study

    PubMed Central

    Naim-Feil, Jodie; Bradshaw, John L.; Sheppard, Dianne M.; Rosenberg, Oded; Levkovitz, Yechiel; Fitzgerald, Paul B.; Isserles, Moshe; Zangen, Abraham

    2016-01-01

    While Major Depressive Disorder (MDD) is primarily characterized by mood disturbances, impaired attentional control is increasingly identified as a critical feature of depression. Deep transcranial magnetic stimulation (deepTMS), a noninvasive neuromodulatory technique, can modulate neural activity and induce neuroplasticity changes in brain regions recruited by attentional processes. This study examined whether acute and long-term high-frequency repetitive deepTMS to the dorsolateral prefrontal cortex (DLPFC) can attenuate attentional deficits associated with MDD. Twenty-one MDD patients and 26 matched control subjects (CS) were administered the Beck Depression Inventory and the Sustained Attention to Response Task (SART) at baseline. MDD patients were readministered the SART and depressive assessments following a single session (n = 21) and after 4 weeks (n = 13) of high-frequency (20 Hz) repetitive deepTMS applied to the DLPFC. To control for the practice effect, CS (n = 26) were readministered the SART a further two times. The MDD group exhibited deficits in sustained attention and cognitive inhibition. Both acute and long-term high-frequency repetitive frontal deepTMS ameliorated sustained attention deficits in the MDD group. Improvement after acute deepTMS was related to attentional recovery after long-term deepTMS. Longer-term improvement in sustained attention was not related to antidepressant effects of deepTMS treatment. PMID:26823985

  14. Research on automatic optimization of ground control points in image geometric rectification based on Voronoi diagram

    NASA Astrophysics Data System (ADS)

    Li, Ying; Cheng, Bo

    2009-10-01

    With the development of remote sensing satellites, the data quantity of remote sensing image is increasing tremendously, which brings a huge workload to the image geometric rectification through manual ground control point (GCP) selections. GCP database is one of the effective methods to cut down manual operation. The GCP loaded from database is generally redundant, which may result in a rectification slowdown. How to automatically optimize these ground control points is a problem that should be resolved urgently. According to the basic theory of geometric rectification and the principle of GCP selection, this paper deeply comprehends some existing methods about automatic optimization of GCP, and puts forward a new method of automatic optimization of GCP based on voronoi diagram to filter ground control points from the overfull ones without manual subjectivity for better accuracy. The paper is organized as follows: First, it clarifies the basic theory of remote sensing image multinomial geometric rectification and the arithmetic of how to get the GCP error. Second, it particularly introduces the voronoi diagram including its origin, development and characteristics, especially the creating process. Third, considering the deficiencies of existing methods about automatic optimization of GCP, the paper presents the idea of applying voronoi diagram to filter GCP in order to complete automatic optimization. During this process, it advances the conception of single GCP's importance value based on voronoi diagram. Then by integrating the GCP error and GCP's importance value, the paper gives the theory and the flow of automatic optimization of GCPs as well. It also presents an example of the application of this method. In the conclusion, it points out the advantages of automatic optimization of GCP based on the voronoi diagram.

  15. Interpersonal psychotherapy (IPT) for major depression following perinatal loss: a pilot randomized controlled trial.

    PubMed

    Johnson, Jennifer E; Price, Ann Back; Kao, Jennifer Chienwen; Fernandes, Karen; Stout, Robert; Gobin, Robyn L; Zlotnick, Caron

    2016-10-01

    This randomized controlled pilot trial examined the feasibility, acceptability, and preliminary efficacy of an adapted interpersonal psychotherapy (IPT) for major depressive disorder (MDD) following perinatal loss (miscarriage, stillbirth, or early neonatal death). Fifty women who experienced a perinatal loss within the past 18 months, whose current depressive episode onset occurred during or after the loss, were randomized to the group IPT adapted for perinatal loss (the Group IPT for Major Depression Following Perinatal Loss manual developed for this study is available at no cost by contacting either of the first two authors) or to the group Coping with Depression (CWD), a cognitive behavioral treatment which did not focus on perinatal loss nor social support. Assessments occurred at baseline, treatment weeks 4 and 8, post-treatment, and 3 and 6 months after the end of treatment. IPT was feasible and acceptable in this population. Although some participants were initially hesitant to discuss their losses in a group (as occurred in IPT but not CWD), end of treatment satisfaction scores were significantly (p = 0.001) higher in IPT than in CWD. Confidence intervals around between-groups effect sizes favored IPT for reductions in depressive symptoms during treatment as well as for improvement in mode-specific targets (social support, grief symptoms) and recovery from a post-traumatic stress disorder over follow-up. This group IPT treatment adapted for MDD after perinatal loss is feasible, acceptable, and possibly efficacious.

  16. Identification of a major QTL controlling the content of B-type starch granules in Aegilops

    PubMed Central

    Howard, Thomas; Rejab, Nur Ardiyana; Griffiths, Simon; Leigh, Fiona; Leverington-Waite, Michelle; Simmonds, James; Uauy, Cristobal; Trafford, Kay

    2011-01-01

    Starch within the endosperm of most species of the Triticeae has a unique bimodal granule morphology comprising large lenticular A-type granules and smaller near-spherical B-type granules. However, a few wild wheat species (Aegilops) are known to lack B-granules. Ae. peregrina and a synthetic tetraploid Aegilops with the same genome composition (SU) were found to differ in B-granule number. The synthetic tetraploid had normal A- and B-type starch granules whilst Ae. peregrina had only A-granules because the B-granules failed to initiate. A population segregating for B-granule number was generated by crossing these two accessions and was used to study the genetic basis of B-granule initiation. A combination of Bulked Segregant Analysis and QTL mapping identified a major QTL located on the short arm of chromosome 4S that accounted for 44.4% of the phenotypic variation. The lack of B-granules in polyploid Aegilops with diverse genomes suggests that the B-granule locus has been lost several times independently during the evolution of the Triticeae. It is proposed that the B-granule locus is susceptible to silencing during polyploidization and a model is presented to explain the observed data based on the assumption that the initiation of B-granules is controlled by a single major locus per haploid genome. PMID:21227932

  17. Major QTLs Control Resistance to Rice Hoja Blanca Virus and Its Vector Tagosodes orizicolus

    PubMed Central

    Romero, Luz E.; Lozano, Ivan; Garavito, Andrea; Carabali, Silvio J.; Triana, Monica; Villareal, Natalia; Reyes, Luis; Duque, Myriam C.; Martinez, César P.; Calvert, Lee; Lorieux, Mathias

    2013-01-01

    Rice hoja blanca (white leaf) disease can cause severe yield losses in rice in the Americas. The disease is caused by the rice hoja blanca virus (RHBV), which is transmitted by the planthopper vector Tagosodes orizicolus. Because classical breeding schemes for this disease rely on expensive, time-consuming screenings, there is a need for alternatives such as marker-aided selection. The varieties Fedearroz 2000 and Fedearroz 50, which are resistant to RHBV and to the feeding damage caused by T. orizicolus, were crossed with the susceptible line WC366 to produce segregating F2:3 populations. The F3 families were scored for their resistance level to RHBV and T. orizicolus. The F2:3 lines of both crosses were genotyped using microsatellite markers. One major QTL on the short arm of chromosome 4 was identified for resistance to RHBV in the two populations. Two major QTL on chromosomes 5 and 7 were identified for resistance to T. orizicolus in the Fd2000 × WC366 and Fd50 × WC366 crosses, respectively. This comparative study using two distinct rice populations allowed for a better understanding of how the resistance to RHBV and its vector are controlled genetically. Simple marker-aided breeding schemes based on QTL information can be designed to improve rice germplasm to reduce losses caused by this important disease. PMID:24240781

  18. Hygienic-dietary recommendations for major depression treatment: Study protocol of a randomized controlled trial

    PubMed Central

    2012-01-01

    Background Depression is a highly prevalent and disabling mental disorder with an incidence rate which appears to be increasing in the developed world. This fact seems to be at least partially related to lifestyle factors. Some hygienic-dietary measures have shown their efficacy as a coadjuvant of standard treatment. However, their effectiveness has not yet been proved enough in usual clinical practice. Methods Multicenter, randomized, controlled, two arm-parallel, clinical trial involving 300 patients over 18 years old with a diagnosis of Major Depression. Major depression will be diagnosed by means of the Mini-International Neuropsychiatric Interview. The Beck Depression Inventory total score at the end of the study will constitute the main efficacy outcome. Quality of Life and Social and Health Care Services Consumption Scales will be also administered. Patients will be assessed at three different occasions: baseline, 6-month follow-up and 12-month follow-up. Discussion We expect the patients in the active lifestyle recommendations group to experience a greater improvement in their depressive symptoms and quality of life with lower socio-sanitary costs. Trial registration ISRCTN73931675 PMID:23158080

  19. Major QTLs control resistance to rice hoja blanca virus and its vector Tagosodes orizicolus.

    PubMed

    Romero, Luz E; Lozano, Ivan; Garavito, Andrea; Carabali, Silvio J; Triana, Monica; Villareal, Natalia; Reyes, Luis; Duque, Myriam C; Martinez, César P; Calvert, Lee; Lorieux, Mathias

    2014-01-10

    Rice hoja blanca (white leaf) disease can cause severe yield losses in rice in the Americas. The disease is caused by the rice hoja blanca virus (RHBV), which is transmitted by the planthopper vector Tagosodes orizicolus. Because classical breeding schemes for this disease rely on expensive, time-consuming screenings, there is a need for alternatives such as marker-aided selection. The varieties Fedearroz 2000 and Fedearroz 50, which are resistant to RHBV and to the feeding damage caused by T. orizicolus, were crossed with the susceptible line WC366 to produce segregating F2:3 populations. The F3 families were scored for their resistance level to RHBV and T. orizicolus. The F2:3 lines of both crosses were genotyped using microsatellite markers. One major QTL on the short arm of chromosome 4 was identified for resistance to RHBV in the two populations. Two major QTL on chromosomes 5 and 7 were identified for resistance to T. orizicolus in the Fd2000 × WC366 and Fd50 × WC366 crosses, respectively. This comparative study using two distinct rice populations allowed for a better understanding of how the resistance to RHBV and its vector are controlled genetically. Simple marker-aided breeding schemes based on QTL information can be designed to improve rice germplasm to reduce losses caused by this important disease.

  20. Two-axis Beam Steering Mirror Control system for Precision Pointing and Tracking Applications

    SciTech Connect

    Ulander, Klaus

    2006-01-01

    Precision pointing and tracking of laser beams is critical in numerous military and industrial applications. This is particularly true for systems requiring atmospheric beam propagation. Such systems are plagued by environmental influences which cause the optical signal to break up and wander. Example applications include laser communications, precision targeting, active imaging, chemical remote sensing, and laser vibrometry. The goal of this project is to build a beam steering system using a two-axis mirror to maintain precise pointing control. Ultimately, position control to 0.08% accuracy (40 {micro}rad) with a bandwidth of 200 Hz is desired. The work described encompasses evaluation of the instrumentation system and the subsequent design and implementation of an analog electronic controller for a two-axis mirror used to steer the beam. The controller operates over a wide temperature range, through multiple mirror resonances, and is independent of specific mirrors. The design was built and successfully fielded in a Lawrence Livermore National Laboratory free-space optics experiment. All measurements and performance parameters are derived from measurements made on actual hardware that was built and field tested. In some cases, specific design details have been omitted that involve proprietary information pertaining to Lawrence Livermore National Laboratory patent positions and claims. These omissions in no way impact the general validity of the work or concepts presented in this thesis.

  1. Screening for the synthetic cannabinoid JWH-018 and its major metabolites in human doping controls.

    PubMed

    Möller, Ines; Wintermeyer, Annette; Bender, Katja; Jübner, Martin; Thomas, Andreas; Krug, Oliver; Schänzer, Wilhelm; Thevis, Mario

    2011-09-01

    Referred to as 'spice', several new drugs, advertised as herbal blends, have appeared on the market in the last few years, in which the synthetic cannabinoids JWH-018 and a C(8) homologue of CP 47,497 were identified as major active ingredients. Due to their reported cannabis-like effects, many European countries have banned these substances. The World Anti-Doping Agency has also explicitly prohibited synthetic cannabinoids in elite sport in-competition. Since urine specimens have been the preferred doping control samples, the elucidation of the metabolic pathways of these substances is of particular importance to implement them in sports drug testing programmes. In a recent report, an in vitro phase-I metabolism study of JWH-018 was presented yielding mainly hydroxylated and N-dealkylated metabolites. Due to these findings, a urine sample of a healthy man declaring to have smoked a 'spice' product was screened for potential phase-I and -II metabolites by high-resolution/high-accuracy mass spectrometry in the present report. The majority of the phase-I metabolites observed in earlier in vitro studies of JWH-018 were detected in this urine specimen and furthermore most of their respective monoglucuronides. As no intact JWH-018 was detectable, the monohydroxylated metabolite being the most abundant one was chosen as a target analyte for sports drug testing purposes; a detection method was subsequently developed and validated in accordance to conventional screening protocols based on enzymatic hydrolysis, liquid-liquid extraction, and liquid chromatography/electrospray tandem mass spectrometry analysis. The method was applied to approximately 7500 urine doping control samples yielding two JWH-018 findings and demonstrated its capability for a sensitive and selective identification of JWH-018 and its metabolites in human urine.

  2. The dynamics and control of large flexible space structures, 2. Part A: Shape and orientation control using point actuators

    NASA Technical Reports Server (NTRS)

    Bainum, P. M.; Reddy, A. S. S. R.

    1979-01-01

    The equations of planar motion for a flexible beam in orbit which includes the effects of gravity gradient torques and control torques from point actuators located along the beam was developed. Two classes of theorems are applied to the linearized form of these equations to establish necessary conditions for controlability for preselected actuator configurations. The feedback gains are selected: (1) based on the decoupling of the original coordinates and to obtain proper damping, and (2) by applying the linear regulator problem to the individual model coordinates separately. The linear control laws obtained using both techniques were evaluated by numerical integration of the nonlinear system equations. Numerical examples considering pitch and various number of modes with different combination of actuator numbers and locations are presented. The independent model control concept used earlier with a discretized model of the thin beam in orbit was reviewed for the case where the number of actuators is less than the number of modes. Results indicate that although the system is controllable it is not stable about the nominal (local vertical) orientation when the control is based on modal decoupling. An alternate control law not based on modal decoupling ensures stability of all the modes.

  3. Formation Flying Satellite Control Around the L2 Sun-Earth Libration Point

    NASA Technical Reports Server (NTRS)

    Hamilton, Nicholas H.; Folta, David; Carpenter, Russell; Bauer, Frank (Technical Monitor)

    2002-01-01

    This paper discusses the development of a linear control algorithm for formations in the vicinity of the L2 sun-Earth libration point. The development of a simplified extended Kalman filter is included as well. Simulations are created for the analysis of the stationkeeping and various formation maneuvers of the Stellar Imager mission. The simulations provide tracking error, estimation error, and control effort results. For formation maneuvering, the formation spacecraft track to within 4 meters of their desired position and within 1.5 millimeters per second of their desired zero velocity. The filter, with few exceptions, keeps the estimation errors within their three-sigma values. Without noise, the controller performs extremely well, with the formation spacecraft tracking to within several micrometers. Each spacecraft uses around 1 to 2 grams of propellant per maneuver, depending on the circumstances.

  4. Ground-based telescope pointing and tracking optimization using a neural controller.

    PubMed

    Mancini, D; Brescia, M; Schipani, P

    2003-01-01

    Neural network models (NN) have emerged as important components for applications of adaptive control theories. Their basic generalization capability, based on acquired knowledge, together with execution rapidity and correlation ability between input stimula, are basic attributes to consider NN as an extremely powerful tool for on-line control of complex systems. By a control system point of view, not only accuracy and speed, but also, in some cases, a high level of adaptation capability is required in order to match all working phases of the whole system during its lifetime. This is particularly remarkable for a new generation ground-based telescope control system. Infact, strong changes in terms of system speed and instantaneous position error tolerance are necessary, especially in case of trajectory disturb induced by wind shake. The classical control scheme adopted in such a system is based on the proportional integral (PI) filter, already applied and implemented on a large amount of new generation telescopes, considered as a standard in this technological environment. In this paper we introduce the concept of a new approach, the neural variable structure proportional integral, (NVSPI), related to the implementation of a standard multi layer perceptron network in new generation ground-based Alt-Az telescope control systems. Its main purpose is to improve adaptive capability of the Variable structure proportional integral model, an already innovative control scheme recently introduced by authors [Proc SPIE (1997)], based on a modified version of classical PI control model, in terms of flexibility and accuracy of the dynamic response range also in presence of wind noise effects. The realization of a powerful well tested and validated telescope model simulation system allowed the possibility to directly compare performances of the two control schemes on simulated tracking trajectories, revealing extremely encouraging results in terms of NVSPI control robustness and

  5. Pathogen Reduction and Hazard Analysis and Critical Control Point (HACCP) systems for meat and poultry. USDA.

    PubMed

    Hogue, A T; White, P L; Heminover, J A

    1998-03-01

    The United States Department of Agriculture (USDA) Food Safety Inspection Service (FSIS) adopted Hazard Analysis and Critical Control Point Systems and established finished product standards for Salmonella in slaughter plants to improve food safety for meat and poultry. In order to make significant improvements in food safety, measures must be taken at all points in the farm-to-table chain including production, transportation, slaughter, processing, storage, retail, and food preparation. Since pathogens can be introduced or multiplied anywhere along the continuum, success depends on consideration and comparison of intervention measures throughout the continuum. Food animal and public health veterinarians can create the necessary preventative environment that mitigates risks for food borne pathogen contamination.

  6. Point source modeling of matched case-control data with multiple disease subtypes.

    PubMed

    Li, Shi; Mukherjee, Bhramar; Batterman, Stuart

    2012-12-10

    In this paper, we propose nonlinear distance-odds models investigating elevated odds around point sources of exposure, under a matched case-control design where there are subtypes within cases. We consider models analogous to the polychotomous logit models and adjacent-category logit models for categorical outcomes and extend them to the nonlinear distance-odds context. We consider multiple point sources as well as covariate adjustments. We evaluate maximum likelihood, profile likelihood, iteratively reweighted least squares, and a hierarchical Bayesian approach using Markov chain Monte Carlo techniques under these distance-odds models. We compare these methods using an extensive simulation study and show that with multiple parameters and a nonlinear model, Bayesian methods have advantages in terms of estimation stability, precision, and interpretation. We illustrate the methods by analyzing Medicaid claims data corresponding to the pediatric asthma population in Detroit, Michigan, from 2004 to 2006.

  7. The Hazard Analysis and Critical Control Points (HACCP) generic model for the production of Thai fermented pork sausage (Nham).

    PubMed

    Paukatong, K V; Kunawasen, S

    2001-01-01

    Nham is a traditional Thai fermented pork sausage. The major ingredients of Nham are ground pork meat and shredded pork rind. Nham has been reported to be contaminated with Salmonella spp., Staphylococcus aureus, and Listeria monocytogenes. Therefore, it is a potential cause of foodborne diseases for consumers. A Hazard Analysis and Critical Control Points (HACCP) generic model has been developed for the Nham process. Nham processing plants were observed and a generic flow diagram of Nham processes was constructed. Hazard analysis was then conducted. Other than microbial hazards, the pathogens previously found in Nham, sodium nitrite and metal were identified as chemical and physical hazards in this product, respectively. Four steps in the Nham process have been identified as critical control points. These steps are the weighing of the nitrite compound, stuffing, fermentation, and labeling. The chemical hazard of nitrite must be controlled during the weighing step. The critical limit of nitrite levels in the Nham mixture has been set at 100-200 ppm. This level is high enough to control Clostridium botulinum but does not cause chemical hazards to the consumer. The physical hazard from metal clips could be prevented by visual inspection of every Nham product during stuffing. The microbiological hazard in Nham could be reduced in the fermentation process. The critical limit of the pH of Nham was set at lower than 4.6. Since this product is not cooked during processing, finally, educating the consumer, by providing information on the label such as "safe if cooked before consumption", could be an alternative way to prevent the microbiological hazards of this product.

  8. Control of sediment concentration in major rivers of the Nepal Himalayas

    NASA Astrophysics Data System (ADS)

    Crave, A.; Andermann, C.; Gloaguen, R.; Bonnet, S.

    2010-12-01

    Sediment concentration in river systems of active mountain belts is key indicators to estimate present-day erosion rates. Erosion in the Himalayas is mainly controlled by the annual recurrence and intensity of the Indian summer monsoon system. But nevertheless short lasting events can be responsible for more than the half of the material transported. Temporal variability in concentration is attributed by changes of discharge and hence access to different supply sources as well as alteration of mobilization properties. Controlling factors are precipitation rates and intensities, vegetation cover, duration and limit of annual snow cover as well as seismic events. Today remotely sensed area-wide measurements are available to relate single observable events, such as extreme suspended sediment concentration peaks to their eventual sources. Due to the distinct seasonality, Himalayan rivers experience a distinct annual hydrographe which is highly repetitive. These annual flood cycles cause seasonal hysteresis loops in suspended concentration engraved by short events. Here we present a study on several major rivers in the Nepal Himalayas analyzing there discharge - sediment concentration relationship and its relation with upstream controlling properties, detected by remote sensing. Due to political unsteadiness and difficult accessible terrain, river gauging stations are rare and data not always available. Our station data covers nearly all major rivers, spanning a rainfall gradient from East to West along the Himalayan front. The average annual increase of discharge during monsoon is 1 to two magnitudes with respect to winter baseflow. Considerable Suspended concentrations (100 - 1000 g/l) are observable only within the monsoon season. Short lasting events however can catapult concentration for few short periods above 103 g/l. The occurrence of such events is commonly before peak discharge and its frequency varies from year to year. In same cases one or two events account

  9. Rectification control points selection method of triangle mesh in optical pressure measurement of wind-tunnel test.

    PubMed

    Chen, Yong; Chen, Chang

    2014-08-01

    In optical pressure measurement of wind-tunnel test, triangle mesh is usually built to rectify the images that are distorted in geometry. In this paper, a novel method of control points selection of triangle mesh is proposed by combining the artificial points and margin control points. For the problem that in the condition of wind the margin control point is difficult to extract due to model distortion and grey variation, an improved Smallest Univalue Segment Assimilating Nucleus algorithm based on region selection and adaptive threshold is designed. The connection method is employed to verify the availability of points, which avoids that the noisy points are mistakenly regarded as the angular points. The distorted images of aircraft model are rectified and the results are analyzed. Experiments demonstrate that the proposed method greatly improves the rectification effect.

  10. [The different point of view about the sanitary control of importation of psychotropic substances in Brazil].

    PubMed

    Sebastião, Patrícia Cristina Antunes; Lucchese, Geraldo

    2010-11-01

    The purpose of this work is to analyze the process of importation, that is a part of the sanitary control of psychotropic substances, made by Brazilian National Health Surveillance Agency's ports, airports and borders. For this work, psychotropic substances are defined as active pharmaceutical raw materials present in the list B1 of Portaria nº 344/98; which need Anvisa's permission to be imported. For this purpose we used semistructured interviews with key informers and participant observation. The information were collected and systematized through the content analysis, thematic modality. The results show a very complex control which involves an intense bureaucratic process. The main identified critical points of the process were: the information system precariousness; the absence of human resources; deficiency of laboratorial support and infra-structure at customs. Anvisa's web page and the specific law are strong points of the process, but still needing improvements. We understood that despite of the progress made, there are many things to do for giving the country an efficient health control system to the importation of these substances.

  11. Relapse Prevention in Major Depressive Disorder: Mindfulness-Based Cognitive Therapy Versus an Active Control Condition

    PubMed Central

    Shallcross, Amanda J.; Gross, James J.; Visvanathan, Pallavi D.; Kumar, Niketa; Palfrey, Amy; Ford, Brett Q.; Dimidjian, Sona; Shirk, Stephen; Holm-Denoma, Jill; Goode, Kari M.; Cox, Erica; Chaplin, William; Mauss, Iris B.

    2015-01-01

    Objective We evaluated the comparative effectiveness of Mindfulness-based cognitive therapy (MBCT) versus an active control condition (ACC) for depression relapse prevention, depressive symptom reduction, and improvement in life satisfaction. Method Ninety-two participants in remission from Major Depressive Disorder with residual depressive symptoms were randomized to either an 8-week MBCT or a validated ACC that is structurally equivalent to MBCT and controls for non-specific effects (e.g., interaction with a facilitator, perceived social support, treatment outcome expectations). Both interventions were delivered according to their published manuals. Results Intention-to-treat analyses indicated no differences between MBCT and ACC in depression relapse rates or time to relapse over a 60-week follow-up. Both groups experienced significant and equal reductions in depressive symptoms and improvements in life satisfaction. A significant quadratic interaction (group x time) indicated that the pattern of depressive symptom reduction differed between groups. The ACC experienced immediate symptom reduction post-intervention and then a gradual increase over the 60-week follow-up. The MBCT group experienced a gradual linear symptom reduction. The pattern for life satisfaction was identical but only marginally significant. Conclusions MBCT did not differ from an ACC on rates of depression relapse, symptom reduction, or life satisfaction, suggesting that MBCT is no more effective for preventing depression relapse and reducing depressive symptoms than the active components of the ACC. Differences in trajectory of depressive symptom improvement suggest that the intervention-specific skills acquired may be associated with differential rates of therapeutic benefit. This study demonstrates the importance of comparing psychotherapeutic interventions to active control conditions. PMID:26371618

  12. Doping control analysis of trimetazidine and characterization of major metabolites using mass spectrometric approaches.

    PubMed

    Sigmund, Gerd; Koch, Anja; Orlovius, Anne-Katrin; Guddat, Sven; Thomas, Andreas; Schänzer, Wilhelm; Thevis, Mario

    2014-01-01

    Since January 2014, the anti-anginal drug trimetazidine [1-(2,3,4-trimethoxybenzyl)-piperazine] has been classified as prohibited substance by the World Anti-Doping Agency (WADA), necessitating specific and robust detection methods in sports drug testing laboratories. In the present study, the implementation of the intact therapeutic agent into two different initial testing procedures based on gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) is reported, along with the characterization of urinary metabolites by electrospray ionization-high resolution/high accuracy (tandem) mass spectrometry. For GC-MS analyses, urine samples were subjected to liquid-liquid extraction sample preparation, while LC-MS/MS analyses were conducted by established 'dilute-and-inject' approaches. Both screening methods were validated for trimetazidine concerning specificity, limits of detection (0.5-50 ng/mL), intra-day and inter-day imprecision (<20%), and recovery (41%) in case of the GC-MS-based method. In addition, major metabolites such as the desmethylated trimetazidine and the corresponding sulfoconjugate, oxo-trimetazidine, and trimetazidine-N-oxide as identified in doping control samples were used to complement the LC-MS/MS-based assay, although intact trimetazidine was found at highest abundance of the relevant trimetazidine-related analytes in all tested sports drug testing samples. Retrospective data mining regarding doping control analyses conducted between 1999 and 2013 at the Cologne Doping Control Laboratory concerning trimetazidine revealed a considerable prevalence of the drug particularly in endurance and strength sports accounting for up to 39 findings per year.

  13. Datum maintenance of the main Egyptian geodetic control networks by utilizing Precise Point Positioning "PPP" technique

    NASA Astrophysics Data System (ADS)

    Rabah, Mostafa; Elmewafey, Mahmoud; Farahan, Magda H.

    2016-06-01

    A geodetic control network is the wire-frame or the skeleton on which continuous and consistent mapping, Geographic Information Systems (GIS), and surveys are based. Traditionally, geodetic control points are established as permanent physical monuments placed in the ground and precisely marked, located, and documented. With the development of satellite surveying methods and their availability and high degree of accuracy, a geodetic control network could be established by using GNSS and referred to an international terrestrial reference frame used as a three-dimensional geocentric reference system for a country. Based on this concept, in 1992, the Egypt Survey Authority (ESA) established two networks, namely High Accuracy Reference Network (HARN) and the National Agricultural Cadastral Network (NACN). To transfer the International Terrestrial Reference Frame to the HARN, the HARN was connected with four IGS stations. The processing results were 1:10,000,000 (Order A) for HARN and 1:1,000,000 (Order B) for NACN relative network accuracy standard between stations defined in ITRF1994 Epoch1996. Since 1996, ESA did not perform any updating or maintaining works for these networks. To see how non-performing maintenance degrading the values of the HARN and NACN, the available HARN and NACN stations in the Nile Delta were observed. The Processing of the tested part was done by CSRS-PPP Service based on utilizing Precise Point Positioning "PPP" and Trimble Business Center "TBC". The study shows the feasibility of Precise Point Positioning in updating the absolute positioning of the HARN network and its role in updating the reference frame (ITRF). The study also confirmed the necessity of the absent role of datum maintenance of Egypt networks.

  14. Uncertainty Analysis of non-point source pollution control facilities design techniques in Korea

    NASA Astrophysics Data System (ADS)

    Lee, J.; Okjeong, L.; Gyeong, C. B.; Park, M. W.; Kim, S.

    2015-12-01

    The design of non-point sources control facilities in Korea is divided largely by the stormwater capture ratio, the stormwater load capture ratio, and the pollutant reduction efficiency of the facility. The stormwater capture ratio is given by a design formula as a function of the water quality treatment capacity, the greater the capacity, the more the amount of stormwater intercepted by the facility. The stormwater load capture ratio is defined as the ratio of the load entering the facility of the total pollutant load generated in the target catchment, and is given as a design formula represented by a function of the stormwater capture ratio. In order to estimate the stormwater capture ratio and load capture ratio, a lot of quantitative analysis of hydrologic processes acted in pollutant emission is required, but these formulas have been applied without any verification. Since systematic monitoring programs were insufficient, verification of these formulas was fundamentally impossible. However, recently the Korean ministry of Environment has conducted an long-term systematic monitoring project, and thus the verification of the formulas became possible. In this presentation, the stormwater capture ratio and load capture ratio are re-estimated using actual TP data obtained from long-term monitoring program at Noksan industrial complex located in Busan, Korea. Through the re-estimated process, the uncertainty included in the design process that has been applied until now will be shown in a quantitative extent. In addition, each uncertainty included in the stormwater capture ratio estimation and in the stormwater load capture ratio estimation will be expressed to quantify the relative impact on the overall non-point pollutant control facilities design process. Finally, the SWMM-Matlab interlocking module for model parameters estimation will be introduced. Acknowledgement This subject is supported by Korea Ministry of Environment as "The Eco Innovation Project : Non-point

  15. Robust Brain-Machine Interface Design Using Optimal Feedback Control Modeling and Adaptive Point Process Filtering

    PubMed Central

    Carmena, Jose M.

    2016-01-01

    Much progress has been made in brain-machine interfaces (BMI) using decoders such as Kalman filters and finding their parameters with closed-loop decoder adaptation (CLDA). However, current decoders do not model the spikes directly, and hence may limit the processing time-scale of BMI control and adaptation. Moreover, while specialized CLDA techniques for intention estimation and assisted training exist, a unified and systematic CLDA framework that generalizes across different setups is lacking. Here we develop a novel closed-loop BMI training architecture that allows for processing, control, and adaptation using spike events, enables robust control and extends to various tasks. Moreover, we develop a unified control-theoretic CLDA framework within which intention estimation, assisted training, and adaptation are performed. The architecture incorporates an infinite-horizon optimal feedback-control (OFC) model of the brain’s behavior in closed-loop BMI control, and a point process model of spikes. The OFC model infers the user’s motor intention during CLDA—a process termed intention estimation. OFC is also used to design an autonomous and dynamic assisted training technique. The point process model allows for neural processing, control and decoder adaptation with every spike event and at a faster time-scale than current decoders; it also enables dynamic spike-event-based parameter adaptation unlike current CLDA methods that use batch-based adaptation on much slower adaptation time-scales. We conducted closed-loop experiments in a non-human primate over tens of days to dissociate the effects of these novel CLDA components. The OFC intention estimation improved BMI performance compared with current intention estimation techniques. OFC assisted training allowed the subject to consistently achieve proficient control. Spike-event-based adaptation resulted in faster and more consistent performance convergence compared with batch-based methods, and was robust to

  16. Robust Brain-Machine Interface Design Using Optimal Feedback Control Modeling and Adaptive Point Process Filtering.

    PubMed

    Shanechi, Maryam M; Orsborn, Amy L; Carmena, Jose M

    2016-04-01

    Much progress has been made in brain-machine interfaces (BMI) using decoders such as Kalman filters and finding their parameters with closed-loop decoder adaptation (CLDA). However, current decoders do not model the spikes directly, and hence may limit the processing time-scale of BMI control and adaptation. Moreover, while specialized CLDA techniques for intention estimation and assisted training exist, a unified and systematic CLDA framework that generalizes across different setups is lacking. Here we develop a novel closed-loop BMI training architecture that allows for processing, control, and adaptation using spike events, enables robust control and extends to various tasks. Moreover, we develop a unified control-theoretic CLDA framework within which intention estimation, assisted training, and adaptation are performed. The architecture incorporates an infinite-horizon optimal feedback-control (OFC) model of the brain's behavior in closed-loop BMI control, and a point process model of spikes. The OFC model infers the user's motor intention during CLDA-a process termed intention estimation. OFC is also used to design an autonomous and dynamic assisted training technique. The point process model allows for neural processing, control and decoder adaptation with every spike event and at a faster time-scale than current decoders; it also enables dynamic spike-event-based parameter adaptation unlike current CLDA methods that use batch-based adaptation on much slower adaptation time-scales. We conducted closed-loop experiments in a non-human primate over tens of days to dissociate the effects of these novel CLDA components. The OFC intention estimation improved BMI performance compared with current intention estimation techniques. OFC assisted training allowed the subject to consistently achieve proficient control. Spike-event-based adaptation resulted in faster and more consistent performance convergence compared with batch-based methods, and was robust to parameter

  17. The hazard analysis and critical control point system in food safety.

    PubMed

    Herrera, Anavella Gaitan

    2004-01-01

    The Hazard Analysis and Critical Control Point (HACCP) system is a preventive method of ensuring food safety. Its objectives are the identification of consumer safety hazards that can occur in the production line and the establishment of a control process to guarantee a safer product for the consumer; it is based on the identification of potential hazards to food safety and on measures aimed at preventing these hazards. HACCP is the system of choice in the management of food safety. The principles of HACCP are applicable to all phases of food production, including basic husbandry practices, food preparation and handling, food processing, food service, distribution systems, and consumer handling and use. The HACCP system is involved in every aspect of food safety production (according to the UN Food and Agriculture Organization [FAO] and the International Commission on Microbiological Specifications for Foods [ICMSF]). The most basic concept underlying the HACCP system is that of prevention rather than inspection. The control of processes and conditions comprises the critical control point (CCP) element. HACCP is simply a methodical, flexible, and systematic application of the appropriate science and technology for planning, controlling, and documenting the safe production of foods. The successful application of HACCP requires the full commitment and involvement of management and the workforce, using a multidisciplinary approach that should include, as appropriate, expertise in agronomy, veterinary health, microbiology, public health, food technology, environmental health, chemistry, engineering, and so on according to the particular situation. Application of the HACCP system is compatible with the implementation of total quality management (TQM) systems such as the ISO 9000 series.

  18. Stability and control problems in Earth-Moon Lagrangian point L2

    NASA Astrophysics Data System (ADS)

    Palutan, F.

    1994-11-01

    The use of periodic trajectories around L2 Lagrangian point for lunar operations has been proposed by many authors. A single telecommunication relay, place around L2, could guarantee the permanent connection between the Earth and a lunar base on the far side of the moon, with a 440,000 km link from the Earth and a 64,000 km link from the lunar surface. However, the control of a satellite in L2 Lagrangian point is quite difficult, due to the intrinsic dynamic unstability. To do it, it is necessary to observe continuously the orbital state of the satellite, and control the dynamics of the vehicle with a suitable on-board propulsion system. The analysis of these problems was performed by Farquhar, starting from 1970, and others (Sim, et al 1987). The same concepts were developed, by the author, in a study for European Space Agency (ESA) on a space communication network, for lunar and deep space missions. The present communication describes the dynamics in L2 and in the periodic orbits around L2 (halo orbits). It discusses the possibility of the orbit control, with a particular reference to the control laws based on the observation of the position and velocity of the spacecraft in the Earth-Moon direction. Some numerical simulations are presented, performed with a numerical propagator, to verify the dynamics of the satellite in presence of the perturbations, not accounted for in a simplified analytical approach. The possibility of controlling the satellite with a station-keeping procedure, similar to that used for geostationary satellites, is verified.

  19. 41 CFR 101-26.606 - Supply support available from the inventory control points of the military departments.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... from the inventory control points of the military departments. 101-26.606 Section 101-26.606 Public... § 101-26.606 Supply support available from the inventory control points of the military departments. Federal civil agencies may obtain items of supply which are procured and managed by the inventory...

  20. 41 CFR 101-26.606 - Supply support available from the inventory control points of the military departments.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... from the inventory control points of the military departments. 101-26.606 Section 101-26.606 Public... § 101-26.606 Supply support available from the inventory control points of the military departments. Federal civil agencies may obtain items of supply which are procured and managed by the inventory...

  1. Floating-point scaling technique for sources separation automatic gain control

    NASA Astrophysics Data System (ADS)

    Fermas, A.; Belouchrani, A.; Ait-Mohamed, O.

    2012-07-01

    Based on the floating-point representation and taking advantage of scaling factor indetermination in blind source separation (BSS) processing, we propose a scaling technique applied to the separation matrix, to avoid the saturation or the weakness in the recovered source signals. This technique performs an automatic gain control in an on-line BSS environment. We demonstrate the effectiveness of this technique by using the implementation of a division-free BSS algorithm with two inputs, two outputs. The proposed technique is computationally cheaper and efficient for a hardware implementation compared to the Euclidean normalisation.

  2. Evidence for a major gene controlling susceptibility to tegumentary leishmaniasis in a recently exposed Bolivian population.

    PubMed Central

    Alcaïs, A; Abel, L; David, C; Torrez, M E; Flandre, P; Dedet, J P

    1997-01-01

    Tegumentary leishmaniasis due to Leishmania braziliensis is a parasitic disease that occurs in two stages after the infected sandfly bite: (1) a primary cutaneous lesion followed by (2) a secondary mucosal involvement generally resulting in severe facial deformities. In order to investigate the genetic and environmental factors involved in the development of the cutaneous lesion, a familial study was performed in a region of Bolivia in which the disease is endemic. Complete selection of 118 nuclear families (703 subjects, with 241 patients), each with at least one cutaneous affected subject, was achieved; 41 families were of native origin, and 77 (herein designated "migrant") recently had settled in the area. For the analysis, the trait under study was the time to onset of the primary cutaneous lesion. The start of the follow-up was birth, for native population, or date of arrival in the endemic area, for migrant population. Segregation analysis was performed by use of a model based on survival analysis methods that allows joint estimation of genetic and environmental effects and accounts for gene x covariate interactions. A significant effect of gender, home-forest distance, and forest-related activity was found. In the 77 migrant families there was evidence for a recessive major gene controlling the onset of the primary cutaneous lesion, with residual familial dependences and age x genotype interaction. Penetrance estimations show that young subjects are genetically more susceptible than older subjects, suggesting that this genetic component could concern mechanisms involved in the development of individual protection during childhood. There was also a significant genetic heterogeneity of the sample according to the native/migrant origin of the families, and no major-gene effect was found in the native subsample. PMID:9382111

  3. Efficacy and safety of deep transcranial magnetic stimulation for major depression: a prospective multicenter randomized controlled trial

    PubMed Central

    Levkovitz, Yechiel; Isserles, Moshe; Padberg, Frank; Lisanby, Sarah H; Bystritsky, Alexander; Xia, Guohua; Tendler, Aron; Daskalakis, Zafiris J; Winston, Jaron L; Dannon, Pinhas; Hafez, Hisham M; Reti, Irving M; Morales, Oscar G; Schlaepfer, Thomas E; Hollander, Eric; Berman, Joshua A; Husain, Mustafa M; Sofer, Uzi; Stein, Ahava; Adler, Shmulik; Deutsch, Lisa; Deutsch, Frederic; Roth, Yiftach; George, Mark S; Zangen, Abraham

    2015-01-01

    Major depressive disorder (MDD) is a prevalent and disabling condition, and many patients do not respond to available treatments. Deep transcranial magnetic stimulation (dTMS) is a new technology allowing non-surgical stimulation of relatively deep brain areas. This is the first double-blind randomized controlled multicenter study evaluating the efficacy and safety of dTMS in MDD. We recruited 212 MDD outpatients, aged 22–68 years, who had either failed one to four antidepressant trials or not tolerated at least two antidepressant treatments during the current episode. They were randomly assigned to monotherapy with active or sham dTMS. Twenty sessions of dTMS (18 Hz over the prefrontal cortex) were applied during 4 weeks acutely, and then biweekly for 12 weeks. Primary and secondary efficacy endpoints were the change in the Hamilton Depression Rating Scale (HDRS-21) score and response/remission rates at week 5, respectively. dTMS induced a 6.39 point improvement in HDRS-21 scores, while a 3.28 point improvement was observed in the sham group (p+0.008), resulting in a 0.76 effect size. Response and remission rates were higher in the dTMS than in the sham group (response: 38.4 vs. 21.4%, p+0.013; remission: 32.6 vs. 14.6%, p+0.005). These differences between active and sham treatment were stable during the 12-week maintenance phase. dTMS was associated with few and minor side effects apart from one seizure in a patient where a protocol violation occurred. These results suggest that dTMS constitutes a novel intervention in MDD, which is efficacious and safe in patients not responding to antidepressant medications, and whose effect remains stable over 3 months of maintenance treatment. PMID:25655160

  4. Formation Flying Satellite Control Around the L2 Sun-Earth Libration Point

    NASA Astrophysics Data System (ADS)

    Hamilton, Nicholas H.

    2001-12-01

    A growing interest in formation flying satellites demands development and analysis of control and estimation algorithms for station-keeping and formation maneuvering. This thesis discusses the development of a discrete linear-quadratic- regulator control algorithm for formations in the vicinity of the L2 sun-earth libration point. The development of an appropriate Kalman filter is included as well. Simulations are created for the analysis of the station-keeping and various formation maneuvers of the Stellar Imager mission. The simulations provide tracking error, estimation error, and control effort results. From the control effort, useful design parameters such as AV and propellant mass are determined. For formation maneuvering, the drone spacecraft track to within 4 meters of their desired position and within 1.3 millimeters per second of their desired zero velocity. The filter, with few exceptions, keeps the estimation errors within their three-sigma values. Without noise, the controller performs extremely well, with the drones tracking to within several micrometers. Bach drone uses around 1 to 2 grams of propellant per maneuver, depending on the circumstances.

  5. [Major Ionic Features and Their Controlling Factors in the Upper-Middle Reaches of Wujiang River].

    PubMed

    Huang, Qi-bo; Qin, Xiao-qun; Liu, Peng-yu; Lan, Fu-ning; Zhang, Lian-kai; Su, Chun-tian

    2016-05-15

    The Wujing River, the largest river in Guizhou Province, is one of the most important water resources for social and economical development. Recently, with the fast population proliferation and rapid economic growth, the drainage basin is intensively interfered by anthropogenic activities. The hydrochemistry of surface water was analyzed from the upper-middle reaches of Wujiang River for investigating the hydrochemical characteristics and their main influencing factors. The results showed that the major cations of the four rivers were Ca²⁺ and Mg²⁺, accounting for more than 70%, and the main anions were HCO₃⁻ and SO₄²⁻, occupying more than 85%. The hydrochemical characteristics in the four rivers were found to be of HCO₃-Ca type, and mainly determined by the carbonate rock dissolution, while only a small proportion of them were of HCO₃ · SO₄-Ca type, reflecting the influence of SO₄²⁻ from anthropogenic activities. Compared to hydrochemical data in 1999, there was an obvious increase in cations and anions concentrations, majorly in NO₃⁻, SO2- ion concentrations, which were significantly affected by human activities. The Na⁺, K⁺ , Cl⁻ in the river mainly came from atmospheric precipitation, and Ca²⁺, HCO₃⁻, Mg²⁺, mainly came from carbonate rocks dissolution, while NO₃⁻ and SO₄²⁻ mainly came from human activities. According to principal component analysis and correlation analysis, hydrochemical composition of Liuchong River was affected by human activity, and that in the upstream of Sancha River was controlled by atmospheric precipitation and the dissolution of carbonate rocks, that to the downstream was enhanced by human activities. The main ion of Maotiao River was controlled by atmospheric precipitation and carbonate rocks dissolution, and also affected by human activity. The Nanming River, the Qingshui river's tributary, was mainly affected by human activity, while the middle and lower reaches of Qingshui

  6. Pinhole/coronograph pointing control system integration and noise reduction analysis

    NASA Technical Reports Server (NTRS)

    Greene, M.

    1981-01-01

    The Pinhole Occulter Facility (P/OF) is a Space Shuttle based experiment for the production of solar coronographics and hard X-ray images. The system is basically pinhole camera utilizing a deployable 50-m flexible boom for separating the pinholes and coronograph shields from the recording devices located in the Shuttle bay. At the distal end of the boom from the Shuttle is a 25 kg mask containing pinholes and coronograph shields. At the proximal end the detectors are located and mounted, along with the deployable boom, to the ASPS gimbal pointing system (AGS). The mask must be pointed at the Sun with a high degree of pointing stability and accuracy to align the axes of the detectors with the pinholes and shields. Failure to do so will result in a blurring of the images on the detectors and a loss of resolution. Being a Shuttle based experiment, the system will be subjected to the disturbances of the Shuttle. The worst of these is thruster firing for orbit correction; the Shuttle uses a bang-bang thruster control system to maintain orbit to within preset limits. Other disturbances include man motion, motion induced by other systems, and gravity gradient torques.

  7. Interferometric adaptive optics for high power laser pointing, wave-front control and phasing

    SciTech Connect

    Baker, K L; Stappaerts, E A; Homoelle, D C; Henesian, M A; Bliss, E S; Siders, C W; Barty, C J

    2009-01-21

    Implementing the capability to perform fast ignition experiments, as well as, radiography experiments on the National Ignition Facility (NIF) places stringent requirements on the control of each of the beam's pointing and overall wavefront quality. One quad of the NIF beams, 4 beam pairs, will be utilized for these experiments and hydrodynamic and particle-in-cell simulations indicate that for the fast ignition experiments, these beams will be required to deliver 50% (4.0 kJ) of their total energy (7.96 kJ) within a 40 {micro}m diameter spot at the end of a fast ignition cone target. This requirement implies a stringent pointing and overall phase conjugation error budget on the adaptive optics system used to correct these beam lines. The overall encircled energy requirement is more readily met by phasing of the beams in pairs but still requires high Strehl ratios, Sr, and rms tip/tilt errors of approximately one {micro}rad. To accomplish this task we have designed an interferometric adaptive optics system capable of beam pointing, high Strehl ratio and beam phasing with a single pixilated MEMS deformable mirror and interferometric wave-front sensor. We present the design of a testbed used to evaluate the performance of this wave-front sensor below along with simulations of its expected performance level.

  8. Critical Point Facility (CPE) Group in the Spacelab Payload Operations Control Center (SL POCC)

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The primary payload for Space Shuttle Mission STS-42, launched January 22, 1992, was the International Microgravity Laboratory-1 (IML-1), a pressurized manned Spacelab module. The goal of IML-1 was to explore in depth the complex effects of weightlessness of living organisms and materials processing. Around-the-clock research was performed on the human nervous system's adaptation to low gravity and effects of microgravity on other life forms such as shrimp eggs, lentil seedlings, fruit fly eggs, and bacteria. Materials processing experiments were also conducted, including crystal growth from a variety of substances such as enzymes, mercury iodide, and a virus. The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Featured is the Critical Point Facility (CPE) group in the SL POCC during STS-42, IML-1 mission.

  9. Higher order sliding mode control of laser pointing for orbital debris mitigation

    NASA Astrophysics Data System (ADS)

    Palosz, Arthur

    This thesis explores the use of a space-based laser to clean up small orbital debris from near Earth space. This system's challenge is to quickly and precisely aim the laser beam at very small (<1cm) and distant (<10km) moving orbital debris in the presence of parametric uncertainties and external disturbances. A mathematical model is derived for the debris position sensors, a Fast Steering Mirror (FSM), and a telescope which are used to track the orbital debris and then point and focus the laser beam onto the orbital debris. A Kalman Filter (KF) is designed to accurately track the orbital debris and generate a command signal for the controller. A second order Super Twisting Sliding Mode Controller (2-SMC) is designed to follow the command signal generated by the KF and to overcome the parametric uncertainties and external disturbances. The performance of the system is validated with a computer simulation created in MATLAB and Simulink.

  10. Critical Point Facility (CPF) Team in the Spacelab Payload Operations Control Center (SL POCC)

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The primary payload for Space Shuttle Mission STS-42, launched January 22, 1992, was the International Microgravity Laboratory-1 (IML-1), a pressurized manned Spacelab module. The goal of IML-1 was to explore in depth the complex effects of weightlessness of living organisms and materials processing. Around-the-clock research was performed on the human nervous system's adaptation to low gravity and effects of microgravity on other life forms such as shrimp eggs, lentil seedlings, fruit fly eggs, and bacteria. Materials processing experiments were also conducted, including crystal growth from a variety of substances such as enzymes, mercury iodide, and a virus. The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Featured is the Critical Point Facility (CPF) team in the SL POCC during the IML-1 mission.

  11. Adaptive robust maximum power point tracking control for perturbed photovoltaic systems with output voltage estimation.

    PubMed

    Koofigar, Hamid Reza

    2016-01-01

    The problem of maximum power point tracking (MPPT) in photovoltaic (PV) systems, despite the model uncertainties and the variations in environmental circumstances, is addressed. Introducing a mathematical description, an adaptive sliding mode control (ASMC) algorithm is first developed. Unlike many previous investigations, the output voltage is not required to be sensed and the upper bound of system uncertainties and the variations of irradiance and temperature are not required to be known. Estimating the output voltage by an update law, an adaptive-based H∞ tracking algorithm is then developed for the case the perturbations are energy-bounded. The stability analysis is presented for the proposed tracking control schemes, based on the Lyapunov stability theorem. From a comparison viewpoint, some numerical and experimental studies are also presented and discussed.

  12. [The Hazard Analysis Critical Control Point approach (HACCP) in meat production].

    PubMed

    Berends, B R; Snijders, J M

    1994-06-15

    The Hazard Analysis Critical Control Point (HACCP) approach is a method that could transform the current system of safety and quality assurance of meat into a really effective and flexible integrated control system. This article discusses the origin and the basic principles of the HACCP approach. It also discusses why the implementation of the approach is not as widespread as might be expected. It is concluded that a future implementation of the approach in the entire chain of meat production, i.e. from conception to consumption, is possible. Prerequisites are, however, that scientifically validated risk analyses become available, that future legislation forms a framework that actively supports the approach, and that all parties involved in meat production not only become convinced of the advantages, but also are trained to implement the HACCP approach with insight.

  13. Alterations in leukocyte transcriptional control pathway activity associated with major depressive disorder and antidepressant treatment.

    PubMed

    Mellon, S H; Wolkowitz, O M; Schonemann, M D; Epel, E S; Rosser, R; Burke, H B; Mahan, L; Reus, V I; Stamatiou, D; Liew, C-C; Cole, S W

    2016-05-24

    Major depressive disorder (MDD) is associated with a significantly elevated risk of developing serious medical illnesses such as cardiovascular disease, immune impairments, infection, dementia and premature death. Previous work has demonstrated immune dysregulation in subjects with MDD. Using genome-wide transcriptional profiling and promoter-based bioinformatic strategies, we assessed leukocyte transcription factor (TF) activity in leukocytes from 20 unmedicated MDD subjects versus 20 age-, sex- and ethnicity-matched healthy controls, before initiation of antidepressant therapy, and in 17 of the MDD subjects after 8 weeks of sertraline treatment. In leukocytes from unmedicated MDD subjects, bioinformatic analysis of transcription control pathway activity indicated an increased transcriptional activity of cAMP response element-binding/activating TF (CREB/ATF) and increased activity of TFs associated with cellular responses to oxidative stress (nuclear factor erythroid-derived 2-like 2, NFE2l2 or NRF2). Eight weeks of antidepressant therapy was associated with significant reductions in Hamilton Depression Rating Scale scores and reduced activity of NRF2, but not in CREB/ATF activity. Several other transcriptional regulation pathways, including the glucocorticoid receptor (GR), nuclear factor kappa-B cells (NF-κB), early growth response proteins 1-4 (EGR1-4) and interferon-responsive TFs, showed either no significant differences as a function of disease or treatment, or activities that were opposite to those previously hypothesized to be involved in the etiology of MDD or effective treatment. Our results suggest that CREB/ATF and NRF2 signaling may contribute to MDD by activating immune cell transcriptome dynamics that ultimately influence central nervous system (CNS) motivational and affective processes via circulating mediators.

  14. Alterations in leukocyte transcriptional control pathway activity associated with major depressive disorder and antidepressant treatment

    PubMed Central

    Mellon, S H; Wolkowitz, O M; Schonemann, M D; Epel, E S; Rosser, R; Burke, H B; Mahan, L; Reus, V I; Stamatiou, D; Liew, C -C; Cole, S W

    2016-01-01

    Major depressive disorder (MDD) is associated with a significantly elevated risk of developing serious medical illnesses such as cardiovascular disease, immune impairments, infection, dementia and premature death. Previous work has demonstrated immune dysregulation in subjects with MDD. Using genome-wide transcriptional profiling and promoter-based bioinformatic strategies, we assessed leukocyte transcription factor (TF) activity in leukocytes from 20 unmedicated MDD subjects versus 20 age-, sex- and ethnicity-matched healthy controls, before initiation of antidepressant therapy, and in 17 of the MDD subjects after 8 weeks of sertraline treatment. In leukocytes from unmedicated MDD subjects, bioinformatic analysis of transcription control pathway activity indicated an increased transcriptional activity of cAMP response element-binding/activating TF (CREB/ATF) and increased activity of TFs associated with cellular responses to oxidative stress (nuclear factor erythroid-derived 2-like 2, NFE2l2 or NRF2). Eight weeks of antidepressant therapy was associated with significant reductions in Hamilton Depression Rating Scale scores and reduced activity of NRF2, but not in CREB/ATF activity. Several other transcriptional regulation pathways, including the glucocorticoid receptor (GR), nuclear factor kappa-B cells (NF-κB), early growth response proteins 1–4 (EGR1–4) and interferon-responsive TFs, showed either no significant differences as a function of disease or treatment, or activities that were opposite to those previously hypothesized to be involved in the etiology of MDD or effective treatment. Our results suggest that CREB/ATF and NRF2 signaling may contribute to MDD by activating immune cell transcriptome dynamics that ultimately influence central nervous system (CNS) motivational and affective processes via circulating mediators. PMID:27187237

  15. Acupuncture point injection treatment of primary dysmenorrhoea: a randomised, double blind, controlled study

    PubMed Central

    Wade, C; Wang, L; Zhao, W J; Cardini, F; Kronenberg, F; Gui, S Q; Ying, Z; Zhao, N Q; Chao, M T; Yu, J

    2016-01-01

    Objective To determine if injection of vitamin K3 in an acupuncture point is optimal for the treatment of primary dysmenorrhoea, when compared with 2 other injection treatments. Setting A Menstrual Disorder Centre at a public hospital in Shanghai, China. Participants Chinese women aged 14–25 years with severe primary dysmenorrhoea for at least 6 months not relieved by any other treatment were recruited. Exclusion criteria were the use of oral contraceptives, intrauterine devices or anticoagulant drugs, pregnancy, history of abdominal surgery, participation in other therapies for pain and diagnosis of secondary dysmenorrhoea. Eighty patients with primary dysmenorrhoea, as defined on a 4-grade scale, completed the study. Two patients withdrew after randomisation. Interventions A double-blind, double-dummy, randomised controlled trial compared vitamin K3 acupuncture point injection to saline acupuncture point injection and vitamin K3 deep muscle injection. Patients in each group received 3 injections at a single treatment visit. Primary and secondary outcome measures The primary outcome was the difference in subjective perception of pain as measured by an 11 unit Numeric Rating Scale (NRS). Secondary measurements were Cox Pain Intensity and Duration scales and the consumption of analgesic tablets before and after treatment and during 6 following cycles. Results Patients in all 3 groups experienced pain relief from the injection treatments. Differences in NRS measured mean pain scores between the 2 active control groups were less than 1 unit (−0.71, CI −1.37 to −0.05) and not significant, but the differences in average scores between the treatment hypothesised to be optimal and both active control groups (1.11, CI 0.45 to 1.78) and (1.82, CI 1.45 to 2.49) were statistically significant in adjusted mixed-effects models. Menstrual distress and use of analgesics were diminished for 6 months post-treatment. Conclusions Acupuncture point injection of

  16. Realization of tin freezing point using a loop heat pipe-based hydraulic temperature control technique

    NASA Astrophysics Data System (ADS)

    Joung, Wukchul; Gam, Kee Sool; Kim, Yong-Gyoo

    2015-10-01

    In this work, the freezing point of tin (Sn FP) was realized by inside nucleation where the supercooling of tin and the reheating of the sample after the nucleation were achieved without extracting the cell from an isothermal apparatus. To this end, a novel hydraulic temperature control technique, which was based on the thermo-hydraulic characteristics of a pressure-controlled loop heat pipe (LHP), was employed to provide a slow cooling of the sample for deep supercooling and fast reheating after nucleation to minimize the amount of initial freeze of the sample. The required temperature controls were achieved by the active pressure control of a control gas inside the compensation chamber of the pressure-controlled LHP, and slow cooling at  -0.05 K min-1 for the deep supercooling of tin and fast heating at 2 K min-1 for reheating the sample after nucleation was attained. Based on this hydraulic temperature control technique, the nucleation of tin was realized at supercooling of around 19 K, and a satisfactorily fast reheating of the sample to the plateau-producing temperature (i.e. 0.5 K below the Sn FP) was achieved without any temperature overshoots of the isothermal region. The inside-nucleated Sn FP showed many desirable features compared to the Sn FP realized by the conventional outside nucleation method. The longer freezing plateaus and the better immersion characteristics of the Sn FP were obtained by inside nucleation, and the measured freezing temperature of the inside-nucleated Sn FP was as much as 0.37 mK higher than the outside-nucleated Sn FP with an expanded uncertainty of 0.19 mK. Details on the experiment are provided and explanations for the observed differences are discussed.

  17. Research on the modeling of the missile's disturbance motion and the initial control point optimization

    NASA Astrophysics Data System (ADS)

    Guo, Jie; Zhu, Dalin; Tang, Shengjing

    2012-11-01

    The initial trajectory design of the missile is an important part of the overall design, but often a tedious calculation and analysis process due to the large dimension nonlinear differential equations and the traditional statistical analysis methods. To improve the traditional design methods, a robust optimization concept and method are introduced in this paper to deal with the determination of the initial control point. First, the Gaussian Radial Basis Network is adopted to establish the approximate model of the missile's disturbance motion based on the disturbance motion and disturbance factors analysis. Then, a direct analytical relationship between the disturbance input and statistical results is deduced on the basis of Gaussian Radial Basis Network model. Subsequently, a robust optimization model is established aiming at the initial control point design problem and the niche Pareto genetic algorithm for multi-objective optimization is adopted to solve this optimization model. An integral design example is give at last and the simulation results have verified the validity of this method.

  18. Real-time gesture recognition by learning and selective control of visual interest points.

    PubMed

    Kirishima, Toshiyuki; Sato, Kosuke; Chihara, Kunihiro

    2005-03-01

    For the real-time recognition of unspecified gestures by an arbitrary person, a comprehensive framework is presented that addresses two important problems in gesture recognition systems: selective attention and processing frame rate. To address the first problem, we propose the Quadruple Visual Interest Point Strategy. No assumptions are made with regard to scale or rotation of visual features, which are computed from dynamically changing regions of interest in a given image sequence. In this paper, each of the visual features is referred to as a visual interest point, to which a probability density function is assigned, and the selection is carried out. To address the second problem, we developed a selective control method to equip the recognition system with self-load monitoring and controlling functionality. Through evaluation experiments, we show that our approach provides robust recognition with respect to such factors as type of clothing, type of gesture, extent of motion trajectories, and individual differences in motion characteristics. In order to indicate the real-time performance and utility aspects of our approach, a gesture video system is developed that demonstrates full video-rate interaction with displayed image objects.

  19. A novel target LOS calibration method for IR scanning sensor based on control points

    NASA Astrophysics Data System (ADS)

    Xue, Yong-Hong; An, Wei; Zhang, Yin-Sheng; Zhang, Tao

    2012-12-01

    Space based IR system uses the information of target LOS (line of sight) for target location. Recent researches show that the measuring precision of target LOS is usually determined by measuring precision of platform's position and attitude, and deformation of sensor etc. Most methods for improving target location precision are either through improving platform's position and attitude measuring precision or through calib rating the whole image obtained by IR sensor. With the development of measuring technology, it is harder to make a further improvement on the measuring precision of position and attitude of the platform and the expansion of the sensor view make calibrat ion of the whole image with a larger computation cost. In this paper, a method using control points to calibrate target LOS was proposed. Based on the analysis of the imaging process of the scanning sensor of space based IR system, this paper established a modify model of target LOS based on control points, used a bias filter to estimate the bias value of sensor boresight, and finally achieved the mission of target LOS calibrat ion. Different from the traditional calibration method of remote sensing image, the proposed method only made a correct ion on the LOS of suspicious target, but not established the accurate relationship between the all pixels and their real location, and has a similar calibration performance, but more lower computational complexity.

  20. Method for pan-tilt camera calibration using single control point.

    PubMed

    Li, Yunting; Zhang, Jun; Hu, Wenwen; Tian, Jinwen

    2015-01-01

    The pan-tilt (PT) camera is widely used in video surveillance systems due to its rotatable property and low cost. The rough output of a PT camera may not satisfy the demand of practical applications; hence an accurate calibration method of a PT camera is desired. However, high-precision camera calibration methods usually require sufficient control points not guaranteed in some practical cases of a PT camera. In this paper, we present a novel method to online calibrate the rotation angles of a PT camera by using only one control point. This is achieved by assuming that the intrinsic parameters and position of the camera are known in advance. More specifically, we first build a nonlinear PT camera model with respect to two parameters Pan and Tilt. We then convert the nonlinear model into a linear model according to sine and cosine of Tilt, where each element in the augmented coefficient matrix is a function of the single variable Pan. A closed-form solution of Pan and Tilt can then be derived by solving a quadratic equation of tangent of Pan. Our method is noniterative and does not need features matching; thus its time efficiency is better. We evaluate our calibration method on various synthetic and real data. The quantitative results demonstrate that the proposed method outperforms other state-of-the-art methods if the intrinsic parameters and position of the camera are known in advance.

  1. A major gene controls mimicry and crypsis in butterflies and moths

    PubMed Central

    Nadeau, Nicola J.; Pardo-Diaz, Carolina; Whibley, Annabel; Supple, Megan; Saenko, Suzanne V.; Wallbank, Richard W. R.; Wu, Grace C.; Maroja, Luana; Ferguson, Laura; Hanly, Joseph J.; Hines, Heather; Salazar, Camilo; Merrill, Richard; Dowling, Andrea; ffrench-Constant, Richard; Llaurens, Violaine; Joron, Mathieu; McMillan, W. Owen; Jiggins, Chris D.

    2016-01-01

    The wing patterns of butterflies and moths (Lepidoptera) are diverse and striking examples of evolutionary diversification by natural selection1,2. Lepidopteran wing colour patterns are a key innovation, consisting of arrays of coloured scales. We still lack a general understanding of how these patterns are controlled and if there is any commonality across the 160,000 moth and 17,000 butterfly species. Here, we identify a gene, cortex, through fine-scale mapping using population genomics and gene expression analyses, which regulates pattern switches in multiple species across the mimetic radiation in Heliconius butterflies. cortex belongs to a fast evolving subfamily of the otherwise highly conserved fizzy family of cell cycle regulators3, suggesting that it most likely regulates pigmentation patterning through regulation of scale cell development. In parallel with findings in the peppered moth (Biston betularia)4, our results suggest that this mechanism is common within Lepidoptera and that cortex has become a major target for natural selection acting on colour and pattern variation in this group of insects. PMID:27251285

  2. Measuring the distance from saddle points and driving to locate them over quantum control landscapes

    NASA Astrophysics Data System (ADS)

    Sun, Qiuyang; Riviello, Gregory; Wu, Re-Bing; Rabitz, Herschel

    2015-11-01

    Optimal control of quantum phenomena involves the introduction of a cost functional J to characterize the degree of achieving a physical objective by a chosen shaped electromagnetic field. The cost functional dependence upon the control forms a control landscape. Two theoretically important canonical cases are the landscapes associated with seeking to achieve either a physical observable or a unitary transformation. Upon satisfaction of particular assumptions, both landscapes are analytically known to be trap-free, yet possess saddle points at precise suboptimal J values. The presence of saddles on the landscapes can influence the effort needed to find an optimal field. As a foundation to future algorithm development and analyzes, we define metrics that identify the ‘distance’ from a given saddle based on the sufficient and necessary conditions for the existence of the saddles. Algorithms are introduced utilizing the metrics to find a control such that the dynamics arrive at a targeted saddle. The saddle distance metric and saddle-seeking methodology is tested numerically in several model systems.

  3. Neural set point for the control of arterial pressure: role of the nucleus tractus solitarius

    PubMed Central

    2010-01-01

    Background Physiological experiments have shown that the mean arterial blood pressure (MAP) can not be regulated after chemo and cardiopulmonary receptor denervation. Neuro-physiological information suggests that the nucleus tractus solitarius (NTS) is the only structure that receives information from its rostral neural nuclei and from the cardiovascular receptors and projects to nuclei that regulate the circulatory variables. Methods From a control theory perspective, to answer if the cardiovascular regulation has a set point, we should find out whether in the cardiovascular control there is something equivalent to a comparator evaluating the error signal (between the rostral projections to the NTS and the feedback inputs). The NTS would function as a comparator if: a) its lesion suppresses cardiovascular regulation; b) the negative feedback loop still responds normally to perturbations (such as mechanical or electrical) after cutting the rostral afferent fibers to the NTS; c) perturbation of rostral neural structures (RNS) to the NTS modifies the set point without changing the dynamics of the elicited response; and d) cardiovascular responses to perturbations on neural structures within the negative feedback loop compensate for much faster than perturbations on the NTS rostral structures. Results From the control theory framework, experimental evidence found currently in the literature plus experimental results from our group was put together showing that the above-mentioned conditions (to show that the NTS functions as a comparator) are satisfied. Conclusions Physiological experiments suggest that long-term blood pressure is regulated by the nervous system. The NTS functions as a comparator (evaluating the error signal) between its RNS and the cardiovascular receptor afferents and projects to nuclei that regulate the circulatory variables. The mean arterial pressure (MAP) is regulated by the feedback of chemo and cardiopulmonary receptors and the baroreflex

  4. Prevalence, quantification and antimicrobial resistance of Campylobacter spp. on chicken neck-skins at points of slaughter in 5 major cities located on 4 continents.

    PubMed

    Garin, Benoit; Gouali, Malika; Wouafo, Marguerite; Perchec, Anne-Marie; Pham, Minh Thu; Ravaonindrina, Noro; Urbès, Florence; Gay, Manu; Diawara, Abdoulaye; Leclercq, Alexandre; Rocourt, Jocelyne; Pouillot, Régis

    2012-06-15

    Quantitative data on Campylobacter contamination of food are lacking, notably in developing countries. We assessed Campylobacter contamination of chicken neck-skins at points of slaughter in 5 major cities in Africa (Dakar in Senegal, Yaounde in Cameroon), Oceania (Noumea in New Caledonia), the Indian Ocean (Antananarivo in Madagascar) and Asia (Ho Chi Minh City (HCMC) in Vietnam. One hundred and fifty slaughtered chickens were collected in each of the 5 major cities from semi-industrial abattoirs or markets (direct slaughter by the seller), and 65.5% (491/750) were found to be Campylobacter-positive. Two cities, Yaounde and Noumea, demonstrated high prevalence Campylobacter detection rates (92.7% and 96.7% respectively) in contrast with HCMC (15.3%). Four species were identified among 633 isolates, namely C. jejuni (48.3%), C. coli (37.3%), C. lari (11.7%) and C. upsaliensis (1%). HCMC was the only city with C. lari isolation as was Antananarivo for C. upsaliensis. C. coli was highly prevalent only in Yaounde (69.5%). Among the 491 samples positive in Campylobacter detection, 329 were also positive with the enumeration method. The number of Campylobacter colony-forming units (CFU) per gram of neck-skin in samples positive in enumeration was high (mean of the log(10): 3.2 log(10) CFU/g, arithmetic mean: 7900CFU/g). All the cities showed close enumeration means except HCMC with a 1.81 log(10) CFU/g mean for positive samples. Semi-industrial abattoir was linked to a significant lower count of Campylobacter contamination than direct slaughter by the seller (p=0.006). On 546 isolates (546/633, 86.3%) tested for antibiotic susceptibility, resistance to erythromycin, ampicillin and ciprofloxacin was observed for respectively 11%, 19% and 50%. HCMC was the city where antibiotic resistant rates were the highest (95%, p=0.014). Considering the 329 positive chickens in Campylobacter enumeration, the mean number of resistant isolates to at least 2 different antibiotic

  5. Impact of Albumin on Coagulation Competence and Hemorrhage During Major Surgery: A Randomized Controlled Trial.

    PubMed

    Rasmussen, Kirsten C; Højskov, Michael; Johansson, Pär I; Kridina, Irina; Kistorp, Thomas; Salling, Lisbeth; Nielsen, Henning B; Ruhnau, Birgitte; Pedersen, Tom; Secher, Niels H

    2016-03-01

    For patients exposed to a massive blood loss during surgery, maintained coagulation competence is important. It is less obvious whether coagulation competence influences bleeding during elective surgery where patients are exposed to infusion of a crystalloid or a colloid. This randomized controlled trial evaluates whether administration of 5% human albumin (HA) or lactated Ringer solution (LR) affects coagulation competence and in turn blood loss during cystectomy due to bladder cancer. Forty patients undergoing radical cystectomy were included to receive either 5% HA (n = 20) or LR (n = 20). Nineteen patients were analyzed in the HA group and 20 patients in the lactated Ringer group. Blinded determination of the blood loss was similar in the 2 groups of patients: 1658 (800-3300) mL with the use of HA and 1472 (700-4330) mL in the lactated Ringer group (P = 0.45). Yet, by thrombelastography (TEG) evaluated coagulation competence, albumin affected clot growth (TEG-angle 69 ± 5 vs 74° ± 3°, P < 0.01) and strength (TEG-MA: 59 ± 6 vs 67 ± 6 mm, P < 0.001) more than LR. Furthermore, by multivariate linear regression analyses reduced TEG-MA was independently associated with the blood loss (P = 0.042) while administration of albumin was related to the changes in TEG-MA (P = 0.029), aPPT (P < 0.022), and INR (P < 0.033). This randomized controlled trial demonstrates that administration of HA does not affect the blood loss as compared to infusion of LR. Also the use of HA did not affect the need for blood transfusion, the incidence of postoperative complications, or the hospital in-stay. Yet, albumin decreases coagulation competence during major surgery and the blood loss is related to TEG-MA rather than to plasma coagulation variables.

  6. Cloning, Characterization, Controlled Overexpression, and Inactivation of the Major Tributyrin Esterase Gene of Lactococcus lactis

    PubMed Central

    Fernández, Leonides; Beerthuyzen, Marke M.; Brown, Julie; Siezen, Roland J.; Coolbear, Tim; Holland, Ross; Kuipers, Oscar P.

    2000-01-01

    The gene encoding the major intracellular tributyrin esterase of Lactococcus lactis was cloned using degenerate DNA probes based on 19 known N-terminal amino acid residues of the purified enzyme. The gene, named estA, was sequenced and found to encode a protein of 258 amino acid residues. The transcription start site was mapped 233 nucleotides upstream of the start codon, and a canonical promoter sequence was identified. The deduced amino acid sequence of the estA product contained the typical GXSXG motif found in most lipases and esterases. The protein was overproduced up to 170-fold in L. lactis by use of the nisin-controlled expression system recently developed for lactic acid bacteria. The estA gene was inactivated by chromosomal integration of a temperature-sensitive integration vector. This resulted in the complete loss of esterase activity, which could then be recovered after complementation of the constructed esterase-deficient strain with the wild-type estA gene. This confirms that EstA is the main enzyme responsible for esterase activity in L. lactis. Purified recombinant enzyme showed a preference for short-chain acyl esters, surprisingly also including phospholipids. Medium- and long-acyl-chain lipids were also hydrolyzed, albeit less efficiently. Intermediate characteristics between esterases and lipases make intracellular lactococcal EstA difficult to classify in either of these two groups of esterolytic enzymes. We suggest that, in vivo, EstA could be involved in (phospho)lipid metabolism or cellular detoxification or both, as its sequence showed significant similarity to S-formylglutathione hydrolase (FGH) of Paracoccus denitrificans and human EstD (or FGH), which are part of a universal formaldehyde detoxification pathway. PMID:10742212

  7. The value of intermittent point-prevalence surveys of healthcare-associated infections for evaluating infection control interventions at Angkor Hospital for Children, Siem Reap, Cambodia

    PubMed Central

    Stoesser, N; Emary, K; Soklin, S; Peng An, K; Sophal, S; Chhomrath, S; Day, NPJ; Limmathurotsakul, D; Nget, P; Pangnarith, Y; Sona, S; Kumar, V; Moore, CE; Chanpheaktra, N; Parry, CM

    2013-01-01

    Background There are limited data on the epidemiology of paediatric healthcare-associated infection (HCAI) and infection control in low-income countries. We describe the value of intermittent point-prevalence surveys for monitoring HCAI and evaluating infection control interventions in a Cambodian paediatric hospital. Methods Hospital-wide, point-prevalence surveys were performed monthly in 2011. Infection control interventions introduced during this period included a hand hygiene programme and a ventilator-associated pneumonia (VAP) care bundle. Results Overall HCAI prevalence was 13.8/100 patients at-risk, with a significant decline over time. The highest HCAI rates (50%) were observed in critical care; the majority of HCAIs were respiratory (61%). Klebsiella pneumoniae was most commonly isolated and antimicrobial resistance was widespread. Hand hygiene compliance doubled to 51.6%, and total VAP cases/1000 patient-ventilator days fell from 30 to 10. Conclusion Rates of HCAI were substantial in our institution, and antimicrobial resistance a major concern. Point-prevalence surveys are effective for HCAI surveillance, and in monitoring trends in response to infection control interventions. PMID:23418156

  8. End-point control of a two-link manipulator with a very flexible forearm - Issues and experiments

    NASA Technical Reports Server (NTRS)

    Oakley, Celia M.; Cannon, Robert H., Jr.

    1989-01-01

    For mechanical manipulators, a logical sensor location is at the manipulator end-point where tasks are performed. Unfortunately, when bending flexibility exists between an end-point sensor and a joint actuator, stability and performance are achieved only through sophisticated control design. Some of the issues involved in utilizing end-point sensing for two-link flexible manipulators are addressed. A modeling technique that properly represents the foreshortening of a flexible link undergoing deflections is presented. In order to realize fully the advantages of the assumed-modes modeling method, mode shapes are selected that allow a low-order model to be used effectively for simulation and control purposes. A nonlinear controller, incorporating state feedback and a constant-gain extended Kalman filter driven by end-point measurements, is designed and compared to a conventional proportional-plus-derivative controller that uses collocated sensors. Results from implementing these controllers on the experimental Stanford multilink flexible manipulator are given.

  9. Evaluating the role of point source discharges informs statewide nutrient control policy in Utah.

    PubMed

    Daigger, Glen T; Datta, Tania; Stensel, H David; Whitlock, Drury D; Mackey, John K

    2014-06-01

    An evaluation of costs, rate, and environmental impacts of upgrading publically owned treatment works (POTWs) in the State of Utah to four levels of nutrient control allowed a variety of nutrient control policies to be assessed. Upgrade costs and rate impacts indicated that costs would be within a defined range for many POTWs, especially with design capacities greater than 40,000 m3/day (-10 mgd). However, costs were significantly higher for some POTWs with lower design capacities, and nutrient upgrades to the most stringent levels would not be affordable for these communities, representing about 15 percent of the service population. The resulting equity issues can be addressed through hardship grants program and/or regulations based on a trading scheme. Analysis demonstrated that trading offers advantages, including cost efficiency and flexibility to accommodate further nutrient reductions and population growth, and greater ability to interface with urban and rural nonpoint nutrient control. Currently, the State of Utah is establishing technology-based nutrient limits that can be affordably implemented at all POTWs in phases. Additionally, a multi-faceted approach is being evaluated that will consider prioritized watershed-scale strategies, point and nonpoint sources of pollution, ecological and socioeconomic implications, and stakeholder participation in nutrient reduction programs.

  10. The dynamic control ratio at the equilibrium point (DCRe): introducing relative and absolute reliability scores.

    PubMed

    Alt, Tobias; Knicker, Axel J; Strüder, Heiko K

    2017-04-01

    Analytical methods to assess thigh muscle balance need to provide reliable data to allow meaningful interpretation. However, reproducibility of the dynamic control ratio at the equilibrium point has not been evaluated yet. Therefore, the aim of this study was to compare relative and absolute reliability indices of its angle and moment values with conventional and functional hamstring-quadriceps ratios. Furthermore, effects of familiarisation and angular velocity on reproducibility were analysed. A number of 33 male volunteers participated in 3 identical test sessions. Peak moments (PMs) were determined unilaterally during maximum concentric and eccentric knee flexion (prone) and extension (supine position) at 0.53, 1.57 and 2.62 rad · s(-1). A repeated measure, ANOVA, confirmed systematic bias. Intra-class correlation coefficients and standard errors of measurement indicated relative and absolute reliability. Correlation coefficients were averaged over respective factors and tested for significant differences. All balance scores showed comparable low-to-moderate relative (<0.8-0.9) and good absolute reliability (<10%). Relative reproducibility of dynamic control equilibrium parameters augmented with increasing angular velocity, but not with familiarisation. At 2.62 rad · s(-1), high (moment: 0.906) to moderate (angle: 0.833) relative reliability scores with accordingly high absolute indices (4.9% and 6.4%) became apparent. Thus, the dynamic control equilibrium is an equivalent method for the reliable assessment of thigh muscle balance.

  11. Control Point Analysis comparison for 3 different treatment planning and delivery complexity levels using a commercial 3-dimensional diode array

    SciTech Connect

    Abdellatif, Ady; Gaede, Stewart

    2014-07-01

    To investigate the use of “Control Point Analysis” (Sun Nuclear Corporation, Melbourne, FL) to analyze and compare delivered volumetric-modulated arc therapy (VMAT) plans for 3 different treatment planning complexity levels. A total of 30 patients were chosen and fully anonymized for the purpose of this study. Overall, 10 lung stereotactic body radiotherapy (SBRT), 10 head-and-neck (H and N), and 10 prostate VMAT plans were generated on Pinnacle{sup 3} and delivered on a Varian linear accelerator (LINAC). The delivered dose was measured using ArcCHECK (Sun Nuclear Corporation, Melbourne, FL). Each plan was analyzed using “Sun Nuclear Corporation (SNC) Patient 6” and “Control Point Analysis.” Gamma passing percentage was used to assess the differences between the measured and planned dose distributions and to assess the role of various control point binning combinations. Of the different sites considered, the prostate cases reported the highest gamma passing percentages calculated with “SNC Patient 6” (97.5% to 99.2% for the 3%, 3 mm) and “Control Point Analysis” (95.4% to 98.3% for the 3%, 3 mm). The mean percentage of passing control point sectors for the prostate cases increased from 51.8 ± 7.8% for individual control points to 70.6 ± 10.5% for 5 control points binned together to 87.8 ± 11.0% for 10 control points binned together (2%, 2-mm passing criteria). Overall, there was an increasing trend in the percentage of sectors passing gamma analysis with an increase in the number of control points binned together in a sector for both the gamma passing criteria (2%, 2 mm and 3%, 3 mm). Although many plans passed the clinical quality assurance criteria, plans involving the delivery of high Monitor Unit (MU)/control point (SBRT) and plans involving high degree of modulation (H and N) showed less delivery accuracy per control point compared with plans with low MU/control point and low degree of modulation (prostate)

  12. Thermoplastic fusion bonding using a pressure-assisted boiling point control system.

    PubMed

    Park, Taehyun; Song, In-Hyouk; Park, Daniel S; You, Byoung Hee; Murphy, Michael C

    2012-08-21

    A novel thermoplastic fusion bonding method using a pressure-assisted boiling point (PABP) control system was developed to apply precise temperatures and pressures during bonding. Hot embossed polymethyl methacrylate (PMMA) components containing microchannels were sealed using the PABP system. Very low aspect ratio structures (AR = 1/100, 10 μm in depth and 1000 μm in width) were successfully sealed without collapse or deformation. The integrity and strength of the bonds on the sealed PMMA devices were evaluated using leakage and rupture tests; no leaks were detected and failure during the rupture tests occurred at pressures greater than 496 kPa. The PABP system was used to seal 3D shaped flexible PMMA devices successfully.

  13. Mesoscopic capacitor and zero-point energy: Poisson's distribution for virtual charges, pressure, and decoherence control

    NASA Astrophysics Data System (ADS)

    Flores, J. C.

    2014-08-01

    Mesoscopic capacitor theory, which includes intrinsic inductive effects from quantum tunneling, is applied to conducting spherical shells. The zero-point pressure and the number of virtual charged pairs are determined assuming a Poisson distribution. They are completely defined by a dimensionless mesoscopic parameter (χc) measuring the average number of virtual pairs per solid angle and carrying mesoscopic information. Fluctuations remain finite and well defined. Connections with usual quantum-field-theory limit enables us to evaluate χc 1.007110. Equivalently, for a mesoscopic parallel-plate capacitor, the shot noise distribution becomes operative with χc 0.94705 as well being related to the density of virtual pairs. Temperature decoherence and capacitor control are discussed by considering typical values of quantum dot devices and Coulomb blockade theory.

  14. [L-THIA-based management design for controlling urban non-point source pollution].

    PubMed

    Guo, Qing-Hai; Yang, Liu; Ke-Ming, Ma

    2007-11-01

    L-THIA Model was used to simulate the amounts of NPS pollutants in 2 catchments of Sanjiao watershed (Sj1, Sj2) in Hanyang district, and the total simulated amount of NPS loads in Sj1 and Sj2 were 1.82 x 10(4) kg, 1.38 x 10(5) kg, respectively. Based on the theory of resource-sink" and interaction of pattern with process, a series of BMPs, including green roof, grassland, porous pavement, infiltration trench, vegetative filter strip and wet pond, were optimized, and effects of BMPs were simulated along the surface runoff pathway. The results show that total pollutants outputs entering Sj1 and Sj2 account for 14.65% and 6.57%, respectively. Combining L-THIA model and BMPs in series is a proper measure for non-point source pollution control and urban development planning at watershed or region scale.

  15. Quality evaluation of UAV associated digital terrain model by means of ground control points

    NASA Astrophysics Data System (ADS)

    Chang, Kuo-Jen; Huang, Mei-Jen; Lin, Chu-Fen; Hsieh, Yu-Chung

    2015-04-01

    In recent years, Unmanned Aerial Vehicle (UAV) become a popular technology, and is very useful for natural disaster assessment and hazard mitigation study. With good UAV equipment and resources, this study is thus focus on the feasibility and adaptability analysis of the UAV techniques and its' applications. Digital terrain model (DTM) is the one of the most essential data set for hazard analysis. In this study we try to find what the data and the quality that UAV-associated equipment may produce, and the relationship related with the ground control points (GCPs), and what is the most efficient way to improve the quality, and how to achieve this goals. There are two kinds of UAVs, the fixed wing and the rotor wings, depending on different role of classification. In this study, we compare the quality evaluation of DTM from these two kinds of UAV. Different factors are also evaluated in this study, including different kinds of digital cameras, different UAVs, and different sets of GCP groups, by comparing the DTM quality that applying in the same area. The result indicates that the quality of images affects the DTM, and the quality of image relates with, and only with the mission fly high. However, different UAV platform is not important for data resolution. In this study, we analyzed how does GCP affects DTM, compared with the airborne LiDAR data, and with ground leveling. Even caused of the field situations, time costs… etc. we could not set GCP homogeneously and ideally. The result finds the distribution and the amount of the ground control points are the dominant factors affecting DTM quality. The current result shows that the precision of the DTM could be better than 20cm, compared with airborne LiDAR data. Based on the objective of this study, some suggests and results related with different platforms and equipment selection, and the mission planning is thus discussed.

  16. A numerical and experimental investigation of crystalline silica exposure control during tuck pointing.

    PubMed

    Heitbrink, William; Bennett, James

    2006-07-01

    National Institute for Occupational Safety and Health researchers investigated control measures for the removal of mortar between bricks, using a grinder. This task, "tuck pointing," is associated with crystalline silica exposures many times greater than the permissible exposure limit enforced by the Occupational Safety and Health Administration. Previous studies showed that local exhaust ventilation (LEV) of the grinding wheel through a shroud was often ineffective. Tuck pointing occurs on a scaffold. For practical purposes, this limits the size and power of the LEV system. Thus, the goal of this study was to develop a recommended flow rate for exposure control. Flow induced by the rotating grinding wheel, flow induced by the mortar particle stream, and particle momentum are potential control challenges. Computational fluid dynamic (CFD) simulation of the grinder, supported by some experimental measurements, showed the relative importance of these factors through varying parameters and tracking particles. In a simulation of the shroud and grinding wheel, with the wheel inserted to a cutting depth of 0.750 inch flush into the brick wall, -0.461 cubic feet per meter (0.461 into the exhaust takeoff) was induced by the rotating wheel. The more realistic situation of the wheel in a cut in the wall 1.25 inches deep (forming a trench circumferentially 0.500 inch below the wheel edge) induced an airflow of 8.24 cfm out of the shroud exhaust. Experimental measurements taken for validation were 7.3% lower than the CFD value. The trench effect disappeared when a stream of 10-mu m particles was launched from the grinding wheel edge, as the simulations with and without the trench had nearly identical induced flow rates, 10.8 cfm and 10.9 cfm. We thus interpreted the particle stream as more important than the wheel in inducing flow. This insight was possible because of the power of CFD, compared to intuition and classical boundary layer analysis. In this situation of no forced

  17. Sfm_georef: Automating image measurement of ground control points for SfM-based projects

    NASA Astrophysics Data System (ADS)

    James, Mike R.

    2016-04-01

    Deriving accurate DEM and orthomosaic image products from UAV surveys generally involves the use of multiple ground control points (GCPs). Here, we demonstrate the automated collection of GCP image measurements for SfM-MVS processed projects, using sfm_georef software (James & Robson, 2012; http://www.lancaster.ac.uk/staff/jamesm/software/sfm_georef.htm). Sfm_georef was originally written to provide geo-referencing procedures for SfM-MVS projects. It has now been upgraded with a 3-D patch-based matching routine suitable for automating GCP image measurement in both aerial and ground-based (oblique) projects, with the aim of reducing the time required for accurate geo-referencing. Sfm_georef is compatible with a range of SfM-MVS software and imports the relevant files that describe the image network, including camera models and tie points. 3-D survey measurements of ground control are then provided, either for natural features or artificial targets distributed over the project area. Automated GCP image measurement is manually initiated through identifying a GCP position in an image by mouse click; the GCP is then represented by a square planar patch in 3-D, textured from the image and oriented parallel to the local topographic surface (as defined by the 3-D positions of nearby tie points). Other images are then automatically examined by projecting the patch into the images (to account for differences in viewing geometry) and carrying out a sub-pixel normalised cross-correlation search in the local area. With two or more observations of a GCP, its 3-D co-ordinates are then derived by ray intersection. With the 3-D positions of three or more GCPs identified, an initial geo-referencing transform can be derived to relate the SfM-MVS co-ordinate system to that of the GCPs. Then, if GCPs are symmetric and identical, image texture from one representative GCP can be used to search automatically for all others throughout the image set. Finally, the GCP observations can be

  18. Study of the critical points of HPMC hydrophilic matrices for controlled drug delivery.

    PubMed

    Miranda, Antonia; Millán, Mónica; Caraballo, Isidoro

    2006-03-27

    The knowledge of the percolation thresholds of a system results in a clear improvement of the design of controlled release dosage forms such as inert matrices. Despite hydrophilic matrices are one of the most used controlled delivery systems in the world, but actuality, the mechanisms of drug release from these systems continue to be a matter of debate nowadays. The objective of the present paper is to apply the percolation theory to study the release and hydration rate of hydrophilic matrices. Matrix tablets have been prepared using KCl as a drug model and HPMC K4M as matrix-forming material, employing five different excipient/drug particle size ratios (ranging from 0.42 to 2.33). The formulations studied containing a drug loading in the range of 20-90% (w/w). Dissolution studies were carried out using the paddle method and the water uptake measurements were performed using a modified Enslin apparatus. In order to estimate the percolation threshold, the behaviour of the kinetic parameters with respect to the volumetric fraction of each component at time zero, was studied. The percolation theory has been applied for the first time to the study of matrix type controlled delivery systems. The application of this theory allowed to explain changes in the release and hydration kinetics of these matrices. The critical points observed in dissolution and water uptake studies can be attributed to the excipient percolation threshold, being this threshold one of the main factors governing the gel layer formation and consequently, the drug release control from hydrophilic matrices.

  19. A study of attitude control concepts for precision-pointing non-rigid spacecraft

    NASA Technical Reports Server (NTRS)

    Likins, P. W.

    1975-01-01

    Attitude control concepts for use onboard structurally nonrigid spacecraft that must be pointed with great precision are examined. The task of determining the eigenproperties of a system of linear time-invariant equations (in terms of hybrid coordinates) representing the attitude motion of a flexible spacecraft is discussed. Literal characteristics are developed for the associated eigenvalues and eigenvectors of the system. A method is presented for determining the poles and zeros of the transfer function describing the attitude dynamics of a flexible spacecraft characterized by hybrid coordinate equations. Alterations are made to linear regulator and observer theory to accommodate modeling errors. The results show that a model error vector, which evolves from an error system, can be added to a reduced system model, estimated by an observer, and used by the control law to render the system less sensitive to uncertain magnitudes and phase relations of truncated modes and external disturbance effects. A hybrid coordinate formulation using the provided assumed mode shapes, rather than incorporating the usual finite element approach is provided.

  20. Effects of changing gravity on anticipatory grip force control during point-to-point movements of a hand-held object.

    PubMed

    Nowak, D A; Hermsdörfer, J; Philipp, J; Marquardt, C; Glasauer, S; Mai, N

    2001-07-01

    We investigated the quality of predictive grip force control during gravity changes induced by parabolic flight maneuvers. During these maneuvers gravity varied: There were 2 periods of hypergravity, in which terrestrial gravity nearly doubled, and a 20-s period of microgravity, during which a manipulated object was virtually weightless. We determined grip and load forces during vertical point-to-point movements of an instrumented object. Point-to-point movements were a combination of static (stationary holding) and dynamic (continuous movements) task conditions, which were separately analyzed in our previous studies. Analysis of the produced grip forces revealed that grip adjustments were closely linked to load force fluctuations under each gravity condition. In particular, grip force maxima coincided closely in time with load force peaks, although these occurred at different phases of the movement depending on the gravity level. However, quantitative analysis of the ratio of maximum grip force to the corresponding load force peak revealed an increased force ratio during microgravity when compared to that during normal and hypergravity. We hypothesize that the impaired precision of force coupling with respect to force magnitude during microgravity results from reduced feedback information about the object's mass during the stationary holding of the object in between each movement. The results indicate that the temporal grip force regulation is highly automatized and stable, whereas economical planning of force magnitude is more flexible and might reflect changes of the external loading condition.

  1. Optical tools and techniques for aligning solar payloads with the SPARCS control system. [Solar Pointing Aerobee Rocket Control System

    NASA Technical Reports Server (NTRS)

    Thomas, N. L.; Chisel, D. M.

    1976-01-01

    The success of a rocket-borne experiment depends not only on the pointing of the attitude control system, but on the alignment of the attitude control system to the payload. To ensure proper alignment, special optical tools and alignment techniques are required. Those that were used in the SPARCS program are described and discussed herein. These tools include theodolites, autocollimators, a 38-cm diameter solar simulator, a high-performance 1-m heliostat to provide a stable solar source during the integration of the rocket payload, a portable 75-cm sun tracker for use at the launch site, and an innovation called the Solar Alignment Prism. Using the real sun as the primary reference under field conditions, the Solar Alignment Prism facilitates the coalignment of the attitude sun sensor with the payload. The alignment techniques were developed to ensure the precise alignment of the solar payloads to the SPARCS attitude sensors during payload integration and to verify the required alignment under field conditions just prior to launch.

  2. Distinct transcriptional control in major immunogenetic subsets of chronic lymphocytic leukemia exhibiting subset-biased global DNA methylation profiles

    PubMed Central

    Kanduri, Meena; Marincevic, Millaray; Halldórsdóttir, Anna M.; Mansouri, Larry; Junevik, Katarina; Ntoufa, Stavroula; Kultima, Hanna Göransson; Isaksson, Anders; Juliusson, Gunnar; Andersson, Per-Ola; Ehrencrona, Hans; Stamatopoulos, Kostas; Rosenquist, Richard

    2012-01-01

    Chronic lymphocytic leukemia (CLL) can be divided into prognostic subgroups based on the IGHV gene mutational status, and is further characterized by multiple subsets of cases with quasi-identical or stereotyped B cell receptors that also share clinical and biological features. We recently reported differential DNA methylation profiles in IGHV-mutated and IGHV-unmutated CLL subgroups. For the first time, we here explore the global methylation profiles of stereotyped subsets with different prognosis, by applying high-resolution methylation arrays on CLL samples from three major stereotyped subsets: the poor-prognostic subsets #1 (n = 15) and #2 (n = 9) and the favorable-prognostic subset #4 (n = 15). Overall, the three subsets exhibited significantly different methylation profiles, which only partially overlapped with those observed in our previous study according to IGHV gene mutational status. Specifically, gene ontology analysis of the differentially methylated genes revealed a clear enrichment of genes involved in immune response, such as B cell activation (e.g., CD80, CD86 and IL10), with higher methylation levels in subset #1 than subsets #2 and #4. Accordingly, higher expression of the co-stimulatory molecules CD80 and CD86 was demonstrated in subset #4 vs. subset #1, pointing to a key role for these molecules in the crosstalk of CLL subset #4 cells with the microenvironment. In summary, investigation of three prototypic, stereotyped CLL subsets revealed distinct DNA methylation profiles for each subset, which suggests subset-biased patterns of transcriptional control and highlights a key role for epigenetics during leukemogenesis. PMID:23154584

  3. Distinct transcriptional control in major immunogenetic subsets of chronic lymphocytic leukemia exhibiting subset-biased global DNA methylation profiles.

    PubMed

    Kanduri, Meena; Marincevic, Millaray; Halldórsdóttir, Anna M; Mansouri, Larry; Junevik, Katarina; Ntoufa, Stavroula; Kultima, Hanna Göransson; Isaksson, Anders; Juliusson, Gunnar; Andersson, Per-Ola; Ehrencrona, Hans; Stamatopoulos, Kostas; Rosenquist, Richard

    2012-12-01

    Chronic lymphocytic leukemia (CLL) can be divided into prognostic subgroups based on the IGHV gene mutational status, and is further characterized by multiple subsets of cases with quasi-identical or stereotyped B cell receptors that also share clinical and biological features. We recently reported differential DNA methylation profiles in IGHV-mutated and IGHV-unmutated CLL subgroups. For the first time, we here explore the global methylation profiles of stereotyped subsets with different prognosis, by applying high-resolution methylation arrays on CLL samples from three major stereotyped subsets: the poor-prognostic subsets #1 (n = 15) and #2 (n = 9) and the favorable-prognostic subset #4 (n = 15). Overall, the three subsets exhibited significantly different methylation profiles, which only partially overlapped with those observed in our previous study according to IGHV gene mutational status. Specifically, gene ontology analysis of the differentially methylated genes revealed a clear enrichment of genes involved in immune response, such as B cell activation (e.g., CD80, CD86 and IL10), with higher methylation levels in subset #1 than subsets #2 and #4. Accordingly, higher expression of the co-stimulatory molecules CD80 and CD86 was demonstrated in subset #4 vs. subset #1, pointing to a key role for these molecules in the crosstalk of CLL subset #4 cells with the microenvironment. In summary, investigation of three prototypic, stereotyped CLL subsets revealed distinct DNA methylation profiles for each subset, which suggests subset-biased patterns of transcriptional control and highlights a key role for epigenetics during leukemogenesis.

  4. Environment and vulnerability to major psychiatric illness: a case control study of early parental loss in major depression, bipolar disorder and schizophrenia.

    PubMed

    Agid, O; Shapira, B; Zislin, J; Ritsner, M; Hanin, B; Murad, H; Troudart, T; Bloch, M; Heresco-Levy, U; Lerer, B

    1999-03-01

    The current focus on identifying genes which predispose to psychiatric illness sharpens the need to identify environmental factors which interact with genetic predisposition and thus contribute to the multifactorial causation of these disorders. One such factor may be early parental loss (EPL). The putative relationship between early environmental stressors such as parental loss and psychopathology in adult life has intrigued psychiatrists for most of this century. We report a case control study in which rates of EPL, due to parental death or permanent separation before the age of 17 years were evaluated in patients with major depression (MD), bipolar disorder (BPD) and schizophrenia (SCZ), compared to individually matched, healthy control subjects (MD-Control, 79 pairs; BPD-Control, 79 pairs; SCZ-Control, 76 pairs). Loss of parent during childhood significantly increased the likelihood of developing MD during adult life (OR=3.8, P=0.001). The effect of loss due to permanent separation (P=0.008) was more striking than loss due to death, as was loss before the age of 9 years (OR=11.0, P=0.003) compared to later childhood and adolescence. The overall rate of EPL was also increased in BPD (OR=2.6, P=0.048) but there were no significant findings in any of the subcategories of loss. A significantly increased rate of EPL was observed in schizophrenia patients (OR=3.8, P=0.01), particularly before the age of 9 years (OR=4.3, P=0.01). Comparison of psychosocial, medical and clinical characteristics of subjects with and without a history of EPL, within the larger patient groups from which the matched samples were drawn (MD, n=136; BPD, n=107; SCZ, n=160), yielded few significant findings. Among the controls (n=170), however, subjects who had experienced EPL, reported lower incomes, had been divorced more frequently, were more likely to be living alone, were more likely to smoke or have smoked cigarettes and reported more physical illness (P=0.03-0.001). Long term

  5. Raoult’s law revisited: accurately predicting equilibrium relative humidity points for humidity control experiments

    PubMed Central

    Bowler, Michael G.

    2017-01-01

    The humidity surrounding a sample is an important variable in scientific experiments. Biological samples in particular require not just a humid atmosphere but often a relative humidity (RH) that is in equilibrium with a stabilizing solution required to maintain the sample in the same state during measurements. The controlled dehydration of macromolecular crystals can lead to significant increases in crystal order, leading to higher diffraction quality. Devices that can accurately control the humidity surrounding crystals while monitoring diffraction have led to this technique being increasingly adopted, as the experiments become easier and more reproducible. Matching the RH to the mother liquor is the first step in allowing the stable mounting of a crystal. In previous work [Wheeler, Russi, Bowler & Bowler (2012). Acta Cryst. F68, 111–114], the equilibrium RHs were measured for a range of concentrations of the most commonly used precipitants in macromolecular crystallography and it was shown how these related to Raoult’s law for the equilibrium vapour pressure of water above a solution. However, a discrepancy between the measured values and those predicted by theory could not be explained. Here, a more precise humidity control device has been used to determine equilibrium RH points. The new results are in agreement with Raoult’s law. A simple argument in statistical mechanics is also presented, demonstrating that the equilibrium vapour pressure of a solvent is proportional to its mole fraction in an ideal solution: Raoult’s law. The same argument can be extended to the case where the solvent and solute molecules are of different sizes, as is the case with polymers. The results provide a framework for the correct maintenance of the RH surrounding a sample. PMID:28381983

  6. Raoult's law revisited: accurately predicting equilibrium relative humidity points for humidity control experiments.

    PubMed

    Bowler, Michael G; Bowler, David R; Bowler, Matthew W

    2017-04-01

    The humidity surrounding a sample is an important variable in scientific experiments. Biological samples in particular require not just a humid atmosphere but often a relative humidity (RH) that is in equilibrium with a stabilizing solution required to maintain the sample in the same state during measurements. The controlled dehydration of macromolecular crystals can lead to significant increases in crystal order, leading to higher diffraction quality. Devices that can accurately control the humidity surrounding crystals while monitoring diffraction have led to this technique being increasingly adopted, as the experiments become easier and more reproducible. Matching the RH to the mother liquor is the first step in allowing the stable mounting of a crystal. In previous work [Wheeler, Russi, Bowler & Bowler (2012). Acta Cryst. F68, 111-114], the equilibrium RHs were measured for a range of concentrations of the most commonly used precipitants in macromolecular crystallography and it was shown how these related to Raoult's law for the equilibrium vapour pressure of water above a solution. However, a discrepancy between the measured values and those predicted by theory could not be explained. Here, a more precise humidity control device has been used to determine equilibrium RH points. The new results are in agreement with Raoult's law. A simple argument in statistical mechanics is also presented, demonstrating that the equilibrium vapour pressure of a solvent is proportional to its mole fraction in an ideal solution: Raoult's law. The same argument can be extended to the case where the solvent and solute molecules are of different sizes, as is the case with polymers. The results provide a framework for the correct maintenance of the RH surrounding a sample.

  7. Ground Control Point - Wireless System Network for UAV-based environmental monitoring applications

    NASA Astrophysics Data System (ADS)

    Mejia-Aguilar, Abraham

    2016-04-01

    In recent years, Unmanned Aerial Vehicles (UAV) have seen widespread civil applications including usage for survey and monitoring services in areas such as agriculture, construction and civil engineering, private surveillance and reconnaissance services and cultural heritage management. Most aerial monitoring services require the integration of information acquired during the flight (such as imagery) with ground-based information (such as GPS information or others) for improved ground truth validation. For example, to obtain an accurate 3D and Digital Elevation Model based on aerial imagery, it is necessary to include ground-based information of coordinate points, which are normally acquired with surveying methods based on Global Position Systems (GPS). However, GPS surveys are very time consuming and especially for longer time series of monitoring data repeated GPS surveys are necessary. In order to improve speed of data collection and integration, this work presents an autonomous system based on Waspmote technologies build on single nodes interlinked in a Wireless Sensor Network (WSN) star-topology for ground based information collection and later integration with surveying data obtained by UAV. Nodes are designed to be visible from the air, to resist extreme weather conditions with low-power consumption. Besides, nodes are equipped with GPS as well as Inertial Measurement Unit (IMU), accelerometer, temperature and soil moisture sensors and thus provide significant advantages in a broad range of applications for environmental monitoring. For our purpose, the WSN transmits the environmental data with 3G/GPRS to a database on a regular time basis. This project provides a detailed case study and implementation of a Ground Control Point System Network for UAV-based vegetation monitoring of dry mountain grassland in the Matsch valley, Italy.

  8. Auricular Acupressure on Specific Points for Hemodialysis Patients with Insomnia: A Pilot Randomized Controlled Trial

    PubMed Central

    Wu, Yuchi; Su, Guobin; Chen, Shuhui; Guo, Xinfeng; Wu, Xiuqing; Liu, Xusheng; Lin, Qizhan

    2015-01-01

    Objectives To assess the feasibility and acceptability of a randomized controlled trial compared auricular acupressure (AA) on specific acupoints with AA on non-specific acupoints for treating maintenance hemodialysis (MHD) patients with insomnia. Methods Sixty three (63) eligible subjects were randomly assigned into either AA group received AA on specific acupoints (n=32), or sham AA (SAA) group received AA on points irrelevant to insomnia treatment (n=31) for eight weeks. All participants were followed up for 12 weeks after treatments. The primary outcome was clinical response at eight weeks after randomization, defined as a reduction of Pittsburgh Sleep Quality Index (PSQI) global score by 3 points and more. Results Fifty-eight (58) participants completed the trial and five dropped out. Twenty participants in AA group (62.5%) and ten in SAA group (32.3%) responded to the eight-week interventions (χ2 = 5.77, P = 0.02). PSQI global score declined 3.75 ± 4.36 (95%CI -5.32, -2.18) and 2.26 ± 3.89 (95%CI -3.68, -0.83) in AA group and SAA group respectively. Three participants died during the follow-up period. No evidence supported their deaths were related to the AA intervention. No other adverse event was observed. Conclusion Feasibility and logistics of patient recruitment, randomization procedure, blinding approach, interventions application and outcome assessment had been tested in this pilot trial. The preliminary data appeared to show a favorable result on AA treatment. A full-scale trial is warranted. Trial Registration Chinese Clinical Trial Registry ChiCTR-TRC-12002272. PMID:25874938

  9. Major Andre

    ERIC Educational Resources Information Center

    Henisch, B. A.; Henisch, H. K.

    1976-01-01

    If most Revolutionary era people seem two-dimensional their lives simpler to understand than ours, it may be only that history, with the benefit of hindsight, clarifies. Examines a profile of Major John Andre, the British liaison officer in Benedict Arnold's plan to surrender West Point, as both hero and villain to show the complexity of early…

  10. Optimization strategy integrity for watershed agricultural non-point source pollution control based on Monte Carlo simulation

    NASA Astrophysics Data System (ADS)

    Gong, Y.; Yu, Y. J.; Zhang, W. Y.

    2016-08-01

    This study has established a set of methodological systems by simulating loads and analyzing optimization strategy integrity for the optimization of watershed non-point source pollution control. First, the source of watershed agricultural non-point source pollution is divided into four aspects, including agricultural land, natural land, livestock breeding, and rural residential land. Secondly, different pollution control measures at the source, midway and ending stages are chosen. Thirdly, the optimization effect of pollution load control in three stages are simulated, based on the Monte Carlo simulation. The method described above is applied to the Ashi River watershed in Heilongjiang Province of China. Case study results indicate that the combined three types of control measures can be implemented only if the government promotes the optimized plan and gradually improves implementation efficiency. This method for the optimization strategy integrity for watershed non-point source pollution control has significant reference value.

  11. Free-time and fixed end-point optimal control theory in quantum mechanics: application to entanglement generation.

    PubMed

    Mishima, K; Yamashita, K

    2009-01-21

    We have constructed free-time and fixed end-point optimal control theory for quantum systems and applied it to entanglement generation between rotational modes of two polar molecules coupled by dipole-dipole interaction. The motivation of the present work is to solve optimal control problems more flexibly by extending the popular fixed time and fixed end-point optimal control theory for quantum systems to free-time and fixed end-point optimal control theory. As a demonstration, the theory that we have constructed in this paper will be applied to entanglement generation in rotational modes of NaCl-NaBr polar molecular systems that are sensitive to the strength of entangling interactions. Our method will significantly be useful for the quantum control of nonlocal interaction such as entangling interaction, which depends crucially on the strength of the interaction or the distance between the two molecules, and other general quantum dynamics, chemical reactions, and so on.

  12. Free-time and fixed end-point optimal control theory in quantum mechanics: Application to entanglement generation

    NASA Astrophysics Data System (ADS)

    Mishima, K.; Yamashita, K.

    2009-01-01

    We have constructed free-time and fixed end-point optimal control theory for quantum systems and applied it to entanglement generation between rotational modes of two polar molecules coupled by dipole-dipole interaction. The motivation of the present work is to solve optimal control problems more flexibly by extending the popular fixed time and fixed end-point optimal control theory for quantum systems to free-time and fixed end-point optimal control theory. As a demonstration, the theory that we have constructed in this paper will be applied to entanglement generation in rotational modes of NaCl-NaBr polar molecular systems that are sensitive to the strength of entangling interactions. Our method will significantly be useful for the quantum control of nonlocal interaction such as entangling interaction, which depends crucially on the strength of the interaction or the distance between the two molecules, and other general quantum dynamics, chemical reactions, and so on.

  13. Plasma glycine and serine levels in schizophrenia compared to normal controls and major depression: relation to negative symptoms.

    PubMed

    Sumiyoshi, Tomiki; Anil, A Elif; Jin, Dai; Jayathilake, Karu; Lee, Myung; Meltzer, Herbert Y

    2004-03-01

    Previous studies have suggested decreased N-methyl-D-aspartate (NMDA)-type glutamate receptor function may contribute to increased negative symptoms in patients with schizophrenia. Consistent with this hypothesis, glycine, a co-agonist at NMDA receptors, has been reported to improve negative symptoms associated with the illness. This study was performed to determine if plasma levels of glycine or its ratio to serine, a precursor of glycine, are decreased in patients with schizophrenia compared to normal control subjects or patients with major depression. We also tested the hypothesis that these amino acids were correlated with negative symptoms in subjects with schizophrenia. Plasma levels of glycine, serine, and their ratio, were compared in 144 patients with schizophrenia, 44 patients with major depression, and 49 normal control subjects. All subjects were medication-free. Psychopathology was evaluated using the Brief Psychiatric Rating Scale (BPRS). Plasma glycine levels and glycine/serine ratios were decreased in patients with schizophrenia relative to control subjects and patients with major depression. By contrast, serine levels were increased in patients with schizophrenia compared to normal subjects but not compared to major depression. Patients with major depression also had increased plasma serine levels and decreased glycine/serine ratios compared to normal controls, but glycine levels were not different from those of normal controls. In subjects with schizophrenia, glycine levels predicted the Withdrawal-Retardation score (BPRS), whereas no such correlation was found in subjects with major depression. These results provide additional evidence that decreased availability of glycine may be related to the pathophysiology of negative symptoms. The decreases in plasma glycine levels support the evidence for an abnormality in the glutamatergic system in schizophrenia, and provide additional support for efforts to improve negative symptoms by augmentation of

  14. Topical treatment of major omphalocoele: Acacia nilotica versus povidone-iodine: A randomised controlled study

    PubMed Central

    Eltayeb, Almoutaz A.; Mostafa, Mahmoud M.

    2015-01-01

    Background: Conservative management for major omphalocoele with topical agents as escharotics therapy is well established in practice. Different agents have been used in the past, including mercurochrome and alcohol, proved later to be unsafe. The aim of this study is to evaluate the efficacy and safety of the application of Acacia nilotica paste compared to povidone-iodine solution as a primary non-surgical treatment of major omphalocoele. Patients and Methods: A double-blind, randomised study was conducted on 24 cases of major omphalocoele where they were randomly divided into two equal groups; Group A treated with topical application of A. nilotica paste and Group B treated with topical application of povidone-iodine solution. Cases with gastroschisis, ruptured major omphalocoele or minor omphalocoele were excluded from the study. The evaluating parameters were size of the fascial defect in cm, period of mechanical ventilation if needed, time required for full oral feeding tolerance, duration of hospital stay and any short- or long-term complications. Results: There was no statistical significant difference between both groups regarding their gestational or post-natal age, weight and the mean umbilical port defect. Patients from Group A tolerated full oral feeding earlier and had shorter total hospital stay duration than those from Group B, but without a statistical significant difference (P = 0.347 and 0.242, respectively). The overall mortality rate was 33.3% without a statistical significant difference between both groups (P = 0.667). Conclusions: Application of A. nilotica is a safe and effective treatment of major omphalocoele as it was associated with rapid full enteral feeding tolerance, short duration of hospital stay and low mortality rate. PMID:26712288

  15. Preliminary study on hazards and critical control points of kokoro, a Nigerian indigenous fermented maize snack.

    PubMed

    Oranusi, S; Dahunsi, S O

    2015-01-01

    The microbial and proximate composition of an indigenous snack from fermented maize was investigated. Critical control points of milling the raw materials, fermentation pH, processing temperature and time intervals during holdings in processing and storage were evaluated with a view to optimizing the product. The mean total aerobic plate count (TAPC) log10 values for samples of the finished products range from 2.07 ± 0.50 to 4.36 ± 0.10 cfu/g. Mean fungi count log10 was 2.00 ± 0.00 to 3.50 ± 0.50 while mean coliform count 1.04 ± 0.10 log10 cfu/g was detected in one of the sales outlets investigated. Bacterial and fungal species were isolated belonging to the genera Aspergillus, Rhizopus, Penicillium, Fusarium, Cephalosporium, Alternaria, Bacillus, Klebsiella, Staphylococcus, Lactobacillus, Pseudomonas, Proteus and Enterobacter. The moisture content of the samples ranged from 3.41 to 6.75%; fat content was 19.68 to 32.59%; fiber content was 1.84 to 2.78% while protein ranged from 6.76 to 9.23%. The ash and carbohydrate contents ranged from 1.97 to 2.31% and 49.21 to 61.96%, respectively. Based on the specifications by International Commission for Microbiological Specification for Foods (ICMSF), the TAPC counts of the finished products remained at low levels. However, presence of coliforms could prejudice the hygienic quality of these types of products hence, the need for quality control.

  16. The development of an UAV borne direct georeferenced photogrammetric platform for Ground Control Point free applications.

    PubMed

    Chiang, Kai-Wei; Tsai, Meng-Lun; Chu, Chien-Hsun

    2012-01-01

    To facilitate applications such as environment detection or disaster monitoring, the development of rapid low cost systems for collecting near real time spatial information is very critical. Rapid spatial information collection has become an emerging trend for remote sensing and mapping applications. In this study, a fixed-wing Unmanned Aerial Vehicle (UAV)-based spatial information acquisition platform that can operate in Ground Control Point (GCP) free environments is developed and evaluated. The proposed UAV based photogrammetric platform has a Direct Georeferencing (DG) module that includes a low cost Micro Electro Mechanical Systems (MEMS) Inertial Navigation System (INS)/Global Positioning System (GPS) integrated system. The DG module is able to provide GPS single frequency carrier phase measurements for differential processing to obtain sufficient positioning accuracy. All necessary calibration procedures are implemented. Ultimately, a flight test is performed to verify the positioning accuracy in DG mode without using GCPs. The preliminary results of positioning accuracy in DG mode illustrate that horizontal positioning accuracies in the x and y axes are around 5 m at 300 m flight height above the ground. The positioning accuracy of the z axis is below 10 m. Therefore, the proposed platform is relatively safe and inexpensive for collecting critical spatial information for urgent response such as disaster relief and assessment applications where GCPs are not available.

  17. Geometric Positioning for Satellite Imagery without Ground Control Points by Exploiting Repeated Observation.

    PubMed

    Ma, Zhenling; Wu, Xiaoliang; Yan, Li; Xu, Zhenliang

    2017-01-26

    With the development of space technology and the performance of remote sensors, high-resolution satellites are continuously launched by countries around the world. Due to high efficiency, large coverage and not being limited by the spatial regulation, satellite imagery becomes one of the important means to acquire geospatial information. This paper explores geometric processing using satellite imagery without ground control points (GCPs). The outcome of spatial triangulation is introduced for geo-positioning as repeated observation. Results from combining block adjustment with non-oriented new images indicate the feasibility of geometric positioning with the repeated observation. GCPs are a must when high accuracy is demanded in conventional block adjustment; the accuracy of direct georeferencing with repeated observation without GCPs is superior to conventional forward intersection and even approximate to conventional block adjustment with GCPs. The conclusion is drawn that taking the existing oriented imagery as repeated observation enhances the effective utilization of previous spatial triangulation achievement, which makes the breakthrough for repeated observation to improve accuracy by increasing the base-height ratio and redundant observation. Georeferencing tests using data from multiple sensors and platforms with the repeated observation will be carried out in the follow-up research.

  18. A class of multiplicity adjusted tests for spatial clustering based on case-control point data.

    PubMed

    Tango, Toshiro

    2007-03-01

    A class of tests with quadratic forms for detecting spatial clustering of health events based on case-control point data is proposed. It includes Cuzick and Edwards's test statistic (1990, Journal of the Royal Statistical Society, Series B 52, 73-104). Although they used the property of asymptotic normality of the test statistic, we show that such an approximation is generally poor for moderately large sample sizes. Instead, we suggest a central chi-square distribution as a better approximation to the asymptotic distribution of the test statistic. Furthermore, not only to estimate the optimal value of the unknown parameter on the scale of cluster but also to adjust for multiple testing due to repeating the procedure by changing the parameter value, we propose the minimum of the profile p-value of the test statistic for the parameter as an integrated test statistic. We also provide a statistic to estimate the areas or cases which make large contributions to significant clustering. The proposed methods are illustrated with a data set concerning the locations of cases of childhood leukemia and lymphoma and another on early medieval grave site locations consisting of affected and nonaffected grave sites.

  19. Transcutaneous electric acupoint stimulation at Jiaji points reduce abdominal pain after colonoscopy: a randomized controlled trial

    PubMed Central

    Chen, Yanqing; Wu, Weilan; Yao, Yusheng; Yang, Yang; Zhao, Qiuyan; Qiu, Liangcheng

    2015-01-01

    Background: Transcutaneous electric acupoint stimulation (TEAS) at Jiaji acupuncture points has therapeutic potential for relieving viscera pain and opioid-related side effects. This prospective, randomized, triple-blinded, placebo-controlled trial was to investigate the efficacy of TEAS on abdominal pain after colonoscopy. Methods: Consecutive outpatients with American Society of Anesthesiologists (ASA) physical status I or II underwent selective colonoscopy were randomly assigned into two groups for either TEAS or sham pretreatment. The primary outcomes were the incidence of abdominal pain after colonoscopy. The secondary outcomes included the incidence of abdominal distension, postoperative nausea and vomiting (PONV), duration of PACU stay, and patient’s satisfaction and acceptance. Results: Among the 229 patients analyzed, fewer occurrence of post-procedural abdominal pain (11.4% vs 25.2%, P = 0.007) and distension (1.8% vs 7.8%, P = 0.032) were observed in TEAS group, when compared with the sham group. The duration of PACU stay was significant shortened in TEAS group (P < 0.001). Meanwhile, patients’ satisfaction score to medical service was higher (P < 0.001), and their acceptance to colonoscopy was improved (P = 0.011). Conclusion: Pretreatment with TEAS can reduce post-procedural discomfort, provide more efficient medical resources utilization, and improved patient’s satisfaction and colonoscopy acceptance. PMID:26131193

  20. High-accuracy stereo matching based on adaptive ground control points.

    PubMed

    Chenbo Shi; Guijin Wang; Xuanwu Yin; Xiaokang Pei; Bei He; Xinggang Lin

    2015-04-01

    This paper proposes a novel high-accuracy stereo matching scheme based on adaptive ground control points (AdaptGCP). Different from traditional fixed GCP-based methods, we consider color dissimilarity, spatial relation, and the pixel-matching reliability to select GCP adaptively in each local support window. To minimize the global energy, we propose a practical solution, named as alternating updating scheme of disparity and confidence map, which can effectively eliminate the redundant and interfering information of unreliable pixels. The disparity values of those unreliable pixels are reassigned with the information provided by local plane model, which is fitted with GCPs. Then, the confidence map is updated according to the disparity reassignment and the left-right consistency. Finally, the disparity map is refined by multistep filers. Quantitative evaluations demonstrate the effectiveness of our AdaptGCP scheme for regularizing the ill-posed matching problem. The top ranks on Middlebury benchmark with different error thresholds show that our algorithm achieves the state-of-the-art performance among the latest stereo matching algorithms. This paper provides a new insight toward high-accuracy stereo matching.

  1. Geometric Positioning for Satellite Imagery without Ground Control Points by Exploiting Repeated Observation

    PubMed Central

    Ma, Zhenling; Wu, Xiaoliang; Yan, Li; Xu, Zhenliang

    2017-01-01

    With the development of space technology and the performance of remote sensors, high-resolution satellites are continuously launched by countries around the world. Due to high efficiency, large coverage and not being limited by the spatial regulation, satellite imagery becomes one of the important means to acquire geospatial information. This paper explores geometric processing using satellite imagery without ground control points (GCPs). The outcome of spatial triangulation is introduced for geo-positioning as repeated observation. Results from combining block adjustment with non-oriented new images indicate the feasibility of geometric positioning with the repeated observation. GCPs are a must when high accuracy is demanded in conventional block adjustment; the accuracy of direct georeferencing with repeated observation without GCPs is superior to conventional forward intersection and even approximate to conventional block adjustment with GCPs. The conclusion is drawn that taking the existing oriented imagery as repeated observation enhances the effective utilization of previous spatial triangulation achievement, which makes the breakthrough for repeated observation to improve accuracy by increasing the base-height ratio and redundant observation. Georeferencing tests using data from multiple sensors and platforms with the repeated observation will be carried out in the follow-up research. PMID:28134779

  2. The Development of an UAV Borne Direct Georeferenced Photogrammetric Platform for Ground Control Point Free Applications

    PubMed Central

    Chiang, Kai-Wei; Tsai, Meng-Lun; Chu, Chien-Hsun

    2012-01-01

    To facilitate applications such as environment detection or disaster monitoring, the development of rapid low cost systems for collecting near real time spatial information is very critical. Rapid spatial information collection has become an emerging trend for remote sensing and mapping applications. In this study, a fixed-wing Unmanned Aerial Vehicle (UAV)-based spatial information acquisition platform that can operate in Ground Control Point (GCP) free environments is developed and evaluated. The proposed UAV based photogrammetric platform has a Direct Georeferencing (DG) module that includes a low cost Micro Electro Mechanical Systems (MEMS) Inertial Navigation System (INS)/Global Positioning System (GPS) integrated system. The DG module is able to provide GPS single frequency carrier phase measurements for differential processing to obtain sufficient positioning accuracy. All necessary calibration procedures are implemented. Ultimately, a flight test is performed to verify the positioning accuracy in DG mode without using GCPs. The preliminary results of positioning accuracy in DG mode illustrate that horizontal positioning accuracies in the x and y axes are around 5 m at 300 m flight height above the ground. The positioning accuracy of the z axis is below 10 m. Therefore, the proposed platform is relatively safe and inexpensive for collecting critical spatial information for urgent response such as disaster relief and assessment applications where GCPs are not available. PMID:23012538

  3. Heliocentric trajectory analysis of Sun-pointing smart dust with electrochromic control

    NASA Astrophysics Data System (ADS)

    Mengali, Giovanni; Quarta, Alessandro A.

    2016-02-01

    A smart dust is a micro spacecraft, with a characteristic side length on the order of a few millimeters, whose surface is coated with electrochromic material. Its orbital dynamics is controlled by exploiting the differential force due to the solar radiation pressure, which is obtained by modulating the reflectivity coefficient of the electrochromic material within a range of admissible values. A significant thrust level can be reached due to the high values of area-to-mass ratio of such a spacecraft configuration. Assuming that the smart dust is designed to achieve a passive Sun-pointing attitude, the propulsive acceleration due to the solar radiation pressure lies along the Sun-spacecraft direction. The aim of this paper is to study the smart dust heliocentric dynamics in order to find a closed form, analytical solution of its trajectory when the reflectivity coefficient of the electrochromic material can assume two values only. The problem is addressed by introducing a suitable transformation that regularizes the spacecraft motion and translates the smart-dust dynamics into that of a linear harmonic oscillator with unitary frequency, whose forcing input is a boxcar function. The solution is found using the Laplace transform method, and afterwards the problem is generalized by accounting for the degradation of the electrochromic material due to its exposition to the solar radiation. Three spacecraft configurations, corresponding to low, medium and high performance smart dusts, are finally used to quantify the potentialities of these advanced devices in an interplanetary mission scenario.

  4. A Non-Linear Approach to Spacecraft Formation Control in the Vicinity of a Collinear Libration Point

    NASA Technical Reports Server (NTRS)

    Luquette, Richard J.; Sanner, Robert M.; Bauer, Frank H. (Technical Monitor)

    2001-01-01

    An expanding interest in mission design strategies that exploit libration point regions, demands the continued development of enhanced, efficient, control algorithms for station-keeping and formation maintenance. Linear control strategies have been developed for station-keeping. However, their region of stability is bounded by the assumptions required for linearizing the governing equations of motion. For example, reference [I] discusses the development of a linear control design for maintaining a halo orbit about the Earth-Moon L2 libration point. Trial runs indicated the trajectory was unstable for starting points exceeding 45,000 km from the L2 point. Also, there was significant growth in the control effort required to maintain the orbit as the nominal radius increased. This result is a consequence of the increased influence of the system non-linearities, as the trajectory deviated from the linearization point, L2. As an alternative, this paper presents the development of a non-linear control strategy, based on a Hamiltonian formulation of the equations of motion. The control strategy is applied to the problem of formation maintenance, rather than simple station

  5. Decentralized Control of Centipede-like Multi-legged Robots with Passive Intersegment Joints Based on Follow-the-Contact-Point Gait Control

    NASA Astrophysics Data System (ADS)

    Inagaki, Shinkichi; Niwa, Tomoya; Suzuki, Tatsuya

    This paper proposes a novel locomotion control, called Follow-the-Contact-Point (FCP) gait control, for a centipede-like multi-legged robot. The centipede-like multi-legged robot is composed by connecting segments, which have a trunk and a pair of legs, via a passive joint. This control method is motivated from behavioral knowledge of a centipede that each leg always contacts on the point which the anterior leg contacted. The FCP gait control realizes the walking behavior of centipede via decentralized event-driven control structure. In addition, merely by planning and allocating the contact point of legs of a head segment adequately, the robot can change the moving direction and also climb over an obstacle. We clarify the feasibility of the FCP gait control by showing the result of physical simulation of a 20-legged robot.

  6. Optimal maneuvering and fine pointing control of large space telescope with a new magnetically suspended, single gimballed momentum storage device

    NASA Technical Reports Server (NTRS)

    Nadkarni, A. A.; Joshi, S. M.

    1976-01-01

    This paper considers the application of an Annular Momentum Control Device (AMCD) to both fine pointing and large-angle maneuvering of a large space telescope (LST). The AMCD, which consists principally of a spinning rim suspended in noncontacting electromagnetic bearings, represents a new development in momentum storage devices. A nonlinear mathematical model of the AMCD/LST system is derived. An optimal stochastic fine-pointing controller is designed via LQG theory and the minimum-energy maneuvering problem is solved via a gradient technique. Number of state variable and control variable constraints, as well as all trigonometric nonlinearities, are considered in the latter part.

  7. A Non-Linear Approach to Spacecraft Formation Control in the Vicinity of a Collinear Libration Point

    NASA Technical Reports Server (NTRS)

    Luquette, Richard J.; Sanner, Robert M.; Bauer, Frank H. (Technical Monitor)

    2001-01-01

    An expanding interest in mission design strategies that exploit libration point regions demands the continued development of enhanced, efficient, control algorithms for station-keeping and formation maintenance. This paper discusses the development of a non-linear, formation maintenance, control algorithm for trajectories in the vicinity of a libration point. However, the formulation holds for any trajectory governed by the equations of motion for the restricted three body problem. The control law guarantees exponential convergence, based on a Lyaponov analysis. FreeFlyer and MATLAB provide the simulation environment for controller performance evaluation. The simulation, modeled after the MAXIM Pathfinder mission, maintains the relative position of a "follower" spacecraft with respect to a "leader" spacecraft, stationed near the L2 libration point in the Sun-Earth system. Evaluation metrics are fuel usage and tracking accuracy.

  8. Desferrioxamine Attenuates Pancreatic Injury after Major Hepatectomy under Vascular Control of the Liver: Experimental Study in Pigs

    PubMed Central

    Varsos, Panagiotis; Nastos, Constantinos; Papoutsidakis, Nikolaos; Kalimeris, Konstantinos; Defterevos, George; Nomikos, Tzortzis; Pafiti, Agathi; Fragulidis, George; Economou, Emmanuel; Kostopanagiotou, Georgia; Smyrniotis, Vassilios; Arkadopoulos, Nikolaos

    2012-01-01

    Introduction. Pancreatic injury can manifest after major hepatectomy under vascular control. The main mechanism involved seems to be remote oxidative injury due to “spillage” of reactive oxygen species and cytokines from the liver. The aim of this study is to evaluate the role of desferrioxamine in the prevention of pancreatic injury following major hepatectomy. Methods. Twelve Landrace pigs were subjected to a combination of major hepatectomy (70–75%), using the Pringle maneuver for 150 minutes, after constructing a porta-caval side-to-side anastomosis. The duration of reperfusion was 24 hours. Animals were randomly divided into a control group (n = 6) and a desferrioxamine group (DFX, n = 6). DFX animals were treated with continuous IV infusion of desferrioxamine 100 mg/kg. Pancreatic tissue injury, c-peptide and amylase concentrations, and pancreatic tissue oxidative markers were evaluated. Results. Desferrioxamine-treated animals showed decreased c-peptide levels, decreased acinar cell necrosis, and decreased tissue malondialdehyde levels 24 hours after reperfusion compared with the control group. There was no difference in portal pressure or serum amylase levels between the groups. Conclusions. Desferrioxamine seems to attenuate pancreatic injury after major hepatectomy under vascular control possibly by preventing and reversing production and circulation of oxidative products. PMID:22791933

  9. Portal triad clamping or hepatic vascular exclusion for major liver resection. A controlled study.

    PubMed Central

    Belghiti, J; Noun, R; Zante, E; Ballet, T; Sauvanet, A

    1996-01-01

    OBJECTIVE: The authors compared operative course of patients undergoing major liver resections under portal triad clamping (PTC) or under hepatic vascular exclusion (HVE). SUMMARY BACKGROUND DATA: Reduced blood loss during liver resection is achieved by PTC or HVE. Specific complications and postoperative hepatocellular injury mediated with two procedures have not been compared. METHODS: Fifty-two noncirrhotic patients undergoing major liver resections were included in a prospective randomized study comparing both the intraoperative and postoperative courses under PTC (n = 24) or under HVE (n = 28). RESULTS: The two groups were similar at entry, but eight patients were crossed over to the other group during resection. In the HVE group, hemodynamic intolerance occurred in four (14%) patients. In the PTC group, pedicular clamping was not efficient in four patients, including three with involvement of the cavohepatic intersection and one with persistent bleeding due to tricuspid insufficiency. Intraoperative blood losses and postoperative enzyme level reflecting hepatocellular injury were similar in the two groups. Mean operative duration and mean clampage duration were significantly increased after HVE. Postoperative abdominal collections and pulmonary complications were 2.5-fold higher after HVE but without statistical significance, whereas the mean length of postoperative hospital stay was longer after HVE. CONCLUSIONS: This study shows that both methods of vascular occlusion are equally effective in reducing blood loss in major liver resections. The HVE is associated with unpredictable hemodynamic intolerance, increased postoperative complications with a longer hospital stay, and should be restricted to lesions involving the cavo-hepatic intersection. PMID:8757378

  10. Care, control, or both? Characterizing major dimensions of the mandated treatment relationship.

    PubMed

    Manchak, Sarah M; Skeem, Jennifer L; Rook, Karen S

    2014-02-01

    Current conceptualizations of the therapeutic alliance may not capture key features of therapeutic relationships in mandated treatment, which may extend beyond care (i.e., bond and affiliation) to include control (i.e., behavioral monitoring and influence). This study is designed to determine whether mandated treatment relationships involve greater control than traditional treatment relationships, and if so, whether this control covaries with reduced affiliation. In this study, 125 mental health court participants described the nature of their mandated treatment relationships using the INTREX (Benjamin, L., 2000, SASB/INTREX: Instructions for administering questionnaires, interpreting reports, and giving raters feedback (Unpublished manual). Salt Lake City, UT: University of Utah, Department of Psychology), a measure based on the interpersonal circumplex theory and assesses eight interpersonal clusters organized by orthogonal axes of affiliation and control. INTREX cluster scores were statistically compared to existing data from three separate voluntary treatment samples, and structural summary analyses were applied to distill the predominant theme of mandated treatment relationships. Compared with voluntary treatment relationships, mandated treatment relationships demonstrate greater therapist control and corresponding client submission. Nonetheless, the predominant theme of these relationships is affiliative and autonomy-granting. Although mandated treatment relationships involve significantly greater therapist control than traditional relationships, they remain largely affiliative and consistent with the principles of healthy adult attachment.

  11. A vision-based end-point control for a two-link flexible manipulator. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Obergfell, Klaus

    1991-01-01

    The measurement and control of the end-effector position of a large two-link flexible manipulator are investigated. The system implementation is described and an initial algorithm for static end-point positioning is discussed. Most existing robots are controlled through independent joint controllers, while the end-effector position is estimated from the joint positions using a kinematic relation. End-point position feedback can be used to compensate for uncertainty and structural deflections. Such feedback is especially important for flexible robots. Computer vision is utilized to obtain end-point position measurements. A look-and-move control structure alleviates the disadvantages of the slow and variable computer vision sampling frequency. This control structure consists of an inner joint-based loop and an outer vision-based loop. A static positioning algorithm was implemented and experimentally verified. This algorithm utilizes the manipulator Jacobian to transform a tip position error to a joint error. The joint error is then used to give a new reference input to the joint controller. The convergence of the algorithm is demonstrated experimentally under payload variation. A Landmark Tracking System (Dickerson, et al 1990) is used for vision-based end-point measurements. This system was modified and tested. A real-time control system was implemented on a PC and interfaced with the vision system and the robot.

  12. The dosimetric impact of control point spacing for sliding gap MLC fields.

    PubMed

    Zwan, Benjamin J; Hindmarsh, Jonathan; Seymour, Erin; Kandasamy, Kankean; Sloan, Kirbie; David, Rajesakar; Lee, Christopher

    2016-11-08

    Dynamic sliding gap multileaf collimator (MLC) fields are used to model MLC properties within the treatment planning system (TPS) for dynamic treatments. One of the key MLC properties in the Eclipse TPS is the dosimetric leaf gap (DLG) and precise determination of this parameter is paramount to ensuring accurate dose delivery. In this investigation, we report on how the spacing between control points (CPs) for sliding gap fields impacts the dose delivery, MLC positioning accuracy, and measurement of the DLG. The central axis dose was measured for sliding gap MLC fields with gap widths ranging from 2 to 40 mm. It was found that for deliveries containing two CPs, the central axis dose was underestimated by the TPS for all gap widths, with the maximum difference being 8% for a 2 mm gap field. For the same sliding gap fields containing 50 CPs, the measured dose was always within ± 2% of the TPS dose. By directly measuring the MLC trajectories we show that this dose difference is due to a systematic MLC gap error for fields containing two CPs, and that the cause of this error is due to the leaf position offset table which is incorrectly applied when the spacing between CPs is too large. This MLC gap error resulted in an increase in the measured DLG of 0.5 mm for both 6MV and 10 MV, when using fields with 2 CPs compared to 50 CPs. Furthermore, this change in DLG was shown to decrease the mean TPS-calculated dose to the target volume by 2.6% for a clinical IMRT test plan. This work has shown that systematic MLC positioning errors occur for sliding gap MLC fields containing two CPs and that using these fields to model critical TPS parameters, such as the DLG, may result in clinically significant systematic dose calculation errors during subsequent dynamic MLC treatments.

  13. The dosimetric impact of control point spacing for sliding gap MLC fields.

    PubMed

    Zwan, Benjamin J; Hindmarsh, Jonathan; Seymour, Erin; Kandasamy, Kankean; Sloan, Kirbie; David, Rajesakar; Lee, Christopher

    2016-11-01

    Dynamic sliding gap multileaf collimator (MLC) fields are used to model MLC properties within the treatment planning system (TPS) for dynamic treatments. One of the key MLC properties in the Eclipse TPS is the dosimetric leaf gap (DLG) and precise determination of this parameter is paramount to ensuring accurate dose delivery. In this investigation, we report on how the spacing between control points (CPs) for sliding gap fields impacts the dose delivery, MLC positioning accuracy, and measurement of the DLG. The central axis dose was measured for sliding gap MLC fields with gap widths ranging from 2 to 40 mm. It was found that for deliveries containing two CPs, the central axis dose was underestimated by the TPS for all gap widths, with the maximum difference being 8% for a 2 mm gap field. For the same sliding gap fields containing 50 CPs, the measured dose was always within ±2% of the TPS dose. By directly measuring the MLC trajectories we show that this dose difference is due to a systematic MLC gap error for fields containing two CPs, and that the cause of this error is due to the leaf position offset table which is incorrectly applied when the spacing between CPs is too large. This MLC gap error resulted in an increase in the measured DLG of 0.5 mm for both 6 MV and 10 MV, when using fields with 2 CPs compared to 50 CPs. Furthermore, this change in DLG was shown to decrease the mean TPS-calculated dose to the target volume by 2.6% for a clinical IMRT test plan. This work has shown that systematic MLC positioning errors occur for sliding gap MLC fields containing two CPs and that using these fields to model critical TPS parameters, such as the DLG, may result in clinically significant systematic dose calculation errors during subsequent dynamic MLC treatments. PACS number(s): 87.56.nk.

  14. Glutamine synthetase in the phloem plays a major role in controlling proline production

    PubMed Central

    Brugiere, N; Dubois, F; Limami, AM; Lelandais, M; Roux, Y; Sangwan, RS; Hirel, B

    1999-01-01

    To inhibit expression specifically in the phloem, a 274-bp fragment of a cDNA (Gln1-5) encoding cytosolic glutamine synthetase (GS1) from tobacco was placed in the antisense orientation downstream of the cytosolic Cu/Zn superoxide dismutase promoter of Nicotiana plumbaginifolia. After Agrobacterium-mediated transformation, two transgenic N. tabacum lines exhibiting reduced levels of GS1 mRNA and GS activity in midribs, stems, and roots were obtained. Immunogold labeling experiments allowed us to verify that the GS protein content was markedly decreased in the phloem companion cells of transformed plants. Moreover, a general decrease in proline content in the transgenic plants in comparison with wild-type tobacco was observed when plants were forced to assimilate large amounts of ammonium. In contrast, no major changes in the concentration of amino acids used for nitrogen transport were apparent. A (15)NH(4)(+)-labeling kinetic over a 48-hr period confirmed that in leaves of transgenic plants, the decrease in proline production was directly related to glutamine availability. After 2 weeks of salt treatment, the transgenic plants had a pronounced stress phenotype, consisting of wilting and bleaching in the older leaves. We conclude that GS in the phloem plays a major role in regulating proline production consistent with the function of proline as a nitrogen source and as a key metabolite synthesized in response to water stress. PMID:10521528

  15. On the Relationship between Locus of Control and the Grade Point Average of the Iranian Azad University EFL Students

    ERIC Educational Resources Information Center

    Bozorgi, Simin

    2009-01-01

    The present study sponsored by Islamic Azad University of Bandar Abbas, Iran, intended to see if locus of control really affected students' language achievement. It was hypothesized that subjects' loci of controls affected their GPA's in meaningful and significant ways. The study also tried to measure the effects of students' major and their…

  16. Points of View: Content versus Process--Is This a Fair Choice? Can Nonmajors Courses Lead to Biological Literacy? Do Majors Courses Do Any Better?

    ERIC Educational Resources Information Center

    Klymkowsky, Michael W.

    2005-01-01

    "Points of View" addresses issues faced by many people within the life sciences educational realm. This issue addresses the question "What should a biology student know?" There has been a long, evolving, and often politically charged debate as to what the nonmajor student should know about science. In order to establish a basis…

  17. Percutaneous transhepatic sphincterotomy of the major papilla and stone extraction without endoscopic control

    SciTech Connect

    Angelini, Giampaolo; Mansueto, Giancarlo; Giacomin, Davide; Casarini, Maria Beatrice; Garaffo, Salvatore; Biasiutti, Carlo

    1997-05-15

    Obstructive jaundice due to an impacted stone in the common bile duct (CBD) was seen in a patient who had previously undergone Billroth II gastric resection and cholecystectomy. Surgical and endoscopic approaches to the common bile duct failed owing to pericholedochal adhesions and the excessive length of the duodenal loop. The patient was therefore treated percutaneously (sphincterotomy and stone extraction) without endoscopic control.

  18. Performance of the NO{sub x} emissions advisor and advanced steam temperature control at Possum Point Station

    SciTech Connect

    Leigh, M.; Labbe, D.

    1995-10-01

    Virginia Power installed Stone and Webster`s NO{sub x} Emissions Advisor and Advanced Steam Temperature Control Systems on Possum Point Units 3 and 4 during the Spring of 1995 to achieve near-term NO{sub x} compliance objectives and improve thermal performance. The installation of the advanced control and automation systems was integrated into the existing control system using standard hardware and software. The advanced control systems operate under Windows-NT on a Pentium personal computer (PC) in a multi-process environment, exchanging data with the distributed control system (DCS) through a dedicated serial link. Testing has demonstrated NO, reductions of greater than 20 percent through the application of the NO{sub x} Emissions Advisor on these units, while maintaining steam temperatures and unit efficiency. Possum Point Power Station Units 3 and 4 are pulverized coal, tangentially fired boilers, producing 107 and 232 MW, respectively.

  19. Choosing the Optimal Number of B-spline Control Points (Part 1: Methodology and Approximation of Curves)

    NASA Astrophysics Data System (ADS)

    Harmening, Corinna; Neuner, Hans

    2016-09-01

    Due to the establishment of terrestrial laser scanner, the analysis strategies in engineering geodesy change from pointwise approaches to areal ones. These areal analysis strategies are commonly built on the modelling of the acquired point clouds. Freeform curves and surfaces like B-spline curves/surfaces are one possible approach to obtain space continuous information. A variety of parameters determines the B-spline's appearance; the B-spline's complexity is mostly determined by the number of control points. Usually, this number of control points is chosen quite arbitrarily by intuitive trial-and-error-procedures. In this paper, the Akaike Information Criterion and the Bayesian Information Criterion are investigated with regard to a justified and reproducible choice of the optimal number of control points of B-spline curves. Additionally, we develop a method which is based on the structural risk minimization of the statistical learning theory. Unlike the Akaike and the Bayesian Information Criteria this method doesn't use the number of parameters as complexity measure of the approximating functions but their Vapnik-Chervonenkis-dimension. Furthermore, it is also valid for non-linear models. Thus, the three methods differ in their target function to be minimized and consequently in their definition of optimality. The present paper will be continued by a second paper dealing with the choice of the optimal number of control points of B-spline surfaces.

  20. HDAC6 controls major cell response pathways to cytotoxic accumulation of protein aggregates

    PubMed Central

    Boyault, Cyril; Zhang, Yu; Fritah, Sabrina; Caron, Cécile; Gilquin, Benoit; Kwon, So Hee; Garrido, Carmen; Yao, Tso-Pang; Vourc’h, Claire; Matthias, Patrick; Khochbin, Saadi

    2007-01-01

    A cellular defense mechanism counteracts the deleterious effects of misfolded protein accumulation by eliciting a stress response. The cytoplasmic deacetylase HDAC6 (histone deacetylase 6) was previously shown to be a key element in this response by coordinating the clearance of protein aggregates through aggresome formation and their autophagic degradation. Here, for the first time, we demonstrate that HDAC6 is involved in another crucial cell response to the accumulation of ubiquitinated protein aggregates, and unravel its molecular basis. Indeed, our data show that HDAC6 senses ubiquitinated cellular aggregates and consequently induces the expression of major cellular chaperones by triggering the dissociation of a repressive HDAC6/HSF1 (heat-shock factor 1)/HSP90 (heat-shock protein 90) complex and a subsequent HSF1 activation. HDAC6 therefore appears as a master regulator of the cell protective response to cytotoxic protein aggregate formation. PMID:17785525

  1. NRRI summary of Florida Public Service Commission: Fraud control policies of seven major Florida utilities

    SciTech Connect

    1995-12-31

    The Florida Public Service Commission (PSC) Staff recently completed an audit of fraud control policies and programs at the State`s largest regulated electric and local telephone utilities. The purpose of the audit was to examine the ability of Florida`s largest regulated utilities to deter, detect, and resolve occurrences of fraud. The Staff audited the state`s seven largest regulated electric and local telephone utilities: Florida Power Corporation, Florida Power and Light, Gulf Power Corporation, Tampa Electric Company, GTE-Florida, BellSouth Telecommunications (Southern Bell), and Sprint United/Centel. The audit scope was limited to fraudulent acts committed by employees, contractors, suppliers, or agents of the seven utilities. Information regarding the utilities` fraud control policies and programs was obtained through surveys, document requests, and interviews with managers and officers.

  2. Can Coffee Chemical Compounds and Insecticidal Plants Be Harnessed for Control of Major Coffee Pests?

    PubMed

    Green, Paul W C; Davis, Aaron P; Cossé, Allard A; Vega, Fernando E

    2015-11-04

    Pests and pathogens threaten coffee production worldwide and are difficult to control using conventional methods, such as insecticides. We review the literature on the chemistry of coffee, concentrating on compounds most commonly reported from Coffea arabica and Coffea canephora. Differences in chemistry can distinguish coffee species and varieties, and plants grown under different biogeographic conditions exhibit different chemotypes. A number of chemical groups, such as alkaloids and caffeoylquinic acids, are known to be insecticidal, but most studies have investigated their effects on coffee quality and flavor. More research is required to bridge this gap in knowledge, so that coffee can be bred to be more resistant to pests. Furthermore, we report on some pesticidal plants that have been used for control of coffee pests. Locally sourced pesticidal plants have been underutilized and offer a sustainable alternative to conventional insecticides and could be used to augment breeding for resilience of coffee plants.

  3. Maximum Entropy/Optimal Projection (MEOP) control design synthesis: Optimal quantification of the major design tradeoffs

    NASA Technical Reports Server (NTRS)

    Hyland, D. C.; Bernstein, D. S.

    1987-01-01

    The underlying philosophy and motivation of the optimal projection/maximum entropy (OP/ME) stochastic modeling and reduced control design methodology for high order systems with parameter uncertainties are discussed. The OP/ME design equations for reduced-order dynamic compensation including the effect of parameter uncertainties are reviewed. The application of the methodology to several Large Space Structures (LSS) problems of representative complexity is illustrated.

  4. Integrated quality control: implementation and validation of instrument function checks and procedural controls for a cartridge-based point-of-care system for critical care analysis.

    PubMed

    D'Orazio, Paul; Mansouri, Sohrab

    2013-03-01

    In this article, the process used to develop and validate an integrated quality-control system for a cartridge-based, point-of-care system for critical care analysis is outlined. Application of risk management principles has resulted in a quality control system using a combination of statistical quality control with onboard reference solutions and failure pattern recognition used to flag common failure modes during the analytical phase of the testing process. A combination of traditional external quality control, integrated quality control to monitor ongoing instrument functionality, operator training, and other laboratory-implemented monitors is most effective in controlling known failure modes during the testing process.

  5. Choosing the optimal number of B-spline control points (Part 2: Approximation of surfaces and applications)

    NASA Astrophysics Data System (ADS)

    Harmening, Corinna; Neuner, Hans

    2017-03-01

    Freeform surfaces like B-splines have proven to be a suitable tool to model laser scanner point clouds and to form the basis for an areal data analysis, for example an areal deformation analysis. A variety of parameters determine the B-spline's appearance, the B-spline's complexity being mostly determined by the number of control points. Usually, this parameter type is chosen by intuitive trial-and-error-procedures. In [10] the problem of finding an alternative to these trial-and-error-procedures was addressed for the case of B-spline curves: The task of choosing the optimal number of control points was interpreted as a model selection problem. Two model selection criteria, the Akaike and the Bayesian Information Criterion, were used to identify the B-spline curve with the optimal number of control points from a set of candidate B-spline models. In order to overcome the drawbacks of the information criteria, an alternative approach based on statistical learning theory was developed. The criteria were evaluated by means of simulated data sets. The present paper continues these investigations. If necessary, the methods proposed in [10] are extended to areal approaches so that they can be used to determine the optimal number of B-spline surface control points. Furthermore, the methods are evaluated by means of real laser scanner data sets rather than by simulated ones. The application of those methods to B-spline surfaces reveals the datum problem of those surfaces, meaning that location and number of control points of two B-splines surfaces are only comparable if they are based on the same parameterization. First investigations to solve this problem are presented.

  6. Efficacy and safety of curcumin in major depressive disorder: a randomized controlled trial.

    PubMed

    Sanmukhani, Jayesh; Satodia, Vimal; Trivedi, Jaladhi; Patel, Tejas; Tiwari, Deepak; Panchal, Bharat; Goel, Ajay; Tripathi, Chandra Bhanu

    2014-04-01

    Curcumin, an active ingredient of Curcuma longa Linn (Zingiberaceae), has shown potential antidepressant-like activity in animal studies. The objectives of this trial were to compare the efficacy and safety of curcumin with fluoxetine in patients with major depressive disorder (MDD). Herein, 60 patients diagnosed with MDD were randomized in a 1:1:1 ratio for six weeks observer-masked treatment with fluoxetine (20 mg) and curcumin (1000 mg) individually or their combination. The primary efficacy variable was response rates according to Hamilton Depression Rating Scale, 17-item version (HAM-D17 ). The secondary efficacy variable was the mean change in HAM-D17 score after six weeks. We observed that curcumin was well tolerated by all the patients. The proportion of responders as measured by the HAM-D17 scale was higher in the combination group (77.8%) than in the fluoxetine (64.7%) and the curcumin (62.5%) groups; however, these data were not statistically significant (P = 0.58). Interestingly, the mean change in HAM-D17 score at the end of six weeks was comparable in all three groups (P = 0.77). This study provides first clinical evidence that curcumin may be used as an effective and safe modality for treatment in patients with MDD without concurrent suicidal ideation or other psychotic disorders. .

  7. Doping control analysis for adrafinil and its major metabolites in human urine.

    PubMed

    Lu, Jianghai; Wang, Xiaobing; Yang, Shuming; Liu, Xin; Qin, Yang; Shen, Li; Wu, Yun; Xu, Youxuan; Wu, Moutian; Ouyang, Gangfeng

    2009-06-01

    A new and reliable two-step liquid chromatography/tandem mass spectrometry (LC/MS/MS) method in combination with gas chromatography/mass spectrometry (GC/MS) for the screening and confirmation of adrafinil and its major metabolites, modafinil and modafinil acid, in human urine has been developed and validated. The method involved reversed-phase C18 solid-phase extraction (SPE) cartridge extraction and MS analysis by means of LC/MS/MS and GC/MS. The study illustrated that the ESI capillary temperature played a key role in the formation of the protonated molecule. The limits of detection (LODs) of the developed method for the three compounds were lower than the minimum required performance limit (MRPL) of the World Anti-Doping Agency (WADA). The human urine samples obtained after the oral administration of modafinil and from the Beijing 2008 Olympic Games were analyzed by using the described method, which has also been successfully applied to routine analyses and the WADA Proficiency Test.

  8. Mutational analysis of the major coat protein of M13 identifies residues that control protein display.

    PubMed Central

    Weiss, G. A.; Wells, J. A.; Sidhu, S. S.

    2000-01-01

    We have reported variants of the M13 bacteriophage major coat protein (P8) that enable high copy display of monomeric and oligomeric proteins, such as human growth hormone and steptavidin, on the surface of phage particles (Sidhu SS, Weiss GA, Wells JA. 2000. High copy display of large proteins on phage for functional selections. J Mol Biol 296:487-495). Here, we explore how an optimized P8 variant (opti-P8) could evolve the ability to efficiently display a protein fused to its N-terminus. Reversion of individual opti-P8 residues back to the wild-type P8 residue identifies a limited set of hydrophobic residues responsible for the high copy protein display. These hydrophobic amino acids bracket a conserved hydrophobic face on the P8 alpha helix thought to be in contact with the phage coat. Mutations additively combine to promote high copy protein display, which was further enhanced by optimization of the linker between the phage coat and the fusion protein. These data are consistent with a model in which protein display-enhancing mutations allow for better packing of the fusion protein into the phage coat. The high tolerance for phage coat protein mutations observed here suggests that filamentous phage coat proteins could readily evolve new capabilities. PMID:10794407

  9. Application of hazard analysis and critical control point methodology and risk-based grading to consumer food safety surveys.

    PubMed

    Røssvoll, Elin Halbach; Ueland, Øydis; Hagtvedt, Therese; Jacobsen, Eivind; Lavik, Randi; Langsrud, Solveig

    2012-09-01

    Traditionally, consumer food safety survey responses have been classified as either "right" or "wrong" and food handling practices that are associated with high risk of infection have been treated in the same way as practices with lower risks. In this study, a risk-based method for consumer food safety surveys has been developed, and HACCP (hazard analysis and critical control point) methodology was used for selecting relevant questions. We conducted a nationally representative Web-based survey (n = 2,008), and to fit the self-reported answers we adjusted a risk-based grading system originally developed for observational studies. The results of the survey were analyzed both with the traditional "right" and "wrong" classification and with the risk-based grading system. The results using the two methods were very different. Only 5 of the 10 most frequent food handling violations were among the 10 practices associated with the highest risk. These 10 practices dealt with different aspects of heat treatment (lacking or insufficient), whereas the majority of the most frequent violations involved storing food at room temperature for too long. Use of the risk-based grading system for survey responses gave a more realistic picture of risks associated with domestic food handling practices. The method highlighted important violations and minor errors, which are performed by most people and are not associated with significant risk. Surveys built on a HACCP-based approach with risk-based grading will contribute to a better understanding of domestic food handling practices and will be of great value for targeted information and educational activities.

  10. Locus control region HS2 point mutations are generally not responsible for elevated fetal hemoglobin expression of sickle cell patients

    SciTech Connect

    Gilman, J.G.

    1994-09-01

    The locus control region (LCR), composed of four hypersensitive sites (HS1-4) 5{prime} of the {epsilon} globin gene, confers strong, copy-number dependent expression on globin genes in transgenic mice. Several {beta}-globin gene cluster haplotypes carry the sickle cell gene, and show variable levels of fetal hemoglobin (Hb F) expression in association with DNA sequence differences in HS2, {gamma} and {beta} globin promoters, and {gamma}IVSII: The Senegal (SEN or No. 3) haplotype generally has high (>10%) Hb F, Benin (BEN or No. 19) has intermediate Hb F (but some low and some high), and Banu (BAN or No. 20) generally has low Hb F. Huisman and colleagues have proposed that `factors produced under conditions of hematopoietic stress, together with genetic determinants on the haplotype-3 like LCR sequences, allow for high level expression of {gamma} globin genes`. We have now used slot blot to screen high Hb F (>9.5%) and low Hb F cases for two of the three HS2 point mutations described by Oener et al. Comparing eight high Hb F BEN/BEN with two low Hb F BEN/BEN, all ten had the BEN mutations considered by Oener et al. to be associated with low Hb F. Comparing three high Hb F BEN/BAN with two low Hb F BEN/BAN, all five were heterozygous at three positions; this is consistent with BEN having G and T and BAN having A at both positions. DNA sequencing of HS2 for BAN, which is generally associated with low HB F, showed that the point mutations at all three positions were those seen in SEN (generally high Hb F); only the AT repeat region showed major differences, confirming results of Huisman and colleagues. Hence, if there is any effect of HS2 of the Senegal sickle cell haplotype in causing elevated Hb F under hematopoietic stress, it must be due to specific variation in the AT repeat region, which Oener et al. have suggested may bind a silencer.

  11. Fractures, not Plumes, Have Controlled Major Seamount Volcanism in the Pacific over 170 Million Years

    NASA Astrophysics Data System (ADS)

    Natland, J. H.; Winterer, E. L.

    2003-12-01

    The distribution of guyots and atolls and large volcanic islands on the Pacific plate can be used to outline the likely connection between stresses acting on the plate and the gradual development of large, linear volcanic chains over the past 170 Ma. We construe three general periods with different stress regimes in the history of the Pacific plate. 1) During the Jurassic and Early Cretaceous, the Pacific plate was surrounded by ridge segments and there were no major stress alignments within it. Within-plate volcanism thus assumed the scattered arrangement for the condition of no tectonic stress (1), and the large Magellan and Wake seamount clusters formed. Near the eastern boundaries of the plate, complex and shifting patterns of ridge reorganization dictated formation of very long, splayed, near-axis ridges such as Horizon Guyot and Necker Ridge. 2) At about 90 Ma, the growing middle-aged Pacific plate achieved its first persistent stress regime with the formation of subduction boundaries along its western or northwestern margin. The plate was no longer static but began to move over the asthenosphere and into the mantle. Subduction boundaries and the overall direction of subduction are uncertain, but this imparted a general yet not fully stable component of tension across the plate, producing the NNW Gilbert-Marshall, Line and Emperor Seamount ridges, generally orthogonal to the overall direction of least principal stress. The Line Island seamount chain, being near ridge axes, sustained a variable stress regime. It thus has no age progression of rocks dated between 70-90 Ma (2), great width, and a dual orientations of ridges. 3) By 47 Ma, nearly half of the boundaries of the Pacific plate now were trenches spanning from the Aleutians to New Zealand. In addition, northward migration of the Indian plate and Australia caught a major portion of the westerly moving Pacific plate between the northeast corner of the Tonga Trench and the Aleutians. The plate could not

  12. Ii Chain Controls the Transport of Major Histocompatibility Complex Class II Molecules to and from Lysosomes

    PubMed Central

    Brachet, Valérie; Raposo, Graça; Amigorena, Sebastian; Mellman, Ira

    1997-01-01

    Major histocompatibility complex class II molecules are synthesized as a nonameric complex consisting of three αβ dimers associated with a trimer of invariant (Ii) chains. After exiting the TGN, a targeting signal in the Ii chain cytoplasmic domain directs the complex to endosomes where Ii chain is proteolytically processed and removed, allowing class II molecules to bind antigenic peptides before reaching the cell surface. Ii chain dissociation and peptide binding are thought to occur in one or more postendosomal sites related either to endosomes (designated CIIV) or to lysosomes (designated MIIC). We now find that in addition to initially targeting αβ dimers to endosomes, Ii chain regulates the subsequent transport of class II molecules. Under normal conditions, murine A20 B cells transport all of their newly synthesized class II I-Ab αβ dimers to the plasma membrane with little if any reaching lysosomal compartments. Inhibition of Ii processing by the cysteine/serine protease inhibitor leupeptin, however, blocked transport to the cell surface and caused a dramatic but selective accumulation of I-Ab class II molecules in lysosomes. In leupeptin, I-Ab dimers formed stable complexes with a 10-kD NH2-terminal Ii chain fragment (Ii-p10), normally a transient intermediate in Ii chain processing. Upon removal of leupeptin, Ii-p10 was degraded and released, I-Ab dimers bound antigenic peptides, and the peptide-loaded dimers were transported slowly from lysosomes to the plasma membrane. Our results suggest that alterations in the rate or efficiency of Ii chain processing can alter the postendosomal sorting of class II molecules, resulting in the increased accumulation of αβ dimers in lysosome-like MIIC. Thus, simple differences in Ii chain processing may account for the highly variable amounts of class II found in lysosomal compartments of different cell types or at different developmental stages. PMID:9105036

  13. Major neurotransmitter systems in dorsal hippocampus and basolateral amygdala control social recognition memory

    PubMed Central

    Garrido Zinn, Carolina; Clairis, Nicolas; Silva Cavalcante, Lorena Evelyn; Furini, Cristiane Regina Guerino; de Carvalho Myskiw, Jociane; Izquierdo, Ivan

    2016-01-01

    Social recognition memory (SRM) is crucial for reproduction, forming social groups, and species survival. Despite its importance, SRM is still relatively little studied. Here we examine the participation of the CA1 region of the dorsal hippocampus (CA1) and the basolateral amygdala (BLA) and that of dopaminergic, noradrenergic, and histaminergic systems in both structures in the consolidation of SRM. Male Wistar rats received intra-CA1 or intra-BLA infusions of different drugs immediately after the sample phase of a social discrimination task and 24-h later were subjected to a 5-min retention test. Animals treated with the protein synthesis inhibitor, anisomycin, into either the CA1 or BLA were unable to recognize the previously exposed juvenile (familiar) during the retention test. When infused into the CA1, the β-adrenoreceptor agonist, isoproterenol, the D1/D5 dopaminergic receptor antagonist, SCH23390, and the H2 histaminergic receptor antagonist, ranitidine, also hindered the recognition of the familiar juvenile 24-h later. The latter drug effects were more intense in the CA1 than in the BLA. When infused into the BLA, the β-adrenoreceptor antagonist, timolol, the D1/D5 dopamine receptor agonist, SKF38393, and the H2 histaminergic receptor agonist, ranitidine, also hindered recognition of the familiar juvenile 24-h later. In all cases, the impairment to recognize the familiar juvenile was abolished by the coinfusion of agonist plus antagonist. Clearly, both the CA1 and BLA, probably in that order, play major roles in the consolidation of SRM, but these roles are different in each structure vis-à-vis the involvement of the β-noradrenergic, D1/D5-dopaminergic, and H2-histaminergic receptors therein. PMID:27482097

  14. Air quality control in the ART laboratory is a major determinant of IVF success

    PubMed Central

    Esteves, Sandro C; Bento, Fabiola C

    2016-01-01

    A recently published article described how a fertility center in the United States implemented air quality control to newly designed in vitro fertilization (IVF) laboratory.1 A highly-efficient air filtration was achieved by installing a centered system supplying filtered air to the IVF laboratory and related critical areas, combining air particulate and volatile organic compound (VOC) filtration. As a consequence, live birth rates were increased by improvements in air quality. This article highlights the key aspects of air contamination in the IVF context. The topic is important not only to IVF specialists but also to Andrologists due to the great number of male infertility patients referred to assisted reproductive technology (ART) treatments. The evidence is growing that laboratory air quality is paramount importance for improved IVF outcome. PMID:26585700

  15. Using Mutual Information to capture Major Concerns of Postural Control in a Tossing activity

    PubMed Central

    Gazula, Harshvardhan; Chang, Chien Chi; Lu, Ming-Lun; Hsiang, Simon M.

    2015-01-01

    Human body motion for load-tossing activity was partitioned into three phases using four critical events based on the load position viz. lift-off, closest to body, peak and release. For each phase, three objective functions values, viz. mobilization, stabilization and muscular torque utilization, used to control the motion patterns, were then calculated. We hypothesize that the relationships between different objective functions can be extracted using information theory. The kinematic data obtained with 36 treatment combinations (2 tossing distances, 2 tossing heights, 3 weights, and 3 target clearances) was used to estimate the mutual information between each pair of objective functions and construct Chow-Liu trees. Results from this research indicate that there was no dominant concern in the first two phases of the activity; however, torque utilization and mobilization were found to be important factors in the third phase of the load tossing activity. PMID:25680297

  16. On the Transfer and Control of Space Probes Around the L1 Point of the Sun-Earth+Moon System

    NASA Astrophysics Data System (ADS)

    Hou, Xi-Yun; Liu, Lin

    2008-01-01

    The motion around the collinear libration points in the restricted three body problem is unstable. But there exist conditionally stable periodic orbits around these points. Special-purpose space probes located in the vicinity of these points (e.g., ISEE-3, SOHO) can benefit from this dynamical property, in regard to maintaining the orbit in position and the energy required of placing the probe in position. As an example, we study in this paper the launch and orbital control of a space probe around the L1 libration point in the system consisting of the Sun and the Earth-Moon. We present some theoretical and numerical simulations' results, which may serve as a basis for the realization of such a space probe in future.

  17. Biological control of major postharvest pathogens on apple with Candida sake.

    PubMed

    Viñas, I; Usall, J; Teixidó, N; Sanchis, V

    1998-03-03

    Epiphytic microorganisms isolated from apples, pears and the surfaces of apple leaves were screened for antagonistic activity against Penicillium expansum (blue-mold), Botrytis cinerea (gray-mold) and Rhizopus nigricans (Rhizopus rot) on apple (Malus domestica). A total of 933 bacteria and yeasts were tested in primary screening against P. expansum. Ninety-two strains reduced the lesion size on apples by more than 50%, 72 of which were isolated from the surface of apples. For secondary screening against P. expansum, B. cinerea and R. nigricans, 31 strains were selected. The most promising isolate, CPA-1, was identified as Candida sake. This yeast, isolated from apples in storage season was very effective against all three diseases. Wounded Golden Delicious apples protected with the yeast suspension at a concentration of 2.6 x 10(6) CFU/ml and inoculated with conidia of B. cinerea and R. nigricans of 10(5) and 10(4) conidia/ml, respectively, did not develop rot. Complete control of P. expansum was obtained at the same concentration of the antagonist with a pathogen inoculum concentration of 10(3) conidia/ml. This strain, also provided excellent control of rot development under cold storage conditions. The strain of Candida sake can grow actively in aerobic conditions. In drop-inoculated wounds of apples, the populations of C. sake increased by more than 50-fold during the first 24 h at 20 degrees C. The maximum population of C. sake on apple wounds was the same at 20 as at 1 degrees C and was recovered after three and twenty days, respectively.

  18. In-stream attenuation of nitrogen and phosphorus from major point source in large-scale watershed: mixed source and long-term variation

    NASA Astrophysics Data System (ADS)

    Chen, X.; Fulda, M.; Keller, A. A.

    2011-12-01

    Increased human activity in agriculture and industry has posed significant impact on natural water bodies and resulted in water quality deterioration. Agricultural non-point source pollution and urban point source discharge from municipal waste water treatment plant are the more recent concerns. Computer models are often used to help assess the fate and transport of pollutant, which involves complex interactions such as adsorption, biochemical reaction and plants uptake. However, it remains to be a challenge to assess the attenuation of total nitrogen and total phosphorus in large-scale watershed where there are significant difference in land use types and soil properties, especially when there are significant temporal variations through a long-term simulation. In this study, a large-scale watershed model in the Ohio River Basin was constructed considering a ten year simulation period. To assess the downstream impacts of increasing or decreasing nutrient loads, a hypothetical waste water treatment plant was added as the point source in different subwatersheds, monitoring the downstream effects. Five scenarios (100 kg/d Ammonia, 100 kg/d Nitrate, 100 kg/d Phosphate, mixed 100 kg/d Ammonia & 100 kg/d Phosphate and mixed 100 kg/d Nitrate & 100 kg/d Phosphate) were examined to assess the attenuation process throughout the 10-years simulation. In addition to significant differences in the attenuation in different subwatersheds, the various loads had complex interrelations. We also observed significant variations in attenuation for short-term simulation, while in long-term, the attenuation factors tended to be stabilized.

  19. Spacecraft stability, dynamics and control near the triangular Lagrange points influenced by multiple Trojan asteroids

    NASA Astrophysics Data System (ADS)

    Trivailo, Olga

    2007-04-01

    In view of the importance of Lagrange points to the exploration and development of space, the dynamics and stability of a satellite were studied under multiple Trojan asteroids influence. Through the use of a numerical simulator developed in MATLAB, consideration was given to the effects of gravitational forces exerted by the asteroids themselves, simulating the resulting insignificant influence of the Trojan asteroids on a satellite placed at the triangular Lagrange points. The study of optimized satellite transfers between triangular Lagrange points allowed the enforcement of multiple, specific, non-linear constraints on critical mission parameters of maximum thrust, mission duration, propellant consumption and accelerations. The optimized transfer trajectory between the two triangular Lagrange points was direction sensitive. That is, the minimum thrust optimized transfer trajectory for a satellite from L4 to L5 was unique and vastly different to that from L5 to L4. A further exciting discovery highlighted that superposition of the latter trajectories formed a perfectly smooth, uninterrupted kidney-shaped loop, fused at the two relevant points of connection. Implications for this phenomenon extend directly to future mission planning.

  20. Angle-of-Attack-Modulated Terminal Point Control for Neptune Aerocapture

    NASA Technical Reports Server (NTRS)

    Queen, Eric M.

    2004-01-01

    An aerocapture guidance algorithm based on a calculus of variations approach is developed, using angle of attack as the primary control variable. Bank angle is used as a secondary control to alleviate angle of attack extremes and to control inclination. The guidance equations are derived in detail. The controller has very small onboard computational requirements and is robust to atmospheric and aerodynamic dispersions. The algorithm is applied to aerocapture at Neptune. Three versions of the controller are considered with varying angle of attack authority. The three versions of the controller are evaluated using Monte Carlo simulations with expected dispersions.

  1. Recommendations for dealing with waste contaminated with Ebola virus: a Hazard Analysis of Critical Control Points approach

    PubMed Central

    Edmunds, Kelly L; Elrahman, Samira Abd; Bell, Diana J; Brainard, Julii; Dervisevic, Samir; Fedha, Tsimbiri P; Few, Roger; Howard, Guy; Lake, Iain; Maes, Peter; Matofari, Joseph; Minnigh, Harvey; Mohamedani, Ahmed A; Montgomery, Maggie; Morter, Sarah; Muchiri, Edward; Mudau, Lutendo S; Mutua, Benedict M; Ndambuki, Julius M; Pond, Katherine; Sobsey, Mark D; van der Es, Mike; Zeitoun, Mark

    2016-01-01

    Abstract Objective To assess, within communities experiencing Ebola virus outbreaks, the risks associated with the disposal of human waste and to generate recommendations for mitigating such risks. Methods A team with expertise in the Hazard Analysis of Critical Control Points framework identified waste products from the care of individuals with Ebola virus disease and constructed, tested and confirmed flow diagrams showing the creation of such products. After listing potential hazards associated with each step in each flow diagram, the team conducted a hazard analysis, determined critical control points and made recommendations to mitigate the transmission risks at each control point. Findings The collection, transportation, cleaning and shared use of blood-soiled fomites and the shared use of latrines contaminated with blood or bloodied faeces appeared to be associated with particularly high levels of risk of Ebola virus transmission. More moderate levels of risk were associated with the collection and transportation of material contaminated with bodily fluids other than blood, shared use of latrines soiled with such fluids, the cleaning and shared use of fomites soiled with such fluids, and the contamination of the environment during the collection and transportation of blood-contaminated waste. Conclusion The risk of the waste-related transmission of Ebola virus could be reduced by the use of full personal protective equipment, appropriate hand hygiene and an appropriate disinfectant after careful cleaning. Use of the Hazard Analysis of Critical Control Points framework could facilitate rapid responses to outbreaks of emerging infectious disease. PMID:27274594

  2. Adaptive backstepping control for three axis microsatellite attitude pointing under actuator faults

    NASA Astrophysics Data System (ADS)

    MOHAMMED, M. A. SI; BOUSSADIA, H.; BELLAR, A.; ADNANE, A.

    2017-01-01

    This paper presents the design of Low Earth Orbit (LEO) micro-satellite attitude controller using reaction wheels, and under actuator faults. Firstly, a backstepping controller is developed when the actuator is fault-free. Then, a fault tolerant controller is designed to compensate the actuator fault. Two types of this latter are considered (additive and multiplicative faults). The presented control strategy is based on adaptive backstepping technique. The simulation results clearly demonstrate the effectiveness of the presented technique.

  3. Genetic control and expression of the major ejaculatory bulb protein (PEB-me) in Drosophila melanogaster.

    PubMed

    Ludwig, M Z; Uspensky, I I; Ivanov, A I; Kopantseva, M R; Dianov, C M; Tamarina, N A; Korochkin, L I

    1991-06-01

    PEB-me is a predominant protein of mature Drosophila melanogaster ejaculatory bulbs. It is resolved into four or five closely spaced subfractions (apparent molecular weight 35-39 kD) by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Four electrophoretic variants of PEB-me differing in apparent molecular weight by 200-800 daltons were found. These appear to be controlled by four alleles of a gene (peb) located by recombination and deletion mapping to the 60F1-2 region of chromosome 2. A minor ejaculatory bulb protein of ca. 80 kD (hPEB) was found to be immunochemically related to PEB and possibly encoded by peb. PEB is not detected by immunoblotting techniques in virgin females, in male tissues other than the ejaculatory bulb, or during developmental stages preceding the formation of this organ. The results of transplantations of genital imaginal discs and of immature ejaculatory bulbs between two strains having different PEB alleles suggest that the ejaculatory bulb is the site of PEB synthesis. In flies mutant for tra, tra-2, dsx, or ix, tissue specificity of PEB localization is retained and the protein is found whenever the ejaculatory bulb is formed, regardless of the chromosomal sex of the fly. The protein is transferred into the female genital duct during mating, where it can be detected for up to 12 hr. Possible functions of PEB in Drosophila reproduction are discussed.

  4. A single point in protein trafficking by Plasmodium falciparum determines the expression of major antigens on the surface of infected erythrocytes targeted by human antibodies.

    PubMed

    Chan, Jo-Anne; Howell, Katherine B; Langer, Christine; Maier, Alexander G; Hasang, Wina; Rogerson, Stephen J; Petter, Michaela; Chesson, Joanne; Stanisic, Danielle I; Duffy, Michael F; Cooke, Brian M; Siba, Peter M; Mueller, Ivo; Bull, Peter C; Marsh, Kevin; Fowkes, Freya J I; Beeson, James G

    2016-11-01

    Antibodies to blood-stage antigens of Plasmodium falciparum play a pivotal role in human immunity to malaria. During parasite development, multiple proteins are trafficked from the intracellular parasite to the surface of P. falciparum-infected erythrocytes (IEs). However, the relative importance of different proteins as targets of acquired antibodies, and key pathways involved in trafficking major antigens remain to be clearly defined. We quantified antibodies to surface antigens among children, adults, and pregnant women from different malaria-exposed regions. We quantified the importance of antigens as antibody targets using genetically engineered P. falciparum with modified surface antigen expression. Genetic deletion of the trafficking protein skeleton-binding protein-1 (SBP1), which is involved in trafficking the surface antigen PfEMP1, led to a dramatic reduction in antibody recognition of IEs and the ability of human antibodies to promote opsonic phagocytosis of IEs, a key mechanism of parasite clearance. The great majority of antibody epitopes on the IE surface were SBP1-dependent. This was demonstrated using parasite isolates with different genetic or phenotypic backgrounds, and among antibodies from children, adults, and pregnant women in different populations. Comparisons of antibody reactivity to parasite isolates with SBP1 deletion or inhibited PfEMP1 expression suggest that PfEMP1 is the dominant target of acquired human antibodies, and that other P. falciparum IE surface proteins are minor targets. These results establish SBP1 as part of a critical pathway for the trafficking of major surface antigens targeted by human immunity, and have key implications for vaccine development, and quantifying immunity in populations.

  5. Landscape controls on dissolved nutrients, organic matter and major ions in a suburbanizing watershed

    NASA Astrophysics Data System (ADS)

    Daley, M. L.; McDowell, W. H.

    2010-12-01

    Understanding the relative importance of anthropogenic and natural landscape features that drive spatial variability in water quality is a central challenge in studying the biogeochemistry of heterogeneous landscapes. We quantified the average annual flux and concentration of dissolved inorganic nitrogen (DIN), dissolved organic nitrogen (DON), dissolved organic carbon (DOC), phosphate-P (PO4-P), sodium (Na+) and chloride (Cl-) at ~40 stream sites in three major (51 to 903 km2) NH basins. We used GIS to quantify anthropogenic (e.g. human population density, % impervious surface cover and % agriculture) and natural (e.g. % forest, % wetlands and soil C:N) landscape features for each sub-basin and then employed multiple-regression analysis to relate water quality parameters to landscape characteristics. Anthropogenic features were strong predictors of DIN flux and Na+ and Cl- concentrations, whereas wetland cover (a natural feature) was a significant, but weak predictor of DOC (r2=0.26, p<0.01) and DON (r2 = 0.14, p<0.05) flux. Anthropogenic features could not explain a significant amount of variance in DON or DOC flux. Mean PO4-P concentrations were surprisingly low (<0.015 mg P/L) when compared to the larger range in mean DIN concentrations (0.03 to 0.96 mg/L) and consequently no landscape characteristics could explain a significant amount of spatial variability in PO4-P flux or concentration. Human population density was the single best predictor of DIN flux (r2=0.76, p<0.01), and together with % impervious surface and % agriculture explained 86% (p<0.01) of the total variance. Among all sites, % road pavement was a strong predictor of stream Na+ and Cl- concentrations (r2 = 0.75 to 0.78, p<0.01) and % impervious surface was a stronger predictor (r2 = 0.86 to 0.92, p<0.01) among a subset of sites. Our results suggest that DIN and DON result from different sources in the landscape and although sources of DON and DOC are similar, DON and DOC concentrations respond

  6. Control over structure-specific flexibility improves anatomical accuracy for point-based deformable registration in bladder cancer radiotherapy

    SciTech Connect

    Wognum, S.; Chai, X.; Hulshof, M. C. C. M.; Bel, A.; Bondar, L.; Zolnay, A. G.; Hoogeman, M. S.

    2013-02-15

    Purpose: Future developments in image guided adaptive radiotherapy (IGART) for bladder cancer require accurate deformable image registration techniques for the precise assessment of tumor and bladder motion and deformation that occur as a result of large bladder volume changes during the course of radiotherapy treatment. The aim was to employ an extended version of a point-based deformable registration algorithm that allows control over tissue-specific flexibility in combination with the authors' unique patient dataset, in order to overcome two major challenges of bladder cancer registration, i.e., the difficulty in accounting for the difference in flexibility between the bladder wall and tumor and the lack of visible anatomical landmarks for validation. Methods: The registration algorithm used in the current study is an extension of the symmetric-thin plate splines-robust point matching (S-TPS-RPM) algorithm, a symmetric feature-based registration method. The S-TPS-RPM algorithm has been previously extended to allow control over the degree of flexibility of different structures via a weight parameter. The extended weighted S-TPS-RPM algorithm was tested and validated on CT data (planning- and four to five repeat-CTs) of five urinary bladder cancer patients who received lipiodol injections before radiotherapy. The performance of the weighted S-TPS-RPM method, applied to bladder and tumor structures simultaneously, was compared with a previous version of the S-TPS-RPM algorithm applied to bladder wall structure alone and with a simultaneous nonweighted S-TPS-RPM registration of the bladder and tumor structures. Performance was assessed in terms of anatomical and geometric accuracy. The anatomical accuracy was calculated as the residual distance error (RDE) of the lipiodol markers and the geometric accuracy was determined by the surface distance, surface coverage, and inverse consistency errors. Optimal parameter values for the flexibility and bladder weight

  7. Continental igneous rock composition: A major control of past global chemical weathering

    PubMed Central

    Bataille, Clément P.; Willis, Amy; Yang, Xiao; Liu, Xiao-Ming

    2017-01-01

    The composition of igneous rocks in the continental crust has changed throughout Earth’s history. However, the impact of these compositional variations on chemical weathering, and by extension on seawater and atmosphere evolution, is largely unknown. We use the strontium isotope ratio in seawater [(87Sr/86Sr)seawater] as a proxy for chemical weathering, and we test the sensitivity of (87Sr/86Sr)seawater variations to the strontium isotopic composition (87Sr/86Sr) in igneous rocks generated through time. We demonstrate that the 87Sr/86Sr ratio in igneous rocks is correlated to the epsilon hafnium (εHf) of their hosted zircon grains, and we use the detrital zircon record to reconstruct the evolution of the 87Sr/86Sr ratio in zircon-bearing igneous rocks. The reconstructed 87Sr/86Sr variations in igneous rocks are strongly correlated with the (87Sr/86Sr)seawater variations over the last 1000 million years, suggesting a direct control of the isotopic composition of silicic magmatism on (87Sr/86Sr)seawater variations. The correlation decreases during several time periods, likely reflecting changes in the chemical weathering rate associated with paleogeographic, climatic, or tectonic events. We argue that for most of the last 1000 million years, the (87Sr/86Sr)seawater variations are responding to changes in the isotopic composition of silicic magmatism rather than to changes in the global chemical weathering rate. We conclude that the (87Sr/86Sr)seawater variations are of limited utility to reconstruct changes in the global chemical weathering rate in deep times. PMID:28345044

  8. Continental igneous rock composition: A major control of past global chemical weathering.

    PubMed

    Bataille, Clément P; Willis, Amy; Yang, Xiao; Liu, Xiao-Ming

    2017-03-01

    The composition of igneous rocks in the continental crust has changed throughout Earth's history. However, the impact of these compositional variations on chemical weathering, and by extension on seawater and atmosphere evolution, is largely unknown. We use the strontium isotope ratio in seawater [((87)Sr/(86)Sr)seawater] as a proxy for chemical weathering, and we test the sensitivity of ((87)Sr/(86)Sr)seawater variations to the strontium isotopic composition ((87)Sr/(86)Sr) in igneous rocks generated through time. We demonstrate that the (87)Sr/(86)Sr ratio in igneous rocks is correlated to the epsilon hafnium (εHf) of their hosted zircon grains, and we use the detrital zircon record to reconstruct the evolution of the (87)Sr/(86)Sr ratio in zircon-bearing igneous rocks. The reconstructed (87)Sr/(86)Sr variations in igneous rocks are strongly correlated with the ((87)Sr/(86)Sr)seawater variations over the last 1000 million years, suggesting a direct control of the isotopic composition of silicic magmatism on ((87)Sr/(86)Sr)seawater variations. The correlation decreases during several time periods, likely reflecting changes in the chemical weathering rate associated with paleogeographic, climatic, or tectonic events. We argue that for most of the last 1000 million years, the ((87)Sr/(86)Sr)seawater variations are responding to changes in the isotopic composition of silicic magmatism rather than to changes in the global chemical weathering rate. We conclude that the ((87)Sr/(86)Sr)seawater variations are of limited utility to reconstruct changes in the global chemical weathering rate in deep times.

  9. Nramp1 Is Not a Major Determinant in the Control of Brucella melitensis Infection in Mice

    PubMed Central

    Guilloteau, Laurence A.; Dornand, Jacques; Gross, Antoine; Olivier, Michel; Cortade, Fabienne; Vern, Yves Le; Kerboeuf, Dominique

    2003-01-01

    Brucella, the causative agent of brucellosis in animals and humans, can survive and proliferate within macrophages. Macrophages mediate mouse resistance to various pathogens through the expression of the Nramp1 gene. The role of this gene in the control of Brucella infection was investigated. When BALB/c mice (Nramp1s) and C.CB congenic mice (Nramp1r) were infected with Brucella melitensis, the number of Brucella organisms per spleen was significantly larger in the C.CB mice than in the BALB/c mice during the first week postinfection (p.i.). This Nramp1-linked susceptibility to Brucella was temporary, since similar numbers of Brucella were recovered from the two strains of mice 2 weeks p.i. The effect of Nramp1 expression occurred within splenocytes intracellularly infected by Brucella. However, there was no difference between in vitro replication rates of Brucella in macrophages isolated from the two strains of mice infected in vivo or in Nramp1 RAW264 transfectants. In mice, infection with Brucella induced an inflammatory response, resulting in splenomegaly and recruitment of phagocytes in the spleen, which was amplified in C.CB mice. Reverse transcription-PCR (RT-PCR), performed 5 days p.i., showed that inducible nitric oxide synthase, tumor necrosis factor alpha (TNF-α), interleukin-12 p40 (IL-12p40), gamma interferon (IFN-γ), and IL-10 mRNAs were similarly induced in spleens of the two strains. In contrast, the mRNA of KC, a C-X-C chemokine, was induced only in infected C.CB mice at this time. This pattern of mRNA expression was maintained at 14 days p.i., with IFN-γ and IL-12p40 mRNAs being more intensively induced in the infected C.CB mice, but TNF-α mRNA was no longer induced. The higher recruitment of neutrophils observed in the spleens of infected C.CB mice could explain the temporary susceptibility of C.CB mice to B. melitensis infection. In contrast to infections with Salmonella, Leishmania, and Mycobacterium, the expression of the Nramp1 gene

  10. Reach-scale cation exchange controls on major ion chemistry of an Antarctic glacial meltwater stream

    USGS Publications Warehouse

    Gooseff, Michael N.; McKnight, Diane M.; Runkel, Robert L.

    2004-01-01

    McMurdo dry valleys of Antarctica represent the largest of the ice-free areas on the Antarctic continent, containing glaciers, meltwater streams, and closed basin lakes. Previous geochemical studies of dry valley streams and lakes have addressed chemical weathering reactions of hyporheic substrate and geochemical evolution of dry valley surface waters. We examine cation transport and exchange reactions during a stream tracer experiment in a dry valley glacial meltwater stream. The injection solution was composed of dissolved Li+, Na+, K+, and Cl-. Chloride behaved conservatively in this stream, but Li+, Na+, and K+ were reactive to varying degrees. Mass balance analysis indicates that relative to Cl-, Li+ and K+ were taken up in downstream transport and Na+ was released. Simulations of conservative and reactive (first-order uptake or generation) solute transport were made with the OTIS (one-dimensional solute transport with inflow and storage) model. Among the four experimental reaches of Green Creek, solute transport simulations reveal that Li+ was removed from stream water in all four reaches, K+ was released in two reaches, taken up in one reach, and Na+ was released in all four reaches. Hyporheic sediments appear to be variable with uptake of Li+ in two reaches, uptake of K+ in one reach, release of K+ in two reaches, and uptake of Na+ in one reach. Mass balances of the conservative and reactive simulations show that from 1.05 to 2.19 moles of Li+ was adsorbed per reach, but less than 0.3 moles of K+ and less than 0.9 moles of Na+ were released per reach. This suggests that either (1) exchange of another ion which was not analyzed in this experiment or (2) that both ion exchange and sorption control inorganic solute transport. The elevated cation concentrations introduced during the experiment are typical of initial flows in each flow season, which flush accumulated dry salts from the streambed. We propose that the bed sediments (which compose the hyporheic

  11. Free-Time and Fixed End-Point Optimal Control Theory in Quantum Mechanics: Application to Entanglement Generation

    NASA Astrophysics Data System (ADS)

    Mishima, Kenji; Yamashita, Koichi

    2009-03-01

    We have constructed free-time and fixed end-point optimal control theory for quantum systems and applied it to entanglement generation between rotational modes of two polar molecules coupled by dipole-dipole interaction. The motivation of the present work is to solve optimal control problems more flexibly by extending the popular fixed-time and fixed end-point optimal control theory for quantum systems to free-time and fixed end-point optimal control theory. Our theory can not only achieve high transition probabilities but also determine exact temporal duration of the laser pulses. As a demonstration, our theory is applied to entanglement generation in rotational modes of NaCl-NaBr polar molecular systems that are sensitive to the strength of entangling interactions. Using the tailored laser pulses, we discuss the fidelity of entanglement distillation and quantum teleportation. Our method will significantly be useful for the quantum control of non-local interaction such as entangling interaction, and other time-sensitive general quantum dynamics, chemical reactions.

  12. Design of PID controllers in double feedback loops for SISO systems with set-point filters.

    PubMed

    Vijayan, V; Panda, Rames C

    2012-07-01

    A PID controller is widely used to control industrial processes that are mostly open loop stable or unstable. Selection of proper feedback structure and controller tuning helps to improve the performance of the loop. In this paper a double-feedback loop/method is used to achieve stability and better performance of the process. The internal feedback is used for stabilizing the process and the outer loop is used for good setpoint tracking. An internal model controller (IMC) based PID method is used for tuning the outer loop controller. Autotuning based on relay feedback or the Ziegler-Nichols method can be used for tuning an inner loop controller. A tuning parameter (λ) that is used to tune IMC-PID is used as a time constant of a setpoint filter that is used for reducing the peak overshoot. The method has been tested successfully on many low order processes.

  13. Approaches to Adaptive Active Acoustic Noise Control at a Point Using Feedforward Techniques.

    NASA Astrophysics Data System (ADS)

    Zulch, Peter A.

    Active acoustic noise control systems have been of interest since their birth in the 1930's. The principle is to superimpose on an unwanted noise wave shape its inverse with the intention of destructive interference. This work presents two approaches to this idea. The first approach uses a direct design method to develop a controller using an auto-regressive moving-average (ARMA) model that will be used to condition the primary noise to produce the required anti-noise for cancellation. The development of this approach has shown that the stability of the controller relies heavily on a non-minimum phase model of the secondary noise path. For this reason, a second approach, using a controller consisting of two parts was developed. The first part of the controller is designed to cancel broadband noise and the second part is an adaptive controller designed to cancel periodic noise. A simple technique for identifying the parameters of the broadband controller is developed. An ARMA model is used, and it is shown that its stability is improved by prefiltering the test signal with a minimum-phase inverse of the secondary noise channel. The periodic controller uses an estimate of the fundamental frequency to cancel the first few harmonics of periodic noise. A computationally efficient adaptive technique based on least squares is developed for updating the harmonic controller gains at each time step. Experimental results are included for the broadband controller, the harmonic controller, and the combination of the two algorithms. The advantages of using both techniques in conjunction are shown using test cases involving both broadband noise and periodic noise.

  14. Omega-3 fatty acids in major depressive disorder. A preliminary double-blind, placebo-controlled trial.

    PubMed

    Su, Kuan-Pin; Huang, Shih-Yi; Chiu, Chih-Chiang; Shen, Winston W

    2003-08-01

    Patients with depression have been extensively reported to be associated with the abnormality of omega-3 polyunsaturated fatty acids (PUFAs), including significantly low eicosapentaenoic acid and docosahexaenoic acid in cell tissue contents (red blood cell membrane, plasma, etc.) and dietary intake. However, more evidence is needed to support its relation. In this study, we conducted an 8-week, double-blind, placebo-controlled trial, comparing omega-3 PUFAs (6.6 g/day) [corrected] with placebo, on the top of the usual treatment, in 28 patients with major depressive disorder. Patients in the omega-3 PUFA group had a significantly decreased score on the 21-item Hamilton Rating Scale for Depression than those in the placebo group (P < 0.001). From the preliminary findings in this study, omega-3 PUFAs could improve the short-term course of illness and were well tolerated in patients with major depressive disorder.

  15. Selection and allocation of manual traffic control points and personnel during emergencies.

    PubMed

    Parr, Scott A; Wolshon, Brian; Dixit, Vinayak

    2015-01-01

    Manual traffic control is an intersection control strategy in which law enforcement officers allocate intersection right-of-way to turning movements. Many emergency traffic management plans call for manual traffic control in response to oversaturated roadway conditions. This is because it is thought to more effectively move traffic during temporary surges in demand. The goal of this research was to evaluate the current state-of-the-practice used by the Army Corps of Engineers (ACE) in selecting intersections for manual traffic control and allocating police personnel to them during emergencies. This research uses the emergency traffic management plans developed by the ACE for nine counties in the Maryland Eastern Shore region. This area encompassing 14,318 intersections of which 74 were selected for manual traffic control during emergencies. This work sought to quantify the correlations that exist between intersection attributes and the ACE' decision to allocate officers to control them. The research findings suggest that US routes, State routes, and emergency evacuation routes are statistically significant in determining the need for police control at intersections. Also significant are intersection on contraflow corridors and intersections near grade separated interchanges. The model also determined that intersections isolated from evacuation routes and county exits were more likely to be selected for manual control, indicating that rural areas may rely on manual traffic control in the absence of multilane highway and freeways. This research also found that intersections involving evacuation routes, contraflow corridors, and grade separated interchanges may warrant additional police personnel (two or more officers) for manual traffic control.

  16. Hardware description ADSP-21020 40-bit floating point DSP as designed in a remotely controlled digital CW Doppler radar

    SciTech Connect

    Morrison, R.E.; Robinson, S.H.

    1991-01-01

    A continuous wave Doppler radar system has been designed which is portable, easily deployed, and remotely controlled. The heart of this system is a DSP/control board using Analog Devices ADSP-21020 40-bit floating point digital signal processor (DSP) microprocessor. Two 18-bit audio A/D converters provide digital input to the DSP/controller board for near real time target detection. Program memory for the DSP is dual ported with an Intel 87C51 microcontroller allowing DSP code to be up-loaded or down-loaded from a central controlling computer. The 87C51 provides overall system control for the remote radar and includes a time-of-day/day-of-year real time clock, system identification (ID) switches, and input/output (I/O) expansion by an Intel 82C55 I/O expander. 5 refs., 8 figs., 2 tabs.

  17. Factors Associated with the Combined Use of Antidepressants and Benzodiazepines in Major Depression: A Case-Control Study.

    PubMed

    Fulone, Izabela; Silva, Marcus T; Lopes, Luciane C

    2016-09-01

    The aim of this study was to identify the factors associated with the combined use of antidepressants and benzodiazepines (BDZs) in patients with major depression. We conducted a case-control study in the public health service of the city of São Paulo, Brazil. The participants were all patients being treated with antidepressants, who were diagnosed with major depression. Patients who received a combination of antidepressants and BDZs were classified as cases, and those who used only antidepressants, as controls. Data were obtained from a pharmacy database, medical records and interviews with the healthcare team. The association of predisposing factors for combined therapy was analysed using logistic regression analysis, and the odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Of the 1355 users of antidepressants, 265 had major depression, of whom 138 were cases and 127 were controls. The factors associated with combined use were age older than 35 years (OR 2.2, 95% CI 1.0-4.7), absence of comorbidities (OR 2.3, 95% CI 1.4-4.1) and no use of other drugs (OR 1.9, 95% CI 1.1-3.3). Patients with combined use were more likely to exhibit inadequate prescribing, including inappropriate antidepressants (OR 4.7, 95% CI 2.2-9.9), inadequate dosages (OR 3.62, 95% CI 1.4-9.6) and/or a non-recommended duration (OR 66.6, 95% CI 18.4-240.7). The factors identified showed the groups most susceptible to combined use in this population, who in turn are more likely to receive inappropriate prescriptions.

  18. A novel auto-bias control scheme for stabilizing lithium niobate Mach-Zehnder modulator at any operating point

    NASA Astrophysics Data System (ADS)

    Tao, Jin-jing; Zhang, Yang-an; Zhang, Jin-nan; Yuan, Xue-guang; Huang, Yong-qing; Li, Yu-peng

    2014-01-01

    In this paper, we propose and experimentally demonstrate an auto-bias control scheme for stabilizing a lithium niobate (LN) Mach-Zehnder modulator (MZM) at any operating point along the power transmission curve. It is based on that the bias drift would change the operating point and result in varying the output optical average power of the Mach-Zehnder modulator and its first and second derivatives. The ratio of the first to the second derivative of the output optical average power is used in the proposed scheme as the key parameter. The experimental results show that the output optical average power of the LN MZM hardly changes at the desired operating point, and the maximum deviation of output optical average power is less than ±4%.

  19. Control and automation of the Pegasus multi-point Thomson scattering system

    DOE PAGES

    Bodner, Grant M.; Bongard, Michael W.; Fonck, Raymond J.; ...

    2016-08-12

    A new control system for the Pegasus Thomson scattering diagnostic has recently been deployed to automate the laser operation, data collection process, and interface with the system-wide Pegasus control code. Automation has been extended to areas outside of data collection, such as manipulation of beamline cameras and remotely controlled turning mirror actuators to enable intra-shot beam alignment. In addition, the system has been upgraded with a set of fast (~1 ms) mechanical shutters to mitigate contamination from background light. Modification and automation of the Thomson system have improved both data quality and diagnostic reliability.

  20. Control and automation of the Pegasus multi-point Thomson scattering system

    NASA Astrophysics Data System (ADS)

    Bodner, G. M.; Bongard, M. W.; Fonck, R. J.; Reusch, J. A.; Rodriguez Sanchez, C.; Schlossberg, D. J.

    2016-11-01

    A new control system for the Pegasus Thomson scattering diagnostic has recently been deployed to automate the laser operation, data collection process, and interface with the system-wide Pegasus control code. Automation has been extended to areas outside of data collection, such as manipulation of beamline cameras and remotely controlled turning mirror actuators to enable intra-shot beam alignment. Additionally, the system has been upgraded with a set of fast (˜1 ms) mechanical shutters to mitigate contamination from background light. Modification and automation of the Thomson system have improved both data quality and diagnostic reliability.

  1. Control and automation of the Pegasus multi-point Thomson scattering system.

    PubMed

    Bodner, G M; Bongard, M W; Fonck, R J; Reusch, J A; Rodriguez Sanchez, C; Schlossberg, D J

    2016-11-01

    A new control system for the Pegasus Thomson scattering diagnostic has recently been deployed to automate the laser operation, data collection process, and interface with the system-wide Pegasus control code. Automation has been extended to areas outside of data collection, such as manipulation of beamline cameras and remotely controlled turning mirror actuators to enable intra-shot beam alignment. Additionally, the system has been upgraded with a set of fast (∼1 ms) mechanical shutters to mitigate contamination from background light. Modification and automation of the Thomson system have improved both data quality and diagnostic reliability.

  2. Hazard Analysis and Critical Control Points among Chinese Food Business Operators

    PubMed Central

    Amadei, Paolo; Masotti, Gianfranco; Condoleo, Roberto; Guidi, Alessandra

    2014-01-01

    The purpose of the present paper is to highlight some critical situations emerged during the implementation of long-term projects locally managed by Prevention Services, to control some manufacturing companies in Rome and Prato, Central Italy. In particular, some critical issues on the application of self-control in marketing and catering held by Chinese operators are underlined. The study showed serious flaws in preparing and controlling of manuals for good hygiene practice, participating of the consultants among food business operators (FBOs) to the control of the procedures. Only after regular actions by the Prevention Services, there have been satisfying results. This confirms the need to have qualified and expert partners able to promptly act among FBOs and to give adequate support to authorities in charge in order to guarantee food safety. PMID:27800356

  3. Perceived Effects of Hazard Analysis and Critical Control Point Training on California Egg Producers

    DTIC Science & Technology

    2000-05-25

    quality assurance plan development, egg processing, flock health, biosecurity and cleaning/disinfection, and pest management /vector control. Pullet...producers rated the egg processing module to be less valuable than pest management training. All other sectors found all training modules to be...training and were most likely to make changes in the area of pest management /vector control. Participants did not increase use of veterinary

  4. LiveWire interactive boundary extraction algorithm based on Haar wavelet transform and control point set direction search

    NASA Astrophysics Data System (ADS)

    Cheng, Jun; Zhang, Jun; Tian, Jinwen

    2015-12-01

    Based on deep analysis of the LiveWire interactive boundary extraction algorithm, a new algorithm focusing on improving the speed of LiveWire algorithm is proposed in this paper. Firstly, the Haar wavelet transform is carried on the input image, and the boundary is extracted on the low resolution image obtained by the wavelet transform of the input image. Secondly, calculating LiveWire shortest path is based on the control point set direction search by utilizing the spatial relationship between the two control points users provide in real time. Thirdly, the search order of the adjacent points of the starting node is set in advance. An ordinary queue instead of a priority queue is taken as the storage pool of the points when optimizing their shortest path value, thus reducing the complexity of the algorithm from O[n2] to O[n]. Finally, A region iterative backward projection method based on neighborhood pixel polling has been used to convert dual-pixel boundary of the reconstructed image to single-pixel boundary after Haar wavelet inverse transform. The algorithm proposed in this paper combines the advantage of the Haar wavelet transform and the advantage of the optimal path searching method based on control point set direction search. The former has fast speed of image decomposition and reconstruction and is more consistent with the texture features of the image and the latter can reduce the time complexity of the original algorithm. So that the algorithm can improve the speed in interactive boundary extraction as well as reflect the boundary information of the image more comprehensively. All methods mentioned above have a big role in improving the execution efficiency and the robustness of the algorithm.

  5. Active control on high-order coherence and statistic characterization on random phase fluctuation of two classical point sources

    PubMed Central

    Hong, Peilong; Li, Liming; Liu, Jianji; Zhang, Guoquan

    2016-01-01

    Young’s double-slit or two-beam interference is of fundamental importance to understand various interference effects, in which the stationary phase difference between two beams plays the key role in the first-order coherence. Different from the case of first-order coherence, in the high-order optical coherence the statistic behavior of the optical phase will play the key role. In this article, by employing a fundamental interfering configuration with two classical point sources, we showed that the high- order optical coherence between two classical point sources can be actively designed by controlling the statistic behavior of the relative phase difference between two point sources. Synchronous position Nth-order subwavelength interference with an effective wavelength of λ/M was demonstrated, in which λ is the wavelength of point sources and M is an integer not larger than N. Interestingly, we found that the synchronous position Nth-order interference fringe fingerprints the statistic trace of random phase fluctuation of two classical point sources, therefore, it provides an effective way to characterize the statistic properties of phase fluctuation for incoherent light sources. PMID:27021589

  6. Active control on high-order coherence and statistic characterization on random phase fluctuation of two classical point sources.

    PubMed

    Hong, Peilong; Li, Liming; Liu, Jianji; Zhang, Guoquan

    2016-03-29

    Young's double-slit or two-beam interference is of fundamental importance to understand various interference effects, in which the stationary phase difference between two beams plays the key role in the first-order coherence. Different from the case of first-order coherence, in the high-order optical coherence the statistic behavior of the optical phase will play the key role. In this article, by employing a fundamental interfering configuration with two classical point sources, we showed that the high- order optical coherence between two classical point sources can be actively designed by controlling the statistic behavior of the relative phase difference between two point sources. Synchronous position Nth-order subwavelength interference with an effective wavelength of λ/M was demonstrated, in which λ is the wavelength of point sources and M is an integer not larger than N. Interestingly, we found that the synchronous position Nth-order interference fringe fingerprints the statistic trace of random phase fluctuation of two classical point sources, therefore, it provides an effective way to characterize the statistic properties of phase fluctuation for incoherent light sources.

  7. [Urban non-point source pollution control by runoff retention and filtration pilot system].

    PubMed

    Bai, Yao; Zuo, Jian-E; Gan, Li-Li; Low, Thong Soon; Miao, Heng-Feng; Ruan, Wen-Quan; Huang, Xia

    2011-09-01

    A runoff retention and filtration pilot system was designed and the long-term purification effect of the runoff was monitored. Runoff pollution characters in 2 typical events and treatment effect of the pilot system were analyzed. The results showed that the runoff was severely polluted. Event mean concentrations (EMCs) of SS, COD, TN and TP in the runoff were 361, 135, 7.88 and 0.62 mg/L respectively. The runoff formed by long rain presented an obvious first flush effect. The first 25% flow contributed more than 50% of the total pollutants loading of SS, TP, DTP and PO4(3-). The pilot system could reduce 100% of the non-point source pollution if the volume of the runoff was less than the retention tank. Otherwise the overflow will be purification by the filtration pilot system and the removal rates of SS, COD, TN, TP, DTP and PO4(3-) reached 97.4% , 61.8%, 22.6%, 85.1%, 72.1%, and 85.2% respectively. The system was stable and the removal rate of SS, COD, TN, and TP were 98.6%, 65.4%, 55.1% and 92.6%. The whole system could effectively remove the non-point source pollution caused by runoff.

  8. Tracking and Pointing of Target by a Bifocal Relay Mirror Spacecraft Using Attitude Control and Fast Steering Mirrors Tilting

    DTIC Science & Technology

    2002-08-01

    proposed for the tracking and pointing of the target of the Bifocal Relay Mirror. The attitude control system consists of reaction wheels , star trackers and...nautics, Inc. with permission. T Transmitter portion of the spacecraft w Reaction wheel m Mirror rel Relative B Acronyms BRM Bifocal Relay Mirror...tem are respectively OR and OS . The other bodies considered in the dynamic model are: • four reaction wheels mounted in tetrahedral configuration on

  9. Design of state-feedback controllers including sensitivity reduction, with applications to precision pointing

    NASA Technical Reports Server (NTRS)

    Hadass, Z.

    1974-01-01

    The design procedure of feedback controllers was described and the considerations for the selection of the design parameters were given. The frequency domain properties of single-input single-output systems using state feedback controllers are analyzed, and desirable phase and gain margin properties are demonstrated. Special consideration is given to the design of controllers for tracking systems, especially those designed to track polynomial commands. As an example, a controller was designed for a tracking telescope with a polynomial tracking requirement and some special features such as actuator saturation and multiple measurements, one of which is sampled. The resulting system has a tracking performance comparing favorably with a much more complicated digital aided tracker. The parameter sensitivity reduction was treated by considering the variable parameters as random variables. A performance index is defined as a weighted sum of the state and control convariances that sum from both the random system disturbances and the parameter uncertainties, and is minimized numerically by adjusting a set of free parameters.

  10. Major depressive disorder with subthreshold hypomania (mixed features): Clinical characteristics of patients entered in a multiregional, placebo-controlled study.

    PubMed

    Targum, Steven D; Suppes, Trisha; Pendergrass, J Cara; Lee, Sang; Silva, Robert; Cucchiaro, Josephine; Loebel, Antony

    2016-07-04

    Major depressive disorder (MDD) associated with subthreshold hypomanic symptoms (mixed features), has been identified as a distinct nosological entity in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). We identified the predominant manic symptoms present at baseline in a multiregional, placebo-controlled trial involving 211 patients with MDD with mixed features (Clinicaltrials.govNCT01421134). Patients with 2 or 3 DSM-5 criteria defined manic symptoms were eligible for the study. At study baseline, increased talkativeness (pressure to keep talking) and flight of ideas (racing thoughts) were endorsed by approximately 65% of patients and a decreased need for sleep was endorsed by 40% of patients. Approximately 60% of patients also endorsed irritability and distractibility at baseline although these symptoms are not generally counted as part of the "mixed" depression diagnosis as they may overlap with criteria for MDD. Thus, five clinical symptoms characterized the manic presentation in the majority of patients diagnosed as having MDD with "mixed" features in this first placebo-controlled trial examining the use of a psychotropic medication (lurasidone) in this population. Our findings support the designation of MDD with mixed features specifier and suggest that this subpopulation of depressed patients may warrant additional medication beyond antidepressants.

  11. Precision Pointing Control to and Accurate Target Estimation of a Non-Cooperative Vehicle

    NASA Technical Reports Server (NTRS)

    VanEepoel, John; Thienel, Julie; Sanner, Robert M.

    2006-01-01

    In 2004, NASA began investigating a robotic servicing mission for the Hubble Space Telescope (HST). Such a mission would not only require estimates of the HST attitude and rates in order to achieve capture by the proposed Hubble Robotic Vehicle (HRV), but also precision control to achieve the desired rate and maintain the orientation to successfully dock with HST. To generalize the situation, HST is the target vehicle and HRV is the chaser. This work presents a nonlinear approach for estimating the body rates of a non-cooperative target vehicle, and coupling this estimation to a control scheme. Non-cooperative in this context relates to the target vehicle no longer having the ability to maintain attitude control or transmit attitude knowledge.

  12. Method for controlling boiling point distribution of coal liquefaction oil product

    DOEpatents

    Anderson, R.P.; Schmalzer, D.K.; Wright, C.H.

    1982-12-21

    The relative ratio of heavy distillate to light distillate produced in a coal liquefaction process is continuously controlled by automatically and continuously controlling the ratio of heavy distillate to light distillate in a liquid solvent used to form the feed slurry to the coal liquefaction zone, and varying the weight ratio of heavy distillate to light distillate in the liquid solvent inversely with respect to the desired weight ratio of heavy distillate to light distillate in the distillate fuel oil product. The concentration of light distillate and heavy distillate in the liquid solvent is controlled by recycling predetermined amounts of light distillate and heavy distillate for admixture with feed coal to the process in accordance with the foregoing relationships. 3 figs.

  13. Method for controlling boiling point distribution of coal liquefaction oil product

    DOEpatents

    Anderson, Raymond P.; Schmalzer, David K.; Wright, Charles H.

    1982-12-21

    The relative ratio of heavy distillate to light distillate produced in a coal liquefaction process is continuously controlled by automatically and continuously controlling the ratio of heavy distillate to light distillate in a liquid solvent used to form the feed slurry to the coal liquefaction zone, and varying the weight ratio of heavy distillate to light distillate in the liquid solvent inversely with respect to the desired weight ratio of heavy distillate to light distillate in the distillate fuel oil product. The concentration of light distillate and heavy distillate in the liquid solvent is controlled by recycling predetermined amounts of light distillate and heavy distillate for admixture with feed coal to the process in accordance with the foregoing relationships.

  14. Chandra X-Ray Observatory Pointing Control System Performance During Transfer Orbit and Initial On-Orbit Operations

    NASA Technical Reports Server (NTRS)

    Quast, Peter; Tung, Frank; West, Mark; Wider, John

    2000-01-01

    The Chandra X-ray Observatory (CXO, formerly AXAF) is the third of the four NASA great observatories. It was launched from Kennedy Space Flight Center on 23 July 1999 aboard the Space Shuttle Columbia and was successfully inserted in a 330 x 72,000 km orbit by the Inertial Upper Stage (IUS). Through a series of five Integral Propulsion System burns, CXO was placed in a 10,000 x 139,000 km orbit. After initial on-orbit checkout, Chandra's first light images were unveiled to the public on 26 August, 1999. The CXO Pointing Control and Aspect Determination (PCAD) subsystem is designed to perform attitude control and determination functions in support of transfer orbit operations and on-orbit science mission. After a brief description of the PCAD subsystem, the paper highlights the PCAD activities during the transfer orbit and initial on-orbit operations. These activities include: CXO/IUS separation, attitude and gyro bias estimation with earth sensor and sun sensor, attitude control and disturbance torque estimation for delta-v burns, momentum build-up due to gravity gradient and solar pressure, momentum unloading with thrusters, attitude initialization with star measurements, gyro alignment calibration, maneuvering and transition to normal pointing, and PCAD pointing and stability performance.

  15. A double-loop structure in the adaptive generalized predictive control algorithm for control of robot end-point contact force.

    PubMed

    Wen, Shuhuan; Zhu, Jinghai; Li, Xiaoli; Chen, Shengyong

    2014-09-01

    Robot force control is an essential issue in robotic intelligence. There is much high uncertainty when robot end-effector contacts with the environment. Because of the environment stiffness effects on the system of the robot end-effector contact with environment, the adaptive generalized predictive control algorithm based on quantitative feedback theory is designed for robot end-point contact force system. The controller of the internal loop is designed on the foundation of QFT to control the uncertainty of the system. An adaptive GPC algorithm is used to design external loop controller to improve the performance and the robustness of the system. Two closed loops used in the design approach realize the system׳s performance and improve the robustness. The simulation results show that the algorithm of the robot end-effector contacting force control system is effective.

  16. Riluzole combination therapy for moderate-to-severe major depressive disorder: A randomized, double-blind, placebo-controlled trial.

    PubMed

    Salardini, Elaheh; Zeinoddini, Atefeh; Mohammadinejad, Payam; Khodaie-Ardakani, Mohammad-Reza; Zahraei, Nagmeh; Zeinoddini, Arefeh; Akhondzadeh, Shahin

    2016-04-01

    Recent evidences suggest that glutamatergic dysregulation implicated in neural plasticity and cellular resilience may contribute to the pathophysiology of Major Depressive Disorder (MDD). Riluzole, which exerts its effect by targeting glutamate neurotransmission, has shown antidepressant effect in recent preclinical, observational and open label studies. This study aimed to assess the efficacy and tolerability of riluzole in patients with MDD. Sixty-four inpatients with diagnosis of moderate to severe major depressive disorder participated in a parallel, randomized, controlled trial, and sixty patients underwent 6 weeks treatment with either riluzole (50 mg/bid) plus citalopram (40 mg/day) or placebo plus citalopram (40 mg/day). All participants were inpatients for the whole duration of the study. Patients were assessed using Hamilton depression rating scale (HDRS) at baseline and weeks 2, 4 and 6. The primary outcome measure was to assess the efficacy of riluzole compared to placebo in improving the depressive symptoms. General linear model repeated measures demonstrated significant effect for time × treatment interaction on HDRS [F (1.86, 107.82) = 8.63, p < 0.001]. Significantly greater improvement was observed in HDRS scores in the riluzole group compared to the placebo group from baseline HDRS score at weeks 2, 4 and 6 (p < 0.001, p = 0.001, p = 0.002, respectively). Significantly greater response with greater speed to treatment was observed in the riluzole group than the placebo group. No serious adverse event occurred. This study showed a favorable safety and efficacy profile in patients with major depressive disorder. Larger controlled studies with longer treatment periods are needed to investigate long term safety, efficacy and optimal dosing.

  17. Assessment of Autonomic Control and Respiratory Sinus Arrhythmia Using Point Process Models of Human Heart Beat Dynamics

    PubMed Central

    Chen, Zhe; Brown, Emery N.; Barbieri, Riccardo

    2009-01-01

    Tracking the autonomic control and respiratory sinus arrhythmia (RSA) from electrocardiogram and respiratory measurements is an important problem in cardiovascular control. We propose a point process adaptive filter algorithm based on an inverse Gaussian model to track heart beat intervals that incorporates respiratory measurements as a covariate and provides an analytic form for computing a dynamic estimate of RSA gain. We use Kolmogorov-Smirnov tests and autocorrelation function analyses to assess model goodness-of-fit. We illustrate the properties of the new dynamic estimate of RSA in the analysis of simulated heart beat data and actual heart beat data recorded from subjects in a four-state postural study of heart beat dynamics: control, sympathetic blockade, parasympathetic blockade, and combined sympathetic and parasympathetic blockade. In addition to giving an accurate description of the heart beat data, our adaptive filter algorithm confirms established findings pointing at a vagally mediated RSA, and it provides a new dynamic RSA estimate that can be used to track cardiovascular control between and within a broad range of postural, pharmacological and age conditions. Our paradigm suggests a possible framework for designing a device for ambulatory monitoring and assessment of autonomic control in both laboratory research and clinical practice. PMID:19272971

  18. Design and Integration of an All-Magnetic Attitude Control System for FASTSAT-HSV01's Multiple Pointing Objectives

    NASA Technical Reports Server (NTRS)

    DeKock, Brandon; Sanders, Devon; Vanzwieten, Tannen; Capo-Lugo, Pedro

    2011-01-01

    The FASTSAT-HSV01 spacecraft is a microsatellite with magnetic torque rods as it sole attitude control actuator. FASTSAT s multiple payloads and mission functions require the Attitude Control System (ACS) to maintain Local Vertical Local Horizontal (LVLH)-referenced attitudes without spin-stabilization, while the pointing errors for some attitudes be significantly smaller than the previous best-demonstrated for this type of control system. The mission requires the ACS to hold multiple stable, unstable, and non-equilibrium attitudes, as well as eject a 3U CubeSat from an onboard P-POD and recover from the ensuing tumble. This paper describes the Attitude Control System, the reasons for design choices, how the ACS integrates with the rest of the spacecraft, and gives recommendations for potential future applications of the work.

  19. Effects of cortisol on hippocampal subfields volumes and memory performance in healthy control subjects and patients with major depressive disorder.

    PubMed

    Travis, Scott G; Coupland, Nicholas J; Hegadoren, K; Silverstone, Peter H; Huang, Yushan; Carter, Rawle; Fujiwara, Esther; Seres, Peter; Malykhin, Nikolai V

    2016-09-01

    Overactivity of the hypothalamic-pituitary-adrenal (HPA) axis in major depressive disorder (MDD) is among the most consistently replicated biological findings in psychiatry. Magnetic resonance imaging (MRI) studies have consistently demonstrated that hippocampal (HC) volume is decreased in patients with MDD. The improved spatial resolution of high field strength MRI has recently enabled measurements of HC subfield volumes in vivo. The main goal of the present study was to examine the relationship between cortisol concentrations over a day and HC subfield volumes in patients with MDD compared to healthy controls and to investigate whether diurnal cortisol measures are related to memory performance. Fourteen MDD patients with moderate or severe episodes were recruited, together with 14 healthy controls. Imaging was performed using a 4.7T whole-body imaging system. HC subfields and subregions were segmented manually using previously defined protocol. Memory performance was assessed using the Wechsler Memory Scale IV. The salivary cortisol levels were measured over the course of one day. We found that cortisol awakening response to 8h (CAR-8h) was higher in MDD patients compared to controls and that this increase in CAR-8h in MDD patients correlated negatively with left total Cornu Ammonis (CA)1-3 and left HC head volume. In healthy controls mean cortisol levels were negatively associated with right total CA1-3, right HC head, and right total HC volume. In addition, in healthy controls higher CAR-8h was related to worse performance on the immediate content memory. These results provide the first in vivo evidence of the negative associations between cortisol level, CA1-3 HC subfield volume and memory performance in patients with MDD and healthy controls.

  20. Pitch Characteristics Before Ulnar Collateral Ligament Reconstruction in Major League Pitchers Compared With Age-Matched Controls

    PubMed Central

    Prodromo, John; Patel, Nimit; Kumar, Neil; Denehy, Kevin; Tabb, Loni Philip; Tom, James

    2016-01-01

    Background: Ulnar collateral ligament reconstruction (UCLR) is commonly performed in Major League Baseball (MLB) pitchers, but little is known about the preoperative pitch type and velocity characteristics of pitchers who go on to undergo UCLR. Hypothesis: Pitchers who required UCLR have thrown a greater percentage of fastballs and have greater pitch velocities compared with age-matched controls in the season before injury. Study Design: Case-control study; Level of evidence, 3. Methods: MLB pitchers active during the 2002 to 2015 seasons were included. The UCLR group consisted of MLB pitchers who received UCLR between 2003 and 2015, utilizing the season before surgery (2002-2014) for analysis. The control group comprised age-matched controls of the same season. Players who pitched less than 20 innings in the season before surgery were excluded. Pitch types were recorded as percentage of total pitches thrown. Pitch velocities were recorded for each pitch type. Pitch type and pitch velocities during preoperative seasons for UCLR pitchers were compared with age-matched controls using univariate and multivariate models. Results: A total of 114 cases that went on to UCLR and 3780 controls were included in the study. Pitchers who went on to UCLR appear to have greater fastball, slider, curveball, changeup, and split-fingered fastball velocities; there were no significant differences in pitch selection between the 2 groups. Conclusion: In the season before surgery, MLB pitchers who underwent UCLR demonstrated greater fastball, slider, curveball, changeup, and split-fingered fastball velocities, with no significant difference in pitch type. PMID:27350954

  1. New Research on Multitasking Points to Role of Self-Control

    ERIC Educational Resources Information Center

    Sparks, Sarah D.

    2012-01-01

    For a generation of children immersed in technology, emerging research suggests that while the temptation to multitask may be pervasive, the ability to control it could be the real bellwether of academic success. The pervasiveness of technology and social media, coupled with a fear of missing out on something important, has led students to pay…

  2. Access Point Analysis: What Do Adolescents in South Africa Say about Tobacco Control Programmes?

    ERIC Educational Resources Information Center

    Swart, Dehran; Panday, Saadhna; Reddy, S Priscilla; Bergstrom, Erik; de Vries, Hein

    2006-01-01

    This paper explores adolescent preferences for the setting, timing, delivery format, provider and key elements of tobacco control programmes. The need for programme sensitivity towards urban/rural, gender and ethnic subgroups is also discussed. Schools were purposively selected from the Southern Cape-Karoo Region, South Africa. Twelve prevention…

  3. DEXAMETHASONE SUPPRESSION TEST FOR MAJOR DEPRESSION

    PubMed Central

    Ghulam, R.; Anand, Mohini; Lal, Narottam; Trivedi, J.K.

    1985-01-01

    SUMMARY Overnight post dexamethasone plasma Cortisol levels were estimated in thirty patients of major depression and 30 controls. The cut-off point after which post dexamethasone plasma Cortisol level could be considered abnormal, in patients of major depression, has been worked out at 15 μg/dl in the present study. The results are discussed. PMID:21927130

  4. SU-E-T-72: A Retrospective Correlation Analysis On Dose-Volume Control Points and Treatment Outcomes

    SciTech Connect

    Roy, A; Nohadani, O; Refaat, T; Bacchus, I; Cutright, D; Sathiaseelan, V; Mittal, B

    2015-06-15

    Purpose: To quantify correlation between dose-volume control points and treatment outcomes. Specifically, two outcomes are analyzed: occurrence of radiation induced dysphagia and target complications. The results inform the treatment planning process when competing dose-volume criteria requires relaxations. Methods: 32 patients, treated with whole-field sequential intensity modulated radiation therapy during 2009–2010 period, are considered for this study. Acute dysphagia that is categorized into 3 grades is observed on all patients. 3 patients are observed in grade 1, 17 patients in grade 2, and 12 patients in grade 3. Ordinal logistic regression is employed to establish correlations between grades of dysphagia and dose to cervico-thoracic esophagus. Particularly, minimum (Dmin), mean (Dmean), and maximum (Dmax) dose control points are analyzed. Additionally, target complication, which includes local-regional recurrence and/or distant metastasis, is observed on 4 patients. Binary logistic regression is used to quantify correlation between target complication and four dose control points. Namely, ICRU recommended dose control points, D2, D50, D95, and D98 are analyzed. Results: For correlation with dysphagia, Dmin on cervico-thoracic esophagus is statistically significant (p-value = 0.005). Additionally, Dmean on cervico-thoracic esophagus is also significant in association with dysphagia (p-value = 0.012). However, no correlation was observed between Dmax and dysphagia (p-value = 0.263). For target complications, D50 on the target is a statistically significant dose control point (p-value = 0.032). No correlations were observed between treatment complications and D2 (p-value = 0.866), D95 (p-value = 0.750), and D98 (p-value = 0.710) on the target. Conclusion: Significant correlations are observed between radiation induced dysphagia and Dmean (and Dmin) to cervico-thoracic esophagus. Additionally, correlation between target complications and median dose to target

  5. A Randomized Double-Blind Sham-Controlled Study of Transcranial Direct Current Stimulation for Treatment-Resistant Major Depression

    PubMed Central

    Blumberger, Daniel M.; Tran, Lisa C.; Fitzgerald, Paul B.; Hoy, Kate E.; Daskalakis, Zafiris J.

    2012-01-01

    Objectives: Transcranial direct current stimulation (tDCS) has demonstrated some efficacy in treatment-resistant major depression (TRD). The majority of previous controlled studies have used anodal stimulation to the left dorsolateral prefrontal cortex (DLPFC) and a control location such as the supraorbital region for the cathode. Several open-label studies have suggested effectiveness from anodal stimulation to the left DLPFC combined with cathodal stimulation to the right DLPFC. Thus, this study evaluated the efficacy of tDCS using anodal stimulation to the left DLPFC and cathodal stimulation to the right DLPFC compared to sham tDCS. Methods: Subjects between the ages of 18 and 65 were recruited from a tertiary care university hospital. Twenty-four subjects with TRD and a 17-item Hamilton Rating Scale for Depression greater than 21 were randomized to receive tDCS or sham tDCS. The rates of remission were compared between the two treatment groups. Results: The remission rates did not differ significantly between the two groups using an intention to treat analysis. More subjects in the active tDCS group had failed a course of electroconvulsive therapy in the current depressive episode. Side effects did not differ between the two groups and in general the treatment was very well tolerated. Conclusion: Anodal stimulation to the left DLPFC and cathodal stimulation to the right DLPFC was not efficacious in TRD. However, a number of methodological limitations warrant caution in generalizing from this study. Ongoing, controlled studies should provide further clarification on the efficacy of this stimulation configuration in TRD. ClinicalTrials.gov Identifier: NCT01078948. PMID:22912618

  6. A Randomized, Placebo-Controlled, Active-Reference, Double-Blind, Flexible-Dose Study of the Efficacy of Vortioxetine on Cognitive Function in Major Depressive Disorder.

    PubMed

    Mahableshwarkar, Atul R; Zajecka, John; Jacobson, William; Chen, Yinzhong; Keefe, Richard S E

    2015-07-01

    This multicenter, randomized, double-blind, placebo-controlled, active-referenced (duloxetine 60 mg), parallel-group study evaluated the short-term efficacy and safety of vortioxetine (10-20 mg) on cognitive function in adults (aged 18-65 years) diagnosed with major depressive disorder (MDD) who self-reported cognitive dysfunction. Efficacy was evaluated using ANCOVA for the change from baseline to week 8 in the digit symbol substitution test (DSST)-number of correct symbols as the prespecified primary end point. The patient-reported perceived deficits questionnaire (PDQ) and physician-assessed clinical global impression (CGI) were analyzed in a prespecified hierarchical testing sequence as key secondary end points. Additional predefined end points included the objective performance-based University of San Diego performance-based skills assessment (UPSA) (ANCOVA) to measure functionality, MADRS (MMRM) to assess efficacy in depression, and a prespecified multiple regression analysis (path analysis) to calculate direct vs indirect effects of vortioxetine on cognitive function. Safety and tolerability were assessed at all visits. Vortioxetine was statistically superior to placebo on the DSST (P < 0.05), PDQ (P < 0.01), CGI-I (P < 0.001), MADRS (P < 0.05), and UPSA (P < 0.001). Path analysis indicated that vortioxetine's cognitive benefit was primarily a direct treatment effect rather than due to alleviation of depressive symptoms. Duloxetine was not significantly different from placebo on the DSST or UPSA, but was superior to placebo on the PDQ, CGI-I, and MADRS. Common adverse events (incidence ⩾ 5%) for vortioxetine were nausea, headache, and diarrhea. In this study of MDD adults who self-reported cognitive dysfunction, vortioxetine significantly improved cognitive function, depression, and functionality and was generally well tolerated.

  7. PointCom: Semi-Autonomous UGV Control With Intuitive Interface

    DTIC Science & Technology

    2009-01-01

    Steven M. Rohdea, James Overholtc, Graham Fioranid aQuantum Signal LLC, 3741 Plaza Drive , Ann Arbor, MI, USA 48108; bRobotic Mobility Group...NAME(S) AND ADDRESS(ES) Quantum Signal LLC,3741 Plaza Drive ,Ann Arbor,MI,48108 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING...gaming hardware (“PS2” or “ Xbox ” style controllers) for use with their vehicle, this represents only a minor leveraging of the technology and expertise

  8. Putative transcriptomic biomarkers in the inflammatory cytokine pathway differentiate major depressive disorder patients from control subjects and bipolar disorder patients.

    PubMed

    Powell, Timothy R; McGuffin, Peter; D'Souza, Ursula M; Cohen-Woods, Sarah; Hosang, Georgina M; Martin, Charlotte; Matthews, Keith; Day, Richard K; Farmer, Anne E; Tansey, Katherine E; Schalkwyk, Leonard C

    2014-01-01

    Mood disorders consist of two etiologically related, but distinctly treated illnesses, major depressive disorder (MDD) and bipolar disorder (BPD). These disorders share similarities in their clinical presentation, and thus show high rates of misdiagnosis. Recent research has revealed significant transcriptional differences within the inflammatory cytokine pathway between MDD patients and controls, and between BPD patients and controls, suggesting this pathway may possess important biomarker properties. This exploratory study attempts to identify disorder-specific transcriptional biomarkers within the inflammatory cytokine pathway, which can distinguish between control subjects, MDD patients and BPD patients. This is achieved using RNA extracted from subject blood and applying synthesized complementary DNA to quantitative PCR arrays containing primers for 87 inflammation-related genes. Initially, we use ANOVA to test for transcriptional differences in a 'discovery cohort' (total n = 90) and then we use t-tests to assess the reliability of any identified transcriptional differences in a 'validation cohort' (total n = 35). The two most robust and reliable biomarkers identified across both the discovery and validation cohort were Chemokine (C-C motif) ligand 24 (CCL24) which was consistently transcribed higher amongst MDD patients relative to controls and BPD patients, and C-C chemokine receptor type 6 (CCR6) which was consistently more lowly transcribed amongst MDD patients relative to controls. Results detailed here provide preliminary evidence that transcriptional measures within inflammation-related genes might be useful in aiding clinical diagnostic decision-making processes. Future research should aim to replicate findings detailed in this exploratory study in a larger medication-free sample and examine whether identified biomarkers could be used prospectively to aid clinical diagnosis.

  9. Working-point control technique for the homodyne interferometry in hydrophone calibration

    NASA Astrophysics Data System (ADS)

    Yang, Ping; Xing, Guangzhen

    2015-02-01

    The stabilization of a homodyne type Michelson interferometer for calibrating the high frequency hydrophone is presented in this article. For the detection of the ultrasonic field, a 5 um thickness pellicle was inserted in water moving in sympathy with the ultrasonic wave. To ensure high signal to noise ratio at high frequencies, a 5 MHz focusing transducer was driven by high voltage and harmonics of the shocked ultrasonic field could be activated. Nevertheless, the homodyne interferometer suffered from the drawback of signal fading caused by the low frequency noise in environment, including acoustic noise and water surface agitation. Direct Current Phase Tracking was utilized to maintain the quadrature working point for the interferometer. Most of environmental noises could be effectively compensated while stabilization was maintained. A piezoelectric actuator supporting the reference mirror was utilized as the stabilizing element whose output was frequency independent over the low frequency disturbances, usually below 200 Hz. The ultrasonic signal fading caused by environmental disturbances could be solved while the negative electric feedback loop was operating. The displacement and voltage output of the hydrophone under test were then processed by DFT to derive the fundamental and harmonic components. Under plane wave conditions, the ultrasonic pressure could be derived by the detected displacement with a stabilized homodyne interferometer, and the hydrophone could then be calibrated. Measurement results indicated that the hydrophone calibration system based on the active stabilization of homodyne interferometry was sound in theory and feasible in practice.

  10. Public Support for Family Smoking Prevention and Tobacco Control Act Point-of-Sale Provisions: Results of a National Study

    PubMed Central

    Emery, Sherry L.; Ennett, Susan; McNaughton Reyes, Heath Luz; Scott, John C.; Ribisl, Kurt M.

    2015-01-01

    Objectives. We assessed public and smoker support for enacted and potential point-of-sale (POS) tobacco-control policies under the Family Smoking Prevention and Tobacco Control Act. Methods. We surveyed a US nationally representative sample of 17 507 respondents (6595 smokers) in January through February 2013, and used linear regression to calculate weighted point estimates and identify factors associated with support for POS policies among adults and smokers. Results. Overall, nonsmokers were more supportive than were smokers. Regardless of smoking status, African Americans, Hispanics, women, and those of older ages were more supportive than White, male, and younger respondents, respectively. Policy support varied by provision. More than 80% of respondents supported minors’ access restrictions and more than 45% supported graphic warnings. Support was lowest for plain packaging (23%), black-and-white advertising (26%), and a ban on menthol cigarettes (36%). Conclusions. Public support for marketing and POS provisions is low relative to other areas of tobacco control. Tobacco-control advocates and the Food and Drug Administration should build on existing levels of public support to promote and maintain evidence-based, but controversial, policy changes in the retail environment. PMID:26270303

  11. Line-of-sight kinematics for a two-axis head mirror: equations for predicting and controlling mirrored LOS pointing

    NASA Astrophysics Data System (ADS)

    Royalty, James M. B.

    2009-05-01

    Gimbaled planar mirrors are used to point and stabilize a camera's or laser's line-ofsight (LOS). The mirror with its reflection property adds another degree of complexity to the already complex area of LOS pointing and stabilization modeling and control. For example, when the optics and detector are located off gimbal and utilizing a 2-axis gimbaled mirror to point the LOS, the image at the detector rolls one for one with the outer gimbal rotation. This is difficult to understand unless the equations are developed to show this. The LOS pointing kinematic equations for a planar gimbaled mirror begin with the mirror reflectance equation [2,3]. This equation describes the reflected ray or vector in terms of the incoming ray and the mirror unit normal, and ultimately creates the mathematical relationship between the reflected ray, the base (or a user-defined reference frame), and the detector reference frame. This kinematic relationship is differentiated to form the LOS rate equations from which one can easily see what states are necessary, and how these states are combined, for inertially stabilizing the LOS about its roll, pitch, and yaw axes.

  12. Prevention of Relapse and Recurrence in Adults with Major Depressive Disorder: Systematic Review and Meta-Analyses of Controlled Trials

    PubMed Central

    Lau, Wai Keat; Sim, Jordan; Sum, Min Yi; Baldessarini, Ross J.

    2016-01-01

    Background: Findings of substantial remaining morbidity in treated major depressive disorder (MDD) led us to review controlled trials of treatments aimed at preventing early relapses or later recurrences in adults diagnosed with MDD to summarize available data and to guide further research. Methods: Reports (n = 97) were identified through systematic, computerized literature searching up to February 2015. Treatment versus control outcomes were summarized by random-effects meta-analyses. Results: In 45 reports of 72 trials (n = 14 450 subjects) lasting 33.4 weeks, antidepressants were more effective than placebos in preventing relapses (response rates [RR] = 1.90, confidence interval [CI]: 1.73–2.08; NNT = 4.4; p < 0.0001). In 35 reports of 37 trials (n = 7253) lasting 27.0 months, antidepressants were effective in preventing recurrences (RR = 2.03, CI 1.80–2.28; NNT = 3.8; p < 0.0001), with minor differences among drug types. In 17 reports of 22 trials (n = 1 969) lasting 23.7 months, psychosocial interventions yielded inconsistent or inconclusive results. Conclusions: Despite evidence of the efficacy of drug treatment compared to placebos or other controls, the findings further underscore the substantial, unresolved morbidity in treated MDD patients and strongly encourage further evaluations of specific, improved individual and combination therapies (pharmacological and psychological) conducted over longer times, as well as identifying clinical predictors of positive or unfavorable responses and of intolerability of long-term treatments in MDD. PMID:26152228

  13. The Effect of Abdominal Support on Functional Outcomes in Patients Following Major Abdominal Surgery: A Randomized Controlled Trial

    PubMed Central

    Cheifetz, Oren; Overend, Tom J.; Crowe, Jean

    2010-01-01

    ABSTRACT Purpose: Immobility and pain are modifiable risk factors for development of venous thromboembolism and pulmonary morbidity after major abdominal surgery (MAS). The purpose of this study was to investigate the effect of abdominal incision support with an elasticized abdominal binder on postoperative walk performance (mobility), perceived distress, pain, and pulmonary function in patients following MAS. Methods: Seventy-five patients scheduled to undergo MAS via laparotomy were randomized to experimental (binder) or control (no binder) groups. Sixty (33 male, 27 female; mean age 58±14.9 years) completed the study. Preoperative measurements of 6-minute walk test (6MWT) distance, perceived distress, pain, and pulmonary function were repeated 1, 3, and 5 days after surgery. Results: Surgery was associated with marked postoperative reductions (p<0.001) in walk distance (∼75–78%, day 3) and forced vital capacity (35%, all days) for both groups. Improved 6MWT distance by day 5 was greater (p<0.05) for patients wearing a binder (80%) than for the control group (48%). Pain and symptom-associated distress remained unchanged following surgery with binder usage, increasing significantly (p<0.05) only in the no binder group. Conclusion: Elasticized abdominal binders provide a non-invasive intervention for enhancing recovery of walk performance, controlling pain and distress, and improving patients' experience following MAS. PMID:21629603

  14. Population and forensic genetic analyses of mitochondrial DNA control region variation from six major provinces in the Korean population.

    PubMed

    Hong, Seung Beom; Kim, Ki Cheol; Kim, Wook

    2015-07-01

    We generated complete mitochondrial DNA (mtDNA) control region sequences from 704 unrelated individuals residing in six major provinces in Korea. In addition to our earlier survey of the distribution of mtDNA haplogroup variation, a total of 560 different haplotypes characterized by 271 polymorphic sites were identified, of which 473 haplotypes were unique. The gene diversity and random match probability were 0.9989 and 0.0025, respectively. According to the pairwise comparison of the 704 control region sequences, the mean number of pairwise differences between individuals was 13.47±6.06. Based on the result of mtDNA control region sequences, pairwise FST genetic distances revealed genetic homogeneity of the Korean provinces on a peninsular level, except in samples from Jeju Island. This result indicates there may be a need to formulate a local mtDNA database for Jeju Island, to avoid bias in forensic parameter estimates caused by genetic heterogeneity of the population. Thus, the present data may help not only in personal identification but also in determining maternal lineages to provide an expanded and reliable Korean mtDNA database. These data will be available on the EMPOP database via accession number EMP00661.

  15. AKT3 controls mitochondrial biogenesis and autophagy via regulation of the major nuclear export protein CRM-1.

    PubMed

    Corum, Daniel G; Tsichlis, Philip N; Muise-Helmericks, Robin C

    2014-01-01

    Our previous work has shown that Akt3 is required for mitochondrial biogenesis in primary human endothelial cells (ECs) and in Akt3-null mice; Akt3 affects subcellular localization of peroxisome proliferator-activated receptor γ coactivator-1 (PGC-1α), the master regulator of mitochondrial biogenesis. The purpose of this study is to determine the mechanism by which Akt3 controls the subcellular distribution of PGC-1α and to explore the effect on mitochondrial biogenesis and turnover during angiogenesis. Here we use standard biochemical analyses and Akt3-knockdown strategies to show that Akt3 controls the stabilization of chromosome maintenance region-1 (CRM-1), the major nuclear export receptor. Site-directed mutagenesis and association analyses show that PGC-1α nuclear export is CRM-1 dependent. Akt3 knockdown and CRM-1 overexpression cause 3-fold reductions in PGC-1α target gene expression, compared to control levels. Akt3 inhibition causes autophagy, as measured by autophagosome formation, in a CRM-1-dependent, Akt1/mTOR-independent pathway. In vivo, Akt3-null and heterozygous mice show dose-dependent decreases in angiogenesis compared to wild-type littermates (~5- and 2.5-fold decreases, respectively), as assessed by Matrigel plug assays. This correlates with an ~1.5-fold decrease in mitochondrial Cox IV expression. Our studies suggest that Akt3 is a regulator of mitochondrial dynamics in the vasculature via regulation of CRM-1-dependent nuclear export.

  16. Independent walking as a major skill for the development of anticipatory postural control: evidence from adjustments to predictable perturbations.

    PubMed

    Cignetti, Fabien; Zedka, Milan; Vaugoyeau, Marianne; Assaiante, Christine

    2013-01-01

    Although there is suggestive evidence that a link exists between independent walking and the ability to establish anticipatory strategy to stabilize posture, the extent to which this skill facilitates the development of anticipatory postural control remains largely unknown. Here, we examined the role of independent walking on the infants' ability to anticipate predictable external perturbations. Non-walking infants, walking infants and adults were sitting on a platform that produced continuous rotation in the frontal plane. Surface electromyography (EMG) of neck and lower back muscles and the positions of markers located on the platform, the upper body and the head were recorded. Results from cross-correlation analysis between rectified and filtered EMGs and platform movement indicated that although muscle activation already occurred before platform movement in non-walking infants, only walking infants demonstrated an adult-like ability for anticipation. Moreover, results from further cross-correlation analysis between segmental angular displacement and platform movement together with measures of balance control at the end-points of rotation of the platform evidenced two sorts of behaviour. The adults behaved as a non-rigid non-inverted pendulum, rather stabilizing head in space, while both the walking and non-walking infants followed the platform, behaving as a rigid inverted pendulum. These results suggest that the acquisition of independent walking plays a role in the development of anticipatory postural control, likely improving the internal model for the sensorimotor control of posture. However, despite such improvement, integrating the dynamics of an external object, here the platform, within the model to maintain balance still remains challenging in infants.

  17. Independent Walking as a Major Skill for the Development of Anticipatory Postural Control: Evidence from Adjustments to Predictable Perturbations

    PubMed Central

    Cignetti, Fabien; Zedka, Milan; Vaugoyeau, Marianne; Assaiante, Christine

    2013-01-01

    Although there is suggestive evidence that a link exists between independent walking and the ability to establish anticipatory strategy to stabilize posture, the extent to which this skill facilitates the development of anticipatory postural control remains largely unknown. Here, we examined the role of independent walking on the infants’ ability to anticipate predictable external perturbations. Non-walking infants, walking infants and adults were sitting on a platform that produced continuous rotation in the frontal plane. Surface electromyography (EMG) of neck and lower back muscles and the positions of markers located on the platform, the upper body and the head were recorded. Results from cross-correlation analysis between rectified and filtered EMGs and platform movement indicated that although muscle activation already occurred before platform movement in non-walking infants, only walking infants demonstrated an adult-like ability for anticipation. Moreover, results from further cross-correlation analysis between segmental angular displacement and platform movement together with measures of balance control at the end-points of rotation of the platform evidenced two sorts of behaviour. The adults behaved as a non-rigid non-inverted pendulum, rather stabilizing head in space, while both the walking and non-walking infants followed the platform, behaving as a rigid inverted pendulum. These results suggest that the acquisition of independent walking plays a role in the development of anticipatory postural control, likely improving the internal model for the sensorimotor control of posture. However, despite such improvement, integrating the dynamics of an external object, here the platform, within the model to maintain balance still remains challenging in infants. PMID:23409171

  18. Design of set-point weighting PI{sup λ} + D{sup μ} controller for vertical magnetic flux controller in Damavand tokamak

    SciTech Connect

    Rasouli, H.; Fatehi, A.

    2014-12-15

    In this paper, a simple method is presented for tuning weighted PI{sup λ} + D{sup μ} controller parameters based on the pole placement controller of pseudo-second-order fractional systems. One of the advantages of this controller is capability of reducing the disturbance effects and improving response to input, simultaneously. In the following sections, the performance of this controller is evaluated experimentally to control the vertical magnetic flux in Damavand tokamak. For this work, at first a fractional order model is identified using output-error technique in time domain. For various practical experiments, having desired time responses for magnetic flux in Damavand tokamak, is vital. To approach this, at first the desired closed loop reference models are obtained based on generalized characteristic ratio assignment method in fractional order systems. After that, for the identified model, a set-point weighting PI{sup λ} + D{sup μ} controller is designed and simulated. Finally, this controller is implemented on digital signal processor control system of the plant to fast/slow control of magnetic flux. The practical results show appropriate performance of this controller.

  19. Robust control chart for change point detection of process variance in the presence of disturbances

    NASA Astrophysics Data System (ADS)

    Huat, Ng Kooi; Midi, Habshah

    2015-02-01

    A conventional control chart for detecting shifts in variance of a process is typically developed where in most circumstances the nominal value of variance is unknown and based upon one of the essential assumptions that the underlying distribution of the quality characteristic is normal. However, this is not always the case as it is fairly evident that the statistical estimates used for these charts are very sensitive to the occurrence of occasional outliers. This is for the reason that the robust control charts are put forward when the underlying normality assumption is not met, and served as a remedial measure to the problem of contamination in process data. Realizing that the existing approach, namely Biweight A pooled residuals method, appears to be resistance to localized disturbances but lack of efficiency when there are diffuse disturbances. To be concrete, diffuse disturbances are those that have equal change of being perturbed by any observation, while a localized disturbance will have effect on every member of a certain subsample or subsamples. Since the efficiency of estimators in the presence of disturbances can rely heavily upon whether the disturbances are distributed throughout the observations or concentrated in a few subsamples. Hence, to this end, in this paper we proposed a new robust MBAS control chart by means of subsample-based robust Modified Biweight A scale estimator in estimating the process standard deviation. It has strong resistance to both localized and diffuse disturbances as well as high efficiency when no disturbances are present. The performance of the proposed robust chart was evaluated based on some decision criteria through Monte Carlo simulation study.

  20. The dynamics and control of large flexible space structures, 3. Part A: Shape and orientation control of a platform in orbit using point actuators

    NASA Technical Reports Server (NTRS)

    Bainum, P. M.; Reddy, A. S. S. R.; Krishna, R.; James, P. K.

    1980-01-01

    The dynamics, attitude, and shape control of a large thin flexible square platform in orbit are studied. Attitude and shape control are assumed to result from actuators placed perpendicular to the main surface and one edge and their effect on the rigid body and elastic modes is modelled to first order. The equations of motion are linearized about three different nominal orientations: (1) the platform following the local vertical with its major surface perpendicular to the orbital plane; (2) the platform following the local horizontal with its major surface normal to the local vertical; and (3) the platform following the local vertical with its major surface perpendicular to the orbit normal. The stability of the uncontrolled system is investigated analytically. Once controllability is established for a set of actuator locations, control law development is based on decoupling, pole placement, and linear optimal control theory. Frequencies and elastic modal shape functions are obtained using a finite element computer algorithm, two different approximate analytical methods, and the results of the three methods compared.

  1. Distribution of controlled substances in the U.S. supply chain: where does the compass point?

    PubMed

    Ruble, James H

    2012-09-01

    Recent administrative actions taken by the Drug Enforcement Administration (DEA) in Florida have prompted an articulate and detailed discussion of the pharmaceutical supply chain for controlled substances. Current practices in commercial distribution systems may have a partial nexus to the proliferation of opioid prescription drug abuse in Florida. No single factor or entity is responsible for this abuse proliferation, and there is no intent to harm consumers; however, distribution practices are adding risk to public health. This commentary extends a discussion on supply chain practices that seem misaligned in the promotion of legitimate business objectives and advancing public health.

  2. Space infrared telescope pointing control system. Infrared telescope tracking in the presence of target motion

    NASA Technical Reports Server (NTRS)

    Powell, J. D.; Schneider, J. B.

    1986-01-01

    The use of charge-coupled-devices, or CCD's, has been documented by a number of sources as an effective means of providing a measurement of spacecraft attitude with respect to the stars. A method exists of defocussing and interpolation of the resulting shape of a star image over a small subsection of a large CCD array. This yields an increase in the accuracy of the device by better than an order of magnitude over the case when the star image is focussed upon a single CCD pixel. This research examines the effect that image motion has upon the overall precision of this star sensor when applied to an orbiting infrared observatory. While CCD's collect energy within the visible spectrum of light, the targets of scientific interest may well have no appreciable visible emissions. Image motion has the effect of smearing the image of the star in the direction of motion during a particular sampling interval. The presence of image motion is incorporated into a Kalman filter for the system, and it is shown that the addition of a gyro command term is adequate to compensate for the effect of image motion in the measurement. The updated gyro model is included in this analysis, but has natural frequencies faster than the projected star tracker sample rate for dim stars. The system state equations are reduced by modelling gyro drift as a white noise process. There exists a tradeoff in selected star tracker sample time between the CCD, which has improved noise characteristics as sample time increases, and the gyro, which will potentially drift further between long attitude updates. A sample time which minimizes pointing estimation error exists for the random drift gyro model as well as for a random walk gyro model.

  3. A central swivel point in the RFC clamp loader controls PCNA opening and loading on DNA.

    PubMed

    Sakato, Miho; O'Donnell, Mike; Hingorani, Manju M

    2012-02-17

    Replication factor C (RFC) is a five-subunit complex that loads proliferating cell nuclear antigen (PCNA) clamps onto primer-template DNA (ptDNA) during replication. RFC subunits belong to the AAA(+) superfamily, and their ATPase activity drives interactions between the clamp loader, the clamp, and the ptDNA, leading to topologically linked PCNA·ptDNA. We report the kinetics of transient events in Saccharomyces cerevisiae RFC-catalyzed PCNA loading, including ATP-induced RFC activation, PCNA opening, ptDNA binding, ATP hydrolysis, PCNA closing, and PCNA·ptDNA release. This detailed perspective enables assessment of individual RFC-A, RFC-B, RFC-C, RFC-D, and RFC-E subunit functions in the reaction mechanism. Functions have been ascribed to RFC subunits previously based on a steady-state analysis of 'arginine-finger' ATPase mutants; however, pre-steady-state analysis provides a different view. The central subunit RFC-C serves as a critical swivel point in the clamp loader. ATP binding to this subunit initiates RFC activation, and the clamp loader adopts a spiral conformation that stabilizes PCNA in a corresponding open spiral. The importance of RFC subunit response to ATP binding decreases as RFC-C>RFC-D>RFC-B, with RFC-A being unnecessary. RFC-C-dependent activation of RFC also enables ptDNA binding, leading to the formation of the RFC·ATP·PCNA(open)·ptDNA complex. Subsequent ATP hydrolysis leads to complex dissociation, with RFC-D activity contributing the most to rapid ptDNA release. The pivotal role of the RFC-B/C/D subunit ATPase core in clamp loading is consistent with the similar central location of all three ATPase active subunits of the Escherichia coli clamp loader.

  4. Robust stability analysis and dynamic gain-scheduled controller design for point time-delay systems with parametrical uncertainties

    NASA Astrophysics Data System (ADS)

    De la Sen, M.

    2008-08-01

    This paper discusses linear fractional representations (LFR) of parameter-dependent nonlinear systems with real-rational nonlinearities and point-delayed dynamics. Sufficient conditions for robust global asymptotic stability independent of the delays and the existence of a robust stabilizing gain-scheduled dynamic controller are investigated via linear matrix inequalities. Such inequalities are obtained from the values of the time-derivatives of appropriate Lyapunov functions at all the vertices of the polytope which contains the parametrized uncertainties. The synthesized stabilizing controller consists of an interpolation being performed with the stabilizing controllers at the set of vertices of a certain polytope where the nonlinear-rational parametrization belongs to. Some extensions are also given concerning robust global asymptotic stability dependent of the delays. Numerical examples corroborate the usefulness of the proposed formalism and its applicability to practical related problems.

  5. Randomized Controlled Trials and real life studies. Approaches and methodologies: a clinical point of view.

    PubMed

    Saturni, S; Bellini, F; Braido, F; Paggiaro, P; Sanduzzi, A; Scichilone, N; Santus, P A; Morandi, L; Papi, A

    2014-04-01

    Randomized Controlled Trials (RCTs) are the "gold standard" for evaluating treatment outcomes providing information on treatments "efficacy". They are designed to test a therapeutic hypothesis under optimal setting in the absence of confounding factors. For this reason they have high internal validity. The strict and controlled conditions in which they are conducted, leads to low generalizability because they are performed in conditions very different from real life usual care. Conversely, real life studies inform on the "effectiveness" of a treatment, that is, the measure of the extent to which an intervention does what is intended to do in routine circumstances. At variance to RCTs, real life trials have high generalizability, but low internal validity. Recently the number of real life studies has been rapidly growing in different areas of respiratory medicine, particularly in asthma and COPD. The role of such studies is becoming a hot topic in respiratory medicine, attracting research interest and debate. In the first part of this review we discuss some of the advantages and disadvantages of different types of RCTs and analyze the strengths and weaknesses of real life trials, considering the recent examples of some studies conducted in COPD. We then discuss methodological approaches and options to overcome some of the limitations of real life studies. Comparing the conclusions of effectiveness and efficacy trials can provide important pieces of information. Indeed, these approaches can result complementary, and they can guide the interpretation of each other results.

  6. Vertical Field of View Reference Point Study for Flight Path Control and Hazard Avoidance

    NASA Technical Reports Server (NTRS)

    Comstock, J. Raymond, Jr.; Rudisill, Marianne; Kramer, Lynda J.; Busquets, Anthony M.

    2002-01-01

    Researchers within the eXternal Visibility System (XVS) element of the High-Speed Research (HSR) program developed and evaluated display concepts that will provide the flight crew of the proposed High-Speed Civil Transport (HSCT) with integrated imagery and symbology to permit path control and hazard avoidance functions while maintaining required situation awareness. The challenge of the XVS program is to develop concepts that would permit a no-nose-droop configuration of an HSCT and expanded low visibility HSCT operational capabilities. This study was one of a series of experiments exploring the 'design space' restrictions for physical placement of an XVS display. The primary experimental issues here was 'conformality' of the forward display vertical position with respect to the side window in simulated flight. 'Conformality' refers to the case such that the horizon and objects appear in the same relative positions when viewed through the forward windows or display and the side windows. This study quantified the effects of visual conformality on pilot flight path control and hazard avoidance performance. Here, conformality related to the positioning and relationship of the artificial horizon line and associated symbology presented on the forward display and the horizon and associated ground, horizon, and sky textures as they would appear in the real view through a window presented in the side window display. No significant performance consequences were found for the non-conformal conditions.

  7. Loop Heat Pipe Transient Behavior Using Heat Source Temperature for Set Point Control with Thermoelectric Converter on Reservoir

    NASA Technical Reports Server (NTRS)

    Ku, Jentung; Paiva, Kleber; Mantelli, Marcia

    2011-01-01

    The LHP operating temperature is governed by the saturation temperature of its reservoir. Controlling the reservoir saturation temperature is commonly done by cold biasing the reservoir and using electrical heaters to provide the required control power. With this method, the loop operating temperature can be controlled within 0.5K or better. However, because the thermal resistance that exists between the heat source and the LHP evaporator, the heat source temperature will vary with its heat output even if the LHP operating temperature is kept constant. Since maintaining a constant heat source temperature is of most interest, a question often raised is whether the heat source temperature can be used for LHP set point temperature control. A test program with a miniature LHP was carried out to investigate the effects on the LHP operation when the control temperature sensor was placed on the heat source instead of the reservoir. In these tests, the LHP reservoir was cold-biased and was heated by a control heater. Test results show that it was feasible to use the heat source temperature for feedback control of the LHP operation. In particular, when a thermoelectric converter was used as the reservoir control heater, the heat source temperature could be maintained within a tight range using a proportional-integral-derivative or on/off control algorithm. Moreover, because the TEC could provide both heating and cooling to the reservoir, temperature oscillations during fast transients such as loop startup could be eliminated or substantially reduced when compared to using an electrical heater as the control heater.

  8. A conserved RpoS-dependent small RNA controls the synthesis of major porin OmpD

    PubMed Central

    Fröhlich, Kathrin S.; Papenfort, Kai; Berger, Allison A.; Vogel, Jörg

    2012-01-01

    A remarkable feature of many small non-coding RNAs (sRNAs) of Escherichia coli and Salmonella is their accumulation in the stationary phase of bacterial growth. Several stress response regulators and sigma factors have been reported to direct the transcription of stationary phase-specific sRNAs, but a widely conserved sRNA gene that is controlled by the major stationary phase and stress sigma factor, σS (RpoS), has remained elusive. We have studied in Salmonella the conserved SdsR sRNA, previously known as RyeB, one of the most abundant stationary phase-specific sRNAs in E. coli. Alignments of the sdsR promoter region and genetic analysis strongly suggest that this sRNA gene is selectively transcribed by σS. We show that SdsR down-regulates the synthesis of the major Salmonella porin OmpD by Hfq-dependent base pairing; SdsR thus represents the fourth sRNA to regulate this major outer membrane porin. Similar to the InvR, MicC and RybB sRNAs, SdsR recognizes the ompD mRNA in the coding sequence, suggesting that this mRNA may be primarily targeted downstream of the start codon. The SdsR-binding site in ompD was localized by 3′-RACE, an experimental approach that promises to be of use in predicting other sRNA–target interactions in bacteria. PMID:22180532

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

    PubMed Central

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

    2016-01-01

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

  10. Regional cerebral blood flow in mood disorders. I. Comparison of major depressives and normal controls at rest

    SciTech Connect

    Sackeim, H.A.; Prohovnik, I.; Moeller, J.R.; Brown, R.P.; Apter, S.; Prudic, J.; Devanand, D.P.; Mukherjee, S. )

    1990-01-01

    We measured regional cerebral blood flow with the xenon 133 inhalation technique in 41 patients with major depressive disorder and 40 matched, normal controls during an eyes-closed, resting condition. The depressed group had a marked reduction in global cortical blood flow. To examine topographic abnormalities, traditional multivariate analyses were applied, as well as a new scaled subprofile model developed to identify abnormal functional neural networks in clinical samples. Both approaches indicated that the depressed sample had an abnormality in topographic distribution of blood flow, in addition to the global deficit. The scaled subprofile model identified the topographic abnormality as being due to flow reduction in the depressed patients in selective frontal, central, superior temporal, and anterior parietal regions. This pattern may reflect dysfunction in the parallel distributed cortical network involving frontal and temporoparietal polymodal association areas. The extent of this topographic abnormality, as revealed by the scaled subprofile model, was associated with both patient age and severity of depressive symptoms.

  11. Attachment as moderator of treatment outcome in major depression: a randomized control trial of interpersonal psychotherapy versus cognitive behavior therapy.

    PubMed

    McBride, Carolina; Atkinson, Leslie; Quilty, Lena C; Bagby, R Michael

    2006-12-01

    Anxiety and avoidance dimensions of adult attachment insecurity were tested as moderators of treatment outcome for interpersonal psychotherapy (IPT) and cognitive- behavioral therapy (CBT). Fifty-six participants with major depression were randomly assigned to these treatment conditions. Beck Depression Inventory--II, Six-Item Hamilton Rating Scale for Depression scores, and remission status served as outcome measures. Patients higher on attachment avoidance showed significantly greater reduction in depression severity and greater likelihood of symptom remission with CBT as compared with IPT, even after controlling for obsessive-compulsive and avoidant personality disorder symptoms. Results were replicated across treatment completers and intent-to-treat samples. These results suggest that it is important to consider the interaction between attachment insecurity and treatment type when comparing efficacy of treatments.

  12. Major quantitative trait loci control divergence in critical photoperiod for flowering between selfing and outcrossing species of monkeyflower (Mimulus).

    PubMed

    Fishman, Lila; Sweigart, Andrea L; Kenney, Amanda M; Campbell, Samantha

    2014-03-01

    • Divergence in flowering time is a key contributor to reproductive isolation between incipient species, as it enforces habitat specialization and causes assortative mating even in sympatry. Understanding the genetic basis of flowering time divergence illuminates the origins and maintenance of species barriers. • We investigated the genetics of divergence in critical photoperiod for flowering between yellow monkeyflowers Mimulus guttatus (outcrosser, summer flowering) and Mimulus nasutus (selfer, spring flowering). We used quantitative trait locus (QTL) mapping of F2 hybrids and fine-mapping in nearly isogenic lines to characterize the genomic regions underlying a > 2 h critical photoperiod difference between allopatric populations, and then tested whether the same QTLs control flowering time in sympatry. • We identified two major QTLs that almost completely explain M. nasutus's ability to flower in early spring; they are shared by allopatric and sympatric population pairs. The smaller QTL is coincident with one that differentiates ecotypes within M. guttatus, but the larger effect QTL appears unique to M. nasutus. • Unlike floral traits associated with mating system divergence, large interspecific differences in flowering phenology depend on only a few loci. Major critical photoperiod QTLs may be 'speciation genes' and also restrict interspecific gene flow in secondary sympatry.

  13. A new method to obtain ground control points based on SRTM data

    NASA Astrophysics Data System (ADS)

    Wang, Pu; An, Wei; Deng, Xin-pu; Zhang, Xi

    2013-09-01

    The GCPs are widely used in remote sense image registration and geometric correction. Normally, the DRG and DOM are the major data source from which GCPs are extracted. But the high accuracy products of DRG and DOM are usually costly to obtain. Some of the production are free, yet without any guarantee. In order to balance the cost and the accuracy, the paper proposes a method of extracting the GCPs from SRTM data. The method consist of artificial assistance, binarization, data resample and reshape. With artificial assistance to find out which part of SRTM data could be used as GCPs, such as the islands or sharp coast line. By utilizing binarization algorithm , the shape information of the region is obtained while other information is excluded. Then the binary data is resampled to a suitable resolution required by specific application. At last, the data would be reshaped according to satellite imaging type to obtain the GCPs which could be used. There are three advantages of the method proposed in the paper. Firstly, the method is easy for implementation. Unlike the DRG data or DOM data that charges a lot, the SRTM data is totally free to access without any constricts. Secondly, the SRTM has a high accuracy about 90m that is promised by its producer, so the GCPs got from it can also obtain a high quality. Finally, given the SRTM data covers nearly all the land surface of earth between latitude -60° and latitude +60°, the GCPs which are produced by the method can cover most important regions of the world. The method which obtain GCPs from SRTM data can be used in meteorological satellite image or some situation alike, which have a relative low requirement about the accuracy. Through plenty of simulation test, the method is proved convenient and effective.

  14. Low intensity vs. self-guided Internet-delivered psychotherapy for major depression: a multicenter, controlled, randomized study

    PubMed Central

    2013-01-01

    Background Major depression will become the second most important cause of disability in 2020. Computerized cognitive-behaviour therapy could be an efficacious and cost-effective option for its treatment. No studies on cost-effectiveness of low intensity vs self-guided psychotherapy has been carried out. The aim of this study is to assess the efficacy of low intensity vs self-guided psychotherapy for major depression in the Spanish health system. Methods The study is made up of 3 phases: 1.- Development of a computerized cognitive-behaviour therapy for depression tailored to Spanish health system. 2.- Multicenter controlled, randomized study: A sample (N=450 patients) with mild/moderate depression recruited in primary care. They should have internet availability at home, not receive any previous psychological treatment, and not suffer from any other severe somatic or psychological disorder. They will be allocated to one of 3 treatments: a) Low intensity Internet-delivered psychotherapy + improved treatment as usual (ITAU) by GP, b) Self-guided Internet-delivered psychotherapy + ITAU or c) ITAU. Patients will be diagnosed with MINI psychiatric interview. Main outcome variable will be Beck Depression Inventory. It will be also administered EuroQol 5D (quality of life) and Client Service Receipt Inventory (consume of health and social services). Patients will be assessed at baseline, 3 and 12 months. An intention to treat and a per protocol analysis will be performed. Discussion The comparisons between low intensity and self-guided are infrequent, and also a comparative economic evaluation between them and compared with usual treatment in primary. The strength of the study is that it is a multicenter, randomized, controlled trial of low intensity and self-guided Internet-delivered psychotherapy for depression in primary care, being the treatment completely integrated in primary care setting. Trial registration Clinical Trials NCT01611818 PMID:23312003

  15. Human cortical control of hand movements: parietofrontal networks for reaching, grasping, and pointing.

    PubMed

    Filimon, Flavia

    2010-08-01

    In primates, control of the limb depends on many cortical areas. Whereas specialized parietofrontal circuits have been proposed for different movements in macaques, functional neuroimaging in humans has revealed widespread, overlapping activations for hand and eye movements and for movements such as reaching and grasping. This review examines the involvement of frontal and parietal areas in hand and arm movements in humans as revealed with functional neuroimaging. The degree of functional specialization, possible homologies with macaque cortical regions, and differences between frontal and posterior parietal areas are discussed, as well as a possible organization of hand movements with respect to different spatial reference frames. The available evidence supports a cortical organization along gradients of sensory (visual to somatosensory) and effector (eye to hand) preferences.

  16. Control of the point defects in oxide materials to enhance functionalities in imaging

    NASA Astrophysics Data System (ADS)

    Viana, B.; Maldiney, Th.; Blahuta, S.; Béssière, A.; Gourier, D.; Richard, C.; Scherman, D.; Ouspenski, V.

    2013-03-01

    Last generation medical imaging equipments require materials which possess outstanding performances. For scintillators in the high energy imaging field (PET), crystals with high light yields allow a decrease of the irradiation dose received by the patients during medical application and a more accurate diagnostic. Thermally stimulated luminescence (TSL) data provides the depth of hole or electron traps which can limit the efficiency and increase the kinetic. If these traps are due to lanthanide ions, the level schemes can predict the depth values. Thanks to comparison between TSL glow curves and energy diagrams, the traps inside oxide-based-hosts can be identified. Two examples are proposed here, first, the scintillation in the Ce:LYSO crystals which can be improved by thermal annealing and where divalent cations are used for charge compensation and traps removal and second, optical imaging using a new approach where persistent luminescent nanoparticles are used for in-vivo imaging. In both cases, traps depth should be carefully controlled.

  17. Cell-specific localization of Na+ in roots of durum wheat and possible control points for salt exclusion.

    PubMed

    Läuchli, André; James, Richard A; Huang, Cheng X; McCully, Margaret; Munns, Rana

    2008-11-01

    Sodium exclusion from leaves is an important mechanism for salt tolerance in durum wheat. To characterize possible control points for Na(+) exclusion, quantitative cryo-analytical scanning electron microscopy was used to determine cell-specific ion profiles across roots of two durum wheat genotypes with contrasting rates of Na(+) transport from root to shoot grown in 50 mm NaCl. The Na(+) concentration in Line 149 (low transport genotype) declined across the cortex, being highest in the epidermal and sub-epidermal cells (48 mm) and lowest in the inner cortical cells (22 mm). Na(+) was high in the pericycle (85 mm) and low in the xylem parenchyma (34 mm). The Na(+) profile in Tamaroi (high transport genotype) had a similar trend but with a high concentration (130 mm) in the xylem parenchyma. The K(+) profiles were generally inverse to those of Na(+). Chloride was only detected in the epidermis. These data suggest that the epidermal and cortical cells removed most of the Na(+) and Cl(-) from the transpiration stream before it reached the endodermis, and that the endodermis is not the control point for salt uptake by the plant. The pericycle as well as the xylem parenchyma may be important in the control of net Na(+) loading of the xylem.

  18. Hazard analysis of critical control points assessment as a tool to respond to emerging infectious disease outbreaks.

    PubMed

    Edmunds, Kelly L; Hunter, Paul R; Few, Roger; Bell, Diana J

    2013-01-01

    Highly pathogenic avian influenza virus (HPAI) strain H5N1 has had direct and indirect economic impacts arising from direct mortality and control programmes in over 50 countries reporting poultry outbreaks. HPAI H5N1 is now reported as the most widespread and expensive zoonotic disease recorded and continues to pose a global health threat. The aim of this research was to assess the potential of utilising Hazard Analysis of Critical Control Points (HACCP) assessments in providing a framework for a rapid response to emerging infectious disease outbreaks. This novel approach applies a scientific process, widely used in food production systems, to assess risks related to a specific emerging health threat within a known zoonotic disease hotspot. We conducted a HACCP assessment for HPAI viruses within Vietnam's domestic poultry trade and relate our findings to the existing literature. Our HACCP assessment identified poultry flock isolation, transportation, slaughter, preparation and consumption as critical control points for Vietnam's domestic poultry trade. Introduction of the preventative measures highlighted through this HACCP evaluation would reduce the risks posed by HPAI viruses and pressure on the national economy. We conclude that this HACCP assessment provides compelling evidence for the future potential that HACCP analyses could play in initiating a rapid response to emerging infectious diseases.

  19. Development of hazard analysis by critical control points (HACCP) procedures to control organic chemical hazards in the agricultural production of raw food commodities.

    PubMed

    Ropkins, Karl; Ferguson, Andrew; Beck, Angus J

    2003-01-01

    Hazard Analysis by Critical Control Points (HACCP) is a systematic approach to the identification, assessment, and control of hazards in the food chain. Effective HACCP requires the consideration of all chemical microbiological, and physical hazards. However, current procedures focus primarily on microbiological and physical hazards, while chemical aspects of HACCP have received relatively little attention. In this article we discuss the application of HACCP to organic chemical contaminants and the problems that are likely to be encountered in agriculture. We also present generic templates for the development of organic chemical contaminant HACCP procedures for selected raw food commodities, that is, cereal crops,raw meats, and milk.

  20. Access point analysis: what do adolescents in South Africa say about tobacco control programmes?

    PubMed

    Swart, Dehran; Panday, Saadhna; Reddy, S Priscilla; Bergström, Erik; de Vries, Hein

    2006-06-01

    This paper explores adolescent preferences for the setting, timing, delivery format, provider and key elements of tobacco control programmes. The need for programme sensitivity towards urban/rural, gender and ethnic subgroups is also discussed. Schools were purposively selected from the Southern Cape-Karoo Region, South Africa. Twelve prevention and nine cessation focus group discussions were conducted with Grade 6-8 students and Grade 8-9 smokers and ex-smokers, respectively. Adolescents reported similar preferences for prevention and cessation programmes. Although they were unaware of smoking prevention or cessation programmes, they reported a willingness to participate in such programmes. Programmes should include school-based activities that are supported by out-of-school activities held over weekends and holidays. Non-judgemental and empathetic teachers and peers, as well as ex-smokers were preferred as programme providers. School-based participatory delivery formats should be supported by community-based mass media approaches. Programmes can be jointly presented to boys and girls of diverse ethnic backgrounds with some gender-sensitive sessions. Programme participation and sustainability would be enhanced if it were exciting, fun filled and integrated into their daily lives. School-based programmes must be embedded within comprehensive approaches that involve community- and policy-level interventions.