Science.gov

Sample records for 600h hybrid synergy

  1. Evaluation of the 2008 Lexus LS 600H Hybrid Synergy Drive System

    SciTech Connect

    Burress, T.A.; Coomer, C.L.; Campbell, S.L.; Wereszczak, A.A.; Cunningham, J.P.; Marlino, L.D.; Seiber, L.E.; Lin, H.T.

    2009-01-15

    Subsystems of the 2008 Lexus 600h hybrid electric vehicle (HEV) were studied and tested as part of an intensive benchmarking effort carried out to produce detailed information concerning the current state of nondomestic alternative vehicle technologies. Feedback provided by benchmarking efforts is particularly useful to partners of the Vehicle Technologies collaborative research program as it is essential in establishing reasonable yet challenging programmatic goals which facilitate development of competitive technologies. The competitive nature set forth by the Vehicle Technologies program not only promotes energy independence and economic stability, it also advocates the advancement of alternative vehicle technologies in an overall global perspective. These technologies greatly facilitate the potential to reduce dependency on depleting natural resources and mitigate harmful impacts of transportation upon the environment.

  2. A Muscle Synergy-Inspired Adaptive Control Scheme for a Hybrid Walking Neuroprosthesis

    PubMed Central

    Alibeji, Naji A.; Kirsch, Nicholas Andrew; Sharma, Nitin

    2015-01-01

    A hybrid neuroprosthesis that uses an electric motor-based wearable exoskeleton and functional electrical stimulation (FES) has a promising potential to restore walking in persons with paraplegia. A hybrid actuation structure introduces effector redundancy, making its automatic control a challenging task because multiple muscles and additional electric motor need to be coordinated. Inspired by the muscle synergy principle, we designed a low dimensional controller to control multiple effectors: FES of multiple muscles and electric motors. The resulting control system may be less complex and easier to control. To obtain the muscle synergy-inspired low dimensional control, a subject-specific gait model was optimized to compute optimal control signals for the multiple effectors. The optimal control signals were then dimensionally reduced by using principal component analysis to extract synergies. Then, an adaptive feedforward controller with an update law for the synergy activation was designed. In addition, feedback control was used to provide stability and robustness to the control design. The adaptive-feedforward and feedback control structure makes the low dimensional controller more robust to disturbances and variations in the model parameters and may help to compensate for other time-varying phenomena (e.g., muscle fatigue). This is proven by using a Lyapunov stability analysis, which yielded semi-global uniformly ultimately bounded tracking. Computer simulations were performed to test the new controller on a 4-degree of freedom gait model. PMID:26734606

  3. Evaluation of the 2007 Toyota Camry Hybrid Synergy Drive System

    SciTech Connect

    Burress, T A; Coomer, C L; Campbell, S L; Seiber, L E; Marlino, L D; Staunton, R H; Cunningham, J P

    2008-04-15

    The U.S. Department of Energy (DOE) and American automotive manufacturers General Motors, Ford, and DaimlerChrysler began a five-year, cost-shared partnership in 1993. Currently, hybrid electric vehicle (HEV) research and development is conducted by DOE through its FreedomCAR and Vehicle Technologies (FCVT) program. The mission of the FCVT program is to develop more energy efficient and environmentally friendly highway transportation technologies. Program activities include research, development, demonstration, testing, technology validation, and technology transfer. These activities are aimed at developing technologies that can be domestically produced in a clean and cost-competitive manner. Under the FCVT program, support is provided through a three-phase approach [1] which is intended to: • Identify overall propulsion and vehicle-related needs by analyzing programmatic goals and reviewing industry’s recommendations and requirements, then develop the appropriate technical targets for systems, subsystems, and component research and development activities; • Develop and validate individual subsystems and components, including electric motors, emission control devices, battery systems, power electronics, accessories, and devices to reduce parasitic losses; and • Determine how well the components and subassemblies work together in a vehicle environment or as a complete propulsion system and whether the efficiency and performance targets at the vehicle level have been achieved. The research performed in this area will help remove technical and cost barriers to enable technology for use in such advanced vehicles as hybrid electric, plug-in hybrid electric, electric, and fuel-cell-powered vehicles.

  4. Evaluation of the 2010 Toyota Prius Hybrid Synergy Drive System

    SciTech Connect

    Burress, Timothy A; Campbell, Steven L; Coomer, Chester; Ayers, Curtis William; Wereszczak, Andrew A; Cunningham, Joseph Philip; Marlino, Laura D; Seiber, Larry Eugene; Lin, Hua-Tay

    2011-03-01

    Subsystems of the 2010 Toyota Prius hybrid electric vehicle (HEV) were studied and tested as part of an intensive benchmarking effort carried out to produce detailed information concerning the current state of nondomestic alternative vehicle technologies. Feedback provided by benchmarking efforts is particularly useful to partners of the Vehicle Technologies collaborative research program as it is essential in establishing reasonable yet challenging programmatic goals which facilitate development of competitive technologies. The competitive nature set forth by the Vehicle Technologies Program (VTP) not only promotes energy independence and economic stability, it also advocates the advancement of alternative vehicle technologies in an overall global perspective. These technologies greatly facilitate the potential to reduce dependency on depleting natural resources and mitigate harmful impacts of transportation upon the environment.

  5. Global hybrid forest mask: synergy of remote sensing, crowd sourcing and statistics

    NASA Astrophysics Data System (ADS)

    Shchepashchenko, D.; See, L. M.; Lesiv, M.; Fritz, S.; McCallum, I.; Shvidenko, A.; Kraxner, F.

    2013-12-01

    Many global and regional forest cover products have recently become available. The most advanced and comprehensive of these include the global land cover datasets (GLC2000, MODIS, GLOBCOVER), MODIS Vegetation Continuous Fields (VCF), LANDSAT based (e.g. Sexton et al., 2013) and radar based (e.g. Saatchi et al., 2010; Baccini et al., 2012; Santoro et al., 2012) products. However, they often contradict each other and are typically inconsistent with forest statistics. In particular, global land cover datasets contradict each other in many areas, have limited information about forest density and are not consistent with forest statistics. VCF most likely provides the most comprehensive information about forest density with a spatial resolution of 230m during 2000-2010. However when observing VCF dynamics for individual pixels, one can see variation that cannot be explained by forest cover dynamics, but instead by unstable pixel geometry and clouds. Landsat based products also suffer from cloud cover and cannot recognize sparse forest with canopy closure of 30% or less. Space-based radar is free from cloud, but still cannot reliably delineate areas as forest/non forest (Santoro, 2012). We compare all of the above mentioned remote sensing products with a sample of high resolution imagery provided by Google Earth. We have applied the crowd sourcing platform Geo-Wiki (Fritz et al., 2010, 2012) to collect 22K training points where the percentage of forest cover was estimated for a 1km pixel size. We applied the method of geographically weighted regression to calculate the map of probability of forest cover and the map of forest share. This involved the use of the Geo-Wiki training points in combination with the land cover products, MODIS VCF and LANDSAT. The synergy of remote sensing, statistics and crowd sourcing approaches was investigated to better understand the spatial distribution of forests. Both calibrated (using FAO FRA statistics) and non-calibrated ('best guess

  6. Optimized calculation of the synergy conditions between electron cyclotron current drive and lower hybrid current drive on EAST

    NASA Astrophysics Data System (ADS)

    Wei, Wei; Bo-Jiang, Ding; Y, Peysson; J, Decker; Miao-Hui, Li; Xin-Jun, Zhang; Xiao-Jie, Wang; Lei, Zhang

    2016-01-01

    The optimized synergy conditions between electron cyclotron current drive (ECCD) and lower hybrid current drive (LHCD) with normal parameters of the EAST tokamak are studied by using the C3PO/LUKE code based on the understanding of the synergy mechanisms so as to obtain a higher synergistic current and provide theoretical reference for the synergistic effect in the EAST experiment. The dependences of the synergistic effect on the parameters of two waves (lower hybrid wave (LHW) and electron cyclotron wave (ECW)), including the radial position of the power deposition, the power value of the LH and EC waves, and the parallel refractive indices of the LHW (N∥) are presented and discussed. Project supported by the National Magnetic Confinement Fusion Science Program of China (Grant Nos. 2011GB102000, 2012GB103000, and 2013GB106001), the National Natural Science Foundation of China (Grant Nos. 11175206 and 11305211), the JSPS-NRF-NSFC A3 Foresight Program in the Field of Plasma Physics (Grant No. 11261140328), and the Fundamental Research Funds for the Central Universities of China (Grant No. JZ2015HGBZ0472).

  7. Dependence of synergy current driven by lower hybrid wave and electron cyclotron wave on the frequency and parallel refractive index of electron cyclotron wave for Tokamaks

    SciTech Connect

    Huang, J.; Chen, S. Y. Tang, C. J.

    2014-01-15

    The physical mechanism of the synergy current driven by lower hybrid wave (LHW) and electron cyclotron wave (ECW) in tokamaks is investigated using theoretical analysis and simulation methods in the present paper. Research shows that the synergy relationship between the two waves in velocity space strongly depends on the frequency ω and parallel refractive index N{sub //} of ECW. For a given spectrum of LHW, the parameter range of ECW, in which the synergy current exists, can be predicted by theoretical analysis, and these results are consistent with the simulation results. It is shown that the synergy effect is mainly caused by the electrons accelerated by both ECW and LHW, and the acceleration of these electrons requires that there is overlap of the resonance regions of the two waves in velocity space.

  8. Investigation of Synergy Between Electrochemical Capacitors, Flywheels, and Batteries in Hybrid Energy Storage for PV Systems

    SciTech Connect

    Miller, John; Sibley, Lewis, B.; Wohlgemuth, John

    1999-06-01

    This report describes the results of a study that investigated the synergy between electrochemical capacitors (ECs) and flywheels, in combination with each other and with batteries, as energy storage subsystems in photovoltaic (PV) systems. EC and flywheel technologies are described and the potential advantages and disadvantages of each in PV energy storage subsystems are discussed. Seven applications for PV energy storage subsystems are described along with the potential market for each of these applications. A spreadsheet model, which used the net present value method, was used to analyze and compare the costs over time of various system configurations based on flywheel models. It appears that a synergistic relationship exists between ECS and flywheels. Further investigation is recommended to quantify the performance and economic tradeoffs of this synergy and its effect on overall system costs.

  9. [Gestalt synergy.].

    PubMed

    Carpentier, L

    1980-01-01

    The author describes a new psychotherapeutic approach called Gestalt Synergy. After presenting it's originality among others Body/Mind approaches, the author retraces the history of it's development through the personal history of the founder of Gestalt Synergy : Ilana Rubenfeld. Then follows an introduction of the Alexander Technique and the Feldenkrais Method which, with Gestalt, inspired Gestalt Synergy. The concepts and techniques of Gestalt Synergy are discussed and, the sequence of one session is illustrated. The author concludes on some personal changes noted from her use of this approach. PMID:17093697

  10. Professional Synergy.

    ERIC Educational Resources Information Center

    Harris, P. R.

    1981-01-01

    True professionals develop and create together a better future by their human endeavors in synergy. They must operate comfortably in two cultures--the industrial culture which is disappearing, and the superindustrial or cyberculture which is emerging. (CT)

  11. Prehension Synergies

    PubMed Central

    Zatsiorsky, Vladimir M.; Latash, Mark L.

    2010-01-01

    The precision grip requires the control of the normal and tangential forces exerted by the fingers as well as the control of the rotational equilibrium of the grasped object. Prehension synergies involve the conjoint changes in finger forces and moments during multifinger gripping tasks. Some of these adjustments are dictated by mechanics, whereas others are the result of a choice by the performer. PMID:15064652

  12. Compliant Synergies in Locomotion

    NASA Astrophysics Data System (ADS)

    Travers, Matthew; Choset, Howie; Goldman @ Georgia Tech. Physics Department Collaboration

    Biological systems appear to have natural mechanisms that allow them to readily compensate for unexpected environmental variations when compared to their mechanical (i.e., robotic) counterparts. We hypothesize that the basis for this discrepancy is almost innate: what biology appears to be born with, built-in mechanisms for coordinating their many degrees of freedom, we struggle to ``program.'' We therefore look toward biology for inspiration. In particular, we are interested in kinematic synergies, low-dimensional representations that explicitly encode the underlying structure of how systems coordinate their internal degrees of freedom to achieve high-level tasks. In this work, we derive parametric representations of kinematic synergies and present a new compliant locomotion control framework that enables the parameters to be directly controlled in response to external disturbances. We present results of this framework implemented on two separate platforms, a snake-like and hexapod robot. Our results show that, using synergies, the locomotion control of these very different systems can be reduced to simple, extremely capable, and common forms, thus offering new insights into both robotic as well as biological locomotion in complex terrains.

  13. From silos to synergy.

    PubMed

    Treadwell, Janet; Levermann, Laurie; Soffar, Gail; Giardino, Angelo

    2007-08-01

    Texas Children's Health Plan (TCHP) redesigned its approach to care management in an effort to provide support for member-centric care and the medical home. The changes in process and structure focused on connecting information and programs to promote care for members in a collaborative manner and taking advantage of the synergy between staff, programming, and the physician practices serving health plan membership. The results brought about an improvement in job satisfaction, positive change in the medical-loss ratio, and new innovations to support preventive and chronic care service delivery needs of the TCHP membership. PMID:18041351

  14. Synergy in satellite communication

    NASA Astrophysics Data System (ADS)

    Sachdev, D. K.

    1989-10-01

    After presenting a development history for satellite communications systems demonstrating the extent to which synergistic, efficiency-enhancing interactions between emerging technologies form the basis for much of the economic feasibility of these efforts, an evaluation is made of prospective synergisms. Among those identified as uniquely promising are the interactions of electric propulsion and Ni-H batteries, and of onboard data processing/bulk demultiplexing. An attempt is made to furnish a stimulus for system designers to actively seek out synergies rather than wait passively until they emerge.

  15. Synergies with the infrared

    NASA Astrophysics Data System (ADS)

    Alexander, D.

    2016-06-01

    In this solicited talk I will review the synergy between XMM-Newton (and Chandra) and infrared facilities. I will focus on two key advantages from the combination of X-ray and infrared observations. First, infrared observations allow for the identification of the most heavily obscured AGNs that are weak or undetected at X-ray observations, providing a more complete census of AGN activity than from X-ray observations alone. Second, infrared observations provide constraints on the star-formation properties of the AGNs, allowing for insight into the connection between AGN activity and star formation. I will use these key advantages to discuss our progress in identifying a complete census of AGN activity and our understanding of the AGN-star formation connection. I will also review how yet greater gains can be made with future planned and proposed facilities.

  16. Electro-optical Synergy Technique

    PubMed Central

    El-Domyati, Moetaz; El-Ammawi, Tarek S.; Medhat, Walid; Moawad, Osama; Mahoney, My G.

    2010-01-01

    Objectives: Electro-optical synergy technology is one of the most recently described methods for nonablative skin rejuvenation. The aim of this study is to evaluate the effects of electro-optical synergy on connective tissue composition by histological and immunohistochemical techniques coupled with computerized morphometric analysis. Design: A prospective clinical study. Participants: Six volunteers with Fitzpatrick skin types 3 to 4 and Glogau class I to II wrinkles were subjected to three months (6 sessions at 2-week intervals) of electro-optical synergy treatment. Measurements: Standard photographs and skin biopsies were obtained at baseline as well as three and six months after the start of treatment. The authors performed quantitative evaluation of total elastin, tropoelastin, collagen types I, III, and VII, and newly synthesized collagen. Results: Noticeable clinical and histological improvement was observed after electro-optical synergy treatment. A statistically significant increase in the means of collagen types I, III, and VII, as well as newly synthesized collagen, together with increased levels of tropoelastin, were detected, while the mean level of total elastin was significantly decreased at the end of treatment and three months post-treatment. Conclusion: Electro-optical synergy is an effective treatment for contouring facial skin laxity. This modality stimulates the repair processes and reverses the clinical, as well as the histopathological, signs of aging with the advantage of being a relatively risk-free procedure with minimal patient recovery time. PMID:21203352

  17. Differences between kinematic synergies and muscle synergies during two-digit grasping

    PubMed Central

    Tagliabue, Michele; Ciancio, Anna Lisa; Brochier, Thomas; Eskiizmirliler, Selim; Maier, Marc A.

    2015-01-01

    The large number of mechanical degrees of freedom of the hand is not fully exploited during actual movements such as grasping. Usually, angular movements in various joints tend to be coupled, and EMG activities in different hand muscles tend to be correlated. The occurrence of covariation in the former was termed kinematic synergies, in the latter muscle synergies. This study addresses two questions: (i) Whether kinematic and muscle synergies can simultaneously accommodate for kinematic and kinetic constraints. (ii) If so, whether there is an interrelation between kinematic and muscle synergies. We used a reach-grasp-and-pull paradigm and recorded the hand kinematics as well as eight surface EMGs. Subjects had to either perform a precision grip or side grip and had to modify their grip force in order to displace an object against a low or high load. The analysis was subdivided into three epochs: reach, grasp-and-pull, and static hold. Principal component analysis (PCA, temporal or static) was performed separately for all three epochs, in the kinematic and in the EMG domain. PCA revealed that (i) Kinematic- and muscle-synergies can simultaneously accommodate kinematic (grip type) and kinetic task constraints (load condition). (ii) Upcoming grip and load conditions of the grasp are represented in kinematic- and muscle-synergies already during reach. Phase plane plots of the principal muscle-synergy against the principal kinematic synergy revealed (iii) that the muscle-synergy is linked (correlated, and in phase advance) to the kinematic synergy during reach and during grasp-and-pull. Furthermore (iv), pair-wise correlations of EMGs during hold suggest that muscle-synergies are (in part) implemented by coactivation of muscles through common input. Together, these results suggest that kinematic synergies have (at least in part) their origin not just in muscular activation, but in synergistic muscle activation. In short: kinematic synergies may result from muscle

  18. Sensory synergy as environmental input integration

    PubMed Central

    Alnajjar, Fady; Itkonen, Matti; Berenz, Vincent; Tournier, Maxime; Nagai, Chikara; Shimoda, Shingo

    2015-01-01

    The development of a method to feed proper environmental inputs back to the central nervous system (CNS) remains one of the challenges in achieving natural movement when part of the body is replaced with an artificial device. Muscle synergies are widely accepted as a biologically plausible interpretation of the neural dynamics between the CNS and the muscular system. Yet the sensorineural dynamics of environmental feedback to the CNS has not been investigated in detail. In this study, we address this issue by exploring the concept of sensory synergy. In contrast to muscle synergy, we hypothesize that sensory synergy plays an essential role in integrating the overall environmental inputs to provide low-dimensional information to the CNS. We assume that sensor synergy and muscle synergy communicate using these low-dimensional signals. To examine our hypothesis, we conducted posture control experiments involving lateral disturbance with nine healthy participants. Proprioceptive information represented by the changes on muscle lengths were estimated by using the musculoskeletal model analysis software SIMM. Changes on muscles lengths were then used to compute sensory synergies. The experimental results indicate that the environmental inputs were translated into the two dimensional signals and used to move the upper limb to the desired position immediately after the lateral disturbance. Participants who showed high skill in posture control were found to be likely to have a strong correlation between sensory and muscle signaling as well as high coordination between the utilized sensory synergies. These results suggest the importance of integrating environmental inputs into suitable low-dimensional signals before providing them to the CNS. This mechanism should be essential when designing the prosthesis' sensory system to make the controller simpler. PMID:25628523

  19. Are muscle synergies useful for neural control?

    PubMed

    de Rugy, Aymar; Loeb, Gerald E; Carroll, Timothy J

    2013-01-01

    The observation that the activity of multiple muscles can be well approximated by a few linear synergies is viewed by some as a sign that such low-dimensional modules constitute a key component of the neural control system. Here, we argue that the usefulness of muscle synergies as a control principle should be evaluated in terms of errors produced not only in muscle space, but also in task space. We used data from a force-aiming task in two dimensions at the wrist, using an electromyograms (EMG)-driven virtual biomechanics technique that overcomes typical errors in predicting force from recorded EMG, to illustrate through simulation how synergy decomposition inevitably introduces substantial task space errors. Then, we computed the optimal pattern of muscle activation that minimizes summed-squared muscle activities, and demonstrated that synergy decomposition produced similar results on real and simulated data. We further assessed the influence of synergy decomposition on aiming errors (AEs) in a more redundant system, using the optimal muscle pattern computed for the elbow-joint complex (i.e., 13 muscles acting in two dimensions). Because EMG records are typically not available from all contributing muscles, we also explored reconstructions from incomplete sets of muscles. The redundancy of a given set of muscles had opposite effects on the goodness of muscle reconstruction and on task achievement; higher redundancy is associated with better EMG approximation (lower residuals), but with higher AEs. Finally, we showed that the number of synergies required to approximate the optimal muscle pattern for an arbitrary biomechanical system increases with task-space dimensionality, which indicates that the capacity of synergy decomposition to explain behavior depends critically on the scope of the original database. These results have implications regarding the viability of muscle synergy as a putative neural control mechanism, and also as a control algorithm to restore

  20. Examining the Synergy of Practice

    PubMed Central

    2014-01-01

    Public health nurses in Ireland are charged with conducting a home visit to every postnatal mother within 48 hours of hospital discharge. This represents the beginning of a long-term relationship, not only with the mother and newborn child but also with the family. This article fundamentally demonstrates the essential work of the public health nurse in promoting the health of the baby within a family. In this article, the expertise the public health nurse uses in the first visit is examined in the context of 3 competencies: communication, partnerships with the family, and partnerships with individual family members. This expertise provides the foundation for a long-term therapeutic relationship with the family to the essential benefit of the baby’s early childhood growth and developmental milestones. Consequently, the first postnatal visit by public health nursing in Ireland represents a synergy of practice, which provides the foundation for enduring family relationships focused on potentializing both individual family members’ health and the family as a dynamic unit. PMID:27335911

  1. A modular neural model of motor synergies.

    PubMed

    Byadarhaly, Kiran V; Perdoor, Mithun C; Minai, Ali A

    2012-08-01

    Animals such as reptiles, amphibians and mammals (including humans) are mechanically extremely complex. It has been estimated that the human body has between 500 and 1400 degrees of freedom! And yet, these animals can generate an infinite variety of very precise, complicated and goal-directed movements in continuously changing and uncertain environments. Understanding how this is achieved is of great interest to both biologists and engineers. There are essentially two questions that must be addressed: (1) What type of control strategy is used to handle the large number of degrees of freedom involved? and (2) How is this strategy instantiated in the substrate of neural and musculoskeletal elements comprising the animal bodies? The first question has been studied intensively for several decades, providing strong indications that, rather than using standard feedback control based on continuous tracking of desired trajectories, animals' movements emerge from the controlled combination of pre-configured movement primitives or synergies. These synergies represent coordinated activity patterns over groups of muscles, and can be triggered as a whole with controlled amplitude and temporal offset. Complex movements can thus be constructed from the appropriate combination of a relatively small number of synergies, greatly simplifying the control problem. Although experimental studies on animal movements have confirmed the existence of motor synergies, and their utility has been demonstrated in the control of fairly complex robots, their neural basis remains poorly understood. In this paper, we introduce a simple but plausible and general neural model for motor synergies based on the principle that these functional modules reflect the structural modularity of the underlying physical system. Using this model, we show that a small set of synergies selected through a redundancy-reduction principle can generate a rich motor repertoire in a model two-jointed arm system. We

  2. Greenhouses and their humanizing synergies

    NASA Astrophysics Data System (ADS)

    Haeuplik-Meusburger, Sandra; Paterson, Carrie; Schubert, Daniel; Zabel, Paul

    2014-03-01

    Greenhouses in space will require advanced technical systems of automatic watering, soil-less cultivation, artificial lighting, and computerized observation of plants. Functions discussed for plants in space habitats include physical/health requirements and human psychology, social cohesion, as well as the complex sensorial benefits of plants for humans. The authors consider the role of plants in long-term space missions historically since 1971 (Salyut 1) and propose a set of priorities to be considered within the design requirements for greenhouses and constructed environments given a range of benefits associated with plant-human relationships. They cite recent research into the use of greenhouses in extreme environments to reveal the relative importance of greenhouses for people living in isolated locations. Additionally, they put forward hypotheses about where greenhouses might factor into several strata of human health. In a recent design-in-use study of astronauts' experiences in space habitats discussed in Architecture for Astronauts (Springer Press 2011) it was found that besides the basic advantages for life support there are clearly additional "side benefits" for habitability and physical wellbeing, and thus long-term mission success. The authors have composed several key theses regarding the need to promote plant-human relationships in space, including areas where synergy and symbiosis occur. They cite new comprehensive research into the early US Space Program to reveal where programmatic requirements could be added to space architecture to increase the less quantifiable benefits to astronauts of art, recreation, and poetic engagement with their existential condition of estrangement from the planet. Specifically in terms of the technological requirements, the authors propose the integration of a new greenhouse subsystem component into space greenhouses—the Mobile Plant Cultivation Subsystem—a portable, personal greenhouse that can be integrated

  3. Hierarchies of Synergies in Human Movements

    PubMed Central

    Latash, Mark L.; Gorniak, Stacey; Zatsiorsky, Vladimir M.

    2009-01-01

    This brief review addresses the problem of motor redundancy, which exists at many levels of the neuromotor hierarchies involved in the production of voluntary movements. An approach to this problem is described based on the principle of abundance. This approach offers an operational definition for motor synergies using the framework of the uncontrolled manifold hypothesis. It is shown that hierarchical systems have inherent trade-offs between synergies at different control levels. These trade-offs have been demonstrated in experimental studies of human multi-finger pressing and prehension. They are likely to be present in other hierarchical systems, for example those involved in the control of large groups of muscles. The framework of the equilibrium-point hypothesis offers a physiologically based mechanism, which may form the basis for hierarchies of synergies. PMID:20354578

  4. Robustness of muscle synergies during visuomotor adaptation

    PubMed Central

    Gentner, Reinhard; Edmunds, Timothy; Pai, Dinesh K.; d'Avella, Andrea

    2013-01-01

    During visuomotor adaptation a novel mapping between visual targets and motor commands is gradually acquired. How muscle activation patterns are affected by this process is an open question. We tested whether the structure of muscle synergies is preserved during adaptation to a visuomotor rotation. Eight subjects applied targeted isometric forces on a handle instrumented with a force transducer while electromyographic (EMG) activity was recorded from 13 shoulder and elbow muscles. The recorded forces were mapped into horizontal displacements of a virtual sphere with simulated mass, elasticity, and damping. The task consisted of moving the sphere to a target at one of eight equally spaced directions. Subjects performed three baseline blocks of 32 trials, followed by six blocks with a 45° CW rotation applied to the planar force, and finally three wash-out blocks without the perturbation. The sphere position at 100 ms after movement onset revealed significant directional error at the beginning of the rotation, a gradual learning in subsequent blocks, and aftereffects at the beginning of the wash-out. The change in initial force direction was closely related to the change in directional tuning of the initial EMG activity of most muscles. Throughout the experiment muscle synergies extracted using a non-negative matrix factorization algorithm from the muscle patterns recorded during the baseline blocks could reconstruct the muscle patterns of all other blocks with an accuracy significantly higher than chance indicating structural robustness. In addition, the synergies extracted from individual blocks remained similar to the baseline synergies throughout the experiment. Thus synergy structure is robust during visuomotor adaptation suggesting that changes in muscle patterns are obtained by rotating the directional tuning of the synergy recruitment. PMID:24027524

  5. CILT2000: Synergy, Technology, and Teacher Professional Development.

    ERIC Educational Resources Information Center

    Baumgartner, Eric; Hsi, Sherry

    2002-01-01

    Introduces the concept of synergy and synergy research conducted in the context of a water quality project and CILT2000, a meeting of the Center for Innovative Learning Technologies (CILT). Shares ways in which synergy research addresses methodological questions, promotes collaborative partnerships, and contributes to equity. (Contains 16…

  6. Project SYNERGY: Software Support for Underprepared Students. Year Four Report.

    ERIC Educational Resources Information Center

    Miami-Dade Community Coll., FL. Div. of Educational Technologies.

    With funds from the International Business Machines (IBM) Corporation, Project SYNERGY was launched in January 1990 to address the problem of students deficient in basic skills entering colleges. Project SYNERGY I focused on reviewing and compiling a list of useful instructional software for basic skills remediation; Project SYNERGY II focused on…

  7. IT Portfolio Selection and IT Synergy

    ERIC Educational Resources Information Center

    Cho, Woo Je

    2010-01-01

    This dissertation consists of three chapters. The primary objectives of this dissertation are: (1) to provide a methodological framework of IT (Information Technology) portfolio management, and (2) to identify the effect of IT synergy on IT portfolio selection of a firm. The first chapter presents a methodological framework for IT project…

  8. Synergy: People Power for the Classroom

    ERIC Educational Resources Information Center

    Hassard, Jack

    1977-01-01

    Suggests and describes several learning activities that complement a high synergy classroom, i. e., "one which thrives on cooperative use of power." Described are: (1) the stages in using synectics with examples; (2) the techniques of webbing and guiding; (3) development of new games; (4) development of student portfolios; and (5) classroom…

  9. Combining activated carbon adsorption with heterogeneous photocatalytic oxidation: lack of synergy for biologically treated greywater and tetraethylene glycol dimethyl ether.

    PubMed

    Gulyas, Holger; Argáez, Angel Santiago Oria; Kong, Fanzhuo; Jorge, Carlos Liriano; Eggers, Susanne; Otterpohl, Ralf

    2013-01-01

    The aim of the study was to evaluate whether the addition of activated carbon in the photocatalytic oxidation of biologically pretreated greywater and of a polar aliphatic compound gives synergy, as previously demonstrated with phenol. Photocatalytic oxidation kinetics were recorded with fivefold concentrated biologically pretreated greywater and with aqueous tetraethylene glycol dimethyl ether solutions using a UV lamp and the photocatalyst TiO2 P25 in the presence and the absence of powdered activated carbon. The synergy factor, SF, was quantified as the ratio of photocatalytic oxidation rate constant in the presence of powdered activated carbon to the rate constant without activated carbon. No synergy was observed for the greywater concentrate (SF approximately 1). For the aliphatic compound, tetraethylene glycol dimethyl ether, addition of activated carbon actually had an inhibiting effect on photocatalysis (SF < 1), while synergy was confirmed in reference experiments using aqueous phenol solutions. The absence of synergy for the greywater concentrate can be explained by low adsorbability of its organic constituents by activated carbon. Inhibition of the photocatalytic oxidation of tetraethylene glycol dimethyl ether by addition of powdered activated carbon was attributed to shading of the photocatalyst by the activated carbon particles. It was assumed that synergy in the hybrid process was limited to aromatic organics. Regardless of the lack of synergy in the case of biologically pretreated greywater, the addition of powdered activated carbon is advantageous since, due to additional adsorptive removal of organics, photocatalytic oxidation resulted in a 60% lower organic concentration when activated carbon was present after the same UV irradiation time. PMID:24191472

  10. Combining activated carbon adsorption with heterogeneous photocatalytic oxidation: Lack of synergy for biologically treated greywater and tetraethylene glycol dimethyl ether

    PubMed Central

    Gulyas, Holger; Argáez, Ángel Santiago Oria; Kong, Fanzhuo; Jorge, Carlos Liriano; Eggers, Susanne; Otterpohl, Ralf

    2013-01-01

    The aim of the study was to evaluate whether the addition of activated carbon in the photocatalytic oxidation of biologically pretreated greywater and of a polar aliphatic compound gives synergy, as previously demonstrated with phenol. Photocatalytic oxidation kinetics were recorded with fivefold concentrated biologically pretreated greywater and with aqueous tetraethylene glycol dimethyl ether solutions using a UV lamp and the photocatalyst TiO2 P25 in the presence and the absence of powdered activated carbon. The synergy factor, SF, was quantified as the ratio of photocatalytic oxidation rate constant in the presence of powdered activated carbon to the rate constant without activated carbon. No synergy was observed for the greywater concentrate (SF ≈ 1). For the aliphatic compound, tetraethylene glycol dimethyl ether, addition of activated carbon actually had an inhibiting effect on photocatalysis (SF < 1), while synergy was confirmed in reference experiments using aqueous phenol solutions. The absence of synergy for the greywater concentrate can be explained by low adsorbability of its organic constituents by activated carbon. Inhibition of the photocatalytic oxidation of tetraethylene glycol dimethyl ether by addition of powdered activated carbon was attributed to shading of the photocatalyst by the activated carbon particles. It was assumed that synergy in the hybrid process was limited to aromatic organics. Regardless of the lack of synergy in the case of biologically pretreated greywater, the addition of powdered activated carbon is advantageous since, due to additional adsorptive removal of organics, photocatalytic oxidation resulted in a 60% lower organic concentration when activated carbon was present after the same UV irradiation time. PMID:24191472

  11. Polymicrobial synergy and dysbiosis in inflammatory disease

    PubMed Central

    Lamont, Richard J.; Hajishengallis, George

    2014-01-01

    Uncontrolled inflammation of the periodontal area may arise when complex microbial communities transition from a commensal to a pathogenic entity. Communication among constituent species leads to polymicrobial synergy among metabolically compatible organisms that acquire functional specialization within the developing community. Keystone pathogens, even at low abundance, elevate community virulence and the resulting dysbiotic community targets specific aspects of host immunity to further disable immune surveillance while promoting an overall inflammatory response. Inflammophilic organisms benefit from proteinaceous substrates derived from inflammatory tissue breakdown. Inflammation and dysbiosis reinforce each other and the escalating environmental changes further select for a pathobiotic community. We have synthesized the polymicrobial synergy and dysbiotic components of the process into a new model for inflammatory diseases. PMID:25498392

  12. Synergy in protein-osmolyte mixtures.

    PubMed

    Rösgen, Jörg

    2015-01-01

    Virtually all taxa use osmolytes to protect cells against biochemical stress. Osmolytes often occur in mixtures, such as the classical combination of urea with TMAO (trimethylamine N-oxide) in cartilaginous fish or the cocktail of at least six different osmolytes in the kidney. The concentration patterns of osmolyte mixtures found in vivo make it likely that synergy between them plays an important role. Using statistical mechanical n-component Kirkwood-Buff theory, we show from first principles that synergy in protein-osmolyte systems can arise from two separable sources: (1) mutual alteration of protein surface solvation and (2) effects mediated through bulk osmolyte chemical activities. We illustrate both effects in a four-component system with the experimental example of the unfolding of a notch ankyrin domain in urea-TMAO mixtures, which make urea a less effective denaturant and TMAO a more effective stabilizer. Protein surface effects are primarily responsible for this synergy. The specific patterns of surface solvation point to denatured state expansion as the main factor, as opposed to direct competition. PMID:25490052

  13. Toward synergy-based brain-machine interfaces.

    PubMed

    Vinjamuri, Ramana; Weber, Douglas J; Mao, Zhi-Hong; Collinger, Jennifer L; Degenhart, Alan D; Kelly, John W; Boninger, Michael L; Tyler-Kabara, Elizabeth C; Wang, Wei

    2011-09-01

    This paper demonstrates a synergy-based brain-machine interface that uses low-dimensional command signals to control a high dimensional virtual hand. First, temporal postural synergies were extracted from the angular velocities of finger joints of five healthy subjects when they performed hand movements that were similar to activities of daily living. Two synergies inspired from the extracted synergies, namely, two-finger pinch and whole-hand grasp, were used in real-time brain control, where a virtual hand with 10 degrees of freedom was controlled to grasp or pinch virtual objects. These two synergies were controlled by electrocorticographic (ECoG) signals recorded from two electrodes of an electrode array that spanned motor and speech areas of an individual with intractable epilepsy, thus demonstrating closed loop control of a synergy-based brain-machine interface. PMID:21708506

  14. Leveraging synergy for multiple agent infotaxis

    SciTech Connect

    Gintautas, Vadas; Hagberg, Aric A; Bettencourt, Luis M A

    2008-01-01

    Social computation, whether in the form of a search performed by a swarm of agents or the predictions of markets, often supplies remarkably good solutions to complex problems, which often elude the best experts. There is an intuition, built upon many anecdotal examples, that pervading principles are at play that allow individuals trying to solve a problem locally to aggregate their information to arrive at an outcome superior than any available to isolated parties. Here we show that the general structure of this problem can be cast in terms of information theory and derive general mathematical conditions for information sharing and coordination that lead to optimal multi-agent searches. Specifically we illustrate the problem in terms of the construction of local search algorithms for autonomous agents looking for the spatial location of a stochastic source. We explore the types of search problems -defined in terms of the properties of the source and the nature of measurements at each sensor -for which coordination among multiple searchers yields an advantage beyond that gained by having the same number of independent searchers. We assert that effective coordination corresponds to synergy and that ineffective coordination corresponds to redundancy as defined using information theory. We classify explicit types of sources in terms of their potential for synergy. We show that sources that emit uncorrelated particles based on a Poisson process, provide no opportunity for synergetic coordination while others, particularly sources that emit correlated signals, do allow for strong synergy between searchers. These general considerations are crucial for designing optimal algorithms for particular search problems in real world settings.

  15. Modulation of Chemokine Responses: Synergy and Cooperativity

    PubMed Central

    Proudfoot, Amanda E. I.; Uguccioni, Mariagrazia

    2016-01-01

    Chemokine biology is mediated by more complex interactions than simple monomolecular ligand–receptor interactions, as chemokines can form higher order quaternary structures, which can also be formed after binding to glycosaminoglycans (GAGs) on endothelial cells, and their receptors are found as dimers and/or oligomers at the cell surface. Due to the complexity of the chemokine binding and signaling system, several mechanisms have been proposed to provide an explanation for the synergy observed between chemokines in leukocyte migration. Pioneering studies on interactions between different chemokines have revealed that they can act as antagonists, or synergize with other chemokines. The synergism can occur at different levels, involving either two chemokine receptors triggered simultaneously or sequentially exposed to their agonists, or the activation of one type of chemokine receptor triggered by chemokine heterocomplexes. In addition to the several chemokines that, by forming a heterocomplex with chemokine receptor agonists, act as enhancers of molecules of the same family, we have recently identified HMGB1, an endogenous damage-associated molecular patterns (DAMPs) molecule, as an enhancer of the activity of CXCL12. It is now evident that synergism between chemokines is crucial at the very early stage of inflammation. In addition, the low-affinity interaction with GAGs has recently been shown to induce cooperativity allowing synergy or inhibition of activity by displacement of other ligands. PMID:27242790

  16. Neurosurgery, "neurospine," and neuroscience: a vital synergy?

    PubMed

    Nowitzke, Adrian

    2008-10-01

    A fundamental dilemma that faces both neurosurgery in general and the subspecialty field of spine surgery is the question of whether those who trained in the former and now work in the latter should maintain their links with their origins and remain under the broader umbrella of neurosurgery, or whether they should develop their own organizational structure and identity separate from organized neurosurgery. This challenge raises many questions with respect to future potential for growth and development, professional identity, and collegiality. This paper is an edited version of an invited speech to the 2007 Annual Meeting of the Joint Section on Disorders of the Spine and Peripheral Nerves. It uses the concept of synergy to review relevant history and explore possible future options for neurosurgery, neurospine, and neuroscience. An example from medical politics is used to illustrate the importance of perspective in approaching these questions, and examples of current therapeutic cutting-edge endeavors highlight the need for team-based behavior that takes a broad view. The premise of the paper is that while individual and specialty aspirations need to be acknowledged, considered, and managed, the results from truly working together will be greater than the sum of the individual efforts-synergy. PMID:18939916

  17. Tapping Geography's Potential for Synergy with Creative Instructional Approaches

    ERIC Educational Resources Information Center

    Conway-Gomez, Kristen; Williams, Nikki; Atkinson-Palombo, Carol; Ahlqvist, Ola; Kim, Eje; Morgan, Miranda

    2011-01-01

    We define synergy, explain its importance within the context of rapidly changing academia, and provide examples of how geographic educators have used creative instructional approaches to create synergies. Both the content of geography and some of the instructional approaches used by geographic educators support the discipline's ability to deliver…

  18. Muscle synergies evoked by microstimulation are preferentially encoded during behavior

    PubMed Central

    Overduin, Simon A.; d'Avella, Andrea; Carmena, Jose M.; Bizzi, Emilio

    2014-01-01

    Electrical microstimulation studies provide some of the most direct evidence for the neural representation of muscle synergies. These synergies, i.e., coordinated activations of groups of muscles, have been proposed as building blocks for the construction of motor behaviors by the nervous system. Intraspinal or intracortical microstimulation (ICMS) has been shown to evoke muscle patterns that can be resolved into a small set of synergies similar to those seen in natural behavior. However, questions remain about the validity of microstimulation as a probe of neural function, particularly given the relatively long trains of supratheshold stimuli used in these studies. Here, we examined whether muscle synergies evoked during ICMS in two rhesus macaques were similarly encoded by nearby motor cortical units during a purely voluntary behavior involving object reach, grasp, and carry movements. At each microstimulation site we identified the synergy most strongly evoked among those extracted from muscle patterns evoked over all microstimulation sites. For each cortical unit recorded at the same microstimulation site, we then identified the synergy most strongly encoded among those extracted from muscle patterns recorded during the voluntary behavior. We found that the synergy most strongly evoked at an ICMS site matched the synergy most strongly encoded by proximal units more often than expected by chance. These results suggest a common neural substrate for microstimulation-evoked motor responses and for the generation of muscle patterns during natural behaviors. PMID:24634652

  19. Muscle synergy analysis in children with cerebral palsy

    NASA Astrophysics Data System (ADS)

    Tang, Lu; Li, Fei; Cao, Shuai; Zhang, Xu; Wu, De; Chen, Xiang

    2015-08-01

    Objective. To explore the mechanism of lower extremity dysfunction of cerebral palsy (CP) children through muscle synergy analysis. Approach. Twelve CP children were involved in this study, ten adults (AD) and eight typically developed (TD) children were recruited as a control group. Surface electromyographic (sEMG) signals were collected bilaterally from eight lower limb muscles of the subjects during forward walking at a comfortable speed. A nonnegative matrix factorization algorithm was used to extract muscle synergies. In view of muscle synergy differences in number, structure and symmetry, a model named synergy comprehensive assessment (SCA) was proposed to quantify the abnormality of muscle synergies. Main results. There existed larger variations between the muscle synergies of the CP group and the AD group in contrast with the TD group. Fewer mature synergies were recruited in the CP group, and many abnormal synergies specific to the CP group appeared. Specifically, CP children were found to recruit muscle synergies with a larger difference in structure and symmetry between two legs of one subject and different subjects. The proposed SCA scale demonstrated its great potential to quantitatively assess the lower-limb motor dysfunction of CP children. SCA scores of the CP group (57.00 ± 16.78) were found to be significantly less (p < 0.01) than that of the control group (AD group: 95.74 ± 2.04; TD group: 84.19 ± 11.76). Significance. The innovative quantitative results of this study can help us to better understand muscle synergy abnormality in CP children, which is related to their motor dysfunction and even the physiological change in their nervous system.

  20. A computational analysis of motor synergies by dynamic response decomposition

    PubMed Central

    Alessandro, Cristiano; Carbajal, Juan Pablo; d'Avella, Andrea

    2014-01-01

    Analyses of experimental data acquired from humans and other vertebrates have suggested that motor commands may emerge from the combination of a limited set of modules. While many studies have focused on physiological aspects of this modularity, in this paper we propose an investigation of its theoretical foundations. We consider the problem of controlling a planar kinematic chain, and we restrict the admissible actuations to linear combinations of a small set of torque profiles (i.e., motor synergies). This scheme is equivalent to the time-varying synergy model, and it is formalized by means of the dynamic response decomposition (DRD). DRD is a general method to generate open-loop controllers for a dynamical system to solve desired tasks, and it can also be used to synthesize effective motor synergies. We show that a control architecture based on synergies can greatly reduce the dimensionality of the control problem, while keeping a good performance level. Our results suggest that in order to realize an effective and low-dimensional controller, synergies should embed features of both the desired tasks and the system dynamics. These characteristics can be achieved by defining synergies as solutions to a representative set of task instances. The required number of synergies increases with the complexity of the desired tasks. However, a possible strategy to keep the number of synergies low is to construct solutions to complex tasks by concatenating synergy-based actuations associated to simple point-to-point movements, with a limited loss of performance. Ultimately, this work supports the feasibility of controlling a non-linear dynamical systems by linear combinations of basic actuations, and illustrates the fundamental relationship between synergies, desired tasks and system dynamics. PMID:24474915

  1. Representation of Muscle Synergies in the Primate Brain

    PubMed Central

    d'Avella, Andrea; Roh, Jinsook; Carmena, Jose M.; Bizzi, Emilio

    2015-01-01

    Evidence suggests that the CNS uses motor primitives to simplify movement control, but whether it actually stores primitives instead of computing solutions on the fly to satisfy task demands is a controversial and still-unanswered possibility. Also in contention is whether these primitives take the form of time-invariant muscle coactivations (“spatial” synergies) or time-varying muscle commands (“spatiotemporal” synergies). Here, we examined forelimb muscle patterns and motor cortical spiking data in rhesus macaques (Macaca mulatta) handling objects of variable shape and size. From these data, we extracted both spatiotemporal and spatial synergies using non-negative decomposition. Each spatiotemporal synergy represents a sequence of muscular or neural activations that appeared to recur frequently during the animals' behavior. Key features of the spatiotemporal synergies (including their dimensionality, timing, and amplitude modulation) were independently observed in the muscular and neural data. In addition, both at the muscular and neural levels, these spatiotemporal synergies could be readily reconstructed as sequential activations of spatial synergies (a subset of those extracted independently from the task data), suggestive of a hierarchical relationship between the two levels of synergies. The possibility that motor cortex may execute even complex skill using spatiotemporal synergies has novel implications for the design of neuroprosthetic devices, which could gain computational efficiency by adopting the discrete and low-dimensional control that these primitives imply. SIGNIFICANCE STATEMENT We studied the motor cortical and forearm muscular activity of rhesus macaques (Macaca mulatta) as they reached, grasped, and carried objects of varied shape and size. We applied non-negative matrix factorization separately to the cortical and muscular data to reduce their dimensionality to a smaller set of time-varying “spatiotemporal” synergies. Each synergy

  2. Synergies among extinction drivers under global change.

    PubMed

    Brook, Barry W; Sodhi, Navjot S; Bradshaw, Corey J A

    2008-08-01

    If habitat destruction or overexploitation of populations is severe, species loss can occur directly and abruptly. Yet the final descent to extinction is often driven by synergistic processes (amplifying feedbacks) that can be disconnected from the original cause of decline. We review recent observational, experimental and meta-analytic work which together show that owing to interacting and self-reinforcing processes, estimates of extinction risk for most species are more severe than previously recognised. As such, conservation actions which only target single-threat drivers risk being inadequate because of the cascading effects caused by unmanaged synergies. Future work should focus on how climate change will interact with and accelerate ongoing threats to biodiversity, such as habitat degradation, overexploitation and invasive species. PMID:18582986

  3. Space Propulsion Synergy Group ETO technology assessments

    NASA Astrophysics Data System (ADS)

    Bray, James

    The Space Propulsion Synergy Group (SPSG), which was chartered to support long-range strategic planning, has, using a broad industry/government team, evaluated and achieved consensus on the vehicles, propulsion systems, and propulsion technologies that have the best long-term potential for achieving desired system attributes. The breakthrough that enabled broad consensus was developing criteria that are measurable a priori. The SPSG invented a dual prioritization approach that balances long-term strategic thrusts with current programmatic constraints. This enables individual program managers to make decisions based on both individual project needs and long-term strategic needs. Results indicate that an SSTO using an integrated modular engine has the best long-term potential for a 20 Klb class vehicle, and that health monitoring and control technologies are among the highest dual priority liquid rocket technologies.

  4. Generational Differences in Work-Family Conflict and Synergy

    PubMed Central

    Beutell, Nicholas J.

    2013-01-01

    This paper examines differences in work-family conflict and synergy among the four generational groups represented in the contemporary workforce: Generation Y Generation X, Baby Boomers, and Matures using data from the 2008 National Study of the Changing Workforce (n = 3,502). Significant generational differences were found for work-family conflict (work interfering with family and family interfering with work) but not for work-family synergy. Mental health and job pressure were the best predictors of work interfering with family conflict for each generational group. Work-family synergy presented a more complex picture. Work-family conflict and synergy were significantly related to job, marital, and life satisfaction. Implications and directions for future research are discussed. PMID:23783221

  5. Generational differences in work-family conflict and synergy.

    PubMed

    Beutell, Nicholas J

    2013-06-01

    This paper examines differences in work-family conflict and synergy among the four generational groups represented in the contemporary workforce: Generation Y Generation X, Baby Boomers, and Matures using data from the 2008 National Study of the Changing Workforce (n = 3,502). Significant generational differences were found for work-family conflict (work interfering with family and family interfering with work) but not for work-family synergy. Mental health and job pressure were the best predictors of work interfering with family conflict for each generational group. Work-family synergy presented a more complex picture. Work-family conflict and synergy were significantly related to job, marital, and life satisfaction. Implications and directions for future research are discussed. PMID:23783221

  6. Brain Connectivity Associated with Muscle Synergies in Humans

    PubMed Central

    Rana, Manku; Yani, Moheb S.; Asavasopon, Skulpan; Fisher, Beth E.

    2015-01-01

    The human brain is believed to simplify the control of the large number of muscles in the body by flexibly combining muscle coordination patterns, termed muscle synergies. However, the neural connectivity allowing the human brain to access and coordinate muscle synergies to accomplish functional tasks remains unknown. Here, we use a surprising pair of synergists in humans, the flexor hallucis longus (FHL, a toe flexor) and the anal sphincter, as a model that we show to be well suited in elucidating the neural connectivity underlying muscle synergy control. First, using electromyographic recordings, we demonstrate that voluntary FHL contraction is associated with synergistic anal sphincter contraction, but voluntary anal sphincter contraction occurs without FHL contraction. Second, using fMRI, we show that two important medial wall motor cortical regions emerge in relation to these tasks: one located more posteriorly that preferentially activates during voluntary FHL contraction and one located more anteriorly that activates during both voluntary FHL contraction as well as voluntary anal sphincter contraction. Third, using transcranial magnetic stimulation, we demonstrate that the anterior region is more likely to generate anal sphincter contraction than FHL contraction. Finally, using a repository resting-state fMRI dataset, we demonstrate that the anterior and posterior motor cortical regions have significantly different functional connectivity with distinct and distant brain regions. We conclude that specific motor cortical regions in humans provide access to different muscle synergies, which may allow distinct brain networks to coordinate muscle synergies during functional tasks. SIGNIFICANCE STATEMENT How the human nervous system coordinates activity in a large number of muscles is a fundamental question. The brain and spinal cord are believed to simplify the control of muscles by grouping them into functional units called muscle synergies. Motor cortex is

  7. Do muscle synergies reduce the dimensionality of behavior?

    PubMed Central

    Kuppuswamy, Naveen; Harris, Christopher M.

    2014-01-01

    The muscle synergy hypothesis is an archetype of the notion of Dimensionality Reduction (DR) occurring in the central nervous system due to modular organization. Toward validating this hypothesis, it is important to understand if muscle synergies can reduce the state-space dimensionality while maintaining task control. In this paper we present a scheme for investigating this reduction utilizing the temporal muscle synergy formulation. Our approach is based on the observation that constraining the control input to a weighted combination of temporal muscle synergies also constrains the dynamic behavior of a system in a trajectory-specific manner. We compute this constrained reformulation of system dynamics and then use the method of system balancing for quantifying the DR; we term this approach as Trajectory Specific Dimensionality Analysis (TSDA). We then investigate the consequence of minimization of the dimensionality for a given task. These methods are tested in simulations on a linear (tethered mass) and a non-linear (compliant kinematic chain) system. Dimensionality of various reaching trajectories is compared when using idealized temporal synergies. We show that as a consequence of this Minimum Dimensional Control (MDC) model, smooth straight-line Cartesian trajectories with bell-shaped velocity profiles emerged as the optima for the reaching task. We also investigated the effect on dimensionality due to adding via-points to a trajectory. The results indicate that a trajectory and synergy basis specific DR of behavior results from muscle synergy control. The implications of these results for the synergy hypothesis, optimal motor control, motor development, and robotics are discussed. PMID:25002844

  8. Synergy optimization and operation management on syndicate complementary knowledge cooperation

    NASA Astrophysics Data System (ADS)

    Tu, Kai-Jan

    2014-10-01

    The number of multi enterprises knowledge cooperation has grown steadily, as a result of global innovation competitions. I have conducted research based on optimization and operation studies in this article, and gained the conclusion that synergy management is effective means to break through various management barriers and solve cooperation's chaotic systems. Enterprises must communicate system vision and access complementary knowledge. These are crucial considerations for enterprises to exert their optimization and operation knowledge cooperation synergy to meet global marketing challenges.

  9. Synergies of space exploration and Earth science

    NASA Astrophysics Data System (ADS)

    Chung, Y.; Ehrenfreund, P.; Rummel, J.; Peter, N.

    2009-04-01

    A more flexible policy basis from which to manage our planet in the 21st century is desirable. As one contribution, we note that synergies between space exploration and the preservation of our habitat do exist, and that protecting life on Earth requires similar concepts and information as investigations of life beyond the Earth, including the expansion of human presence in space. Instrumentation and data handling to observe both planetary objects and planet Earth are based on similar techniques. Moreover, while planetary surface operations are conducted under different conditions, the technology to probe the surface and subsurface of both the Earth and other planets requires similar tools, such as radar, seismometers, and drilling devices. The Earth observation community has developed some exemplary tools and has featured a successful international cooperation in data handling and sharing that could be equally well applied to robotic planetary exploration. Likewise, the education and awareness of society can benefit tremendously from knowledge of the overall habitability of our Solar System, including steps taken to prevent biological cross-contamination (planetary protection). Here we propose a network involving both communities that will enable the interchange of scientific insights and the development of new policies and management strategies. Those tools can provide a vital forum through which the management of this planet can be assisted, and in which a new bridge between the Earth-centric and space-centric communities can be built.

  10. Synergies with CTA and VHE Astrophysics

    NASA Astrophysics Data System (ADS)

    Hofmann, W.

    2016-06-01

    The Cherenkov Telescope Array (CTA) is a next-generation observatory for very high energy (VHE) gamma-ray astronomy. With one array of imaging atmospheric Cherenkov telescopes each in the northern and southern hemispheres, CTA will provide full-sky coverage, enhance flux sensitivity by one order of magnitude compared to current instruments, cover gamma-ray energies from 20 GeV to 300 TeV, and provide angular resolution of a few arc-minutes across a multi-degree field of view. In the context of its Key Science Projects (KSPs), CTA will conduct a census of particle acceleration in the universe, with quarter-sky extragalactic, full-plane Galactic and Large Magellanic Cloud surveys planned. Additional KSPs are focused on transients, acceleration up to PeV energies in our own galaxy, active galaxies, star-forming systems on a wide range of scales, and the Perseus cluster of galaxies. A major element of the programme is the search for dark matter, in particular the annihilation signature of WIMPs. Like for current-generation VHE instruments, CTA science will strongly rely upon multiwavelength observations of sources, with the X-ray domain playing a particularly crucial role. The presentation will briefly introduce CTA, summarize its science perspectives, and address the synergies with instruments in other wavebands.

  11. Global mental health and neuroscience: potential synergies.

    PubMed

    Stein, Dan J; He, Yanling; Phillips, Anthony; Sahakian, Barbara J; Williams, John; Patel, Vikram

    2015-02-01

    Global mental health has emerged as an important specialty. It has drawn attention to the burden of mental illness and to the relative gap in mental health research and services around the world. Global mental health has raised the question of whether this gap is a developmental issue, a health issue, a human rights issue, or a combination of these issues-and it has raised awareness of the need to develop new approaches for building capacity, mobilising resources, and closing the research and treatment gap. Translational neuroscience has also advanced. It comprises an important conceptual approach to understanding the neurocircuitry and molecular basis of mental disorders, to rethinking how best to undertake research on the aetiology, assessment, and treatment of these disorders, with the ultimate aim to develop entirely new approaches to prevention and intervention. Some apparent contrasts exist between these fields; global mental health emphasises knowledge translation, moving away from the bedside to a focus on health systems, whereas translational neuroscience emphasises molecular neuroscience, focusing on transitions between the bench and bedside. Meanwhile, important opportunities exist for synergy between the two paradigms, to ensure that present opportunities in mental health research and services are maximised. Here, we review the approaches of global mental health and clinical neuroscience to diagnosis, pathogenesis, and intervention, and make recommendations for facilitating an integration of these two perspectives. PMID:26359754

  12. Space Propulsion Synergy Group ETO technology assessments

    NASA Astrophysics Data System (ADS)

    Bray, James

    There exists within the aerospace community a widely recognized need to improve future space launch systems. While these needs have been expressed by many national committees, potential solutions have not achieved consensus nor have they endured. Facing the challenge to remain competitive with limited national resources, the U.S. must improve its strategic planning efforts. A nationally accepted strategic plan for space would enable a focused research & development program. The Space Propulsion Synergy Group (SPSG), chartered to support long range strategic planning, has achieved several breakthroughs. First, using a broad industry/government team, the SPSG evaluated and achieved consensus on the vehicles, propulsion systems, and propulsion technologies that have the best long term potential for achieving desired system attributes. The breakthrough that enabled broad consensus was developing criteria that are measurable a-priori. Second, realizing that systems having the best long term payoffs can loose support when constraints are tight, the SPSG invented a dual prioritization approach that balances long term strategic thrusts with current programmatic constraints. This breakthrough enables individual program managers to make decisions based on both individual project needs and long term strategic needs. Results indicate that a SSTO using an integrated modular engine has the best long term potential for a 20 Klb class vehicle and that health monitoring and control technologies rank among the highest dual priority liquid rocket technologies.

  13. Synergistic hybrid organic-inorganic aerogels.

    PubMed

    Wang, Xiao; Jana, Sadhan C

    2013-07-10

    A class of inorganic-organic hybrid mesoporous aerogel structure was synthesized by growing gel in a gel. In Type 1, silica gels were grown inside the macropores of thermoreversible syndiotactic polystyrene (sPS) gel, while Type 2 hybrid aerogels were obtained by thermoreversible gelation of sPS chains in the mesopores of preformed silica gel. The hybrid gels were converted into aerogels by exchanging the solvent with liquid carbon dioxide followed by supercritical drying. The hybrid aerogels presented cocontinuous networks of pearl-necklace silica particles and crystalline strands of sPS and exhibited the "petal effect" due to the presence of superhydrophobic sPS and hygroscopic silica. The compressive modulus and compressive strain show large enhancements over sPS and silica aerogels indicating synergy, although Type 1 hybrid aerogels were found to be more robust. The hybrid aerogels showed fast absorption and high absorption capacity for a representative hydrocarbon liquid. PMID:23773123

  14. Synergy for a Strong Future FY 2008

    SciTech Connect

    Devore, L; Chrzanowski, P

    2008-11-06

    Lawrence Livermore National Security, LLC is committed to delivering the best combination of scientific research, technology development, business management, and safe, secure operations in support of Lawrence Livermore National Laboratory's critical national security mission. LLNS was formed specifically to manage LLNL for the Department of Energy's National Nuclear Security Administration. LLNS consists of a team of five organizations renowned for their expertise and accomplishments throughout the U.S. nuclear weapons complex and beyond - Bechtel National, University of California, Babcock & Wilcox, Washington Division of URS Corporation, and Battelle. Bechtel is the nation's largest engineering and construction firm and a leader in project management. The University of California is the world's largest public research institution. Babcock & Wilcox and the Washington Division of URS Corporation are top nuclear facilities contractors and between them manage four of DOE's five safest sites. Battelle is a global leader in science and technology development and commercialization. The LLNS Board of Governors provides oversight for the management of the Laboratory and holds the Director and LLNS President responsible for the Laboratory's performance. The Board has seven standing committees that assist in assessing Laboratory performance and monitoring risks and internal controls. Through the Board of Governors, the Laboratory can reach back to LLNS partner organizations to help ensure that it fulfills its national security mission with excellence in scientific research, technology development, business management, and safe, secure operations. LLNS assumed management of LLNL on October 1, 2007. This report highlights LLNS accomplishments in FY2008, its first year as the Laboratory's managing contractor. It is clear that LLNS and the Laboratory have exploited numerous synergies inherent in their relationship - for example, science and engineering, mission and operations

  15. Radiologic and Near-Infrared/Optical Spectroscopic Imaging: Where Is the Synergy?

    PubMed Central

    Pogue, Brian W.; Leblond, Frederic; Krishnaswamy, Venkataramanan; Paulsen, Keith D.

    2010-01-01

    OBJECTIVE Optical and radiologic imaging are commonly used in preclinical research, and research into combined instruments for human applications is showing promise. The purpose of this article is to outline the fundamental limitations and advantages and to review the available systems. The emerging developments and future potential will be summarized. CONCLUSION Integration of hybrid systems is now routine at the preclinical level and appears in the form of specialized packages in which performance varies considerably. The synergy is commonly focused on using spatial localization from radiographs to provide structural data for spectroscopy; however, applications also exist in which the spectroscopy informs the use of radiologic imaging. Examples of clinical systems under research and development are shown. PMID:20651186

  16. Resource synergy in stream periphyton communities

    SciTech Connect

    Hill, Walter; Fanta, S.E.; Roberts, Brian J; Francoeur, Steven N.

    2011-03-01

    1. Light and nutrients play pivotal roles in determining the growth of autotrophs, yet the potential for synergistic interactions between the two resources in algal communities is poorly understood, especially in stream ecosystems. In this study, light and phosphorus were manipulated in large experimental streams to examine resource colimitation and synergy in stream periphyton. 2. Whole-stream metabolism was simultaneously limited by light and phosphorus. Increasing the supply of either light or phosphorus resulted in significant increases in primary production and the transformation of the streams from heterotrophy to autotrophy. 3. Resource-driven changes in periphyton community structure occurred in concert with changes in production. Algal assemblages in highly shaded streams were composed primarily of small diatoms such as Achnanthidium minutissima, whereas larger diatoms such as Melosira varians predominated at higher irradiances. Phosphorus enrichment had relatively little effect on assemblage structure, but it did substantially diminish the abundance of Meridion circulare, a diatom whose mucilaginous colonies were conspicuously abundant in phosphorus-poor, high-light streams. Bacterial biomass declined relative to algal biomass with increases in primary productivity, regardless of whether the increases were caused by light or phosphorus. 4. Synergistic effects on primary production appeared to occur because the availability of one resource facilitated the utilization of the other. Light increased the abundance of large diatoms, which are known to convert high concentrations of nutrients into primary production more effectively than smaller taxa. Phosphorus enrichment led to the replacement of Meridion circulare by non-mucilaginous taxa in phosphorus-enriched streams, and we hypothesize that this change enabled more efficient use of light in photosynthesis. Higher ratios of chlorophyll a : biomass in phosphorus-enriched streams may have also led to more

  17. Space and Terrestrial Photovoltaics: Synergy and Diversity

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila; Raffaelle, Ryne; Emery, Keith

    2002-01-01

    A historical view of the research and development in photovoltaics from the perspective of both the terrestrial and the space communities is presented from the early days through the '70s and '80s and the '90s and beyond. The synergy of both communities in the beginning and once again in the present and hopefully future are highlighted, with examples of the important features in each program. The space community which was impressed by the light-weight and reliability of photovoltaics drove much of the early development. Even up to today, nearly every satellites and other scientific space probe that has been launched has included some solar power. However, since the cost of these power systems were only a small fraction of the satellite and launch cost, the use of much of this technology for the terrestrial marketplace was not feasible. It was clear that the focus of the terrestrial community would be best served by reducing costs. This would include addressing a variety of manufacturing issues and raising the rate of production. Success in these programs and a resulting globalization of effort resulted in major strides in the reduction of PV module costs and increased production. Although, the space community derived benefit from some of these advancements, its focus was on pushing the envelope with regard to cell efficiency. The gap between theoretical efficiencies and experimental efficiencies for silicon, gallium arsenide and indium phosphide became almost non-existent. Recent work by both communities have focused on the development thin film cells of amorphous silicon, CuInSe2 and CdTe. These cells hold the promise of lower costs for the terrestrial community as well as possible flexible substrates, better radiation resistance, and higher specific power for the space community. It is predicted that future trends in both communities will be directed toward advances through the application of nanotechnology. A picture is emerging in which the space and

  18. Nuclear and Renewable Energy Synergies Workshop: Report of Proceedings

    SciTech Connect

    Ruth, M.; Antkowiak, M.; Gossett, S.

    2011-12-01

    Two of the major challenges the U.S. energy sector faces are greenhouse gas emissions and oil that is both imported and potentially reaching a peak (the point at which maximum extraction is reached). Interest in development of both renewable and nuclear energy has been strong because both have potential for overcoming these challenges. Research in both energy sources is ongoing, but relatively little research has focused on the potential benefits of combining nuclear and renewable energy. In September 2011, the Joint Institute for Strategic Energy Analysis (JISEA) convened the Nuclear and Renewable Energy Synergies Workshop at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) to identify potential synergies and strategic leveraging opportunities between nuclear energy and renewable energy. Industry, government, and academic thought leaders gathered to identify potential broad categories of synergies and brainstorm topic areas for additional analysis and research and development (R&D). This report records the proceedings and outcomes of the workshop.

  19. Understanding Human Motion Skill with Peak Timing Synergy

    NASA Astrophysics Data System (ADS)

    Ueno, Ken; Furukawa, Koichi

    The careful observation of motion phenomena is important in understanding the skillful human motion. However, this is a difficult task due to the complexities in timing when dealing with the skilful control of anatomical structures. To investigate the dexterity of human motion, we decided to concentrate on timing with respect to motion, and we have proposed a method to extract the peak timing synergy from multivariate motion data. The peak timing synergy is defined as a frequent ordered graph with time stamps, which has nodes consisting of turning points in motion waveforms. A proposed algorithm, PRESTO automatically extracts the peak timing synergy. PRESTO comprises the following 3 processes: (1) detecting peak sequences with polygonal approximation; (2) generating peak-event sequences; and (3) finding frequent peak-event sequences using a sequential pattern mining method, generalized sequential patterns (GSP). Here, we measured right arm motion during the task of cello bowing and prepared a data set of the right shoulder and arm motion. We successfully extracted the peak timing synergy on cello bowing data set using the PRESTO algorithm, which consisted of common skills among cellists and personal skill differences. To evaluate the sequential pattern mining algorithm GSP in PRESTO, we compared the peak timing synergy by using GSP algorithm and the one by using filtering by reciprocal voting (FRV) algorithm as a non time-series method. We found that the support is 95 - 100% in GSP, while 83 - 96% in FRV and that the results by GSP are better than the one by FRV in the reproducibility of human motion. Therefore we show that sequential pattern mining approach is more effective to extract the peak timing synergy than non-time series analysis approach.

  20. Identification of muscle synergies associated with gait transition in humans

    PubMed Central

    Hagio, Shota; Fukuda, Mizuho; Kouzaki, Motoki

    2015-01-01

    There is no theoretical or empirical evidence to suggest how the central nervous system (CNS) controls a variety of muscles associated with gait transition between walking and running. Here, we examined the motor control during a gait transition based on muscle synergies, which modularly organize functionally similar muscles. To this end, the subjects walked or ran on a treadmill and performed a gait transition spontaneously as the treadmill speed increased or decreased (a changing speed condition) or voluntarily following an experimenter’s instruction at constant treadmill speed (a constant speed condition). Surface electromyograms (EMGs) were recorded from 11 lower limb muscles bilaterally. We then extracted the muscle weightings of synergies and their activation coefficients from the EMG data using non-negative matrix factorization. As a result, the gait transition was controlled by approximately 9 muscle synergies, which were common during a walking and running, and their activation profiles were changed before and after a gait transition. Near a gait transition, the peak activation phases of the synergies, which were composed of plantar flexor muscles, were shifted to an earlier phase at the walk-to-run transition, and vice versa. The shifts were gradual in the changing speed condition, but an abrupt change was observed in the constant speed condition. These results suggest that the CNS low-dimensionally regulate the activation profiles of the specific synergies based on afferent information (spontaneous gait transition) or by changing only the descending neural input to the muscle synergies (voluntary gait transition) to achieve a gait transition. PMID:25713525

  1. Bioinspired Hybrid White Light-Emitting Diodes.

    PubMed

    Weber, Michael D; Niklaus, Lukas; Pröschel, Marlene; Coto, Pedro B; Sonnewald, Uwe; Costa, Rubén D

    2015-10-01

    The first bioinspired hybrid white-light-emitting diodes (bio-HLEDs) featuring protein cascade coatings are presented. For easy fabrication a new strategy to stabilize proteins in rubber-like material was developed. The synergy between the excellent features of fluorescent proteins and the easily processed rubber produces bio-HLEDs with less than 10% loss in luminous efficiency over 100 hours. PMID:26271025

  2. Effects of fatigue on synergies in a hierarchical system

    PubMed Central

    Singh, Tarkeshwar; Zatsiorsky, Vladimir M.; Latash, Mark L.

    2013-01-01

    We investigated the effect of fatigue produced by timed maximal voluntary contraction (MVC) of the index finger of one of the hands on performance in MVC and accurate cyclic force production tasks in right-handed subjects. Based on earlier studies, we hypothesized that fatigue would produce an increase in the indices of force-stabilizing synergies in both hands as well as between the hands in two-hand tasks. Synergies were defined as co-varied adjustments of commands to fingers (modes) across cycles that stabilized total force. Fatigue caused a significant reduction in the MVC of the exercised as well as the non-exercised hand. Indices of finger enslaving (lack of individuation) increased with fatigue in both hands, although the increase was significant in the exercised hand only. In contrast to the significant effects of fatigue on MVC forces performed by the non-exercised hand, there were no comparable transfer effects on the root mean square errors during accurate force production. During one-hand tasks, both hands showed high indices of force-stabilizing synergies. These indices were larger in the left hand. Fatigue led to a general increase in synergy indices. Exercise by the left hand had stronger effects on synergy indices seen in both hands. Exercise by the right hand showed ipsilateral effects only. Smaller effects of fatigue were observed on accuracy of performance of the force-down segments of the force cycles compared to the force-up segments. For the bimanual tasks, synergies were analyzed at two hierarchical levels, two-hand (four-finger) and within-a-hand (two-finger). An increase in the synergy index with fatigue was observed at the lower (two-finger) level of the hierarchy only. We interpret the lack of effects of fatigue at the upper (two-hand) level as a consequence of a trade-off between synergies at different levels of the hierarchy. The differences between the hands are discussed within the dynamic dominance hypothesis. PMID:23182434

  3. Nearby stars to distant galaxies: TMT-ALMA synergies

    NASA Astrophysics Data System (ADS)

    Sheth, Kartik; Wilson, Christine

    2014-07-01

    Although they will probe very different wavelength regimes, significant synergies will exist for TMT and ALMA due to their capabilities for high angular resolution photometric and spectroscopic imaging. We illustrate this complementarity by examining a few specific science examples ranging from exoplanets, star forming disks in our Milky Way to black hole mass measurements in nearby galaxies to high redshift galaxy assemly. Since ALMA will be a relatively mature instrument by the end of TMT construction, we focus on synergies with the TMT first-light instruments as much as possible. We will also describe the current status and capabilities of ALMA and showcase some recent science results.

  4. Action and perception at the level of synergies.

    PubMed

    Turvey, M T

    2007-08-01

    Meeting the challenge of assembling coherent organizations of very many muscles characterizes a functional level of biological movement systems referred to as the level of muscular-articular links or synergies. The present article examines the issues confronting the forming, regulating, and ordering of synergies and the hypothesized principles, both classical and contemporary, which resolve them. A primary goal of the article is to highlight the abstractness of the concepts and tools required to understand the level's action-perception competence. Coverage is given to symmetry groups, task space, order parameters, metastability, biotensegrity, allometric scaling, and impredicative definitions. PMID:17604860

  5. Action Direction of Muscle Synergies in Three-Dimensional Force Space

    PubMed Central

    Hagio, Shota; Kouzaki, Motoki

    2015-01-01

    Redundancy in the musculoskeletal system was supposed to be simplified by muscle synergies, which modularly organize muscles. To clarify the underlying mechanisms of motor control using muscle synergies, it is important to examine the spatiotemporal contribution of muscle synergies in the task space. In this study, we quantified the mechanical contribution of muscle synergies as considering spatiotemporal correlation between the activation of muscle synergies and endpoint force fluctuations. Subjects performed isometric force generation in the three-dimensional force space. The muscle-weighting vectors of muscle synergies and their activation traces across different trials were extracted from electromyogram data using decomposing technique. We then estimated mechanical contribution of muscle synergies across each trial based on cross-correlation analysis. The contributing vectors were averaged for all trials, and the averaging was defined as action direction (AD) of muscle synergies. As a result, we extracted approximately five muscle synergies. The ADs of muscle synergies mainly depended on the anatomical functions of their weighting muscles. Furthermore, the AD of each muscle indicated the synchronous activation of muscles, which composed of the same muscle synergy. These results provide the spatiotemporal characteristics of muscle synergies as neural basis. PMID:26618156

  6. Building Synergy: The Power of High Performance Work Systems.

    ERIC Educational Resources Information Center

    Gephart, Martha A.; Van Buren, Mark E.

    1996-01-01

    Suggests that high-performance work systems create the synergy that lets companies gain and keep a competitive advantage. Identifies the components of high-performance work systems and critical action steps for implementation. Describes the results companies such as Xerox, Lever Brothers, and Corning Incorporated have achieved by using them. (JOW)

  7. Peace Education, ESD and the Earth Charter: Interconnections and Synergies

    ERIC Educational Resources Information Center

    Toh, Swee-Hin; Cawagas, Virginia Floresca

    2010-01-01

    This article provides a review of how the values and principles of the Earth Charter initiative relate to two specific innovative movements of educational transformation, namely peace education and education for sustainable development (ESD). The interconnections and synergies between these movements and the Earth Charter are highlighted.…

  8. Learning Motor Synergies by Persons with Down Syndrome

    ERIC Educational Resources Information Center

    Latash, M. L.

    2007-01-01

    Persons with Down syndrome are frequently described as "clumsy". The recent progress in the development of quantitative approaches to motor synergies has allowed researchers to move towards an understanding of "clumsiness" at the level of underlying control mechanisms. This progress has also offered an opportunity to quantify changes in motor…

  9. The Intersection of Structural and Chemical Biology - An Essential Synergy.

    PubMed

    Zuercher, William J; Elkins, Jonathan M; Knapp, Stefan

    2016-01-21

    The continual improvement in our ability to generate high resolution structural models of biological molecules has stimulated and supported innovative chemical biology projects that target increasingly challenging ligand interaction sites. In this review we outline some of the recent developments in chemical biology and rational ligand design and show selected examples that illustrate the synergy between these research areas. PMID:26933743

  10. Practice effects on intra-team synergies in football teams.

    PubMed

    Silva, Pedro; Chung, Dante; Carvalho, Thiago; Cardoso, Tiago; Davids, Keith; Araújo, Duarte; Garganta, Júlio

    2016-04-01

    Developing synchronised player movements for fluent competitive match play is a common goal for coaches of team games. An ecological dynamics approach advocates that intra-team synchronization is governed by locally created information, which specifies shared affordances responsible for synergy formation. To verify this claim we evaluated coordination tendencies in two newly-formed teams of recreational players during association football practice games, weekly, for fifteen weeks (thirteen matches). We investigated practice effects on two central features of synergies in sports teams - dimensional compression and reciprocal compensation here captured through near in-phase modes of coordination and time delays between coupled players during forward and backwards movements on field while attacking and defending. Results verified that synergies were formed and dissolved rapidly as a result of the dynamic creation of informational properties, perceived as shared affordances among performers. Practising once a week led to small improvements in the readjustment delays between co-positioning team members, enabling faster regulation of coordinated team actions. Mean values of the number of player and team synergies displayed only limited improvements, possibly due to the timescales of practice. No relationship between improvements in dimensional compression and reciprocal compensation were found for number of shots, amount of ball possession and number of ball recoveries made. Findings open up new perspectives for monitoring team coordination processes in sport. PMID:26707679

  11. Possible causes of dry pea synergy to corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dry pea improves corn yield and tolerance to weed interference compared with soybean, spring wheat, or canola as preceding crops. To understand this synergy between dry pea and corn, we examined growth and nutrient concentration of corn following dry pea or soybean in sequence. Each corn plot was ...

  12. Magnetars: recent discoveries and synergies with multi-band facilities

    NASA Astrophysics Data System (ADS)

    Rea, N.

    2016-06-01

    In this talk I will review the recent discoveries and theoretical advances in the field of highly magnetized neutron stars (aka magnetars). I will focus on the large impact that XMM-Newton has in our understanding of these extreme sources. Furthermore, I will shortly review on the multi-band emission of magnetars and on the potential synergies with other facilities.

  13. syNErgy: A Case Study in Workforce Curriculum Development

    ERIC Educational Resources Information Center

    Killingsworth, John; Grosskopf, Kevin R.

    2013-01-01

    With high unemployment and structural changes to industry, workforce development in the United States is a growing concern. Many semiskilled workers lack knowledge, skills, and abilities to be competitive for reemployment to green jobs. Nebraska's syNErgy research grant was introduced to address the training needs of unemployed and…

  14. Project SYNERGY: Software Support for Underprepared Students. Year Two Report.

    ERIC Educational Resources Information Center

    Miami-Dade Community Coll., FL. Div. of Educational Technologies.

    With funds from the International Business Machines (IBM) Corporation, Project SYNERGY was launched in January 1990 to address the problem of students entering colleges underprepared in basic skills and to make use of the tremendous potential for significant remediation through computers. Twenty-two institutions in the United States and Canada,…

  15. Project SYNERGY: Software Support for Underprepared Students. Software Implementation Report.

    ERIC Educational Resources Information Center

    Anandam, Kamala; And Others

    Miami-Dade Community College's (MDCC's) implementation and assessment of computer software as a part of Project SYNERGY, a multi-institutional project funded by the International Business Machines (IBM) Corporation designed to seek technological solutions for helping students underprepared in reading, writing and mathematics, is described in this…

  16. Hybrid MR-PET in Neuroimaging.

    PubMed

    Bisdas, S; Lá Fougere, C; Ernemann, U

    2015-10-01

    Hybrid magnetic resonance (MR)-positron emission tomography (MR-PET) is a novel technology with advantages over sequential MR and PET imaging, allowing maintain full individual diagnostic performance with negligible mutual interference between the two hardware settings. Obvious synergies between MR and PET in acquisition of anatomical, functional, and molecular information for neurological diseases into one single image pave the way for establishing clear clinical indications for hybrid MR-PET as well as addressing unmet neuroimaging needs in future clinics and research. Further developments in attenuation correction, quantification, workflow, and effective MR-PET data management might unfold the full potential of integrated multimodality imaging. PMID:26227618

  17. A novel computational framework for deducing muscle synergies from experimental joint moments

    PubMed Central

    Gopalakrishnan, Anantharaman; Modenese, Luca; Phillips, Andrew T. M.

    2014-01-01

    Prior experimental studies have hypothesized the existence of a “muscle synergy” based control scheme for producing limb movements and locomotion in vertebrates. Such synergies have been suggested to consist of fixed muscle grouping schemes with the co-activation of all muscles in a synergy resulting in limb movement. Quantitative representations of these groupings (termed muscle weightings) and their control signals (termed synergy controls) have traditionally been derived by the factorization of experimentally measured EMG. This study presents a novel approach for deducing these weightings and controls from inverse dynamic joint moments that are computed from an alternative set of experimental measurements—movement kinematics and kinetics. This technique was applied to joint moments for healthy human walking at 0.7 and 1.7 m/s, and two sets of “simulated” synergies were computed based on two different criteria (1) synergies were required to minimize errors between experimental and simulated joint moments in a musculoskeletal model (pure-synergy solution) (2) along with minimizing joint moment errors, synergies also minimized muscle activation levels (optimal-synergy solution). On comparing the two solutions, it was observed that the introduction of optimality requirements (optimal-synergy) to a control strategy solely aimed at reproducing the joint moments (pure-synergy) did not necessitate major changes in the muscle grouping within synergies or the temporal profiles of synergy control signals. Synergies from both the simulated solutions exhibited many similarities to EMG derived synergies from a previously published study, thus implying that the analysis of the two different types of experimental data reveals similar, underlying synergy structures. PMID:25520645

  18. Upper limb joint space modeling of stroke induced synergies using isolated and voluntary arm perturbations.

    PubMed

    Simkins, Matt; Al-Refai, Aimen H; Rosen, Jacob

    2014-05-01

    Among other diminished motor capabilities, survivors of a stroke often exhibit joint synergies. These synergies are stereotypically characterized by involuntary joint co-activation. With respect to the upper limbs, such synergies diminish coordination in reaching, pointing, and other daily tasks. The primary goal of this research is to model synergy and quantify it in a comprehensive and mathematically tractable form. A motion capture system was used to measure joint rotations from stroke survivors and control subjects. These data showed that joint synergies are nonunique and asymmetric. The model also provided a way to calculate joint combinations that result in maximum and minimum synergy. Beyond providing a more complete view of synergies, this approach could facilitate new ways to evaluate and treat stroke survivors. In particular, this approach may have applications in diagnostic and treatment algorithms for use in rehabilitation robots. PMID:23912501

  19. The flexion synergy, mother of all synergies and father of new models of gait

    PubMed Central

    Duysens, Jacques; De Groote, Friedl; Jonkers, Ilse

    2013-01-01

    Recently there has been a growing interest in the modular organization of leg movements, in particular those related to locomotion. One of the basic modules involves the flexion of the leg during swing and it was shown that this module is already present in neonates (Dominici et al., 2011). In this paper, we question how these finding build upon the original work by Sherrington, who proposed that the flexor reflex is the basic building block of flexion during swing phase. Similarly, the relation between the flexor reflex and the withdrawal reflex modules of Schouenborg and Weng (1994) will be discussed. It will be argued that there is large overlap between these notions on modules and the older concepts of reflexes. In addition, it will be shown that there is a great flexibility in the expression of some of these modules during gait, thereby allowing for a phase-dependent modulation of the appropriate responses. In particular, the end of the stance phase is a period when the flexor synergy is facilitated. It is proposed that this is linked to the activation of circuitry that is responsible for the generation of locomotor patterns (CPG, “central pattern generator”). More specifically, it is suggested that the responses in that period relate to the activation of a flexor burst generator. The latter structure forms the core of a new asymmetric model of the CPG. This activation is controlled by afferent input (facilitation by a broad range of afferents, suppression by load afferent input). Meanwhile, many of these physiologic features have found their way in the control of very flexible walking bipedal robots. PMID:23494365

  20. Hybrid compounds: from simple combinations to nanomachines.

    PubMed

    Müller-Schiffmann, Andreas; Sticht, Heinrich; Korth, Carsten

    2012-02-01

    The combination of two different and independently acting compounds into one covalently linked hybrid compound can convey synergy from the effects of both independently acting moieties to the new composite compound, leading to a pharmacological potency greater than the sum of each individual moiety's potencies. Here, we review a variety of such hybrid compounds, which can consist of various functional parts, molecular recognition or subcellular targeting moieties, or combinations thereof, acting either simultaneously or sequentially. Such moieties within a hybrid compound can consist of a variety of substance classes, including small organic molecules, polypeptides or nucleic acids identified either via rational molecular design or selection from libraries. Precedent for hybrid compounds comes from naturally occurring proteins and small molecules, such as botulinum toxin and bleomycin, which are secreted by micro-organisms. We review the high degree of suitability of hybrid compounds for the treatment of multifactorial diseases by simultaneously hitting several targets along an identified disease pathway. Examples are hybrid compounds against Alzheimer's disease, against the cancer-relevant phosphoinisitide-3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) and epidermal growth factor signaling cascade, or in antimalarial therapy via simultaneous hitting of different mechanisms of hemozoin formation. Molecular recognition by peptides or aptamers (recognition-specific RNA or peptide sequences) can be combined with the transport of small molecule β-sheet breakers or toxins, or targeting to ubiquitin-dependent proteolysis. The vision of molecular nanomachines is currently realized in sequentially acting modular nanotransporters, consisting of four modules including a target, a membrane and nuclear translocation sequence, as well as a drug attachment domain. Through the rational combination of existing drugs and the synergy of their effects, a rapid

  1. Evaluation of synergy in tire rubber-coal coprocessing

    SciTech Connect

    Mastral, A.M.; Mayoral, M.C.; Murillo, R.; Callen, M.; Garcia, T.; Tejero, M.P.; Torres, N.

    1998-09-01

    The tire rubber-coal synergy is evaluated through the different roles that rubber can have in coprocessing systems. For that, two different experimental designs were used: a swept fixed-bed reactor and tubing bomb minireactors. In this way, coal was coprocessed with rubber liquids from rubber pyrolysis and rubber hydrogenation, in a hydrogen atmosphere at 400 C. Coal was mixed as well with rubber in different proportions and hydrogenated at 375, 400, and 425 C, and oils obtained were characterized by thin-layer chromatography to obtain hydrocarbon type composition. Rubber behavior was compared to each of the main components of tires, and all the results indicated that the slight synergy found can be due to the small free radicals from vulcanized rubber decomposition, which are able to stabilize coal radicals to light products.

  2. Synergy between Printex nano-carbons and silver nanoparticles for sensitive estimation of antioxidant activity.

    PubMed

    Raymundo-Pereira, Paulo A; Campos, Anderson M; Prado, Thiago M; Furini, Leonardo N; Boas, Naiza V; Calegaro, Marcelo L; Machado, Sergio A S

    2016-07-01

    We report on the synthesis, characterization and applications of a Printex L6 carbon-silver hybrid nanomaterial (PC-Ag), which was obtained using a polyol method. In addition, we also highlight the use of Printex L6 nano-carbon as a much cheaper alternative to the use of carbon nanotubes and graphene. The silver nanoparticles (AgNP) were prepared directly on the surface of the Printex 6L carbon "nanocarbon" material using ethylene glycol as the reducing agent. The hybrid nanomaterial was characterized by High-angle annular dark-field transmission electron microscopy (HAADF-TEM), energy-dispersive X-ray spectroscopy (EDX), selected area electron diffraction (SAED), Raman spectroscopy and cyclic voltammetry. Optimized electrocatalytic activity on glassy carbon electrode was reached for the architecture GC/PC-Ag, the silver nanoparticles with size ranging between 1 and 2 nm were well-distributed throughout the hybrid material. The synergy between PC nano-carbons and AgNPs was verified by detection of gallic acid (GA) at a low applied potential (0.091 V vs. Ag/AgCl). GA detection was performed in a concentration range between 5.0 × 10(-7) and 8.5 × 10(-6) mol L(-1), with a detection limit of 6.63 × 10(-8) mol L(-1) (66.3 nmol L(-1)), which is considerably lower than similar devices. The approach for fabricating the reproducible GC/PC-Ag electrodes is entirely generic and may be explored for other types of (bio)sensors and devices. PMID:27216397

  3. Interpersonal synergies: static prehension tasks performed by two actors.

    PubMed

    Solnik, Stanislaw; Reschechtko, Sasha; Wu, Yen-Hsun; Zatsiorsky, Vladimir M; Latash, Mark L

    2016-08-01

    We investigated multidigit synergies stabilizing components of the resultant force vector during joint performance of a static prehension task by two persons as compared to similar tasks performed by a single person using both hands. Subjects transferred the instrumented handle from the right hand to the left hand (one-person condition) or passed that handle to another person (two-person condition) while keeping the handle's position and orientation stationary. Only three digits were involved per hand, the thumb, the index finger, and the middle finger; the forces and moments produced by the digits were measured by six-component sensors. We estimated the performance-stabilizing synergies within the uncontrolled manifold framework by quantifying the intertrial variance structure of digit forces and moments. The analysis was performed at three levels: between hands, between virtual finger and virtual thumb (imagined digits producing the same mechanical variables as the corresponding actual digits combined) produced by the two hands (in both interpersonal and intrapersonal conditions), and between the thumb and virtual finger for one hand only. Additionally, we performed correlation and phase synchronization analyses of resultant tangential forces and internal normal forces. Overall, the one-person conditions were characterized by higher amount of intertrial variance that did not affect resultant normal force components, higher internal components of normal forces, and stronger synchronization of the normal forces generated by the hands. Our observations suggest that in two-person tasks, when participants try to achieve a common mechanical outcome, the performance-stabilizing synergies depend on non-visual information exchange, possibly via the haptic and proprioceptive systems. Therefore, synergies quantified in tasks using visual feedback only may not be generalizable to more natural tasks. PMID:27021074

  4. Submillimeter Surveys with CCAT and Synergies with the TMT

    NASA Astrophysics Data System (ADS)

    Carpenter, John

    2014-07-01

    CCAT will be a 25-meter telescope for submillimeter astronomy located at 5600 meter altitude on Cerro Chajnantor in northern Chile. CCAT will combine high sensitivity, a wide field of view, and broad wavelength coverage to provide an unprecedented capability for deep, large-area multicolor submillimeter surveys. I will describe the scientific synergies between CCAT surveys and TMT, with emphasis on the exploration of galaxies at high redshift and the origin of the stellar initial mass function.

  5. Emerging and disappearing synergies in a hierarchically controlled system

    PubMed Central

    Gorniak, Stacey L.; Zatsiorsky, Vladimir M.; Latash, Mark L.

    2010-01-01

    The purpose of the study was to explore the ability of the central nervous system (CNS) to organize synergies at two levels of a hypothetical control hierarchy involved in two-hand, multi-finger tasks. We investigated indices (ΔV) of finger force co-variation across trials as reflections of synergies stabilizing the total force (FTOT). Subjects produced constant force with one or two finger-pairs (from one hand or two hands). In trials starting with one finger-pair, subjects added another finger-pair without changing FTOT. In trials starting with two finger-pairs, subjects removed one of the finger-pairs without changing FTOT. Adding or removing a finger-pair resulted in a transient drop in ΔV computed for the finger-pair that remained active throughout the trial. This drop in ΔV was seen simultaneously with force changes. Compared to the original steady-state, addition of a finger-pair led to a significant drop in ΔV at the newly established steady-state. This drop eliminated negative co-variation among finger forces that had stabilized FTOT. In contrast, in trials starting with two finger-pairs, no negative co-variation between finger forces within-a-pair was seen. Removing a finger-pair led to the emergence of negative co-variation between finger forces at the new steady-state. The ΔV index computed across two finger-pairs confirmed the existence of negative force co-variation. The emergence and disappearance of force stabilizing synergies within a finger-pair may signal limitations in the ability of the CNS in forming synergies at two different hierarchical levels. PMID:17703288

  6. Analgesic synergy between opioid and α2-adrenoceptors

    PubMed Central

    Chabot-Doré, A-J; Schuster, D J; Stone, L S; Wilcox, G L

    2015-01-01

    Opioid and α2-adrenoceptor agonists are potent analgesic drugs and their analgesic effects can synergize when co-administered. These supra-additive interactions are potentially beneficial clinically; by increasing efficacy and/or reducing the total drug required to produce sufficient pain relief, undesired side effects can be minimized. However, combination therapies of opioids and α2-adrenoceptor agonists remain underutilized clinically, in spite of a large body of preclinical evidence describing their synergistic interaction. One possible obstacle to the translation of preclinical findings to clinical applications is a lack of understanding of the mechanisms underlying the synergistic interactions between these two drug classes. In this review, we provide a detailed overview of the interactions between different opioid and α2-adrenoceptor agonist combinations in preclinical studies. These studies have identified the spinal cord as an important site of action of synergistic interactions, provided insights into which receptors mediate these interactions and explored downstream signalling events enabling synergy. It is now well documented that the activation of both μ and δ opioid receptors can produce synergy with α2-adrenoceptor agonists and that α2-adrenoceptor agonists can mediate synergy through either the α2A or the α2C adrenoceptor subtypes. Current hypotheses surrounding the cellular mechanisms mediating opioid–adrenoceptor synergy, including PKC signalling and receptor oligomerization, and the evidence supporting them are presented. Finally, the implications of these findings for clinical applications and drug discovery are discussed. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2 PMID:24641506

  7. Muscle synergy patterns as physiological markers of motor cortical damage

    PubMed Central

    Cheung, Vincent C. K.; Turolla, Andrea; Agostini, Michela; Silvoni, Stefano; Bennis, Caoimhe; Kasi, Patrick; Paganoni, Sabrina; Bonato, Paolo; Bizzi, Emilio

    2012-01-01

    The experimental findings herein reported are aimed at gaining a perspective on the complex neural events that follow lesions of the motor cortical areas. Cortical damage, whether by trauma or stroke, interferes with the flow of descending signals to the modular interneuronal structures of the spinal cord. These spinal modules subserve normal motor behaviors by activating groups of muscles as individual units (muscle synergies). Damage to the motor cortical areas disrupts the orchestration of the modules, resulting in abnormal movements. To gain insights into this complex process, we recorded myoelectric signals from multiple upper-limb muscles in subjects with cortical lesions. We used a factorization algorithm to identify the muscle synergies. Our factorization analysis revealed, in a quantitative way, three distinct patterns of muscle coordination—including preservation, merging, and fractionation of muscle synergies—that reflect the multiple neural responses that occur after cortical damage. These patterns varied as a function of both the severity of functional impairment and the temporal distance from stroke onset. We think these muscle-synergy patterns can be used as physiological markers of the status of any patient with stroke or trauma, thereby guiding the development of different rehabilitation approaches, as well as future physiological experiments for a further understanding of postinjury mechanisms of motor control and recovery. PMID:22908288

  8. Muscle synergies are consistent when pedaling under different biomechanical demands.

    PubMed

    De Marchis, C; Castronovo, A M; Bibbo, D; Schmid, M; Conforto, S

    2012-01-01

    In this study we investigate the muscle coordination underlying the execution of a pedaling exercise across different biomechanical demands, by using the muscle synergies paradigm. 9 non professional subjects performed a cycling exercise using their preferred pedaling strategy (Preferred Strategy, PS) and then, through the use of a feedback based on the presentation of a real-time index of mechanical efficiency determined by means of instrumented pedals, they were helped to optimize their pedaling technique (Effective Strategy, ES). EMG activity was recorded from 8 muscles of the dominant leg. Nonnegative Matrix Factorization was applied for the extraction of muscle synergies. 4 modules were sufficient to reconstruct the repertoire of muscle activations for all the subjects during PS condition, and these modules were found consistent across all the subjects (correlation > 83%). 5 muscle synergies were necessary for the characterization in ES condition; 4 out of these modules were shared with PS condition, and the resulting additional module appeared subject-specific. These preliminary results support the existence of a modular motor control in humans. PMID:23366633

  9. A synergy-driven approach to a myoelectric hand.

    PubMed

    Godfrey, S B; Ajoudani, A; Catalano, M; Grioli, G; Bicchi, A

    2013-06-01

    In this paper, we present the Pisa/IIT SoftHand with myoelectric control as a synergy-driven approach for a prosthetic hand. Commercially available myoelectric hands are more expensive, heavier, and less robust than their body-powered counterparts; however, they can offer greater freedom of motion and a more aesthetically pleasing appearance. The Pisa/IIT SoftHand is built on the motor control principle of synergies through which the immense complexity of the hand is simplified into distinct motor patterns. As the SoftHand grasps, it follows a synergistic path with built-in flexibility to allow grasping of a wide variety of objects with a single motor. Here we test, as a proof-of-concept, 4 myoelectric controllers: a standard controller in which the EMG signal is used only as a position reference, an impedance controller that determines both position and stiffness references from the EMG input, a standard controller with vibrotactile force feedback, and finally a combined vibrotactile-impedance (VI) controller. Four healthy subjects tested the control algorithms by grasping various objects. All controllers were sufficient for basic grasping, however the impedance and vibrotactile controllers reduced the physical and cognitive load on the user, while the combined VI mode was the easiest to use of the four. While these results need to be validated with amputees, they suggest a low-cost, robust hand employing hardware-based synergies is a viable alternative to traditional myoelectric prostheses. PMID:24187196

  10. Food synergy: an operational concept for understanding nutrition1234

    PubMed Central

    Gross, Myron D; Tapsell, Linda C

    2009-01-01

    Research and practice in nutrition relate to food and its constituents, often as supplements. In food, however, the biological constituents are coordinated. We propose that “thinking food first”' results in more effective nutrition research and policy. The concept of food synergy provides the necessary theoretical underpinning. The evidence for health benefit appears stronger when put together in a synergistic dietary pattern than for individual foods or food constituents. A review of dietary supplementation suggests that although supplements may be beneficial in states of insufficiency, the safe middle ground for consumption likely is food. Also, food provides a buffer during absorption. Constituents delivered by foods taken directly from their biological environment may have different effects from those formulated through technologic processing, but either way health benefits are likely to be determined by the total diet. The concept of food synergy is based on the proposition that the interrelations between constituents in foods are significant. This significance is dependent on the balance between constituents within the food, how well the constituents survive digestion, and the extent to which they appear biologically active at the cellular level. Many examples are provided of superior effects of whole foods over their isolated constituents. The food synergy concept supports the idea of dietary variety and of selecting nutrient-rich foods. The more we understand about our own biology and that of plants and animals, the better we will be able to discern the combinations of foods, rather than supplements, which best promote health. PMID:19279083

  11. Effect of visual and tactile feedback on kinematic synergies in the grasping hand.

    PubMed

    Patel, Vrajeshri; Burns, Martin; Vinjamuri, Ramana

    2016-08-01

    The human hand uses a combination of feedforward and feedback mechanisms to accomplish high degree of freedom in grasp control efficiently. In this study, we used a synergy-based control model to determine the effect of sensory feedback on kinematic synergies in the grasping hand. Ten subjects performed two types of grasps: one that included feedback (real) and one without feedback (memory-guided), at two different speeds (rapid and natural). Kinematic synergies were extracted from rapid real and rapid memory-guided grasps using principal component analysis. Synergies extracted from memory-guided grasps revealed greater preservation of natural inter-finger relationships than those found in corresponding synergies extracted from real grasps. Reconstruction of natural real and natural memory-guided grasps was used to test performance and generalizability of synergies. A temporal analysis of reconstruction patterns revealed the differing contribution of individual synergies in real grasps versus memory-guided grasps. Finally, the results showed that memory-guided synergies could not reconstruct real grasps as accurately as real synergies could reconstruct memory-guided grasps. These results demonstrate how visual and tactile feedback affects a closed-loop synergy-based motor control system. PMID:26660896

  12. Muscle synergies during a single-leg drop-landing in boys and girls.

    PubMed

    Kipp, Kristof; Pfeiffer, Ron; Sabick, Michelle; Harris, Chad; Sutter, Jeanie; Kuhlman, Seth; Shea, Kevin

    2014-04-01

    The purpose of this study was to investigate muscle activation patterns during a landing task in boys and girls through the use of muscle synergies. Electromyographical data from six lower extremity muscles were collected from 11 boys and 16 girls while they performed single-leg drop-landings. Electromyographical data from six leg muscles were rectified, smoothed, and normalized to maximum dynamic muscle activity during landing. Data from 100 ms before to 100 ms after touchdown were submitted to factor analyses to extract muscle synergies along with the associated activation and weighing coefficients. Boys and girls both used three muscle synergies. The activation coefficients of these synergies captured muscle activity during the prelanding, touchdown, and postlanding phases of the single-leg drop-landing. Analysis of the weighing coefficients indicated that within the extracted muscle synergies the girls emphasized activation of the medial hamstring muscle during the prelanding and touchdown synergy whereas boys emphasized activation of the vastus medialis during the postlanding synergy. Although boys and girls use similar muscle synergies during single-leg drop-landings, they differed in which muscles were emphasized within these synergies. The observed differences in aspects related to the muscle synergies during landing may have implications with respect to knee injury risk. PMID:24145947

  13. Quantitative evaluation of muscle synergy models: a single-trial task decoding approach

    PubMed Central

    Delis, Ioannis; Berret, Bastien; Pozzo, Thierry; Panzeri, Stefano

    2013-01-01

    Muscle synergies, i.e., invariant coordinated activations of groups of muscles, have been proposed as building blocks that the central nervous system (CNS) uses to construct the patterns of muscle activity utilized for executing movements. Several efficient dimensionality reduction algorithms that extract putative synergies from electromyographic (EMG) signals have been developed. Typically, the quality of synergy decompositions is assessed by computing the Variance Accounted For (VAF). Yet, little is known about the extent to which the combination of those synergies encodes task-discriminating variations of muscle activity in individual trials. To address this question, here we conceive and develop a novel computational framework to evaluate muscle synergy decompositions in task space. Unlike previous methods considering the total variance of muscle patterns (VAF based metrics), our approach focuses on variance discriminating execution of different tasks. The procedure is based on single-trial task decoding from muscle synergy activation features. The task decoding based metric evaluates quantitatively the mapping between synergy recruitment and task identification and automatically determines the minimal number of synergies that captures all the task-discriminating variability in the synergy activations. In this paper, we first validate the method on plausibly simulated EMG datasets. We then show that it can be applied to different types of muscle synergy decomposition and illustrate its applicability to real data by using it for the analysis of EMG recordings during an arm pointing task. We find that time-varying and synchronous synergies with similar number of parameters are equally efficient in task decoding, suggesting that in this experimental paradigm they are equally valid representations of muscle synergies. Overall, these findings stress the effectiveness of the decoding metric in systematically assessing muscle synergy decompositions in task space. PMID

  14. Consequences of biomechanically constrained tasks in the design and interpretation of synergy analyses

    PubMed Central

    Tresch, Matthew C.; Perreault, Eric J.

    2015-01-01

    Matrix factorization algorithms are commonly used to analyze muscle activity and provide insight into neuromuscular control. These algorithms identify low-dimensional subspaces, commonly referred to as synergies, which can describe variation in muscle activity during a task. Synergies are often interpreted as reflecting underlying neural control; however, it is unclear how these analyses are influenced by biomechanical and task constraints, which can also lead to low-dimensional patterns of muscle activation. The aim of this study was to evaluate whether commonly used algorithms and experimental methods can accurately identify synergy-based control strategies. This was accomplished by evaluating synergies from five common matrix factorization algorithms using muscle activations calculated from 1) a biomechanically constrained task using a musculoskeletal model and 2) without task constraints using random synergy activations. Algorithm performance was assessed by calculating the similarity between estimated synergies and those imposed during the simulations; similarities ranged from 0 (random chance) to 1 (perfect similarity). Although some of the algorithms could accurately estimate specified synergies without biomechanical or task constraints (similarity >0.7), with these constraints the similarity of estimated synergies decreased significantly (0.3–0.4). The ability of these algorithms to accurately identify synergies was negatively impacted by correlation of synergy activations, which are increased when substantial biomechanical or task constraints are present. Increased variability in synergy activations, which can be captured using robust experimental paradigms that include natural variability in motor activation patterns, improved identification accuracy but did not completely overcome effects of biomechanical and task constraints. These results demonstrate that a biomechanically constrained task can reduce the accuracy of estimated synergies and highlight

  15. Synergy: A language and framework for robot design

    NASA Astrophysics Data System (ADS)

    Katragadda, Lalitesh Kumar

    Due to escalation in complexity, capability and application, robot design is increasingly difficult. A design environment can automate many design tasks, relieving the designer's burden. Prior to robot development, designers compose a robot from existing or custom developed components, simulate performance, optimize configuration and parameters, and write software for the robot. Robot designers customize these facets to the robot using a variety of software ranging from spreadsheets to C code to CAD tools. Valuable resources are expended, and very little of this expertise and development is reusable. This research begins with the premise that a language to comprehensively represent robots is lacking and that the aforementioned design tasks can be automated once such a language exists. This research proposes and demonstrates the following thesis: "A language to represent robots, along with a framework to generate simulations, optimize designs and generate control software, increases the effectiveness of design." Synergy is the software developed in this research to reflect this philosophy. Synergy was prototyped and demonstrated in the context of lunar rover design, a challenging real-world problem with multiple requirements and a broad design space. Synergy was used to automatically optimize robot parameters and select parts to generate effective designs, while meeting constraints of the embedded components and sub-systems. The generated designs are superior in performance and consistency when compared to designs by teams of designers using the same knowledge. Using a single representation, multiple designs are generated for four distinct lunar exploration objectives. Synergy uses the same representation to auto-generate landing simulations and simultaneously generate control software for the landing. Synergy consists of four software agents. A database and spreadsheet agent compiles the design and component information, generating component interconnections and

  16. Impacts of Synergy-505 on the Functional Response and Behavior of the Reduviid Bug, Rhynocoris marginatus

    PubMed Central

    Ambrose, D. P.; Rajan, S. J.; Raja, J. M.

    2010-01-01

    The impact of the insecticide, Synergy-505 (chlorpyrifos 50% and cypermethrin 5% E.C), on the functional response, predatory behavior, and mating behavior of a non-target reduviid, Rhynocoris marginatus (Fabricius) (Hemiptera: Reduviidae), a potential biological control agent, were studied. Though both normal and Synergy-505-exposed R. marginatus exhibited Holling's type II curvilinear functional response, Synergy-505 caused a less pronounced type II functional response with reduced numbers of prey killed, attack rate, searching time, and prolonged handling time in 4th and 5th nymphal instars and adult males and females reflecting reduced predatory potential. Synergy-505 also delayed the predatory and mating events. The impacts of Synergy-505 on functional response, predatory behavior, and mating behavior were more evident at higher concentrations of Synergy-505. PMID:21265616

  17. The number and choice of muscles impact the results of muscle synergy analyses

    PubMed Central

    Steele, Katherine M.; Tresch, Matthew C.; Perreault, Eric J.

    2013-01-01

    One theory for how humans control movement is that muscles are activated in weighted groups or synergies. Studies have shown that electromyography (EMG) from a variety of tasks can be described by a low-dimensional space thought to reflect synergies. These studies use algorithms, such as nonnegative matrix factorization, to identify synergies from EMG. Due to experimental constraints, EMG can rarely be taken from all muscles involved in a task. However, it is unclear if the choice of muscles included in the analysis impacts estimated synergies. The aim of our study was to evaluate the impact of the number and choice of muscles on synergy analyses. We used a musculoskeletal model to calculate muscle activations required to perform an isometric upper-extremity task. Synergies calculated from the activations from the musculoskeletal model were similar to a prior experimental study. To evaluate the impact of the number of muscles included in the analysis, we randomly selected subsets of between 5 and 29 muscles and compared the similarity of the synergies calculated from each subset to a master set of synergies calculated from all muscles. We determined that the structure of synergies is dependent upon the number and choice of muscles included in the analysis. When five muscles were included in the analysis, the similarity of the synergies to the master set was only 0.57 ± 0.54; however, the similarity improved to over 0.8 with more than ten muscles. We identified two methods, selecting dominant muscles from the master set or selecting muscles with the largest maximum isometric force, which significantly improved similarity to the master set and can help guide future experimental design. Analyses that included a small subset of muscles also over-estimated the variance accounted for (VAF) by the synergies compared to an analysis with all muscles. Thus, researchers should use caution using VAF to evaluate synergies when EMG is measured from a small subset of muscles

  18. Effects of unilateral stroke on multi-finger synergies and their feed-forward adjustments.

    PubMed

    Jo, H J; Maenza, C; Good, D C; Huang, X; Park, J; Sainburg, R L; Latash, M L

    2016-04-01

    We explored the changes in multi-finger synergies in patients after a single cortical stroke with mild motor impairments. We hypothesized that both synergy indices and anticipatory synergy adjustments prior to the initiation of a self-paced quick action would be diminished in the patients compared to age-matched controls. The patients with history of cortical stroke, and age-matched controls (n=12 in each group) performed one-finger and multi-finger accurate force production tasks involving both steady-state and quick force pulse production. Finger interdependence (enslaving) and multi-finger synergies stabilizing total force were quantified. The stroke patients showed lower maximal finger forces, in particular in the contralesional hand, which also showed increased enslaving indices. Multi-finger synergies during steady-state force production were, however, unchanged after stroke. In contrast, a drop in the synergy index prior to the force pulse generation was significantly delayed in the stroke patients. Our results show that mild cortical stroke leads to no significant changes in multifinger synergies, but there is impairment in feed-forward adjustments of the synergies prior to a quick action, a drop in the maximal force production, and an increase in enslaving. We conclude that studies of synergies reveal two aspects of synergic control differentially affected by cortical stroke. PMID:26828408

  19. A Methodology to Measure Synergy Among Energy-Efficiency Programs at the Program Participant Level

    SciTech Connect

    Tonn, B.E.

    2003-11-14

    This paper presents a methodology designed to measure synergy among energy-efficiency programs at the program participant level (e.g., households, firms). Three different definitions of synergy are provided: strong, moderate, and weak. Data to measure synergy can be collected through simple survey questions. Straightforward mathematical techniques can be used to estimate the three types of synergy and explore relative synergistic impacts of different subsets of programs. Empirical research is needed to test the concepts and methods and to establish quantitative expectations about synergistic relationships among programs. The market for new energy-efficient motors is the context used to illustrate all the concepts and methods in this paper.

  20. Force-stabilizing synergies in motor tasks involving two actors.

    PubMed

    Solnik, Stanislaw; Reschechtko, Sasha; Wu, Yen-Hsun; Zatsiorsky, Vladimir M; Latash, Mark L

    2015-10-01

    We investigated the ability of two persons to produce force-stabilizing synergies in accurate multi-finger force production tasks under visual feedback on the total force only. The subjects produced a time profile of total force (the sum of two hand forces in one-person tasks and the sum of two subject forces in two-person tasks) consisting of a ramp-up, steady-state, and ramp-down segments; the steady-state segment was interrupted in the middle by a quick force pulse. Analyses of the structure of inter-trial finger force variance, motor equivalence, anticipatory synergy adjustments (ASAs), and the unintentional drift of the sharing pattern were performed. The two-person performance was characterized by a dramatically higher amount of inter-trial variance that did not affect total force, higher finger force deviations that did not affect total force (motor equivalent deviations), shorter ASAs, and larger drift of the sharing pattern. The rate of sharing pattern drift correlated with the initial disparity between the forces produced by the two persons (or two hands). The drift accelerated following the quick force pulse. Our observations show that sensory information on the task-specific performance variable is sufficient for the organization of performance-stabilizing synergies. They suggest, however, that two actors are less likely to follow a single optimization criterion as compared to a single performer. The presence of ASAs in the two-person condition might reflect fidgeting by one or both of the subjects. We discuss the characteristics of the drift in the sharing pattern as reflections of different characteristic times of motion within the subspaces that affect and do not affect salient performance variables. PMID:26105756

  1. Knowledge-analytics synergy in Clinical Decision Support.

    PubMed

    Slonim, Noam; Carmeli, Boaz; Goldsteen, Abigail; Keller, Oliver; Kent, Carmel; Rinott, Ruty

    2012-01-01

    Clinical Decision Support (CDS) systems hold tremendous potential for improving patient care. Most existing systems are knowledge-based tools that rely on relatively simple rules. More recent approaches rely on analytics techniques to automatically mine EHR data to reveal meaningful insights. Here, we propose the Knowledge-Analytics Synergy paradigm for CDS, in which we synergistically combine existing relevant knowledge with analytics applied to EHR data. We propose a framework for implementing such a paradigm and demonstrate its principles over real-world clinical and genomic data of hypertensive patients. PMID:22874282

  2. Cyclization Cascade of Allenyl Azides: Synergy Between Theory and Experiment

    PubMed Central

    Faza, Olalla Nieto; Feldman, Ken S.; López, Carlos Silva

    2012-01-01

    Collaborative work between experimentalists and computational chemists have demonstrated a stong synergy which allowed the rationalization of allenyl azide chemistry and permited the development of an efficient synthetic tool aimed at the preparation of several alkaloids. Saturated allenyl azides undergo a reaction cascade involving key diradical intermediates that follow the Curtin-Hammett model whereas unsaturated allenyl azides form indolidene intermediates that furnish the final indole products via electrocyclic ring closure events taking place out of the Curtin-Hammett regime. The regiochemistry of the reaction cascade with the latter substrates can be manipulated by Cu(I) addition to the reaction mixture. PMID:22347808

  3. Continuous quality improvement and medical informatics: the convergent synergy.

    PubMed

    Werth, G R; Connelly, D P

    1992-01-01

    Continuous quality improvement (CQI) and medical informatics specialists need to converge their efforts to create synergy for improving health care. Health care CQI needs medical informatics' expertise and technology to build the information systems needed to manage health care organizations according to quality improvement principles. Medical informatics needs CQI's philosophy and methods to build health care information systems that can evolve to meet the changing needs of clinicians and other stakeholders. This paper explores the philosophical basis for convergence of CQI and medical informatics efforts, and then examines a clinical computer workstation development project that is applying a combined approach. PMID:1482948

  4. Muscle synergies as a predictive framework for the EMG patterns of new hand postures

    NASA Astrophysics Data System (ADS)

    Ajiboye, A. B.; Weir, R. F.

    2009-06-01

    Synchronous muscle synergies have been suggested as a framework for dimensionality reduction in muscle coordination. Many studies have shown that synergies form a descriptive framework for a wide variety of tasks. We examined if a muscle synergy framework could accurately predict the EMG patterns associated with untrained static hand postures, in essence, if they formed a predictive framework. Hand and forearm muscle activities were recorded while subjects statically mimed 33 postures of the American Sign Language alphabet. Synergies were extracted from a subset of training postures using non-negative matrix factorization and used to predict the EMG patterns of the remaining postures. Across the subject population, as few as 11 postures could form an eight-dimensional synergy framework that allowed for at least 90% prediction of the EMG patterns of all 33 postures, including trial-to-trial variations. Synergies were quite robust despite using different postures in the training set, and also despite using a varied number of postures. Estimated synergies were categorized into those which were subject-specific and those which were general to the population. Population synergies were sparser than the subject-specific synergies, typically being dominated by a single muscle. Subject-specific synergies were more balanced in the coactivation of multiple muscles. We suggest as a result that global muscle coordination may be a combination of higher order control of robust subject-specific muscle synergies and lower order control of individuated muscles, and that this control paradigm may be useful in the control of EMG-based technologies, such as artificial limbs and functional electrical stimulation systems.

  5. Muscle synergies as a predictive framework for the EMG patterns of new hand postures

    PubMed Central

    Ajiboye, A B; Weir, R F

    2011-01-01

    Synchronous muscle synergies have been suggested as a framework for dimensionality reduction in muscle coordination. Many studies have shown that synergies form a descriptive framework for a wide variety of tasks. We examined if a muscle synergy framework could accurately predict the EMG patterns associated with untrained static hand postures, in essence, if they formed a predictive framework. Hand and forearm muscle activities were recorded while subjects statically mimed 33 postures of the American Sign Language alphabet. Synergies were extracted from a subset of training postures using non-negative matrix factorization and used to predict the EMG patterns of the remaining postures. Across the subject population, as few as 11 postures could form an eight-dimensional synergy framework that allowed for at least 90% prediction of the EMG patterns of all 33 postures, including trial-to-trial variations. Synergies were quite robust despite using different postures in the training set, and also despite using a varied number of postures. Estimated synergies were categorized into those which were subject-specific and those which were general to the population. Population synergies were sparser than the subject-specific synergies, typically being dominated by a single muscle. Subject-specific synergies were more balanced in the coactivation of multiple muscles. We suggest as a result that global muscle coordination may be a combination of higher order control of robust subject-specific muscle synergies and lower order control of individuated muscles, and that this control paradigm may be useful in the control of EMG-based technologies, such as artificial limbs and functional electrical stimulation systems. PMID:19436081

  6. Food synergy: the key to a healthy diet.

    PubMed

    Jacobs, David R; Tapsell, Linda C

    2013-05-01

    Food synergy is the concept that the non-random mixture of food constituents operates in concert for the life of the organism eaten and presumably for the life of the eater. Isolated nutrients have been extensively studied in well-designed, long-term, large randomised clinical trials, typically with null and sometimes with harmful effects. Therefore, although nutrient deficiency is a known phenomenon, serious for the sufferer, and curable by taking the isolated nutrient, the effect of isolated nutrients or other chemicals derived from food on chronic disease, when that chemical is not deficient, may not have the same beneficial effect. It appears that the focus on nutrients rather than foods is in many ways counterproductive. This observation is the basis for the argument that nutrition research should focus more strongly on foods and on dietary patterns. Unlike many dietary phenomena in nutritional epidemiology, diet pattern appears to be highly correlated over time within person. A consistent and robust conclusion is that certain types of beneficial diet patterns, notably described with words such as 'Mediterranean' and 'prudent', or adverse patterns, often described by the word 'Western', predict chronic disease. Food is much more complex than drugs, but essentially uninvestigated as food or pattern. The concept of food synergy leads to new thinking in nutrition science and can help to forge rational nutrition policy-making and to determine future nutrition research strategies. PMID:23312372

  7. Synergy in practice: caring for victims of intimate partner violence.

    PubMed

    Cox, Erin

    2003-01-01

    Intimate partner violence (IPV) is a significantly prevalent health issue that creates devastating effects for victims, their families, and the community IPV extends across social, religious, economical, geographical, and cultural groups. IPV has public health implications that affect current victims and may impact future generations. While all people are at risk for IPV, women are 5 times more likely to be victimized. Despite all of the literature regarding IPV, there is still a compliance issue regarding screening for IPV in health care settings. Utilizing the Synergy Model of Nursing Practice, this article demonstrates the care of victims of IPV by the clinical nurse specialist. The Synergy Model framework is described, and correlated with IPV The clinical nurse specialist plays a unique role that can improve patient outcomes through many domains including expert clinical practice, role modeling, education, global systems thinking, research, consultation, and holistic approaches to care. Current state of the science practice techniques and barriers to screening are discussed. The summary highlights suggestions for future research. PMID:14604131

  8. Synergy between low and high energy radical femtochemistry

    NASA Astrophysics Data System (ADS)

    Gauduel, Y. A.

    2011-01-01

    The deleterious effects of ionizing radiation on integrated biological targets being dependent on the spatio-temporal distribution of short-lived radical processes, a thorough knowledge of these early events requires a real-time probing in the range 10-15 - 10-10 s. This manuscript review is focused on the synergy that exists between low (1-10 eV) and high (MeV) energy radiation femtochemistry (LERF, HERF respectively). The synergy remains crucial for the investigation of primary radical processes that take place within the prethermal regime of low energy secondary electrons. The quantum character of very-short lived electron in a prehydrated configuration provides a unique sub-nanometric probe to spatially explore some early radiation-induced biomolecular damage. This approach would foreshadow the development of innovative applications for spatio-temporal radiation biology such as, i) a highly-selective pro-drug activation using well-defined quantum states of short-lived radicals, ii) the real-time nanodosimetry in biologically relevant environments, and iii) the ultrashort irradiation of living cells.

  9. Discovering Pair-wise Synergies in Microarray Data

    PubMed Central

    Chen, Yuan; Cao, Dan; Gao, Jun; Yuan, Zheming

    2016-01-01

    Informative gene selection can have important implications for the improvement of cancer diagnosis and the identification of new drug targets. Individual-gene-ranking methods ignore interactions between genes. Furthermore, popular pair-wise gene evaluation methods, e.g. TSP and TSG, are helpless for discovering pair-wise interactions. Several efforts to discover pair-wise synergy have been made based on the information approach, such as EMBP and FeatKNN. However, the methods which are employed to estimate mutual information, e.g. binarization, histogram-based and KNN estimators, depend on known data or domain characteristics. Recently, Reshef et al. proposed a novel maximal information coefficient (MIC) measure to capture a wide range of associations between two variables that has the property of generality. An extension from MIC(X; Y) to MIC(X1; X2; Y) is therefore desired. We developed an approximation algorithm for estimating MIC(X1; X2; Y) where Y is a discrete variable. MIC(X1; X2; Y) is employed to detect pair-wise synergy in simulation and cancer microarray data. The results indicate that MIC(X1; X2; Y) also has the property of generality. It can discover synergic genes that are undetectable by reference feature selection methods such as MIC(X; Y) and TSG. Synergic genes can distinguish different phenotypes. Finally, the biological relevance of these synergic genes is validated with GO annotation and OUgene database. PMID:27470995

  10. Discovering Pair-wise Synergies in Microarray Data.

    PubMed

    Chen, Yuan; Cao, Dan; Gao, Jun; Yuan, Zheming

    2016-01-01

    Informative gene selection can have important implications for the improvement of cancer diagnosis and the identification of new drug targets. Individual-gene-ranking methods ignore interactions between genes. Furthermore, popular pair-wise gene evaluation methods, e.g. TSP and TSG, are helpless for discovering pair-wise interactions. Several efforts to discover pair-wise synergy have been made based on the information approach, such as EMBP and FeatKNN. However, the methods which are employed to estimate mutual information, e.g. binarization, histogram-based and KNN estimators, depend on known data or domain characteristics. Recently, Reshef et al. proposed a novel maximal information coefficient (MIC) measure to capture a wide range of associations between two variables that has the property of generality. An extension from MIC(X; Y) to MIC(X1; X2; Y) is therefore desired. We developed an approximation algorithm for estimating MIC(X1; X2; Y) where Y is a discrete variable. MIC(X1; X2; Y) is employed to detect pair-wise synergy in simulation and cancer microarray data. The results indicate that MIC(X1; X2; Y) also has the property of generality. It can discover synergic genes that are undetectable by reference feature selection methods such as MIC(X; Y) and TSG. Synergic genes can distinguish different phenotypes. Finally, the biological relevance of these synergic genes is validated with GO annotation and OUgene database. PMID:27470995

  11. Supersite synergies improve volcanic SO2 flux monitoring

    NASA Astrophysics Data System (ADS)

    Burton, Michael; Di Muro, Andrea

    2014-05-01

    Both the Etna, Italy, volcano and Piton de la Fournaise (PdF), France, volcano Supersites are monitored with networks of scanning UV spectrometers. An ongoing collaboration between INGV and IPGP researchers has led to a dynamic technology transfer of novel new data analysis procedures to both networks. This new approach has been custom built to account for the particularities of both Supersites. For the Etna Supersite, the large, continuous gas emission, wide plumes and high plume height produce significant challenges for automatic networks of scanning UV spectrometers, due to the lack of a clear sky spectrum and light dilution effects. The novel approach presented here addresses both these issues. In the case of the PdF Supersite, negligible SO2 efflux is observed apart from immediately before, during and after volcanic eruptions. This necessitates a very sensitive and precise automatic analysis in order to detect the first whiffs of SO2 which act as a precursor to eruptive activity. Exactly such a solution has been developed and is demonstrated here. The technology transfer between these two Supersites promotes synergistic advantages, improving the monitoring capacity at both sites. However, until now such synergies have come about exclusively through local support from each site and the initiative of individual researchers. The full potential of such synergies can be greatly enhanced in the future if they are fully recognised and supported within the context of the Supersite initiative.

  12. Synergy between the antinociceptive effects of morphine and NSAIDs.

    PubMed

    Miranda, H F; Silva, E; Pinardi, G

    2004-05-01

    The intraperitoneal administration of morphine, diclofenac, ketoprofen, meloxicam, metamizol, paracetamol and piroxicam induced dose-dependent antinociception in mice tested with the acetic acid writhing test. The isobolographic analysis of the simultaneous intraperitoneal administration of fractions of the ED50's of morphine with each nonsteroidal anti-inflammatory drug (NSAID) demonstrated the existence of a supra-additive interaction (synergy). The selective antagonist of micro -opioid receptors naltrexone partially reversed the supra-additive interactions to additive interactions; however, the combinations of morphine/metamizol and morphine/paracetamol were completely antagonized, resulting in subadditive interactions. The selective antagonist of delta-opioid receptors naltrindole failed to significantly attenuate the combinations of morphine with ketoprofen, meloxicam and piroxicam, but decreased the activity of the combinations of morphine with diclofenac, metamizol and paracetamol, transforming the interactions from supra-additive to additive. Nor-binaltorphimine was used to evaluate the involvement of kappa-opioid receptors. Nor-binaltorphimine did not modify the supra-additive interaction of morphine and NSAIDs and the additive interaction of the co-administration of morphine and metamizol. The synergy between morphine and NSAIDs could be related to different pathways of pain transmission, probably related to the different intracellular signal transduction mechanisms of action of opioid and non-opioid agents. PMID:15213733

  13. Synergy 3000 CCS{trademark}: A new precision cleaning agent

    SciTech Connect

    Hand, T.; Bohnert, G.; Carter, R.; Flink, F.; Powers, M.

    1995-11-01

    Some of the semiaqueous cleaners in use employ terpenes as the cleaning agent, usually followed by a water rinse to remove the cleaner. Because terpenes are not miscible in water, these cleaners require the addition of surfactant to facilitate the water rinsing step, complicating recycling of the cleaner for reuse. A new critical cleaning solvent (CCS), named Synergy 3000 CCS{trademark} is a proprietary blend of terpene and heterocyclic alcohol solvents formulated to remove polar and nonpolar contaminants such as rosin fluxes, machining oils, greases, waxes, tape adhesive residue and handling soils from electrical and mechanical components and assemblies. It is a high purity, low odor solvent that does not require surfactants for water rinsing, and is derived from naturally and annually renewable resources. It demonstrates a high loading capacity for soils, grease, and contaminants and is compatible with a wide range of engineering materials commonly used in electronics applications. All of its components are biodegradable, are approved as food additives, and have no known human health effects. It has been formulated to have a higher flash point than citrus terpenes and flammable alcohols, and can be recycled via distillation. This paper presents some of the tests and evaluations that were performed during the development of Synergy 3000 CCS{trademark}, hereafter referred to as CCS, as well as current and potential applications for the solvent.

  14. Force feedback reinforces muscle synergies in insect legs.

    PubMed

    Zill, Sasha N; Chaudhry, Sumaiya; Büschges, Ansgar; Schmitz, Josef

    2015-11-01

    The nervous system solves complex biomechanical problems by activating muscles in modular, synergist groups. We have studied how force feedback in substrate grip is integrated with effects of sense organs that monitor support and propulsion in insects. Campaniform sensilla are mechanoreceptors that encode forces as cuticular strains. We tested the hypothesis that integration of force feedback from receptors of different leg segments during grip occurs through activation of specific muscle synergies. We characterized the effects of campaniform sensilla of the feet (tarsi) and proximal segments (trochanter and femur) on activities of leg muscles in stick insects and cockroaches. In both species, mechanical stimulation of tarsal sensilla activated the leg muscle that generates substrate grip (retractor unguis), as well as proximal leg muscles that produce inward pull (tibial flexor) and support/propulsion (trochanteral depressor). Stimulation of campaniform sensilla on proximal leg segments activated the same synergistic group of muscles. In stick insects, the effects of proximal receptors on distal leg muscles changed and were greatly enhanced when animals made active searching movements. In insects, the task-specific reinforcement of muscle synergies can ensure that substrate adhesion is rapidly established after substrate contact to provide a stable point for force generation. PMID:26193626

  15. A model-based approach to predict muscle synergies using optimization: application to feedback control

    PubMed Central

    Sharif Razavian, Reza; Mehrabi, Naser; McPhee, John

    2015-01-01

    This paper presents a new model-based method to define muscle synergies. Unlike the conventional factorization approach, which extracts synergies from electromyographic data, the proposed method employs a biomechanical model and formally defines the synergies as the solution of an optimal control problem. As a result, the number of required synergies is directly related to the dimensions of the operational space. The estimated synergies are posture-dependent, which correlate well with the results of standard factorization methods. Two examples are used to showcase this method: a two-dimensional forearm model, and a three-dimensional driver arm model. It has been shown here that the synergies need to be task-specific (i.e., they are defined for the specific operational spaces: the elbow angle and the steering wheel angle in the two systems). This functional definition of synergies results in a low-dimensional control space, in which every force in the operational space is accurately created by a unique combination of synergies. As such, there is no need for extra criteria (e.g., minimizing effort) in the process of motion control. This approach is motivated by the need for fast and bio-plausible feedback control of musculoskeletal systems, and can have important implications in engineering, motor control, and biomechanics. PMID:26500530

  16. Intra-Personal and Inter-Personal Kinetic Synergies During Jumping

    PubMed Central

    Slomka, Kajetan; Juras, Grzegorz; Sobota, Grzegorz; Furmanek, Mariusz; Rzepko, Marian; Latash, Mark L.

    2015-01-01

    We explored synergies between two legs and two subjects during preparation for a long jump into a target. Synergies were expected during one-person jumping. No such synergies were expected between two persons jumping in parallel without additional contact, while synergies were expected to emerge with haptic contact and become stronger with strong mechanical contact. Subjects performed jumps either alone (each foot standing on a separate force platform) or in dyads (parallel to each other, each person standing on a separate force platform) without any contact, with haptic contact, and with strong coupling. Strong negative correlations between pairs of force variables (strong synergies) were seen in the vertical force in one-person jumps and weaker synergies in two-person jumps with the strong contact. For other force variables, only weak synergies were present in one-person jumps and no negative correlations between pairs of force variable for two-person jumps. Pairs of moment variables from the two force platforms at steady state showed positive correlations, which were strong in one-person jumps and weaker, but still significant, in two-person jumps with the haptic and strong contact. Anticipatory synergy adjustments prior to action initiation were observed in one-person trials only. We interpret the different results for the force and moment variables at steady state as reflections of postural sway. PMID:26839608

  17. The relationship between the flexion synergy and stretch reflexes in individuals with chronic hemiparetic stroke.

    PubMed

    McPherson, Jacob G; Stienen, Arno H A; Drogos, Justin M; Dewald, Julius P A

    2011-01-01

    This study utilized a novel robotic device, the ACT-4D, to investigate the relationship between the flexion synergy and stretch reflexes in individuals with chronic hemiparetic stroke. Because the flexion synergy influences the amount of elbow flexor muscle activation present in the paretic limb during tasks requiring shoulder abduction loading, it was hypothesized that stretch reflexes may be modulated by expression of this abnormal muscle coactivation pattern. To test this hypothesis, the ACT-4D was used to enable 10 individuals with chronic hemiparetic stroke to generate varying amounts of shoulder abduction torque while concurrently receiving elbow extension position perturbations. It was found that increased expression of the flexion synergy led to greater reflex amplitudes as well as lower reflex velocity thresholds. The physiological basis of the flexion synergy is briefly discussed, as are the implications of the flexion synergy and stretch reflexes for purposeful movement. PMID:22275712

  18. Alterations in upper limb muscle synergy structure in chronic stroke survivors

    PubMed Central

    Rymer, William Z.; Perreault, Eric J.; Yoo, Seng Bum; Beer, Randall F.

    2013-01-01

    Previous studies in neurologically intact subjects have shown that motor coordination can be described by task-dependent combinations of a few muscle synergies, defined here as a fixed pattern of activation across a set of muscles. Arm function in severely impaired stroke survivors is characterized by stereotypical postural and movement patterns involving the shoulder and elbow. Accordingly, we hypothesized that muscle synergy composition is altered in severely impaired stroke survivors. Using an isometric force matching protocol, we examined the spatial activation patterns of elbow and shoulder muscles in the affected arm of 10 stroke survivors (Fugl-Meyer <25/66) and in both arms of six age-matched controls. Underlying muscle synergies were identified using non-negative matrix factorization. In both groups, muscle activation patterns could be reconstructed by combinations of a few muscle synergies (typically 4). We did not find abnormal coupling of shoulder and elbow muscles within individual muscle synergies. In stroke survivors, as in controls, two of the synergies were comprised of isolated activation of the elbow flexors and extensors. However, muscle synergies involving proximal muscles exhibited consistent alterations following stroke. Unlike controls, the anterior deltoid was coactivated with medial and posterior deltoids within the shoulder abductor/extensor synergy and the shoulder adductor/flexor synergy in stroke was dominated by activation of pectoralis major, with limited anterior deltoid activation. Recruitment of the altered shoulder muscle synergies was strongly associated with abnormal task performance. Overall, our results suggest that an impaired control of the individual deltoid heads may contribute to poststroke deficits in arm function. PMID:23155178

  19. Actinide incineration in fusion-fission hybrid-A model nuclear synergy

    NASA Astrophysics Data System (ADS)

    Taczanowski, Stefan

    2012-06-01

    The alliance of fusion with fission is a cause worthy of great efforts, as being able to ease (if not even to solve) serious problems that both these forms of nuclear energy are facing. Very high investment costs caused by tokamak enormous size, material consumption and difficult technology put in doubt whether alone the minute demand for fuel raw material (Li) and lack of danger of uncontrolled supercriticality prove sufficient for making it competitive. Preliminary evaluations demonstrated that a radical shift of energy production i.e. the energy gain from plasma to fission blanket is feasible [1]. A reduction in the fusion component to about 2% at given system power allows for a radical drop in plasma Q down to the values of ˜0.2-0.3 achievable in small systems [2] (e.g. mirrors) of sizes comparable to fission reactors. As a result in a Fusion-Driven Actinide Incinerator (FDI) both radiations from the plasma: corpuscular (i.e. neutrons and ions) and photons are drastically reduced. Thus are too, first of all - the neutron induced radiation damage: DPA and gas production, then plasma-wall interactions. The fundamental safety of the system has been proved by simulation of its collapse that has shown preservation its subcriticality. Summarizing, all the above problems may be solved with synergic union of fusion with fission embodied in the concept of FDI - small and less expensive.

  20. Hierarchical nanostructure and synergy of multimolecular signalling complexes.

    PubMed

    Sherman, Eilon; Barr, Valarie A; Merrill, Robert K; Regan, Carole K; Sommers, Connie L; Samelson, Lawrence E

    2016-01-01

    Signalling complexes are dynamic, multimolecular structures and sites for intracellular signal transduction. Although they play a crucial role in cellular activation, current research techniques fail to resolve their structure in intact cells. Here we present a multicolour, photoactivated localization microscopy approach for imaging multiple types of single molecules in fixed and live cells and statistical tools to determine the nanoscale organization, topology and synergy of molecular interactions in signalling complexes downstream of the T-cell antigen receptor. We observe that signalling complexes nucleated at the key adapter LAT show a hierarchical topology. The critical enzymes PLCγ1 and VAV1 localize to the centre of LAT-based complexes, and the adapter SLP-76 and actin molecules localize to the periphery. Conditional second-order statistics reveal a hierarchical network of synergic interactions between these molecules. Our results extend our understanding of the nanostructure of signalling complexes and are relevant to studying a wide range of multimolecular complexes. PMID:27396911

  1. Star Formation Studies with SOFIA and its Synergy with TMT

    NASA Astrophysics Data System (ADS)

    De Buizer, James

    2014-07-01

    The Stratospheric Observatory For Infrared Astronomy (SOFIA) is a modified Boeing 747 aircraft equipped with a 2.5m telescope that performs observations at high altitude from the optical to the sub-mm. The observatory just reached full operational capability in April of this year. Given that it is slated for a 20-year mission lifetime, SOFIA will overlap TMT by more than a decade. I will discuss the contrasting and complementary features of SOFIA and TMT in the context of star formation, discuss some of the early results from SOFIA in this field, and finish with a discussion of how TMT data can enhance and extended our understanding of star formation processes.[This talk could also be generalized to discuss more about synergies between SOFIA and TMT in a broader context (not just star formation), should the organizers prefer that.

  2. Hierarchical nanostructure and synergy of multimolecular signalling complexes

    NASA Astrophysics Data System (ADS)

    Sherman, Eilon; Barr, Valarie A.; Merrill, Robert K.; Regan, Carole K.; Sommers, Connie L.; Samelson, Lawrence E.

    2016-07-01

    Signalling complexes are dynamic, multimolecular structures and sites for intracellular signal transduction. Although they play a crucial role in cellular activation, current research techniques fail to resolve their structure in intact cells. Here we present a multicolour, photoactivated localization microscopy approach for imaging multiple types of single molecules in fixed and live cells and statistical tools to determine the nanoscale organization, topology and synergy of molecular interactions in signalling complexes downstream of the T-cell antigen receptor. We observe that signalling complexes nucleated at the key adapter LAT show a hierarchical topology. The critical enzymes PLCγ1 and VAV1 localize to the centre of LAT-based complexes, and the adapter SLP-76 and actin molecules localize to the periphery. Conditional second-order statistics reveal a hierarchical network of synergic interactions between these molecules. Our results extend our understanding of the nanostructure of signalling complexes and are relevant to studying a wide range of multimolecular complexes.

  3. Emerging Synergy between Nanotechnology and Implantable Biosensors: A Review

    PubMed Central

    Vaddiraju, Santhisagar; Tomazos, Ioannis; Burgess, Diane J; Jain, Faquir C; Papadimitrakopoulos, Fotios

    2010-01-01

    The development of implantable biosensors for continuous monitoring of metabolites is an area of sustained scientific and technological interest. On the other hand, nanotechnology, a discipline which deals with the properties of materials at the nanoscale, is developing as a potent tool to enhance the performance of these biosensors. This article reviews the current state of implantable biosensors, highlighting the synergy between nanotechnology and sensor performance. Emphasis is placed on the electrochemical method of detection in light of its widespread usage and substantial nanotechnology-based improvements in various aspects of electrochemical biosensor performance. Finally, issues regarding toxicity and biocompatibility of nanomaterials, along with future prospects for the application of nanotechnology in implantable biosensors, are discussed. PMID:20042326

  4. Anomalies and synergy in the caloric effects of magnetoelectrics

    NASA Astrophysics Data System (ADS)

    Anand, Shashwat; Waghmare, Umesh V.

    2014-12-01

    We determine isothermal entropy changes (Δ S) associated with electrocaloric, magnetocaloric, and the corresponding multicaloric effects in a model type-I multiferroic system using Landau-Devonshire thermodynamic analysis. We show that (a) the magnetocaloric effect exhibits an unexpected anomaly at the ferroelectric transition occurring at a high temperature, even in the absence of magnetic ordering, and (b) the synergy between electro- and magnetocaloric effects leads to a significantly enhanced multicaloric effect (\\mid Δ {{S}MultiCE}\\mid \\gt \\mid Δ {{S}ECE}\\mid +\\mid Δ {{S}MCE}\\mid ) over a wide temperature range when the difference in temperatures of magnetic and ferroelectric ordering (\\mid Δ {{T}C}\\mid =\\mid TCE-TCM\\mid ) is small. This result originate from the coupled thermal fluctuations of magnetic and electric order parameters. While the former is useful in detecting multiferroic materials from the measurements covering higher temperature transition alone, the latter augurs well for caloric applications of multiferroics.

  5. Bactericidal synergy of lysostaphin in combination with antimicrobial peptides.

    PubMed

    Desbois, A P; Coote, P J

    2011-08-01

    Drug-resistant staphylococci constitute a serious problem that urgently requires the discovery of new therapeutic agents. There has been a resurgence in interest in using lysostaphin (a specific anti-staphylococcal enzyme) as a treatment for infections caused by these important pathogens. However, bacterial resistance to lysostaphin is a problem, but the use of a combination treatment may surmount this issue. In this present study, using viable counts from suspension incubations, lysostaphin is shown to be synergistically bactericidal in combination with various conventional antimicrobial peptides, the antimicrobial protein bovine lactoferrin, a lantibiotic (nisin), and certain lipopeptides used clinically (colistin, daptomycin and polymyxin B). Combinations that act in synergy are of clinical importance as these reduce the doses of the compounds needed for effective treatments and decrease the chances of resistance being selected. The use of lysostaphin in combination with a peptide may represent a new avenue in tackling drug-resistant staphylococci. PMID:21311938

  6. Technology integration and synergies: radar, optics, and AIS

    NASA Astrophysics Data System (ADS)

    Abellard, J. N.; Chen, Y.; Gonzalez Chevere, D.; Shahid, H.

    2015-05-01

    Various technologies were used to detect, track, and classify vessels on the Hudson River. Broadband radar was used to detect and track vessels. Visible light cameras, infrared cameras, and image processing techniques were used to detect, track, and classify vessels. Automatic Identification System (AIS) was used to track and classify vessels. The technologies, collectively referred to as the Integrated Technology System (ITS), were used in conjunction with each other to achieve synergies and to overcome individual system limitations. These limitations included a narrow field of view, false alarms, and misdetections. The suite of technologies successfully fulfilled its purpose. The radar was effective despite some errors. The cameras allowed for software development including automatic slewing and image processing. While AIS was considered the most reliable tool, it was determined not to be infallible. Future work includes integration of passive acoustics into the system and wake analysis for vessel detection.

  7. Achieving Synergy of Business System Via Anticipatory System

    NASA Astrophysics Data System (ADS)

    Potocan, Vojko; Rebernik, Miroslav

    2002-09-01

    The existence and development of business systems depend increasingly on its capability to keep the achieving synergy of their functioning development that presents a possible solution toward a harmonized and target oriented business. The integration processes between parts of a business system or between several business systems, lead to the quality improvement, e.g. synergetic effects. The paper discusses the thesis that the functioning of a business system (and its results) can be improved by the application of the business anticipatory systems rather than a short - sighted behavior. The anticipatory system significantly influences business functioning mainly by its ability to ensure a future oriented functioning, appropriate behavior in relation to the environment and such a direction of the behavior that would lead to flexibility and ergodics.

  8. GlobCurrent: Sentinel-3 Synergy in Action

    NASA Astrophysics Data System (ADS)

    Johannessen, J. A.; Chapron, B.; Collard, F.; Rio, M.-H.; Piolle, J.-F.; Quartly, G.; Shutler, J.; Escola, R.; Donlon, C.; Danielson, R.; Korosov, A.; Raj, R. P.; Kudryavtsev, V.; Roca, M.; Tournadre, J.; Larnicol, G.; Labroue, S.; Miller, P.; Nencioli, F.; Warren, M.; Hansen, M.

    2015-12-01

    The ESA Data User Element (DUE) funded GlobCurrent project (http://www.globcurrent.org) aims to: (i) advance the quantitative estimation of ocean surface currents from satellite sensor synergy; and (ii) demonstrate impact in user-led scientific, operational and commercial applications that, in turn, will improve and strengthen the uptake of satellite measurements. Today, a synergetic approach for quantitative analysis can build on high-resolution imaging radar and spectrometer data, infrared radiometer data and radar altimeter measurements. It will further integrate Sentinel-3 in combination with Sentinel-1 SAR data. From existing and past missions, it is often demonstrated that sharp gradients in the sea surface temperature (SST) field and the ocean surface chlorophyll-a distribution are spatially correlated with the sea surface roughness anomaly fields at small spatial scales, in the sub-mesocale (1-10 km) to the mesoscale (30-80 km). At the larger mesoscale range (>50 km), information derived from radar altimeters often depict the presence of coherent structures and eddies. The variability often appears largest in regions where the intense surface current regimes (>100 - 200 km) are found. These 2-dimensional structures manifested in the satellite observations represent evidence of the upper ocean (~100-200 m) dynamics. Whereas the quasi geostrophic assumption is valid for the upper ocean dynamics at the larger scale (>100 km), possible triggering mechanisms for the expressions at the mesoscale-to-sub-mesoscale may include spiraling tracers of inertial motion and the interaction of the wind-driven Ekman layer with the quasi-geostrophic current field. This latter, in turn, produces bands of downwelling (convergence) and upwelling (divergence) near fronts. A regular utilization of the sensor synergy approach with the combination of Sentinel-3 and Sentinel-1 will provide a highly valuable data set for further research and development to better relate the 2

  9. Synergies and trade-offs in achieving global biodiversity targets.

    PubMed

    Di Marco, Moreno; Butchart, Stuart H M; Visconti, Piero; Buchanan, Graeme M; Ficetola, Gentile F; Rondinini, Carlo

    2016-02-01

    After their failure to achieve a significant reduction in the global rate of biodiversity loss by 2010, world governments adopted 20 new ambitious Aichi biodiversity targets to be met by 2020. Efforts to achieve one particular target can contribute to achieving others, but different targets may sometimes require conflicting solutions. Consequently, lack of strategic thinking might result, once again, in a failure to achieve global commitments to biodiversity conservation. We illustrate this dilemma by focusing on Aichi Target 11. This target requires an expansion of terrestrial protected area coverage, which could also contribute to reducing the loss of natural habitats (Target 5), reducing human-induced species decline and extinction (Target 12), and maintaining global carbon stocks (Target 15). We considered the potential impact of expanding protected areas to mitigate global deforestation and the consequences for the distribution of suitable habitat for >10,000 species of forest vertebrates (amphibians, birds, and mammals). We first identified places where deforestation might have the highest impact on remaining forests and then identified places where deforestation might have the highest impact on forest vertebrates (considering aggregate suitable habitat for species). Expanding protected areas toward locations with the highest deforestation rates (Target 5) or the highest potential loss of aggregate species' suitable habitat (Target 12) resulted in partially different protected area network configurations (overlapping with each other by about 73%). Moreover, the latter approach contributed to safeguarding about 30% more global carbon stocks than the former. Further investigation of synergies and trade-offs between targets would shed light on these and other complex interactions, such as the interaction between reducing overexploitation of natural resources (Targets 6, 7), controlling invasive alien species (Target 9), and preventing extinctions of native

  10. Marine parameters from synergy of optical and radar satellite data

    NASA Astrophysics Data System (ADS)

    Lehner, S.; Hoja, D.; Schulz-Stellenfleth, J.

    In 2001 the European Space Agency ESA will launch the earth observation satellite ENVISAT. It will carry several instruments that provide new opportunities to measure oceanographic variables. Together, they represent the main measurement techniques of satellite oceanography, and complement each other in an ideal manner. These instruments are to be used in synergy to: Improve the analysis of measured wind and ocean wave fields, and thereby improve weather forecasting at weather centers; Determine the extent and variables of sea ice and develop a five-day sea ice prediction model, to support maritime shipping and offshore activities; Monitor and map sediment and suspended matter transport in coastal regions, especially in areas with large river estuaries, which greatly affects shipping lanes, harbors, and dredging activities; Monitor hydrobiological and bio-geochemical variables related to water quality in coastal regions and large inland waters, which affects ecology, coastal development, aquaculture, drinking water supplies, and tourism. To prepare the oceanographic community to make best use of the ENVISAT sensors in the pre-launch phase, existing algorithms to derive marine parameters are used and validated using data from the ERS SAR, the ERS RA, SeaWiFS and IRS MOS sensors now in operation. Derived products are used to address problems that can best be tackled using the synergy of radar and optical data, such as the effect of surface slicks on radar wind measurements, of sea state on ocean color, of wind and waves on the resuspension of suspended matter, and of wind and waves on sea ice variables.

  11. Robustness of muscle synergies underlying three-dimensional force generation at the hand in healthy humans

    PubMed Central

    Rymer, William Z.; Beer, Randall F.

    2012-01-01

    Previous studies using advanced matrix factorization techniques have shown that the coordination of human voluntary limb movements may be accomplished using combinations of a small number of intermuscular coordination patterns, or muscle synergies. However, the potential use of muscle synergies for isometric force generation has been evaluated mostly using correlational methods. The results of such studies suggest that fixed relationships between the activations of pairs of muscles are relatively rare. There is also emerging evidence that the nervous system uses independent strategies to control movement and force generation, which suggests that one cannot conclude a priori that isometric force generation is accomplished by combining muscle synergies, as shown in movement control. In this study, we used non-negative matrix factorization to evaluate the ability of a few muscle synergies to reconstruct the activation patterns of human arm muscles underlying the generation of three-dimensional (3-D) isometric forces at the hand. Surface electromyographic (EMG) data were recorded from eight key elbow and shoulder muscles during 3-D force target-matching protocols performed across a range of load levels and hand positions. Four synergies were sufficient to explain, on average, 95% of the variance in EMG datasets. Furthermore, we found that muscle synergy composition was conserved across biomechanical task conditions, experimental protocols, and subjects. Our findings are consistent with the view that the nervous system can generate isometric forces by assembling a combination of a small number of muscle synergies, differentially weighted according to task constraints. PMID:22279190

  12. The flexible recruitment of muscle synergies depends on the required force-generating capability.

    PubMed

    Hagio, Shota; Kouzaki, Motoki

    2014-07-15

    To simplify redundant motor control, the central nervous system (CNS) may modularly organize and recruit groups of muscles as "muscle synergies." However, smooth and efficient movements are expected to require not only low-dimensional organization, but also flexibility in the recruitment or combination of synergies, depending on force-generating capability of individual muscles. In this study, we examined how the CNS controls activations of muscle synergies as changing joint angles. Subjects performed multidirectional isometric force generations around right ankle and extracted the muscle synergies using nonnegative matrix factorization across various knee and hip joint angles. As a result, muscle synergies were selectively recruited with merging or decomposition as changing the joint angles. Moreover, the activation profiles, including activation levels and the direction indicating the peak, of muscle synergies across force directions depended on the joint angles. Therefore, we suggested that the CNS selects appropriate muscle synergies and controls their activation patterns based on the force-generating capability of muscles with merging or decomposing descending neural inputs. PMID:24790166

  13. Effects of 5 Weeks of Bench Press Training on Muscle Synergies: A Randomized Controlled Study.

    PubMed

    Kristiansen, Mathias; Samani, Afshin; Madeleine, Pascal; Hansen, Ernst A

    2016-07-01

    Kristiansen, M, Samani, A, Madeleine, P, and Hansen, EA. Effects of 5 weeks of bench press training on muscle synergies: A randomized controlled study. J Strength Cond Res 30(7): 1948-1959, 2016-The ability to perform forceful muscle contractions has important implications in sports performance and in activities of daily living. However, there is a lack of knowledge on adaptations in intermuscular coordination after strength training. The purpose of this study was therefore to assess muscle synergies before and after 5 weeks of bench press training. Thirty untrained male subjects were randomly allocated to a training group (TRA) or a control group (CON). After the pretest, TRA completed 5 weeks of bench press training, before completing a posttest, whereas subjects in CON continued their normal life. During test sessions, surface electromyography (EMG) was recorded from 13 different muscles. Muscle synergies were extracted from EMG data using nonnegative matrix factorization. To evaluate differences between pretest and posttest, we performed a cross-correlation analysis and a cross-validation analysis, in which the synergy components extracted in the pretest session were recomputed, using the fixed synergy components from the posttest session. Two muscle synergies accounted for 90% of the total variance and reflected the concentric and eccentric phase, respectively. TRA significantly increased 3 repetition maximum in bench press with 19.0% (25th; 75th percentile, 10.3%; 21.7%) (p < 0.001), whereas no change occurred in CON. No significant differences were observed in synergy components between groups. However, decreases in correlation values for intragroup comparisons in TRA may suggest that the synergy components changed, whereas this was not the case in CON. Strength and conditioning professionals may consider monitoring changes in muscle synergies in training and rehabilitation programs as a way to benchmark changes in intermuscular coordination. PMID:26645673

  14. Flare Hybrids

    NASA Astrophysics Data System (ADS)

    Tomczak, M.; Dubieniecki, P.

    2015-12-01

    On the basis of the Solar Maximum Mission observations, Švestka ( Solar Phys. 121, 399, 1989) introduced a new class of flares, the so-called flare hybrids. When they start, they look like typical compact flares (phase 1), but later on, they look like flares with arcades of magnetic loops (phase 2). We summarize the characteristic features of flare hybrids in soft and hard X-rays as well as in the extreme ultraviolet; these features allow us to distinguish flare hybrids from other flares. In this article, additional energy release or long plasma cooling timescales are suggested as possible causes of phase 2. We estimate the frequency of flare hybrids, and study the magnetic configurations favorable for flare hybrid occurrence. Flare hybrids appear to be quite frequent, and the difference between the lengths of magnetic loops in the two interacting loop systems seem to be a crucial parameter for determining their characteristics.

  15. Are Movement Disorders and Sensorimotor Injuries Pathologic Synergies? When Normal Multi-Joint Movement Synergies Become Pathologic

    PubMed Central

    Santello, Marco; Lang, Catherine E.

    2015-01-01

    The intact nervous system has an exquisite ability to modulate the activity of multiple muscles acting at one or more joints to produce an enormous range of actions. Seemingly simple tasks, such as reaching for an object or walking, in fact rely on very complex spatial and temporal patterns of muscle activations. Neurological disorders such as stroke and focal dystonia affect the ability to coordinate multi-joint movements. This article reviews the state of the art of research of muscle synergies in the intact and damaged nervous system, their implications for recovery and rehabilitation, and proposes avenues for research aimed at restoring the nervous system’s ability to control movement. PMID:25610391

  16. Beyond synergies. Comment on "Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands" by Marco Santello et al.

    NASA Astrophysics Data System (ADS)

    Schwartz, Andrew B.

    2016-07-01

    The target paper by Santello et al. [1] uses the observation that hand shape during grasping can be described by a small set of basic postures, or "synergies," to describe the possible neural basis of motor control during this complex behavior. In the literature, the term "synergy" has been used with a number of different meanings and is still loosely defined, making it difficult to derive concrete analogs of corresponding neural structure. Here, I will define "synergy" broadly, as a set of parameters bound together by a pattern of correlation. With this definition, it can be argued that behavioral synergies are just one facet of the correlational structuring used by the brain to generate behavior. As pointed out in the target article, the structure found in synergies is driven by the physical constraints of our bodies and our surroundings, combined with the behavioral control imparted by our nervous system. This control itself is based on correlational structure which is likely to be a fundamental property of brain function.

  17. Investigating Conversational Dynamics: Interactive Alignment, Interpersonal Synergy, and Collective Task Performance

    ERIC Educational Resources Information Center

    Fusaroli, Riccardo; Tylén, Kristian

    2016-01-01

    This study investigates interpersonal processes underlying dialog by comparing two approaches, "interactive alignment" and "interpersonal synergy", and assesses how they predict collective performance in a joint task. While the interactive alignment approach highlights imitative patterns between interlocutors, the synergy…

  18. Simulating Serial-Target Antibacterial Drug Synergies Using Flux Balance Analysis

    PubMed Central

    Dantas, Gautam; Church, George M.; Galagan, James; Lehár, Joseph; Sommer, Morten O. A.

    2016-01-01

    Flux balance analysis (FBA) is an increasingly useful approach for modeling the behavior of metabolic systems. However, standard FBA modeling of genetic knockouts cannot predict drug combination synergies observed between serial metabolic targets, even though such synergies give rise to some of the most widely used antibiotic treatments. Here we extend FBA modeling to simulate responses to chemical inhibitors at varying concentrations, by diverting enzymatic flux to a waste reaction. This flux diversion yields very similar qualitative predictions to prior methods for single target activity. However, we find very different predictions for combinations, where flux diversion, which mimics the kinetics of competitive metabolic inhibitors, can explain serial target synergies between metabolic enzyme inhibitors that we confirmed in Escherichia coli cultures. FBA flux diversion opens the possibility for more accurate genome-scale predictions of drug synergies, which can be used to suggest treatments for infections and other diseases. PMID:26821252

  19. Exploring the molecular basis of antifungal synergies using genome-wide approaches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is a review article summarizing genomic profiling strategies for determining the mechanism of action of antifungal synergies, and highlighting the potential applications of these technologies. Given the limitations of currently available antifungal agents and the development of drug resistance...

  20. Muscle synergies for reliable classification of arm motions using myoelectric interface.

    PubMed

    Antuvan, Chris Wilson; Bisio, Federica; Cambria, Erik; Masia, Lorenzo

    2015-08-01

    Synergistic activation of muscles are considered to be the phenomenon by which the central nervous system simplifies its control strategy. Muscle synergies are neurally encoded and considered robust to be able to adapt for various external dynamics. This paper presents a myoelectric-based interface to identify and classify motions of the upper arm involving the shoulder and elbow. We contrast performance of the decoder while using time domain and synergy features. The decoder is trained using extreme learning machine algorithm, and online testing is performed in a virtual environment. Better classification accuracy for online control is obtained while using muscle synergy features. The results indicate better online performance compared to offline performance while using synergy features to classify movements, indicating generalization to dynamic situations and robustness of control. PMID:26736466

  1. Motor primitives and synergies in spinal cord and after injury– the current state of play

    PubMed Central

    Giszter, Simon F.; Hart, Corey B.

    2013-01-01

    Modular pattern generator elements, also known as burst synergies or motor primitives, have become a useful and important way of describing motor behavior, albeit controversial. It is suggested that these synergy elements may comprise part of the pattern shaping layers of a McCrea/Rybak two layer pattern generator, as well as being used in other ways in spinal cord. The data supporting modular synergies ranges across species including man and encompasses motor pattern analyses and neural recordings. Recently, synergy persistence and changes following clinical trauma have been presented. These new data underscore the importance of understanding the modular structure of motor behaviors and the underlying circuitry in order to best provide principled therapies and to understand phenomena reported in the clinic. We discuss the evidence and different viewpoints on modularity, the neural underpinnings identified thus far, and possible critical issues for the future of this area. PMID:23531009

  2. Synergy Between Astrochemical Models and Cometary Taxonomies of Parent Volatiles

    NASA Astrophysics Data System (ADS)

    Bonev, Boncho P.; Willacy, Karen; Mumma, Michael J.; Gibb, Erika L.; Millar, Tom; Charnley, Steve; DiSanti, Michael A.; Villanueva, Geronimo L.; Paganini, Lucas

    2014-11-01

    The principal output in taxonomic studies of cometary primary (parent) volatiles is the suite of “mixing ratios” between observed species. These ratios relate the abundances of different molecules (CH4/C2H2/C2H6/H2CO/CH3OH/H2O, etc.) or isotopologues (HDO/H2O, CH3D/CH4, etc.). Infrared and radio observations have found strong evidence that mixing ratios vary substantially among comets. However, we still face serious uncertainties in decoding the cosmogonic significance of the measured abundances. The observed composition of comets may be an end product of a variety of processes, including chemical evolution in the protoplanetary disk, dynamical evolution in the young solar system, and (perhaps) thermal evolution during successive perihelion passages. Improved understanding of their relative importance requires additional sensitive measurements and a comprehensive synergy with astrochemical models. These models find that protoplanetary disks can be divided into three distinct regions: (1) a cold midplane, where ices freeze to dust grains; (2) a warm molecular layer, where ices sublimate and are processed via gas-phase reactions; and (3) a hot disk atmosphere containing predominantly atoms and atomic ions. Material from the different layers can be mixed by transport processes.We will show how this synergy is being realized via close collaboration between modeling and observing teams. The goal is a deeper insight into the processes preceding comet formation that may have influenced the composition - what chemical reaction pathways dominated the synthesis of cometary compounds? What processes in the protoplanetary disk have left strong signatures in cometary ices? Can models provide testable predictions for the chemical diversity observed among comets? Addressing these questions, we will show initial comparisons between relative abundances for several cometary volatiles and those predicted for the midplane of the protoplanetary disk where comets formed. We will

  3. Forest Biomass Mapping From Lidar and Radar Synergies

    NASA Technical Reports Server (NTRS)

    Sun, Guoqing; Ranson, K. Jon; Guo, Z.; Zhang, Z.; Montesano, P.; Kimes, D.

    2011-01-01

    The use of lidar and radar instruments to measure forest structure attributes such as height and biomass at global scales is being considered for a future Earth Observation satellite mission, DESDynI (Deformation, Ecosystem Structure, and Dynamics of Ice). Large footprint lidar makes a direct measurement of the heights of scatterers in the illuminated footprint and can yield accurate information about the vertical profile of the canopy within lidar footprint samples. Synthetic Aperture Radar (SAR) is known to sense the canopy volume, especially at longer wavelengths and provides image data. Methods for biomass mapping by a combination of lidar sampling and radar mapping need to be developed. In this study, several issues in this respect were investigated using aircraft borne lidar and SAR data in Howland, Maine, USA. The stepwise regression selected the height indices rh50 and rh75 of the Laser Vegetation Imaging Sensor (LVIS) data for predicting field measured biomass with a R(exp 2) of 0.71 and RMSE of 31.33 Mg/ha. The above-ground biomass map generated from this regression model was considered to represent the true biomass of the area and used as a reference map since no better biomass map exists for the area. Random samples were taken from the biomass map and the correlation between the sampled biomass and co-located SAR signature was studied. The best models were used to extend the biomass from lidar samples into all forested areas in the study area, which mimics a procedure that could be used for the future DESDYnI Mission. It was found that depending on the data types used (quad-pol or dual-pol) the SAR data can predict the lidar biomass samples with R2 of 0.63-0.71, RMSE of 32.0-28.2 Mg/ha up to biomass levels of 200-250 Mg/ha. The mean biomass of the study area calculated from the biomass maps generated by lidar- SAR synergy 63 was within 10% of the reference biomass map derived from LVIS data. The results from this study are preliminary, but do show the

  4. Transdisciplinary breastfeeding support: Creating program and policy synergy across the reproductive continuum

    PubMed Central

    Labbok, Miriam H

    2008-01-01

    This paper was presented at the symposium on Breastfeeding and Feminism: A Focus on Reproductive Health, Rights and Justice. It underscores the power and potential of synergy between and among organizations and individuals supporting breastfeeding, the mother-child dyad, and reproductive health to increase sustainable breastfeeding support. These concepts were brought together to lay the groundwork for working group discussions of synergy in program and policy actions. PMID:18680583

  5. Quantifying Synergy: A Systematic Review of Mixture Toxicity Studies within Environmental Toxicology

    PubMed Central

    Cedergreen, Nina

    2014-01-01

    Cocktail effects and synergistic interactions of chemicals in mixtures are an area of great concern to both the public and regulatory authorities. The main concern is whether some chemicals can enhance the effect of other chemicals, so that they jointly exert a larger effect than predicted. This phenomenon is called synergy. Here we present a review of the scientific literature on three main groups of environmentally relevant chemical toxicants: pesticides, metal ions and antifouling compounds. The aim of the review is to determine 1) the frequency of synergy, 2) the extent of synergy, 3) whether any particular groups or classes of chemicals tend to induce synergy, and 4) which physiological mechanisms might be responsible for this synergy. Synergy is here defined as mixtures with minimum two-fold difference between observed and predicted effect concentrations using Concentration Addition (CA) as a reference model and including both lethal and sub-lethal endpoints. The results showed that synergy occurred in 7%, 3% and 26% of the 194, 21 and 136 binary pesticide, metal and antifoulants mixtures included in the data compilation on frequency. The difference between observed and predicted effect concentrations was rarely more than 10-fold. For pesticides, synergistic mixtures included cholinesterase inhibitors or azole fungicides in 95% of 69 described cases. Both groups of pesticides are known to interfere with metabolic degradation of other xenobiotics. For the four synergistic metal and 47 synergistic antifoulant mixtures the pattern in terms of chemical groups inducing synergy was less clear. Hypotheses in terms of mechanisms governing these interactions are discussed. It was concluded that true synergistic interactions between chemicals are rare and often occur at high concentrations. Addressing the cumulative rather than synergistic effect of co-occurring chemicals, using standard models as CA, is therefore regarded as the most important step in the risk

  6. Muscle synergies in neuroscience and robotics: from input-space to task-space perspectives

    PubMed Central

    Alessandro, Cristiano; Delis, Ioannis; Nori, Francesco; Panzeri, Stefano; Berret, Bastien

    2013-01-01

    In this paper we review the works related to muscle synergies that have been carried-out in neuroscience and control engineering. In particular, we refer to the hypothesis that the central nervous system (CNS) generates desired muscle contractions by combining a small number of predefined modules, called muscle synergies. We provide an overview of the methods that have been employed to test the validity of this scheme, and we show how the concept of muscle synergy has been generalized for the control of artificial agents. The comparison between these two lines of research, in particular their different goals and approaches, is instrumental to explain the computational implications of the hypothesized modular organization. Moreover, it clarifies the importance of assessing the functional role of muscle synergies: although these basic modules are defined at the level of muscle activations (input-space), they should result in the effective accomplishment of the desired task. This requirement is not always explicitly considered in experimental neuroscience, as muscle synergies are often estimated solely by analyzing recorded muscle activities. We suggest that synergy extraction methods should explicitly take into account task execution variables, thus moving from a perspective purely based on input-space to one grounded on task-space as well. PMID:23626535

  7. Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands

    NASA Astrophysics Data System (ADS)

    Santello, Marco; Bianchi, Matteo; Gabiccini, Marco; Ricciardi, Emiliano; Salvietti, Gionata; Prattichizzo, Domenico; Ernst, Marc; Moscatelli, Alessandro; Jörntell, Henrik; Kappers, Astrid M. L.; Kyriakopoulos, Kostas; Albu-Schäffer, Alin; Castellini, Claudio; Bicchi, Antonio

    2016-07-01

    The term 'synergy' - from the Greek synergia - means 'working together'. The concept of multiple elements working together towards a common goal has been extensively used in neuroscience to develop theoretical frameworks, experimental approaches, and analytical techniques to understand neural control of movement, and for applications for neuro-rehabilitation. In the past decade, roboticists have successfully applied the framework of synergies to create novel design and control concepts for artificial hands, i.e., robotic hands and prostheses. At the same time, robotic research on the sensorimotor integration underlying the control and sensing of artificial hands has inspired new research approaches in neuroscience, and has provided useful instruments for novel experiments. The ambitious goal of integrating expertise and research approaches in robotics and neuroscience to study the properties and applications of the concept of synergies is generating a number of multidisciplinary cooperative projects, among which the recently finished 4-year European project "The Hand Embodied" (THE). This paper reviews the main insights provided by this framework. Specifically, we provide an overview of neuroscientific bases of hand synergies and introduce how robotics has leveraged the insights from neuroscience for innovative design in hardware and controllers for biomedical engineering applications, including myoelectric hand prostheses, devices for haptics research, and wearable sensing of human hand kinematics. The review also emphasizes how this multidisciplinary collaboration has generated new ways to conceptualize a synergy-based approach for robotics, and provides guidelines and principles for analyzing human behavior and synthesizing artificial robotic systems based on a theory of synergies.

  8. Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands.

    PubMed

    Santello, Marco; Bianchi, Matteo; Gabiccini, Marco; Ricciardi, Emiliano; Salvietti, Gionata; Prattichizzo, Domenico; Ernst, Marc; Moscatelli, Alessandro; Jörntell, Henrik; Kappers, Astrid M L; Kyriakopoulos, Kostas; Albu-Schäffer, Alin; Castellini, Claudio; Bicchi, Antonio

    2016-07-01

    The term 'synergy' - from the Greek synergia - means 'working together'. The concept of multiple elements working together towards a common goal has been extensively used in neuroscience to develop theoretical frameworks, experimental approaches, and analytical techniques to understand neural control of movement, and for applications for neuro-rehabilitation. In the past decade, roboticists have successfully applied the framework of synergies to create novel design and control concepts for artificial hands, i.e., robotic hands and prostheses. At the same time, robotic research on the sensorimotor integration underlying the control and sensing of artificial hands has inspired new research approaches in neuroscience, and has provided useful instruments for novel experiments. The ambitious goal of integrating expertise and research approaches in robotics and neuroscience to study the properties and applications of the concept of synergies is generating a number of multidisciplinary cooperative projects, among which the recently finished 4-year European project "The Hand Embodied" (THE). This paper reviews the main insights provided by this framework. Specifically, we provide an overview of neuroscientific bases of hand synergies and introduce how robotics has leveraged the insights from neuroscience for innovative design in hardware and controllers for biomedical engineering applications, including myoelectric hand prostheses, devices for haptics research, and wearable sensing of human hand kinematics. The review also emphasizes how this multidisciplinary collaboration has generated new ways to conceptualize a synergy-based approach for robotics, and provides guidelines and principles for analyzing human behavior and synthesizing artificial robotic systems based on a theory of synergies. PMID:26923030

  9. Stability of muscle synergies for voluntary actions after cortical stroke in humans

    PubMed Central

    Cheung, Vincent C. K.; Piron, Lamberto; Agostini, Michela; Silvoni, Stefano; Turolla, Andrea; Bizzi, Emilio

    2009-01-01

    Production of voluntary movements relies critically on the functional integration of several motor cortical areas, such as the primary motor cortex, and the spinal circuitries. Surprisingly, after almost 40 years of research, how the motor cortices specify descending neural signals destined for the downstream interneurons and motoneurons has remained elusive. In light of the many recent experimental demonstrations that the motor system may coordinate muscle activations through a linear combination of muscle synergies, we hypothesize that the motor cortices may function to select and activate fixed muscle synergies specified by the spinal or brainstem networks. To test this hypothesis, we recorded electromyograms (EMGs) from 12–16 upper arm and shoulder muscles from both the unaffected and the stroke-affected arms of stroke patients having moderate-to-severe unilateral ischemic lesions in the frontal motor cortical areas. Analyses of EMGs using a nonnegative matrix factorization algorithm revealed that in seven of eight patients the muscular compositions of the synergies for both the unaffected and the affected arms were strikingly similar to each other despite differences in motor performance between the arms, and differences in cerebral lesion sizes and locations between patients. This robustness of muscle synergies that we observed supports the notion that descending cortical signals represent neuronal drives that select, activate, and flexibly combine muscle synergies specified by networks in the spinal cord and/or brainstem. Our conclusion also suggests an approach to stroke rehabilitation by focusing on those synergies with altered activations after stroke. PMID:19880747

  10. Muscle synergies in neuroscience and robotics: from input-space to task-space perspectives.

    PubMed

    Alessandro, Cristiano; Delis, Ioannis; Nori, Francesco; Panzeri, Stefano; Berret, Bastien

    2013-01-01

    In this paper we review the works related to muscle synergies that have been carried-out in neuroscience and control engineering. In particular, we refer to the hypothesis that the central nervous system (CNS) generates desired muscle contractions by combining a small number of predefined modules, called muscle synergies. We provide an overview of the methods that have been employed to test the validity of this scheme, and we show how the concept of muscle synergy has been generalized for the control of artificial agents. The comparison between these two lines of research, in particular their different goals and approaches, is instrumental to explain the computational implications of the hypothesized modular organization. Moreover, it clarifies the importance of assessing the functional role of muscle synergies: although these basic modules are defined at the level of muscle activations (input-space), they should result in the effective accomplishment of the desired task. This requirement is not always explicitly considered in experimental neuroscience, as muscle synergies are often estimated solely by analyzing recorded muscle activities. We suggest that synergy extraction methods should explicitly take into account task execution variables, thus moving from a perspective purely based on input-space to one grounded on task-space as well. PMID:23626535

  11. A methodology for assessing the effect of correlations among muscle synergy activations on task-discriminating information

    PubMed Central

    Delis, Ioannis; Berret, Bastien; Pozzo, Thierry; Panzeri, Stefano

    2013-01-01

    Muscle synergies have been hypothesized to be the building blocks used by the central nervous system to generate movement. According to this hypothesis, the accomplishment of various motor tasks relies on the ability of the motor system to recruit a small set of synergies on a single-trial basis and combine them in a task-dependent manner. It is conceivable that this requires a fine tuning of the trial-to-trial relationships between the synergy activations. Here we develop an analytical methodology to address the nature and functional role of trial-to-trial correlations between synergy activations, which is designed to help to better understand how these correlations may contribute to generating appropriate motor behavior. The algorithm we propose first divides correlations between muscle synergies into types (noise correlations, quantifying the trial-to-trial covariations of synergy activations at fixed task, and signal correlations, quantifying the similarity of task tuning of the trial-averaged activation coefficients of different synergies), and then uses single-trial methods (task-decoding and information theory) to quantify their overall effect on the task-discriminating information carried by muscle synergy activations. We apply the method to both synchronous and time-varying synergies and exemplify it on electromyographic data recorded during performance of reaching movements in different directions. Our method reveals the robust presence of information-enhancing patterns of signal and noise correlations among pairs of synchronous synergies, and shows that they enhance by 9–15% (depending on the set of tasks) the task-discriminating information provided by the synergy decompositions. We suggest that the proposed methodology could be useful for assessing whether single-trial activations of one synergy depend on activations of other synergies and quantifying the effect of such dependences on the task-to-task differences in muscle activation patterns. PMID

  12. Locus equations are an acoustic expression of articulator synergy

    PubMed Central

    Iskarous, Khalil; Fowler, Carol A.; Whalen, D. H.

    2010-01-01

    The study investigated the articulatory basis of locus equations, regression lines relating F2 at the start of a Consonant-Vowel (CV) transition to F2 at the middle of the vowel, with C fixed and V varying. Several studies have shown that consonants of different places of articulation have locus equation slopes that descend from labial to velar to alveolar, and intercept magnitudes that increase in the opposite order. Using formulas from the theory of bivariate regression that express regression slopes and intercepts in terms of standard deviations and averages of the variables, it is shown that the slope directly encodes a well-established measure of coarticulation resistance. It is also shown that intercepts are directly related to the degree to which the tongue body assists the formation of the constriction for the consonant. Moreover, it is shown that the linearity of locus equations and the linear relation between locus equation slopes and intercepts originates in linearity in articulation between the horizontal position of the tongue dorsum in the consonant and to that in the vowel. It is concluded that slopes and intercepts of acoustic locus equations are measures of articulator synergy. PMID:20968373

  13. Global phosphorus scarcity: identifying synergies for a sustainable future.

    PubMed

    Neset, Tina-Simone S; Cordell, Dana

    2012-01-15

    Global food production is dependent on constant inputs of phosphorus. In the current system this phosphorus is not predominantly derived from organic recycled waste, but to a large degree from phosphate-rock based mineral fertilisers. However, phosphate rock is a finite resource that cannot be manufactured. Our dependency therefore needs to be addressed from a sustainability perspective in order to ensure global food supplies for a growing global population. The situation is made more urgent by predictions that, for example, the consumption of resource intensive foods and the demand for biomass energy will increase. The scientific and societal debate has so far been focussed on the exact timing of peak phosphorus and on when the total depletion of the global reserves will occur. Even though the timing of these events is important, all dimensions of phosphorus scarcity need to be addressed in a manner which acknowledges linkages to other sustainable development challenges and which takes into consideration the synergies between different sustainability measures. Many sustainable phosphorus measures have positive impacts on other challenges; for example, shifting global diets to more plant-based foods would not only reduce global phosphorus consumption, but also reduce greenhouse gas emissions, reduce nitrogen fertiliser demand and reduce water consumption. PMID:21969145

  14. 10+ more years of Chandra-XMM-Newton Synergy

    NASA Astrophysics Data System (ADS)

    Wilkes, B.

    2016-06-01

    In this current golden age of X-ray astronomy, the frontiers of the X-ray Universe are continually expanding in multiple, often unexpected, directions, due to the extraordinary success and longevity of both ESA's XMM-Newton and NASA's Chandra X-ray Observatory. These two ground-breaking, major observatories are supported by a number of smaller, more focused missions which feed into and expand the discovery space of X-ray astronomy even further. With the prospect of another decade of observing, now is an excellent time to take stock of how far we have come, and to look forward to the future with a view to maximizing the scientific legacy of both XMM-Newton and Chandra. This not only involves optimizing the contents of the archives and the impact of the science results, but also laying the ground-work for the next generation of X-ray telescopes, led by ESA's Athena mission in the late 2020s. I will summarize the synergy between XMM-Newton and Chandra, including complementary capabilities which facilitate coordinated observations and science programs, and overlapping capabilities which often provide the necessary confirmation (or not) of new, marginal and/or controversial results.

  15. Synergy between intention recognition and commitments in cooperation dilemmas

    NASA Astrophysics Data System (ADS)

    Han, The Anh; Santos, Francisco C.; Lenaerts, Tom; Pereira, Luís Moniz

    2015-03-01

    Commitments have been shown to promote cooperation if, on the one hand, they can be sufficiently enforced, and on the other hand, the cost of arranging them is justified with respect to the benefits of cooperation. When either of these constraints is not met it leads to the prevalence of commitment free-riders, such as those who commit only when someone else pays to arrange the commitments. Here, we show how intention recognition may circumvent such weakness of costly commitments. We describe an evolutionary model, in the context of the one-shot Prisoner's Dilemma, showing that if players first predict the intentions of their co-player and propose a commitment only when they are not confident enough about their prediction, the chances of reaching mutual cooperation are largely enhanced. We find that an advantageous synergy between intention recognition and costly commitments depends strongly on the confidence and accuracy of intention recognition. In general, we observe an intermediate level of confidence threshold leading to the highest evolutionary advantage, showing that neither unconditional use of commitment nor intention recognition can perform optimally. Rather, our results show that arranging commitments is not always desirable, but that they may be also unavoidable depending on the strength of the dilemma.

  16. Air quality and climate--synergies and trade-offs.

    PubMed

    von Schneidemesser, Erika; Monks, Paul S

    2013-07-01

    Air quality and climate are often treated as separate science and policy areas. Air quality encompasses the here-and-now of pollutant emissions, atmospheric transformations and their direct effect on human and ecosystem health. Climate change deals with the drivers leading to a warmer world and the consequences of that. These two science and policy issues are inexorably linked via common pollutants, such as ozone (methane) and black carbon. This short review looks at the new scientific evidence around so-called "short-lived climate forcers" and the growing realisation that a way to meet short-term climate change targets may be through the control of "air quality" pollutants. None of the options discussed here can replace reduction of long-lived greenhouse gases, such as CO2, which is required for any long-term climate change mitigation strategy. An overview is given of the underlying science, remaining uncertainties, and some of the synergies and trade-offs for addressing air quality and climate in the science and policy context. PMID:23743609

  17. Synergy between intention recognition and commitments in cooperation dilemmas

    PubMed Central

    Han, The Anh; Santos, Francisco C.; Lenaerts, Tom; Pereira, Luís Moniz

    2015-01-01

    Commitments have been shown to promote cooperation if, on the one hand, they can be sufficiently enforced, and on the other hand, the cost of arranging them is justified with respect to the benefits of cooperation. When either of these constraints is not met it leads to the prevalence of commitment free-riders, such as those who commit only when someone else pays to arrange the commitments. Here, we show how intention recognition may circumvent such weakness of costly commitments. We describe an evolutionary model, in the context of the one-shot Prisoner's Dilemma, showing that if players first predict the intentions of their co-player and propose a commitment only when they are not confident enough about their prediction, the chances of reaching mutual cooperation are largely enhanced. We find that an advantageous synergy between intention recognition and costly commitments depends strongly on the confidence and accuracy of intention recognition. In general, we observe an intermediate level of confidence threshold leading to the highest evolutionary advantage, showing that neither unconditional use of commitment nor intention recognition can perform optimally. Rather, our results show that arranging commitments is not always desirable, but that they may be also unavoidable depending on the strength of the dilemma. PMID:25791431

  18. Synergy between intention recognition and commitments in cooperation dilemmas.

    PubMed

    Han, The Anh; Santos, Francisco C; Lenaerts, Tom; Pereira, Luís Moniz

    2015-01-01

    Commitments have been shown to promote cooperation if, on the one hand, they can be sufficiently enforced, and on the other hand, the cost of arranging them is justified with respect to the benefits of cooperation. When either of these constraints is not met it leads to the prevalence of commitment free-riders, such as those who commit only when someone else pays to arrange the commitments. Here, we show how intention recognition may circumvent such weakness of costly commitments. We describe an evolutionary model, in the context of the one-shot Prisoner's Dilemma, showing that if players first predict the intentions of their co-player and propose a commitment only when they are not confident enough about their prediction, the chances of reaching mutual cooperation are largely enhanced. We find that an advantageous synergy between intention recognition and costly commitments depends strongly on the confidence and accuracy of intention recognition. In general, we observe an intermediate level of confidence threshold leading to the highest evolutionary advantage, showing that neither unconditional use of commitment nor intention recognition can perform optimally. Rather, our results show that arranging commitments is not always desirable, but that they may be also unavoidable depending on the strength of the dilemma. PMID:25791431

  19. The Einstein-Brazil Fogarty: A decade of synergy

    PubMed Central

    Nosanchuk, Joshua D.; Nosanchuk, Murphy D.; Rodrigues, Marcio L.; Nimrichter, Leonardo; de Carvalho, Antonio C. Campos; Weiss, Louis M.; Spray, David C.; Tanowitz, Herbert B.

    2015-01-01

    Abstract A rich, collaborative program funded by the US NIH Fogarty program in 2004 has provided for a decade of remarkable opportunities for scientific advancement through the training of Brazilian undergraduate, graduate and postdoctoral students from the Federal University and Oswaldo Cruz Foundation systems at Albert Einstein College of Medicine. The focus of the program has been on the development of trainees in the broad field of Infectious Diseases, with a particular focus on diseases of importance to the Brazilian population. Talented trainees from various regions in Brazil came to Einstein to learn techniques and study fungal, parasitic and bacterial pathogens. In total, 43 trainees enthusiastically participated in the program. In addition to laboratory work, these students took a variety of courses at Einstein, presented their results at local, national and international meetings, and productively published their findings. This program has led to a remarkable synergy of scientific discovery for the participants during a time of rapid acceleration of the scientific growth in Brazil. This collaboration between Brazilian and US scientists has benefitted both countries and serves as a model for future training programs between these countries. PMID:26691452

  20. James Webb Space Telescope Synergy with Dark Energy Missions

    NASA Astrophysics Data System (ADS)

    Gardner, Jonathan P.

    2014-01-01

    As the successor to the Hubble Space Telescope (HST), the James Webb Space Telescope (JWST) will be a general-purpose observatory which will impact all areas of observational astronomy. Two future dark energy missions are being planned: Euclid in Europe and the Wide-Field Infrared Survey Telescope (WFIRST) in the US. While JWST is designed to go very deep in the infrared, the dark energy missions will conduct wide-area surveys of a substantial fraction of the sky in the optical and near-infrared. Synergy between JWST and Euclid or WFIRST could proceed in several ways. (1) JWST will make contributions to dark energy science that will be complementary to the results from the wide-area surveys. These contributions could include a more precise measurement of the current value of the Hubble constant, and rest-frame near-infrared light curves for high-redshift type Ia supernovae. (2) JWST could directly contribute to the dark energy science of the wide-area missions by providing additional calibration, investigating anomalies in the dataset, or with complementary observations that are deeper over a smaller area. (3) JWST could make follow-up observations of Euclid or WFIRST discoveries of rare objects, such as high-redshift quasars, strong-lens systems, galaxy clusters and supernovae.

  1. Synergy with new radio facilities: from LOFAR to SKA

    NASA Astrophysics Data System (ADS)

    Morganti, R.

    2016-06-01

    A number of new radio telescopes are coming on-line paving the way to the Square Kilometre Array. Their new capabilities, e.g. large field of view, broad instantaneous band and fast response, offer new possibilities for the science. I will briefly give an overview of the facilities that are becoming available. Many of them have open time and some are planning large surveys that will be made available to the entire astronomical community, providing an important legacy. I will then focus on some of the results obtained with the Low Frequency Array (LOFAR) on topics where a strong synergy with XMM is (or should be) present. In particular, I will focus on pulsars (e.g. fast switching mode pulsars) and accreting systems among the galactic objects. For the extragalactic objects, the combination radio/X-ray is key for understanding the energetics and, therefore, the impact that radio AGN have on their surroundings. I will in particular focus on results from observations of radio galaxies and clusters. Fast response to transient objects in the radio sky is also receiving a lot of attention with LOFAR (and other radio telescopes).

  2. Comparison of Vehicle Efficiency Technology Attributes and Synergy Estimates

    SciTech Connect

    Duleep, G.

    2011-02-01

    Analyzing the future fuel economy of light-duty vehicles (LDVs) requires detailed knowledge of the vehicle technologies available to improve LDV fuel economy. The National Highway Transportation Safety Administration (NHTSA) has been relying on technology data from a 2001 National Academy of Sciences (NAS) study (NAS 2001) on corporate average fuel economy (CAFE) standards, but the technology parameters were updated in the new proposed rulemaking (EPA and NHTSA 2009) to set CAFE and greenhouse gas standards for the 2011 to 2016 period. The update is based largely on an Environmental Protection Agency (EPA) analysis of technology attributes augmented by NHTSA data and contractor staff assessments. These technology cost and performance data were documented in the Draft Joint Technical Support Document (TSD) issued by EPA and NHTSA in September 2009 (EPA/NHTSA 2009). For these tasks, the Energy and Environmental Analysis (EEA) division of ICF International (ICF) examined each technology and technology package in the Draft TSD and assessed their costs and performance potential based on U.S. Department of Energy (DOE) program assessments. ICF also assessed the technologies, other relevant attributes based on data from actual production vehicles, and recently published technical articles in engineering journals. ICF examined technology synergy issues through an ICF in-house model that uses a discrete parameter approach.

  3. Comparison of Vehicle Efficiency Technology Attributes and Synergy Estimates

    SciTech Connect

    Duleep, G.

    2011-02-01

    Analyzing the future fuel economy of light-duty vehicles (LDVs) requires detailed knowledge of the vehicle technologies available to improve LDV fuel economy. The National Highway Transportation Safety Administration (NHTSA) has been relying on technology data from a 2001 National Academy of Sciences (NAS) study (NAS 2001) on corporate average fuel economy (CAFE) standards, but the technology parameters were updated in the new proposed rulemaking (EPA and NHTSA 2009) to set CAFE and greenhouse gas standards for the 2011 to 2016 period. The update is based largely on an Environmental Protection Agency (EPA) analysis of technology attributes augmented by NHTSA data and contractor staff assessments. These technology cost and performance data were documented in the Draft Joint Technical Support Document (TSD) issued by EPA and NHTSA in September 2009 (EPA/NHTSA 2009). For these tasks, the Energy and Environmental Analysis (EEA) division of ICF International (ICF) examined each technology and technology package in the Draft TSD and assessed their costs and performance potential based on U.S. Department of Energy (DOE) program assessments. ICF also assessed the technologies? other relevant attributes based on data from actual production vehicles and from recently published technical articles in engineering journals. ICF examined technology synergy issues through an ICF in-house model that uses a discrete parameter approach.

  4. Facilitating Inter-Domain Synergies in Ambient Assisted Living Environments.

    PubMed

    Schwartze, Jonas; Schrom, Harald; Wolf, Klaus-Hendrik; Marschollek, Michael

    2016-01-01

    Current Ambient Assisted Living (AAL) environments lack integration of sensors and actuators of other sub-domains. Creating technical and organizational integration is addressed by the BASIS project (Build Automation by a Scalable and Intelligent System), which aims to build a cross-domain home bus system. The main objective of this paper is to present an overview of design, architecture and state of realization of BASIS by describing the requirements development process, underlying hardware design and software architecture. We built a distributed system of one independent building manager with several redundantly meshed segment controllers, each controlling a bus segment with any number of bus nodes. The software system layer is divided into logical partitions representing each sub-domain. Structured data storage is possible with a special FHIR based home centered data warehouse. The system has been implemented in six apartments running under daily living conditions. BASIS integrates a broad range of sub-domains, which poses challenges to all project partners in terms of a common terminology, and project management methods, but enables development of inter-domain synergies like using the same sensor and actuator hardware for a broad range of services and use cases. PMID:27577428

  5. Ocean Surface reconstruction from the synergy of Sentinel-3 sensors

    NASA Astrophysics Data System (ADS)

    Gonzalez-Haro, C.; Autret, E.; Isern-Fontanet, J.; Tandeo, P.; Le Goff, C.; Garello, R.; Fablet, R.

    2015-12-01

    Along-track altimetric measurements of Sea Surface Heights (SSH) are very well suited to quantify across-track currents. However, the spatial resolution of derived 2D velocities is restricted to scales above 100-150 km and the limited number of altimeters can lead to errors in the location of currents. On the contrary, infrared measurements of Sea Surface Temperature (SST) are well suited to locate flow patterns but it is difficult to extract quantitative estimations of ocean currents. During the last years, some works began to exploit the synergy of SST and altimetry measurements in order to retrieve ocean currents. Nevertheless, all this previous works employed measurements which were near in time but not simultaneous. In that sense, Sentinel-3 is a multi-instrument mission that will circumvent this temporal limitation, providing simultaneous measurements of SST and altimetry with high-end accuracy and reliability. Our approach, based on the spectral properties of simultaneous SST and SSH observations, is tested using ENVISAT (RA, AATSR) data, since its geometry is similar to that of Sentinel-3 (SRAL, SLSTR).

  6. Integrating parasitology and marine ecology: Seven challenges towards greater synergy

    NASA Astrophysics Data System (ADS)

    Poulin, Robert; Blasco-Costa, Isabel; Randhawa, Haseeb S.

    2016-07-01

    Despite their very different historical origins as scientific disciplines, parasitology and marine ecology have already combined successfully to make important contributions to our understanding of the functioning of natural ecosystems. For example, robust assessments of the contribution of parasites to ecosystem biomass and energetics, and of their impact on community-wide biodiversity and food web structure, have all been made for the first time in marine systems. Nevertheless, for the marriage between parasitology and marine ecology to remain fruitful, several challenges must first be overcome. We discuss seven such challenges on the road to a greater synergy between these disciplines: (1) Raising awareness of parasitism as an ecological force by increasing the proportion of articles about parasites and diseases in marine ecology journals; (2) Making greater use of theory and conceptual frameworks from marine ecology to guide parasitological research; (3) Speeding up or at least maintaining the current rate at which marine parasites are found and described; (4) Elucidating a greater proportion of life cycles in all major groups of marine parasites; (5) Increasing the number of host-parasite model systems on which our knowledge is based; (6) Extending parasitological research offshore and into ocean depths; and (7) Developing, as needed, new epidemiological theory and transmission models for the marine environment. None of these challenges is insurmountable, and addressing just a few of them should guarantee that parasitology and marine ecology will continue to join forces and make further substantial contributions.

  7. A hybrid air conditioner driven by a hybrid solar collector

    NASA Astrophysics Data System (ADS)

    Al-Alili, Ali

    The objective of this thesis is to search for an efficient way of utilizing solar energy in air conditioning applications. The current solar Air Conditioners (A/C)s suffer from low Coefficient of Performance (COP) and performance degradation in hot and humid climates. By investigating the possible ways of utilizing solar energy in air conditioning applications, the bottlenecks in these approaches were identified. That resulted in proposing a novel system whose subsystem synergy led to a COP higher than unity. The proposed system was found to maintain indoor comfort at a higher COP compared to the most common solar A/Cs, especially under very hot and humid climate conditions. The novelty of the proposed A/C is to use a concentrating photovoltaic/thermal collector, which outputs thermal and electrical energy simultaneously, to drive a hybrid A/C. The performance of the hybrid A/C, which consists of a desiccant wheel, an enthalpy wheel, and a vapor compression cycle (VCC), was investigated experimentally. This work also explored the use of a new type of desiccant material, which can be regenerated with a low temperature heat source. The experimental results showed that the hybrid A/C is more effective than the standalone VCC in maintaining the indoor conditions within the comfort zone. Using the experimental data, the COP of the hybrid A/C driven by a hybrid solar collector was found to be at least double that of the current solar A/Cs. The innovative integration of its subsystems allows each subsystem to do what it can do best. That leads to lower energy consumption which helps reduce the peak electrical loads on electric utilities and reduces the consumer operating cost since less energy is purchased during the on peak periods and less solar collector area is needed. In order for the proposed A/C to become a real alternative to conventional systems, its performance and total cost were optimized using the experimentally validated model. The results showed that for an

  8. Stellarator hybrids

    SciTech Connect

    Furth, H.P.; Ludescher, C.

    1984-08-01

    The present paper briefly reviews the subject of tokamak-stellarator and pinch-stellarator hybrids, and points to two interesting new possibilities: compact-torus-stellarators and mirror-stellarators.

  9. Muscle Synergies of Untrained Subjects during 6 min Maximal Rowing on Slides and Fixed Ergometer

    PubMed Central

    Shaharudin, Shazlin; Zanotto, Damiano; Agrawal, Sunil

    2014-01-01

    The slides ergometer (SE) was an improvisation from fixed ergometer (FE) to bridge the gap of mechanics between ergometer rowing and on-water rowing. The specific mechanical constraints of these two types of ergometers may affect the pattern of muscle recruitment, coordination and adaptation. The main purpose of this study was to evaluate the muscle synergy during 6 minutes maximal rowing on slides (SE) and fixed ergometers (FE). The laterality of muscle synergy was also examined. Surface electromyography activity, power output, heart rate, stroke length and stroke rate were analyzed from nine physically active subjects to assess the rowing performance. Physically active subjects, who were not specifically trained in rowing, were chosen to exclude the training effect on muscle synergy. Principal component analysis (PCA) with varimax rotation was applied to extract muscle synergy. Three muscle synergies were sufficient to explain the majority of variance in SE (94.4 ± 2.2 %) and FE (92.8 ± 1.7 %). Subjects covered more rowing distance, exerted greater power output and attained higher maximal heart rate during rowing on SE than on FE. The results proved the flexibility of muscle synergy to adapt to the mechanical constraints. Rowing on SE emphasized on bi-articular muscles contrary to rowing on FE which relied on cumulative effect of trunk and upper limb muscles during propulsive phase. Key points Three muscle synergies were extracted during maximal rowing on both fixed and slides ergometer Untrained subjects emphasized leg muscles while rowing on SE Untrained subjects focused on back muscles during FE rowing PMID:25435771

  10. Muscle Synergies Heavily Influence the Neural Control of Arm Endpoint Stiffness and Energy Consumption

    PubMed Central

    Inouye, Joshua M.; Valero-Cuevas, Francisco J.

    2016-01-01

    Much debate has arisen from research on muscle synergies with respect to both limb impedance control and energy consumption. Studies of limb impedance control in the context of reaching movements and postural tasks have produced divergent findings, and this study explores whether the use of synergies by the central nervous system (CNS) can resolve these findings and also provide insights on mechanisms of energy consumption. In this study, we phrase these debates at the conceptual level of interactions between neural degrees of freedom and tasks constraints. This allows us to examine the ability of experimentally-observed synergies—correlated muscle activations—to control both energy consumption and the stiffness component of limb endpoint impedance. In our nominal 6-muscle planar arm model, muscle synergies and the desired size, shape, and orientation of endpoint stiffness ellipses, are expressed as linear constraints that define the set of feasible muscle activation patterns. Quadratic programming allows us to predict whether and how energy consumption can be minimized throughout the workspace of the limb given those linear constraints. We show that the presence of synergies drastically decreases the ability of the CNS to vary the properties of the endpoint stiffness and can even preclude the ability to minimize energy. Furthermore, the capacity to minimize energy consumption—when available—can be greatly affected by arm posture. Our computational approach helps reconcile divergent findings and conclusions about task-specific regulation of endpoint stiffness and energy consumption in the context of synergies. But more generally, these results provide further evidence that the benefits and disadvantages of muscle synergies go hand-in-hand with the structure of feasible muscle activation patterns afforded by the mechanics of the limb and task constraints. These insights will help design experiments to elucidate the interplay between synergies and the

  11. Muscle Synergies of Untrained Subjects during 6 min Maximal Rowing on Slides and Fixed Ergometer.

    PubMed

    Shaharudin, Shazlin; Zanotto, Damiano; Agrawal, Sunil

    2014-12-01

    The slides ergometer (SE) was an improvisation from fixed ergometer (FE) to bridge the gap of mechanics between ergometer rowing and on-water rowing. The specific mechanical constraints of these two types of ergometers may affect the pattern of muscle recruitment, coordination and adaptation. The main purpose of this study was to evaluate the muscle synergy during 6 minutes maximal rowing on slides (SE) and fixed ergometers (FE). The laterality of muscle synergy was also examined. Surface electromyography activity, power output, heart rate, stroke length and stroke rate were analyzed from nine physically active subjects to assess the rowing performance. Physically active subjects, who were not specifically trained in rowing, were chosen to exclude the training effect on muscle synergy. Principal component analysis (PCA) with varimax rotation was applied to extract muscle synergy. Three muscle synergies were sufficient to explain the majority of variance in SE (94.4 ± 2.2 %) and FE (92.8 ± 1.7 %). Subjects covered more rowing distance, exerted greater power output and attained higher maximal heart rate during rowing on SE than on FE. The results proved the flexibility of muscle synergy to adapt to the mechanical constraints. Rowing on SE emphasized on bi-articular muscles contrary to rowing on FE which relied on cumulative effect of trunk and upper limb muscles during propulsive phase. Key pointsThree muscle synergies were extracted during maximal rowing on both fixed and slides ergometerUntrained subjects emphasized leg muscles while rowing on SEUntrained subjects focused on back muscles during FE rowing. PMID:25435771

  12. Space-Derived Transparency: Players, Policies, Implications, and Synergies

    NASA Astrophysics Data System (ADS)

    Kinnan, C. J.

    2001-06-01

    Space-derived transparency will become a common means of monitoring, preventing, and mitigating crises, verifying compliance with treaties and law, and enabling confidence and security building measures. Democratization and globalization, the proliferation of information technologies, the availability of commercial space high-resolution imagery, and the growing influence of NGOs invite this question: What is (space-derived) transparency and what effect does it have on US security policy? Three camps have emerged in the debate -Horaeists who seek to build a transnational society through complete transparency; Preservationists, mostly military, who fear the threat to national security, want to deny most space-derived information to non-traditional/non-state actors; and Synergists who seek to capitalize on the best of both camps. There is evidence suggesting that space-derived transparency is an inevitable trend and will resist even the best means of preservationist control. Space-derived transparency may change the dynamic of the security environment by introducing new players into the policy fomentation and implementation process. These players, if not properly schooled in imagery analysis or the potential effects of their use of misinterpreted space-derived imagery, could force policy makers to make fast, ill-considered decisions in order to respond to incidents. In some cases this fast response will defuse potential crises and in other situations these rushed decisions might result in policies without considering the potential consequences, which could turn incidents into crises. Space-derived transparency is a step forward into the future for each camp . . . the challenge for the United States lies in forging synergies in an increasingly transparent world while maintaining the balance between openness and security.

  13. Collaborative Research. Atmospheric Pressure Microplasma Chemistry-Photon Synergies

    SciTech Connect

    Park, Sung-Jin; Eden, James Gary

    2015-12-01

    Combining the effects of low temperature, atmospheric pressure microplasmas and microplasma photon sources offers the promise of greatly expanding the range of applications for each of them. The plasma sources create active chemical species and these can be activated further by the addition of photons and the associated photochemistry. There are many ways to combine the effects of plasma chemistry and photochemistry, especially if there are multiple phases present. This project combined the construction of appropriate test experimental systems, various spectroscopic diagnostics and mathematical modeling. Through a continuous discussion and co-design process with the UC-Berkeley Team, we have successfully completed the fabrication and testing of all components for a microplasma array-assisted system designed for photon-activated plasma chemistry research. Microcavity plasma lamps capable of generating more than 20 mW/cm2 at 172 nm (Xe dimer) were fabricated with a custom form factor to mate to the plasma chemistry setup, and a lamp was current being installed by the Berkeley team so as to investigate plasma chemistry-photon synergies at a higher photon energy (~7.2 eV) as compared to the UVA treatment that is afforded by UV LEDs operating at 365 nm. In particular, motivated by the promising results from the Berkeley team with UVA treatment, we also produced the first generation of lamps that can generate photons in the 300-370 nm wavelength range. Another set of experiments, conducted under the auspices of this grant, involved the use of plasma microjet arrays. The combination of the photons and excited radicals produced by the plasma column resulted in broad area deactivation of bacteria.

  14. AIDS Vaccines and Preexposure Prophylaxis: Is Synergy Possible?

    PubMed Central

    Excler, Jean-Louis; Rida, Wasima; Priddy, Frances; Gilmour, Jill; McDermott, Adrian B.; Kamali, Anatoli; Anzala, Omu; Mutua, Gaudensia; Sanders, Eduard J.; Koff, Wayne; Berkley, Seth

    2011-01-01

    Abstract While the long-term goal is to develop highly effective AIDS vaccines, first generation vaccines may be only partially effective. Other HIV prevention modalities such as preexposure prophylaxis with antiretrovirals (PrEP) may have limited efficacy as well. The combined administration of vaccine and PrEP (VAXPREP), however, may have a synergistic effect leading to an overall benefit that is greater than the sum of the individual effects. We propose two test-of-concept trial designs for an AIDS vaccine plus oral or topical ARV. In one design, evidence that PrEP reduces the risk of HIV acquisition is assumed to justify offering it to all participants. A two-arm study comparing PrEP alone to VAXPREP is proposed in which 30 to 60 incident infections are observed to assess the additional benefit of vaccination on risk of infection and setpoint viral load. The demonstrated superiority of VAXPREP does not imply vaccine alone is efficacious. Similarly, the lack of superiority does not imply vaccine alone is ineffective, as antagonism could exist between vaccine and PrEP. In the other design, PrEP is assumed not to be in general use. A 2 × 2 factorial design is proposed in which high-risk individuals are randomized to one of four arms: placebo vaccine given with placebo PrEP, placebo vaccine given with PrEP, vaccine given with placebo PrEP, or VAXPREP. Between 60 and 210 infections are required to detect a benefit of vaccination with or without PrEP on risk of HIV acquisition or setpoint viral load, with fewer infections needed when synergy is present. PMID:21043994

  15. Extracting motor synergies from random movements for low-dimensional task-space control of musculoskeletal robots.

    PubMed

    Fu, Kin Chung Denny; Dalla Libera, Fabio; Ishiguro, Hiroshi

    2015-10-01

    In the field of human motor control, the motor synergy hypothesis explains how humans simplify body control dimensionality by coordinating groups of muscles, called motor synergies, instead of controlling muscles independently. In most applications of motor synergies to low-dimensional control in robotics, motor synergies are extracted from given optimal control signals. In this paper, we address the problems of how to extract motor synergies without optimal data given, and how to apply motor synergies to achieve low-dimensional task-space tracking control of a human-like robotic arm actuated by redundant muscles, without prior knowledge of the robot. We propose to extract motor synergies from a subset of randomly generated reaching-like movement data. The essence is to first approximate the corresponding optimal control signals, using estimations of the robot's forward dynamics, and to extract the motor synergies subsequently. In order to avoid modeling difficulties, a learning-based control approach is adopted such that control is accomplished via estimations of the robot's inverse dynamics. We present a kernel-based regression formulation to estimate the forward and the inverse dynamics, and a sliding controller in order to cope with estimation error. Numerical evaluations show that the proposed method enables extraction of motor synergies for low-dimensional task-space control. PMID:26448530

  16. Hybrid Vehicle Technologies and their potential for reducing oil use

    NASA Astrophysics Data System (ADS)

    German, John

    2006-04-01

    Vehicles with hybrid gasoline-electric powertrains are starting to gain market share. Current hybrid vehicles add an electric motor, battery pack, and power electronics to the conventional powertrain. A variety of engine/motor configurations are possible, each with advantages and disadvantages. In general, efficiency is improved due to engine shut-off at idle, capture of energy during deceleration that is normally lost as heat in the brakes, downsizing of the conventional engine, and, in some cases, propulsion on the electric motor alone. Ongoing increases in hybrid market share are dependent on cost reduction, especially the battery pack, efficiency synergies with other vehicle technologies, use of the high electric power to provide features desired by customers, and future fuel price and availability. Potential barriers include historically low fuel prices, high discounting of the fuel savings by new vehicle purchasers, competing technologies, and tradeoffs with other factors desired by customers, such as performance, utility, safety, and luxury features.

  17. Analysis of hand synergies in healthy subjects during bimanual manipulation of various objects

    PubMed Central

    2014-01-01

    Background Hand synergies have been extensively studied over the last few decades. Objectives of such research are numerous. In neuroscience, the aim is to improve the understanding of motor control and its ability to reduce the control dimensionality. In applied research fields like robotics the aim is to build biomimetic hand structures, or in prosthetics to design more performant underactuated replacement hands. Nevertheless, most of the synergy schemes identified to this day have been obtained from grasping experiments performed with one single (generally dominant) hand to objects placed in a given position and orientation in space. Aiming at identifying more generic synergies, we conducted similar experiments on postural synergy identification during bimanual manipulation of various objects in order to avoid the factors due to the extrinsic spatial position of the objects. Methods Ten healthy naive subjects were asked to perform a selected “grasp-give-receive” task with both hands using 9 objects. Subjects were wearing Cyberglove Ⓒ on both hands, allowing a measurement of the joint posture (15 degrees of freedom) of each hand. Postural synergies were then evaluated through Principal Component Analysis (PCA). Matches between the identified Principal Components and the human hand joints were analyzed thanks to the correlation matrix. Finally, statistical analysis was performed on the data in order to evaluate the effect of some specific variables on the hand synergies: object shape, hand side (i.e., laterality) and role (giving or receiving hand). Results Results on PCs are consistent with previous literature showing that a few principal components might be sufficient to describe a large variety of different grasps. Nevertheless some simple and strong correlations between PCs and clearly identified sets of hand joints were obtained in this study. In addition, these groupings of DoF corresponds to well-defined anatomo-functional finger joints according to

  18. Electromyogram synergy control of a dexterous artificial hand to unscrew and screw objects

    PubMed Central

    2014-01-01

    Background Due to their limited dexterity, it is currently not possible to use a commercially available prosthetic hand to unscrew or screw objects without using elbow and shoulder movements. For these tasks, prosthetic hands function like a wrench, which is unnatural and limits their use in tight working environments. Results from timed rotational tasks with human subjects demonstrate the clinical need for increased dexterity of prosthetic hands, and a clinically viable solution to this problem is presented for an anthropomorphic artificial hand. Methods Initially, a human hand motion analysis was performed during a rotational task. From these data, human hand synergies were derived and mapped to an anthropomorphic artificial hand. The synergy for the artificial hand is controlled using conventional dual site electromyogram (EMG) signals. These EMG signals were mapped to the developed synergy to control four joints of the dexterous artificial hand simultaneously. Five limb absent and ten able-bodied test subjects participated in a comparison study to complete a timed rotational task as quickly as possible with their natural hands (except for one subject with a bilateral hand absence), eight commercially available prosthetic hands, and the proposed synergy controller. Each test subject used two to four different artificial hands. Results With the able-bodied subjects, the developed synergy controller reduced task completion time by 177% on average. The limb absent subjects completed the task faster on average than with their own prostheses by 46%. There was a statistically significant improvement in task completion time with the synergy controller for three of the four limb absent participants with integrated prostheses, and was not statistically different for the fourth. Conclusions The proposed synergy controller reduced average task completion time compared to commercially available prostheses. Additionally, the synergy controller is able to function in a small

  19. Reorganization of muscle synergies during multidirectional reaching in the horizontal plane with experimental muscle pain

    PubMed Central

    Muceli, Silvia; Falla, Deborah

    2014-01-01

    Muscle pain induces a complex reorganization of the motor strategy which cannot be fully explained by current theories. We tested the hypothesis that the neural control of muscles during reaching in the presence of nociceptive input is determined by a reorganization of muscle synergies with respect to control conditions. Muscle pain was induced by injection of hypertonic saline into the anterior deltoid muscle of eight men. Electromyographic (EMG) signals were recorded from 12 upper limb muscles as subjects performed a reaching task before (baseline) and after the injection of hypertonic (pain) saline, and after the pain sensation vanished. The EMG envelopes were factorized in muscle synergies, and activation signals extracted for each condition. Nociceptive stimulation resulted in a complex muscle reorganization without changes in the kinematic output. The anterior deltoid muscle activity decreased in all subjects while the changes in other muscles were subject specific. Three synergies sufficed to describe the EMG patterns in each condition, suggesting that reaching movements remain modular in the presence of experimental pain. Muscle reorganization in all subjects was accompanied by a change in the activation signals compatible with a change in the central drive to muscles. One, two or three synergies were shared between the baseline and painful conditions, depending on the subject. These results indicate that nociceptive stimulation may induce a reorganization of modular control in reaching. We speculate that such reorganization may be due to the recruitment of synergies specific to the painful condition. PMID:24453279

  20. Pilot Screening to Determine Antimicrobial Synergies in a Multidrug-Resistant Bacterial Strain Library.

    PubMed

    Kim, Si-Hyun; Park, Chulmin; Chun, Hye-Sun; Lee, Dong-Gun; Choi, Jae-Ki; Lee, Hyo-Jin; Cho, Sung-Yeon; Park, Sun Hee; Choi, Su-Mi; Choi, Jung-Hyun; Yoo, Jin-Hong

    2016-07-01

    With the rise in multidrug-resistant (MDR) bacterial infections, there has been increasing interest in combinations of ≥2 antimicrobial agents with synergistic effects. We established an MDR bacterial strain library to screen for in vitro antimicrobial synergy by using a broth microdilution checkerboard method and high-throughput luciferase-based bacterial cell viability assay. In total, 39 MDR bacterial strains, including 23 carbapenem-resistant gram-negative bacteria, 9 vancomycin-intermediate Staphylococcus aureus, and 7 vancomycin-resistant Enterococcus faecalis, were used to screen for potential antimicrobial synergies. Synergies were more frequently identified with combinations of imipenem plus trimethoprim-sulfamethoxazole for carbapenem-resistant Acinetobacter baumannii in the library. To verify this finding, we tested 34 A. baumannii clinical isolates resistant to both imipenem and trimethoprim-sulfamethoxazole by the checkerboard method. The imipenem plus trimethoprim-sulfamethoxazole combination showed synergy in the treatment of 21 (62%) of the clinical isolates. The results indicate that pilot screening for antimicrobial synergy in the MDR bacterial strain library could be valuable in the selection of combination therapeutic regimens to treat MDR bacterial infections. Further studies are warranted to determine whether this screening system can be useful to screen for the combined effects of conventional antimicrobials and new-generation antimicrobials or nonantimicrobials. PMID:26974861

  1. Pilot Screening to Determine Antimicrobial Synergies in a Multidrug-Resistant Bacterial Strain Library

    PubMed Central

    Kim, Si-Hyun; Park, Chulmin; Chun, Hye-Sun; Choi, Jae-Ki; Lee, Hyo-Jin; Cho, Sung-Yeon; Park, Sun Hee; Choi, Su-Mi; Choi, Jung-Hyun; Yoo, Jin-Hong

    2016-01-01

    With the rise in multidrug-resistant (MDR) bacterial infections, there has been increasing interest in combinations of ≥2 antimicrobial agents with synergistic effects. We established an MDR bacterial strain library to screen for in vitro antimicrobial synergy by using a broth microdilution checkerboard method and high-throughput luciferase-based bacterial cell viability assay. In total, 39 MDR bacterial strains, including 23 carbapenem-resistant gram-negative bacteria, 9 vancomycin-intermediate Staphylococcus aureus, and 7 vancomycin-resistant Enterococcus faecalis, were used to screen for potential antimicrobial synergies. Synergies were more frequently identified with combinations of imipenem plus trimethoprim–sulfamethoxazole for carbapenem-resistant Acinetobacter baumannii in the library. To verify this finding, we tested 34 A. baumannii clinical isolates resistant to both imipenem and trimethoprim–sulfamethoxazole by the checkerboard method. The imipenem plus trimethoprim–sulfamethoxazole combination showed synergy in the treatment of 21 (62%) of the clinical isolates. The results indicate that pilot screening for antimicrobial synergy in the MDR bacterial strain library could be valuable in the selection of combination therapeutic regimens to treat MDR bacterial infections. Further studies are warranted to determine whether this screening system can be useful to screen for the combined effects of conventional antimicrobials and new-generation antimicrobials or nonantimicrobials. PMID:26974861

  2. Reaction null-space filter: extracting reactionless synergies for optimal postural balance from motion capture data.

    PubMed

    Nenchev, D N; Miyamoto, Y; Iribe, H; Takeuchi, K; Sato, D

    2016-06-01

    This paper introduces the notion of a reactionless synergy: a postural variation for a specific motion pattern/strategy, whereby the movements of the segments do not alter the force/moment balance at the feet. Given an optimal initial posture in terms of stability, a reactionless synergy can ensure optimality throughout the entire movement. Reactionless synergies are derived via a dynamical model wherein the feet are regarded to be unfixed. Though in contrast with the conventional fixed-feet models, this approach has the advantage of exhibiting the reactions at the feet explicitly. The dynamical model also facilitates a joint-space decomposition scheme yielding two motion components: the reactionless synergy and an orthogonal complement responsible for the dynamical coupling between the feet and the support. Since the reactionless synergy provides the basis (a feedforward control component) for optimal balance control, it may play an important role when evaluating balance abnormalities or when assessing optimality in balance control. We show how to apply the proposed method for analysis of motion capture data obtained from three voluntary movement patterns in the sagittal plane: squat, sway, and forward bend. PMID:26273732

  3. Climate Change Mitigation and Adaptation in the Land Use Sector: From Complementarity to Synergy

    NASA Astrophysics Data System (ADS)

    Duguma, Lalisa A.; Minang, Peter A.; van Noordwijk, Meine

    2014-09-01

    Currently, mitigation and adaptation measures are handled separately, due to differences in priorities for the measures and segregated planning and implementation policies at international and national levels. There is a growing argument that synergistic approaches to adaptation and mitigation could bring substantial benefits at multiple scales in the land use sector. Nonetheless, efforts to implement synergies between adaptation and mitigation measures are rare due to the weak conceptual framing of the approach and constraining policy issues. In this paper, we explore the attributes of synergy and the necessary enabling conditions and discuss, as an example, experience with the Ngitili system in Tanzania that serves both adaptation and mitigation functions. An in-depth look into the current practices suggests that more emphasis is laid on complementarity—i.e., mitigation projects providing adaptation co-benefits and vice versa rather than on synergy. Unlike complementarity, synergy should emphasize functionally sustainable landscape systems in which adaptation and mitigation are optimized as part of multiple functions. We argue that the current practice of seeking co-benefits (complementarity) is a necessary but insufficient step toward addressing synergy. Moving forward from complementarity will require a paradigm shift from current compartmentalization between mitigation and adaptation to systems thinking at landscape scale. However, enabling policy, institutional, and investment conditions need to be developed at global, national, and local levels to achieve synergistic goals.

  4. Task constraints and minimization of muscle effort result in a small number of muscle synergies during gait

    PubMed Central

    De Groote, Friedl; Jonkers, Ilse; Duysens, Jacques

    2014-01-01

    Finding muscle activity generating a given motion is a redundant problem, since there are many more muscles than degrees of freedom. The control strategies determining muscle recruitment from a redundant set are still poorly understood. One theory of motor control suggests that motion is produced through activating a small number of muscle synergies, i.e., muscle groups that are activated in a fixed ratio by a single input signal. Because of the reduced number of input signals, synergy-based control is low dimensional. But a major criticism on the theory of synergy-based control of muscles is that muscle synergies might reflect task constraints rather than a neural control strategy. Another theory of motor control suggests that muscles are recruited by optimizing performance. Optimization of performance has been widely used to calculate muscle recruitment underlying a given motion while assuming independent recruitment of muscles. If synergies indeed determine muscle recruitment underlying a given motion, optimization approaches that do not model synergy-based control could result in muscle activations that do not show the synergistic muscle action observed through electromyography (EMG). If, however, synergistic muscle action results from performance optimization and task constraints (joint kinematics and external forces), such optimization approaches are expected to result in low-dimensional synergistic muscle activations that are similar to EMG-based synergies. We calculated muscle recruitment underlying experimentally measured gait patterns by optimizing performance assuming independent recruitment of muscles. We found that the muscle activations calculated without any reference to synergies can be accurately explained by on average four synergies. These synergies are similar to EMG-based synergies. We therefore conclude that task constraints and performance optimization explain synergistic muscle recruitment from a redundant set of muscles. PMID:25278871

  5. Nonadiabatic molecular dynamics simulations: synergies between theory and experiments.

    PubMed

    Tavernelli, Ivano

    2015-03-17

    Recent developments in nonadiabatic dynamics enabled ab inito simulations of complex ultrafast processes in the condensed phase. These advances have opened new avenues in the study of many photophysical and photochemical reactions triggered by the absorption of electromagnetic radiation. In particular, theoretical investigations can be combined with the most sophisticated femtosecond experimental techniques to guide the interpretation of measured time-resolved observables. At the same time, the availability of experimental data at high (spatial and time) resolution offers a unique opportunity for the benchmarking and the improvement of those theoretical models used to describe complex molecular systems in their natural environment. The established synergy between theory and experiments can produce a better understanding of new ultrafast physical and chemical processes at atomistic scale resolution. Furthermore, reliable ab inito molecular dynamics simulations can already be successfully employed as predictive tools to guide new experiments as well as the design of novel and better performing materials. In this paper, I will give a concise account on the state of the art of molecular dynamics simulations of complex molecular systems in their excited states. The principal aim of this approach is the description of a given system of interest under the most realistic ambient conditions including all environmental effects that influence experiments, for instance, the interaction with the solvent and with external time-dependent electric fields, temperature, and pressure. To this end, time-dependent density functional theory (TDDFT) is among the most efficient and accurate methods for the representation of the electronic dynamics, while trajectory surface hopping gives a valuable representation of the nuclear quantum dynamics in the excited states (including nonadiabatic effects). Concerning the environment and its effects on the dynamics, the quantum mechanics

  6. A synergy-based hand control is encoded in human motor cortical areas.

    PubMed

    Leo, Andrea; Handjaras, Giacomo; Bianchi, Matteo; Marino, Hamal; Gabiccini, Marco; Guidi, Andrea; Scilingo, Enzo Pasquale; Pietrini, Pietro; Bicchi, Antonio; Santello, Marco; Ricciardi, Emiliano

    2016-01-01

    How the human brain controls hand movements to carry out different tasks is still debated. The concept of synergy has been proposed to indicate functional modules that may simplify the control of hand postures by simultaneously recruiting sets of muscles and joints. However, whether and to what extent synergic hand postures are encoded as such at a cortical level remains unknown. Here, we combined kinematic, electromyography, and brain activity measures obtained by functional magnetic resonance imaging while subjects performed a variety of movements towards virtual objects. Hand postural information, encoded through kinematic synergies, were represented in cortical areas devoted to hand motor control and successfully discriminated individual grasping movements, significantly outperforming alternative somatotopic or muscle-based models. Importantly, hand postural synergies were predicted by neural activation patterns within primary motor cortex. These findings support a novel cortical organization for hand movement control and open potential applications for brain-computer interfaces and neuroprostheses. PMID:26880543

  7. Spatiotemporal neuromodulation therapies engaging muscle synergies improve motor control after spinal cord injury.

    PubMed

    Wenger, Nikolaus; Moraud, Eduardo Martin; Gandar, Jerome; Musienko, Pavel; Capogrosso, Marco; Baud, Laetitia; Le Goff, Camille G; Barraud, Quentin; Pavlova, Natalia; Dominici, Nadia; Minev, Ivan R; Asboth, Leonie; Hirsch, Arthur; Duis, Simone; Kreider, Julie; Mortera, Andrea; Haverbeck, Oliver; Kraus, Silvio; Schmitz, Felix; DiGiovanna, Jack; van den Brand, Rubia; Bloch, Jocelyne; Detemple, Peter; Lacour, Stéphanie P; Bézard, Erwan; Micera, Silvestro; Courtine, Grégoire

    2016-02-01

    Electrical neuromodulation of lumbar segments improves motor control after spinal cord injury in animal models and humans. However, the physiological principles underlying the effect of this intervention remain poorly understood, which has limited the therapeutic approach to continuous stimulation applied to restricted spinal cord locations. Here we developed stimulation protocols that reproduce the natural dynamics of motoneuron activation during locomotion. For this, we computed the spatiotemporal activation pattern of muscle synergies during locomotion in healthy rats. Computer simulations identified optimal electrode locations to target each synergy through the recruitment of proprioceptive feedback circuits. This framework steered the design of spatially selective spinal implants and real-time control software that modulate extensor and flexor synergies with precise temporal resolution. Spatiotemporal neuromodulation therapies improved gait quality, weight-bearing capacity, endurance and skilled locomotion in several rodent models of spinal cord injury. These new concepts are directly translatable to strategies to improve motor control in humans. PMID:26779815

  8. Effect of acute noxious stimulation to the leg or back on muscle synergies during walking.

    PubMed

    van den Hoorn, Wolbert; Hodges, Paul W; van Dieën, Jaap H; Hug, François

    2015-01-01

    This study aimed to examine how acute muscle pain affects muscle coordination during gait with consideration of muscle synergies (i.e., group of muscles activated in synchrony), amplitude of muscle activity and kinematics. A secondary aim was to determine whether any adaptation was specific to pain location. Sixteen participants walked on a treadmill during 5 conditions [control, low back pain (LBP), washout LBP, calf pain (CalfP), and washout CalfP]. Five muscle synergies were identified for all of the conditions. Cross-validation analysis showed that muscle synergy vectors extracted for the control condition accounted for >81% of variance accounted for from the other conditions. Muscle synergies were altered very little in some participants (n = 7 for LBP; n = 10 for CalfP), but were more affected in the others (n = 9 for LBP; n = 6 for CalfP). No systematic differences between pain locations were observed. Considering all participants, synergies related to propulsion and weight acceptance were largely unaffected by pain, whereas synergies related to other functions (trunk control and leg deceleration) were more affected. Gastrocnemii activity was less during both CalfP and LBP than control. Soleus activity was further reduced during CalfP, and this was associated with reduced plantar flexion. Some lower leg muscles exhibited adaptations depending on pain location (e.g., greater vastus lateralis and rectus femoris activity during CalfP than LBP). Overall, these changes in muscle coordination involve a participant-specific strategy that is important to further explore, as it may explain why some people are more likely to develop persistence of a painful condition. PMID:25298391

  9. Pharmacological synergy: the next frontier on therapeutic advancement for migraine.

    PubMed

    Blumenfeld, Andrew; Gennings, Chris; Cady, Roger

    2012-04-01

    mechanisms are involved in terminating acute episodes of migraine. Clinicians now capitalize on this observation and use migraine medication in combination with another to improve patient outcomes, for example, using an antiemetic with an opioid or a triptan and NSAIDs. More recently, the Food and Drug Adminstration has approved a combination product containing 85mg of sumatriptan plus 500mg of naproxen sodium for acute treatment of migraine. Clinical trials conducted prior to approval demonstrated that the combination of sumatriptan and naproxen was more effective as a migraine abortive than either of its components but that each component and the combination were more effective than placebo. Exactly how sumatriptan and naproxen interact to create therapeutic synergism is unknown though its mere occurrence suggests that models assisting medical understanding and prediction of pharmacological synergism may improve clinical outcome over products acting through a single receptor mechanism. Migraine is a syndrome, meaning it is defined by observed symptoms rather than known pathophysiology. Multiple pathogenic mechanisms are likely involved in generating this diverse array of symptoms understood as the migraine symptom complex. Sumatriptan and naproxen have independent mechanisms of action and target distinct aspects of the vascular and inflammatory processes hypothesized to underlie migraine. Sumatriptan acts on the 5-HT(1B) and 5-HT(1D) receptors, whereas naproxen inhibits the COX-1 and COX-2 enzymes. Sumatriptan has vasoconstricting effects as well as effects on neurogenic inflammation by decreasing the release of substance P and calcitonin gene-related peptide. In contrast, naproxen affects prostaglandins and other inflammatory mediators. Because sumatriptan and naproxen both relieve migraine yet interact with different cellular targets within the migraine pathway, it is reasonable to assume there is a unique synergy between these medications that improves treatment

  10. Anticipatory synergy adjustments: Preparing a quick action in an unknown direction

    PubMed Central

    Zhou, Tao; Wu, Yen-Hsun; Bartsch, Angelo; Cuadra, Cristian; Zatsiorsky, Vladimir M.; Latash, Mark L.

    2013-01-01

    We studied a mechanism of feed-forward control of a multi-finger action, namely anticipatory synergy adjustments (ASAs) prior to a quick force correction in response to a change in the gain of the visual feedback. Synergies were defined as co-varied across trials adjustments of commands to fingers that stabilized (decreased variance of) the total force. We hypothesized that ASAs would be highly sensitive to prior information about the timing of the action but not to information on its direction, i.e., on whether the gain would go up or down. The subjects produced accurate constant total force by pressing with four fingers on individual force sensors. The feedback signal could change from veridical (the sum of finger forces) to modified, with the middle finger force multiplied by 0.2 or by 1.8. The timing of the gain change and its direction could be known or unknown to the subject in advance. When the timing of the gain change was known, ASA was seen as a drop in the synergy index starting about 250–300 ms prior to the first visible correction of the total force. When the gain change timing was unknown, ASAs started much later, less than 100 ms prior to the total force correction. The magnitude of synergy index changes was significantly larger under the “time known” conditions. Information on the direction of the visual gain change had no effect on the ASA timing, while the ASA magnitude was somewhat larger when this information was not available to the subject. After the total force correction, the synergy index was significantly larger for the force signal computed using the modified gain values as compared to the synergy index value for the actual total force. We conclude that ASAs represent an important feed-forward motor control mechanism that allows preparing for a quick action even when the direction of the action is not known in advance. The results emphasize the subtle control of multi-finger synergies that are specific to the exact contributions of

  11. Muscle synergies may improve optimization prediction of knee contact forces during walking.

    PubMed

    Walter, Jonathan P; Kinney, Allison L; Banks, Scott A; D'Lima, Darryl D; Besier, Thor F; Lloyd, David G; Fregly, Benjamin J

    2014-02-01

    The ability to predict patient-specific joint contact and muscle forces accurately could improve the treatment of walking-related disorders. Muscle synergy analysis, which decomposes a large number of muscle electromyographic (EMG) signals into a small number of synergy control signals, could reduce the dimensionality and thus redundancy of the muscle and contact force prediction process. This study investigated whether use of subject-specific synergy controls can improve optimization prediction of knee contact forces during walking. To generate the predictions, we performed mixed dynamic muscle force optimizations (i.e., inverse skeletal dynamics with forward muscle activation and contraction dynamics) using data collected from a subject implanted with a force-measuring knee replacement. Twelve optimization problems (three cases with four subcases each) that minimized the sum of squares of muscle excitations were formulated to investigate how synergy controls affect knee contact force predictions. The three cases were: (1) Calibrate+Match where muscle model parameter values were calibrated and experimental knee contact forces were simultaneously matched, (2) Precalibrate+Predict where experimental knee contact forces were predicted using precalibrated muscle model parameters values from the first case, and (3) Calibrate+Predict where muscle model parameter values were calibrated and experimental knee contact forces were simultaneously predicted, all while matching inverse dynamic loads at the hip, knee, and ankle. The four subcases used either 44 independent controls or five synergy controls with and without EMG shape tracking. For the Calibrate+Match case, all four subcases closely reproduced the measured medial and lateral knee contact forces (R2 ≥ 0.94, root-mean-square (RMS) error < 66 N), indicating sufficient model fidelity for contact force prediction. For the Precalibrate+Predict and Calibrate+Predict cases, synergy controls yielded better contact force

  12. Determination of in vitro synergy for dual antimicrobial therapy against resistant Neisseria gonorrhoeae using Etest and agar dilution.

    PubMed

    Wind, Carolien M; de Vries, Henry J C; van Dam, Alje P

    2015-03-01

    In response to antimicrobial resistance of Neisseria gonorrhoeae to last-resort extended-spectrum cephalosporins, combination therapy of azithromycin+ceftriaxone is now recommended. Dual therapy can be effective to treat monoresistant strains as well as multidrug-resistant strains, preferably employing the effect of in vitro synergy. As reports on in vitro synergy of azithromycin+ceftriaxone in N. gonorrhoeae are conflicting, in this study an evaluation of this combination was performed using a cross-wise Etest method and agar dilution. Synergy was defined as a fractional inhibitory concentration index (FICI) of ≤0.5. To identify other dual treatment options for gonorrhoea, in vitro synergy was evaluated for 65 dual antimicrobial combinations using Etest. Azithromycin, cefixime, ceftriaxone, colistin, ertapenem, fosfomycin, gentamicin, minocycline, moxifloxacin, rifampicin, spectinomycin and tigecycline were screened for synergy in all possible combinations. No synergy or antagonism was found for any of the 65 combinations. The geometric mean FICI ranged from 0.82 to 2.00. The mean FICI of azithromycin+ceftriaxone was 1.18 (Etest) and 0.55 (agar dilution). The difference between both methods did not result in a difference in interpretation of synergy. Ceftriaxone-resistant strain F89 was tested in all combinations and no synergy was found for any of them. Most importantly, the ceftriaxone minimum inhibitory concentration of F89 was not decreased below the breakpoint with any concentration of azithromycin. PMID:25532741

  13. School District and University Co-Teaching: Toward Instructional Synergy in an Induction/M.Ed. Program

    ERIC Educational Resources Information Center

    Buczynski, Sandy; Sisserson, Kendra

    2008-01-01

    What happens when a district teacher assumes the role of university student? What happens when two instructors from two different institutions are at the helm of a single graduate-level university course? The duality of these situations is recognized in the notion of what the authors termed "instructional synergy", drawing upon synergy as both…

  14. The effect of parameters of equilibrium-based 3-D biomechanical models on extracted muscle synergies during isometric lumbar exertion.

    PubMed

    Eskandari, A H; Sedaghat-Nejad, E; Rashedi, E; Sedighi, A; Arjmand, N; Parnianpour, M

    2016-04-11

    A hallmark of more advanced models is their higher details of trunk muscles represented by a larger number of muscles. The question is if in reality we control these muscles individually as independent agents or we control groups of them called "synergy". To address this, we employed a 3-D biomechanical model of the spine with 18 trunk muscles that satisfied equilibrium conditions at L4/5, with different cost functions. The solutions of several 2-D and 3-D tasks were arranged in a data matrix and the synergies were computed by using non-negative matrix factorization (NMF) algorithms. Variance accounted for (VAF) was used to evaluate the number of synergies that emerged by the analysis, which were used to reconstruct the original muscle activations. It was showed that four and six muscle synergies were adequate to reconstruct the input data of 2-D and 3-D torque space analysis. The synergies were different by choosing alternative cost functions as expected. The constraints affected the extracted muscle synergies, particularly muscles that participated in more than one functional tasks were influenced substantially. The compositions of extracted muscle synergies were in agreement with experimental studies on healthy participants. The following computational methods show that the synergies can reduce the complexity of load distributions and allow reduced dimensional space to be used in clinical settings. PMID:26747515

  15. Effect of fuel origin on synergy during co-gasification of biomass and coal in CO2.

    PubMed

    Zhang, Yan; Zheng, Yan; Yang, Mingjun; Song, Yongchen

    2016-01-01

    The effect of fuel origin on synergy in coal/biomass blends during co-gasification has been assessed using a congruent-mass thermogravimetry analysis (TGA) method. Results revealed that synergy occurs when ash residuals are formed, followed by an almost complete gasification of biomass. Potassium species in biomass ash play a catalytic role in promoting gasification reactivity of coal char, which is a direct consequence of synergy during co-gasification. The SEM-EDS spectra provided conclusive evidence that the transfer of potassium from biomass to the surface of coal char occurs during co-pyrolysis/gasification. Biomass ash rich in silica eliminated synergy in coal/biomass blends but not to the extent of inhibiting the reaction rate of the blended chars to make it slower than that of separated ones. The best result in terms of synergy was concluded to be the combination of low-ash coal and K-rich biomass. PMID:26580896

  16. Prehension Synergies during Smooth Changes of the External Torque

    PubMed Central

    Sun, Yao; Park, Jaebum; Zatsiorsky, Vladimir M.; Latash, Mark L.

    2011-01-01

    We studied characteristics of digit action and their co-variation patterns across trials (prehension synergies) during static holding of an object while the external torque could change slowly and smoothly. The subjects held in the air an instrumented handle with an attachment that allowed a smooth change in the external torque over about 12 s; the load was always kept constant. Series of trials were performed under three conditions: The torque could be zero throughout the trial or it could change slowly requiring a smooth change of the effort from a non-zero pronation value to zero (PR-0) or from a non-zero supination value to zero (SU-0). The handle was kept vertical at all times. Indices of variance and co-variation of elemental variables (forces and moments of force produced by individual digits) stabilizing such performance variables as total normal force, total tangential force, and total moment of force were computed at two levels of an assumed control hierarchy. At the upper level, the task is shared between the thumb and virtual finger (an imagined digit with the mechanical action equal to that of the four fingers), while at the lower level, action of the virtual finger is shared among the actual four fingers. We analyzed the total moment of force as the sum of the moments of force produced by the thumb and virtual finger and also as the sum of the moments of force produced by the normal forces and tangential forces. The results showed that the adjustments in the total moment of force were produced primarily with changes in the moment produced by the virtual finger and by changes in the moment produced by the normal forces. The normal force of the thumb at the final state (which was the same across conditions) was larger in the two conditions with changes in the external torque. The safety margin was significantly higher in the PR-0 condition, and it dropped with the decrease in the external torque. A co-contraction index was computed to reflect moment of

  17. Sensors and OBIA synergy for operational monitoring of surface water

    NASA Astrophysics Data System (ADS)

    Masson, Eric; Thenard, Lucas

    2010-05-01

    , frequent drought period and now with foreseen climate change impacts. This third case will demonstrate the efficiency of SPOT 5 programming in synergy with OBIA methodology to assess the evolution of dam surface water within a complete water cycle (i.e. 2008-09). In all those three cases image segmentation and classification algorithms developed with e-Cognition 8 software allow an easy to use implementation of simple to highly sophisticate OBIA rulsets fully operational in batch processes. Finally this contribution foresees the new opportunity of integration of Worldview 2 multispectral imagery (i.e. 8 bands) including its "coastal" band that will also find an application in continental surface water bathymetry. Worldview 2 is a recently launch satellite (e.g. October 2009) that starts to collect earth observation data since January 2010. It is therefore a promising new remote sensing tool to develop operational hydrology in combination high resolution SAR imagery and OBIA methodology. This contribution will conclude on the strong potential for operationalisation in hydrology and water resources management that recent and future sensors and image analysis methodologies are offering to water management and decision makers.

  18. Hybridization of XRF/XPS and scatterometry for Cu CMP process control

    NASA Astrophysics Data System (ADS)

    L'Herron, Benoit; Chao, Robin; Kim, Kwanghoon; Lee, Wei Ti; Motoyama, Koichi; Deprospo, Bartlet; Standaert, Theodorus; Gaudiello, John; Goldberg, Cindy

    2015-03-01

    This paper demonstrates the synergy between X-rays techniques and scatterometry, and the benefits to combine the data to improve the accuracy and precision for in-line metrology. Particular example is given to show that the hybridization addresses the challenges of aggressive patterning. In 10nm node back-end-of-line (BEOL) integration, we show that the hybridized data between scatterometry and simultaneous X-Ray Fluorescence (XRF) and X-ray Photoelectron Spectroscopy (XPS) provided the closest dimensional correlation to TEM results compared to the individual technique and CDSEM.

  19. Synergy, Holistic Education and R. Buckminster Fuller: Education for a World in Transformation.

    ERIC Educational Resources Information Center

    Gerber, Alex

    This pamphlet relates this quotation by R. Buckminster Fuller to the educational process: "To be optimally effective, undertake at outset the most comprehensive task in the most comprehensive and incisively detailed manner." The principle of synergy can be used to determine when something is "optimally effective." One example of how teachers can…

  20. Synergy against fungal pathogens: working together is better than working alone.

    PubMed

    Musiol, R; Mrozek-Wilczkiewicz, A; Polanski, J

    2014-03-01

    Opportunistic fungi are the most important pathogens in modern world. They are responsible for severe infections in majority of immunocompromised patients. These microorganisms are commonly present in our environment which is natural reservoir of new, resistant species. For this reason mycoses are mainly chronic or long-lasting diseases. Our arsenal of antifungal drugs is growing but still insufficient for emerging resistant pathogens. An alternative for novel chemical entity drugs is the multidrug approach. This exploiting the drugs being currently on market applying simultaneously for better efficacy or to eradicate resistance. Synergy is the term that describes the phenomenon of increased potency of two or more drugs administered in combination. In the last decades it gains more interest and numbers of synergy claimed reports is growing exponentially. However these have rather low impact on clinical trials or practical use of antimycotics. In present review we wish to discuss current status of synergy between antifungal drugs. Both theoretical point of view and practical applicability in clinical terms are covered. There are serious differences between the assumptions, methods and interpretations of the results and sometimes even obvious mistakes in the procedure that was applied or in the outcomes discussed. On the other hands the specificity of fungal infections introduce dozens of factors affecting the observed results. Shift form in vitro studies to clinical trials reveals further difficulties. Hopefully multi-drug approach seems to be effective even if no strong synergy is displayed. PMID:24350847

  1. Synergy in Urban Relationships--Public School Adult Education, Community Colleges, and Community Education.

    ERIC Educational Resources Information Center

    Griffith, William S.

    The presentation reviews selected developments in inter-organizational cooperation and coordination at the local, State, and national levels in order to provide a basis for identifying major questions and issues faced by the National Council of Urban Administrators of Adult Education (NCUAAE) as they strive for synergy in adult education. Trends…

  2. Educational Opportunities Based on the University-Industry Synergies in an Open Innovation Framework

    ERIC Educational Resources Information Center

    Lucia, Oscar; Burdio, Jose M.; Acero, Jesus; Barragan, Luis A.; Garcia, Jose R.

    2012-01-01

    Collaboration between Industry and University is becoming more important in order to improve the competitiveness of the research and development activities. Moreover, establishing synergies to bridge the gap between the academic and industrial spheres has demonstrated to be advantageous for both of them. Nowadays, Industry is moving towards an…

  3. The development of motor synergies in children: Ultrasound and acoustic measurements

    PubMed Central

    Noiray, Aude; Ménard, Lucie; Iskarous, Khalil

    2013-01-01

    The present study focuses on differences in lingual coarticulation between French children and adults. The specific question pursued is whether 4–5 year old children have already acquired a synergy observed in adults in which the tongue back helps the tip in the formation of alveolar consonants. Locus equations, estimated from acoustic and ultrasound imaging data were used to compare coarticulation degree between adults and children and further investigate differences in motor synergy between the front and back parts of the tongue. Results show similar slope and intercept patterns for adults and children in both the acoustic and articulatory domains, with an effect of place of articulation in both groups between alveolar and non-alveolar consonants. These results suggest that 4–5 year old children (1) have learned the motor synergy investigated and (2) have developed a pattern of coarticulatory resistance depending on a consonant place of articulation. Also, results show that acoustic locus equations can be used to gauge the presence of motor synergies in children. PMID:23297916

  4. Diversity and Synergy? The International Context of the English Literacy Strategy.

    ERIC Educational Resources Information Center

    Beard, Roger

    This paper builds upon the "Review of Research and Other Related Evidence" that was commissioned for the government of the United Kingdom's National Literacy Strategy and also upon a subsequent review of international research evidence on children's writing. The paper suggests how "synergy" (combined effect) may be created by linking previously…

  5. Forging Our Own Path: Building Synergy from Opposing Forces: Response to Pomerenke and Rogers.

    ERIC Educational Resources Information Center

    Thomas, Gail Fann

    2001-01-01

    Suggests that educators view teaching and research, ivory tower and "the trenches," positivism and interpretive studies, English and business, theory and practice as two sides of the same coin; that coin is business communication. Addresses three integrative themes: (1) the synergy of scholarships; (2) the dilemma of disciplinary biases; and (3) a…

  6. Real-Time Task Discrimination for Myoelectric Control Employing Task-Specific Muscle Synergies.

    PubMed

    Rasool, Ghulam; Iqbal, Kamran; Bouaynaya, Nidhal; White, Gannon

    2016-01-01

    We present a novel formulation that employs task-specific muscle synergies and state-space representation of neural signals to tackle the challenging myoelectric control problem for lower arm prostheses. The proposed framework incorporates information about muscle configurations, e.g., muscles acting synergistically or in agonist/antagonist pairs, using the hypothesis of muscle synergies. The synergy activation coefficients are modeled as the latent system state and are estimated using a constrained Kalman filter. These task-dependent synergy activation coefficients are estimated in real-time from the electromyogram (EMG) data and are used to discriminate between various tasks. The task discrimination is helped by a post-processing algorithm that uses posterior probabilities. The proposed algorithm is robust as well as computationally efficient, yielding a decision with > 90% discrimination accuracy in approximately 3 ms . The real-time performance and controllability of the algorithm were evaluated using the targeted achievement control (TAC) test. The proposed algorithm outperformed common machine learning algorithms for single- as well as multi-degree-of-freedom (DOF) tasks in both off-line discrimination accuracy and real-time controllability (p < 0.01). PMID:25769166

  7. Synergy between methylerythritol phosphate pathway and mevalonate pathway for isoprene production in Escherichia coli.

    PubMed

    Yang, Chen; Gao, Xiang; Jiang, Yu; Sun, Bingbing; Gao, Fang; Yang, Sheng

    2016-09-01

    Isoprene, a key building block of synthetic rubber, is currently produced entirely from petrochemical sources. In this work, we engineered both the methylerythritol phosphate (MEP) pathway and the mevalonate (MVA) pathway for isoprene production in E. coli. The synergy between the MEP pathway and the MVA pathway was demonstrated by the production experiment, in which overexpression of both pathways improved the isoprene yield about 20-fold and 3-fold, respectively, compared to overexpression of the MEP pathway or the MVA pathway alone. The (13)C metabolic flux analysis revealed that simultaneous utilization of the two pathways resulted in a 4.8-fold increase in the MEP pathway flux and a 1.5-fold increase in the MVA pathway flux. The synergy of the dual pathway was further verified by quantifying intracellular flux responses of the MEP pathway and the MVA pathway to fosmidomycin treatment and mevalonate supplementation. Our results strongly suggest that coupling of the complementary reducing equivalent demand and ATP requirement plays an important role in the synergy of the dual pathway. Fed-batch cultivation of the engineered strain overexpressing the dual pathway resulted in production of 24.0g/L isoprene with a yield of 0.267g/g of glucose. The synergy of the MEP pathway and the MVA pathway also successfully increased the lycopene productivity in E. coli, which demonstrates that it can be used to improve the production of a broad range of terpenoids in microorganisms. PMID:27174717

  8. Neoliberalism, New Public Management and the Sustainable Development Agenda of Higher Education: History, Contradictions and Synergies

    ERIC Educational Resources Information Center

    Bessant, Sophie E. F.; Robinson, Zoe P.; Ormerod, R. Mark

    2015-01-01

    This paper explores the ideological and the practical relationship between neoliberalism and New Public Management (NPM) and the sustainable development agenda of western higher education. Using the United Kingdom and specifically English universities as an example, it investigates the contradictions and the synergies between neoliberal and NPM…

  9. Mechanical Analysis and Hierarchies of Multi-digit Synergies during Accurate Object Rotation

    PubMed Central

    Zhang, Wei; Olafsdottir, Halla B.; Zatsiorsky, Vladimir M.; Latash, Mark L.

    2009-01-01

    We studied the mechanical variables (the grip force and the total moment of force) and multi-digit synergies at two levels (the virtual finger-thumb level, VF-TH, and the individual finger level, IMRL) of a hypothetical control hierarchy during accurate rotation of a hand-held instrumented handle. Synergies were defined as co-varied changes in elemental variables (forces and moments of force) that stabilize the output at a particular level. Indices of multi-digit synergies showed higher values at the hierarchically higher level (VF-TH) for both normal and tangential forces. The moment of force was stabilized at both hierarchical levels during the steady-state phases but not during the movement. The results support the principles of superposition and of mechanical advantage. They also support an earlier hypothesis on an inherent trade-off between synergies at the two hierarchical levels, although the controller showed more subtle and versatile synergic control than the one hypothesized earlier. PMID:19799165

  10. Stability and Composition of Functional Synergies for Speech Movements in Children with Developmental Speech Disorders

    ERIC Educational Resources Information Center

    Terband, H.; Maassen, B.; van Lieshout, P.; Nijland, L.

    2011-01-01

    The aim of this study was to investigate the consistency and composition of functional synergies for speech movements in children with developmental speech disorders. Kinematic data were collected on the reiterated productions of syllables spa(/spa[image omitted]/) and paas(/pa[image omitted]s/) by 10 6- to 9-year-olds with developmental speech…

  11. Neck rotation modulates flexion synergy torques, indicating an ipsilateral reticulospinal source for impairment in stroke

    PubMed Central

    Drogos, Justin; Carmona, Carolina; Keller, Thierry; Dewald, Julius P. A.

    2012-01-01

    The effect of reticular formation excitability on maximum voluntary torque (MVT) generation and associated muscle activation at the shoulder and elbow was investigated through natural elicitation (active head rotation) of the asymmetric tonic neck reflex (ATNR) in 26 individuals with stroke and 9 age-range-matched controls. Isometric MVT generation at the shoulder and elbow was quantified with the head rotated (face pointing) contralateral and ipsilateral to the paretic (stroke) and dominant (control) arm. Given the dominance of abnormal torque coupling of elbow flexion with shoulder abduction (flexion synergy) in stroke and well-developed animal models demonstrating a linkage between reticular formation and ipsilateral elbow flexors and shoulder abductors, we hypothesized that constituent torques of flexion synergy, specifically elbow flexion and shoulder abduction, would increase with contralateral head rotation. The findings of this investigation support this hypothesis. Increases in MVT for three of four flexion synergy constituents (elbow flexion, shoulder abduction, and shoulder external rotation) were observed during contralateral head rotation only in individuals with stroke. Electromyographic data of the associated muscle coactivations were nonsignificant but are presented for consideration in light of a likely underpowered statistical design for this specific variable. This study not only provides evidence for the reemergence of ATNR following stroke but also indicates a common neuroanatomical link, namely, an increased reliance on ipsilateral reticulospinal pathways, as the likely mechanism underlying the expression of both ATNR and flexion synergy that results in the loss of independent joint control. PMID:22956793

  12. Use of muscle synergies and wavelet transforms to identify fatigue during squatting.

    PubMed

    Smale, Kenneth B; Shourijeh, Mohammad S; Benoit, Daniel L

    2016-06-01

    The objective of this study was to supplement continuous wavelet transforms with muscle synergies in a fatigue analysis to better describe the combination of decreased firing frequency and altered activation profiles during dynamic muscle contractions. Nine healthy young individuals completed the dynamic tasks before and after they squatted with a standard Olympic bar until complete exhaustion. Electromyography (EMG) profiles were analyzed with a novel concatenated non-negative matrix factorization method that decomposed EMG signals into muscle synergies. Muscle synergy analysis provides the activation pattern of the muscles while continuous wavelet transforms output the temporal frequency content of the EMG signals. Synergy analysis revealed subtle changes in two-legged squatting after fatigue while differences in one-legged squatting were more pronounced and included the shift from a general co-activation of muscles in the pre-fatigue state to a knee extensor dominant weighting post-fatigue. Continuous wavelet transforms showed major frequency content decreases in two-legged squatting after fatigue while very few frequency changes occurred in one-legged squatting. It was observed that the combination of methods is an effective way of describing muscle fatigue and that muscle activation patterns play a very important role in maintaining the overall joint kinetics after fatigue. PMID:27156237

  13. Synergy of Streptogramin Antibiotics Occurs Independently of Their Effects on Translation

    PubMed Central

    Noeske, Jonas; Huang, Jian; Olivier, Nelson B.; Giacobbe, Robert A.; Zambrowski, Mark

    2014-01-01

    Streptogramin antibiotics are divided into types A and B, which in combination can act synergistically. We compared the molecular interactions of the streptogramin combinations Synercid (type A, dalfopristin; type B, quinupristin) and NXL 103 (type A, flopristin; type B, linopristin) with the Escherichia coli 70S ribosome by X-ray crystallography. We further analyzed the activity of the streptogramin components individually and in combination. The streptogramin A and B components in Synercid and NXL 103 exhibit synergistic antimicrobial activity against certain pathogenic bacteria. However, in transcription-coupled translation assays, only combinations that include dalfopristin, the streptogramin A component of Synercid, show synergy. Notably, the diethylaminoethylsulfonyl group in dalfopristin reduces its activity but is the basis for synergy in transcription-coupled translation assays before its rapid hydrolysis from the depsipeptide core. Replacement of the diethylaminoethylsulfonyl group in dalfopristin by a nonhydrolyzable group may therefore be beneficial for synergy. The absence of general streptogramin synergy in transcription-coupled translation assays suggests that the synergistic antimicrobial activity of streptogramins can occur independently of the effects of streptogramin on translation. PMID:24957822

  14. Extended inclusive fitness theory: synergy and assortment drives the evolutionary dynamics in biology and economics.

    PubMed

    Jaffe, Klaus

    2016-01-01

    W.D. Hamilton's Inclusive Fitness Theory explains the conditions that favor the emergence and maintenance of social cooperation. Today we know that these include direct and indirect benefits an agent obtains by its actions, and through interactions with kin and with genetically unrelated individuals. That is, in addition to kin-selection, assortation or homophily, and social synergies drive the evolution of cooperation. An Extended Inclusive Fitness Theory (EIFT) synthesizes the natural selection forces acting on biological evolution and on human economic interactions by assuming that natural selection driven by inclusive fitness produces agents with utility functions that exploit assortation and synergistic opportunities. This formulation allows to estimate sustainable cost/benefit threshold ratios of cooperation among organisms and/or economic agents, using existent analytical tools, illuminating our understanding of the dynamic nature of society, the evolution of cooperation among kin and non-kin, inter-specific cooperation, co-evolution, symbioses, division of labor and social synergies. EIFT helps to promote an interdisciplinary cross fertilization of the understanding of synergy by, for example, allowing to describe the role for division of labor in the emergence of social synergies, providing an integrated framework for the study of both, biological evolution of social behavior and economic market dynamics. Another example is a bio-economic understanding of the motivations of terrorists, which identifies different forms of terrorism. PMID:27468393

  15. The "Synergies" Research-Practice Partnership Project: A "2020 Vision" Case Study

    ERIC Educational Resources Information Center

    Falk, John H.; Dierking, Lynn D.; Staus, Nancy L.; Wyld, Jennifer N.; Bailey, Deborah L.; Penuel, William R.

    2016-01-01

    This paper, describes "Synergies," an on-going longitudinal study and design effort, being conducted in a diverse, under-resourced community in Portland, Oregon, with the goal of measurably improving STEM learning, interest and participation by early adolescents, both in school and out of school. Authors examine how the work of this…

  16. Media Credibility Reconsidered: Synergy between On-Air and Online News.

    ERIC Educational Resources Information Center

    Bucy, Erik P.

    2003-01-01

    Examines the combined effects of on-air and online network news exposure, placing student and adult news consumers in broadcast news, online news, and telewebbing conditions. Indicates that perceptions of network news credibility are affected by channel used. Offers evidence for the existence of a synergy effect between on-air and online news. (PM)

  17. "I've Known Rivers": A Reflection on the Synergy of Multigenre, Multimodal Texts

    ERIC Educational Resources Information Center

    Richter, Elizabeth

    2016-01-01

    In this article an elementary literacy specialist reflects on the use of multigenre, multimodal texts to support the teaching of poetry. She explores the synergy between poetry and related informational, visual, and auditory texts to afford deeper insights into the poem and the poet, in this instance, the poem, "The Negro Speaks of…

  18. Synergy Access: A Global Newsletter on Futuristic Communications, Media & Networking. Number 1.

    ERIC Educational Resources Information Center

    Thomas, Wes, Ed.

    A global newsletter on futuristic communications, media and networking is dedicated to creating open, humanistic environments for better interpersonal communication and to exploring the phenomenon of synergy, the coming together of people, ideas and environments for creation of something greater than the sum of the parts. Editorials, poetry, and…

  19. Effect of handedness on muscle synergies during upper limb planar movements.

    PubMed

    Duthilleul, N; Pirondini, E; Coscia, M; Micera, S

    2015-08-01

    Handedness is a prominent but poorly understood aspect of human motor performances. Despite it is generally accepted that it results from differences in the neural control of the arm, the mechanisms at the origin of the side-difference in motor performances are still unknown. In this work, we propose to deepen this aspect by investigating muscle synergies organization. We obtained muscle synergies through the factorization of the superficial electromyographical (EMG) activity related to fifteen upper limb muscles in the dominant and non-dominant side of 5 healthy young right and left dominant subjects, while executing planar wide and tight circular trajectories. Our preliminary results showed that right and left handed subjects performed the circular trajectories with a different muscle organization. Moreover, a task-related side-difference in muscle synergies was observed. Further investigations in a larger cohort of individuals are necessary to determine the neural mechanisms generating the differences in number and organization of muscle synergies between left and right handed individuals. PMID:26737035

  20. Hybrid microelectronic technology

    NASA Astrophysics Data System (ADS)

    Moran, P.

    Various areas of hybrid microelectronic technology are discussed. The topics addressed include: basic thick film processing, thick film pastes and substrates, add-on components and attachment methods, thin film processing, and design of thick film hybrid circuits. Also considered are: packaging hybrid circuits, automating the production of hybrid circuits, application of hybrid techniques, customer's view of hybrid technology, and quality control and assurance in hybrid circuit production.

  1. Suboptimal Muscle Synergy Activation Patterns Generalize their Motor Function across Postures

    PubMed Central

    Sohn, M. Hongchul; Ting, Lena H.

    2016-01-01

    We used a musculoskeletal model to investigate the possible biomechanical and neural bases of using consistent muscle synergy patterns to produce functional motor outputs across different biomechanical conditions, which we define as generalizability. Experimental studies in cats demonstrate that the same muscle synergies are used during reactive postural responses at widely varying configurations, producing similarly-oriented endpoint force vectors with respect to the limb axis. However, whether generalizability across postures arises due to similar biomechanical properties or to neural selection of a particular muscle activation pattern has not been explicitly tested. Here, we used a detailed cat hindlimb model to explore the set of feasible muscle activation patterns that produce experimental synergy force vectors at a target posture, and tested their generalizability by applying them to different test postures. We used three methods to select candidate muscle activation patterns: (1) randomly-selected feasible muscle activation patterns, (2) optimal muscle activation patterns minimizing muscle effort at a given posture, and (3) generalizable muscle activation patterns that explicitly minimized deviations from experimentally-identified synergy force vectors across all postures. Generalizability was measured by the deviation between the simulated force direction of the candidate muscle activation pattern and the experimental synergy force vectors at the test postures. Force angle deviations were the greatest for the randomly selected feasible muscle activation patterns (e.g., >100°), intermediate for effort-wise optimal muscle activation patterns (e.g., ~20°), and smallest for generalizable muscle activation patterns (e.g., <5°). Generalizable muscle activation patterns were suboptimal in terms of effort, often exceeding 50% of the maximum possible effort (cf. ~5% in minimum-effort muscle activation patterns). The feasible muscle activation ranges of individual

  2. Inference and representations of hand actions through grasping synergies. Comment on "Grasping synergies: A motor-control approach to the mirror neuron mechanism" by D'Ausilio, Bartoli, and Maffongelli

    NASA Astrophysics Data System (ADS)

    Santello, Marco

    2015-03-01

    The concept of synergy, denoting the coordination of multiple elements working together toward a common goal, has been extensively studied to understand how the central nervous system (CNS) controls movement (for review see [5,9]). Although this definition is appealing in its simplicity, 'multiple elements', 'working together', and 'common goal' each take different meanings depending on the scale at which a given sensorimotor system is studied, whether the 'working together' is defined in spatial and/or temporal domains, and the hypothesized synergy's 'common goal'. For example, the elements involved in a synergy can be defined as single motor units, muscles, or joints. Similarly, the goal of a synergy may be defined as a means available to the CNS to 'simplify' the control of multiple elements, or to minimize a given cost function or movement feature - all of which may differ across tasks and tasks conditions. These considerations underscore the fact that a universally accepted definition of synergies and their functional role remains to be established (for review see [6]). Thus, the nature and functional role(s) of synergies is still debated in the literature. Nevertheless, it is generally agreed that the reduction in the number of independent degrees of freedom that is manifested through synergies emerges from the interaction of biomechanical and neural factors constraining the spatial and temporal coordination of multiple muscles.

  3. Are we ready to move beyond the reductionist approach of classical synergy control?. Comment on "Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands" by Marco Santello et al.

    NASA Astrophysics Data System (ADS)

    Lacquaniti, Francesco; Ivanenko, Yuri P.; Zago, Myrka

    2016-07-01

    Starting from the classical concepts introduced by Sherrington [1] and considerably elaborated by Bernstein [2], much has been learned about motor synergies in the last several years. The contributions of the group funded by the European project "The Hand Embodied" are remarkable in the field of biological and robotic control of the hand based on synergies, and they are reflected in this enjoyable review [3]. There, Santello et al. adopt Bernstein's definition of motor synergies as multiple elements working together towards a common goal, with the result that multiple degrees of freedom are controlled within a lower-dimensional space than the available number of dimensions.

  4. On the Origin of Muscle Synergies: Invariant Balance in the Co-activation of Agonist and Antagonist Muscle Pairs

    PubMed Central

    Hirai, Hiroaki; Miyazaki, Fumio; Naritomi, Hiroaki; Koba, Keitaro; Oku, Takanori; Uno, Kanna; Uemura, Mitsunori; Nishi, Tomoki; Kageyama, Masayuki; Krebs, Hermano Igo

    2015-01-01

    Investigation of neural representation of movement planning has attracted the attention of neuroscientists, as it may reveal the sensorimotor transformation essential to motor control. The analysis of muscle synergies based on the activity of agonist–antagonist (AA) muscle pairs may provide insight into such transformations, especially for a reference frame in the muscle space. In this study, we examined the AA concept using the following explanatory variables: the AA ratio, which is related to the equilibrium-joint angle, and the AA sum, which is associated with joint stiffness. We formulated muscle synergies as a function of AA sums, positing that muscle synergies are composite units of mechanical impedance. The AA concept can be regarded as another form of the equilibrium-point (EP) hypothesis, and it can be extended to the concept of EP-based synergies. We introduce, here, a novel tool for analyzing the neurological and motor functions underlying human movements and review some initial insights from our results about the relationships between muscle synergies, endpoint stiffness, and virtual trajectories (time series of EP). Our results suggest that (1) muscle synergies reflect an invariant balance in the co-activation of AA muscle pairs; (2) each synergy represents the basis for the radial, tangential, and null movements of the virtual trajectory in the polar coordinates centered on the specific joint at the base of the body; and (3) the alteration of muscle synergies (for example, due to spasticity or rigidity following neurological injury) results in significant distortion of endpoint stiffness and concomitant virtual trajectories. These results indicate that muscle synergies (i.e., the balance of muscle mechanical impedance) are essential for motor control. PMID:26636079

  5. Hybrid Supramolecular and Colloidal Hydrogels that Bridge Multiple Length Scales†

    PubMed Central

    Janeček, Emma‐Rose; McKee, Jason R.; Tan, Cindy S. Y.; Nykänen, Antti; Kettunen, Marjo; Laine, Janne

    2015-01-01

    Abstract Hybrid nanocomposites were constructed based on colloidal nanofibrillar hydrogels with interpenetrating supramolecular hydrogels, displaying enhanced rheological yield strain and a synergistic improvement in storage modulus. The supramolecular hydrogel consists of naphthyl‐functionalized hydroxyethyl cellulose and a cationic polystyrene derivative decorated with methylviologen moieties, physically cross‐linked with cucurbit[8]uril macrocyclic hosts. Fast exchange kinetics within the supramolecular system are enabled by reversible cross‐linking through the binding of the naphthyl and viologen guests. The colloidal hydrogel consists of nanofibrillated cellulose that combines a mechanically strong nanofiber skeleton with a lateral fibrillar diameter of a few nanometers. The two networks interact through hydroxyethyl cellulose adsorption to the nanofibrillated cellulose surfaces. This work shows methods to bridge the length scales of molecular and colloidal hybrid hydrogels, resulting in synergy between reinforcement and dynamics. PMID:27478263

  6. Hybrid Supramolecular and Colloidal Hydrogels that Bridge Multiple Length Scales**

    PubMed Central

    Janeček, Emma-Rose; McKee, Jason R; Tan, Cindy S Y; Nykänen, Antti; Kettunen, Marjo; Laine, Janne; Ikkala, Olli; Scherman, Oren A

    2015-01-01

    Hybrid nanocomposites were constructed based on colloidal nanofibrillar hydrogels with interpenetrating supramolecular hydrogels, displaying enhanced rheological yield strain and a synergistic improvement in storage modulus. The supramolecular hydrogel consists of naphthyl-functionalized hydroxyethyl cellulose and a cationic polystyrene derivative decorated with methylviologen moieties, physically cross-linked with cucurbit[8]uril macrocyclic hosts. Fast exchange kinetics within the supramolecular system are enabled by reversible cross-linking through the binding of the naphthyl and viologen guests. The colloidal hydrogel consists of nanofibrillated cellulose that combines a mechanically strong nanofiber skeleton with a lateral fibrillar diameter of a few nanometers. The two networks interact through hydroxyethyl cellulose adsorption to the nanofibrillated cellulose surfaces. This work shows methods to bridge the length scales of molecular and colloidal hybrid hydrogels, resulting in synergy between reinforcement and dynamics. PMID:25772264

  7. Hybrid Gear

    NASA Technical Reports Server (NTRS)

    Handschuh, Robert F. (Inventor); Roberts, Gary D. (Inventor)

    2016-01-01

    A hybrid gear consisting of metallic outer rim with gear teeth and metallic hub in combination with a composite lay up between the shaft interface (hub) and gear tooth rim is described. The composite lay-up lightens the gear member while having similar torque carrying capability and it attenuates the impact loading driven noise/vibration that is typical in gear systems. The gear has the same operational capability with respect to shaft speed, torque, and temperature as an all-metallic gear as used in aerospace gear design.

  8. ) Hybrid Composite

    NASA Astrophysics Data System (ADS)

    Show, Bijay Kumar; Mondal, Dipak Kumar; Maity, Joydeep

    2014-12-01

    In this research work, the dry sliding wear behavior of 6351 Al-(4 vol.% SiC + 4 vol.% Al2O3) hybrid composite was investigated at low sliding speed (1 m/s) against a hardened EN 31 disk at different loads. In general, the wear mechanism involved adhesion (along with associated subsurface cracking and delamination) and microcutting abrasion at lower load. While at higher load, abrasive wear involving microcutting and microploughing along with adherent oxide formation was observed. The overall wear rate increased with increasing normal load. The massive particle clusters as well as individual reinforcement particles were found to stand tall to resist abrasive wear. Besides, at higher load, the generation of adherent nodular tribo-oxide through nucleation and epitaxial growth on existing Al2O3 particles lowered down the wear rate. Accordingly, at any normal load, 6351 Al-(4 vol.% SiC + 4 vol.% Al2O3) hybrid composite exhibited superior wear resistance (lower overall wear rate) than the reported wear resistance of monolithic 6351 Al alloy.

  9. Hybrid Simulator

    Energy Science and Technology Software Center (ESTSC)

    2005-10-15

    HybSim (short for Hybrid Simulator) is a flexible, easy to use screening tool that allows the user to quanti the technical and economic benefits of installing a village hybrid generating system and simulates systems with any combination of —Diesel generator sets —Photovoltaic arrays -Wind Turbines and -Battery energy storage systems Most village systems (or small population sites such as villages, remote military bases, small communities, independent or isolated buildings or centers) depend on diesel generationmore » systems for their source of energy. HybSim allows the user to determine other "sources" of energy that can greatly reduce the dollar to kilo-watt hour ratio. Supported by the DOE, Energy Storage Program, HybSim was initially developed to help analyze the benefits of energy storage systems in Alaskan villages. Soon after its development, other sources of energy were added providing the user with a greater range of analysis opportunities and providing the village with potentially added savings. In addition to village systems, HybSim has generated interest for use from military institutions in energy provisions and USAID for international village analysis.« less

  10. Determinants of GH-releasing hormone and GH-releasing peptide synergy in men

    PubMed Central

    Veldhuis, Johannes D.; Bowers, Cyril Y.

    2009-01-01

    Age, sex steroids, and abdominal-visceral fat (AVF) jointly affect pulsatile growth hormone (GH) secretion. Pulsatile GH secretion in turn is controlled by GH-releasing hormone (GHRH), GH-releasing peptide (GHRP), and somatostatin. Marked stimulation of pulsatile GH secretion is achieved via GHRH-GHRP synergy. Nonetheless, how key modulators of GH secretion, such as age, sex steroids, and body mass index, modify GHRH-GHRP synergy is not known. The present strategy was to 1) infuse GHRH and GHRP-2 simultaneously to evoke synergy and 2) downregulate the gonadal axis with leuprolide and then restore placebo (Pl) or testosterone (T) to clamp the sex steroid milieu. Forty-seven men [18–74 yr of age, T = 7–1,950 ng/dl, estradiol (E2) = 5–79 pg/ml, insulin-like growth factor (IGF)-I = 115–817 μg/l, AVF = 11–349 cm2] were studied. GHRH-GHRP synergy correlated negatively with age and AVF (both P < 0.001) and positively with IGF-I (P < 0.001) and IGF-binding protein (IGFBP)-3 (P = 0.031). Unstimulated basal (nonpulsatile) GH secretion correlated positively with T (P = 0.015) and E2 (P = 0.004) concentrations. Fasting pulsatile GH secretion varied negatively with age (P = 0.017) and positively with IGF-I (P = 0.002) and IGFBP-3 (P = 0.001). By stepwise forward-selection multivariate analyses, AVF, IGF-I, and IGFBP-3 together explained 60% of the variability in GHRH-GHRP synergy (P < 0.001), E2 accounted for 17% of the variability in basal GH secretion (P = 0.007), and IGF-I explained 20% of the variability in fasting pulsatile GH secretion (P = 0.002). In conclusion, a paradigm examining GHRH-GHRP synergy under a sex steroid clamp reveals highly selective control of basal, pulsatile, and synergistic peptide-driven GH secretion by AVF, E2, and IGF-I in healthy men. PMID:19240251

  11. Modeling Suggests a Mechanism of Synergy Between Hepatitis C Virus Entry Inhibitors and Drugs of Other Classes

    PubMed Central

    Padmanabhan, P; Dixit, NM

    2015-01-01

    Hepatitis C virus (HCV) entry inhibitors (EIs) act synergistically with drugs targeting other stages of the HCV lifecycle. The origin of this synergy remains unknown. Here, we argue that the synergy may arise from the complementary activities of the drugs across cell subpopulations expressing different levels of HCV entry receptors. We employ mathematical modeling of viral kinetics in vitro, where cells with a distribution of entry receptor expression levels are exposed to HCV with or without drugs. The drugs act independently in each cell, as expected in the absence of underlying interactions. Yet, at the cell population level our model predicts that the drugs exhibit synergy. EIs effectively block infection of cells with low receptor levels. With high receptor levels, where EIs are compromised, other drugs are potent. This novel mechanism of synergy, arising at the cell population level may facilitate interpretation of drug activity and treatment optimization. PMID:26380153

  12. Modeling Suggests a Mechanism of Synergy Between Hepatitis C Virus Entry Inhibitors and Drugs of Other Classes.

    PubMed

    Padmanabhan, P; Dixit, N M

    2015-08-01

    Hepatitis C virus (HCV) entry inhibitors (EIs) act synergistically with drugs targeting other stages of the HCV lifecycle. The origin of this synergy remains unknown. Here, we argue that the synergy may arise from the complementary activities of the drugs across cell subpopulations expressing different levels of HCV entry receptors. We employ mathematical modeling of viral kinetics in vitro, where cells with a distribution of entry receptor expression levels are exposed to HCV with or without drugs. The drugs act independently in each cell, as expected in the absence of underlying interactions. Yet, at the cell population level our model predicts that the drugs exhibit synergy. EIs effectively block infection of cells with low receptor levels. With high receptor levels, where EIs are compromised, other drugs are potent. This novel mechanism of synergy, arising at the cell population level may facilitate interpretation of drug activity and treatment optimization. PMID:26380153

  13. Spinal antinociceptive synergy between clonidine and morphine, U69593, and DPDPE: isobolographic analysis.

    PubMed

    Ossipov, M H; Lozito, R; Messineo, E; Green, J; Harris, S; Lloyd, P

    1990-01-01

    The spinal antinociceptive interaction between the opiate receptor subtype agonists morphine (mu), U69593 (kappa) and [D-Pen2,5]-enkephalin (DPDPE; delta) with clonidine (alpha 2 adrenergic) was examined. Male SD rats received fixed ratios of clonidine to morphine (10:1), U69593 (1:3), or DPDPE (10:1) through catheters terminating at the lumbar cord. Graded dose-response curves (DRC) were constructed from tail-flick latencies converted to % maximal possible effect (%MPE), and the ED50 calculated. The DRCs of morphine and U69593 but not of DPDPE were parallel to the DRC of the opiate plus clonidine. Synergy was determined by isobolographic analysis. The ED50 values for the mixtures were significantly less than the theoretical additive ED50 values, indicating synergy between clonidine and morphine, U69593, or DPDPE. PMID:2250556

  14. EBW-Bootstrap Current Synergy in the National Spherical Torus Experiment (NSTX)

    SciTech Connect

    R.W. Harvey; G. Taylor

    2005-02-02

    Current driven by electron Bernstein waves (EBW) and by the electron bootstrap effect are calculated separately and concurrently with a kinetic code, to determine the degree of synergy between them. A target {beta} = 40% NSTX plasma is examined. A simple bootstrap model in the CQL3D Fokker-Planck code is used in these studies: the transiting electron distributions are connected in velocity-space at the trapped-passing boundary to trapped-electron distributions which are displaced radially by a half-banana width outwards/inwards for the co-/counter-passing regions. This model agrees well with standard bootstrap current calculations, over the outer 60% of the plasma radius. Relatively small synergy net bootstrap current is obtained for EBW power up to 4 MW. Locally, bootstrap current density increases in proportion to increased plasma pressure, and this effect can significantly affect the radial profile of driven current.

  15. Defining the Catechol-Cation Synergy for Enhanced Wet Adhesion to Mineral Surfaces.

    PubMed

    Rapp, Michael V; Maier, Greg P; Dobbs, Howard A; Higdon, Nicholas J; Waite, J Herbert; Butler, Alison; Israelachvili, Jacob N

    2016-07-27

    Mussel foot proteins (Mfps) exhibit remarkably adaptive adhesion and bridging between polar surfaces in aqueous solution despite the strong hydration barriers at the solid-liquid interface. Recently, catechols and amines-two functionalities that account for >50 mol % of the amino acid side chains in surface-priming Mfps-were shown to cooperatively displace the interfacial hydration and mediate robust adhesion between mineral surfaces. Here we demonstrate that (1) synergy between catecholic and guanidinium side chains similarly promotes adhesion, (2) increasing the ratio of cationic amines to catechols in a molecule reduces adhesion, and (3) the catechol-cation synergy is greatest when both functionalities are present within the same molecule. PMID:27415839

  16. The Successful Synergy of Swift and Fermi/GBM in Magnetars

    NASA Technical Reports Server (NTRS)

    Kouveliotou, Chryssa

    2011-01-01

    The magnetar rate of discovery has increased dramatically in the last decade. Five sources were discovered in the last three years alone as a result of the very efficient synergy among three X- and .gamma-ray instruments on NASA satellites: the Swift/Burst Alert Telescope (BAT), the Fermi/Gamma ray Burst Monitor (GBM), and the Rossi X-Ray Timing Explorer; RXTE/Proportional Counter Array (PCA). To date, there are approx. 25 magnetar candidates, of which two are (one each) in the Large and Small Magellanic Cloud and the rest reside on the Galactic plane of our Milky Way. I will discuss here the main properties of the Magnetar Population and the common projects that can be achieved with the synergy of Swift and GBM.

  17. Investigating Conversational Dynamics: Interactive Alignment, Interpersonal Synergy, and Collective Task Performance.

    PubMed

    Fusaroli, Riccardo; Tylén, Kristian

    2016-01-01

    This study investigates interpersonal processes underlying dialog by comparing two approaches, interactive alignment and interpersonal synergy, and assesses how they predict collective performance in a joint task. While the interactive alignment approach highlights imitative patterns between interlocutors, the synergy approach points to structural organization at the level of the interaction-such as complementary patterns straddling speech turns and interlocutors. We develop a general, quantitative method to assess lexical, prosodic, and speech/pause patterns related to the two approaches and their impact on collective performance in a corpus of task-oriented conversations. The results show statistical presence of patterns relevant for both approaches. However, synergetic aspects of dialog provide the best statistical predictors of collective performance and adding aspects of the alignment approach does not improve the model. This suggests that structural organization at the level of the interaction plays a crucial role in task-oriented conversations, possibly constraining and integrating processes related to alignment. PMID:25988263

  18. Hybridized tetraquarks

    NASA Astrophysics Data System (ADS)

    Esposito, A.; Pilloni, A.; Polosa, A. D.

    2016-07-01

    We propose a new interpretation of the neutral and charged X , Z exotic hadron resonances. Hybridized-tetraquarks are neither purely compact tetraquark states nor bound or loosely bound molecules but rather a manifestation of the interplay between the two. While meson molecules need a negative or zero binding energy, its counterpart for h-tetraquarks is required to be positive. The formation mechanism of this new class of hadrons is inspired by that of Feshbach metastable states in atomic physics. The recent claim of an exotic resonance in the Bs0 π± channel by the D0 Collaboration and the negative result presented subsequently by the LHCb Collaboration are understood in this scheme, together with a considerable portion of available data on X , Z particles. Considerations on a state with the same quantum numbers as the X (5568) are also made.

  19. Motoneuronal and muscle synergies involved in cat hindlimb control during fictive and real locomotion: a comparison study.

    PubMed

    Markin, Sergey N; Lemay, Michel A; Prilutsky, Boris I; Rybak, Ilya A

    2012-04-01

    We compared the activity profiles and synergies of spinal motoneurons recorded during fictive locomotion evoked in immobilized decerebrate cat preparations by midbrain stimulation to the activity profiles and synergies of the corresponding hindlimb muscles obtained during forward level walking in cats. The fictive locomotion data were collected in the Spinal Cord Research Centre, University of Manitoba, and provided by Dr. David McCrea; the real locomotion data were obtained in the laboratories of M. A. Lemay and B. I. Prilutsky. Scatterplot representation and minimum spanning tree clustering algorithm were used to identify the possible motoneuronal and muscle synergies operating during both fictive and real locomotion. We found a close similarity between the activity profiles and synergies of motoneurons innervating one-joint muscles during fictive locomotion and the profiles and synergies of the corresponding muscles during real locomotion. However, the activity patterns of proximal nerves controlling two-joint muscles, such as posterior biceps and semitendinosus (PBSt) and rectus femoris (RF), were not uniform in fictive locomotion preparations and differed from the activity profiles of the corresponding two-joint muscles recorded during forward level walking. Moreover, the activity profiles of these nerves and the corresponding muscles were unique and could not be included in the synergies identified in fictive and real locomotion. We suggest that afferent feedback is involved in the regulation of locomotion via motoneuronal synergies controlled by the spinal central pattern generator (CPG) but may also directly affect the activity of motoneuronal pools serving two-joint muscles (e.g., PBSt and RF). These findings provide important insights into the organization of the spinal CPG in mammals, the motoneuronal and muscle synergies engaged during locomotion, and their afferent control. PMID:22190626

  20. Motoneuronal and muscle synergies involved in cat hindlimb control during fictive and real locomotion: a comparison study

    PubMed Central

    Markin, Sergey N.; Lemay, Michel A.; Prilutsky, Boris I.

    2012-01-01

    We compared the activity profiles and synergies of spinal motoneurons recorded during fictive locomotion evoked in immobilized decerebrate cat preparations by midbrain stimulation to the activity profiles and synergies of the corresponding hindlimb muscles obtained during forward level walking in cats. The fictive locomotion data were collected in the Spinal Cord Research Centre, University of Manitoba, and provided by Dr. David McCrea; the real locomotion data were obtained in the laboratories of M. A. Lemay and B. I. Prilutsky. Scatterplot representation and minimum spanning tree clustering algorithm were used to identify the possible motoneuronal and muscle synergies operating during both fictive and real locomotion. We found a close similarity between the activity profiles and synergies of motoneurons innervating one-joint muscles during fictive locomotion and the profiles and synergies of the corresponding muscles during real locomotion. However, the activity patterns of proximal nerves controlling two-joint muscles, such as posterior biceps and semitendinosus (PBSt) and rectus femoris (RF), were not uniform in fictive locomotion preparations and differed from the activity profiles of the corresponding two-joint muscles recorded during forward level walking. Moreover, the activity profiles of these nerves and the corresponding muscles were unique and could not be included in the synergies identified in fictive and real locomotion. We suggest that afferent feedback is involved in the regulation of locomotion via motoneuronal synergies controlled by the spinal central pattern generator (CPG) but may also directly affect the activity of motoneuronal pools serving two-joint muscles (e.g., PBSt and RF). These findings provide important insights into the organization of the spinal CPG in mammals, the motoneuronal and muscle synergies engaged during locomotion, and their afferent control. PMID:22190626

  1. Bihemispheric Transcranial Direct Current Stimulation Enhances Effector-Independent Representations of Motor Synergy and Sequence Learning

    PubMed Central

    Husain, Masud; Wiestler, Tobias; Diedrichsen, Jörn

    2014-01-01

    Complex manual tasks—everything from buttoning up a shirt to playing the piano—fundamentally involve two components: (1) generating specific patterns of muscle activity (here, termed “synergies”); and (2) stringing these into purposeful sequences. Although transcranial direct current stimulation (tDCS) of the primary motor cortex (M1) has been found to increase the learning of motor sequences, it is unknown whether it can similarly facilitate motor synergy learning. Here, we determined the effects of tDCS on the learning of motor synergies using a novel hand configuration task that required the production of difficult muscular activation patterns. Bihemispheric tDCS was applied to M1 of healthy, right-handed human participants during 4 d of repetitive left-hand configuration training in a double-blind design. tDCS augmented synergy learning, leading subsequently to faster and more synchronized execution. This effect persisted for at least 4 weeks after training. Qualitatively similar tDCS-associated improvements occurred during training of finger sequences in a separate subject cohort. We additionally determined whether tDCS only improved the acquisition of motor memories for specific synergies/sequences or whether it also facilitated more general parts of the motor representations, which could be transferred to novel movements. Critically, we observed that tDCS effects generalized to untrained hand configurations and untrained finger sequences (i.e., were nonspecific), as well as to the untrained hand (i.e., were effector-independent). Hence, bihemispheric tDCS may be a promising adjunct to neurorehabilitative training regimes, in which broad transfer to everyday tasks is highly desirable. PMID:24431461

  2. Opportunities for Synergy Between Natural Gas and Renewable Energy in the Electric Power and Transportation Sectors

    SciTech Connect

    Lee, A.; Zinaman, O.; Logan, J.

    2012-12-01

    Use of both natural gas and renewable energy has grown significantly in recent years. Both forms of energy have been touted as key elements of a transition to a cleaner and more secure energy future, but much of the current discourse considers each in isolation or concentrates on the competitive impacts of one on the other. This paper attempts, instead, to explore potential synergies of natural gas and renewable energy in the U.S. electric power and transportation sectors.

  3. Finger synergies during multi-finger cyclic production of moment of force

    PubMed Central

    Zhang, Wei; Zatsiorsky, Vladimir M.

    2010-01-01

    We investigated multi-finger synergies stabilizing the total moment of force and the total force when the subjects produced a quick cyclic change in the total moment of force. The seated subjects performed the task with the fingers of the dominant arm while paced by the metronome at 1.33 Hz. They were required to produce a rhythmic, sine-like change in the total pronation–supination moment of force computed with respect to the midpoint between the middle and ring fingers. The framework of the uncontrolled manifold hypothesis was used to compute indices of stabilization of the total moment and of the total force across 20 cycles. Variance of the total moment showed a cyclic pattern with peaks close to the peak rate of the moment change. Variance of the total force was maximal close to peak moment into supination. Higher magnitudes of the moment directed against the required moment direction (antagonist moment) were produced by individual fingers during supination efforts as compared to pronation efforts. Indices of multi-finger synergies showed across-trials stabilization of the total moment over the whole cycle but not of the total force. These indices were smaller during supination efforts. We conclude that the central nervous system facilitates multi-finger synergies stabilizing the total rotational action across a variety of tasks. Synergies stabilizing the total force are not seen in tasks that do not explicitly require accurate force control. Pronation efforts are performed more efficiently and with better stabilization of the action. PMID:16944107

  4. Synergy as design principle for metabolic engineering of 1-propanol production in Escherichia coli.

    PubMed

    Shen, Claire R; Liao, James C

    2013-05-01

    Synthesis of a desired product can often be achieved via more than one metabolic pathway. Whether naturally evolved or synthetically engineered, these pathways often exhibit specific properties that are suitable for production under distinct conditions and host organisms. Synergy between pathways arises when the underlying pathway characteristics, such as reducing equivalent demand, ATP requirement, intermediate utilization, and cofactor preferences, are complementary to each other. Utilization of such pathways in combination leads to an increased metabolite productivity and/or yield compared to using each pathway alone. This work illustrates the principle of synergy between two different pathways for 1-propanol production in Escherichia coli. A model-guided design based on maximum theoretical yield calculations identified synergy of the native threonine pathway and the heterologous citramalate pathway in terms of production yield across all flux ratios between the two pathways. Characterization of the individual pathways by host gene deletions demonstrates their distinct metabolic characteristics: the necessity of TCA cycle for threonine pathway and the independence of TCA cycle for the citramalate pathway. The two pathways are also complementary in driving force demands. Production experiments verified the synergistic effects predicted by the yield model, in which the platform with dual pathway for 2-ketobutyrate synthesis achieved higher yield (0.15g/g of glucose) and productivity (0.12g/L/h) of 1-propanol than individual ones alone: the threonine pathway (0.09g/g; 0.04g/L/h) or the citramalate pathway (0.11g/g; 0.04g/L/h). Thus, incorporation of synergy into the design principle of metabolic engineering may improve the production yield and rate of the desired compound. PMID:23376654

  5. Quantifying subpopulation synergy for antibiotic combinations via mechanism-based modeling and a sequential dosing design.

    PubMed

    Landersdorfer, Cornelia B; Ly, Neang S; Xu, Hongmei; Tsuji, Brian T; Bulitta, Jürgen B

    2013-05-01

    Quantitative modeling of combination therapy can describe the effects of each antibiotic against multiple bacterial populations. Our aim was to develop an efficient experimental and modeling strategy that evaluates different synergy mechanisms using a rapidly killing peptide antibiotic (nisin) combined with amikacin or linezolid as probe drugs. Serial viable counts over 48 h were obtained in time-kill experiments with all three antibiotics in monotherapy against a methicillin-resistant Staphylococcus aureus USA300 strain (inoculum, 10(8) CFU/ml). A sequential design (initial dosing of 8 or 32 mg/liter nisin, switched to amikacin or linezolid at 1.5 h) assessed the rate of killing by amikacin and linezolid against nisin-intermediate and nisin-resistant populations. Simultaneous combinations were additionally studied and all viable count profiles comodeled in S-ADAPT and NONMEM. A mechanism-based model with six populations (three for nisin times two for amikacin) yielded unbiased and precise (r = 0.99, slope = 1.00; S-ADAPT) individual fits. The second-order killing rate constants for nisin against the three populations were 5.67, 0.0664, and 0.00691 liter/(mg · h). For amikacin, the maximum killing rate constants were 10.1 h(-1) against its susceptible and 0.771 h(-1) against its less-susceptible populations, with 14.7 mg/liter amikacin causing half-maximal killing. After incorporating the effects of nisin and amikacin against each population, no additional synergy function was needed. Linezolid inhibited successful bacterial replication but did not efficiently kill populations less susceptible to nisin. Nisin plus amikacin achieved subpopulation synergy. The proposed sequential and simultaneous dosing design offers an efficient approach to quantitatively characterize antibiotic synergy over time and prospectively evaluate antibiotic combination dosing strategies. PMID:23478962

  6. Evaluation and modeling of synergy to pheromone and plant kairomone in American palm weevil

    PubMed Central

    2011-01-01

    Background Many behavioral responses to odors are synergistic, particularly in insects. In beetles, synergy often involves a pheromone and a plant odor, and pest management relies on them for the use of combined lures. To investigate olfactory synergy mechanisms, we need to distinguish synergistic effects from additive ones, when all components of the mixture are active. Results As versatile tools and procedures were not available, we developed a bioassay, and a mathematical model to evaluate synergy between aggregation pheromone (P) and host plant odors (kairomone: K) in the American palm weevil, a pest insect showing enhanced responses to P+K mixtures. Responses to synthetic P and natural K were obtained using a 4-arm olfactometer coupled to a controlled volatile delivery system. We showed that: (1) Response thresholds were ca. 10 and 100 pg/s respectively for P and K. (2) Both stimuli induced similar maximum response. (3) Increasing the dose decreased the response for P to the point of repellence and maintained a maximum response for K. (4) P and K were synergistic over a 100-fold range of doses with experimental responses to P+K mixtures greater than the ones predicted assuming additive effects. Responses close to maximum were associated with the mixture amounts below the response threshold for both P and K. Conclusion These results confirm the role of olfactory synergy in optimizing active host-plant localization by phytophagous insects. Our evaluation procedure can be generalized to test synergistic or inhibitory integrated responses of various odor mixtures for various insects. PMID:21463509

  7. Learned parametrized dynamic movement primitives with shared synergies for controlling robotic and musculoskeletal systems

    PubMed Central

    Rückert, Elmar; d'Avella, Andrea

    2013-01-01

    A salient feature of human motor skill learning is the ability to exploit similarities across related tasks. In biological motor control, it has been hypothesized that muscle synergies, coherent activations of groups of muscles, allow for exploiting shared knowledge. Recent studies have shown that a rich set of complex motor skills can be generated by a combination of a small number of muscle synergies. In robotics, dynamic movement primitives are commonly used for motor skill learning. This machine learning approach implements a stable attractor system that facilitates learning and it can be used in high-dimensional continuous spaces. However, it does not allow for reusing shared knowledge, i.e., for each task an individual set of parameters has to be learned. We propose a novel movement primitive representation that employs parametrized basis functions, which combines the benefits of muscle synergies and dynamic movement primitives. For each task a superposition of synergies modulates a stable attractor system. This approach leads to a compact representation of multiple motor skills and at the same time enables efficient learning in high-dimensional continuous systems. The movement representation supports discrete and rhythmic movements and in particular includes the dynamic movement primitive approach as a special case. We demonstrate the feasibility of the movement representation in three multi-task learning simulated scenarios. First, the characteristics of the proposed representation are illustrated in a point-mass task. Second, in complex humanoid walking experiments, multiple walking patterns with different step heights are learned robustly and efficiently. Finally, in a multi-directional reaching task simulated with a musculoskeletal model of the human arm, we show how the proposed movement primitives can be used to learn appropriate muscle excitation patterns and to generalize effectively to new reaching skills. PMID:24146647

  8. Cortical Activation Associated with Muscle Synergies of the Human Male Pelvic Floor

    PubMed Central

    Asavasopon, Skulpan; Rana, Manku; Kirages, Daniel J.; Yani, Moheb S.; Fisher, Beth E.; Hwang, Darryl H.; Lohman, Everett B.; Berk, Lee S.

    2014-01-01

    Human pelvic floor muscles have been shown to operate synergistically with a wide variety of muscles, which has been suggested to be an important contributor to continence and pelvic stability during functional tasks. However, the neural mechanism of pelvic floor muscle synergies remains unknown. Here, we test the hypothesis that activation in motor cortical regions associated with pelvic floor activation are part of the neural substrate for such synergies. We first use electromyographic recordings to extend previous findings and demonstrate that pelvic floor muscles activate synergistically during voluntary activation of gluteal muscles, but not during voluntary activation of finger muscles. We then show, using functional magnetic resonance imaging (fMRI), that a region of the medial wall of the precentral gyrus consistently activates during both voluntary pelvic floor muscle activation and voluntary gluteal activation, but not during voluntary finger activation. We finally confirm, using transcranial magnetic stimulation, that the fMRI-identified medial wall region is likely to generate pelvic floor muscle activation. Thus, muscle synergies of the human male pelvic floor appear to involve activation of motor cortical areas associated with pelvic floor control. PMID:25297107

  9. Constraints imposed by the lower extremity extensor synergy in chronic hemiparetic stroke: Preliminary findings.

    PubMed

    Sanchez, Natalia; Dewald, Julius P A

    2014-01-01

    In the present manuscript we implemented the MultiLEIT, a lower extremity isometric torque measurement device to quantify spontaneous joint torque coupling during maximal torque generation in the paretic leg of in chronic hemiparetic stroke. We quantified extension/adduction coupling (coincident with the clinical extension synergy) during the generation of hip extension and ankle plantarflexion maximum voluntary torques. Subjects were then instructed to generate torques outside the synergy by combining hip extension+ hip abduction or ankle plantarflexion + hip abduction. During the hip dual task, the paretic hip torques were significantly different from those measured in the non-paretic and control leg (F = 22.9719, p = 0) and resulted in the inability to generate torques outside the extensor synergy patters. During the dual ankle/ hip task, the paretic extremity generated significantly smaller hip abduction torques compared to controls and to the non-paretic extremity (F = 15.861, p = 0). During this task the paretic extremity was capable of neutralizing the spontaneous adduction torque and generate a net albeit small abduction torque. Results may indicate an increased descending drive from brain stem pathways, particularly during hip extension, responsible for constraints in generating hip abduction torques after stroke. PMID:25571315

  10. Evaluating synergy between marbofloxacin and gentamicin in Pseudomonas aeruginosa strains isolated from dogs with otitis externa.

    PubMed

    Jerzsele, Ákos; Pásztiné-Gere, Erzsébet

    2015-03-01

    The aim of this study was to determine antimicrobial susceptibility of Pseudomonas aeruginosa strains to marbofloxacin and gentamicin, and investigate the possible synergistic, additive, indifferent or antagonistic effects between the two agents. P. aeruginosa strains can develop resistance quickly against certain antibiotics if used alone, thus the need emerges to find synergistic combinations. A total of 68 P. aeruginosa strains isolated from dogs were examined. In order to describe interactions between marbofloxacin and gentamicin the checkerboard microdilution method was utilized. The MICs (minimum inhibitory concentrations) for marbofloxacin and gentamicin were in the range 0.25-64 mg/L and 0.25-32 mg/L, respectively. The combination of marbofloxacin and gentamicin was more effective with a MIC range of 0.031-8 mg/L and a MIC90 of 1 mg/L, compared to 16 mg/L for marbofloxacin alone and 8 mg/L for gentamicin alone. The FIC (fractional inhibitory concentration) indices ranged from 0.0945 (pronounced synergy) to 1.0625 (indifference). Synergy between marbofloxacin and gentamicin was found in 33 isolates. The mean FIC index is 0.546, which represents a partial synergistic/additive effect close to the full synergy threshold. In vitro results indicate that marbofloxacin and gentamicin as partially synergistic agents may prove clinically useful in combination therapy against P. aeruginosa infections. Although marbofloxacin is not used in the human practice, the interactions between fluoroquinolones and aminoglycosides may have importance outside the veterinary field. PMID:25823453

  11. Antibacterial synergy of curcumin with antibiotics against biofilm producing clinical bacterial isolates

    PubMed Central

    Kali, Arunava; Bhuvaneshwar, Devaraj; Charles, Pravin M. V.; Seetha, Kunigal Srinivasaiah

    2016-01-01

    Introduction: The role of natural bioactive substances in treating infections has been rediscovered as bacterial resistance become common to most of the antibiotics. Curcumin is a bioactive substance from turmeric. Owing to antimicrobial properties, its prospect as an antibacterial agent is currently under focus. Materials and Methods: We have evaluated the in vitro synergy of curcumin with antibiotics against sixty biofilm producing bacterial isolates. Congo red agar method was used to identify the biofilm producing isolates. Curcumin minimum inhibitory concentration (MIC) was determined by agar dilution method. Its antibiotic synergy was identified by the increase in disc diffusion zone size on Mueller-Hinton agar with 32 mg/L curcumin. Results: The mean MICs of curcumin against Gram-positive and Gram-negative isolates were 126.9 mg/L and 117.4 mg/L, respectively. Maximum synergy was observed with ciprofloxacin among Gram-positive and amikacin, gentamicin, and cefepime among Gram-negative isolates. Conclusions: Curcumin per se as well as in combination with other antibiotics has a demonstrable antibacterial action against biofilm producing bacterial isolates. It may have a beneficial role in supplementing antibiotic therapy. PMID:27330262

  12. The Influence of Dopaminergic Striatal Innervation on Upper Limb Locomotor Synergies

    PubMed Central

    Isaias, Ioannis U.; Volkmann, Jens; Marzegan, Alberto; Marotta, Giorgio; Cavallari, Paolo; Pezzoli, Gianni

    2012-01-01

    To determine the role of striatal dopaminergic innervation on upper limb synergies during walking, we measured arm kinematics in 13 subjects with Parkinson disease. Patients were recruited according to several inclusion criteria to represent the best possible in vivo model of dopaminergic denervation. Of relevance, we included only subjects with normal spatio-temporal parameters of the stride and gait speed to avoid an impairment of upper limbs locomotor synergies as a consequence of gait impairment per se. Dopaminergic innervation of the striatum was measured by FP-CIT and SPECT. All patients showed a reduction of gait-associated arms movement. No linear correlation was found between arm ROM reduction and contralateral dopaminergic putaminal innervation loss. Still, a partition analysis revealed a 80% chance of reduced arm ROM when putaminal dopamine content loss was >47%. A significant correlation was described between the asymmetry indices of the swinging of the two arms and dopaminergic striatal innervation. When arm ROM was reduced, we found a positive correlation between upper-lower limb phase shift modulation (at different gait velocities) and striatal dopaminergic innervation. These findings are preliminary evidence that dopaminergic striatal tone plays a modulatory role in upper-limb locomotor synergies and upper-lower limb coupling while walking at different velocities. PMID:23236504

  13. Age-related changes in multifinger synergies in accurate moment of force production tasks

    PubMed Central

    Olafsdottir, Halla; Zhang, Wei; Zatsiorsky, Vladimir M.; Latash, Mark L.

    2010-01-01

    The purpose of this investigation was to document and quantify age-related differences in the coordination of fingers during a task that required production of an accurate time profile of the total moment of force by the four fingers of a hand. We hypothesized that elderly subjects would show a decreased ability to stabilize a time profile of the total moment of force, leading to larger indexes of moment variability compared with young subjects. The subjects followed a trapezoidal template on a computer screen by producing a time profile of the total moment of force while pressing down on force sensors with the four fingers of the right (dominant) hand. To quantify synergies, we used the framework of the uncontrolled manifold hypothesis. The elderly subjects produced larger total force, larger variance of both total force and total moment of force, and larger involvement of fingers that produced moment of force against the required moment direction (antagonist moment). This was particularly prominent during supination efforts. Young subjects showed covariation of commands to fingers across trials that stabilized the moment of total force (moment-stabilizing synergy), while elderly subjects failed to do so. Both subject groups showed similar indexes of covariation of commands to the fingers that stabilized the time profile of the total force. The lack of moment-stabilizing synergies may be causally related to the documented impairment of hand function with age. PMID:17204576

  14. Striking multiple synergies created by combining reduced graphene oxides and carbon nanotubes for polymer nanocomposites

    NASA Astrophysics Data System (ADS)

    Song, Ping'an; Liu, Lina; Fu, Shenyuan; Yu, Youming; Jin, Chunde; Wu, Qiang; Zhang, Yan; Li, Qian

    2013-03-01

    The extraordinary properties of carbon nanotubes (CNTs) and graphene stimulate the development of advanced composites. Recently, several studies have reported significant synergies in the mechanical, electrical and thermal conductivity properties of polymer nanocomposites by incorporating their nanohybrids. In this work, we created polypropylene nanocomposites with homogeneous dispersion of CNTs and reduced graphene oxides via a facile polymer-latex-coating plus melt-mixing strategy, and investigated their synergistic effects in their viscoelastic, gas barrier, and flammability properties. Interestingly, the results show remarkable synergies, enhancing their melt modulus and viscosity, O2 barrier, and flame retardancy properties and respectively exhibiting a synergy percentage of 15.9%, 45.3%, and 20.3%. As previously reported, we also observed remarkable synergistic effects in their tensile strength (14.3%) and Young’s modulus (27.1%), electrical conductivity (32.3%) and thermal conductivity (34.6%). These impressive results clearly point towards a new strategy to create advanced materials by adding binary combinations of different types of nanofillers.

  15. Molecular Signatures of Nicotinoid-Pathogen Synergy in the Termite Gut

    PubMed Central

    Sen, Ruchira; Raychoudhury, Rhitoban; Cai, Yunpeng; Sun, Yijun; Lietze, Verena-Ulrike; Peterson, Brittany F.; Scharf, Michael E.; Boucias, Drion G.

    2015-01-01

    Previous studies in lower termites revealed unexpected synergies between nicotinoid insecticides and fungal entomopathogens. The present study investigated molecular mechanisms of nicotinoid-pathogen synergy in the lower termite Reticulitermes flavipes, using the nicotinoid, imidacloprid, in combination with fungal and bacterial entomopathogens. Particular focus was placed on metatranscriptome composition and microbial dynamics in the symbiont-rich termite gut, which houses diverse mixes of protists and bacteria. cDNA microarrays containing a mix of host and protist symbiont oligonucleotides were used to simultaneously assess termite and protist gene expression. Five treatments were compared that included single challenges with sublethal doses of fungi (Metharizium anisopliae), bacteria (Serratia marcescens) or imidacloprid, and dual challenges with fungi + imidacloprid or bacteria + imidacloprid. Our findings point towards protist dysbiosis and compromised social behavior, rather than suppression of stereotypical immune defense mechanisms, as the dominant factors underlying nicotinoid-pathogen synergy in termites. Also, greater impacts observed for the fungal pathogen than for the bacterial pathogen suggest that the rich bacterial symbiont community in the R. flavipes gut (>5000 species-level phylotypes) exists in an ecological balance that effectively excludes exogenous bacterial pathogens. These findings significantly advance our understanding of antimicrobial defenses in this important eusocial insect group, as well as provide novel insights into how nicotinoids can exert deleterious effects on social insect colonies. PMID:25837376

  16. A synergy-based hand control is encoded in human motor cortical areas

    PubMed Central

    Leo, Andrea; Handjaras, Giacomo; Bianchi, Matteo; Marino, Hamal; Gabiccini, Marco; Guidi, Andrea; Scilingo, Enzo Pasquale; Pietrini, Pietro; Bicchi, Antonio; Santello, Marco; Ricciardi, Emiliano

    2016-01-01

    How the human brain controls hand movements to carry out different tasks is still debated. The concept of synergy has been proposed to indicate functional modules that may simplify the control of hand postures by simultaneously recruiting sets of muscles and joints. However, whether and to what extent synergic hand postures are encoded as such at a cortical level remains unknown. Here, we combined kinematic, electromyography, and brain activity measures obtained by functional magnetic resonance imaging while subjects performed a variety of movements towards virtual objects. Hand postural information, encoded through kinematic synergies, were represented in cortical areas devoted to hand motor control and successfully discriminated individual grasping movements, significantly outperforming alternative somatotopic or muscle-based models. Importantly, hand postural synergies were predicted by neural activation patterns within primary motor cortex. These findings support a novel cortical organization for hand movement control and open potential applications for brain-computer interfaces and neuroprostheses. DOI: http://dx.doi.org/10.7554/eLife.13420.001 PMID:26880543

  17. Synergy in Extraction System Chemistry: Combining Configurational Entropy, Film Bending, and Perturbation of Complexation.

    PubMed

    Rey, J; Dourdain, S; Berthon, L; Jestin, J; Pellet-Rostaing, S; Zemb, T

    2015-06-30

    Iron-uranium selectivity in liquid-liquid extraction depends not only on the mole fraction of extractants, but also on the nature of the diluent used, even if the diluent has no complexation interaction with the extracted ions. Modeling strong nonlinearity is difficult to parametrize without a large number of parameters, interpreted as "apparent constants". We determine in this paper the synergy curve versus mole fraction of HDEHP-TOPO (di(2-ethylexyl) phosphoric acid/tri-n-octyl phosphine oxide) and compare the free energy of aggregation to the free energy of extraction in various diluents. There is always a concomitant maximum of the two quantities, but with a gradual influence on intensity. The diluent is wetting the chains of the reverse aggregates responsible of the extraction. We show here that the intensity of the unexplained synergy peak is strongly dependent on the "penetrating" or "nonpenetrating" nature of the diluent. This experimental determination allows us to attribute the synergy to a combination of entropic effects favoring extraction, opposed to perturbation of the first coordination sphere by penetration as well as surfactant film bending energy. PMID:26053416

  18. Striking multiple synergies created by combining reduced graphene oxides and carbon nanotubes for polymer nanocomposites.

    PubMed

    Song, Ping'an; Liu, Lina; Fu, Shenyuan; Yu, Youming; Jin, Chunde; Wu, Qiang; Zhang, Yan; Li, Qian

    2013-03-29

    The extraordinary properties of carbon nanotubes (CNTs) and graphene stimulate the development of advanced composites. Recently, several studies have reported significant synergies in the mechanical, electrical and thermal conductivity properties of polymer nanocomposites by incorporating their nanohybrids. In this work, we created polypropylene nanocomposites with homogeneous dispersion of CNTs and reduced graphene oxides via a facile polymer-latex-coating plus melt-mixing strategy, and investigated their synergistic effects in their viscoelastic, gas barrier, and flammability properties. Interestingly, the results show remarkable synergies, enhancing their melt modulus and viscosity, O2 barrier, and flame retardancy properties and respectively exhibiting a synergy percentage of 15.9%, 45.3%, and 20.3%. As previously reported, we also observed remarkable synergistic effects in their tensile strength (14.3%) and Young's modulus (27.1%), electrical conductivity (32.3%) and thermal conductivity (34.6%). These impressive results clearly point towards a new strategy to create advanced materials by adding binary combinations of different types of nanofillers. PMID:23459335

  19. Construction of synergy networks from gene expression data related to disease.

    PubMed

    Chatterjee, Prantik; Pal, Nikhil Ranjan

    2016-09-30

    A few methods have been developed to determine whether genes collaborate with each other in relation to a particular disease using an information theoretic measure of synergy. Here, we propose an alternative definition of synergy and justify that our definition improves upon the existing measures of synergy in the context of gene interactions. We use this definition on a prostate cancer data set consisting of gene expression levels in both cancerous and non-cancerous samples and identify pairs of genes which are unable to discriminate between cancerous and non-cancerous samples individually but can do so jointly when we take their synergistic property into account. We also propose a very simple yet effective technique for computation of conditional entropy at a very low cost. The worst case complexity of our method is O(n) while the best case complexity of a state-of-the-art method is O(n(2)). Furthermore, our method can also be extended to find synergistic relation among triplets or even among a larger number of genes. Finally, we validate our results by demonstrating that these findings cannot be due to pure chance and provide the relevance of the synergistic pairs in cancer biology. PMID:27222483

  20. Synergy-directed fractionation of botanical medicines: a case study with goldenseal (Hydrastis canadensis).

    PubMed

    Junio, Hiyas A; Sy-Cordero, Arlene A; Ettefagh, Keivan A; Burns, Johnna T; Micko, Kathryn T; Graf, Tyler N; Richter, Scott J; Cannon, Robert E; Oberlies, Nicholas H; Cech, Nadja B

    2011-07-22

    It is often argued that the efficacy of herbal medicines is a result of the combined action of multiple constituents that work synergistically or additively. Determining the bioactive constituents in these mixtures poses a significant challenge. We have developed an approach to address this challenge, synergy-directed fractionation, which combines comprehensive mass spectrometry profiling with synergy assays and natural products isolation. The applicability of synergy-directed fractionation was demonstrated using the botanical medicine goldenseal (Hydrastis canadensis) as a case study. Three synergists from goldenseal were identified, sideroxylin, 8-desmethyl-sideroxylin, and 6-desmethyl-sideroxylin. These flavonoids synergistically enhance the antimicrobial activity of the alkaloid berberine (also a constituent of H. canadensis) against Staphylococcus aureus by inhibition of the NorA multidrug resistance pump. The flavonoids possess no inherent antimicrobial activity against S. aureus; therefore, they could have been missed using traditional bioactivity-directed fractionation. The flavonoid synergists are present at higher concentration in extracts from H. canadensis leaves, while the antimicrobial alkaloid berberine is present at higher levels in H. canadensis roots. Thus, it may be possible to produce an extract with optimal activity against S. aureus using a combination of goldenseal roots and leaves. PMID:21661731

  1. Postural Control during Upper Body Locomotor-Like Movements: Similar Synergies Based on Dissimilar Muscle Modes

    PubMed Central

    Danna-Dos-Santos, Alessander; Shapkova, Elena Yu.; Shapkova, Alexandra L.; Degani, Adriana M.; Latash, Mark L.

    2009-01-01

    We studied the organization of leg and trunk muscles into groups (M-modes) and co-variation of M-mode involvement (M-mode synergies) during whole-body tasks associated with large variations of the moment of force about the vertical body axis. Our major questions were: (1) Can muscle activation patterns during such tasks be described with a few M-modes common across tasks and subjects? (2) Do these modes form the basis for synergies stabilizing MZ time pattern? (3) Will this organization differ between an explicit body rotation task and a task associated with locomotor-like alternating arm movements? Healthy subjects stood barefoot on the force platform and performed two motor tasks while paced by the metronome at 0.7, 1.0, and 1.4 Hz: Cyclic rotation of the upper body about the vertical body axis (body rotation task), and alternating rhythmic arm movements imitating those during running or quick walking (arm movement task). Principal component analysis was used to identify three M-modes within the space of integrated indices of muscle activity. The M-mode vectors showed clustering neither across subjects nor across frequencies. Variance in the M-mode space across sway cycles was partitioned into two components, one that did not affect the average value of MZ shift ("good variance") and the other that did. An index was computed reflecting the relative amount of the "good variance"; positive values of this index have been interpreted as reflecting a multi-M-mode synergy stabilizing the MZ trajectory. On average, the index was positive for both tasks and across all frequencies studied. However, the magnitude of the index was smaller for the intermediate frequency (1 Hz). The results show that the organization of muscles into groups during relatively complex whole-body tasks can differ significantly across both task variations and subjects. Nevertheless, the central nervous system seems to be able to build MZ stabilizing synergies based on different sets of M

  2. Hybrid mimics and hybrid vigor in Arabidopsis

    PubMed Central

    Wang, Li; Greaves, Ian K.; Groszmann, Michael; Wu, Li Min; Dennis, Elizabeth S.; Peacock, W. James

    2015-01-01

    F1 hybrids can outperform their parents in yield and vegetative biomass, features of hybrid vigor that form the basis of the hybrid seed industry. The yield advantage of the F1 is lost in the F2 and subsequent generations. In Arabidopsis, from F2 plants that have a F1-like phenotype, we have by recurrent selection produced pure breeding F5/F6 lines, hybrid mimics, in which the characteristics of the F1 hybrid are stabilized. These hybrid mimic lines, like the F1 hybrid, have larger leaves than the parent plant, and the leaves have increased photosynthetic cell numbers, and in some lines, increased size of cells, suggesting an increased supply of photosynthate. A comparison of the differentially expressed genes in the F1 hybrid with those of eight hybrid mimic lines identified metabolic pathways altered in both; these pathways include down-regulation of defense response pathways and altered abiotic response pathways. F6 hybrid mimic lines are mostly homozygous at each locus in the genome and yet retain the large F1-like phenotype. Many alleles in the F6 plants, when they are homozygous, have expression levels different to the level in the parent. We consider this altered expression to be a consequence of transregulation of genes from one parent by genes from the other parent. Transregulation could also arise from epigenetic modifications in the F1. The pure breeding hybrid mimics have been valuable in probing the mechanisms of hybrid vigor and may also prove to be useful hybrid vigor equivalents in agriculture. PMID:26283378

  3. Hybrid supercapacitor-battery materials for fast electrochemical charge storage

    NASA Astrophysics Data System (ADS)

    Vlad, A.; Singh, N.; Rolland, J.; Melinte, S.; Ajayan, P. M.; Gohy, J.-F.

    2014-03-01

    High energy and high power electrochemical energy storage devices rely on different fundamental working principles - bulk vs. surface ion diffusion and electron conduction. Meeting both characteristics within a single or a pair of materials has been under intense investigations yet, severely hindered by intrinsic materials limitations. Here, we provide a solution to this issue and present an approach to design high energy and high power battery electrodes by hybridizing a nitroxide-polymer redox supercapacitor (PTMA) with a Li-ion battery material (LiFePO4). The PTMA constituent dominates the hybrid battery charge process and postpones the LiFePO4 voltage rise by virtue of its ultra-fast electrochemical response and higher working potential. We detail on a unique sequential charging mechanism in the hybrid electrode: PTMA undergoes oxidation to form high-potential redox species, which subsequently relax and charge the LiFePO4 by an internal charge transfer process. A rate capability equivalent to full battery recharge in less than 5 minutes is demonstrated. As a result of hybrid's components synergy, enhanced power and energy density as well as superior cycling stability are obtained, otherwise difficult to achieve from separate constituents.

  4. Hybrid supercapacitor-battery materials for fast electrochemical charge storage

    PubMed Central

    Vlad, A.; Singh, N.; Rolland, J.; Melinte, S.; Ajayan, P. M.; Gohy, J.-F.

    2014-01-01

    High energy and high power electrochemical energy storage devices rely on different fundamental working principles - bulk vs. surface ion diffusion and electron conduction. Meeting both characteristics within a single or a pair of materials has been under intense investigations yet, severely hindered by intrinsic materials limitations. Here, we provide a solution to this issue and present an approach to design high energy and high power battery electrodes by hybridizing a nitroxide-polymer redox supercapacitor (PTMA) with a Li-ion battery material (LiFePO4). The PTMA constituent dominates the hybrid battery charge process and postpones the LiFePO4 voltage rise by virtue of its ultra-fast electrochemical response and higher working potential. We detail on a unique sequential charging mechanism in the hybrid electrode: PTMA undergoes oxidation to form high-potential redox species, which subsequently relax and charge the LiFePO4 by an internal charge transfer process. A rate capability equivalent to full battery recharge in less than 5 minutes is demonstrated. As a result of hybrid's components synergy, enhanced power and energy density as well as superior cycling stability are obtained, otherwise difficult to achieve from separate constituents. PMID:24603843

  5. Hybrid supercapacitor-battery materials for fast electrochemical charge storage.

    PubMed

    Vlad, A; Singh, N; Rolland, J; Melinte, S; Ajayan, P M; Gohy, J-F

    2014-01-01

    High energy and high power electrochemical energy storage devices rely on different fundamental working principles--bulk vs. surface ion diffusion and electron conduction. Meeting both characteristics within a single or a pair of materials has been under intense investigations yet, severely hindered by intrinsic materials limitations. Here, we provide a solution to this issue and present an approach to design high energy and high power battery electrodes by hybridizing a nitroxide-polymer redox supercapacitor (PTMA) with a Li-ion battery material (LiFePO4). The PTMA constituent dominates the hybrid battery charge process and postpones the LiFePO4 voltage rise by virtue of its ultra-fast electrochemical response and higher working potential. We detail on a unique sequential charging mechanism in the hybrid electrode: PTMA undergoes oxidation to form high-potential redox species, which subsequently relax and charge the LiFePO4 by an internal charge transfer process. A rate capability equivalent to full battery recharge in less than 5 minutes is demonstrated. As a result of hybrid's components synergy, enhanced power and energy density as well as superior cycling stability are obtained, otherwise difficult to achieve from separate constituents. PMID:24603843

  6. Synergy of β-Lactams with Vancomycin against Methicillin-Resistant Staphylococcus aureus: Correlation of Disk Diffusion and Checkerboard Methods.

    PubMed

    Sy, Cheng Len; Huang, Tsi-Shu; Chen, Chii Shiang; Chen, Yao-Shen; Tsai, Hung-Chin; Wann, Shue-Renn; Wu, Kuan-Sheng; Chen, Jui-Kuang; Lee, Susan Shin-Jung; Liu, Yung-Ching

    2016-03-01

    Modified disk diffusion (MDD) and checkerboard tests were employed to assess the synergy of combinations of vancomycin and β-lactam antibiotics for 59 clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and Mu50 (ATCC 700699). Bacterial inocula equivalent to 0.5 and 2.0 McFarland standard were inoculated on agar plates containing 0, 0.5, 1, and 2 μg/ml of vancomycin. Oxacillin-, cefazolin-, and cefoxitin-impregnated disks were applied to the surface, and the zones of inhibition were measured at 24 h. The CLSI-recommended checkerboard method was used as a reference to detect synergy. The MICs for vancomycin were determined using the Etest method, broth microdilution, and the Vitek 2 automated system. Synergy was observed with the checkerboard method in 51% to 60% of the isolates when vancomycin was combined with any β-lactam. The fractional inhibitory concentration indices were significantly lower in MRSA isolates with higher vancomycin MIC combinations (P < 0.05). The overall agreement between the MDD and checkerboard methods to detect synergy in MRSA isolates with bacterial inocula equivalent to McFarland standard 0.5 were 33.0% and 62.5% for oxacillin, 45.1% and 52.4% for cefazolin, and 43.1% and 52.4% for cefoxitin when combined with 0.5 and 2 μg/ml of vancomycin, respectively. Based on our study, the simple MDD method is not recommended as a replacement for the checkerboard method to detect synergy. However, it may serve as an initial screening method for the detection of potential synergy when it is not feasible to perform other labor-intensive synergy tests. PMID:26677253

  7. Integration of robotics and neuroscience beyond the hand: What kind of synergies?. Comment on "Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands" by Marco Santello et al.

    NASA Astrophysics Data System (ADS)

    d'Avella, Andrea

    2016-07-01

    Santello et al. [1] review an impressive amount of work on the control of biological and artificial hands that demonstrates how the concept of synergies can lead to a successful integration of robotics and neuroscience. Is it possible to generalize the same approach to the control of biological and artificial limbs and bodies beyond the hand? The human hand synergies that appear most relevant for robotic hands are those defined at the kinematic level, i.e. postural synergies [2]. Postural synergies capture the geometric relations among the many joints of the hand and allow for a low dimensional characterization and synthesis of the static hand postures involved in grasping and manipulating a large set of objects. However, many other complex motor skills such as walking, reaching, throwing, and catching require controlling multi-articular time-varying trajectories rather than static postures. Dynamic control of biological and artificial limbs and bodies, especially when geometric and inertial parameters are uncertain and the joints are compliant, poses great challenges. What kind of synergies might simplify the dynamic control of motor skills involving upper and lower limbs as well as the whole body?

  8. How well do the muscular synergies extracted via non-negative matrix factorisation explain the variation of torque at shoulder joint?

    PubMed

    Moghadam, M Nassajian; Aminian, K; Asghari, M; Parnianpour, M

    2013-01-01

    The way central nervous system manages the excess degrees of freedom to solve kinetic redundancy of musculoskeletal system remains an open question. In this study, we utilise the concept of synergy formation as a simplifying control strategy to find the muscle recruitment based on summation of identified muscle synergies to balance the biomechanical demands (biaxial external torque) during an isometric shoulder task. A numerical optimisation-based shoulder model was used to obtain muscle activation levels when a biaxial external isometric torque is imposed at the shoulder glenohumeral joint. In the numerical simulations, 12 different shoulder torque vectors in the transverse plane are considered. For each selected direction for the torque vector, the resulting muscle activation data are calculated. The predicted muscle activation data are used for grouping muscles in some fixed element synergies by the non-negative matrix factorisation method. Next, torque produced by these synergies are computed and projected in the 2D torque space to investigate the magnitude and direction of torques that each muscle synergy generated. The results confirmed our expectation that few dominant synergies are sufficient to reconstruct the torque vectors and each muscle contributed to more than one synergy. Decomposition of the concatenated data, combining the activation and external torque, provided functional muscle synergies that produced torques in the four principal directions. Four muscle synergies were able to account for more than 95% of variation of the original data. PMID:21970618

  9. Trade-Off and Synergy among Ecosystem Services in the Guanzhong-Tianshui Economic Region of China.

    PubMed

    Qin, Keyu; Li, Jing; Yang, Xiaonan

    2015-11-01

    Natural ecosystems provide society with important goods and services. With rapidly increasing populations and excessive utilization of natural resources, humans have been enhancing the production of some services at the expense of others. Although the need for certain trade-offs between conservation and development is urgent, having only a small number of efficient methods to assess such trade-offs has impeded progress. This study focuses on the evaluation of ecosystem services under different land use schemes. It reveals the spatial and temporal distributions of and changes in ecosystem services. Based on a correlation rate model and distribution mapping, the trade-offs and synergies of these ecosystem services can be found. Here, we also describe a new simple approach to quantify the relationships of every trade-off and synergy. The results show that all ecosystem services possess trade-offs and synergies in the study area. The trend of improving carbon sequestration and water interception indicate that these key ecosystem services have the strongest synergy. And the decrease in regional agricultural production and other services, except water yield, may be considered as trade-offs. The synergy between water yield and agricultural production was the most significant, while the trade-off between water interception and carbon sequestration was the most apparent, according to our interaction quantification model. The results of this study have implications for planning and monitoring the future management of natural capital and ecosystem services, and can be integrated into land use decision-making. PMID:26540068

  10. Trade-Off and Synergy among Ecosystem Services in the Guanzhong-Tianshui Economic Region of China

    PubMed Central

    Qin, Keyu; Li, Jing; Yang, Xiaonan

    2015-01-01

    Natural ecosystems provide society with important goods and services. With rapidly increasing populations and excessive utilization of natural resources, humans have been enhancing the production of some services at the expense of others. Although the need for certain trade-offs between conservation and development is urgent, having only a small number of efficient methods to assess such trade-offs has impeded progress. This study focuses on the evaluation of ecosystem services under different land use schemes. It reveals the spatial and temporal distributions of and changes in ecosystem services. Based on a correlation rate model and distribution mapping, the trade-offs and synergies of these ecosystem services can be found. Here, we also describe a new simple approach to quantify the relationships of every trade-off and synergy. The results show that all ecosystem services possess trade-offs and synergies in the study area. The trend of improving carbon sequestration and water interception indicate that these key ecosystem services have the strongest synergy. And the decrease in regional agricultural production and other services, except water yield, may be considered as trade-offs. The synergy between water yield and agricultural production was the most significant, while the trade-off between water interception and carbon sequestration was the most apparent, according to our interaction quantification model. The results of this study have implications for planning and monitoring the future management of natural capital and ecosystem services, and can be integrated into land use decision-making. PMID:26540068

  11. Analysis of Hand and Wrist Postural Synergies in Tolerance Grasping of Various Objects.

    PubMed

    Liu, Yuan; Jiang, Li; Yang, Dapeng; Liu, Hong

    2016-01-01

    Human can successfully grasp various objects in different acceptable relative positions between human hand and objects. This grasp functionality can be described as the grasp tolerance of human hand, which is a significant functionality of human grasp. To understand the motor control of human hand completely, an analysis of hand and wrist postural synergies in tolerance grasping of various objects is needed. Ten healthy right-handed subjects were asked to perform the tolerance grasping with right hand using 6 objects of different shapes, sizes and relative positions between human hand and objects. Subjects were wearing CyberGlove attaching motion tracker on right hand, allowing a measurement of the hand and wrist postures. Correlation analysis of joints and inter-joint/inter-finger modules were carried on to explore the coordination between joints or modules. As the correlation between hand and wrist module is not obvious in tolerance grasping, individual analysis of wrist synergies would be more practical. In this case, postural synergies of hand and wrist were then presented separately through principal component analysis (PCA), expressed through the principal component (PC) information transmitted ratio, PC elements distribution and reconstructed angle error of joints. Results on correlation comparison of different module movements can be well explained by the influence factors of the joint movement correlation. Moreover, correlation analysis of joints and modules showed the wrist module had the lowest correlation among all inter-finger and inter-joint modules. Hand and wrist postures were both sufficient to be described by a few principal components. In terms of the PC elements distribution of hand postures, compared with previous investigations, there was a greater proportion of movement in the thumb joints especially the interphalangeal (IP) and opposition rotation (ROT) joint. The research could serve to a complete understanding of hand grasp, and the design

  12. Synergy of inelastic and elastic energy loss. Temperature effects and electronic stopping power dependence

    DOE PAGESBeta

    Zarkadoula, Eva; Xue, Haizhou; Zhang, Yanwen; Weber, William J.

    2015-06-16

    A combination of an inelastic thermal spike model suitable for insulators and molecular dynamics simulations is used to study the effects of temperature and electronic energy loss on ion track formation, size and morphology in SrTiO3 systems with pre-existing disorder. We find temperature dependence of the ion track size. In addition, we find a threshold in the electronic energy loss for a given pre-existing defect concentration, which indicates a threshold in the synergy between the inelastic and elastic energy loss.

  13. The effect of arm weight support on upper limb muscle synergies during reaching movements

    PubMed Central

    2014-01-01

    Background Compensating for the effect of gravity by providing arm-weight support (WS) is a technique often utilized in the rehabilitation of patients with neurological conditions such as stroke to facilitate the performance of arm movements during therapy. Although it has been shown that, in healthy subjects as well as in stroke survivors, the use of arm WS during the performance of reaching movements leads to a general reduction, as expected, in the level of activation of upper limb muscles, the effects of different levels of WS on the characteristics of the kinematics of motion and of the activity of upper limb muscles have not been thoroughly investigated before. Methods In this study, we systematically assessed the characteristics of the kinematics of motion and of the activity of 14 upper limb muscles in a group of 9 healthy subjects who performed 3-D arm reaching movements while provided with different levels of arm WS. We studied the hand trajectory and the trunk, shoulder, and elbow joint angular displacement trajectories for different levels of arm WS. Besides, we analyzed the amplitude of the surface electromyographic (EMG) data collected from upper limb muscles and investigated patterns of coordination via the analysis of muscle synergies. Results The characteristics of the kinematics of motion varied across WS conditions but did not show distinct trends with the level of arm WS. The level of activation of upper limb muscles generally decreased, as expected, with the increase in arm WS. The same eight muscle synergies were identified in all WS conditions. Their level of activation depended on the provided level of arm WS. Conclusions The analysis of muscle synergies allowed us to identify a modular organization underlying the generation of arm reaching movements that appears to be invariant to the level of arm WS. The results of this study provide a normative dataset for the assessment of the effects of the level of arm WS on muscle synergies in stroke

  14. Impaired grip-lift synergy in children with unilateral brain lesions.

    PubMed

    Forssberg, H; Eliasson, A C; Redon-Zouitenn, C; Mercuri, E; Dubowitz, L

    1999-06-01

    Children with spastic hemiplegia have impaired dexterity in the affected extremity. The purpose of the present study was to investigate whether the force co-ordination pattern during precision grip in 13 children between 4 and 10 years of age with predominant unilateral brain lesions is related to manual dexterity and to the location and size of the brain lesion. The force co-ordination pattern was investigated by means of a specially designed object that monitored the isometric fingertip forces applied to the contact surfaces during precision grip. Hand function was measured by means of neurological examination, functional hand-grips and dexterity. Brain lesions were identified by series of ultrasound and MRI scans. Normally, the fingertip forces are applied to the object in the initial phase of the lift in an invariant force co-ordination pattern (i.e. grip-lift synergy), in which the grip and load forces are initiated simultaneously and increase in parallel with unimodal force rate trajectories. A majority of children with unilateral brain lesions had not developed the force co-ordination pattern typical for their age, but produced an immature or a pathological pattern. The developmental level of the grip-lift synergy was determined and quantified according to criteria derived from earlier studies on normally developed children. There was a clear relationship between the developmental level of the grip-lift synergy and impaired dexterity, indicating that proper development of the force co-ordination pattern is important for skilled hand function. The grip-lift synergy correlated with the total extent of lesions in the contralateral cortex and white matter and with lesions in the thalamus/basal ganglia, while no correlation was found for isolated cortical lesions. The results suggest that the neural circuits involved in the control of the precision grip are organized in a parallel and distributed system in the hemispheres, and that the basal ganglia are important

  15. Drivers and synergies in the management of inland fisheries: Searching for sustainable solutions

    USGS Publications Warehouse

    Lynch, Abigail; Beard, Douglas

    2015-01-01

    At the 2015 Global Conference on Inland Fisheries, we convened a Drivers and Synergies panel and working group to discuss competing sectors (e.g., hydropower, transportation, agriculture, mining and oil and gas extraction, forestry, tourism and recreation, and aquaculture) and large-scale drivers which exist predominately outside of the water sectors (e.g., economic growth, diversifying economies, population growth, urbanization, and climate change).  Drivers will influence these sectors and tradeoffs will be made.  Management of sustainable inland water systems requires making informed choices emphasizing those services that will provide sustainable benefits for humans while maintaining well-functioning ecological systems.  

  16. The SKA and its pathfinders in the next decade: synergies with the TMT

    NASA Astrophysics Data System (ADS)

    Spekkens, Kristine

    2014-07-01

    The next decade will be extremely exciting for centimeter- and meter-wave radio astronomy. Large new facilities such as ASKAP, LOFAR and MeerKAT, as well as major retrofits to existing facilities such as the JVLA and WSRT, are under construction or have begun operations. While revolutionary in and of themselves, these facilities are also important pathfinders to the SKA, whose construction will begin towards the end of this decade. This talk will review the key science that will be delivered by the SKA pathfinders as well as that anticipated with SKA Phase One (2018-2023) and Phase Two (>2023), with a focus on potential synergies with the TMT.

  17. Etest synergy testing of clinical isolates of Staphylococcus aureus demonstrating heterogeneous resistance to vancomycin.

    PubMed

    Tsuji, Brian T; Rybak, Michael J

    2006-01-01

    In search for potential synergistic antimicrobial combinations against Staphylococcus aureus isolates, which display heterogeneous resistance to vancomycin, we evaluated the activities of 21 various combinations involving ampicillin/sulbactam, daptomycin, gentamicin, linezolid, quinupristin/dalfopristin, rifampin, and vancomycin by Etest and time-kill methods. A number of combinations demonstrated either synergistic or additive effects against hGISA SA118 and GISA SA179. Agreement between the Etest and time-kill methods for detecting antimicrobial synergy ranged from 66.6% to 71.4%. The Etest method appears promising, and further investigations are warranted. PMID:16368477

  18. Proton Beam Fast Ignition Fusion: Synergy of Weibel and Rayleigh-Taylor Instabilities

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2011-04-01

    The proton beam generation and focusing in fast ignition inertial confinement fusion is studied. The spatial and energy spread of the proton beam generated in a laser-solid interaction is increased due to the synergy of Weibel and Rayleigh-Taylor instabilities. The focal spot radius can reach 100 μm, which is nearly an order of magnitude larger than the optimal value. The energy spread decreases the beam deposition energy in the focal spot. Under these conditions, ignition of a precompressed DT fuel is achieved with the beam powers much higher than the values presently in consideration. Work supported in part by NIKOLA TESLA Laboratories (Stefan University), La Jolla, CA.

  19. Synergy of inelastic and elastic energy loss. Temperature effects and electronic stopping power dependence

    SciTech Connect

    Zarkadoula, Eva; Xue, Haizhou; Zhang, Yanwen; Weber, William J.

    2015-06-16

    A combination of an inelastic thermal spike model suitable for insulators and molecular dynamics simulations is used to study the effects of temperature and electronic energy loss on ion track formation, size and morphology in SrTiO3 systems with pre-existing disorder. We find temperature dependence of the ion track size. In addition, we find a threshold in the electronic energy loss for a given pre-existing defect concentration, which indicates a threshold in the synergy between the inelastic and elastic energy loss.

  20. Water Extent Monitoring Exploiting MR and HR Remote Sensing Data: Synergy, Constraints and Limits

    NASA Astrophysics Data System (ADS)

    Huber, C.; Uribe, C.; Lai, X.; Huang, S.; Yesou, H.

    2013-01-01

    EO MR and HR imagery, particularly SAR data, are powerful tools to monitor water extent that allow to understand the mechanism of complex key ecosystems such as Poyang Lake, considered as a key element for flood natural control and reduction as well as major resources within the Yangtze middle basin. To assess and validate a such long monitoring (2000 to 2011 with an image every 10 days), a particular attention was paid on data quality : the assessment of water extent synergy derived from multi-resolution dataset, and the impact of meteorological conditions, wind (inducing an increasing of surface roughness) and rain, on the SAR signal quality with bands C and X.

  1. Robots, multi-user virtual environments and healthcare: synergies for future directions.

    PubMed

    Moon, Ajung; Grajales, Francisco J; Van der Loos, H F Machiel

    2011-01-01

    The adoption of technology in healthcare over the last twenty years has steadily increased, particularly as it relates to medical robotics and Multi-User Virtual Environments (MUVEs) such as Second Life. Both disciplines have been shown to improve the quality of care and have evolved, for the most part, in isolation from each other. In this paper, we present four synergies between medical robotics and MUVEs that have the potential to decrease resource utilization and improve the quality of healthcare delivery. We conclude with some foreseeable barriers and future research directions for researchers in these fields. PMID:21335746

  2. Dramatic solvent effect on the synergy between α-tocopherol and BHT antioxidants.

    PubMed

    Marteau, Clémentine; Favier, Dominique; Nardello-Rataj, Véronique; Aubry, Jean-Marie

    2014-10-01

    During the DPPH scavenging assay carried out in non polar and non protic solvents, such as toluene, BHT regenerates α-tocopherol from tocopheryl radical, whereas in polar and protic solvents, like methanol, no regeneration is observed due to a fast electron transfer reaction from the tocopheryl radical to the reactive DPPH radical. Surprisingly, in the presence of a small amount of alcohol, the synergy is exalted and BHT regenerates twice as much α-tocopherol due to a nucleophilic addition of short alcohols on the BHT oxidation product, giving a new phenolic co-antioxidant. PMID:24799226

  3. Hybrid rocket propulsion

    NASA Technical Reports Server (NTRS)

    Holzman, Allen L.

    1993-01-01

    Topics addressed are: (1) comparison of the theoretical impulses; (2) comparison of the density-specific impulses; (3) general propulsion system features comparison; (4) hybrid systems, booster applications; and (5) hybrid systems, upper stage propulsion applications.

  4. Hybridization and hybrid speciation under global change.

    PubMed

    Vallejo-Marín, Mario; Hiscock, Simon J

    2016-09-01

    Contents 1170 I. 1170 II. 1172 III. 1175 IV. 1180 V. 1183 1184 References 1184 SUMMARY: An unintended consequence of global change is an increase in opportunities for hybridization among previously isolated lineages. Here we illustrate how global change can facilitate the breakdown of reproductive barriers and the formation of hybrids, drawing on the flora of the British Isles for insight. Although global change may ameliorate some of the barriers preventing hybrid establishment, for example by providing new ecological niches for hybrids, it will have limited effects on environment-independent post-zygotic barriers. For example, genic incompatibilities and differences in chromosome numbers and structure within hybrid genomes are unlikely to be affected by global change. We thus speculate that global change will have a larger effect on eroding pre-zygotic barriers (eco-geographical isolation and phenology) than post-zygotic barriers, shifting the relative importance of these two classes of reproductive barriers from what is usually seen in naturally produced hybrids where pre-zygotic barriers are the largest contributors to reproductive isolation. Although the long-term fate of neo-hybrids is still to be determined, the massive impact of global change on the dynamics and distribution of biodiversity generates an unprecedented opportunity to study large numbers of unpredicted, and often replicated, hybridization 'experiments', allowing us to peer into the birth and death of evolutionary lineages. PMID:27214560

  5. From hybrid swarms to swarms of hybrids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The introgression of modern humans (Homo sapiens) with Neanderthals 40,000 YBP after a half-million years of separation, may have led to the best example of a hybrid swarm on earth. Modern trade and transportation in support of the human hybrids has continued to introduce additional species, genotyp...

  6. Towards a synergy framework across neuroscience and robotics: Lessons learned and open questions. Reply to comments on: "Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands"

    NASA Astrophysics Data System (ADS)

    Santello, Marco; Bianchi, Matteo; Gabiccini, Marco; Ricciardi, Emiliano; Salvietti, Gionata; Prattichizzo, Domenico; Ernst, Marc; Moscatelli, Alessandro; Jorntell, Henrik; Kappers, Astrid M. L.; Kyriakopoulos, Kostas; Schaeffer, Alin Abu; Castellini, Claudio; Bicchi, Antonio

    2016-07-01

    We would like to thank all commentators for their insightful commentaries. Thanks to their diverse and complementary expertise in neuroscience and robotics, the commentators have provided us with the opportunity to further discuss state-of-the-art and gaps in the integration of neuroscience and robotics reviewed in our article. We organized our reply in two sections that capture the main points of all commentaries [1-9]: (1) Advantages and limitations of the synergy approach in neuroscience and robotics, and (2) Learning and role of sensory feedback in biological and robotics synergies.

  7. Working hard to make a simple definition of synergies. Comment on: "Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands" by Marco Santello et al.

    NASA Astrophysics Data System (ADS)

    Alessandro, Cristiano; Oliveira Barroso, Filipe; Tresch, Matthew

    2016-07-01

    The paper "Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands" [1] presents a comprehensive review of the work carried out as part of the EU funded project "The Hand Embodied". The work uses the concept of "synergy" to study the neuromuscular control of the human hand and to design novel robotics systems. The project has been very productive and has made important contributions. We are therefore confident that it will lead to further advancements and experiments in the future.

  8. Mesoscale hybrid calibration artifact

    DOEpatents

    Tran, Hy D.; Claudet, Andre A.; Oliver, Andrew D.

    2010-09-07

    A mesoscale calibration artifact, also called a hybrid artifact, suitable for hybrid dimensional measurement and the method for make the artifact. The hybrid artifact has structural characteristics that make it suitable for dimensional measurement in both vision-based systems and touch-probe-based systems. The hybrid artifact employs the intersection of bulk-micromachined planes to fabricate edges that are sharp to the nanometer level and intersecting planes with crystal-lattice-defined angles.

  9. Homoploid hybrid expectations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Homoploid hybrid speciation occurs when a stable, fertile, and reproductively isolated lineage results from hybridization between two distinct species without a change in ploidy level. Reproductive isolation between a homoploid hybrid species and its parents is generally attained via chromosomal re...

  10. Hybrid quantum information processing

    SciTech Connect

    Furusawa, Akira

    2014-12-04

    I will briefly explain the definition and advantage of hybrid quantum information processing, which is hybridization of qubit and continuous-variable technologies. The final goal would be realization of universal gate sets both for qubit and continuous-variable quantum information processing with the hybrid technologies. For that purpose, qubit teleportation with a continuousvariable teleporter is one of the most important ingredients.

  11. Hybrid rocket instability

    NASA Technical Reports Server (NTRS)

    Greiner, B.; Frederick, R. A., Jr.

    1993-01-01

    The paper provides a brief review of theoretical and experimental studies concerned with hybrid rocket instability. The instabilities discussed include atomization and mixing instabilities, chuffing instabilities, pressure coupled combustion instabilities, and vortex shedding. It is emphasized that the future use of hybrid motor systems as viable design alternatives will depend on a better understanding of hybrid instability.

  12. Hybrid rocket instability

    NASA Astrophysics Data System (ADS)

    Greiner, B.; Frederick, R. A., Jr.

    1993-06-01

    The paper provides a brief review of theoretical and experimental studies concerned with hybrid rocket instability. The instabilities discussed include atomization and mixing instabilities, chuffing instabilities, pressure coupled combustion instabilities, and vortex shedding. It is emphasized that the future use of hybrid motor systems as viable design alternatives will depend on a better understanding of hybrid instability.

  13. Hybrid armature projectile

    DOEpatents

    Hawke, R.S.; Asay, J.R.; Hall, C.A.; Konrad, C.H.; Sauve, G.L.; Shahinpoor, M.; Susoeff, A.R.

    1993-03-02

    A projectile for a railgun that uses a hybrid armature and provides a seed block around part of the outer surface of the projectile to seed the hybrid plasma brush. In addition, the hybrid armature is continuously vaporized to replenish plasma in a plasma armature to provide a tandem armature and provides a unique ridge and groove to reduce plasma blowby.

  14. Hybrid armature projectile

    DOEpatents

    Hawke, Ronald S.; Asay, James R.; Hall, Clint A.; Konrad, Carl H.; Sauve, Gerald L.; Shahinpoor, Mohsen; Susoeff, Allan R.

    1993-01-01

    A projectile for a railgun that uses a hybrid armature and provides a seed block around part of the outer surface of the projectile to seed the hybrid plasma brush. In addition, the hybrid armature is continuously vaporized to replenish plasma in a plasma armature to provide a tandem armature and provides a unique ridge and groove to reduce plasama blowby.

  15. Administrative Synergy

    ERIC Educational Resources Information Center

    Hewitt, Kimberly Kappler; Weckstein, Daniel K.

    2012-01-01

    One of the biggest obstacles to overcome in creating and sustaining an administrative professional learning community (PLC) is time. Administrators are constantly deluged by the tyranny of the urgent. It is a Herculean task to carve out time for PLCs, but it is imperative to do so. In this article, the authors describe how an administrative PLC…

  16. Transcription Factor Pip Can Enhance DNA Binding by E47, Leading to Transcriptional Synergy Involving Multiple Protein Domains

    PubMed Central

    Nagulapalli, Sujatha; Atchison, Michael L.

    1998-01-01

    The transcription factors E2A (E12/E47) and Pip are both required for normal B-cell development. Each protein binds to regulatory sequences within various immunoglobulin enhancer elements. Activity of E2A proteins can be regulated by interactions with other proteins which influence their DNA binding or activation potential. Similarly, Pip function can be influenced by interaction with the protein PU.1, which can recruit Pip to bind to DNA. We show here that a previously unidentified Pip binding site resides adjacent to the E2A binding site within the immunoglobulin κ 3′ enhancer. Both of these binding sites are crucial for high-level enhancer activity. We found that E47 and Pip can functionally interact to generate a very potent 100-fold transcriptional synergy. Through a series of mutagenesis experiments, we identified the Pip sequences necessary for transcriptional activation and for synergy with E47. Two synergy domains (residues 140 to 207 and 300 to 420) in addition to the Pip DNA binding domain (residues 1 to 134) are required for maximal synergy with E47. We also identified a Pip domain (residues 207 to 300) that appears to mask Pip transactivation potential. Part of the synergy mechanism between E47 and Pip appears to involve the ability of Pip to increase DNA binding by E47, perhaps by inducing a conformational change in the E47 protein. E47 may also induce a conformational change in Pip which unmasks sequences important for transcriptional activity. Based upon our results, we propose a model for E47-Pip transcriptional synergy. PMID:9671474

  17. Grasping synergies: A motor-control approach to the mirror neuron mechanism

    NASA Astrophysics Data System (ADS)

    D'Ausilio, Alessandro; Bartoli, Eleonora; Maffongelli, Laura

    2015-03-01

    The discovery of mirror neurons revived interest in motor theories of perception, fostering a number of new studies as well as controversies. In particular, the degree of motor specificity with which others' actions are simulated is highly debated. Human corticospinal excitability studies support the conjecture that a mirror mechanism encodes object-directed goals or low-level kinematic features of others' reaching and grasping actions. These interpretations lead to different experimental predictions and implications for the functional role of the simulation of others' actions. We propose that the representational granularity of the mirror mechanism cannot be any different from that of the motor system during action execution. Hence, drawing from motor control models, we propose that the building blocks of the mirror mechanism are the relatively few motor synergies explaining the variety of hand functions. The recognition of these synergies, from action observation, can be potentially very robust to visual noise and thus demonstrate a clear advantage of using motor knowledge for classifying others' action.

  18. A Systems Biology Approach to Uncovering Pharmacological Synergy in Herbal Medicines with Applications to Cardiovascular Disease

    PubMed Central

    Wang, Xia; Xu, Xue; Tao, Weiyang; Li, Yan; Wang, Yonghua; Yang, Ling

    2012-01-01

    Background. Clinical trials reveal that multiherb prescriptions of herbal medicine often exhibit pharmacological and therapeutic superiority in comparison to isolated single constituents. However, the synergistic mechanisms underlying this remain elusive. To address this question, a novel systems biology model integrating oral bioavailability and drug-likeness screening, target identification, and network pharmacology method has been constructed and applied to four clinically widely used herbs Radix Astragali Mongolici, Radix Puerariae Lobatae, Radix Ophiopogonis Japonici, and Radix Salviae Miltiorrhiza which exert synergistic effects of combined treatment of cardiovascular disease (CVD). Results. The results show that the structural properties of molecules in four herbs have substantial differences, and each herb can interact with significant target proteins related to CVD. Moreover, the bioactive ingredients from different herbs potentially act on the same molecular target (multiple-drug-one-target) and/or the functionally diverse targets but with potentially clinically relevant associations (multiple-drug-multiple-target-one-disease). From a molecular/systematic level, this explains why the herbs within a concoction could mutually enhance pharmacological synergy on a disease. Conclusions. The present work provides a new strategy not only for the understanding of pharmacological synergy in herbal medicine, but also for the rational discovery of potent drug/herb combinations that are individually subtherapeutic. PMID:23243453

  19. The neuroendocrine response to stress under the effect of drugs: Negative synergy between amphetamine and stressors.

    PubMed

    Gómez-Román, Almudena; Ortega-Sánchez, Juan A; Rotllant, David; Gagliano, Humberto; Belda, Xavier; Delgado-Morales, Raúl; Marín-Blasco, Ignacio; Nadal, Roser; Armario, Antonio

    2016-01-01

    There have been numerous studies into the interaction between stress and addictive drugs, yet few have specifically addressed how the organism responds to stress when under the influence of psychostimulants. Thus, we studied the effects of different acute stressors (immobilization, interleukin-1β and forced swimming) in young adult male rats simultaneously exposed to amphetamine (AMPH, 4 mg/kg SC), evaluating classic biological markers. AMPH administration itself augmented the plasma hypothalamic-pituitary-adrenal (HPA) hormones, adrenocorticotropin (ACTH) and corticosterone, without affecting plasma glucose levels. By contrast, this drug dampened the peripheral HPA axis, as well as the response of glucose to the three stressors. We also found that AMPH administration completely blocked the forced swim-induced expression of the corticotropin-releasing hormone (hnCRH) and it partially reduced c-fos expression in the paraventricular nucleus of the hypothalamus (PVN). Indeed, this negative synergy in the forced swim test could even be observed with a lower dose of AMPH (1mg/kg, SC), a dose that is usually received in self-administration experiments. In conclusion, when rats that receive AMPH are subjected to stress, a negative synergy occurs that dampens the prototypic peripheral physiological response to stress and activation of the PVN. PMID:26433325

  20. Techno-ecological synergy as a path toward sustainability of a North American residential system.

    PubMed

    Urban, Robert A; Bakshi, Bhavik R

    2013-02-19

    For any human-designed system to be sustainable, ecosystem services that support it must be readily available. This work explicitly accounts for this dependence by designing synergies between technological and ecological systems. The resulting techno-ecological network mimics nature at the systems level, can stay within ecological constraints, and can identify novel designs that are economically and environmentally attractive that may not be found by the traditional design focus on technological options. This approach is showcased by designing synergies for a typical American suburban home at local and life cycle scales. The objectives considered are carbon emissions, water withdrawal, and cost savings. Systems included in the design optimization include typical ecosystems in suburban yards: lawn, trees, water reservoirs, and a vegetable garden; technological systems: heating, air conditioning, faucets, solar panels, etc.; and behavioral variables: heating and cooling set points. The ecological and behavioral design variables are found to have a significant effect on the three objectives, in some cases rivaling and exceeding the effect of traditional technological options. These results indicate the importance and benefits of explicitly including ecosystems in the design of sustainable systems, something that is rarely done in existing methods. PMID:23294016

  1. Adaptation of the AACN Synergy Model for Patient Care to Critical Care Transport

    PubMed Central

    SWICKARD, SCOTT; SWICKARD, WENDY; REIMER, ANDREW; LINDELL, DEBORAH; WINKELMAN, CHRIS

    2014-01-01

    Today’s health care delivery system relies heavily on interhospital transfer of patients who require higher levels of care. Although numerous tools and algorithms have been used for the prehospital determination of mode of transport, no tool for the transfer of patients between hospitals has been widely accepted. Typically, the interfacility transport decision is left to the discretion of the referring provider, who may or may not be aware of the level of care provided or the means of transport available. A need exists to determine the appropriate level of care required to meet the needs of patients during transport. The American Association of Critical-Care Nurses (AACN) Synergy Model for Patient Care is a patient-centered model that focuses on optimizing patient care by matching the characteristics of the patient with the competencies of the nurse. This model shows significant promise in providing the theoretical backing to guide the decision on the level of care necessary to complete interfacility transfers safely and effectively. This article describes a new tool inspired by the AACN Synergy Model for Patient Care to determine the appropriate level of care required for interfacility transport. PMID:24488887

  2. Electron Bernstein wave-bootstrap current synergy in the National Spherical Torus Experiment

    SciTech Connect

    Harvey, R.W.; Taylor, G.

    2005-05-15

    Current driven by electron Bernstein waves (EBW) and by the electron bootstrap effect are calculated separately and concurrently with a kinetic code to determine the degree of synergy between them. A target {beta}=40% NSTX [M. Ono, S. Kaye, M. Peng et al., Proceedings of the 17th IAEA Fusion Energy Conference, edited by M. Spak (IAEA, Vienna, Austria, 1999), Vol. 3, p. 1135] plasma is examined. A simple bootstrap model in the collisional-quasilinear CQL3D Fokker-Planck code (National Technical Information Service document No. DE93002962) is used in these studies: the transiting electron distributions are connected in velocity space at the trapped-passing boundary to trapped-electron distributions that are displaced radially by a half-banana-width outwards/inwards for the co-passing/counter-passing regions. This model agrees well with standard bootstrap current calculations over the outer 60% of the plasma radius. Relatively small synergy net bootstrap current is obtained for EBW power up to 4 MW. Locally, bootstrap current density increases in proportion to increased plasma pressure, and this effect can significantly affect the radial profile of driven current.

  3. Carbapenems and Rifampin Exhibit Synergy against Mycobacterium tuberculosis and Mycobacterium abscessus

    PubMed Central

    Kaushik, Amit; Makkar, Nayani; Pandey, Pooja; Parrish, Nicole; Singh, Urvashi

    2015-01-01

    An effective regimen for treatment of tuberculosis (TB) is comprised of multiple drugs that inhibit a range of essential cellular activities in Mycobacterium tuberculosis. The effectiveness of a regimen is further enhanced if constituent drugs act with synergy. Here, we report that faropenem (a penem) or biapenem, doripenem, or meropenem (carbapenems), which belong to the β-lactam class of antibiotics, and rifampin, one of the drugs that forms the backbone of TB treatment, act with synergy when combined. One of the reasons (carba)penems are seldom used for treatment of TB is the high dosage levels required, often at the therapeutic limits. The synergistic combination of rifampin and these (carba)penems indicates that (carba)penems can be administered at dosages that are therapeutically relevant. The combination of faropenem and rifampin also limits the frequency of resistant mutants, as we were unable to obtain spontaneous mutants in the presence of these two drugs. The combinations of rifampin and (carba)penems were effective not only against drug-sensitive Mycobacterium tuberculosis but also against drug-resistant clinical isolates that are otherwise resistant to rifampin. A combination of doripenem or biapenem and rifampin also exhibited synergistic activity against Mycobacterium abscessus. Although the MICs of these three drugs alone against M. abscessus are too high to be of clinical relevance, their concentrations in combinations are therapeutically relevant; therefore, they warrant further evaluation for clinical utility to treat Mycobacterium abscessus infection, especially in cystic fibrosis patients. PMID:26259792

  4. Carbapenems and Rifampin Exhibit Synergy against Mycobacterium tuberculosis and Mycobacterium abscessus.

    PubMed

    Kaushik, Amit; Makkar, Nayani; Pandey, Pooja; Parrish, Nicole; Singh, Urvashi; Lamichhane, Gyanu

    2015-10-01

    An effective regimen for treatment of tuberculosis (TB) is comprised of multiple drugs that inhibit a range of essential cellular activities in Mycobacterium tuberculosis. The effectiveness of a regimen is further enhanced if constituent drugs act with synergy. Here, we report that faropenem (a penem) or biapenem, doripenem, or meropenem (carbapenems), which belong to the β-lactam class of antibiotics, and rifampin, one of the drugs that forms the backbone of TB treatment, act with synergy when combined. One of the reasons (carba)penems are seldom used for treatment of TB is the high dosage levels required, often at the therapeutic limits. The synergistic combination of rifampin and these (carba)penems indicates that (carba)penems can be administered at dosages that are therapeutically relevant. The combination of faropenem and rifampin also limits the frequency of resistant mutants, as we were unable to obtain spontaneous mutants in the presence of these two drugs. The combinations of rifampin and (carba)penems were effective not only against drug-sensitive Mycobacterium tuberculosis but also against drug-resistant clinical isolates that are otherwise resistant to rifampin. A combination of doripenem or biapenem and rifampin also exhibited synergistic activity against Mycobacterium abscessus. Although the MICs of these three drugs alone against M. abscessus are too high to be of clinical relevance, their concentrations in combinations are therapeutically relevant; therefore, they warrant further evaluation for clinical utility to treat Mycobacterium abscessus infection, especially in cystic fibrosis patients. PMID:26259792

  5. Prehension synergies during fatigue of a single digit: adaptations in control with referent configurations.

    PubMed

    Singh, Tarkeshwar; Zatsiorsky, Vladimir M; Latash, Mark L

    2014-07-01

    The effects of muscle fatigue on the stability of precision grasps are not well known. The purpose of the current study was to investigate the effects of exercise-induced fatigue of a digit on prehension synergies in a static precision grasp. One group of participants performed the fatiguing exercise using the thumb (group-thumb) and the second group performed the exercise using the index finger (group-index). Grasp force and load-resisting force-stabilizing synergies were weaker during fatigue for group-thumb and showed no significant change for group-index. These results indicate that fatiguing the thumb compromises the stability of the precision grasp more than when the index finger is fatigued. Our results support the idea of hierarchical organization of prehension control. We proffer an explanation of our results based on two control constructs: a) Principle of superposition. This principle states that prehension can be viewed as a superposition of two independent processes controlling the slip and the tilt of the object respectively; and b) The referent configuration hypothesis. According to this hypothesis, the neural control of actions is associated with defining a set of referent values for task-related coordinates (given an external force field) defined as the referent configuration. PMID:24457335

  6. Systems-pharmacology dissection of a drug synergy in imatinib-resistant CML

    PubMed Central

    Carlson, Scott M; Gleixner, Karoline V; Grebien, Florian; Gridling, Manuela; Müller, André C; Breitwieser, Florian P; Bilban, Martin; Colinge, Jacques; Valent, Peter; Bennett, Keiryn L; White, Forest M; Superti-Furga, Giulio

    2014-01-01

    Occurrence of the BCR-ABLT315I gatekeeper mutation is among the most pressing challenges in the therapy of chronic myeloid leukemia (CML). Several BCR-ABL inhibitors have multiple targets and pleiotropic effects that could be exploited for their synergistic potential. Testing combinations of such kinase inhibitors identified a strong synergy between danusertib and bosutinib that exclusively affected CML cells harboring BCR-ABLT315I. To elucidate the underlying mechanisms, we applied a systems-level approach comprising phosphoproteomics, transcriptomics and chemical proteomics. Data integration revealed that both compounds targeted Mapk pathways downstream of BCR-ABL, resulting in impaired activity of c-Myc. Using pharmacological validation, we assessed that the relative contributions of danusertib and bosutinib could be mimicked individually by Mapk inhibitors and collectively by downregulation of c-Myc through Brd4 inhibition. Thus, integration of genome- and proteome-wide technologies enabled the elucidation of the mechanism by which a new drug synergy targets the dependency of BCR-ABLT315I CML cells on c-Myc through nonobvious off targets. PMID:23023260

  7. Characterizing Aerosols over Southeast Asia using the AERONET Data Synergy Tool

    NASA Technical Reports Server (NTRS)

    Giles, David M.; Holben, Brent N.; Eck, Thomas F.; Slutsker, Ilya; Slutsker, Ilya; Welton, Ellsworth, J.; Chin, Mian; Kucsera, Thomas; Schmaltz, Jeffery E.; Diehl, Thomas; Singh, Ramesh P.; Boonjawat, Jariya; Snidvongs, Arond; Le, Huy V.

    2007-01-01

    Biomass burning, urban pollution and dust aerosols have significant impacts on the radiative forcing of the atmosphere over Asia. In order to better quanti@ these aerosol characteristics, the Aerosol Robotic Network (AERONET) has established over 200 sites worldwide with an emphasis in recent years on the Asian continent - specifically Southeast Asia. A total of approximately 15 AERONET sun photometer instruments have been deployed to China, India, Pakistan, Thailand, and Vietnam. Sun photometer spectral aerosol optical depth measurements as well as microphysical and optical aerosol retrievals over Southeast Asia will be analyzed and discussed with supporting ground-based instrument, satellite, and model data sets, which are freely available via the AERONET Data Synergy tool at the AERONET web site (http://aeronet.gsfc.nasa.gov). This web-based data tool provides access to groundbased (AERONET and MPLNET), satellite (MODIS, SeaWiFS, TOMS, and OMI) and model (GOCART and back trajectory analyses) databases via one web portal. Future development of the AERONET Data Synergy Tool will include the expansion of current data sets as well as the implementation of other Earth Science data sets pertinent to advancing aerosol research.

  8. Biologically inspired kinematic synergies enable linear balance control of a humanoid robot.

    PubMed

    Hauser, Helmut; Neumann, Gerhard; Ijspeert, Auke J; Maass, Wolfgang

    2011-05-01

    Despite many efforts, balance control of humanoid robots in the presence of unforeseen external or internal forces has remained an unsolved problem. The difficulty of this problem is a consequence of the high dimensionality of the action space of a humanoid robot, due to its large number of degrees of freedom (joints), and of non-linearities in its kinematic chains. Biped biological organisms face similar difficulties, but have nevertheless solved this problem. Experimental data reveal that many biological organisms reduce the high dimensionality of their action space by generating movements through linear superposition of a rather small number of stereotypical combinations of simultaneous movements of many joints, to which we refer as kinematic synergies in this paper. We show that by constructing two suitable non-linear kinematic synergies for the lower part of the body of a humanoid robot, balance control can in fact be reduced to a linear control problem, at least in the case of relatively slow movements. We demonstrate for a variety of tasks that the humanoid robot HOAP-2 acquires through this approach the capability to balance dynamically against unforeseen disturbances that may arise from external forces or from manipulating unknown loads. PMID:21523489

  9. Confirmation of Maslow's Hypothesis of Synergy: Developing an Acceptance of Selfishness at the Workplace Scale.

    PubMed

    Takaki, Jiro; Taniguchi, Toshiyo; Fujii, Yasuhito

    2016-01-01

    This study aimed to develop a new Acceptance of Selfishness at the Workplace Scale (ASWS) and to confirm Maslow's hypothesis of synergy: if both a sense of contribution and acceptance of selfishness at the workplace are high, workers are psychologically healthy. In a cross-sectional study with employees of three Japanese companies, 656 workers answered a self-administered questionnaire on paper completely (response rate = 66.8%). Each questionnaire was submitted to us in a sealed envelope and analyzed. The ASWS indicated high internal consistency (Cronbach's alpha = 0.86). Significant (p < 0.001) positive moderate correlations between ASWS scores and job control scores support the ASWS's convergent and discriminant validity. Significant (p < 0.001) associations of ASWS scores with psychological distress and work engagement supported the ASWS's criterion validity. In short, ASWS was a psychometrically satisfactory measure. Significant (p < 0.05) interactions between a sense of contribution and acceptance of selfishness at the workplace in linear regression models showed that when those two factors are low, psychological distress becomes high. However, when a sense of contribution and acceptance of selfishness are high, work engagement also becomes high. Thus, Maslow's hypothesis of synergy was confirmed. PMID:27144575

  10. Synergy between bio-based industry and the feed industry through biorefinery.

    PubMed

    Teekens, Amanda M; Bruins, Marieke E; van Kasteren, Johannes Mn; Hendriks, Wouter H; Sanders, Johan Pm

    2016-06-01

    Processing biomass into multi-functional components can contribute to the increasing demand for raw materials for feed and bio-based non-food products. This contribution aims to demonstrate synergy between the bio-based industry and the feed industry through biorefinery of currently used feed ingredients. Illustrating the biorefinery concept, rapeseed was selected as a low priced feed ingredient based on market prices versus crude protein, crude fat and apparent ileal digestible lysine content. In addition it is already used as an alternative protein source in diets and can be cultivated in European climate zones. Furthermore, inclusion level of rapeseed meal in pig diet is limited because of its nutritionally active factors. A conceptual process was developed to improve rapeseeds nutritional value and producing other bio-based building blocks simultaneously. Based on the correlation between market prices of feed ingredients and its protein and fat content, the value of refined products was estimated. Finally, a sensitivity analysis, under two profit scenario, shows that the process is economically feasible. This study demonstrates that using biorefinery processes on feed ingredients can improve feed quality. In conjunction, it produces building blocks for a bio-based industry and creates synergy between bio-based and feed industry for more efficient use of biomass. © 2015 Society of Chemical Industry. PMID:26694859

  11. Synergy Potential of Indole Alkaloids and Its Derivative against Drug-resistant Escherichia coli.

    PubMed

    Dwivedi, Gaurav Raj; Gupta, Shikha; Maurya, Anupam; Tripathi, Shubhandra; Sharma, Ashok; Darokar, Mahendra P; Srivastava, Santosh K

    2015-12-01

    Antibacterial and synergy potential of naturally occurring indole alkaloids (IA): 10-methoxy tetrahydroalstonine (1), isoreserpiline (2), 10 and 11 demethoxyreserpiline (3), reserpiline (4), serpentine (5), ajmaline (6), ajmalicine (7), yohimbine (8), and α-yohimbine (9) was evaluated using microbroth dilution assay. Further, α-yohimbine (9) was chemically transformed into six semisynthetic derivatives (9A-9F), and their antibacterial and synergy potential in combination with nalidixic acid (NAL) against E. coli strains CA8000 and DH5α were also evaluated. The IA 1, 2, 4, 5, 9 and the derivative 9F showed eightfold reduction in the MIC of NAL against the DH5α and four- to eightfold reduction against CA8000. These alkaloids also reduced MIC of another antibiotic, tetracycline up to 8folds, against the MDREC-KG4, a multidrug-resistant clinical isolate of E. coli. Mode of action study of these alkaloids showed efflux pumps inhibitory potential, which was supported by their in silico binding affinity and downregulation of efflux pump genes. These results may be of great help in the development of cost-effective antibacterial combinations for treating patients infected with multidrug-resistant Gram-negative infections. PMID:26132412

  12. Probing Corticospinal Recruitment Patterns and Functional Synergies with Transcranial Magnetic Stimulation

    PubMed Central

    Mathew, James; Kübler, Angelika; Bauer, Robert; Gharabaghi, Alireza

    2016-01-01

    Background: On the one hand, stimulating the motor cortex at different spots may activate the same muscle and result in a muscle-specific cortical map. Maps of different muscles, which are functionally coupled, may present with a large overlap but may also show a relevant variability. On the other hand, stimulation of the motor cortex at one spot with different stimulation intensities results in a characteristic input–output (IO) curve for one specific muscle but may simultaneously also activate different, functionally coupled muscles. A comparison of the cortical map overlap of synergistic muscles and their IO curves has not yet been carried out. Objective: The aim of this study was to probe functional synergies of forearm muscles with transcranial magnetic stimulation by harnessing the convergence and divergence of the corticospinal output. Methods: We acquired bihemispheric cortical maps and IO curves of the extensor carpi ulnaris, extensor carpi radialis, and extensor digitorum communis muscles by subjecting 11 healthy subjects to both monophasic and biphasic pulse waveforms. Results: The degree of synergy between pairs of forearm muscles was captured by the overlap of the cortical motor maps and the respective IO curves which were influenced by the pulse waveform. Monophasic and biphasic stimulation were particularly suitable for disentangling synergistic muscles in the right and left hemisphere, respectively. Conclusion: Combining IO curves and different pulse waveforms may provide complementary information on neural circuit dynamics and corticospinal recruitment patterns of synergistic muscles and their neuroplastic modulation. PMID:27458344

  13. Plasmas meet nanoparticles—where synergies can advance the frontier of medicine

    NASA Astrophysics Data System (ADS)

    Kong, M. G.; Keidar, M.; Ostrikov, K.

    2011-05-01

    Nanoparticles and low-temperature plasmas have been developed, independently and often along different routes, to tackle the same set of challenges in biomedicine. There are intriguing similarities and contrasts in their interactions with cells and living tissues, and these are reflected directly in the characteristics and scope of their intended therapeutic solutions, in particular their chemical reactivity, selectivity against pathogens and cancer cells, safety to healthy cells and tissues and targeted delivery to diseased tissues. Time has come to ask the inevitable question of possible plasma-nanoparticle synergy and the related benefits to the development of effective, selective and safe therapies for modern medicine. This perspective paper offers a detailed review of the strengths and weakenesses of nanomedicine and plasma medicine as a stand-alone technology, and then provides a critical analysis of some of the major opportunities enabled by synergizing nanotechnology and plasma technology. It is shown that the plasma-nanoparticle synergy is best captured through plasma nanotechnology and its benefits for medicine are highly promising.

  14. Method of Drawing Up a Road Map that Considers the Synergy Effect for IT Investment

    NASA Astrophysics Data System (ADS)

    Nakagawa, Tadasuke; Tani, Shigeyuki; Akatsu, Masaharu; Komoda, Norihisa

    IT governance lacks a comprehensive vision of the investment in two or more projects. It is necessary to decide the priority level that maximizes the effect under the constraint conditions. The problem is complex because while sometimes a greater effect can be obtained by introducing two or more measures at the same time, other times the effect of two measures introduced at the same time might not be significant. Although there is thus a synergy effect when two or more measures are introduced, no method for drawing up an investment-decision road map considered that effect. We therefore developed one. What a decision-maker thinks about when considering the introduction of two or more measures can be visualized by drawing up a comprehensive road map that satisfies constraint conditions such as effectiveness of measure, budget, time, staff size, order of introduction, the synergy effect. Road map users can easily reach a consensus because the map, by taking into account the constraint conditions and the investment decision-making process, helps them logically explain the order in which the measures should be introduced.

  15. The metaphor-gestalt synergy underlying the self-organisation of perception as a semiotic process.

    PubMed

    Rail, David

    2013-04-01

    Recently the basis of concept and language formation has been redefined by the proposal that they both stem from perception and embodiment. The experiential revolution has lead to a far more integrated and dynamic understanding of perception as a semiotic system. The emergence of meaning in the perceptual process stems from the interaction between two key mechanisms. These are first, the generation of schemata through recurrent sensorimotor activity (SM) that underlies category and language formation (L). The second is the interaction between metaphor (M) and gestalt mechanisms (G) that generate invariant mappings beyond the SM domain that both conserve and diversify our understanding and meaning potential. We propose an important advance in our understanding of perception as a semiotic system through exploring the affect of self-organising to criticality where hierarchical behaviour becomes widely integrated through 1/f process and isomorphisms. Our proposal leads to several important implications. First, that SM and L form a functional isomorphism depicted as SM <=> L. We contend that SM <=> L is emergent, corresponding to the phenomenal self. Second, meaning structures the isomorphism SM <=>L through the synergy between M and G (M-G). M-G synergy is based on a combination of structuring and imagination. We contend that the interaction between M-G and SM <=> L functions as a macro-micro comutation that governs perception as semiosis. We discuss how our model relates to current research in fractal time and verb formation. PMID:23517606

  16. The role of muscle synergies in myoelectric control: trends and challenges for simultaneous multifunction control

    NASA Astrophysics Data System (ADS)

    Ison, Mark; Artemiadis, Panagiotis

    2014-10-01

    Myoelectric control is filled with potential to significantly change human-robot interaction due to the ability to non-invasively measure human motion intent. However, current control schemes have struggled to achieve the robust performance that is necessary for use in commercial applications. As demands in myoelectric control trend toward simultaneous multifunctional control, multi-muscle coordinations, or synergies, play larger roles in the success of the control scheme. Detecting and refining patterns in muscle activations robust to the high variance and transient changes associated with surface electromyography is essential for efficient, user-friendly control. This article reviews the role of muscle synergies in myoelectric control schemes by dissecting each component of the scheme with respect to associated challenges for achieving robust simultaneous control of myoelectric interfaces. Electromyography recording details, signal feature extraction, pattern recognition and motor learning based control schemes are considered, and future directions are proposed as steps toward fulfilling the potential of myoelectric control in clinically and commercially viable applications.

  17. Modeling the synergy between HSV-2 and HIV and potential impact of HSV-2 therapy.

    PubMed

    Feng, Zhilan; Qiu, Zhipeng; Sang, Zi; Lorenzo, Christina; Glasser, John

    2013-10-01

    Mounting evidence indicates that genital HSV-2 infection may increase susceptibility to HIV infection and that co-infection may increase infectiousness. Accordingly, antiviral treatment of people with HSV-2 may mitigate the incidence of HIV in populations where both pathogens occur. To better understand the epidemiological synergy between HIV and HSV-2, we formulate a deterministic compartmental model that describes the transmission dynamics of these pathogens. Unlike earlier models, ours incorporates gender and heterogeneous mixing between activity groups. We derive explicit expressions for the reproduction numbers of HSV-2 and HIV, as well as the invasion reproduction numbers via next generation matrices. A qualitative analysis of the system includes the local and global behavior of the model. Simulations reinforce these analytical results and demonstrate epidemiological synergy between HSV-2 and HIV. In particular, numerical results show that HSV-2 favors the invasion of HIV, may dramatically increase the peak as well as reducing the time-to-peak of HIV prevalence, and almost certainly has exacerbated HIV epidemics. The potential population-level impact of HSV-2 on HIV is demonstrated by calculating the fraction of HIV infections attributable to HSV-2 and the difference between HIV prevalence in the presence and absence of HSV-2. The potential impact of treating people with HSV-2 on HIV control is demonstrated by comparing HIV prevalence with and without HSV-2 therapy. Most importantly, we illustrate that the aforementioned aspects of the population dynamics can be significantly influenced by the sexual structure of the population. PMID:23850537

  18. Multimodal Iron Oxide Nanoparticles for Hybrid Biomedical Imaging

    PubMed Central

    Heidt, Timo; Nahrendorf, Matthias

    2012-01-01

    Iron oxide core nanoparticles are attractive imaging agents because their material properties allow the tuning of pharmacokinetics as well as attachment of multiple moieties to their surface. In addition to affinity ligands, these include fluorochromes and radioisotopes for detection with optical and nuclear imaging. As the iron oxide core can be detected by MRI, options for combining imaging modalities are manifold. Already, preclinical imaging strategies combine non-invasive imaging with higher resolution techniques such as intravital microscopy to gain unprecedented insight into steady state biology and disease. Going forward, hybrid iron oxide nanoparticles will likely help to merge modalities, creating a synergy that enables imaging in basic research and, potentially, also in the clinic. PMID:23065771

  19. Muscle Synergies in Cycling after Incomplete Spinal Cord Injury: Correlation with Clinical Measures of Motor Function and Spasticity

    PubMed Central

    Barroso, Filipe O.; Torricelli, Diego; Bravo-Esteban, Elisabeth; Taylor, Julian; Gómez-Soriano, Julio; Santos, Cristina; Moreno, Juan C.; Pons, José L.

    2016-01-01

    Background: After incomplete spinal cord injury (iSCI), patients suffer important sensorimotor impairments, such as abnormal locomotion patterns and spasticity. Complementary to current clinical diagnostic procedures, the analysis of muscle synergies has emerged as a promising tool to study muscle coordination, which plays a major role in the control of multi-limb functional movements. Objective: Based on recent findings suggesting that walking and cycling share similar synergistic control, the analysis of muscle synergies during cycling might be explored as an early descriptor of gait-related impaired control. This idea was split into the following two hypotheses: (a) iSCI patients present a synergistic control of muscles during cycling; (b) muscle synergies outcomes extracted during cycling correlate with clinical measurements of gait performance and/or spasticity. Methods: Electromyographic (EMG) activity of 13 unilateral lower limb muscles was recorded in a group of 10 healthy individuals and 10 iSCI subjects during cycling at four different cadences. A non-negative matrix factorization (NNMF) algorithm was applied to identify synergistic components (i.e., activation coefficients and muscle synergy vectors). Reconstruction goodness scores (VAF and r2) were used to evaluate the ability of a given number of synergies to reconstruct the EMG signals. A set of metrics based on the similarity between pathologic and healthy synergies were correlated with clinical scales of gait performance and spasticity. Results: iSCI patients preserved a synergistic control of muscles during cycling. The similarity with the healthy reference was consistent with the degree of the impairment, i.e., less impaired patients showed higher similarities with the healthy reference. There was a strong correlation between reconstruction goodness scores at 42 rpm and motor performance scales (TUG, 10-m test and WISCI II). On the other hand, the similarity between the healthy and affected

  20. Meta-instable Stress States and Faulting Synergy from Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Ma, J.; Guo, Y.; Zhuo, Y.; Ren, Y.; Zhang, K.; Liu, G.

    2012-12-01

    As a possible mechanism of earthquake, stick-slip has long been studied in laboratory, but little has been studied in detail for the last period of a fault approaching to its instability, in which the general differential stress drops from the peak-value of tectonic stress to the level at the beginning of final instability. We define this short-period as a meta-instable stage. In laboratory, the mechanic sign of whether a sample enters meta-instability state is that the stress released rate transfers from a slow velocity to a fast one. Thus, identifying the meat-instable stress state is theoretically and practically important for potential seismic risk evaluation. In order to obtain a detailed evolution process of meta-instable stage, we conducted a series of experiments with different types of combined faults by use of four types of sensor arrays to record strain, fault displacement, acoustic emission and temperature as well as an infrared thermal image system. Furthermore, digital images of sample surface were taken, by high-speed camera at the sampling rate of 1 kHz during stick-slip, to calculate fault displacement field of sample surface. We compared these multi-physical phenomena during different strike-slip stages, including stress accumulation, deviating linear increase of stress, meta-instability and instability. The preliminary results show as following: (i) The instability of a fault is a converting process from independent activities to synergetic activities; the instability is the end of the synergy, while the synergy of different segments of a fault is a sign of regional stress release; (ii) At the beginning of stress release, the stress deviate the linear trend; it is a transition stage from stress accumulation to stress release, while the release is not dominant; and non-linear temperature change caused by strain is observed. We find a shift pattern of compressive and tensional regions, which is reciprocating to extend along the fault from both the

  1. Deconstructing the Methods and Synergies in Problem-Based Learning, Community-Based Project-Organized Education: Perspectives at the University of Venda, South Africa

    ERIC Educational Resources Information Center

    Netshandama, V. O.; Farrell, Sarah P.

    2006-01-01

    This case study discusses the deconstructions and synergies of problem-based learning (PBL) and community-based project-organized education. The growing literature on these methods lacks in coverage of their synergies and their applicability to meaningful projects with communities as partners. Community-based learning is inherently problem based…

  2. Hybridization and extinction.

    PubMed

    Todesco, Marco; Pascual, Mariana A; Owens, Gregory L; Ostevik, Katherine L; Moyers, Brook T; Hübner, Sariel; Heredia, Sylvia M; Hahn, Min A; Caseys, Celine; Bock, Dan G; Rieseberg, Loren H

    2016-08-01

    Hybridization may drive rare taxa to extinction through genetic swamping, where the rare form is replaced by hybrids, or by demographic swamping, where population growth rates are reduced due to the wasteful production of maladaptive hybrids. Conversely, hybridization may rescue the viability of small, inbred populations. Understanding the factors that contribute to destructive versus constructive outcomes of hybridization is key to managing conservation concerns. Here, we survey the literature for studies of hybridization and extinction to identify the ecological, evolutionary, and genetic factors that critically affect extinction risk through hybridization. We find that while extinction risk is highly situation dependent, genetic swamping is much more frequent than demographic swamping. In addition, human involvement is associated with increased risk and high reproductive isolation with reduced risk. Although climate change is predicted to increase the risk of hybridization-induced extinction, we find little empirical support for this prediction. Similarly, theoretical and experimental studies imply that genetic rescue through hybridization may be equally or more probable than demographic swamping, but our literature survey failed to support this claim. We conclude that halting the introduction of hybridization-prone exotics and restoring mature and diverse habitats that are resistant to hybrid establishment should be management priorities. PMID:27468307

  3. Hybrid Rendering with Scheduling under Uncertainty.

    PubMed

    Tamm, Georg; Krüger, Jens

    2014-05-01

    As scientific data of increasing size is generated by today's simulations and measurements, utilizing dedicated server resources to process the visualization pipeline becomes necessary. In a purely server-based approach, requirements on the client-side are minimal as the client only displays results received from the server. However, the client may have a considerable amount of hardware available, which is left idle. Further, the visualization is put at the whim of possibly unreliable server and network conditions. Server load, bandwidth and latency may substantially affect the response time on the client. In this paper, we describe a hybrid method, where visualization workload is assigned to server and client. A capable client can produce images independently. The goal is to determine a workload schedule that enables a synergy between the two sides to provide rendering results to the user as fast as possible. The schedule is determined based on processing and transfer timings obtained at runtime. Our probabilistic scheduler adapts to changing conditions by shifting workload between server and client, and accounts for the performance variability in the dynamic system. PMID:25309115

  4. Hybrid Rendering with Scheduling under Uncertainty

    PubMed Central

    Tamm, Georg; Krüger, Jens

    2014-01-01

    As scientific data of increasing size is generated by today’s simulations and measurements, utilizing dedicated server resources to process the visualization pipeline becomes necessary. In a purely server-based approach, requirements on the client-side are minimal as the client only displays results received from the server. However, the client may have a considerable amount of hardware available, which is left idle. Further, the visualization is put at the whim of possibly unreliable server and network conditions. Server load, bandwidth and latency may substantially affect the response time on the client. In this paper, we describe a hybrid method, where visualization workload is assigned to server and client. A capable client can produce images independently. The goal is to determine a workload schedule that enables a synergy between the two sides to provide rendering results to the user as fast as possible. The schedule is determined based on processing and transfer timings obtained at runtime. Our probabilistic scheduler adapts to changing conditions by shifting workload between server and client, and accounts for the performance variability in the dynamic system. PMID:25309115

  5. Synergy between middle infrared and millimeter-wave limb sounding of atmospheric temperature and minor constituents

    NASA Astrophysics Data System (ADS)

    Cortesi, Ugo; Del Bianco, Samuele; Ceccherini, Simone; Gai, Marco; Dinelli, Bianca Maria; Castelli, Elisa; Oelhaf, Hermann; Woiwode, Wolfgang; Höpfner, Michael; Gerber, Daniel

    2016-05-01

    Synergistic exploitation of redundant and complementary information from independent observations of the same target remains a major issue in atmospheric remote sounding and increasing attention is devoted to investigate optimized or innovative methods for the combination of two or more measured data sets. This paper focuses on the synergy between middle infrared and millimeter-wave limb sounding measurements of atmospheric composition and temperature and reports the results of a study conducted as part of the preparatory activities of the PREMIER (Process Exploration through Measurements of Infrared and millimeter-wave Emitted Radiation) mission candidate to the Core Missions of the European Space Agency (ESA) Earth Explorer 7. The activity was based on data acquired by the MIPAS-STR (Michelson Interferometer for Passive Atmospheric Sounding - STRatospheric aircraft) and MARSCHALS (Millimetre-wave Airborne Receivers for Spectroscopic CHaracterisation in Atmospheric Limb Sounding) instruments on-board the high-altitude research aircraft M-55 Geophysica during the flight of the PremierEx (PREMIER Experiment) campaign on 10 March 2010 from Kiruna, Sweden, for observation of the Arctic upper troposphere and lower stratosphere. The cloud coverage observed along the flight provided representative test cases to evaluate the synergy in three different scenarios: low clouds in the first part, no clouds in the central part and high tropospheric clouds at the end. The calculation of synergistic profiles of four atmospheric targets (i.e., O3, HNO3, H2O and temperature) was performed using a posteriori combination of individual retrieved profiles, i.e., Level 2 (L2) data rather than simultaneous inversion of observed radiances, i.e., Level 1 (L1) data. An innovative method of data fusion, based on the Measurement Space Solution (MSS) was applied along with the standard approach of inversion of MARSCHALS spectral radiances using MIPAS-STR retrieval products as a priori

  6. Challenges and Opportunities to Developing Synergies Among Diverse Environmental Observatories: FSML, NEON, and GLEON

    NASA Astrophysics Data System (ADS)

    Williamson, C. E.; Weathers, K. C.; Knoll, L. B.; Brentrup, J.

    2012-12-01

    Recent rapid advances in sensor technology and cyberinfrastructure have enabled the development of numerous environmental observatories ranging from local networks at field stations and marine laboratories (FSML) to continental scale observatories such as the National Ecological Observatory Network (NEON) to global scale observatories such as the Global Lake Ecological Observatory Network (GLEON). While divergent goals underlie the initial development of these observatories, and they are often designed to serve different communities, many opportunities for synergies exist. In addition, the use of existing infrastructure may enhance the cost-effectiveness of building and maintaining large scale observatories. For example, FSMLs are established facilities with the staff and infrastructure to host sensor nodes of larger networks. Many field stations have existing staff and long-term databases as well as smaller sensor networks that are the product of a single or small group of investigators with a unique data management system embedded in a local or regional community. These field station based facilities and data are a potentially untapped gold mine for larger continental and global scale observatories; common ecological and environmental challenges centered on understanding the impacts of changing climate, land use, and invasive species often underlie these efforts. The purpose of this talk is to stimulate a dialog on the challenges of merging efforts across these different spatial and temporal scales, as well as addressing how to develop synergies among observatory networks with divergent roots and philosophical approaches. For example, FSMLs have existing long-term databases and facilities, while NEON has sparse past data but a well-developed template and closely coordinated team working in a coherent format across a continental scale. GLEON on the other hand is a grass-roots network of experts in science, information technology, and engineering with a common goal

  7. Synergy between middle infrared and millimetre-wave limb sounding of atmospheric temperature and minor constituents

    NASA Astrophysics Data System (ADS)

    Cortesi, U.; Del Bianco, S.; Ceccherini, S.; Gai, M.; Dinelli, B. M.; Castelli, E.; Oelhaf, H.; Woiwode, W.; Höpfner, M.; Gerber, D.

    2015-11-01

    Synergistic exploitation of redundant and complementary information from independent observations of the same target remains a major issue in atmospheric remote-sounding and increasing attention is devoted to investigate optimised or innovative methods for the combination of two or more measured data sets. This paper is focusing on the synergy between middle infrared and millimetre-wave limb sounding measurements of atmospheric composition and temperature and reports the results of a study conducted as part of the preparatory activities of the PREMIER (Process Exploration through Measurements of Infrared and millimetre wave Emitted Radiation) mission candidate to the Core Missions of ESA Earth Explorer 7. The activity was based on data acquired by the MIPAS-STR (Michelson Interferometer for Passive Atmospheric Sounding - STRatospheric aircraft) and MARSCHALS (Millimetre-wave Airborne Receivers for Spectroscopic CHaracterisation in Atmospheric Limb Sounding) instruments onboard the high altitude research aircraft M-55 Geophysica during the flight of the PremierEx (PREMIER Experiment) campaign on 10 March 2010 from Kiruna, Sweden for observation of the Arctic upper troposphere and lower stratosphere. The cloud coverage observed along the flight provided representative test cases to evaluate the synergy in three different scenarios: low clouds in the first part, no clouds in the central part and high tropospheric clouds at the end. The calculation of synergistic profiles of four atmospheric targets (i.e., O2, HNO3, H2O and temperature) was performed using a posteriori combination of individual retrieved profiles, i.e., Level 2 (L2) data rather than simultaneous inverse processing of observed radiances, i.e., Level 1 (L1) data. An innovative method of data fusion, based on the Measurement Space Solution (MSS) was applied along with the standard approach of inverse processing of MARSCHALS spectral radiances using MIPAS-STR retrieval products as a priori information (L1

  8. Synergy of CAY-1, a Fungicidal Saponin, With Amphotericin B and Itreconazole Against Aspergillus spp and Candida albicans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: CAY-1 (mol.wt. 1243), a fungicidal saponin in cayenne (Capsicum fruitescens) is highly lethal for Aspergillus species, Candida albicans, and Pneumocystis carinii below 24.8 ug/ml. To further characterize CAY-1, synergy studies with amphotericin B (AMB) and itraconazole (IT) were perform...

  9. Research Synergy: The Graduate School of Public Health, the SDSU Research Foundation, and San Diego State University

    ERIC Educational Resources Information Center

    Williams, Stephen J.

    2014-01-01

    The evolution of a research university can take many paths. Described here is a case study of the synergy between the establishment and growth of a primarily graduate school and the commitment to developing a research university, all with the assistance of a separately incorporated non-profit research administration entity. The result has been a…

  10. How to Achieve Synergy between Medical Education and Cognitive Neuroscience? An Exercise on Prior Knowledge in Understanding

    ERIC Educational Resources Information Center

    Ruiter, Dirk J.; van Kesteren, Marlieke T. R.; Fernandez, Guillen

    2012-01-01

    A major challenge in contemporary research is how to connect medical education and cognitive neuroscience and achieve synergy between these domains. Based on this starting point we discuss how this may result in a common language about learning, more educationally focused scientific inquiry, and multidisciplinary research projects. As the topic of…

  11. Synergy between Rhizobium phaseoli and Acidithiobacillus ferrooxidans in the Bioleaching Process of Copper.

    PubMed

    Zheng, Xuecheng; Li, Dongwei

    2016-01-01

    This study investigates the synergy of Rhizobium phaseoli and Acidithiobacillus ferrooxidans in the bioleaching process of copper. The results showed that additional R. phaseoli could increase leaching rate and cell number of A. ferrooxidans. When the initial cell number ratio between A. ferrooxidans and R. phaseoli was 2 : 1, A. ferrooxidans attained the highest final cell number of approximately 2 × 10(8) cells/mL and the highest copper leaching rate of 29%, which is 7% higher than that in the group with A. ferrooxidans only. R. phaseoli may use metabolized polysaccharides from A. ferrooxidans, and organic acids could chelate or precipitate harmful heavy metals to reduce their damage on A. ferrooxidans and promote its growth. Organic acids could also damage the mineral lattice to increase the leaching effect. PMID:26942203

  12. Alginate Lyase Exhibits Catalysis-Independent Biofilm Dispersion and Antibiotic Synergy

    PubMed Central

    Lamppa, John W.

    2013-01-01

    More than 2 decades of study support the hypothesis that alginate lyases are promising therapeutic candidates for treating mucoid Pseudomonas aeruginosa infections. In particular, the enzymes' ability to degrade alginate, a key component of mucoid biofilm matrix, has been the presumed mechanism by which they disrupt biofilms and enhance antibiotic efficacy. The systematic studies reported here show that, in an in vitro model, alginate lyase dispersion of P. aeruginosa biofilms and enzyme synergy with tobramycin are completely decoupled from catalytic activity. In fact, equivalent antibiofilm effects can be achieved with bovine serum albumin or simple amino acids. These results provide new insights into potential mechanisms of alginate lyase therapeutic activity, and they should motivate a careful reexamination of the fundamental assumptions underlying interest in enzymatic biofilm dispersion. PMID:23070175

  13. Synergy analysis as a tool to design and assess an effective stroke rehabilitation.

    PubMed

    Urra, O; Casals, A; Jané, R

    2014-01-01

    The poor rehabilitation success rate, including the cases of ineffective and detrimental adaptations, make stroke a leading cause of disability. Thus, it is essential to recognize the mechanisms driving healthy motor recovery to improve such rate. Stroke alters the Synergy Architecture (SA), the modular muscle control system. So SA analysis may constitute a powerful tool to design and assess rehabilitation procedures. However, current impairment scales do not consider the patient's neuromuscular state. To gain insights into this hypothesis, we recorded multiple myoelectric signals from upper-limb muscles, in healthy subjects, while executing a set of common rehabilitation exercises. We found that SA reveals optimized motor control strategies and the positive effects of the use of visual feedback (VF) on motor control. Furthermore we demonstrate that the right and left arm's SA share the basic structure within the same subject, so we propose using the unaffected limb's SA as a reference motion pattern to be reached through rehabilitation. PMID:25570757

  14. A Desirable Engineer Providing Manifold Prospects Enhanced by Synergy Effect of Science and Liberal Arts

    NASA Astrophysics Data System (ADS)

    Harada, Shoji

    Quick globalization makes prediction of future human activity on production and economy more difficult. This is mainly because of increase in factors affecting relationship among different people with different way of life, culture, tradition and so on. To survive in such complicated world each engineer is desired to provide the knowledge of liberal arts as well as highly specialized knowledge. A synergy power generated by collaborative work of science-and liberal arts-minded way of thinking is a promising tool to unveil difficult world. This paper first describes degradation of liberal arts education during past two decades. Then, several movements for stopping that degradation are introduced in conjunction with the author‧s overseas experiences. Finally, a necessity of bringing up well competitive desirable engineer through collaborative work by university and company is proposed.

  15. 3D Online Visualization and Synergy of NASA A-Train Data Using Google Earth

    NASA Technical Reports Server (NTRS)

    Chen, Aijun; Kempler, Steven; Leptoukh, Gregory; Smith, Peter

    2010-01-01

    This poster presentation reviews the use of Google Earth to assist in three dimensional online visualization of NASA Earth science and geospatial data. The NASA A-Train satellite constellation is a succession of seven sun-synchronous orbit satellites: (1) OCO-2 (Orbiting Carbon Observatory) (will launch in Feb. 2013), (2) GCOM-W1 (Global Change Observation Mission), (3) Aqua, (4) CloudSat, (5) CALIPSO (Cloud-Aerosol Lidar & Infrared Pathfinder Satellite Observations), (6) Glory, (7) Aura. The A-Train makes possible synergy of information from multiple resources, so more information about earth condition is obtained from the combined observations than would be possible from the sum of the observations taken independently

  16. BIOLOGICAL ADHESIVES. Adaptive synergy between catechol and lysine promotes wet adhesion by surface salt displacement.

    PubMed

    Maier, Greg P; Rapp, Michael V; Waite, J Herbert; Israelachvili, Jacob N; Butler, Alison

    2015-08-01

    In physiological fluids and seawater, adhesion of synthetic polymers to solid surfaces is severely limited by high salt, pH, and hydration, yet these conditions have not deterred the evolution of effective adhesion by mussels. Mussel foot proteins provide insights about adhesive adaptations: Notably, the abundance and proximity of catecholic Dopa (3,4-dihydroxyphenylalanine) and lysine residues hint at a synergistic interplay in adhesion. Certain siderophores—bacterial iron chelators—consist of paired catechol and lysine functionalities, thereby providing a convenient experimental platform to explore molecular synergies in bioadhesion. These siderophores and synthetic analogs exhibit robust adhesion energies (E(ad) ≥-15 millijoules per square meter) to mica in saline pH 3.5 to 7.5 and resist oxidation. The adjacent catechol-lysine placement provides a "one-two punch," whereby lysine evicts hydrated cations from the mineral surface, allowing catechol binding to underlying oxides. PMID:26250681

  17. Adaptive synergy between catechol and lysine promotes wet adhesion by surface salt displacement

    NASA Astrophysics Data System (ADS)

    Maier, Greg P.; Rapp, Michael V.; Waite, J. Herbert; Israelachvili, Jacob N.; Butler, Alison

    2015-08-01

    In physiological fluids and seawater, adhesion of synthetic polymers to solid surfaces is severely limited by high salt, pH, and hydration, yet these conditions have not deterred the evolution of effective adhesion by mussels. Mussel foot proteins provide insights about adhesive adaptations: Notably, the abundance and proximity of catecholic Dopa (3,4-dihydroxyphenylalanine) and lysine residues hint at a synergistic interplay in adhesion. Certain siderophores—bacterial iron chelators—consist of paired catechol and lysine functionalities, thereby providing a convenient experimental platform to explore molecular synergies in bioadhesion. These siderophores and synthetic analogs exhibit robust adhesion energies (Ead ≥-15 millijoules per square meter) to mica in saline pH 3.5 to 7.5 and resist oxidation. The adjacent catechol-lysine placement provides a “one-two punch,” whereby lysine evicts hydrated cations from the mineral surface, allowing catechol binding to underlying oxides.

  18. A comprehensive tool to analyse dynamic log files from an Elekta-Synergy accelerator

    NASA Astrophysics Data System (ADS)

    Arumugam, Sankar; Xing, Aitang; Pagulayan, Claire; Holloway, Lois

    2014-03-01

    This study presents the development of a software tool 'Treat Check' to analyse the dynamic log files from an Elekta - Synergy accelerator. The software generates formatted output in the form of a plot presenting errors in various treatment delivery parameters such as gantry angle, Multi Leaf Collimator (MLC) leaf position, jaw position and Monitor Units (MU) for each of the control-points (CP) of the treatment beam. The plots are automatically saved in Portable Document Format (pdf). The software also has the functionality to introduce these treatment delivery errors into the original plan in the Pinnacle (Philips) treatment planning system (TPS) in order to assess the clinical impact of treatment delivery errors on delivered dose.

  19. Agricultural and food chemistry: 50 years of synergy between AGFD and JAFC.

    PubMed

    Seiber, James N; Kleinschmidt, Loreen A

    2009-09-23

    The Division of Agricultural and Food Chemistry (AGFD) and the American Chemical Society had the foresight to launch the Journal of Agricultural and Food Chemistry in 1953. JAFC, still closely connected with the Division, has grown to be the premier international journal in the field, providing an outlet for publishing original research articles, reviews, perspectives, and editorials, for agricultural and food chemists from many nations. JAFC has expanded coverage of current areas of intense interest, such as bioactive constituents of foods, biotechnology, and biobased products and biofuels, as well as continuing strong coverage of such mainstream categories as food chemistry/biochemistry, analytical methods, safety and toxicology, and agrochemistry. In 2008 alone, JAFC published over 1650 peer-reviewed manuscripts, several symposia (largely from AGFD symposia at ACS National Meetings), and a number of reviews. The synergy between AGFD and JAFC offers many benefits and exciting opportunities for advancing the science of agricultural and food chemistry for the future. PMID:19719123

  20. Effect of muscular fatigue on fractal upper limb coordination dynamics and muscle synergies.

    PubMed

    Bueno, Diana R; Lizano, J M; Montano, L

    2015-08-01

    Rehabilitation exercises cause fatigue because tasks are repetitive. Therefore, inevitable human motion performance changes occur during the therapy. Although traditionally fatigue is considered an event that occurs in the musculoskeletal level, this paper studies whether fatigue can be regarded as context that influences lower-dimensional motor control organization and coordination at neural level. Non Negative Factorization Matrix (NNFM) and Detrended Fluctuations Analysis (DFA) are the tools used to analyze the changes in the coordination of motor function when someone is affected by fatigue. The study establishes that synergies remain fairly stable with the onset of fatigue, but the fatigue affects the dynamical coordination understood as a cognitive process. These results have been validated with 9 healthy subjects for three representative exercises for upper limb: biceps, triceps and deltoid. PMID:26737679

  1. Benefits from synergies and advanced technologies for an advanced-technology space station

    NASA Astrophysics Data System (ADS)

    Garrett, L. Bernard; Ferebee, Melvin J., Jr.; Queijo, Manuel J.; Butterfield, Ansel J.

    1991-04-01

    A configuration for a second-generation advanced technology space station has been defined in a series of NASA-sponsored studies. Definitions of subsystems specifically addressed opportunities for beneficial synergistic interactions and those potential synergies and their benefits are identified. One of the more significant synergistic benefits involves the multi-function utilization of water within a large system that generates artificial gravity by rotation. In such a system, water not only provides the necessary crew life support, but also serves as counterrotator mass, as moveable ballast, and as a source for propellant gases. Additionally, the synergistic effects between advanced technology materials, operation at reduced artificial gravity, and lower cabin atmospheric pressure levels show beneficial interactions that can be quantified in terms of reduced mass to orbit.

  2. Prehension synergies: trial-to-trial variability and hierarchical organization of stable performance

    PubMed Central

    Shim, Jae K.; Latash, Mark L.

    2010-01-01

    We studied multi-digit synergies as relations among digit forces and points of their application across multiple repetitions of a static prehensile task. The task required holding a grasped object (14.9 N) against different external torques. Subjects (n=6) performed 25 trials for each torque condition: −1.0, −0.5, 0, +0.5 and +1.0 Nm. In spite of the variability of individual forces and points of their application, stable performance was achieved. Individual performance variables were organized into two subsets. Variables within each subset highly correlated with each other (the coefficients of correlation were close to ±1.0) while there was no correlation among variables from different subsets. The two subsets were associated with two components of the prehension task: grasp control (preventing an object from slipping out of the hand) and torque control (maintaining a desired object orientation). PMID:12898101

  3. Synergy among transition element, nitrogen, and carbon for oxygen reduction reaction in alkaline medium

    NASA Astrophysics Data System (ADS)

    Li, Zhou Peng; Liu, Zi Xuan; Zhu, Kun Ning; Li, Zhuo; Liu, Bin Hong

    2012-12-01

    A series of M-doped polypyrrole (PPy)-modified BP2000 catalysts (M = Mn, Fe, Co, Ni, and Cu) are synthesized using the hydrothermal method. The synergy among a transition element, nitrogen, and carbon for oxygen reduction reaction (ORR) in alkaline medium is discussed based on the physical characterization and electrochemical analyses of the Co-doped PPy-modified BP2000. PPy is found to adhere carbon black particles together to form a porous 3D network during the PPy modification on BP2000. PPy reconfiguration occurs during the hydrothermal treatment process. The individual interactions between BP and PPy, BP and Co, and Co and PPy exhibit insignificant effects on the enhancement of ORR. The cooperative interaction among Co, N, and C plays a very important role in the enhancement of ORR. The doping effect of transition-metal salt on ORR enhancement depends on the nature of the transition element and the corresponding anion.

  4. Spectroscopic and Computational Insights on Catalytic Synergy in Bimetallic Aluminophosphate Catalysts.

    PubMed

    Potter, Matthew E; Paterson, A James; Mishra, Bhoopesh; Kelly, Shelly D; Bare, Simon R; Corà, Furio; Levy, Alan B; Raja, Robert

    2015-07-01

    A combined electronic structure computational and X-ray absorption spectroscopy study was used to investigate the nature of the active sites responsible for catalytic synergy in Co-Ti bimetallic nanoporous frameworks. Probing the nature of the molecular species at the atomic level has led to the identification of a unique Co-O-Ti bond, which serves as the loci for the superior performance of the bimetallic catalyst, when compared with its analogous monometallic counterpart. The structural and spectroscopic features associated with this active site have been characterized and contrasted, with a view to affording structure-property relationships, in the wider context of designing sustainable catalytic oxidations with porous solids. PMID:26076192

  5. Neuromotor recovery from stroke: computational models at central, functional, and muscle synergy level

    PubMed Central

    Casadio, Maura; Tamagnone, Irene; Summa, Susanna; Sanguineti, Vittorio

    2013-01-01

    Computational models of neuromotor recovery after a stroke might help to unveil the underlying physiological mechanisms and might suggest how to make recovery faster and more effective. At least in principle, these models could serve: (i) To provide testable hypotheses on the nature of recovery; (ii) To predict the recovery of individual patients; (iii) To design patient-specific “optimal” therapy, by setting the treatment variables for maximizing the amount of recovery or for achieving a better generalization of the learned abilities across different tasks. Here we review the state of the art of computational models for neuromotor recovery through exercise, and their implications for treatment. We show that to properly account for the computational mechanisms of neuromotor recovery, multiple levels of description need to be taken into account. The review specifically covers models of recovery at central, functional and muscle synergy level. PMID:23986688

  6. Uncovering Tensions and Capitalizing on Synergies in HIV/AIDS and Antiviolence Programs

    PubMed Central

    Dunbar, Megan S.; Krishnan, Suneeta; Hatcher, Abigail M.; Sawires, Sharif

    2011-01-01

    Research frequently points to the need to empower women to effectively combat the twin epidemics of HIV/AIDS and gender-based violence. Simultaneously, there has been increased attention given to working with men in gender equality efforts. The latter approach intervenes on masculinities as part of the fight against HIV/AIDS and violence. No research has considered these 2 lines of work side by side to address several important questions: What are the points of overlap, and the tensions and contradictions between these 2 approaches? What are the limitations and unintended consequences of each? We analyzed these 2 parallel research trends and made suggestions for how to capitalize on the synergies that come from bolstering each position with the strengths of the other. PMID:21164091

  7. Synergy between Rhizobium phaseoli and Acidithiobacillus ferrooxidans in the Bioleaching Process of Copper

    PubMed Central

    Zheng, Xuecheng; Li, Dongwei

    2016-01-01

    This study investigates the synergy of Rhizobium phaseoli and Acidithiobacillus ferrooxidans in the bioleaching process of copper. The results showed that additional R. phaseoli could increase leaching rate and cell number of A. ferrooxidans. When the initial cell number ratio between A. ferrooxidans and R. phaseoli was 2 : 1, A. ferrooxidans attained the highest final cell number of approximately 2 × 108 cells/mL and the highest copper leaching rate of 29%, which is 7% higher than that in the group with A. ferrooxidans only. R. phaseoli may use metabolized polysaccharides from A. ferrooxidans, and organic acids could chelate or precipitate harmful heavy metals to reduce their damage on A. ferrooxidans and promote its growth. Organic acids could also damage the mineral lattice to increase the leaching effect. PMID:26942203

  8. Benefits from synergies and advanced technologies for an advanced-technology space station

    NASA Technical Reports Server (NTRS)

    Garrett, L. Bernard; Ferebee, Melvin J., Jr.; Queijo, Manuel J.; Butterfield, Ansel J.

    1991-01-01

    A configuration for a second-generation advanced technology space station has been defined in a series of NASA-sponsored studies. Definitions of subsystems specifically addressed opportunities for beneficial synergistic interactions and those potential synergies and their benefits are identified. One of the more significant synergistic benefits involves the multi-function utilization of water within a large system that generates artificial gravity by rotation. In such a system, water not only provides the necessary crew life support, but also serves as counterrotator mass, as moveable ballast, and as a source for propellant gases. Additionally, the synergistic effects between advanced technology materials, operation at reduced artificial gravity, and lower cabin atmospheric pressure levels show beneficial interactions that can be quantified in terms of reduced mass to orbit.

  9. Utilizing movement synergies to improve decoding performance for a brain machine interface

    PubMed Central

    Wong, Yan T.; Putrino, David; Weiss, Adam; Pesaran, Bijan

    2014-01-01

    A major challenge facing the development of high degree of freedom (DOF) brain machine interface (BMI) devices is a limited ability to provide prospective users with independent control of many DOFs when using a complex prosthesis. It has been previously shown that a large range of complex hand postures can be replicated using a relatively low number of movement synergies. Thus, a high DOF joint space, such as the one the hand resides in, may be decomposed via principal component analysis (PCA) into a lower DOF (eigen-reach) space that contains most of the variance of the original movements. By decoding in this eigen-reach space, BMI users need only control a few eigen-reach values to be able to make movements using all DOFs in the arm and hand. In this paper we examine how using PCA before decoding neural activity may lead to improvements in decoding performance. PMID:24109681

  10. A Tool for Balance Control Training Using Muscle Synergies and Multimodal Interfaces

    PubMed Central

    Galeano, D.; Brunetti, F.; Torricelli, D.; Piazza, S.; Pons, J. L.

    2014-01-01

    Balance control plays a key role in neuromotor rehabilitation after stroke or spinal cord injuries. Computerized dynamic posturography (CDP) is a classic technological tool to assess the status of balance control and to identify potential disorders. Despite the more accurate diagnosis generated by these tools, the current strategies to promote rehabilitation are still limited and do not take full advantage of the technologies available. This paper presents a novel balance training platform which combines a CDP device made from low-cost interfaces, such as the Nintendo Wii Balance Board and the Microsoft Kinect. In addition, it integrates a custom electrical stimulator that uses the concept of muscle synergies to promote natural interaction. The aim of the platform is to support the exploration of innovative multimodal therapies. Results include the technical validation of the platform using mediolateral and anteroposterior sways as basic balance training therapies. PMID:24982896

  11. Plasma-Photocatalyst Interaction for VOC Removal: Origin of the Synergy

    NASA Astrophysics Data System (ADS)

    Rousseau, Antoine

    2007-10-01

    It is well known that the coupling of an atmospheric non-thermal plasma with catalytic materials lead to synergetic effects for the abatement of some volatiles organic compounds (VOC). We analyze, here, the mechanisms of such a synergy where the catalyst is a porous semi-conductor (TiO2). Different porous materials are compared: silica fibers possibly containing SiO2 and/or TiO2 nanoparticles. The respective influence of the porosity versus the chemical type of the catalyst is investigated and the oxidizing species are identified using two complementary approaches. 1) Efficiency of the plasma-catalyst coupling in a dielectric barrier discharge (DBD) at atmospheric pressure, 2) Plasma-catalytic surface interaction in a pulsed low pressure discharge. It is shown that the VOC oxidation scales as a function of the specific injected energy and occurs mainly on the porous surface due to short-life species produced the plasma [1-3]; Time resolved and in-situ measurements using laser absorption spectroscopy and emission spectroscopy in a low-pressure experiment have shown that i) plasma-TiO2 synergy is also evidenced at low pressure[4], ii) O atoms are reversively adsorbed on porous nanoparticles of TiO2; their desorption occur during the first millisecond of a plasma pulse [5], iii) air-plasma pre-treatment of the porous material leads to an enhancement of VOC adsorption on porous TiO2 and has no influence on porous silica. [1] U. Roland et al. Catalysis Today 73 315--323 [2] F. Thevenet et al. Catal. Today 122 (2007) 186--194 [3] F. Thevenet et al. International Journal of Plasma Environmental Science and Technology, 1, (2007), 52-56 [4] A. Rousseau et al. Appl. Phys. Let. 87, 221501 (2005) [5] Allegraud et al. J. Phys. D. : Appl. Phys submitted.

  12. Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects.

    PubMed

    Russo, Ethan B

    2011-08-01

    Tetrahydrocannabinol (THC) has been the primary focus of cannabis research since 1964, when Raphael Mechoulam isolated and synthesized it. More recently, the synergistic contributions of cannabidiol to cannabis pharmacology and analgesia have been scientifically demonstrated. Other phytocannabinoids, including tetrahydrocannabivarin, cannabigerol and cannabichromene, exert additional effects of therapeutic interest. Innovative conventional plant breeding has yielded cannabis chemotypes expressing high titres of each component for future study. This review will explore another echelon of phytotherapeutic agents, the cannabis terpenoids: limonene, myrcene, α-pinene, linalool, β-caryophyllene, caryophyllene oxide, nerolidol and phytol. Terpenoids share a precursor with phytocannabinoids, and are all flavour and fragrance components common to human diets that have been designated Generally Recognized as Safe by the US Food and Drug Administration and other regulatory agencies. Terpenoids are quite potent, and affect animal and even human behaviour when inhaled from ambient air at serum levels in the single digits ng·mL(-1) . They display unique therapeutic effects that may contribute meaningfully to the entourage effects of cannabis-based medicinal extracts. Particular focus will be placed on phytocannabinoid-terpenoid interactions that could produce synergy with respect to treatment of pain, inflammation, depression, anxiety, addiction, epilepsy, cancer, fungal and bacterial infections (including methicillin-resistant Staphylococcus aureus). Scientific evidence is presented for non-cannabinoid plant components as putative antidotes to intoxicating effects of THC that could increase its therapeutic index. Methods for investigating entourage effects in future experiments will be proposed. Phytocannabinoid-terpenoid synergy, if proven, increases the likelihood that an extensive pipeline of new therapeutic products is possible from this venerable plant. http

  13. Synergy between rhinacanthins from Rhinacanthus nasutus in inhibition against mosquito cytochrome P450 enzymes.

    PubMed

    Kotewong, Rattanawadee; Pouyfung, Phisit; Duangkaew, Panida; Prasopthum, Aruna; Rongnoparut, Pornpimol

    2015-07-01

    The cytochrome P450 monooxygenases play a major role in insecticide detoxification and become a target for development of insecticide synergists. In this study, a collection of rhinacanthins (rhinacanthin-D, -E, -G, -N, -Q, and -H/I) purified from Rhinacanthus nasutus, in addition to previously purified rhinacanthin-B and -C, were isolated. These compounds displayed various degrees of inhibition against benzyloxyresorufin-O-debenzylation mediated by CYP6AA3 and CYP6P7 which were implicated in pyrethroid resistance in Anopheles minimus malaria vector. Inhibition modes and kinetics were determined for each of rhinacanthins. Cell-based inhibition assays by rhinacanthins employing 3-(4, 5-dimethylthiazol-2-y-l)-2, 5-diphenyltetrazolium bromide (MTT) cytotoxicity test were explored their synergistic effects with cypermethrin toxicity on CYP6AA3- and CYP6P7-expressing Spodoptera frugiperda (Sf9) cells. Rhinacanthin-B, -D, -E, -G, and -N exhibited mechanism-based inhibition against CYP6AA3, an indication of irreversible inhibition, while rhinacanthin-B, -D, -G, and -N were mechanism-based inhibitors of CYP6P7. There was structure-function relationship of these rhinacanthins in inhibition effects against both enzymes. In vitro enzymatic inhibition assays revealed that there were synergistic interactions among rhinacanthins, except rhinacanthin-B and -Q, in inhibition against both enzymes. These rhinacanthins exerted synergism with cypermethrin toxicity on Sf9 cells expressing each of the two P450 enzymes via P450 inhibition and in addition could interact in synergy to further increase cypermethrin toxicity. The inhibition potentials, synergy among rhinacanthins in inhibition against the P450 detoxification enzymes, and synergism with cypermethrin toxicity of the R. nasutus constituents of reported herein could be beneficial to implement effective resistance management of mosquito vector control. PMID:25869958

  14. In-Depth Analysis Shows Synergy between Erlotinib and miR-34a

    PubMed Central

    Zhao, Jane; Kelnar, Kevin; Bader, Andreas G.

    2014-01-01

    Tyrosine kinase inhibitors directed against epidermal growth factor receptor (EGFR-TKI), such as erlotinib, are effective in a limited fraction of non-small cell lung cancer (NSCLC). However, the majority of NSCLC and other cancer types remain resistant. Therapeutic miRNA mimics modeled after endogenous tumor suppressor miRNAs inhibit tumor growth by repressing multiple oncogenes at once and, therefore, may be used to augment drug sensitivity. Here, we investigated the relationship of miR-34a and erlotinib and determined the therapeutic activity of the combination in NSCLC cells with primary and acquired erlotinib resistance. The drug combination was also tested in a panel of hepatocellular carcinoma cells (HCC), a cancer type known to be refractory to erlotinib. Using multiple analytical approaches, drug-induced inhibition of cancer cell proliferation was determined to reveal additive, antagonistic or synergistic effects. Our data show a strong synergistic interaction between erlotinib and miR-34a mimics in all cancer cells tested. Synergy was observed across a range of different dose levels and drug ratios, reducing IC50 dose requirements for erlotinib and miR-34a by up to 46-fold and 13-fold, respectively. Maximal synergy was detected at dosages that provide a high level of cancer cell inhibition beyond the one that is induced by the single agents alone and, thus, is of clinical relevance. The data suggest that a majority of NSCLC and other cancers previously not suited for erlotinib may prove sensitive to the drug when used in combination with a miR-34a-based therapy. PMID:24551227

  15. Atomic-Structural Synergy for Catalytic CO Oxidation over Palladium-Nickel Nanoalloys

    SciTech Connect

    Shan, Shiyao; Petkov, Valeri; Yang, Lefu; Luo, Jin; Joseph, Pharrah; Mayzel, Dina; Prasai, Binay; Wang, Lingyan; Engelhard, Mark; Zhong, Chuan-Jian

    2014-05-05

    Alloying palladium (Pd) with other transition metals at the nanoscale has become an important pathway for preparation of low-cost, highly active and stable catalysts. However, the lack of understanding of how the alloying phase state, chemical composition and atomic-scale structure of the alloys at the nanoscale influence their catalytic activity impedes the rational design of Pd-nanoalloy catalysts. This work addresses this challenge by a novel approach to investigating the catalytic oxidation of carbon monoxide (CO) over palladium–nickel (PdNi) nanoalloys with well-defined bimetallic composition, which reveals a remarkable maximal catalytic activity at Pd:Ni ratio of ~50:50. Key to understanding the structural-catalytic synergy is the use of high-energy synchrotron X-ray diffraction coupled to atomic pair distribution function (HE-XRD/PDF) analysis to probe the atomic structure of PdNi nanoalloys under controlled thermochemical treatments and CO reaction conditions. Three-dimensional (3D) models of the atomic structure of the nanoalloy particles were generated by reverse Monte Carlo simulations (RMC) guided by the experimental HE-XRD/PDF data. Structural details of the PdNi nanoalloys were extracted from the respective 3D models and compared with the measured catalytic properties. The comparison revealed a strong correlation between the phase state, chemical composition and atomic-scale structure of PdNi nanoalloys and their catalytic activity for CO oxidation. This correlation is further substantiated by analyzing the first atomic neighbor distances and coordination numbers inside the nanoalloy particles and at their surfaces. These findings have provided new insights into the structural synergy of nanoalloy catalysts by controlling the phase state, composition and atomic structure, complementing findings of traditional density functional theory studies.

  16. Atomic-Structural Synergy for Catalytic CO Oxidation over Palladium-Nickel Nanoalloys

    SciTech Connect

    Shan, Shiyao; Petkov, Valeri; Yang, Lefu; Luo, Jin; Joseph, Pharrah; Mayzel, Dina; Prasai, Binay; Wang, Lingyan; Engelhard, Mark H.; Zhong, Chuan-Jian

    2014-05-05

    Alloying palladium (Pd) with other transition metals at the nanoscale has become an important pathway for preparation of low-cost, highly-active and stable catalysts. However the lack of understanding of how the alloying phase state, chemical composition and atomic-scale structure of the alloys at the nanoscale influence their catalytic activity impedes the rational design of Pd-nanoalloy catalysts. This work addresses this challenge by a novel approach to investigating the catalytic oxidation of carbon monoxide (CO) over palladium-nickel (PdNi) nanoalloys with well-defined bimetallic composition, which reveals a remarkable a maximal catalytic activity at Pd:Ni ratio of ~50:50. Key to understanding the structural-catalytic synergy is the use of high-energy synchrotron X-ray diffraction coupled to atomic pair distribution function (HE-XRD/PDF) analysis to probe the atomic structure of PdNi nanoalloys under controlled thermochemical treatments and CO reaction conditions. Three-dimensional (3D) models of the atomic structure of the nanoalloy particles were generated by reverse Monte Carlo simulations (RMC) guided by the experimental HE-XRD/PDF data. Structural details of the PdNi nanoalloys were extracted from the respective 3D models and compared with the measured catalytic properties. The comparison revealed a strong correlation between the phase state, chemical composition and atomic-scale structure of PdNi nanoalloys and their catalytic activity for CO oxidation. This correlation is further substantiated by analyzing the first atomic neighbor distances and coordination numbers inside the nanoalloy particles and at their surfaces. These findings have provided new insights into the structural synergy of nanoalloy catalysts by controlling the phase state, composition and atomic structure, complementing findings of traditional density functional theory studies.

  17. Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects

    PubMed Central

    Russo, Ethan B

    2011-01-01

    Tetrahydrocannabinol (THC) has been the primary focus of cannabis research since 1964, when Raphael Mechoulam isolated and synthesized it. More recently, the synergistic contributions of cannabidiol to cannabis pharmacology and analgesia have been scientifically demonstrated. Other phytocannabinoids, including tetrahydrocannabivarin, cannabigerol and cannabichromene, exert additional effects of therapeutic interest. Innovative conventional plant breeding has yielded cannabis chemotypes expressing high titres of each component for future study. This review will explore another echelon of phytotherapeutic agents, the cannabis terpenoids: limonene, myrcene, α-pinene, linalool, β-caryophyllene, caryophyllene oxide, nerolidol and phytol. Terpenoids share a precursor with phytocannabinoids, and are all flavour and fragrance components common to human diets that have been designated Generally Recognized as Safe by the US Food and Drug Administration and other regulatory agencies. Terpenoids are quite potent, and affect animal and even human behaviour when inhaled from ambient air at serum levels in the single digits ng·mL−1. They display unique therapeutic effects that may contribute meaningfully to the entourage effects of cannabis-based medicinal extracts. Particular focus will be placed on phytocannabinoid-terpenoid interactions that could produce synergy with respect to treatment of pain, inflammation, depression, anxiety, addiction, epilepsy, cancer, fungal and bacterial infections (including methicillin-resistant Staphylococcus aureus). Scientific evidence is presented for non-cannabinoid plant components as putative antidotes to intoxicating effects of THC that could increase its therapeutic index. Methods for investigating entourage effects in future experiments will be proposed. Phytocannabinoid-terpenoid synergy, if proven, increases the likelihood that an extensive pipeline of new therapeutic products is possible from this venerable plant. LINKED ARTICLES

  18. Synergy between acid and endotoxin in an experimental model of aspiration-related lung injury progression.

    PubMed

    Tetenev, Konstantin; Cloutier, Mary E; von Reyn, Jessica A; Ather, Jennifer L; Candon, James; Allen, Gilman B

    2015-11-15

    Aspiration is a common cause of lung injury, but it is unclear why some cases are self-limited while others progress to acute respiratory distress syndrome (ARDS). Sporadic exposure to more than one insult could account for this variable progression. We investigated whether synergy between airway acid and endotoxin (LPS) amplifies injury severity in mice and whether LPS levels in human patients could corroborate our experimental findings. C57BL/6 mice aspirated acid (pH 1.3) or normal saline (NS), followed by LPS aerosol or nothing. Bronchoalveolar lavage fluid (BALF) was obtained 2 to 49 h later. Mice were injected with FITC-dextran 25 h after aspiration and connected to a ventilator, and lung elastance (H) measured periodically following deep inflation (DI). Endotracheal and gastric aspirates were also collected from patients in the intensive care unit and assayed for pH and LPS. Lung instability (ΔH following DI) and pressure-volume hysteresis in acid- or LPS-exposed mice was greater than in controls but markedly greater in the combined acid/LPS group. BALF neutrophils, cytokines, protein, and FITC-dextran in the acid/LPS mice were geometrically higher than all other groups. BALF from acid-only mice markedly amplified LPS-induced TNF-α production in cultured macrophages. Human subjects had variable endotracheal LPS levels with the highest burden in those at higher risk of aspiration. Acid aspiration amplifies LPS signaling in mice to disrupt barrier function and lung mechanics in synergy. High variation in airway LPS and greater airway LPS burden in patients at higher risk of aspiration could help explain the sporadic progression of aspiration to ARDS. PMID:26408552

  19. Synergy Between Experiments and Simulations in Laser and Beam-Driven Plasma Acceleration and Light Sources

    NASA Astrophysics Data System (ADS)

    Mori, Warren B.

    2015-11-01

    Computer simulations have been an integral part of plasma physics research since the early 1960s. Initially, they provided the ability to confirm and test linear and nonlinear theories in one-dimension. As simulation capabilities and computational power improved, then simulations were also used to test new ideas and applications of plasmas in multi-dimensions. As progress continued, simulations were also used to model experiments. Today computer simulations of plasmas are ubiquitously used to test new theories, understand complicated nonlinear phenomenon, model the full temporal and spatial scale of experiments, simulate parameters beyond the reach of current experiments, and test the performance of new devices before large capital expenditures are made to build them. In this talk I review the progress in simulations in a particular area of plasma physics: plasma based acceleration (PBA). In PBA a short laser pulse or particle beam propagates through long regions of plasma creating plasma wave wakefields on which electrons or positrons surf to high energies. In some cases the wakefields are highly nonlinear, involve three-dimensional effects, and the trajectories of plasma particles cross making it essential that fully kinetic and three-dimensional models are used. I will show how particle-in-cell (PIC) simulations were initially used to propose the basic idea of PBA in one dimension. I will review some of the dramatic progress in the experimental demonstration of PBA and show how this progress was dramatically helped by a synergy between experiments and full-scale multi-dimensional PIC simulations. This will include a review of how the capability of PIC simulation tools has improved. I will also touch on some recent progress on improvements to PIC simulations of PBA and discuss how these improvements may push the synergy further towards real time steering of experiments and start to end modeling of key components of a future linear collider or XFEL based on PBA

  20. Cellulase-Xylanase Synergy in Designer Cellulosomes for Enhanced Degradation of a Complex Cellulosic Substrate

    PubMed Central

    Moraïs, Sarah; Barak, Yoav; Caspi, Jonathan; Hadar, Yitzhak; Lamed, Raphael; Shoham, Yuval; Wilson, David B.; Bayer, Edward A.

    2010-01-01

    Designer cellulosomes are precision-engineered multienzyme complexes in which the molecular architecture and enzyme content are exquisitely controlled. This system was used to examine enzyme cooperation for improved synergy among Thermobifida fusca glycoside hydrolases. Two T. fusca cellulases, Cel48A exoglucanase and Cel5A endoglucanase, and two T. fusca xylanases, endoxylanases Xyn10B and Xyn11A, were selected as enzymatic components of a mixed cellulase/xylanase-containing designer cellulosome. The resultant mixed multienzyme complex was fabricated on a single scaffoldin subunit bearing all four enzymes. Conversion of T. fusca enzymes to the cellulosomal mode followed by their subsequent incorporation into a tetravalent cellulosome led to assemblies with enhanced activity (~2.4-fold) on wheat straw as a complex cellulosic substrate. The enhanced synergy was caused by the proximity of the enzymes on the complex compared to the free-enzyme systems. The hydrolytic properties of the tetravalent designer cellulosome were compared with the combined action of two separate divalent cellulase- and xylanase-containing cellulosomes. Significantly, the tetravalent designer cellulosome system exhibited an ~2-fold enhancement in enzymatic activity compared to the activity of the mixture of two distinct divalent scaffoldin-borne enzymes. These results provide additional evidence that close proximity between cellulases and xylanases is key to the observed concerted degradation of the complex cellulosic substrate in which the integrated enzymes complement each other by promoting access to the relevant polysaccharide components of the substrate. The data demonstrate that cooperation among xylanases and cellulases can be augmented by their integration into a single designer cellulosome. PMID:21157512

  1. Hybrid radiator cooling system

    DOEpatents

    France, David M.; Smith, David S.; Yu, Wenhua; Routbort, Jules L.

    2016-03-15

    A method and hybrid radiator-cooling apparatus for implementing enhanced radiator-cooling are provided. The hybrid radiator-cooling apparatus includes an air-side finned surface for air cooling; an elongated vertically extending surface extending outwardly from the air-side finned surface on a downstream air-side of the hybrid radiator; and a water supply for selectively providing evaporative cooling with water flow by gravity on the elongated vertically extending surface.

  2. Managing hybrid marketing systems.

    PubMed

    Moriarty, R T; Moran, U

    1990-01-01

    As competition increases and costs become critical, companies that once went to market only one way are adding new channels and using new methods - creating hybrid marketing systems. These hybrid marketing systems hold the promise of greater coverage and reduced costs. But they are also hard to manage; they inevitably raise questions of conflict and control: conflict because marketing units compete for customers; control because new indirect channels are less subject to management authority. Hard as they are to manage, however, hybrid marketing systems promise to become the dominant design, replacing the "purebred" channel strategy in all kinds of businesses. The trick to managing the hybrid is to analyze tasks and channels within and across a marketing system. A map - the hybrid grid - can help managers make sense of their hybrid system. What the chart reveals is that channels are not the basic building blocks of a marketing system; marketing tasks are. The hybrid grid forces managers to consider various combinations of channels and tasks that will optimize both cost and coverage. Managing conflict is also an important element of a successful hybrid system. Managers should first acknowledge the inevitability of conflict. Then they should move to bound it by creating guidelines that spell out which customers to serve through which methods. Finally, a marketing and sales productivity (MSP) system, consisting of a central marketing database, can act as the central nervous system of a hybrid marketing system, helping managers create customized channels and service for specific customer segments. PMID:10107959

  3. Hybridization facilitates evolutionary rescue

    PubMed Central

    Stelkens, Rike B; Brockhurst, Michael A; Hurst, Gregory D D; Greig, Duncan

    2014-01-01

    The resilience of populations to rapid environmental degradation is a major concern for biodiversity conservation. When environments deteriorate to lethal levels, species must evolve to adapt to the new conditions to avoid extinction. Here, we test the hypothesis that evolutionary rescue may be enabled by hybridization, because hybridization increases genetic variability. Using experimental evolution, we show that interspecific hybrid populations of Saccharomyces yeast adapt to grow in more highly degraded environments than intraspecific and parental crosses, resulting in survival rates far exceeding those of their ancestors. We conclude that hybridization can increase evolutionary responsiveness and that taxa able to exchange genes with distant relatives may better survive rapid environmental change. PMID:25558281

  4. From hybrid swarms to swarms of hybrids

    USGS Publications Warehouse

    Stohlgren, Thomas J.; Szalanski, Allen L; Gaskin, John F.; Young, Nicholas E.; West, Amanda; Jarnevich, Catherine S.; Tripodi, Amber

    2015-01-01

    Science has shown that the introgression or hybridization of modern humans (Homo sapiens) with Neanderthals up to 40,000 YBP may have led to the swarm of modern humans on earth. However, there is little doubt that modern trade and transportation in support of the humans has continued to introduce additional species, genotypes, and hybrids to every country on the globe. We assessed the utility of species distributions modeling of genotypes to assess the risk of current and future invaders. We evaluated 93 locations of the genus Tamarix for which genetic data were available. Maxent models of habitat suitability showed that the hybrid, T. ramosissima x T. chinensis, was slightly greater than the parent taxa (AUCs > 0.83). General linear models of Africanized honey bees, a hybrid cross of Tanzanian Apis mellifera scutellata and a variety of European honey bee including A. m. ligustica, showed that the Africanized bees (AUC = 0.81) may be displacing European honey bees (AUC > 0.76) over large areas of the southwestern U.S. More important, Maxent modeling of sub-populations (A1 and A26 mitotypes based on mDNA) could be accurately modeled (AUC > 0.9), and they responded differently to environmental drivers. This suggests that rapid evolutionary change may be underway in the Africanized bees, allowing the bees to spread into new areas and extending their total range. Protecting native species and ecosystems may benefit from risk maps of harmful invasive species, hybrids, and genotypes.

  5. Modeling of Synergy Between 4th and 6th Harmonic Absorptions of Fast Waves on Injected Beams in DIII-D Tokamak

    SciTech Connect

    Choi, M.; Pinsker, R. I.; Chan, V. S.; Muscatello, C. M.; Jaeger, E. F.

    2011-12-23

    In recent moderate to high harmonic fast wave heating and current drive experiments in DIII-D, a synergy effect was observed when the 6{sup th} harmonic 90 MHz fast wave power is applied to the plasma preheated by neutral beams and the 4{sup th} harmonic 60 MHz fast wave. In this paper, we investigate how the synergy can occur using ORBIT-RF coupled with AORSA. Preliminary simulations suggest that damping of 4{sup th} harmonic FW on beam ions accelerates them above the injection energy, which may allow significant damping of 6{sup th} harmonic FW on beam ion tails to produce synergy.

  6. Hybrid baryons [alpha].

    SciTech Connect

    Page, P. R.

    2002-01-01

    The authors review the status of hybrid baryons. The only known way to study hybrids rigorously is via excited adiabatic potentials. Hybrids can be modeled by both the bag and flux tube models. The low lying hybrid baryon is N 1/2{sup +} with a mass of 1.5 - 1.8 GeV. Hybrid baryons can be produced in the glue rich processes of diffractive {gamma}N and {pi}N production, {Psi} decays and p{bar p} annihilation. We review the current status of research on three quarks with a gluonic excitation, called a hybrid baryon. The excitation is not an orbital or radial excitation between the quarks. Hybrid baryons have also been reviewed elsewhere. The Mercedes-Benz logl in Figure 1 indicates two possible views of the confining interaction of three quarks, an essential issue in the study of hybrid baryons. In the logo the three points where the Y shape meets the boundary circle should be identified with the three quarks. There are two possibilities fo rthe interaction of the quarks: (1) a pairwise interaction of the quarks represented by the circle, or (2) a Y shaped interaction between the quarks, represented by the Y-shape in the logo.

  7. Hybrid Rocket Motor Test

    NASA Technical Reports Server (NTRS)

    1994-01-01

    A 10,000-pound thrust hybrid rocket motor is tested at Stennis Space Center's E-1 test facility. A hybrid rocket motor is a cross between a solid rocket and a liquid-fueled engine. It uses environmentally safe solid fuel and liquid oxygen.

  8. Hybrid reactors. [Fuel cycle

    SciTech Connect

    Moir, R.W.

    1980-09-09

    The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of /sup 233/U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW.m/sup -2/, and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are usually rapid.

  9. Hybrid rocket performance

    NASA Astrophysics Data System (ADS)

    Frederick, Robert A., Jr.

    1992-12-01

    A hybrid rocket is a system consisting of a solid fuel grain and a gaseous or liquid oxidizer. Figure 1 shows three popular hybrid propulsion cycles that are under current consideration. NASA MSFC has teamed with industry to test two hybrid propulsion systems that will allow scaling to motors of potential interest for Titan and Atlas systems, as well as encompassing the range of interest for SEI lunar ascent stages and National Launch System Cargo Transfer Vehicle (NLS CTV) and NLS deorbit systems. Hybrid systems also offer advantages as moderate-cost, environmentally acceptable propulsion system. The objective of this work was to recommend a performance prediction methodology for hybrid rocket motors. The scope included completion of: a literature review, a general methodology, and a simplified performance model.

  10. Hybrid rocket performance

    NASA Technical Reports Server (NTRS)

    Frederick, Robert A., Jr.

    1992-01-01

    A hybrid rocket is a system consisting of a solid fuel grain and a gaseous or liquid oxidizer. Figure 1 shows three popular hybrid propulsion cycles that are under current consideration. NASA MSFC has teamed with industry to test two hybrid propulsion systems that will allow scaling to motors of potential interest for Titan and Atlas systems, as well as encompassing the range of interest for SEI lunar ascent stages and National Launch System Cargo Transfer Vehicle (NLS CTV) and NLS deorbit systems. Hybrid systems also offer advantages as moderate-cost, environmentally acceptable propulsion system. The objective of this work was to recommend a performance prediction methodology for hybrid rocket motors. The scope included completion of: a literature review, a general methodology, and a simplified performance model.

  11. Hybrid baryons in QCD

    SciTech Connect

    Dudek, Jozef J.; Edwards, Robert G.

    2012-03-21

    In this study, we present the first comprehensive study of hybrid baryons using lattice QCD methods. Using a large basis of composite QCD interpolating fields we extract an extensive spectrum of baryon states and isolate those of hybrid character using their relatively large overlap onto operators which sample gluonic excitations. We consider the spectrum of Nucleon and Delta states at several quark masses finding a set of positive parity hybrid baryons with quantum numbers $N_{1/2^+},\\,N_{1/2^+},\\,N_{3/2^+},\\, N_{3/2^+},\\,N_{5/2^+},\\,$ and $\\Delta_{1/2^+},\\, \\Delta_{3/2^+}$ at an energy scale above the first band of `conventional' excited positive parity baryons. This pattern of states is compatible with a color octet gluonic excitation having $J^{P}=1^{+}$ as previously reported in the hybrid meson sector and with a comparable energy scale for the excitation, suggesting a common bound-state construction for hybrid mesons and baryons.

  12. Hybrid propulsion technology program

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Technology was identified which will enable application of hybrid propulsion to manned and unmanned space launch vehicles. Two design concepts are proposed. The first is a hybrid propulsion system using the classical method of regression (classical hybrid) resulting from the flow of oxidizer across a fuel grain surface. The second system uses a self-sustaining gas generator (gas generator hybrid) to produce a fuel rich exhaust that was mixed with oxidizer in a separate combustor. Both systems offer cost and reliability improvement over the existing solid rocket booster and proposed liquid boosters. The designs were evaluated using life cycle cost and reliability. The program consisted of: (1) identification and evaluation of candidate oxidizers and fuels; (2) preliminary evaluation of booster design concepts; (3) preparation of a detailed point design including life cycle costs and reliability analyses; (4) identification of those hybrid specific technologies needing improvement; and (5) preperation of a technology acquisition plan and large scale demonstration plan.

  13. Explorations into the Synergy Between Faith, Health, and Health-Care Among Black Baptists

    PubMed Central

    Maclin, Sandy D.

    2013-01-01

    Background U.S. health disparities are documented by race/ethnic, socioeconomic, gender, and geographic demographics. Since federal health record keeping began, regardless of other demographic factors, Black people continue to record statistical significant disparities. The complementary and alternative medicine (CAM) domain of mind-body medicine provides a method and language to assess the metaphysical constructs of faith, spirituality and religion and their influence on health and healthcare practices. Explorations into the synergy between faith, health and healthcare among a convenient sample of Black Baptist conventioneers provides an opportunity to better understand if and how faith can be used to enhance the health and wellbeing of Black people. Methodology In 2005 a convenience sample of 2,500 Black persons among 10,000 Joint Baptist conventioneers participated in the study; 1,827 completed and returned an 80 item questionnaire. 500 surveys were lost due to computer malfunctions. Survey results covered: demographic, health/safety, health care, and faith/religion/health. Results 58.6% of respondents were women; 61% were married. Most (66.2%) reported good health and few were told by their physician they had a chronic disease. 33.5% never talk to their pastor about health problems or (42.7%) physician visits. Mental health responses: (98.7%) get along well with others; (93.6%) were satisfied with life; (92.8%) feel good about themselves; and (97.6%) were in good spirits most times. Many were in social organizations (40.6%). 96.1% felt religion was very important in their life; 91% thought religion affects physical/mental health; and 89.1% believed faith affects mental/physical health. 95.7% believe faith can change a health crisis. Most described religion and faith differently. Discussion The Black Church has history in social justice connected to community health. Responses to religion/faith affirm the interconnectedness of the synergy between faith

  14. Developing a synergy algorithm for land surface temperature: the SEN4LST project

    NASA Astrophysics Data System (ADS)

    Sobrino, Jose A.; Jimenez, Juan C.; Ghent, Darren J.

    2013-04-01

    Land surface Temperature (LST) is one of the key parameters in the physics of land-surface processes on regional and global scales, combining the results of all surface-atmosphere interactions and energy fluxes between the surface and the atmosphere. An adequate characterization of LST distribution and its temporal evolution requires measurements with detailed spatial and temporal frequencies. With the advent of the Sentinel 2 (S2) and 3 (S3) series of satellites a unique opportunity exists to go beyond the current state of the art of single instrument algorithms. The Synergistic Use of The Sentinel Missions For Estimating And Monitoring Land Surface Temperature (SEN4LST) project aims at developing techniques to fully utilize synergy between S2 and S3 instruments in order to improve LST retrievals. In the framework of the SEN4LST project, three LST retrieval algorithms were proposed using the thermal infrared bands of the Sea and Land Surface Temperature Retrieval (SLSTR) instrument on board the S3 platform: split-window (SW), dual-angle (DA) and a combined algorithm using both split-window and dual-angle techniques (SW-DA). One of the objectives of the project is to select the best algorithm to generate LST products from the synergy between S2/S3 instruments. In this sense, validation is a critical step in the selection process for the best performing candidate algorithm. A unique match-up database constructed at University of Leicester (UoL) of in situ observations from over twenty ground stations and corresponding brightness temperature (BT) and LST match-ups from multi-sensor overpasses is utilised for validating the candidate algorithms. Furthermore, their performance is also evaluated against the standard ESA LST product and the enhanced offline UoL LST product. In addition, a simulation dataset is constructed using 17 synthetic images of LST and the radiative transfer model MODTRAN carried under 66 different atmospheric conditions. Each candidate LST

  15. Soil Moisture Retrieval from Active/Passive Microwave Observation Synergy Using a Neural Network Approach

    NASA Astrophysics Data System (ADS)

    Kolassa, J.; Gentine, P.; Aires, F.; Prigent, C.

    2014-12-01

    In November 2014 NASA will launch the Soil Moisture Active/Passive (SMAP) mission carrying an L-band radiometer and radar sensor to observe surface soil moisture globally. This new type of instrument requires the development of innovative retrieval algorithms that are able to account for the different surface contributions to the satellite signal and at the same time can optimally exploit the synergy of active and passive microwave data. In this study, a neural network (NN) based retrieval algorithm has been developed using the example of active microwave observations from ASCAT and passive microwave observations from AMSR-E. In a first step, different preprocessing techniques, aiming to highlight the various contributions to the satellite signal, have been investigated. It was found that in particular for the passive microwave observations, the use of multiple frequencies and preprocessing steps could help the retrieval to disentangle the effects of soil moisture, vegetation and surface temperature. A spectral analysis investigated the temporal patterns in the satellite observations and thus assessed which soil moisture temporal variations could realistically be retrieved. The preprocessed data was then used in a NN based retrieval to estimate daily volumetric surface soil moisture at the global scale for the period 2002-2013. It could be shown that the synergy of data from the two sensors yielded a significant improvement of the retrieval performance demonstrating the benefit of multi-sensor approaches as proposed for SMAP. A comparison with a more traditional retrieval product merging approach furthermore showed that the NN technique is better able to exploit the complementarity of information provided by active and passive sensors. The soil moisture retrieval product was evaluated in the spatial, temporal and frequency domain against retrieved soil moisture from WACMOS and SMOS, modeled fields from ERA-interim/Land and in situ observations from the

  16. Imaging doses from the Elekta Synergy X-ray cone beam CT system.

    PubMed

    Amer, A; Marchant, T; Sykes, J; Czajka, J; Moore, C

    2007-06-01

    The Elekta Synergy is a radiotherapy treatment machine with integrated kilovoltage (kV) X-ray imaging system capable of producing cone beam CT (CBCT) images of the patient in the treatment position. The aim of this study is to assess the additional imaging dose. Cone beam CT dose index (CBDI) is introduced and measured inside standard CTDI phantoms for several sites (head: 100 kV, 38 mAs, lung: 120 kV, 152 mAs and pelvis: 130 kV, 456 mAs). The measured weighted doses were compared with thermoluminescent dosimeter (TLD) measurements at various locations in a Rando phantom and at patients' surfaces. The measured CBDIs in-air at the isocentre were 9.2 mGy 100 mAs(-1), 7.3 mGy 100 mAs(-1) and 5.3 mGy 100 mAs(-1) for 130 kV, 120 kV and 100 kV, respectively. The body phantom weighted CBDI were 5.5 mGy 100 mAs(-1) and 3.8 mGy 100 mAs(-1 )for 130 kV and 120 kV. The head phantom weighted CBDI was 4.3 mGy 100 mAs(-1) for 100 kV. The weighted doses for the Christie Hospital CBCT imaging techniques were 1.6 mGy, 6 mGy and 22 mGy for the head, lung and pelvis. The measured CBDIs were used to estimate the total effective dose for the Synergy system using the ImPACT CT Patient Dosimetry Calculator. Measured CBCT doses using the Christie Hospital protocols are low for head and lung scans whether compared with electronic portal imaging (EPI), commonly used for treatment verification, or single and multiple slice CT. For the pelvis, doses are similar to EPI but higher than CT. Repeated use of CBCT for treatment verification is likely and hence the total patient dose needs to be carefully considered. It is important to consider further development of low dose CBCT techniques to keep additional doses as low as reasonably practicable. PMID:17684077

  17. Drug Synergy of Tenofovir and Nanoparticle-Based Antiretrovirals for HIV Prophylaxis

    PubMed Central

    Chaowanachan, Thanyanan; Krogstad, Emily; Ball, Cameron; Woodrow, Kim A.

    2013-01-01

    Background The use of drug combinations has revolutionized the treatment of HIV but there is no equivalent combination product that exists for prevention, particularly for topical HIV prevention. Strategies to combine chemically incompatible agents may facilitate the discovery of unique drug-drug activities, particularly unexplored combination drug synergy. We fabricated two types of nanoparticles, each loaded with a single antiretroviral (ARV) that acts on a specific step of the viral replication cycle. Here we show unique combination drug activities mediated by our polymeric delivery systems when combined with free tenofovir (TFV). Methodology/Principal Findings Biodegradable poly(lactide-co-glycolide) nanoparticles loaded with efavirenz (NP-EFV) or saquinavir (NP-SQV) were individually prepared by emulsion or nanoprecipitation techniques. Nanoparticles had reproducible size (d ∼200 nm) and zeta potential (-25 mV). The drug loading of the nanoparticles was approximately 7% (w/w). NP-EFV and NP-SQV were nontoxic to TZM-bl cells and ectocervical explants. Both NP-EFV and NP-SQV exhibited potent protection against HIV-1 BaL infection in vitro. The HIV inhibitory effect of nanoparticle formulated ARVs showed up to a 50-fold reduction in the 50% inhibitory concentration (IC50) compared to free drug. To quantify the activity arising from delivery of drug combinations, we calculated combination indices (CI) according to the median-effect principle. NP-EFV combined with free TFV demonstrated strong synergistic effects (CI50 = 0.07) at a 1∶50 ratio of IC50 values and additive effects (CI50 = 1.05) at a 1∶1 ratio of IC50 values. TFV combined with NP-SQV at a 1∶1 ratio of IC50 values also showed strong synergy (CI50 = 0.07). Conclusions ARVs with different physicochemical properties can be encapsulated individually into nanoparticles to potently inhibit HIV. Our findings demonstrate for the first time that combining TFV with either NP-EFV or NP

  18. Hybrid vigour in dogs?

    PubMed

    Nicholas, Frank W; Arnott, Elizabeth R; McGreevy, Paul D

    2016-08-01

    Evidence from other species justifies the hypotheses that useful hybrid vigour occurs in dogs and that it can be exploited for improved health, welfare and fitness for purpose. Unfortunately, most of the relevant published canine studies do not provide estimates of actual hybrid vigour because of inadequate specification of the parentage of mixed-bred dogs. To our knowledge, only three published studies have shed any light on actual hybrid vigour in dogs. There are two reports of actual hybrid vigour between Labrador and Golden retrievers, the first ranging from +2.5% to -6.0% for components of a standardised applied-stimulus behavioural test, and the second being at least +12.4% for chance of graduating as a guide dog. The third study provides a minimum estimate of negative actual hybrid vigour: crossbreds between Labrador retrievers and poodles had a higher prevalence of multifocal retinal dysplasia than the average prevalence in their purebred parent breeds. The lack of estimates of actual hybrid vigour can be overcome by including the exact nature of the cross (e.g. F1, F2 or backcross) and their purebred parental breeds in the specification of mixed-bred dogs. Even if only F1 crossbreds can be categorised, this change would enable researchers to conduct substantial investigations to determine whether hybrid vigour has any utility for dog breeding. PMID:27387730

  19. Failure of time-kill synergy studies using subinhibitory antimicrobial concentrations to predict in vivo antagonism of cephalosporin-rifampin combinations against Staphylococcus aureus.

    PubMed Central

    Brandt, C M; Rouse, M S; Tallan, B M; Wilson, W R; Steckelberg, J M

    1994-01-01

    Results of in vitro time-kill synergy studies using subinhibitory, inhibitory, or suprainhibitory concentrations of bactericidal agents were compared with treatment outcomes of experimental infective endocarditis due to a methicillin-susceptible strain of Staphylococcus aureus. For rifampin-cephalosporin combinations, in vitro synergy testing using recommended fractions of the MIC failed to predict antagonism in vivo while concentrations above the MIC corresponded with antagonism in vivo. PMID:7811044

  20. β-Lactam combinations with daptomycin provide synergy against vancomycin-resistant Enterococcus faecalis and Enterococcus faecium

    PubMed Central

    Smith, Jordan R.; Barber, Katie E.; Raut, Animesh; Aboutaleb, Mostafa; Sakoulas, George; Rybak, Michael J.

    2015-01-01

    Objectives Enterococcus faecalis (Efc) and Enterococcus faecium (Efm) are frequently resistant to vancomycin and β-lactams (BLs). In vitro data suggest synergy between several BLs and glycopeptides or lipopeptides against resistant pathogens. Our objective was to conduct combination MIC and time–kill experiments to evaluate BL synergy with daptomycin against enterococci. Methods Fifteen Efc and 20 Efm strains were evaluated for daptomycin enhancement via combination MICs. Daptomycin MICs were obtained by microdilution in the absence and presence of ceftaroline, ertapenem, cefepime, ceftriaxone, cefotaxime, cefazolin and ampicillin. Two Efc strains (R6981 and R7808) and one isogenic daptomycin-susceptible/daptomycin-non-susceptible Efm pair (8019/5938) were evaluated in time–kill experiments. Daptomycin at 0.5 × MIC was used in combination with BL at biological free concentration. Strain 5938 was evaluated for enhancement of daptomycin binding in fluorescently labelled daptomycin (BoDipy) experiments. Results Ceftaroline reduced daptomycin MIC values the most against all strains. In time–kill experiments, ceftaroline, ertapenem, cefepime, ceftriaxone and ampicillin demonstrated synergy with daptomycin against all strains, cefazolin demonstrated none and cefotaxime demonstrated synergy against only R7808. Bacterial reduction at 24 h was greater for daptomycin + ceftaroline, ertapenem, cefepime, ceftriaxone or ampicillin for all strains compared with any single agent or daptomycin + cefazolin or cefotaxime (P < 0.001). In BoDipy daptomycin experiments, ceftaroline enhanced daptomycin binding most compared with all other agents (P < 0.001). Conclusions The data support the potential use of daptomycin/BL combination therapy in infections caused by VRE. Combination regimens, other than those involving cefazolin and cefotaxime, provide better kill compared with daptomycin alone. Further clinical research involving daptomycin combinations is

  1. Functional Hybrid Materials

    NASA Astrophysics Data System (ADS)

    Gómez-Romero, Pedro; Sanchez, Clément

    2004-04-01

    Functional Hybrid Materials consist of both organic and inorganic components, assembled for the purpose of generating desirable properties and functionalities. The aim is twofold: to bring out or enhance advantageous chemical, electrochemical, magnetic or electronic characteristics and at the same time to reduce or wholly suppress undesirable properties or effects. Another target is the creation of entirely new material behavior. The vast number of hybrid material components available has opened up a wide and diversified field of fascinating research. In this book, a team of highly renowned experts gives an in-depth overview, illustrating the superiority of well-designed hybrid materials and their potential applications.

  2. Hybrid matrix fiber composites

    DOEpatents

    Deteresa, Steven J.; Lyon, Richard E.; Groves, Scott E.

    2003-07-15

    Hybrid matrix fiber composites having enhanced compressive performance as well as enhanced stiffness, toughness and durability suitable for compression-critical applications. The methods for producing the fiber composites using matrix hybridization. The hybrid matrix fiber composites include two chemically or physically bonded matrix materials, whereas the first matrix materials are used to impregnate multi-filament fibers formed into ribbons and the second matrix material is placed around and between the fiber ribbons that are impregnated with the first matrix material and both matrix materials are cured and solidified.

  3. Artificial mismatch hybridization

    DOEpatents

    Guo, Zhen; Smith, Lloyd M.

    1998-01-01

    An improved nucleic acid hybridization process is provided which employs a modified oligonucleotide and improves the ability to discriminate a control nucleic acid target from a variant nucleic acid target containing a sequence variation. The modified probe contains at least one artificial mismatch relative to the control nucleic acid target in addition to any mismatch(es) arising from the sequence variation. The invention has direct and advantageous application to numerous existing hybridization methods, including, applications that employ, for example, the Polymerase Chain Reaction, allele-specific nucleic acid sequencing methods, and diagnostic hybridization methods.

  4. Hybrid electric vehicles TOPTEC

    SciTech Connect

    1994-06-21

    This one-day TOPTEC session began with an overview of hybrid electric vehicle technology. Updates were given on alternative types of energy storage, APU control for low emissions, simulation programs, and industry and government activities. The keynote speech was about battery technology, a key element to the success of hybrids. The TOPEC concluded with a panel discussion on the mission of hybrid electric vehicles, with a perspective from industry and government experts from United States and Canada on their view of the role of this technology.

  5. Towers of hybrid mesons

    SciTech Connect

    Semay, Claude; Buisseret, Fabien; Silvestre-Brac, Bernard

    2009-05-01

    A hybrid meson is a quark-antiquark pair in which, contrary to ordinary mesons, the gluon field is in an excited state. In the framework of constituent models, the interaction potential is assumed to be the energy of an excited string. An approximate, but accurate, analytical solution of the Schroedinger equation with such a potential is presented. When applied to hybrid charmonia and bottomonia, towers of states are predicted in which the masses are a linear function of a harmonic oscillator band number for the quark-antiquark pair. Such a formula could be a reliable guide for the experimental detection of heavy hybrid mesons.

  6. Towards multifunctional agricultural landscapes in Europe: Assessing and governing synergies between food production, biodiversity, and ecosystem services - TALE

    NASA Astrophysics Data System (ADS)

    Volk, Martin; Cord, Anna; Demiguel, Ángel; Holzkämper, Annelie; Kaim, Andrea; Kirchner, Mathias; Lienhoop, Nele; Nieto Romero, Marta; Nitsch, Heike; Rutz, Cordula; Saa, Antonio; Schmid, Erwin; Schönhart, Martin; Schramek, Jörg; Strauch, Michael; Tarquis Alfonso, Ana Maria; van der Zanden, Emma H.; Verburg, Peter; Willaarts, Bárbara; Zarrineh, Nina; Rivas, David; Hagemann, Nina

    2016-04-01

    There is a need to improve our understanding of the synergies between biodiversity, food and energy production and other regulating or cultural ecosystem services (ESS) and the development of technical and policy measures to support these synergies. Procedures to quantify synergies and trade-offs between ESS and biodiversity are considered as promising solutions to close this gap. The BiodivERsA project TALE aims at developing such methodologies in a set of representative European agricultural landscapes in Germany, Switzerland, Austria, The Netherlands and Spain. This will be done by using i) a framework that links process-based, integrated, and statistical models with optimization algorithms, and ii) a set of land use scenarios and land use policies, iii) a systematic stakeholder integration process that allows the incorporation of expert knowledge in all phases of the research project to safeguard that research results are of practical relevance. Moreover, the project not only addresses experts but provides an innovative online learning environment that is accessible also for students and the general public.

  7. Adapting portfolio theory for the evaluation of multiple investments in health with a multiplicative extension for treatment synergies.

    PubMed

    Bridges, J F P; Stewart, M; King, M T; van Gool, K

    2002-01-01

    Portfolio theory is central to the analysis of risk in many areas of economics but is seldom used appropriately in health economics. This contribution examines the use of portfolio theory in the context of cost-effectiveness analysis (CEA). A number of modifications are needed to apply portfolio analysis to the economic evaluation of health care interventions. First, the method of reporting the results of a CEA, and consequently some of the underlying assumptions, needs to be modified. Second, portfolio theory needs to be expressed in terms of effects on individuals aggregated to a population. Finally, one needs to allow for the possibility of synergy between the various health interventions. This paper derives a general formula for a portfolio of health care interventions that allows for synergies between interventions where the population effects are aggregated from individual effects. A number of special cases are also derived to highlight the nature of the formulation of the modified portfolio theory. We conclude that, while modified portfolio theory adds a theoretical foundation to health care evaluations, it may not be operational until estimates of the correlation between interventions are available, and the question of uncertainty is resolved in health care evaluation. Also, while a synergy may be present at the individual level, when aggregated over a large population it may not be significant given the standard assumption of constant returns to scale. PMID:15609117

  8. Effect of Stress on Viral–Bacterial Synergy in Bovine Respiratory Disease: Novel Mechanisms to Regulate Inflammation

    PubMed Central

    Hodgson, P. D.; Aich, P.; Manuja, A.; Hokamp, K.; Roche, F. M.; Brinkman, F. S. L.; Potter, A.; Babiuk, L. A.

    2005-01-01

    The severity of bovine respiratory infections has been linked to a variety of factors, including environmental and nutritional changes, transportation, and social reorganization of weaned calves. Fatal respiratory infections, however, usually occur when a primary viral infection compromises host defences and enhances the severity of a secondary bacterial infection. This viral–bacterial synergy can occur by a number of different mechanisms and disease challenge models have been developed to analyse host responses during these respiratory infections. A primary bovine herpesvirus-1 (BHV-1) respiratory infection followed by a secondary challenge with Mannheimia haemolytica results in fatal bovine respiratory disease (BRD) and host responses to these two pathogens have been studied extensively. We used this disease model to demonstrate that stress significantly altered the viral–bacterial synergy resulting in fatal BRD. Functional genomic analysis revealed that BHV-1 infection enhanced toll-like receptors (TLR) expression and increased pro-inflammatory responses which contribute to the severity of a Mannheimia haemolytica infection. TLRs play a critical role in detecting bacterial infections and inducing pro-inflammatory responses. It is difficult to understand, however, how stress-induced corticosteroids could enhance this form of viral–bacterial synergy. Nuclear translocation of the glucocorticoid receptor activates cell signalling pathways which inhibit both TLR signalling and pro-inflammatory responses. The apparent conundrum between stress-induced corticosteroids and enhanced BRD susceptibility is discussed in terms of present data and previous investigations of stress and respiratory disease. PMID:18629190

  9. Comparative evaluation of three surveillance systems for infectious equine diseases in France and implications for future synergies.

    PubMed

    Amat, J P; Hendrikx, P; Tapprest, J; Leblond, A; Dufour, B

    2015-10-01

    It is necessary to assess surveillance systems for infectious animal diseases to ensure they meet their objectives and provide high-quality health information. Each system is generally dedicated to one disease and often comprises various components. In many animal industries, several surveillance systems are implemented separately even if they are based on similar components. This lack of synergy may prevent optimal surveillance. The purpose of this study was to assess several surveillance systems within the same industry using the semi-quantitative OASIS method and to compare the results of the assessments in order to propose improvements, including future synergies. We have focused on the surveillance of three major equine diseases in France. We have identified the mutual and specific strengths and weaknesses of each surveillance system. Furthermore, the comparative assessment has highlighted many possible synergies that could improve the effectiveness and efficiency of surveillance as a whole, including the implementation of new joint tools or the pooling of existing teams, tools or skills. Our approach is an original application of the OASIS method, which requires minimal financial resources and is not very time-consuming. Such a comparative evaluation could conceivably be applied to other surveillance systems, other industries and other countries. This approach would be especially relevant to enhance the efficiency of surveillance activities when resources are limited. PMID:25712325

  10. Synergy, compatibility, and innovation: merging Lewis acids with stereoselective enamine catalysis.

    PubMed

    Gualandi, Andrea; Mengozzi, Luca; Wilson, Claire M; Cozzi, Pier Giorgio

    2014-04-01

    In recent years there has been an accelerated rate of development in the field of organocatalysis, with asymmetric organocatalysis now reaching full maturity. The invention of new organocatalytic reactions and the exploration of new concepts now appear in tandem with the application of organocatalytic techniques in the synthesis of natural products and active pharmaceutical ingredients (APIs). After a "golden rush" in organocatalysis, researchers are now starting to combine different methods, thereby taking advantage of the significant benefits of synergy. Metals are used in combination with organocatalytic processes, thus reaching complexity that is found in nature, where enzymes take advantage of the presence of certain metals to increase the arsenal of organic transformations available. In this Focus review, we illustrate the possibility of a "happy marriage" between Lewis acids and organocatalytic stereoselective processes. Questions have been raised about the combination of Lewis acids and organocatalysis owing to the presence of water and/or strong bases in these processes. Some Lewis acids have been shown to be compatible with organocatalysis and concepts relating to their use will be illustrated herein. To summarize the fruitful use of Lewis acids in stereoselective organocatalytic processes, we will draw attention to the advantages and selectivity achieved using this method. PMID:24677815

  11. Scaling and optimal synergy: Two principles determining microbial growth in complex media

    NASA Astrophysics Data System (ADS)

    Massucci, Francesco Alessandro; Guimerà, Roger; Nunes Amaral, Luís A.; Sales-Pardo, Marta

    2015-06-01

    High-throughput experimental techniques and bioinformatics tools make it possible to obtain reconstructions of the metabolism of microbial species. Combined with mathematical frameworks such as flux balance analysis, which assumes that nutrients are used so as to maximize growth, these reconstructions enable us to predict microbial growth. Although such predictions are generally accurate, these approaches do not give insights on how different nutrients are used to produce growth, and thus are difficult to generalize to new media or to different organisms. Here, we propose a systems-level phenomenological model of metabolism inspired by the virial expansion. Our model predicts biomass production given the nutrient uptakes and a reduced set of parameters, which can be easily determined experimentally. To validate our model, we test it against in silico simulations and experimental measurements of growth, and find good agreement. From a biological point of view, our model uncovers the impact that individual nutrients and the synergistic interaction between nutrient pairs have on growth, and suggests that we can understand the growth maximization principle as the optimization of nutrient synergies.

  12. Synergy of elastic and inelastic energy loss on ion track formation in SrTiO₃.

    PubMed

    Weber, William J; Zarkadoula, Eva; Pakarinen, Olli H; Sachan, Ritesh; Chisholm, Matthew F; Liu, Peng; Xue, Haizhou; Jin, Ke; Zhang, Yanwen

    2015-01-01

    While the interaction of energetic ions with solids is well known to result in inelastic energy loss to electrons and elastic energy loss to atomic nuclei in the solid, the coupled effects of these energy losses on defect production, nanostructure evolution and phase transformations in ionic and covalently bonded materials are complex and not well understood due to dependencies on electron-electron scattering processes, electron-phonon coupling, localized electronic excitations, diffusivity of charged defects, and solid-state radiolysis. Here we show that a colossal synergy occurs between inelastic energy loss and pre-existing atomic defects created by elastic energy loss in single crystal strontium titanate (SrTiO₃), resulting in the formation of nanometer-sized amorphous tracks, but only in the narrow region with pre-existing defects. These defects locally decrease the electronic and atomic thermal conductivities and increase electron-phonon coupling, which locally increase the intensity of the thermal spike for each ion. This work identifies a major gap in understanding on the role of defects in electronic energy dissipation and electron-phonon coupling; it also provides insights for creating novel interfaces and nanostructures to functionalize thin film structures, including tunable electronic, ionic, magnetic and optical properties. PMID:25578009

  13. Antimicrobial activity of phenolics and glucosinolate hydrolysis products and their synergy with streptomycin against pathogenic bacteria.

    PubMed

    Saavedra, Maria J; Borges, Anabela; Dias, Carla; Aires, Alfredo; Bennett, Richard N; Rosa, Eduardo S; Simões, Manuel

    2010-05-01

    The purpose of the present study was to evaluate the in vitro antibacterial effects of different classes of important and common dietary phytochemicals (5 simple phenolics - tyrosol, gallic acid, caffeic acid, ferulic acid, and chlorogenic acid; chalcone - phloridzin; flavan-3-ol - (-) epicatechin; seco-iridoid - oleuropein glucoside; 3 glucosinolate hydrolysis products - allylisothiocyanate, benzylisothiocyanate and 2-phenylethylisothiocyanate) against Escherichia coli, Pseudomonas aeruginosa, Listeria monocytogenes and Staphylococcus aureus. Another objective of this study was to evaluate the effects of dual combinations of streptomycin with the different phytochemicals on antibacterial activity. A disc diffusion assay was used to evaluate the antibacterial activity of the phytochemicals and 3 standard antibiotics (ciprofloxacin, gentamicin and streptomycin) against the four bacteria. The antimicrobial activity of single compounds and dual combinations (streptomycin-phytochemicals) were quantitatively assessed by measuring the inhibitory halos. The results showed that all of the isothiocyanates had significant antimicrobial activities, while the phenolics were much less efficient. No antimicrobial activity was observed with phloridzin. In general P. aeruginosa was the most sensitive microorganism and L. monocytogenes the most resistant. The application of dual combinations demonstrated synergy between streptomycin and gallic acid, ferulic acid, chlorogenic acid, allylisothiocyanate and 2-phenylethylisothiocyanate against the Gram-negative bacteria. In conclusion, phytochemical products and more specifically the isothiocyanates were effective inhibitors of the in vitro growth of the Gram-negative and Gram-positive pathogenic bacteria. Moreover, they can act synergistically with less efficient antibiotics to control bacterial growth. PMID:20632977

  14. NSAIDs increase survival in the Sandhoff disease mouse: synergy with N-butyldeoxynojirimycin.

    PubMed

    Jeyakumar, Mylvaganam; Smith, David A; Williams, Ian M; Borja, Mario Cortina; Neville, David C A; Butters, Terry D; Dwek, Raymond A; Platt, Frances M

    2004-11-01

    The GM2 gangliosidoses are caused by incomplete catabolism of GM2 ganglioside in the lysosome, leading to progressive storage and a neurodegenerative clinical course. An inflammatory response (microglial activation, macrophage infiltration, oxidative damage) has been found to be a consequence of GM2 storage in the brain, although it remains unclear whether this contributes to pathogenesis or disease progression. In this study, we treated Sandhoff disease mice with nonsteroidal antiinflammatory drugs (indomethacin, aspirin, and ibuprofen) and antioxidants (L-ascorbic acid and alpha-tocopherol acetate). The treated mice lived significantly longer than untreated littermates (12-23%, p <0.0001) and showed a slower rate of disease progression (p <0.001). When aspirin treatment was combined with substrate reduction therapy, synergy resulted (11%, p <0.05) with a maximum improvement of 73% in survival (p <0.00001). This study demonstrates that inflammation contributes to disease progression and identifies antiinflammatory and antioxidant therapies as a potential adjunctive approach to slow the clinical course of this and related disorders. PMID:15505823

  15. An essential role of acetylcholine-glutamate synergy at habenular synapses in nicotine dependence

    PubMed Central

    Frahm, Silke; Antolin-Fontes, Beatriz; Görlich, Andreas; Zander, Johannes-Friedrich; Ahnert-Hilger, Gudrun; Ibañez-Tallon, Ines

    2015-01-01

    A great deal of interest has been focused recently on the habenula and its critical role in aversion, negative-reward and drug dependence. Using a conditional mouse model of the ACh-synthesizing enzyme choline acetyltransferase (Chat), we report that local elimination of acetylcholine (ACh) in medial habenula (MHb) neurons alters glutamate corelease and presynaptic facilitation. Electron microscopy and immuno-isolation analyses revealed colocalization of ACh and glutamate vesicular transporters in synaptic vesicles (SVs) in the central IPN. Glutamate reuptake in SVs prepared from the IPN was increased by ACh, indicating vesicular synergy. Mice lacking CHAT in habenular neurons were insensitive to nicotine-conditioned reward and withdrawal. These data demonstrate that ACh controls the quantal size and release frequency of glutamate at habenular synapses, and suggest that the synergistic functions of ACh and glutamate may be generally important for modulation of cholinergic circuit function and behavior. DOI: http://dx.doi.org/10.7554/eLife.11396.001 PMID:26623516

  16. The Synergy Between Total Scattering and Advanced Simulation Techniques: Quantifying Geopolymer Gel Evolution

    SciTech Connect

    White, Claire; Bloomer, Breaunnah E.; Provis, John L.; Henson, Neil J.; Page, Katharine L.

    2012-05-16

    With the ever increasing demands for technologically advanced structural materials, together with emerging environmental consciousness due to climate change, geopolymer cement is fast becoming a viable alternative to traditional cements due to proven mechanical engineering characteristics and the reduction in CO2 emitted (approximately 80% less CO2 emitted compared to ordinary Portland cement). Nevertheless, much remains unknown regarding the kinetics of the molecular changes responsible for nanostructural evolution during the geopolymerization process. Here, in-situ total scattering measurements in the form of X-ray pair distribution function (PDF) analysis are used to quantify the extent of reaction of metakaolin/slag alkali-activated geopolymer binders, including the effects of various activators (alkali hydroxide/silicate) on the kinetics of the geopolymerization reaction. Restricting quantification of the kinetics to the initial ten hours of reaction does not enable elucidation of the true extent of the reaction, but using X-ray PDF data obtained after 128 days of reaction enables more accurate determination of the initial extent of reaction. The synergies between the in-situ X-ray PDF data and simulations conducted by multiscale density functional theory-based coarse-grained Monte Carlo analysis are outlined, particularly with regard to the potential for the X-ray data to provide a time scale for kinetic analysis of the extent of reaction obtained from the multiscale simulation methodology.

  17. Synergy in Two-Frequency Fast Wave Cyclotron Harmonic Absorption in DIII-D

    SciTech Connect

    Pinsker, R. I.; Choi, M.; Heidbrink, W. W.; Zhu, Y.; Porkolab, M.; Baity, F. W.; Hosea, J. C.

    2009-11-26

    Fast waves (FWs) at 60 MHz and at 90 MHz are coupled to DIII-D discharges for central heating and current drive at net FW power up to 3.5 MW. The primary absorption mechanism is intended to be direct electron damping in the plasma core. In discharges at B = 2 T with fast deuteron populations from neutral beam injection, 4th and 6th deuterium cyclotron harmonic absorption on the fast ions competes with direct electron damping. Previous experiments have shown that the 6{omega}{sub D} absorption of the 90 MHz FWs is weaker than the 4{omega}{sub D} absorption of 60 MHz FWs, in agreement with a model that includes unspecified edge losses. Recent experiments have shown that if the fast deuterons are accelerated by absorption of 60 MHz (4{omega}{sub D}) FWs, adding 90 MHz power (6{omega}{sub D}) can increase the fusion neutron rate by a larger increment than is obtained with 90 MHz power alone. Details of this synergy between 4{omega}{sub D} and 6{omega}{sub D} absorption are presented.

  18. Cognitive synergy in groups and group-to-individual transfer of decision-making competencies

    PubMed Central

    Curşeu, Petru L.; Meslec, Nicoleta; Pluut, Helen; Lucas, Gerardus J. M.

    2015-01-01

    In a field study (148 participants organized in 38 groups) we tested the effect of group synergy and one's position in relation to the collaborative zone of proximal development (CZPD) on the change of individual decision-making competencies. We used two parallel sets of decision tasks reported in previous research to test rationality and we evaluated individual decision-making competencies in the pre-group and post-group conditions as well as group rationality (as an emergent group level phenomenon). We used multilevel modeling to analyze the data and the results showed that members of synergetic groups had a higher cognitive gain as compared to members of non-synergetic groups, while highly rational members (members above the CZPD) had lower cognitive gains compared to less rational group members (members situated below the CZPD). These insights extend the literature on group-to-individual transfer of learning and have important practical implications as they show that group dynamics influence the development of individual decision-making competencies. PMID:26441750

  19. Educational opportunities based on the university-industry synergies in an open innovation framework

    NASA Astrophysics Data System (ADS)

    Lucia, Óscar; Burdio, José M.; Acero, Jesús; Barragán, Luis A.; Garcia, José R.

    2012-03-01

    Collaboration between Industry and University is becoming more important in order to improve the competitiveness of the research and development activities. Moreover, establishing synergies to bridge the gap between the academic and industrial spheres has demonstrated to be advantageous for both of them. Nowadays, Industry is moving towards an open innovation structure, in which external agents as universities play a key role. Besides, University is also seeking a more active learning methodology to improve the education of students for the real world. Considering this framework, a special effort should be done to take advantage of the collaborative work between Industry and University. The aim of this paper is to present the collaborative framework and the benefits obtained of the educational activities as a consequence of the long-term collaboration established between the University of Zaragoza and the Bosh and Siemens Home Appliances Group. The key stones of the collaboration are presented, and the positive outcomes for the students are highlighted. The strengths, weaknesses, opportunities, and threats of the proposed program are also discussed.

  20. Landfills as critical infrastructures: synergy between non-invasive monitoring technologies

    NASA Astrophysics Data System (ADS)

    Scozzari, Andrea; Raco, Brunella; Battaglini, Raffaele

    2014-05-01

    This work deals with a methodology for estimating the behaviour of a landfill system by means of the integration between two different non-invasive technologies. In fact, there is a widespread agreement on the fact that these infrastructures produce about 23% of the total anthropogenic methane released to the atmosphere. Despite that, there's still no internationally accepted protocol to quantify the leakage of biogas from a landfill with a common standard approach. This work proposes an assessment of the performance of a landfill system in terms of biogas release to the atmosphere. Such evaluation is performed by means of a direct measurement of gas flux with the accumulation chamber method, combined with the detection of thermal anomalies by infrared radiometry. In order to derive flux maps from a set of punctual measurements and calculate an overall quantity of emitted gas, a geostatistical technique is necessarily applied and briefly illustrated. A case study regarding an infrastructure located in Tuscany (Italy) is shown, where a discussion about the evolution of the landfill site through successive campaigns is also suggested. The role played by infrared thermography and its synergy with direct flux measurements is clearly perceivable in this context. The main benefit of the presented approach is a significant increase of the energy recovered from the landfill sites by optimising the collection of biogas, which implies a reduction of the total anthropogenic methane originated from the disposal of wastes released to the atmosphere.

  1. Synergy Between Polyvinylpyrrolidone-Coated Silver Nanoparticles and Azole Antifungal Against Drug-Resistant Candida albicans.

    PubMed

    Sun, Lingmei; Liao, Kai; Li, Yiping; Zhao, Lei; Liang, Sai; Guo, Dan; Hu, Jun; Wang, Dayong

    2016-03-01

    In the clinical practice, resistance of Candida albicans to antifungal agents has frequently emerged. Silver-nanoparticles (Ag-NPs) have been demonstrated to have the antifungal property. We investigated the potential for synergy between polyvinylpyrrolidone (PVP)-coated Ag-NPs and azole antifungal, such as fluconazole or voriconazole, against drug-resistant C. albicans strain CA10. When antifungal agent was examined alone, fluconazole and voriconazole did not kill drug-resistant C. albicans, and PVP-coated Ag-NPs had only the moderate killing ability. In contrast, the combinational treatment of PVP-coated Ag-NPs with fluconazole or voriconazole was effective in being against the drug-resistant C. albicans. After the combinational treatment, we detected the disruption of cell membrane integrity, the tendency of PVP-coated Ag-NPs to adhere to cell membrane, and the inhibition of budding process. Moreover, after the combinational treatment, the defects in ergosterol signaling and efflux pump functions were detected. Our results suggest that the combinational use of engineered nanomaterials (ENMs), such as PVP-coated Ag-NPs, with the conventional antifungal may be a viable strategy to combat drug-resistant fungal infection. PMID:27455637

  2. Tradeoffs and synergies between biofuel production and large-scale solar infrastructure in deserts

    NASA Astrophysics Data System (ADS)

    Ravi, S.; Lobell, D. B.; Field, C. B.

    2012-12-01

    Solar energy installations in deserts are on the rise, fueled by technological advances and policy changes. Deserts, with a combination of high solar radiation and availability of large areas unusable for crop production are ideal locations for large scale solar installations. For efficient power generation, solar infrastructures require large amounts of water for operation (mostly for cleaning panels and dust suppression), leading to significant moisture additions to desert soil. A pertinent question is how to use the moisture inputs for sustainable agriculture/biofuel production. We investigated the water requirements for large solar infrastructures in North American deserts and explored the possibilities for integrating biofuel production with solar infrastructure. In co-located systems the possible decline in yields due to shading by solar panels may be offsetted by the benefits of periodic water addition to biofuel crops, simpler dust management and more efficient power generation in solar installations, and decreased impacts on natural habitats and scarce resources in deserts. In particular, we evaluated the potential to integrate solar infrastructure with biomass feedstocks that grow in arid and semi-arid lands (Agave Spp), which are found to produce high yields with minimal water inputs. To this end, we conducted detailed life cycle analysis for these coupled agave biofuel - solar energy systems to explore the tradeoffs and synergies, in the context of energy input-output, water use and carbon emissions.

  3. Revolutions in Galaxy Cluster Science: Astro-H/eROSITA Synergy and Athena Outlook

    NASA Astrophysics Data System (ADS)

    Reiprich, Thomas

    eROSITA will perform the first X-ray imaging all-sky survey up to 10 keV and is expected to detect about 100,000 galaxy clusters. It is planned to be launched as the primary instrument of the Spectrum-Roentgen-Gamma mission, around the same time as Astro-H. To reach its major scientific goal -- unprecedented constraints on dark energy -- the cluster masses need to be known accurately. Astro-H will allow us for the first time to tightly constrain sources of non-thermal pressure support in galaxy clusters through its revolutionary micro-calorimeter array, and thereby to quantify one of the primary systematic uncertainties in X-ray mass measurements. The excellent synergy between eROSITA and Astro-H for clusters and cosmology will be illustrated. Moreover, at the end of the next decade, Athena is expected to be launched. Examples will be shown how Athena's combination of high throughput and excellent spectral resolution will enable breakthroughs in our understanding of cluster evolution.

  4. A synergy of values. Catholic healthcare leaders must implement their organization's mission and model its values.

    PubMed

    Clifton, R M; McEnroe, J J

    1994-06-01

    Catholic organizations need to select, develop, and retain healthcare leaders who dedicate themselves to carrying on the Church's healing ministry and the work begun by those who have preceded them. Persons entrusted to carry on Jesus' healing mission perform their duties out of a sense of commitment to the ministry and a love for the persons with whom they work and whom they serve. They recognize a synergy between their own values and the values of the healthcare organizations they lead. Dedication to leadership in Catholic healthcare can be viewed from three perspectives: the Bible and selected documents of the Catholic Church; the transfer of responsibility for Catholic healthcare from religious congregations to evolving forms of sponsorship; and the implications for the selection, development, and retention of healthcare leaders, both lay and religious. Servant-leadership is an integral part of the religious tradition that underlies Catholic healthcare. As cooperation increases between healthcare providers, third-party payers, employers, and other healthcare agents. Catholic healthcare organizations are challenged to reassert a mission and values that will enable healthcare in the United States to be delivered both compassionately and competently. PMID:10134188

  5. Pore Structure and Synergy in Antimicrobial Peptides of the Magainin Family

    PubMed Central

    Pino-Angeles, Almudena; Leveritt, John M.; Lazaridis, Themis

    2016-01-01

    Magainin 2 and PGLa are among the best-studied cationic antimicrobial peptides. They bind preferentially to negatively charged membranes and apparently cause their disruption by the formation of transmembrane pores, whose detailed structure is still unclear. Here we report the results of 5–9 μs all-atom molecular dynamics simulations starting from tetrameric transmembrane helical bundles of these two peptides, as well as their stoichiometric mixture, and the analog MG-H2 in DMPC or 3:1 DMPC/DMPG membranes. The simulations produce pore structures that appear converged, although some effect of the starting peptide arrangement (parallel vs. antiparallel) is still observed on this timescale. The peptides remain mostly helical and adopt tilted orientations. The calculated tilt angles for PGLa are in excellent agreement with recent solid state NMR experiments. The antiparallel dimer structure in the magainin 2 simulations resembles previously determined NMR and crystal structures. More transmembrane orientations and a larger and more ordered pore are seen in the 1:1 heterotetramer with an antiparallel helix arrangement. Insights into the mechanism of synergy between these two peptides are obtained via implicit solvent modeling of homo- and heterodimers and analysis of interactions in the atomistic simulations. This analysis suggests stronger pairwise interactions in the heterodimer than in the two homodimers. PMID:26727376

  6. Effects of Design Variants in Lower-Limb Prostheses on Gait Synergy

    PubMed Central

    Pitkin, Mark R.

    2016-01-01

    A lower-limb prosthesis is the mechanical device with which an amputee’s residual limb interacts with the walking surface. The pressure and shear forces that affect the residuum due to prosthesis use are the sources of pain, residual-limb skin problems and gait deviations. Direct approaches to reducing these problems include improving fit, alignment technique and socket design as well as increasing cushioning with socket liners. A summary of typical malalignments and their consequences is presented. The malalignments are considered sources of excessive moments applied to the residuum, which simplifies the analysis of a patient’s gait. A better design of prosthetic joints could improve prosthetic gait. This article addresses the key mechanical parameter of prosthetic joints, namely the dependence “moment of resistance/angle of deflection.” A mathematical model has been developed that links stresses on the residuum in transtibial amputees with the moment of resistance in the prosthetic ankle at the critical gait phases. Analysis of the model yields a substantial decrease in stresses on the residuum during the most demanding, load-bearing phase of stance if the moment of resistance in the ankle is similar to that seen in the biological ankle joint. Gait study shows use of the experimental rolling-joint prosthetic foot more closely simulates normal gait synergy than the SACH foot. PMID:27087763

  7. Synergy and Mode of Action of Ceftazidime plus Quercetin or Luteolin on Streptococcus pyogenes

    PubMed Central

    Siriwong, Supatcharee; Thumanu, Kanjana; Hengpratom, Tanaporn; Eumkeb, Griangsak

    2015-01-01

    Streptococcus pyogenes causes streptococcal toxic shock syndrome. The recommended therapy has been often failure through the interfering of beta-lactamase-producing bacteria (BLPB). The present study was to investigate antibacterial activity, synergy, and modes of action of luteolin and quercetin using alone and plus ceftazidime against S. pyogenes. The MICs of ceftazidime, luteolin, and quercetin against all S. pyogenes were 0.50, 128, and 128 µg mL−1, respectively. A synergistic effect was exhibited on luteolin and quercetin plus ceftazidime against these strains at fractional inhibitory concentration indices 0.37 and 0.27, respectively, and was confirmed by the viable count. These combinations increased cytoplasmic membrane (CM) permeability, caused irregular cell shape, peptidoglycan, and CM damage, and decreased nucleic acid but increased proteins in bacterial cells. Enzyme assay demonstrated that these flavonoids had an inhibitory activity against β-lactamase. In summary, this study provides evidence that the inhibitory mode of action of luteolin and quercetin may be mediated via three mechanisms: (1) inhibiting of peptidoglycan synthesis, (2) increasing CM permeability, and (3) decreasing nucleic acid but increasing the protein contents of bacterial cells. So, luteolin and quercetin propose the high potential to develop adjunct to ceftazidime for the treatment of coexistence of the BLPB and S. pyogenes infections. PMID:26576195

  8. Composition- and Structure-Tunable Gold-Cobalt Nanoparticles and Electrocatalytic Synergy for Oxygen Evolution Reaction.

    PubMed

    Lu, Aolin; Peng, Dong-Liang; Chang, Fangfang; Skeete, Zakiya; Shan, Shiyao; Sharma, Anju; Luo, Jin; Zhong, Chuan-Jian

    2016-08-10

    The increasing energy crisis constitutes an inspiring drive seeking alternative energies such as hydrogen from water splitting which is clean and abundant, but a key challenge for water splitting is the need of highly efficient catalysts for oxygen evolution reaction (OER). This report describes findings of an investigation of the synthesis of gold-cobalt (AuCo) nanoparticles by a facile one-pot and injection method and their use as highly efficient catalysts for OER. While particle size depends on the synthesis method, the composition of the nanoparticles is controlled by feeding ratio of Au and Co precursors in the synthesis. Depending on Co content, the nanoparticles exhibit largely phase-segregated domains with a core (Au)-shell (Co) type of structure at a high level of Co. Upon the thermochemical treatment of carbon-supported AuCo nanoparticles, the redox activity of Co species in the nanoparticles with cycle number is shown to decrease which changes the surface oxidation state of Co species without changing the composition significantly. The electrocatalytic activity for OER in alkaline electrolytes is shown to depend on the bimetallic composition, displaying a maximum activity for an Au:Co ratio of ∼2:3. This dependence is also shown to correlate with the surface oxidation state and redox activities, providing an insight into the electrocatalytic activity. Mechanistic aspects of the electrocataltytic properties are discussed in terms of the bifunctional synergy of Co and Au in the nanoparticle catalysts. PMID:27479685

  9. Occurrence of Lipophilic Marine Toxins in Shellfish from Galicia (NW of Spain) and Synergies among Them

    PubMed Central

    Rodríguez, Laura P.; González, Virginia; Martínez, Aníbal; Paz, Beatriz; Lago, Jorge; Cordeiro, Victoria; Blanco, Lucía; Vieites, Juan Manuel; Cabado, Ana G.

    2015-01-01

    Lipophilic marine toxins pose a serious threat for consumers and an enormous economic problem for shellfish producers. Synergistic interaction among toxins may play an important role in the toxicity of shellfish and consequently in human intoxications. In order to study the toxic profile of molluscs, sampled during toxic episodes occurring in different locations in Galicia in 2014, shellfish were analyzed by liquid chromatography tandem mass spectrometry (LC–MS/MS), the official method for the detection of lipophilic toxins. The performance of this procedure was demonstrated to be fit for purpose and was validated in house following European guidelines. The vast majority of toxins present in shellfish belonged to the okadaic acid (OA) group and some samples from a particular area contained yessotoxin (YTX). Since these toxins occur very often with other lipophilic toxins, we evaluated the potential interactions among them. A human neuroblastoma cell line was used to study the possible synergies of OA with other lipophilic toxins. Results show that combination of OA with dinophysistoxin 2 (DTX2) or YTX enhances the toxicity triggered by OA, decreasing cell viability and cell proliferation, depending on the toxin concentration and incubation time. The effects of other lipophilic toxins as 13-desmethyl Spirolide C were also evaluated in vitro. PMID:25815891

  10. A Synergy-Based Optimally Designed Sensing Glove for Functional Grasp Recognition.

    PubMed

    Ciotti, Simone; Battaglia, Edoardo; Carbonaro, Nicola; Bicchi, Antonio; Tognetti, Alessandro; Bianchi, Matteo

    2016-01-01

    Achieving accurate and reliable kinematic hand pose reconstructions represents a challenging task. The main reason for this is the complexity of hand biomechanics, where several degrees of freedom are distributed along a continuous deformable structure. Wearable sensing can represent a viable solution to tackle this issue, since it enables a more natural kinematic monitoring. However, the intrinsic accuracy (as well as the number of sensing elements) of wearable hand pose reconstruction (HPR) systems can be severely limited by ergonomics and cost considerations. In this paper, we combined the theoretical foundations of the optimal design of HPR devices based on hand synergy information, i.e., the inter-joint covariation patterns, with textile goniometers based on knitted piezoresistive fabrics (KPF) technology, to develop, for the first time, an optimally-designed under-sensed glove for measuring hand kinematics. We used only five sensors optimally placed on the hand and completed hand pose reconstruction (described according to a kinematic model with 19 degrees of freedom) leveraging upon synergistic information. The reconstructions we obtained from five different subjects were used to implement an unsupervised method for the recognition of eight functional grasps, showing a high degree of accuracy and robustness. PMID:27271621

  11. Synergy and destructive interferences between local magnetic anisotropies in binuclear complexes

    SciTech Connect

    Guihéry, Nathalie; Ruamps, Renaud; Maurice, Rémi

    2015-12-31

    Magnetic anisotropy is responsible for the single molecule magnet behavior of transition metal complexes. This behavior is characterized by a slow relaxation of the magnetization for low enough temperatures, and thus for a possible blocking of the magnetization. This bistable behavior can lead to possible technological applications in the domain of data storage or quantum computing. Therefore, the understanding of the microscopic origin of magnetic anisotropy has received a considerable interest during the last two decades. The presentation focuses on the determination of the anisotropy parameters of both mono-nuclear and bi-nuclear types of complexes and on the control and optimization of the anisotropic properties. The validity of the model Hamiltonians commonly used to characterize such complexes has been questioned and it is shown that neither the standard multispin Hamiltonian nor the giant spin Hamiltonian are appropriate for weakly coupled ions. Alternative models have been proposed and used to properly extract the relevant parameters. Rationalizations of the magnitude and nature of both local anisotropies of single ions and the molecular anisotropy of polynuclear complexes are provided. The synergy and interference effects between local magnetic anisotropies are studied in a series of binuclear complexes.

  12. A Synergy-Based Optimally Designed Sensing Glove for Functional Grasp Recognition

    PubMed Central

    Ciotti, Simone; Battaglia, Edoardo; Carbonaro, Nicola; Bicchi, Antonio; Tognetti, Alessandro; Bianchi, Matteo

    2016-01-01

    Achieving accurate and reliable kinematic hand pose reconstructions represents a challenging task. The main reason for this is the complexity of hand biomechanics, where several degrees of freedom are distributed along a continuous deformable structure. Wearable sensing can represent a viable solution to tackle this issue, since it enables a more natural kinematic monitoring. However, the intrinsic accuracy (as well as the number of sensing elements) of wearable hand pose reconstruction (HPR) systems can be severely limited by ergonomics and cost considerations. In this paper, we combined the theoretical foundations of the optimal design of HPR devices based on hand synergy information, i.e., the inter-joint covariation patterns, with textile goniometers based on knitted piezoresistive fabrics (KPF) technology, to develop, for the first time, an optimally-designed under-sensed glove for measuring hand kinematics. We used only five sensors optimally placed on the hand and completed hand pose reconstruction (described according to a kinematic model with 19 degrees of freedom) leveraging upon synergistic information. The reconstructions we obtained from five different subjects were used to implement an unsupervised method for the recognition of eight functional grasps, showing a high degree of accuracy and robustness. PMID:27271621

  13. Nanoparticle synergies in modifying thermal conductivity for heat exchanger in condensing boilers

    NASA Astrophysics Data System (ADS)

    Yang, Kai; He, Shan; Butcher, Thomas; Trojanowski, Rebecca; Sun, Ning; Gersappe, Dilip; Rafailovich, Miriam

    2013-03-01

    The heat exchanger we are using for condensing boilers is mainly made from aluminum alloys and stainless steel. However, the metal is relatively expensive and corrosion together with maintenance is also a big problem. Therefore, we have developed a new design and material which contain carbon black, carbon nanotube, aluminum oxide and graphene as additives in polypropylene. When multiple types of particles can be melt blended simultaneously and synergies can be achieved, imparting particles to the nanocomposite, achieved much higher thermal conductivity rather than single additive. Here we show the flame retardant nanocomposite which can pass the UL-94-V0 vertical burning test, perform nice in Cone Calorimetry Test and has relatively good mechanical properties. SEM images of the blend show that the Carbon nanobute and other additives well dispersed within the polymer matrix which match our computational calculation for getting the percolation to achieve thermal conductivity around 1.5W/m .K rather than 0.23W/m .K as pure polypropylene. Haydale/Cheap Tubes

  14. The role of nanoparticle synergies in modifying the thermal properties of biodegradable polymer blends

    NASA Astrophysics Data System (ADS)

    Yang, Kai; He, Shan; Davis, Rachel; Rafailovich, Miriam; Kashiwagi, Takashi

    2012-02-01

    Most of thermoplastic polymers are brittle, when sufficient amounts are added to get flame retardant properties.Furthermore, melt-blending starch with other biodegradable polymers is difficult since very few polymers are compatible with starches.We have developed a new nanoparticles where resorcinol diphenyl phosphates (RDP) is used to modify the surface energy, allowing the particles to be dispersed within polymer.When multiple types of particles share the same coating,they can be melt blended simultaneously and synergies can be achieved, imparting properties to the nanocomposite, which cannot be achieved by any single additive. Here we show that RDP modified starch, can be extruded together with the biodegradable polymers,Ecoflex and polylactic acid,to produce flame retardant nanocomposites which can pass the UL-94-V0 test.TEM images of the blend show that the RDP-coated starch particles were well dispersed within the polymer matrix providing the flame retardant properties,while the RDP clays are reducing the interfacial tension and contributing to compatibilization. Nanomechanical measurements of the chars remaining after cone calorimetric measurements indicate that maintaining flexibility of the chars may be an additional factor in achieving good flame retardant properties.

  15. Response of Aphidius colemani to aphid sex pheromone varies depending on plant synergy and prior experience.

    PubMed

    Fernández-Grandon, G M; Poppy, G M

    2015-08-01

    A critical stage in the success of a parasitoid is the ability to locate a host within its habitat. It is hypothesized that a series of olfactory cues may be involved in altering the parasitoid's movement patterns at this stage of foraging. This paper focuses specifically on host habitat location and host location and the olfactory stimuli necessary to mediate the transition between these stages. Firstly, we confirm the ability of the parasitoid Aphidius colemani to detect the aphid sex pheromone at an electrophysiological level. Following this we investigate the effect of the sex pheromone component (4aS,7S,7aR)-nepetalactone on the movement patterns of A. colemani and its retention within an area. The key findings of this work are that A. colemani is able to detect the sex pheromone components, that parasitoid retention is increased by a synergy of nepetalactone and other host-associated cues and that foraging patterns are augmented by the presence of nepetalactone or experience associated with nepetalactone. PMID:25991073

  16. Functional synergy between the Munc13 C-terminal C1 and C2 domains

    PubMed Central

    Liu, Xiaoxia; Seven, Alpay Burak; Camacho, Marcial; Esser, Victoria; Xu, Junjie; Trimbuch, Thorsten; Quade, Bradley; Su, Lijing; Ma, Cong; Rosenmund, Christian; Rizo, Josep

    2016-01-01

    Neurotransmitter release requires SNARE complexes to bring membranes together, NSF-SNAPs to recycle the SNAREs, Munc18-1 and Munc13s to orchestrate SNARE complex assembly, and Synaptotagmin-1 to trigger fast Ca2+-dependent membrane fusion. However, it is unclear whether Munc13s function upstream and/or downstream of SNARE complex assembly, and how the actions of their multiple domains are integrated. Reconstitution, liposome-clustering and electrophysiological experiments now reveal a functional synergy between the C1, C2B and C2C domains of Munc13-1, indicating that these domains help bridging the vesicle and plasma membranes to facilitate stimulation of SNARE complex assembly by the Munc13-1 MUN domain. Our reconstitution data also suggest that Munc18-1, Munc13-1, NSF, αSNAP and the SNAREs are critical to form a ‘primed’ state that does not fuse but is ready for fast fusion upon Ca2+ influx. Overall, our results support a model whereby the multiple domains of Munc13s cooperate to coordinate synaptic vesicle docking, priming and fusion. DOI: http://dx.doi.org/10.7554/eLife.13696.001 PMID:27213521

  17. Bioeconomic synergy between tactics for insect eradication in the presence of Allee effects.

    PubMed

    Blackwood, Julie C; Berec, Ludek; Yamanaka, Takehiko; Epanchin-Niell, Rebecca S; Hastings, Alan; Liebhold, Andrew M

    2012-07-22

    Preventing the establishment of invading pest species can be beneficial with respect to averting future environmental and economic impacts and also in preventing the accumulation of control costs. Allee effects play an important role in the dynamics of newly established, low-density populations by driving small populations into self-extinction, making Allee effects critical in influencing outcomes of eradication efforts. We consider interactions between management tactics in the presence of Allee effects to determine cost-effective and time-efficient combinations to achieve eradication by developing a model that considers pesticide application, predator augmentation and mating disruption as control tactics, using the gypsy moth as a case study. Our findings indicate that given a range of constant expenditure levels, applying moderate levels of pesticides in conjunction with mating disruption increases the Allee threshold which simultaneously substantially decreases the time to eradication relative to either tactic alone. In contrast, increasing predation in conjunction with other tactics requires larger economic expenditures to achieve similar outcomes for the use of pesticide application or mating disruption alone. These results demonstrate the beneficial synergy that may arise from nonlinearities associated with the simultaneous application of multiple eradication tactics and offer new prospects for preventing the establishment of damaging non-native species. PMID:22438497

  18. Functional synergy between the Munc13 C-terminal C1 and C2 domains.

    PubMed

    Liu, Xiaoxia; Seven, Alpay Burak; Camacho, Marcial; Esser, Victoria; Xu, Junjie; Trimbuch, Thorsten; Quade, Bradley; Su, Lijing; Ma, Cong; Rosenmund, Christian; Rizo, Josep

    2016-01-01

    Neurotransmitter release requires SNARE complexes to bring membranes together, NSF-SNAPs to recycle the SNAREs, Munc18-1 and Munc13s to orchestrate SNARE complex assembly, and Synaptotagmin-1 to trigger fast Ca(2+)-dependent membrane fusion. However, it is unclear whether Munc13s function upstream and/or downstream of SNARE complex assembly, and how the actions of their multiple domains are integrated. Reconstitution, liposome-clustering and electrophysiological experiments now reveal a functional synergy between the C1, C2B and C2C domains of Munc13-1, indicating that these domains help bridging the vesicle and plasma membranes to facilitate stimulation of SNARE complex assembly by the Munc13-1 MUN domain. Our reconstitution data also suggest that Munc18-1, Munc13-1, NSF, αSNAP and the SNAREs are critical to form a 'primed' state that does not fuse but is ready for fast fusion upon Ca(2+) influx. Overall, our results support a model whereby the multiple domains of Munc13s cooperate to coordinate synaptic vesicle docking, priming and fusion. PMID:27213521

  19. A Riemannian geometry theory of human movement: The geodesic synergy hypothesis.

    PubMed

    Neilson, Peter D; Neilson, Megan D; Bye, Robin T

    2015-12-01

    Mass-inertia loads on muscles change with posture and with changing mechanical interactions between the body and the environment. The nervous system must anticipate changing mass-inertia loads, especially during fast multi-joint coordinated movements. Riemannian geometry provides a mathematical framework for movement planning that takes these inertial interactions into account. To demonstrate this we introduce the controlled (vs. biomechanical) degrees of freedom of the body as the coordinate system for a configuration space with movements represented as trajectories. This space is not Euclidean. It is endowed at each point with a metric equal to the mass-inertia matrix of the body in that configuration. This warps the space to become Riemannian with curvature at each point determined by the differentials of the mass-inertia at that point. This curvature takes nonlinear mass-inertia interactions into account with lengths, velocities, accelerations and directions of movement trajectories all differing from those in Euclidean space. For newcomers to Riemannian geometry we develop the intuitive groundwork for a Riemannian field theory of human movement encompassing the entire body moving in gravity and in mechanical interaction with the environment. In particular we present a geodesic synergy hypothesis concerning planning of multi-joint coordinated movements to achieve goals with minimal muscular effort. PMID:26302481

  20. The Synergies research-practice partnership project: a 2020 Vision case study

    NASA Astrophysics Data System (ADS)

    Falk, John H.; Dierking, Lynn D.; Staus, Nancy L.; Wyld, Jennifer N.; Bailey, Deborah L.; Penuel, William R.

    2016-03-01

    This paper, describes Synergies, an on-going longitudinal study and design effort, being conducted in a diverse, under-resourced community in Portland, Oregon, with the goal of measurably improving STEM learning, interest and participation by early adolescents, both in school and out of school. Authors examine how the work of this particular research-practice partnership is attempting to accommodate the six principles outlined in this issue: (1) to more accurately reflect learning as a lifelong process occurring across settings, situations and time frames; (2) to consider what STEM content is worth learning; (3) to examine learning as a cultural process, involving varied repertoires of practice across learners' everyday lives; (4) to directly involve practitioners (and learners) in the research process; (5) to document how existing and emerging technologies and new media are, and will continue, to shape and redefine the content and practice of STEM learning research; and, (6) to take into account the broader socio-cultural-political contexts of the needs and concerns of the larger global society.

  1. Synergy and destructive interferences between local magnetic anisotropies in binuclear complexes

    NASA Astrophysics Data System (ADS)

    Guihéry, Nathalie; Ruamps, Renaud; Maurice, Rémi; de Graaf, Coen

    2015-12-01

    Magnetic anisotropy is responsible for the single molecule magnet behavior of transition metal complexes. This behavior is characterized by a slow relaxation of the magnetization for low enough temperatures, and thus for a possible blocking of the magnetization. This bistable behavior can lead to possible technological applications in the domain of data storage or quantum computing. Therefore, the understanding of the microscopic origin of magnetic anisotropy has received a considerable interest during the last two decades. The presentation focuses on the determination of the anisotropy parameters of both mono-nuclear and bi-nuclear types of complexes and on the control and optimization of the anisotropic properties. The validity of the model Hamiltonians commonly used to characterize such complexes has been questioned and it is shown that neither the standard multispin Hamiltonian nor the giant spin Hamiltonian are appropriate for weakly coupled ions. Alternative models have been proposed and used to properly extract the relevant parameters. Rationalizations of the magnitude and nature of both local anisotropies of single ions and the molecular anisotropy of polynuclear complexes are provided. The synergy and interference effects between local magnetic anisotropies are studied in a series of binuclear complexes.

  2. Hybrid Rocket Motor Test

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Stennis Space Center conducts a test on a hybrid rocket motor fed by a liquid oxygen turbopump. The test occurred at the E-1 test facility. The test was believed to be the first of its kind in the world.

  3. Hybrid rocket combustion study

    NASA Astrophysics Data System (ADS)

    Strand, L. D.; Ray, R. L.; Cohen, N. S.

    1993-06-01

    The objectives of this study of 'pure' or 'classic' hybrids are to (1) extend our understanding of the boundary layer combustion process and the critical engineering parameters that define this process, (2) develop an up-to-date hybrid fuel combustion model, and (3) apply the model to correlate the regression rate and scaling properties of potential fuel candidates. Tests were carried out with a hybrid slab window motor, using several diagnostic techniques, over a range of motor pressure and oxidizer mass flux conditions. The results basically confirmed turbulent boundary layer heat and mass transfer as the rate limiting process for hybrid fuel decomposition and combustion. The measured fuel regression rates showed good agreement with the analytical model predictions. The results of model scaling calculations to Shuttle SRM size conditions are presented.

  4. Hybrid adsorptive membrane reactor

    DOEpatents

    Tsotsis, Theodore T.; Sahimi, Muhammad; Fayyaz-Najafi, Babak; Harale, Aadesh; Park, Byoung-Gi; Liu, Paul K. T.

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  5. Hybrid rocket combustion study

    NASA Technical Reports Server (NTRS)

    Strand, L. D.; Ray, R. L.; Cohen, N. S.

    1993-01-01

    The objectives of this study of 'pure' or 'classic' hybrids are to (1) extend our understanding of the boundary layer combustion process and the critical engineering parameters that define this process, (2) develop an up-to-date hybrid fuel combustion model, and (3) apply the model to correlate the regression rate and scaling properties of potential fuel candidates. Tests were carried out with a hybrid slab window motor, using several diagnostic techniques, over a range of motor pressure and oxidizer mass flux conditions. The results basically confirmed turbulent boundary layer heat and mass transfer as the rate limiting process for hybrid fuel decomposition and combustion. The measured fuel regression rates showed good agreement with the analytical model predictions. The results of model scaling calculations to Shuttle SRM size conditions are presented.

  6. Hybrid adsorptive membrane reactor

    NASA Technical Reports Server (NTRS)

    Tsotsis, Theodore T. (Inventor); Sahimi, Muhammad (Inventor); Fayyaz-Najafi, Babak (Inventor); Harale, Aadesh (Inventor); Park, Byoung-Gi (Inventor); Liu, Paul K. T. (Inventor)

    2011-01-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  7. Plum and plum hybrids.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirty-six plum and plum hybrid cultivars are briefly described for the Fruit and Nut Register 45. This register is made to keep the plum industry and researchers up to date on the latest cultivars released....

  8. Hybrid plasmachemical reactor

    SciTech Connect

    Lelevkin, V. M. Smirnova, Yu. G.; Tokarev, A. V.

    2015-04-15

    A hybrid plasmachemical reactor on the basis of a dielectric barrier discharge in a transformer is developed. The characteristics of the reactor as functions of the dielectric barrier discharge parameters are determined.

  9. Hybrid image processing

    NASA Technical Reports Server (NTRS)

    Juday, Richard D.

    1990-01-01

    Partly-digital, partly-optical 'hybrid' image processing attempts to use the properties of each domain to synergistic advantage: while Fourier optics furnishes speed, digital processing allows the use of much greater algorithmic complexity. The video-rate image-coordinate transformation used is a critical technology for real-time hybrid image-pattern recognition. Attention is given to the separation of pose variables, image registration, and both single- and multiple-frame registration.

  10. Intra-Auditory Integration Improves Motor Performance and Synergy in an Accurate Multi-Finger Pressing Task

    PubMed Central

    Koh, Kyung; Kwon, Hyun Joon; Park, Yang Sun; Kiemel, Tim; Miller, Ross H.; Kim, Yoon Hyuk; Shin, Joon-Ho; Shim, Jae Kun

    2016-01-01

    Humans detect changes in the air pressure and understand the surroundings through the auditory system. The sound humans perceive is composed of two distinct physical properties, frequency and intensity. However, our knowledge is limited how the brain perceives and combines these two properties simultaneously (i.e., intra-auditory integration), especially in relation to motor behaviors. Here, we investigated the effect of intra-auditory integration between the frequency and intensity components of auditory feedback on motor outputs in a constant finger-force production task. The hierarchical variability decomposition model previously developed was used to decompose motor performance into mathematically independent components each of which quantifies a distinct motor behavior such as consistency, repeatability, systematic error, within-trial synergy, or between-trial synergy. We hypothesized that feedback on two components of sound as a function of motor performance (frequency and intensity) would improve motor performance and multi-finger synergy compared to feedback on just one component (frequency or intensity). Subjects were instructed to match the reference force of 18 N with the sum of all finger forces (virtual finger or VF force) while listening to auditory feedback of their accuracy. Three experimental conditions were used: (i) condition F, where frequency changed; (ii) condition I, where intensity changed; (iii) condition FI, where both frequency and intensity changed. Motor performance was enhanced for the FI conditions as compared to either the F or I condition alone. The enhancement of motor performance was achieved mainly by the improved consistency and repeatability. However, the systematic error remained unchanged across conditions. Within- and between-trial synergies were also improved for the FI condition as compared to either the F or I condition alone. However, variability of individual finger forces for the FI condition was not significantly

  11. Intra-Auditory Integration Improves Motor Performance and Synergy in an Accurate Multi-Finger Pressing Task.

    PubMed

    Koh, Kyung; Kwon, Hyun Joon; Park, Yang Sun; Kiemel, Tim; Miller, Ross H; Kim, Yoon Hyuk; Shin, Joon-Ho; Shim, Jae Kun

    2016-01-01

    Humans detect changes in the air pressure and understand the surroundings through the auditory system. The sound humans perceive is composed of two distinct physical properties, frequency and intensity. However, our knowledge is limited how the brain perceives and combines these two properties simultaneously (i.e., intra-auditory integration), especially in relation to motor behaviors. Here, we investigated the effect of intra-auditory integration between the frequency and intensity components of auditory feedback on motor outputs in a constant finger-force production task. The hierarchical variability decomposition model previously developed was used to decompose motor performance into mathematically independent components each of which quantifies a distinct motor behavior such as consistency, repeatability, systematic error, within-trial synergy, or between-trial synergy. We hypothesized that feedback on two components of sound as a function of motor performance (frequency and intensity) would improve motor performance and multi-finger synergy compared to feedback on just one component (frequency or intensity). Subjects were instructed to match the reference force of 18 N with the sum of all finger forces (virtual finger or VF force) while listening to auditory feedback of their accuracy. Three experimental conditions were used: (i) condition F, where frequency changed; (ii) condition I, where intensity changed; (iii) condition FI, where both frequency and intensity changed. Motor performance was enhanced for the FI conditions as compared to either the F or I condition alone. The enhancement of motor performance was achieved mainly by the improved consistency and repeatability. However, the systematic error remained unchanged across conditions. Within- and between-trial synergies were also improved for the FI condition as compared to either the F or I condition alone. However, variability of individual finger forces for the FI condition was not significantly

  12. Systems for hybrid cars

    NASA Astrophysics Data System (ADS)

    Bitsche, Otmar; Gutmann, Guenter

    Not only sharp competition but also legislation are pushing development of hybrid drive trains. Based on conventional internal combustion engine (ICE) vehicles, these drive trains offer a wide range of benefits from reduced fuel consumption and emission to multifaceted performance improvements. Hybrid electric drive trains may also facilitate the introduction of fuel cells (FC). The battery is the key component for all hybrid drive trains, as it dominates cost and performance issues. The selection of the right battery technology for the specific automotive application is an important task with an impact on costs of development and use. Safety, power, and high cycle life are a must for all hybrid applications. The greatest pressure to reduce cost is in soft hybrids, where lead-acid embedded in a considerate management presents the cheapest solution, with a considerable improvement in performance needed. From mild to full hybridization, an improvement in specific power makes higher costs more acceptable, provided that the battery's service life is equivalent to the vehicle's lifetime. Today, this is proven for the nickel-metal hydride system. Lithium ion batteries, which make use of a multiple safety concept, and with some development anticipated, provide even better prospects in terms of performance and costs. Also, their scalability permits their application in battery electric vehicles—the basis for better performance and enhanced user acceptance. Development targets for the batteries are discussed with a focus on system aspects such as electrical and thermal management and safety.

  13. Mind the gap in SEA: An institutional perspective on why assessment of synergies amongst climate change mitigation, adaptation and other policy areas are missing

    SciTech Connect

    Vammen Larsen, Sanne; Kornov, Lone; Wejs, Anja

    2012-02-15

    This article takes its point of departure in two approaches to integrating climate change into Strategic Environmental Assessment (SEA): Mitigation and adaptation, and in the fact that these, as well as the synergies between them and other policy areas, are needed as part of an integrated assessment and policy response. First, the article makes a review of how positive and negative synergies between a) climate change mitigation and adaptation and b) climate change and other environmental concerns are integrated into Danish SEA practice. Then, the article discusses the implications of not addressing synergies. Finally, the article explores institutional explanations as to why synergies are not addressed in SEA practice. A document analysis of 149 Danish SEA reports shows that only one report comprises the assessment of synergies between mitigation and adaptation, whilst 9,4% of the reports assess the synergies between climate change and other environmental concerns. The consequences of separation are both the risk of trade-offs and missed opportunities for enhancing positive synergies. In order to propose explanations for the lacking integration, the institutional background is analysed and discussed, mainly based on Scott's theory of institutions. The institutional analysis highlights a regulatory element, since the assessment of climate change synergies is underpinned by legislation, but not by guidance. This means that great focus is on normative elements such as the local interpretation of legislation and of climate change mitigation and adaptation. The analysis also focuses on how the fragmentation of the organisation in which climate change and SEA are embedded has bearings on both normative and cultural-cognitive elements. This makes the assessment of synergies challenging. The evidence gathered and presented in the article points to a need for developing the SEA process and methodology in Denmark with the aim to include climate change in the assessments in a

  14. Strategic Co-Location in a Hybrid Process Involving Desalination and Pressure Retarded Osmosis (PRO).

    PubMed

    Sim, Victor S T; She, Qianhong; Chong, Tzyy Haur; Tang, Chuyang Y; Fane, Anthony G; Krantz, William B

    2013-01-01

    This paper focuses on a Hybrid Process that uses feed salinity dilution and osmotic power recovery from Pressure Retarded Osmosis (PRO) to achieve higher overall water recovery. This reduces the energy consumption and capital costs of conventional seawater desalination and water reuse processes. The Hybrid Process increases the amount of water recovered from the current 66.7% for conventional seawater desalination and water reuse processes to a potential 80% through the use of reclaimed water brine as an impaired water source. A reduction of up to 23% in energy consumption is projected via the Hybrid Process. The attractiveness is amplified by potential capital cost savings ranging from 8.7%-20% compared to conventional designs of seawater desalination plants. A decision matrix in the form of a customizable scorecard is introduced for evaluating a Hybrid Process based on the importance of land space, capital costs, energy consumption and membrane fouling. This study provides a new perspective, looking at processes not as individual systems but as a whole utilizing strategic co-location to unlock the synergies available in the water-energy nexus for more sustainable desalination. PMID:24956940

  15. Strategic Co-Location in a Hybrid Process Involving Desalination and Pressure Retarded Osmosis (PRO)

    PubMed Central

    Sim, Victor S.T.; She, Qianhong; Chong, Tzyy Haur; Tang, Chuyang Y.; Fane, Anthony G.; Krantz, William B.

    2013-01-01

    This paper focuses on a Hybrid Process that uses feed salinity dilution and osmotic power recovery from Pressure Retarded Osmosis (PRO) to achieve higher overall water recovery. This reduces the energy consumption and capital costs of conventional seawater desalination and water reuse processes. The Hybrid Process increases the amount of water recovered from the current 66.7% for conventional seawater desalination and water reuse processes to a potential 80% through the use of reclaimed water brine as an impaired water source. A reduction of up to 23% in energy consumption is projected via the Hybrid Process. The attractiveness is amplified by potential capital cost savings ranging from 8.7%–20% compared to conventional designs of seawater desalination plants. A decision matrix in the form of a customizable scorecard is introduced for evaluating a Hybrid Process based on the importance of land space, capital costs, energy consumption and membrane fouling. This study provides a new perspective, looking at processes not as individual systems but as a whole utilizing strategic co-location to unlock the synergies available in the water-energy nexus for more sustainable desalination. PMID:24956940

  16. Hybrid Propulsion Demonstration Program 250K Hybrid Motor

    NASA Technical Reports Server (NTRS)

    Story, George; Zoladz, Tom; Arves, Joe; Kearney, Darren; Abel, Terry; Park, O.

    2003-01-01

    The Hybrid Propulsion Demonstration Program (HPDP) program was formed to mature hybrid propulsion technology to a readiness level sufficient to enable commercialization for various space launch applications. The goal of the HPDP was to develop and test a 250,000 pound vacuum thrust hybrid booster in order to demonstrate hybrid propulsion technology and enable manufacturing of large hybrid boosters for current and future space launch vehicles. The HPDP has successfully conducted four tests of the 250,000 pound thrust hybrid rocket motor at NASA's Stennis Space Center. This paper documents the test series.

  17. Role of synergy between wear and corrosion in degradation of materials

    NASA Astrophysics Data System (ADS)

    Azzi, Marwan

    Tribocorrosion is a term used to describe the material degradation due to the combination of electrochemical and tribological processes. Due to a synergetic effect, the material loss can be larger than the sum of the losses due to wear and corrosion acting separately. In this thesis, the synergy of wear and corrosion was investigated for different types of material, namely the Ti-6Al-4V alloy, the SS316L stainless steel coated with a thin film of Diamond Like Carbon (DLC), and the SS301 stainless steel coated with a thin film of chromium silicon nitride (CrSiN). A tribocorrosion apparatus was designed and constructed to conduct wear experiments in corrosive media. Sliding ball-on-plate configuration was used in this design, where the contact between the ball and the specimen is totally immersed in the test electrolyte. The specimen was connected to a potentiostat to control its electrochemical parameters, namely the potential and the current. Electrochemical techniques were used to control the kinetics of corrosion reactions, and therefore it was possible to assess separately the role of corrosion and wear in the total degradation of material, and to evaluate the synergy between them. For Ti-6Al-4V, it was found that the corrosion and tribocorrosion depend strongly on the structure of the material. The alpha-equiaxed microstructure with fine dispersed beta-phase exhibited the best corrosion resistance. The corrosion resistance was found to decrease when the basal plane was preferentially aligned parallel to the surface, which is attributed to a low resistance to charge transfer in the oxide films formed on this plane. On the other hand, when wear and corrosion were involved simultaneously, the oxide layer protecting the substrate against dissolution was mechanically destroyed leading to a high corrosion rate. It was found that the hardness was the most important factor determining the tribocorrosion behavior of the Ti-6Al-4V alloy; samples with high hardness

  18. Investigating synergies of data fusion and image segmentation in earth observation based rapid mapping workflows

    NASA Astrophysics Data System (ADS)

    Witharana, C.

    2013-12-01

    In humanitarian emergencies, the timeliness of data provision and the short time-window available for dispatching value-added information pose major challenges to the mapping community. We have been engaged with a continuous research effort to explore novel ways to catalyze the EO-based humanitarian crisis information retrieval chain. This paper is an exploratory study, which aimed to discover the synergies of data fusion and image segmentation in the context of EO-based rapid mapping workflows. Our approach pillared on the geographic object-based image analysis (GEOBIA) focusing on multiscale, internally-displaced persons' (IDP) camp information extraction from very high spatial resolution (VHSR) images. We applied twelve pansharpening algorithms to two subsets of a GeoEye-1 image scene that was taken over a former war-induced ephemeral settlement in Sri Lanka. A multidimensional assessment was employed to benchmark pansharpening algorithms with respect to their spectral and spatial fidelity. The multiresolution segmentation (MRS) algorithm of the eCognition Developer software served as the key algorithm in the segmentation process. The first study site was used for comparing segmentation results produced from the twelve fused products at a series of scale, shape, and compactness settings of the MRS algorithm. The segmentation quality and optimum parameter settings of the MRS algorithm were estimated by using empirical discrepancy measures. Non-parametric statistical tests were used to compare the quality of image object candidates, which were derived from the twelve pansharpened products. A wall-to-wall classification was performed based on a support vector machine (SVM) classifier to classify image objects candidates of the fused images. The second site simulated a more realistic crisis information extraction scenario where the domain expertise is crucial in segmentation and classification. We compared segmentation and classification results of the original

  19. Measure and exploitation of multisensor and multiwavelength synergy for remote sensing: 2. Application to the retrieval of atmospheric temperature and water vapor from MetOp

    NASA Astrophysics Data System (ADS)

    Aires, Filipe; Paul, Maxime; Prigent, Catherine; Rommen, BjöRn; Bouvet, Marc

    2011-01-01

    In the companion paper, classical information content (IC) analysis was used to measure the potential synergy between the microwave (MW) and infrared (IR) observations from Atmospheric Microwave Sounding Unit-A, Microwave Humidity Sounder, and Improved Atmospheric Sounding in the Infrared instruments, used to retrieve the atmospheric profiles of temperature and water vapor over ocean, under clear-sky conditions. Some limitations of IC were pointed out that questioned the reliability of this technique for synergy characterization. The goal of this second paper is to develop a methodology to measure realistic potential synergies and to construct retrieval methods able to exploit them. Three retrieval methods are considered: the k nearest neighbors, the linear regression, and the neural networks (NN). These statistical retrieval schemes are tested on an application involving IR and MW synergy. Only clear-sky, near-nadir radiances over ocean are considered. The IR/MW synergy is expected to be stronger in cloudy cases, but it will be shown that it can also be observed in clear situations. The inversion algorithms are calibrated and tested with simulated observations, without any loss of generality, using similar theoretical assumption (same radiative transfer model, observational noise, and a priori information) in order to truly compare the IC and the direct statistical retrieval approaches. Multivariate and nonlinear methods such as the NN approach show that there is a strong potential for synergy. Synergy measurement tools such as the method proposed in this study should be considered in the future for the definition of new missions: The instrument characteristics should be determined not independently, sensor by sensor, but taking into account all the instruments together as a whole observing system.

  20. Synergy of satellite and ground based observations in estimation of particulate matter in eastern China.

    PubMed

    Wu, Yerong; Guo, Jianping; Zhang, Xiaoye; Tian, Xin; Zhang, Jiahua; Wang, Yaqiang; Duan, Jing; Li, Xiaowen

    2012-09-01

    Estimating particulate matter (PM) from space is not straightforward and is mainly achieved using the aerosol optical depth (AOD) retrieved from satellite sensors. However, AOD is a columnar measure, whereas PM is a ground observation. Linking AOD and PM remains a challenge for air pollution monitoring. In this study, a back-propagation artificial neural network (BP ANN) algorithm trained with bayesian regularization that benefited from the synergy of satellite- and ground-based observations was developed to estimate PM in eastern China. Correlations between observed and estimated PM (denoted by R) during the period 2007-2008 over seven individual sites were investigated comprehensively in terms of site scale, seasonal scale, particle size, and spatio-temporal scale. With respect to site differences, the Nanning site had the best results with 80.3% of cases having a moderate or strong correlation value. Lushan and Zhengzhou followed with results of 75% and 73.8%, respectively. Furthermore, R exhibited a significant seasonal variation characterized by a maximum (80.2%) during the autumn period, whereas no obvious differences in R for various spatial scales (spatial averaging schemes of MODIS AOD) were observed. Likewise, the ratio value for daily averaging (64.7%) was found to be better than those for the two hourly temporal averaging schemes (i.e., 61.1% for HA1 and 58.3% for HA2). In addition, PM(1) estimated from the ANN algorithm developed in this study had slightly higher R values than did PM(10) and PM(2.5). The planetary boundary layer (PBL) effect on PM estimation was decreasing R with increasing height of the PBL, which is consistent with previous studies. Comparisons of observed versus estimated PM(10) mass time series implied that the ANN algorithm basically reproduced the observed PM concentration. However, PM mass at certain sites may be underestimated under the condition of high observed PM concentrations. PMID:22766424

  1. Inspiring future scientists in middle-schools through synergy between classroom learning and water cycle research

    NASA Astrophysics Data System (ADS)

    Noone, D. C.; Kellagher, E.; Berkelhammer, M. B.; Raudzens Bailey, A.; Kaushik, A.

    2012-12-01

    Water is at the core of many issues in environmental change from local to global scales, and learning about the water cycle offers students an opportunity to explore core scientific concepts and their local environment. In climate research, there are significant uncertainties in the role water plays in the climate system. Water also acts as a central theme that provides opportunities for experiential science education at all levels. The "Water Spotters" program underway at University of Colorado exploits the synergy between needs for enrichment of middle-school science education and the needs for water sample collection to provide primary data for climate research. The program takes advantage of the prominent agricultural landscape of the region in eastern Colorado, which is a poignant example of how society influences the climate through irrigation, evaporation/transpiration and run-off and whose productivity is influenced by the climate system. Both natural grasslands and alpine ecosystems in the surrounding regions serve as examples of the native landscape. In coordination with the St. Vrain Valley School District MESA (Math Engineering Science Achievement) program, middle-school students collect rain water samples that are analyzed and used as a core component of the research goals. In concert, new lessons have been developed in coordination with science teachers that emphasize both core scientific standards and application learning about the water cycle. We present the new curriculum modules developed for the program and that are distributed to middle-school teachers. The modules include original lessons and lessons with expanded original material to teach about water and water isotopes. Curriculum packages that include media resources are increasingly important to teachers. The Water Spotters program uses video to teach collection protocols and give background on the project. Weather station data from schools are disseminated online alongside the rainwater

  2. Achieving synergy between chemical oxidation and stabilization in a contaminated soil.

    PubMed

    Srivastava, Vipul J; Hudson, Jeffrey Michael; Cassidy, Daniel P

    2016-07-01

    Eight in situ solidification/stabilization (ISS) amendments were tested to promote in situ chemical oxidation (ISCO) with activated persulfate (PS) in a contaminated soil. A 3% (by weight) dose of all ISS amendments selected for this study completely activated a 1.5% dose of PS within 3 h by raising temperatures above 30 °C (heat activation) and/or increasing pH above 10.5 (alkaline activation). Heat is released by the reaction of CaO with water, and pH increases because this reaction produces Ca(OH)2. Heat activation is preferred because it generates 2 mol of oxidizing radicals per mole of PS, whereas alkaline activation releases only 1. The relative contribution of heat vs. alkaline activation increased with CaO content of the ISS amendment, which was reflected by enhanced contaminant oxidation with increasing CaO content, and was confirmed by comparing to controls promoting purely heat or alkaline (NaOH) activation. The test soil was contaminated with benzene, toluene, ethylbenzene, and xylenes (BTEX) and polycyclic aromatic hydrocarbons (PAH), particularly naphthalene (NAP). ISS-activated PS oxidized between 47% and 84% of the BTEX & NAP, and between 13% and 33% of the higher molecular weight PAH. ISS-activated PS reduced the leachability of BTEX & NAP by 76%-91% and of the 17 PAH by 83%-96%. Combined ISCO/ISS reduced contaminant leachability far than ISCO or ISS treatments alone, demonstrating the synergy that is possible with combined remedies. PMID:27088536

  3. The neurobiology of borderline personality disorder: the synergy of "nature and nurture".

    PubMed

    Pally, Regina

    2002-05-01

    The author reviews the current state of our knowledge concerning the neurobiology of borderline personality disorder (BPD). A converging body of scientific evidence indicates that patients with BPD suffer from impairments in the brain systems that regulate impulsivity, aggression, and affect. This article reviews data on the neurobiology of the symptoms of BPD, including emotional and behavioral dysregulation, identity disturbance, cognitive impairments, and interpersonal difficulties. The author first considers the evolutionary context in which BPD can develop to put the neurobiological findings in perspective, and then discusses the roles of both genetic inheritance and the environment in the development of BPD. The role of neurotransmitter systems in the development of impulsive-aggression and affective instability is reviewed. Possible neurobiological contributors to the identity disturbance seen in BPD are also described. The author then considers environmental contributions to BPD and discusses the synergy of nature and nurture in the development of BPD symptoms. Findings concerning the types of neurobiological impairments that can arise as a result of childhood neglect and abuse and other types of chronic severe stress and trauma are discussed. Finally, the author reviews studies of animal attachment models that suggest that types of maternal care can produce lifelong behavioral and physiological differences in offspring and that this effect is mediated through the regulation of gene expression. The author suggests that the large body of neuroscience research reviewed in this article suggests that, while patients with BPD may be born with innate genetic tendencies for impaired brain systems for regulating impulses and affect, the environment they find themselves born into may be critical in determining whether or not they develop the full blown syndrome of BPD. PMID:15985870

  4. Burkholderia cepacia complex Phage-Antibiotic Synergy (PAS): antibiotics stimulate lytic phage activity.

    PubMed

    Kamal, Fatima; Dennis, Jonathan J

    2015-02-01

    The Burkholderia cepacia complex (Bcc) is a group of at least 18 species of Gram-negative opportunistic pathogens that can cause chronic lung infection in cystic fibrosis (CF) patients. Bcc organisms possess high levels of innate antimicrobial resistance, and alternative therapeutic strategies are urgently needed. One proposed alternative treatment is phage therapy, the therapeutic application of bacterial viruses (or bacteriophages). Recently, some phages have been observed to form larger plaques in the presence of sublethal concentrations of certain antibiotics; this effect has been termed phage-antibiotic synergy (PAS). Those reports suggest that some antibiotics stimulate increased production of phages under certain conditions. The aim of this study is to examine PAS in phages that infect Burkholderia cenocepacia strains C6433 and K56-2. Bcc phages KS12 and KS14 were tested for PAS, using 6 antibiotics representing 4 different drug classes. Of the antibiotics tested, the most pronounced effects were observed for meropenem, ciprofloxacin, and tetracycline. When grown with subinhibitory concentrations of these three antibiotics, cells developed a chain-like arrangement, an elongated morphology, and a clustered arrangement, respectively. When treated with progressively higher antibiotic concentrations, both the sizes of plaques and phage titers increased, up to a maximum. B. cenocepacia K56-2-infected Galleria mellonella larvae treated with phage KS12 and low-dose meropenem demonstrated increased survival over controls treated with KS12 or antibiotic alone. These results suggest that antibiotics can be combined with phages to stimulate increased phage production and/or activity and thus improve the efficacy of bacterial killing. PMID:25452284

  5. Discovery of Drug Synergies in Gastric Cancer Cells Predicted by Logical Modeling

    PubMed Central

    Flobak, Åsmund; Baudot, Anaïs; Remy, Elisabeth; Thommesen, Liv; Thieffry, Denis; Kuiper, Martin; Lægreid, Astrid

    2015-01-01

    Discovery of efficient anti-cancer drug combinations is a major challenge, since experimental testing of all possible combinations is clearly impossible. Recent efforts to computationally predict drug combination responses retain this experimental search space, as model definitions typically rely on extensive drug perturbation data. We developed a dynamical model representing a cell fate decision network in the AGS gastric cancer cell line, relying on background knowledge extracted from literature and databases. We defined a set of logical equations recapitulating AGS data observed in cells in their baseline proliferative state. Using the modeling software GINsim, model reduction and simulation compression techniques were applied to cope with the vast state space of large logical models and enable simulations of pairwise applications of specific signaling inhibitory chemical substances. Our simulations predicted synergistic growth inhibitory action of five combinations from a total of 21 possible pairs. Four of the predicted synergies were confirmed in AGS cell growth real-time assays, including known effects of combined MEK-AKT or MEK-PI3K inhibitions, along with novel synergistic effects of combined TAK1-AKT or TAK1-PI3K inhibitions. Our strategy reduces the dependence on a priori drug perturbation experimentation for well-characterized signaling networks, by demonstrating that a model predictive of combinatorial drug effects can be inferred from background knowledge on unperturbed and proliferating cancer cells. Our modeling approach can thus contribute to preclinical discovery of efficient anticancer drug combinations, and thereby to development of strategies to tailor treatment to individual cancer patients. PMID:26317215

  6. Essential Oils in Food Preservation: Mode of Action, Synergies, and Interactions with Food Matrix Components

    PubMed Central

    Hyldgaard, Morten; Mygind, Tina; Meyer, Rikke Louise

    2012-01-01

    Essential oils are aromatic and volatile liquids extracted from plants. The chemicals in essential oils are secondary metabolites, which play an important role in plant defense as they often possess antimicrobial properties. The interest in essential oils and their application in food preservation has been amplified in recent years by an increasingly negative consumer perception of synthetic preservatives. Furthermore, food-borne diseases are a growing public health problem worldwide, calling for more effective preservation strategies. The antibacterial properties of essential oils and their constituents have been documented extensively. Pioneering work has also elucidated the mode of action of a few essential oil constituents, but detailed knowledge about most of the compounds’ mode of action is still lacking. This knowledge is particularly important to predict their effect on different microorganisms, how they interact with food matrix components, and how they work in combination with other antimicrobial compounds. The main obstacle for using essential oil constituents as food preservatives is that they are most often not potent enough as single components, and they cause negative organoleptic effects when added in sufficient amounts to provide an antimicrobial effect. Exploiting synergies between several compounds has been suggested as a solution to this problem. However, little is known about which interactions lead to synergistic, additive, or antagonistic effects. Such knowledge could contribute to design of new and more potent antimicrobial blends, and to understand the interplay between the constituents of crude essential oils. The purpose of this review is to provide an overview of current knowledge about the antibacterial properties and antibacterial mode of action of essential oils and their constituents, and to identify research avenues that can facilitate implementation of essential oils as natural preservatives in foods. PMID:22291693

  7. Augmented reality and photogrammetry: A synergy to visualize physical and virtual city environments

    NASA Astrophysics Data System (ADS)

    Portalés, Cristina; Lerma, José Luis; Navarro, Santiago

    2010-01-01

    Close-range photogrammetry is based on the acquisition of imagery to make accurate measurements and, eventually, three-dimensional (3D) photo-realistic models. These models are a photogrammetric product per se. They are usually integrated into virtual reality scenarios where additional data such as sound, text or video can be introduced, leading to multimedia virtual environments. These environments allow users both to navigate and interact on different platforms such as desktop PCs, laptops and small hand-held devices (mobile phones or PDAs). In very recent years, a new technology derived from virtual reality has emerged: Augmented Reality (AR), which is based on mixing real and virtual environments to boost human interactions and real-life navigations. The synergy of AR and photogrammetry opens up new possibilities in the field of 3D data visualization, navigation and interaction far beyond the traditional static navigation and interaction in front of a computer screen. In this paper we introduce a low-cost outdoor mobile AR application to integrate buildings of different urban spaces. High-accuracy 3D photo-models derived from close-range photogrammetry are integrated in real (physical) urban worlds. The augmented environment that is presented herein requires for visualization a see-through video head mounted display (HMD), whereas user's movement navigation is achieved in the real world with the help of an inertial navigation sensor. After introducing the basics of AR technology, the paper will deal with real-time orientation and tracking in combined physical and virtual city environments, merging close-range photogrammetry and AR. There are, however, some software and complex issues, which are discussed in the paper.

  8. Hard Disk/Solid State Drive Synergy in Support of Data-Intensive Computing

    SciTech Connect

    Liu,Ke; Jiang, Song; Davis, Kei

    2012-07-19

    Data-intensive applications are becoming increasingly common in high-performance computing. Examples include combustion simulation, human genome analysis, and satellite image processing. Efficient access of data sets is critical to the performance of these applications. Because of the size of the data today's economically feasible approach is to store the data files on an array of hard disks or data servers equipped with hard disks and managed by a parallel file system such as PVFS or Lustre wherein the data is striped over a (large) number of disks for high aggregate I/O throughout. With file striping, a request for a segment of logically contiguous file space is decomposed into multiple sub-requests, each to a different server. While the data unit for this striping is usually reasonably large to benefit disk efficiency, the first and/or last sub-requests can be much smaller than the striping unit if the request does not align with the striping pattern, severely compromising hard disk efficiency and thus application performance. We propose to exploit solid state drives (SSD), whose efficiency is much less sensitive to small random accesses, to enable the alignment of requests to disk with the data striping pattern. In this scheme hard disks mainly serve large, aligned, sequential requests, with SSDs serving small or unaligned requests, thus respecting the relative cost, performance, and durability characteristics of the two media, and thereby achieving synergy in performance/cost. We will describe the design of the proposed scheme, its implementation on CCS-7's Darwin cluster, and performance results.

  9. Study of atmospheric parameters measurements using MM-wave radar in synergy with LITE-2

    NASA Technical Reports Server (NTRS)

    Andrawis, Madeleine Y.

    1994-01-01

    The Lidar In-Space Technology Experiment, (LITE), has been developed, designed, and built by NASA Langley Research Center, to be flown on the space shuttle 'Discovery' on September 9, 1994. Lidar, which stands for light detecting and ranging, is a radar system that uses short pulses of laser light instead of radio waves in the case of the common radar. This space-based lidar offers atmospheric measurements of stratospheric and tropospheric aerosols, the planetary boundary layer, cloud top heights, and atmospheric temperature and density in the 10-40 km altitude range. A study is being done on the use, advantages, and limitations of a millimeterwave radar to be utilized in synergy with the Lidar system, for the LITE-2 experiment to be flown on a future space shuttle mission. The lower atmospheric attenuation, compared to infrared and optical frequencies, permits the millimeter-wave signals to penetrate through the clouds and measure multi-layered clouds, cloud thickness, and cloud-base height. These measurements would provide a useful input to radiation computations used in the operational numerical weather prediction models, and for forecasting. High power levels, optimum modulation, data processing, and high antenna gain are used to increase the operating range, while space environment, radar tradeoffs, and power availability are considered. Preliminary, numerical calculations are made, using the specifications of an experimental system constructed at Georgia Tech. The noncoherent 94 GHz millimeter-wave radar system has a pulsed output with peak value of 1 kW. The backscatter cross section of the particles to be measured, that are present in the volume covered by the beam footprint, is also studied.

  10. Searching for Drug Synergy in Complex Dose–Response Landscapes Using an Interaction Potency Model

    PubMed Central

    Yadav, Bhagwan; Wennerberg, Krister; Aittokallio, Tero; Tang, Jing

    2015-01-01

    Rational design of multi-targeted drug combinations is a promising strategy to tackle the drug resistance problem for many complex disorders. A drug combination is usually classified as synergistic or antagonistic, depending on the deviation of the observed combination response from the expected effect calculated based on a reference model of non-interaction. The existing reference models were proposed originally for low-throughput drug combination experiments, which make the model assumptions often incompatible with the complex drug interaction patterns across various dose pairs that are typically observed in large-scale dose–response matrix experiments. To address these limitations, we proposed a novel reference model, named zero interaction potency (ZIP), which captures the drug interaction relationships by comparing the change in the potency of the dose–response curves between individual drugs and their combinations. We utilized a delta score to quantify the deviation from the expectation of zero interaction, and proved that a delta score value of zero implies both probabilistic independence and dose additivity. Using data from a large-scale anticancer drug combination experiment, we demonstrated empirically how the ZIP scoring approach captures the experimentally confirmed drug synergy while keeping the false positive rate at a low level. Further, rather than relying on a single parameter to assess drug interaction, we proposed the use of an interaction landscape over the full dose–response matrix to identify and quantify synergistic and antagonistic dose regions. The interaction landscape offers an increased power to differentiate between various classes of drug combinations, and may therefore provide an improved means for understanding their mechanisms of action toward clinical translation. PMID:26949479

  11. Development of ATLID-MSI synergy for retrieving the vertical profiles of aerosol components

    NASA Astrophysics Data System (ADS)

    Kudo, R.; Nishizawa, T.; Higurashi, A.; Sugimoto, N.; Oikawa, E.

    2014-12-01

    EarthCARE is an earth observation satellite and will be launched in 2016. Using its two sensors, ATLID (High spectral resolution lidar) and MSI (Multi-spectral imager), we are developing the synergy algorithm to retrieve the vertical profiles of extinction coefficients at 355 nm of four aerosol components (Water-soluble, black carbon, dust, and sea-salt particles), and the column mean of mode radii of water-soluble and dust particles. The ATLID data are extinction coefficient, backscatter coefficient, and depolarization ratio for total aerosols at 355 nm. The MSI data are radiances at 670 and 865 nm. The dry volume concentrations of four aerosol components at each altitude and the mode radii of water-soluble and dust particles in the column are simultaneously optimized to ATLID and MSI data by the gauss newton method. After the optimization, the vertical profiles of the extinction coefficient at 355 nm of four aerosol components are obtained. The size distributions of four aerosol components are assumed to be a lognormal distribution. The refractive indices of four aerosol components are given from previously observational studies. The humidity growth is considered for water-soluble and sea-salt particles. The volume concentration and the mode radius of the sea-salt particle are parameterized using the surface wind speed on the ocean. We assumed that the shape of the water-soluble, black carbon, and sea-salt particles are spherical, and the shape of the dust particle is spheroidal. We tested the algorithm using the ATLID and MSI data simulated using clean, dust-transported, and smoke-transported aerosols. The extinction coefficients of each component at 355 nm are retrieved well. The mode radius of water-soluble and dust particles were somehow overestimated.

  12. Molecular mechanisms of corticosteroid synergy with thyroid hormone during tadpole metamorphosis.

    PubMed

    Bonett, Ronald M; Hoopfer, Eric D; Denver, Robert J

    2010-09-01

    Corticosteroids (CS) act synergistically with thyroid hormone (TH) to accelerate amphibian metamorphosis. Earlier studies showed that CS increase nuclear 3,5,3'-triiodothyronine (T(3)) binding capacity in tadpole tail, and 5' deiodinase activity in tadpole tissues, increasing the generation of T(3) from thyroxine (T(4)). In the present study we investigated CS synergy with TH by analyzing expression of key genes involved in TH and CS signaling using tadpole tail explant cultures, prometamorphic tadpoles, and frog tissue culture cells (XTC-2 and XLT-15). Treatment of tail explants with T(3) at 100 nM, but not at 10 nM caused tail regression. Corticosterone (CORT) at three doses (100, 500 and 3400 nM) had no effect or increased tail size. T(3) at 10 nM plus CORT caused tails to regress similar to 100 nM T(3). Thyroid hormone receptor beta (TRbeta) mRNA was synergistically upregulated by T(3) plus CORT in tail explants, tail and brain in vivo, and tissue culture cells. The activating 5' deiodinase type 2 (D2) mRNA was induced by T(3) and CORT in tail explants and tail in vivo. Thyroid hormone increased expression of glucocorticoid (GR) and mineralocorticoid receptor (MR) mRNAs. Our findings support that the synergistic actions of TH and CS in metamorphosis occur at the level of expression of genes for TRbeta and D2, enhancing tissue sensitivity to TH. Concurrently, TH enhances tissue sensitivity to CS by upregulating GR and MR. Environmental stressors can modulate the timing of tadpole metamorphosis in part by CS enhancing the response of tadpole tissues to the actions of TH. PMID:20338173

  13. High chlorpyrifos resistance in Culex pipiens mosquitoes: strong synergy between resistance genes.

    PubMed

    Alout, H; Labbé, P; Berthomieu, A; Makoundou, P; Fort, P; Pasteur, N; Weill, M

    2016-02-01

    We investigated the genetic determinism of high chlorpyrifos resistance (HCR), a phenotype first described in 1999 in Culex pipiens mosquitoes surviving chlorpyrifos doses ⩾1 mg l(-1) and more recently found in field samples from Tunisia, Israel or Indian Ocean islands. Through chlorpyrifos selection, we selected several HCR strains that displayed over 10 000-fold resistance. All strains were homozygous for resistant alleles at two main loci: the ace-1 gene, with the resistant ace-1(R) allele expressing the insensitive G119S acetylcholinesterase, and a resistant allele of an unknown gene (named T) linked to the sex and ace-2 genes. We constructed a strain carrying only the T-resistant allele and studied its resistance characteristics. By crossing this strain with strains harboring different alleles at the ace-1 locus, we showed that the resistant ace-1(R) and the T alleles act in strong synergy, as they elicited a resistance 100 times higher than expected from a simple multiplicative effect. This effect was specific to chlorpyrifos and parathion and was not affected by synergists. We also examined how HCR was expressed in strains carrying other ace-1-resistant alleles, such as ace-1(V) or the duplicated ace-1(D) allele, currently spreading worldwide. We identified two major parameters that influenced the level of resistance: the number and the nature of the ace-1-resistant alleles and the number of T alleles. Our data fit a model that predicts that the T allele acts by decreasing chlorpyrifos concentration in the compartment targeted in insects. PMID:26463842

  14. Absence of synergy for monosynaptic Group I inputs between abdominal and internal intercostal motoneurons

    PubMed Central

    Ford, T. W.; Meehan, C. F.

    2014-01-01

    Internal intercostal and abdominal motoneurons are strongly coactivated during expiration. We investigated whether that synergy was paralleled by synergistic Group I reflex excitation. Intracellular recordings were made from motoneurons of the internal intercostal nerve of T8 in anesthetized cats, and the specificity of the monosynaptic connections from afferents in each of the two main branches of this nerve was investigated. Motoneurons were shown by antidromic excitation to innervate three muscle groups: external abdominal oblique [EO; innervated by the lateral branch (Lat)], the region of the internal intercostal muscle proximal to the branch point (IIm), and muscles innervated from the distal remainder (Dist). Strong specificity was observed, only 2 of 54 motoneurons showing excitatory postsynaptic potentials (EPSPs) from both Lat and Dist. No EO motoneurons showed an EPSP from Dist, and no IIm motoneurons showed one from Lat. Expiratory Dist motoneurons fell into two groups. Those with Dist EPSPs and none from Lat (group A) were assumed to innervate distal internal intercostal muscle. Those with Lat EPSPs (group B) were assumed to innervate abdominal muscle (transversus abdominis or rectus abdominis). Inspiratory Dist motoneurons (assumed to innervate interchondral muscle) showed Dist EPSPs. Stimulation of dorsal ramus nerves gave EPSPs in 12 instances, 9 being in group B Dist motoneurons. The complete absence of heteronymous monosynaptic Group I reflex excitation between muscles that are synergistically activated in expiration leads us to conclude that such connections from muscle spindle afferents of the thoracic nerves have little role in controlling expiratory movements but, where present, support other motor acts. PMID:24920027

  15. Study of atmospheric parameters measurements using MM-wave radar in synergy with LITE-2

    NASA Astrophysics Data System (ADS)

    Andrawis, Madeleine Y.

    1994-12-01

    The Lidar In-Space Technology Experiment, (LITE), has been developed, designed, and built by NASA Langley Research Center, to be flown on the space shuttle 'Discovery' on September 9, 1994. Lidar, which stands for light detecting and ranging, is a radar system that uses short pulses of laser light instead of radio waves in the case of the common radar. This space-based lidar offers atmospheric measurements of stratospheric and tropospheric aerosols, the planetary boundary layer, cloud top heights, and atmospheric temperature and density in the 10-40 km altitude range. A study is being done on the use, advantages, and limitations of a millimeterwave radar to be utilized in synergy with the Lidar system, for the LITE-2 experiment to be flown on a future space shuttle mission. The lower atmospheric attenuation, compared to infrared and optical frequencies, permits the millimeter-wave signals to penetrate through the clouds and measure multi-layered clouds, cloud thickness, and cloud-base height. These measurements would provide a useful input to radiation computations used in the operational numerical weather prediction models, and for forecasting. High power levels, optimum modulation, data processing, and high antenna gain are used to increase the operating range, while space environment, radar tradeoffs, and power availability are considered. Preliminary, numerical calculations are made, using the specifications of an experimental system constructed at Georgia Tech. The noncoherent 94 GHz millimeter-wave radar system has a pulsed output with peak value of 1 kW. The backscatter cross section of the particles to be measured, that are present in the volume covered by the beam footprint, is also studied.

  16. Hybrid baryons in QCD

    DOE PAGESBeta

    Dudek, Jozef J.; Edwards, Robert G.

    2012-03-21

    In this study, we present the first comprehensive study of hybrid baryons using lattice QCD methods. Using a large basis of composite QCD interpolating fields we extract an extensive spectrum of baryon states and isolate those of hybrid character using their relatively large overlap onto operators which sample gluonic excitations. We consider the spectrum of Nucleon and Delta states at several quark masses finding a set of positive parity hybrid baryons with quantum numbersmore » $$N_{1/2^+},\\,N_{1/2^+},\\,N_{3/2^+},\\, N_{3/2^+},\\,N_{5/2^+},\\,$$ and $$\\Delta_{1/2^+},\\, \\Delta_{3/2^+}$$ at an energy scale above the first band of `conventional' excited positive parity baryons. This pattern of states is compatible with a color octet gluonic excitation having $$J^{P}=1^{+}$$ as previously reported in the hybrid meson sector and with a comparable energy scale for the excitation, suggesting a common bound-state construction for hybrid mesons and baryons.« less

  17. Research on Hybrid Vehicle Drivetrain

    NASA Astrophysics Data System (ADS)

    Xie, Zhongzhi

    Hybrid cars as a solution to energy saving, emission reduction measures, have received widespread attention. Motor drive system as an important part of the hybrid vehicles as an important object of study. Based on the hybrid electric vehicle powertrain control system for permanent magnet synchronous motor as the object of study. Can be applied to hybrid car compares the characteristics of traction motors, chose permanent magnet synchronous Motors as drive motors for hybrid vehicles. Building applications in hybrid cars in MATLAB/Simulink simulation model of permanent-magnet synchronous motor speed control system and analysis of simulation results.

  18. Hybridization schemes for clusters

    NASA Astrophysics Data System (ADS)

    Wales, David J.

    The concept of an optimum hybridization scheme for cluster compounds is developed with particular reference to electron counting. The prediction of electron counts for clusters and the interpretation of the bonding is shown to depend critically upon the presumed hybridization pattern of the cluster vertex atoms. This fact has not been properly appreciated in previous work, particularly in applications of Stone's tensor surface harmonic (TSH) theory, but is found to be a useful tool when dealt with directly. A quantitative definition is suggested for the optimum cluster hybridization pattern based directly upon the ease of interpretation of the molecular orbitals, and results are given for a range of species. The relationship of this scheme to the detailed cluster geometry is described using Löwdin's partitioned perturbation theory, and the success and range of application of TSH theory are discussed.

  19. Ames Hybrid Combustion Facility

    NASA Technical Reports Server (NTRS)

    Zilliac, Greg; Karabeyoglu, Mustafa A.; Cantwell, Brian; Hunt, Rusty; DeZilwa, Shane; Shoffstall, Mike; Soderman, Paul T.; Bencze, Daniel P. (Technical Monitor)

    2003-01-01

    The report summarizes the design, fabrication, safety features, environmental impact, and operation of the Ames Hybrid-Fuel Combustion Facility (HCF). The facility is used in conducting research into the scalability and combustion processes of advanced paraffin-based hybrid fuels for the purpose of assessing their applicability to practical rocket systems. The facility was designed to deliver gaseous oxygen at rates between 0.5 and 16.0 kg/sec to a combustion chamber operating at pressures ranging from 300 to 900. The required run times were of the order of 10 to 20 sec. The facility proved to be robust and reliable and has been used to generate a database of regression-rate measurements of paraffin at oxygen mass flux levels comparable to those of moderate-sized hybrid rocket motors.

  20. Hybridization in geese: a review.

    PubMed

    Ottenburghs, Jente; van Hooft, Pim; van Wieren, Sipke E; Ydenberg, Ronald C; Prins, Herbert H T

    2016-01-01

    The high incidence of hybridization in waterfowl (ducks, geese and swans) makes this bird group an excellent study system to answer questions related to the evolution and maintenance of species boundaries. However, knowledge on waterfowl hybridization is biased towards ducks, with a large knowledge gap in geese. In this review, we assemble the available information on hybrid geese by focusing on three main themes: (1) incidence and frequency, (2) behavioural mechanisms leading to hybridization, and (3) hybrid fertility. Hybridization in geese is common on a species-level, but rare on a per-individual level. An overview of the different behavioural mechanisms indicates that forced extra-pair copulations and interspecific nest parasisitm can both lead to hybridization. Other sources of hybrids include hybridization in captivity and vagrant geese, which may both lead to a scarcity of conspecifics. The different mechanisms are not mutually exclusive and it is currently not possible to discriminate between the different mechanisms without quantitative data. Most hybrid geese are fertile; only in crosses between distantly related species do female hybrids become sterile. This fertility pattern, which is in line with Haldane's Rule, may facilitate interspecific gene flow between closely related species. The knowledge on hybrid geese should be used, in combination with the information available on hybridization in ducks, to study the process of avian speciation. PMID:27182276

  1. Hybridization of natural systems with advanced treatment processes for organic micropollutant removals: new concepts in multi-barrier treatment.

    PubMed

    Sudhakaran, Sairam; Maeng, Sung Kyu; Amy, Gary

    2013-07-01

    Organic micropollutants (OMPs) represent a major constraint in drinking water supply. In the past, emphasis has been on individual treatment processes comprising conventional treatment (coagulation, sedimentation, and filtration) followed by advanced treatment processes (adsorption, ion-exchange, oxidation, and membrane separation). With the depletion of water resources and high demand for power and chemical usage, efforts need to be made to judiciously use advanced treatment processes. There is a new interest in multiple barriers with synergies in which two coupled processes can function as a hybrid process. Within the context of this paper, the hybrid processes include a natural treatment process coupled with an advanced process. Pilot/full-scale studies have shown efficient removal of OMPs by these hybrid processes. With this hybridization, the usage of resources such as power and chemicals can be reduced. In this study, coupling/hybridization of aquifer recharge and recovery (ARR) with oxidation (O3), advanced oxidation process which involves OH radicals (AOP), nanofiltration (NF), reverse osmosis (RO) and granular activated carbon (GAC) adsorption for OMP removal was studied. O3 or AOP as a pre-treatment and GAC, NF, RO, or UV/chlorination as a post-treatment to ARR was studied. NF can be replaced by RO for removal of OMPs since studies have shown similar performance of NF to RO for removal of many OMPs, thereby reducing costs and providing a more sustainable approach. PMID:23664475

  2. Smart hybrid rotary damper

    NASA Astrophysics Data System (ADS)

    Yang, C. S. Walter; DesRoches, Reginald

    2014-03-01

    This paper develops a smart hybrid rotary damper using a re-centering smart shape memory alloy (SMA) material as well as conventional energy-dissipating metallic plates that are easy to be replaced. The ends of the SMA and steel plates are inserted in the hinge. When the damper rotates, all the plates bend, providing energy dissipating and recentering characteristics. Such smart hybrid rotary dampers can be installed in structures to mitigate structural responses and to re-center automatically. The damaged energy-dissipating plates can be easily replaced promptly after an external excitation, reducing repair time and costs. An OpenSEES model of a smart hybrid rotary was established and calibrated to reproduce the realistic behavior measured from a full-scale experimental test. Furthermore, the seismic performance of a 3-story moment resisting model building with smart hybrid rotary dampers designed for downtown Los Angeles was also evaluated in the OpenSEES structural analysis software. Such a smart moment resisting frame exhibits perfect residual roof displacement, 0.006", extremely smaller than 18.04" for the conventional moment resisting frame subjected to a 2500 year return period ground motion for the downtown LA area (an amplified factor of 1.15 on Kobe earthquake). The smart hybrid rotary dampers are also applied into an eccentric braced steel frame, which combines a moment frame system and a bracing system. The results illustrate that adding smart hybrid rotaries in this braced system not only completely restores the building after an external excitation, but also significantly reduces peak interstory drifts.

  3. Synergy between Common γ Chain Family Cytokines and IL-18 Potentiates Innate and Adaptive Pathways of NK Cell Activation

    PubMed Central

    Nielsen, Carolyn M.; Wolf, Asia-Sophia; Goodier, Martin R.; Riley, Eleanor M.

    2016-01-01

    Studies to develop cell-based therapies for cancer and other diseases have consistently shown that purified human natural killer (NK) cells secrete cytokines and kill target cells after in vitro culture with high concentrations of cytokines. However, these assays poorly reflect the conditions that are likely to prevail in vivo in the early stages of an infection and have been carried out in a wide variety of experimental systems, which has led to contradictions within the literature. We have conducted a detailed kinetic and dose–response analysis of human NK cell responses to low concentrations of IL-12, IL-15, IL-18, IL-21, and IFN-α, alone and in combination, and their potential to synergize with IL-2. We find that very low concentrations of both innate and adaptive common γ chain cytokines synergize with equally low concentrations of IL-18 to drive rapid and potent NK cell CD25 and IFN-γ expression; IL-18 and IL-2 reciprocally sustain CD25 and IL-18Rα expression in a positive feedback loop; and IL-18 synergizes with FcγRIII (CD16) signaling to augment antibody-dependent cellular cytotoxicity. These data indicate that NK cells can be rapidly activated by very low doses of innate cytokines and that the common γ chain cytokines have overlapping but distinct functions in combination with IL-18. Importantly, synergy between multiple signaling pathways leading to rapid NK cell activation at very low cytokine concentrations has been overlooked in prior studies focusing on single cytokines or simple combinations. Moreover, although the precise common γ chain cytokines available during primary and secondary infections may differ, their synergy with both IL-18 and antigen–antibody immune complexes underscores their contribution to NK cell activation during innate and adaptive responses. IL-18 signaling potentiates NK cell effector function during innate and adaptive immune responses by synergy with IL-2, IL-15, and IL-21 and immune complexes. PMID:27047490

  4. Dual Dimensionality Reduction Reveals Independent Encoding of Motor Features in a Muscle Synergy for Insect Flight Control

    PubMed Central

    Sponberg, Simon; Daniel, Thomas L.; Fairhall, Adrienne L.

    2015-01-01

    What are the features of movement encoded by changing motor commands? Do motor commands encode movement independently or can they be represented in a reduced set of signals (i.e. synergies)? Motor encoding poses a computational and practical challenge because many muscles typically drive movement, and simultaneous electrophysiology recordings of all motor commands are typically not available. Moreover, during a single locomotor period (a stride or wingstroke) the variation in movement may have high dimensionality, even if only a few discrete signals activate the muscles. Here, we apply the method of partial least squares (PLS) to extract the encoded features of movement based on the cross-covariance of motor signals and movement. PLS simultaneously decomposes both datasets and identifies only the variation in movement that relates to the specific muscles of interest. We use this approach to explore how the main downstroke flight muscles of an insect, the hawkmoth Manduca sexta, encode torque during yaw turns. We simultaneously record muscle activity and turning torque in tethered flying moths experiencing wide-field visual stimuli. We ask whether this pair of muscles acts as a muscle synergy (a single linear combination of activity) consistent with their hypothesized function of producing a left-right power differential. Alternatively, each muscle might individually encode variation in movement. We show that PLS feature analysis produces an efficient reduction of dimensionality in torque variation within a wingstroke. At first, the two muscles appear to behave as a synergy when we consider only their wingstroke-averaged torque. However, when we consider the PLS features, the muscles reveal independent encoding of torque. Using these features we can predictably reconstruct the variation in torque corresponding to changes in muscle activation. PLS-based feature analysis provides a general two-sided dimensionality reduction that reveals encoding in high dimensional

  5. Epigenetic bivalent marking is permissive to the synergy of HDAC and PARP inhibitors on TXNIP expression in breast cancer cells.

    PubMed

    Baldan, Federica; Mio, Catia; Lavarone, Elisa; Di Loreto, Carla; Puglisi, Fabio; Damante, Giuseppe; Puppin, Cinzia

    2015-05-01

    Studies on stem cell differentiation led to the identification of paused genes, characterized by the contemporary presence of both activator and repressor epigenetic markers (bivalent marking). TXNIP is an oncosuppressor gene the expression of which was reduced in breast cancer. In the present study, we evaluated whether the concept of epigenetic bivalent marking can be applied to TXNIP gene in breast cancer cells. Using chromatin immunoprecipitation (ChIP), three histone modifications were investigated: two associated with transcriptional activation, lysines 9-14 acetylation of H3 histone (H3K9K14ac) and lysine 4 trimethylation of H3 histone (H3K4me3), and one associated with transcriptional silencing, lysine 27 trimethylation of H3 histone (H3K27me3). According to the bivalent marking model, TXNIP gene appears to be paused in MDA157 cells (markers of active and repressed transcription are present), but are definitively silenced in MDA468 cells (presence of only markers of transcription repression). This was proven by evaluating TXNIP mRNA and protein levels after the treatment of cell lines with a histone deacetylase inhibitor (SAHA) and a poly-ADP-ribose polymerases inhibitor (PJ34). In MDA157 cells, SAHA and PJ34 showed a synergistic effect: a large increment was observed in TXNIP mRNA and protein levels. By contrast, in MDA468 cells, synergy between the two compounds was not observed. Therefore, the pausing epigenetic signature was permissive for synergy between SAHA and PJ34 on TXNIP gene expression. The synergy between SAHA and PJ34 on TXNIP expression was associated with variation in cell viability and apoptosis. In MDA157 cells, but not in MDA468 cells, combined treatment of SAHA and PJ34 induced a decrease in cell viability and an increase of apoptosis. Thus, our data support the hypothesis that TXNIP is an effective target for the treatment of breast cancer. PMID:25812606

  6. Inhibition of cholesterol metabolism underlies synergy between mTOR pathway inhibition and chloroquine in bladder cancer cells

    PubMed Central

    King, M A; Ganley, I G; Flemington, V

    2016-01-01

    Mutations to fibroblast growth factor receptor 3 (FGFR3) and phosphatase and tensin homologue (PTEN) signalling pathway components (for example, PTEN loss, PIK3CA, AKT1, TSC1/2) are common in bladder cancer, yet small-molecule inhibitors of these nodes (FGFR/PTENi) show only modest activity in preclinical models. As activation of autophagy is proposed to promote survival under FGFR/PTENi, we have investigated this relationship in a panel of 18 genetically diverse bladder cell lines. We found that autophagy inhibition does not sensitise bladder cell lines to FGFR/PTENi, but newly identify an autophagy-independent cell death synergy in FGFR3-mutant cell lines between mTOR (mammalian target of rapamycin) pathway inhibitors and chloroquine (CQ)—an anti-malarial drug used as a cancer therapy adjuvant in over 30 clinical trials. The mechanism of synergy is consistent with lysosomal cell death (LCD), including cathepsin-driven caspase activation, and correlates with suppression of cSREBP1 and cholesterol biosynthesis in sensitive cell lines. Remarkably, loss of viability can be rescued by saturating cellular membranes with cholesterol or recapitulated by statin-mediated inhibition, or small interfering RNA knockdown, of enzymes regulating cholesterol metabolism. Modulation of CQ-induced cell death by atorvastatin and cholesterol is reproduced across numerous cell lines, confirming a novel and fundamental role for cholesterol biosynthesis in regulating LCD. Thus, we have catalogued the molecular events underlying cell death induced by CQ in combination with an anticancer therapeutic. Moreover, by revealing a hitherto unknown aspect of lysosomal biology under stress, we propose that suppression of cholesterol metabolism in cancer cells should elicit synergy with CQ and define a novel approach to future cancer treatments. PMID:26853465

  7. Hybrid nonlocality distillation

    NASA Astrophysics Data System (ADS)

    Wu, Keng-Shuo; Hsu, Li-Yi

    2013-08-01

    In this Letter, we introduce the notion of hybrid nonlocality distillation, in which different nonlocal boxes are exploited for nonlocality distillation. Here, we quantify the nonlocality using the violation degree of either the Clauser-Horne-Shimony-Holt inequality or the I3322 inequality. Our study shows that hybrid nonlocality distillation can outperform nonlocality distillation using copies of single nonlocal boxes. In particular, more nonlocality of undistillable boxes can be activated with the assistance of distillable boxes. Equivalently, distillable boxes can achieve more nonlocality with the assistance of undistillable boxes.

  8. Diagnostics for hybrid reactors

    NASA Astrophysics Data System (ADS)

    Orsitto, Francesco Paolo

    2012-06-01

    The Hybrid Reactor(HR) can be considered an attractive actinide-burner or a fusion assisted transmutation for destruction of transuranic(TRU) nuclear waste. The hybrid reactor has two important subsystems: the tokamak neutron source and the blanket which includes a fuel zone where the TRU are placed and a tritium breeding zone. The diagnostic system for a HR must be as simple and robust as possible to monitor and control the plasma scenario, guarantee the protection of the machine and monitor the transmutation.

  9. Hybridized polymer matrix composite

    NASA Technical Reports Server (NTRS)

    Stern, B. A.; Visser, T.

    1981-01-01

    Under certain conditions of combined fire and impact, graphite fibers are released to the atmosphere by graphite fiber composites. The retention of graphite fibers in these situations is investigated. Hybrid combinations of graphite tape and cloth, glass cloth, and resin additives are studied with resin systems. Polyimide resins form the most resistant composites and resins based on simple novolac epoxies the least resistant of those tested. Great improvement in the containment of the fibers is obtained in using graphite/glass hybrids, and nearly complete prevention of individual fiber release is made possible by the use of resin additives.

  10. Diagnostics for hybrid reactors

    SciTech Connect

    Orsitto, Francesco Paolo

    2012-06-19

    The Hybrid Reactor(HR) can be considered an attractive actinide-burner or a fusion assisted transmutation for destruction of transuranic(TRU) nuclear waste. The hybrid reactor has two important subsystems: the tokamak neutron source and the blanket which includes a fuel zone where the TRU are placed and a tritium breeding zone. The diagnostic system for a HR must be as simple and robust as possible to monitor and control the plasma scenario, guarantee the protection of the machine and monitor the transmutation.

  11. Hybrid network intrusion detection

    NASA Astrophysics Data System (ADS)

    Tahmoush, David

    2014-05-01

    We report on a machine learning classifier that can be used to discover the patterns hidden within large networking data flows. It utilizes an existing intrusion detection system (IDS) as an oracle to learn a faster, less resource intensive normalcy classifier as a front-end to a hybrid network IDS. This system has the capability to recognize new attacks that are similar to known attack signatures. It is also more highly scalable and distributable than the signature-based IDS. The new hybrid design also allows distributed updates and retraining of the normalcy classifier to stay up-to-date with current threats.

  12. A Synergy Effect of Trisodium Phosphate and Ethanol on Inactivation of Murine Norovirus 1 on Lettuce and Bell Pepper.

    PubMed

    Kim, Eun-Jin; Lee, Young-Duck; Kim, Kwang-Yup; Park, Jong-Hyun

    2015-12-28

    The synergy effect of trisodium phosphate (TSP) and ethanol against murine norovirus 1 (MNV-1), as a surrogate for human noroviruses, on fresh produces was evaluated. More than 2% (w/v) of TSP effectively inactivated MNV-1. The single treatment of 1% TSP or 30% ethanol for 30 min was not effective on MNV-1; however, cotreatment showed inactivation of MNV-1 on stainless steel and the produces of lettuce and bell pepper under 15 min. The results suggest that cotreatment of TSP and ethanol at a low concentration and a short time of exposure might be useful for the reduction of norovirus in some produce. PMID:26323270

  13. A Mathematical Approach to Hybridization

    ERIC Educational Resources Information Center

    Matthews, P. S. C.; Thompson, J. J.

    1975-01-01

    Presents an approach to hybridization which exploits the similarities between the algebra of wave functions and vectors. This method will account satisfactorily for the number of orbitals formed when applied to hybrids involving the s and p orbitals. (GS)

  14. Aerosol Intercomparison Scenarios for the Giovanni Multi-sensor Data Synergy “Advisor”

    NASA Astrophysics Data System (ADS)

    Lloyd, S. A.; Leptoukh, G. G.; Prados, A. I.; Shen, S.; Pan, J.; Rui, H.; Lynnes, C.; Fox, P. A.; West, P.; Zednik, S.

    2009-12-01

    The combination of remotely sensed aerosols datasets can result in synergistic products that are more useful than the sum of the individual datasets. Multi-sensor composite datasets can be constructed by data merging (taking very closely related parameters to create a single merged dataset to increase spatial and/or temporal coverage), cross-calibration (creating long-term climate data records from two very similar parameters), validation (using a parameter from one dataset to validate a closely related parameter in another), cross-comparison (comparing two datasets with different parameters), and data fusion (using two or more parameters to estimate a third parameter). However, care must be taken to note the differences in data provenance and quality when combining heterogeneous datasets. The NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) is currently in its first year of funding for our project Multi-sensor Data Synergy Advisor (MDSA or Giovanni Advisor) under the NASA Earth Science Technology Office (ESTO) Advanced Information Systems and Technology (AIST) program. The Giovanni Advisor will allow researchers to combine and compare aerosol data from multiple sensors using Giovanni, such that scientifically and statistically valid conclusions can be drawn. The Giovanni Advisor will assist the user in determining how to match up two (or more) sets of data that are related, yet significantly different in some way: in the exact phenomenon being measured, the measurement technique, or the location in space-time and/or the quality of the measurements. Failing to account for these differences in merging, validation, cross calibration, comparison or fusion is likely to yield scientifically dubious results. The Giovanni Advisor captures details of each parameter’s attributes, metadata, retrieval heritage, provenance and data quality and flags relevant differences so that the user can make appropriate “apples to apples” comparisons of

  15. Synergy in microcosms with environmentally realistic concentrations of prochloraz and esfenvalerate.

    PubMed

    Bjergager, Maj-Britt A; Hanson, Mark L; Lissemore, Linda; Henriquez, Nikki; Solomon, Keith R; Cedergreen, Nina

    2011-01-25

    pesticide treatments, indications of stabilisation or the beginning of recovery occurred between day 7 and day 14 and full recovery was observed in some of the less affected populations of cladocerans, copepods, and chironomids after 28 days. The occurrence of the synergistic interactions between prochloraz and esfenvalerate in the microcosms and at environmentally realistic concentrations implies that the synergistic interactions may also take place in invertebrate communities in natural ponds and ditches being exposed to azoles and pyrethroids via for example runoff or drift. The question of how to deal with synergy between chemicals in the environment from a regulatory perspective is briefly discussed. PMID:21216352

  16. A Synergy Method to Improve Ensemble Weather Predictions and Differential SAR Interferograms

    NASA Astrophysics Data System (ADS)

    Ulmer, Franz-Georg; Adam, Nico

    2015-11-01

    A compensation of atmospheric effects is essential for mm-sensitivity in differential interferometric synthetic aperture radar (DInSAR) techniques. Numerical weather predictions are used to compensate these disturbances allowing a reduction in the number of required radar scenes. Practically, predictions are solutions of partial differential equations which never can be precise due to model or initialisation uncertainties. In order to deal with the chaotic nature of the solutions, ensembles of predictions are computed. From a stochastic point of view, the ensemble mean is the expected prediction, if all ensemble members are equally likely. This corresponds to the typical assumption that all ensemble members are physically correct solutions of the set of partial differential equations. DInSAR allows adding to this knowledge. Observations of refractivity can now be utilised to check the likelihood of a solution and to weight the respective ensemble member to estimate a better expected prediction. The objective of the paper is to show the synergy between ensemble weather predictions and differential interferometric atmospheric correction. We demonstrate a new method first to compensate better for the atmospheric effect in DInSAR and second to estimate an improved numerical weather prediction (NWP) ensemble mean. Practically, a least squares fit of predicted atmospheric effects with respect to a differential interferogram is computed. The coefficients of this fit are interpreted as likelihoods and used as weights for the weighted ensemble mean. Finally, the derived weighted prediction has minimal expected quadratic errors which is a better solution compared to the straightforward best-fitting ensemble member. Furthermore, we propose an extension of the algorithm which avoids the systematic bias caused by deformations. It makes this technique suitable for time series analysis, e.g. persistent scatterer interferometry (PSI). We validate the algorithm using the well known

  17. Toward biophysical synergy: Investigating advection along the Polar Front to identify factors influencing Alaska sablefish recruitment

    NASA Astrophysics Data System (ADS)

    Shotwell, S. Kalei; Hanselman, Dana H.; Belkin, Igor M.

    2014-09-01

    index in the sablefish model provided moderate reduction in unexplained recruitment variability and increased future projections of spawning biomass in the medium term. Based on this result, we developed a conceptual model of three mechanisms that in combination form an ocean domain dynamic synergy (ODDS) which influences sablefish survival through the pelagic early life history stage. Successfully incorporating environmental time series into the sablefish assessment could establish a foundation for future ecosystem-based management and allow for more informed and efficient resource allocation to stakeholders.

  18. RF propagation measurement and model validation during RF/IR synergy trial VAMPIRA

    NASA Astrophysics Data System (ADS)

    Heemskerk, Eric

    2005-10-01

    The member nations of AC/323 SET-RTG056/RTG32 on Integration of Radar and Infrared for Ship Self Defence have performed the Validation Measurements for Propagation in the Infrared and Radar (VAMPIRA). The objective was to get insight into the radar and infrared synergy concentrated on propagation in a coastal environment including horizontal inhomogeneity and to validate radar and infrared propagation models. The trial was held in the period 25 March-5 April 2004 near Surendorf Germany. As part of the trial TNO made RF 1-way transmission measurements, 24 hours/day during the whole trial period. The transmission path over the Eckernforder Bucht in Northern Germany had a length of 8.2 km. The transmitted signal was a sweep consisting of 6 frequencies i.e. 3.36, 5.32, 8.015, 9.7, 13.45, and 15.71 GHz. The transmitter height was 11.5 m, the receiver height 6.4 m above 'normal null'. At each end of the path a meteorological station was installed measuring every 30s the air temperature, relative humidity, air pressure, wind speed and wind direction. About halfway the path the TNO meteo buoy was anchored measuring air temperature and relative humidity at 5 heights between 0.65 and 5.15m above the sea surface. Also the sea water temperature was measured by the buoy on a depth of 1m below the sea surface. The effects of evaporation ducting at the propagation at the various frequencies were clearly demonstrated. Some times very deep fadings were present at 13.45 and 15.71 GHz where at the same time almost no effect at 3.36 and 5.32 GHz was observed. The measured propagation at 15.71 GHz was more enhanced than at 13.45 GHz due to the ducting conditions and the elevation angle of the transmitter and receiver antenna. In several sample cases the 1-way propagation factors are computed for every 5 minutes using the propagation model TERPEM (Signal Science) and the vertical refractivity profiles computed by the TNO model TARMOS. The 1-way computed propagation factors compared very

  19. Mars 2001 Lander Mission: Measurement Synergy Through Coordinated Operations Planning and Implementation

    NASA Astrophysics Data System (ADS)

    Arvidson, R.

    1999-01-01

    exposed at the site, together with quantitative information on material mineralogy, chemistry, and physical properties (rock textures; soil grain size and shape distributions; degree and nature of soil induration; soil magnetic properties). Observations from the APEX, MECA, and MIP Experiments, including use of the robotic arm robotic arm camera (RAC) and the Marie Curie rover, will be used to address these parameters in a synergistic way. Further, calibration targets on APEX will provide radiometric and mineralogical control surfaces, and magnet targets will allow observations of magnetic phases. Patch plates on MECA will be imaged to determine adhesive and abrasive properties of soils. Coordinated mission planning is crucial for optimizing the measurement synergy among the packages included on the lander. This planning has already begun through generation of multi-sol detailed operations activities.

  20. Hybrid polarization control

    NASA Astrophysics Data System (ADS)

    Gray, George R.; Ibragimov, Edem; Sluz, Joseph; Sova, Raymond

    2005-05-01

    We demonstrate a novel method of polarization control that combines rotatable waveplates (angle control) and variable retarders (retardance control). Such a "hybrid" polarization controller performs far better than conventional controllers, allowing nearly perfect arbitrary-to-arbitrary polarization transformations. We show theoretically that the two control parameters augment one another because they tend to result in orthogonal movements on the Poincaré sphere.

  1. Nuclear hybrid energy infrastructure

    SciTech Connect

    Agarwal, Vivek; Tawfik, Magdy S.

    2015-02-01

    The nuclear hybrid energy concept is becoming a reality for the US energy infrastructure where combinations of the various potential energy sources (nuclear, wind, solar, biomass, and so on) are integrated in a hybrid energy system. This paper focuses on challenges facing a hybrid system with a Small Modular Reactor at its core. The core of the paper will discuss efforts required to develop supervisory control center that collects data, supports decision-making, and serves as an information hub for supervisory control center. Such a center will also be a model for integrating future technologies and controls. In addition, advanced operations research, thermal cycle analysis, energy conversion analysis, control engineering, and human factors engineering will be part of the supervisory control center. Nuclear hybrid energy infrastructure would allow operators to optimize the cost of energy production by providing appropriate means of integrating different energy sources. The data needs to be stored, processed, analyzed, trended, and projected at right time to right operator to integrate different energy sources.

  2. Rethinking Resources and Hybridity

    ERIC Educational Resources Information Center

    Gonsalves, Allison J.; Seiler, Gale; Salter, Dana E.

    2011-01-01

    This review explores Alfred Schademan's "What does playing cards have to do with science? A resource-rich view of African American young men" by examining how he uses two key concepts--hybridity and resources--to propose an approach to science education that counters enduring deficit notions associated with this population. Our response to…

  3. Hybrid Imaging in Oncology.

    PubMed

    Fatima, Nosheen; Zaman, Maseeh uz; Gnanasegaran, Gopinath; Zaman, Unaiza; Shahid, Wajeeha; Zaman, Areeba; Tahseen, Rabia

    2015-01-01

    In oncology various imaging modalities play a crucial role in diagnosis, staging, restaging, treatment monitoring and follow up of various cancers. Stand-alone morphological imaging like computerized tomography (CT) and magnetic resonance imaging (MRI) provide a high magnitude of anatomical details about the tumor but are relatively dumb about tumor physiology. Stand-alone functional imaging like positron emission tomography (PET) and single photon emission tomography (SPECT) are rich in functional information but provide little insight into tumor morphology. Introduction of first hybrid modality PET/CT is the one of the most successful stories of current century which has revolutionized patient care in oncology due to its high diagnostic accuracy. Spurred on by this success, more hybrid imaging modalities like SPECT/CT and PET/MR were introduced. It is the time to explore the potential applications of the existing hybrid modalities, developing and implementing standardized imaging protocols and train users in nuclear medicine and radiology. In this review we discuss three existing hybrid modalities with emphasis on their technical aspects and clinical applications in oncology. PMID:26320423

  4. Improved hybrid rocket fuel

    NASA Technical Reports Server (NTRS)

    Dean, David L.

    1995-01-01

    McDonnell Douglas Aerospace, as part of its Independent R&D, has initiated development of a clean burning, high performance hybrid fuel for consideration as an alternative to the solid rocket thrust augmentation currently utilized by American space launch systems including Atlas, Delta, Pegasus, Space Shuttle, and Titan. It could also be used in single stage to orbit or as the only propulsion system in a new launch vehicle. Compared to solid propellants based on aluminum and ammonium perchlorate, this fuel is more environmentally benign in that it totally eliminates hydrogen chloride and aluminum oxide by products, producing only water, hydrogen, nitrogen, carbon oxides, and trace amounts of nitrogen oxides. Compared to other hybrid fuel formulations under development, this fuel is cheaper, denser, and faster burning. The specific impulse of this fuel is comparable to other hybrid fuels and is between that of solids and liquids. The fuel also requires less oxygen than similar hybrid fuels to produce maximum specific impulse, thus reducing oxygen delivery system requirements.

  5. HYBRID RECEPTOR MODELS

    EPA Science Inventory

    A hybrid receptor model is a specified mathematical procedure which uses not only the ambient species concentration measurements that form the input data for a pure receptor model, but in addition source emission rates or atmospheric dispersion or transformation information chara...

  6. Hybridized polymer matrix composites

    NASA Technical Reports Server (NTRS)

    House, E. E.; Hoggatt, J. T.; Symonds, W. A.

    1980-01-01

    The extent to which graphite fibers are released from resin matrix composites that are exposed to fire and impact conditions was determined. Laboratory simulations of those conditions that could exist in the event of an aircraft crash and burn situation were evaluated. The effectiveness of various hybridizing concepts in preventing this release of graphite fibers were also evaluated. The baseline (i.e., unhybridized) laminates examined were prepared from commercially available graphite/epoxy, graphite/polyimide, and graphite/phenolic materials. Hybridizing concepts investigated included resin fillers, laminate coatings, resin blending, and mechanical interlocking of the graphite reinforcement. The baseline and hybridized laminates' mechanical properties, before and after isothermal and humidity aging, were also compared. It was found that a small amount of graphite fiber was released from the graphite/epoxy laminates during the burn and impact conditions used in this program. However, the extent to which the fibers were released is not considered a severe enough problem to preclude the use of graphite reinforced composites in civil aircraft structure. It also was found that several hybrid concepts eliminated this fiber release. Isothermal and humidity aging did not appear to alter the fiber release tendencies.

  7. Hybrid Anisotropic Micromesh

    NASA Astrophysics Data System (ADS)

    Gutzov, S.; Danchova, N.; Tsekov, R.; Barreno, I.; Ruiz del Portal, X.; Ulbikas, J.

    2015-10-01

    A new hybrid woven micromesh containing metal and polyester wires with a 2D porosity of about 30% has been created. The anisotropic microcomposite is developed as a new material with wide applications in thermal and electrical engineering. The mesh material is carefully characterized using electron microscopy, fluorescence microscopy, chemical analysis, thermal conductivity measurements and differential scanning calorimetry.

  8. Electric and hybrid vehicles

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Report characterizes state-of-the-art electric and hybrid (combined electric and heat engine) vehicles. Performance data for representative number of these vehicles were obtained from track and dynamometer tests. User experience information was obtained from fleet operators and individual owners of electric vehicles. Data on performance and physical characteristics of large number of vehicles were obtained from manufacturers and available literature.

  9. Hybridization of biomedical circuitry

    NASA Technical Reports Server (NTRS)

    Rinard, G. A.

    1978-01-01

    The design and fabrication of low power hybrid circuits to perform vital signs monitoring are reported. The circuits consist of: (1) clock; (2) ECG amplifier and cardiotachometer signal conditioner; (3) impedance pneumobraph and respiration rate processor; (4) hear/breath rate processor; (5) temperature monitor; and (6) LCD display.

  10. Hybrid Solar GHP Simulator

    Energy Science and Technology Software Center (ESTSC)

    2012-12-11

    This project provides an easy-to-use, menu-driven, software tool for designing hybrid solar-geothermal heat pump systems (GHP) for both heating- and cooling-dominated buildings. No such design tool currently exists. In heating-dominated buildings, the design approach takes advantage of glazed solar collectors to effectively balance the annual thermal loads on the ground with renewable solar energy. In cooling-dominated climates, the design approach takes advantage of relatively low-cost, unglazed solar collectors as the heat rejecting component. The primarymore » benefit of hybrid GHPs is the reduced initial cost of the ground heat exchanger (GHX). Furthermore, solar thermal collectors can be used to balance the ground loads over the annual cycle, thus making the GHX fully sustainable; in heating-dominated buildings, the hybrid energy source (i.e., solar) is renewable, in contrast to a typical fossil fuel boiler or electric resistance as the hybrid component; in cooling-dominated buildings, use of unglazed solar collectors as a heat rejecter allows for passive heat rejection, in contrast to a cooling tower that consumes a significant amount of energy to operate, and hybrid GHPs can expand the market by allowing reduced GHX footprint in both heating- and cooling-dominated climates. The design tool allows for the straight-forward design of innovative GHP systems that currently pose a significant design challenge. The project lays the foundations for proper and reliable design of hybrid GHP systems, overcoming a series of difficult and cumbersome steps without the use of a system simulation approach, and without an automated optimization scheme. As new technologies and design concepts emerge, sophisticated design tools and methodologies must accompany them and be made usable for practitioners. Lack of reliable design tools results in reluctance of practitioners to implement more complex systems. A menu-driven software tool for the design of hybrid solar GHP systems

  11. Hybridization and introgression in two ecologically dissimilar Fundulus hybrid zones.

    PubMed

    Schaefer, Jacob; Duvernell, David; Campbell, Dave Cooper

    2016-05-01

    Hybridization and introgression appear more common in rapidly evolving groups, suggesting an important role in the evolutionary process. Detailed studies of how extrinsic or intrinsic forces regulate hybridization and introgression have the potential for broadening our understanding of mechanisms generating diversity. Species in the Fundulus notatus species complex have broad overlapping ranges and occur in replicated hybrid zones along predictable stream gradients. Typical hybrid zone structure has Fundulus olivaceus in headwaters, F. notatus downstream, and hybrid zones near confluences or abrupt shifts in habitat. Rarely, the typical upstream-downstream orientation is reversed raising questions as to how hybrid zones are formed and maintained. We used next-generation sequencing data to study hybridization and introgression in hybrid zones in neighboring drainages that differ in orientation (typical and reversed). We predicted extrinsic forces linked to stream gradients would result in noticeable differences between the two. Contrary to predictions, the data indicate the hybrid zones are remarkably similar. We used individual-based simulations to explore the potential role of intrinsic and extrinsic forces in generating and maintaining typical and reversed hybrid zones. Simulation results were consistent with reversed hybrid zones being formed from stochastic processes combined with strong intrinsic forces and weak extrinsic forces. PMID:27062071

  12. Copper Phthalocyanine-Functionalized Graphitic Carbon Nitride: A Hybrid Heterostructure toward Photoelectrochemical and Photocatalytic Degradation Applications.

    PubMed

    Liu, Zhong-Guo; Wan, Jia-Yun; Yang, Ze; Wang, Shi-Quan; Wang, Hang-Xing

    2016-07-01

    In this work, alcian blue 8GX (AB), a copper(II) phthalocyanine derivative, was employed to functionalize graphitic carbon nitride (g-C3 N4 ) for the preparation of a highly efficient photocatalyst. The approach relies on a facile AB-assisted ethanol/water mixed-solvent exfoliation of bulk g-C3 N4 . The as-prepared g-C3 N4 /AB hybrid possesses significantly enhanced solution dispersibility and photoelectrochemical performance resulting from the synergistic effect between g-C3 N4 and AB, which involves the optimization of intimate interfacial contact, extension of light absorption range, and enhancement of charge-transfer efficiency. This synergy contributes enormously to the photocatalytic degradation of rhodamine 6G (R6G) under light irradiation. PMID:27305072

  13. Hybrid Ultra-Microporous Materials for Selective Xenon Adsorption and Separation.

    PubMed

    Mohamed, Mona H; Elsaidi, Sameh K; Pham, Tony; Forrest, Katherine A; Schaef, Herbert T; Hogan, Adam; Wojtas, Lukasz; Xu, Wenqian; Space, Brian; Zaworotko, Michael J; Thallapally, Praveen K

    2016-07-11

    The demand for Xe/Kr separation continues to grow due to the industrial significance of high-purity Xe gas. Current separation processes rely on energy intensive cryogenic distillation. Therefore, less energy intensive alternatives, such as physisorptive separation, using porous materials, are required. Herein we show that an underexplored class of porous materials called hybrid ultra-microporous materials (HUMs) affords new benchmark selectivity for Xe separation from Xe/Kr mixtures. The isostructural materials, CROFOUR-1-Ni and CROFOUR-2-Ni, are coordination networks that have coordinatively saturated metal centers and two distinct types of micropores, one of which is lined by CrO4 (2-) (CROFOUR) anions and the other is decorated by the functionalized organic linker. These nets offer unprecedented selectivity towards Xe. Modelling indicates that the selectivity of these nets is tailored by synergy between the pore size and the strong electrostatics afforded by the CrO4 (2-) anions. PMID:27238977

  14. Flexibility and pragmatism in promoting health: an experience of synergy between health and religion in the Islamic Republic of Iran.

    PubMed

    Adams, C; Manenti, A

    2012-08-01

    In the Islamic Republic of Iran, religion has traditionally played a central role in the lives of the people. Following the Islamic Revolution in 1979, it has also become integral to the country's governance. Since the Revolution, an exceptional synergy has arisen between the domain of religion and the health sector in the development of family planning policies, which have resulted in dramatic changes in population growth and fertility: the population growth rate decreased from 3.9% (1986) to 1.2% (2000) and total fertility from 6.8 (1984) to 2.1 (2000). The extraordinary aspect of this experience is that the position of religious authorities changed from one of opposition to one of active promotion of family planning. This paper describes the establishment and course of family planning programmes in Iran and makes use of interviews with two main protagonists of this experience (Dr Alireza Marandi--Minister of Health 1984-1989, 1993-1997; Dr Hossein Malekafzali--former Deputy Minister of Health). It is hoped that dissemination of this experience outside of the Islamic Republic of Iran will encourage the development of similar dialogue and synergy between religion and health in other countries. PMID:23057381

  15. Synergies Between The Next Generation Of Optical/ir Sky Survey Projects And The Square Kilometer Array

    NASA Astrophysics Data System (ADS)

    Chambers, Kenneth C.

    2007-12-01

    There are significant scientific synergies between proposed facilities making up the Square Kilometer Array and its precursor pathfinders, including the EVLA, the Allen Telescope, and LOFAR, and upcoming Optical/NIR Synoptic Survey Telescopes such as the Pan-STARRS Telescopes (PS1, PS4, PSn), and the LSST Corporation Telescope. Commissioning data from the PS1 System will be presented along with discussion of lessons learned to date from commissioning and issues arising from the start of the PS1 Science Mission this spring. The approach of the PS1 Science Consortium towards survey strategies and the synergies that arise from designing observational data sets to meet diverse science goals and the challenges of data reduction and coordinated scientific analysis tools in the epoch of multiple petabyte datasets will be presented. In particular we will focus on the scientific benefits of coordinating Optical/IR synoptic sky surveys such as Pan-STARRS and LSST with the SKA pathfinders and the proposed mid-frequency Radio Synoptic Survey Telescope as a component of the Square Kilometer Array. These include substantial gains for fundamental science across diverse physical and astrophysical fields of study and including both static sky and time domain multi-wavelength programs.

  16. Confirmation of Maslow’s Hypothesis of Synergy: Developing an Acceptance of Selfishness at the Workplace Scale

    PubMed Central

    Takaki, Jiro; Taniguchi, Toshiyo; Fujii, Yasuhito

    2016-01-01

    This study aimed to develop a new Acceptance of Selfishness at the Workplace Scale (ASWS) and to confirm Maslow’s hypothesis of synergy: if both a sense of contribution and acceptance of selfishness at the workplace are high, workers are psychologically healthy. In a cross-sectional study with employees of three Japanese companies, 656 workers answered a self-administered questionnaire on paper completely (response rate = 66.8%). Each questionnaire was submitted to us in a sealed envelope and analyzed. The ASWS indicated high internal consistency (Cronbach’s alpha = 0.86). Significant (p < 0.001) positive moderate correlations between ASWS scores and job control scores support the ASWS’s convergent and discriminant validity. Significant (p < 0.001) associations of ASWS scores with psychological distress and work engagement supported the ASWS’s criterion validity. In short, ASWS was a psychometrically satisfactory measure. Significant (p < 0.05) interactions between a sense of contribution and acceptance of selfishness at the workplace in linear regression models showed that when those two factors are low, psychological distress becomes high. However, when a sense of contribution and acceptance of selfishness are high, work engagement also becomes high. Thus, Maslow’s hypothesis of synergy was confirmed. PMID:27144575

  17. Improve Synergy Between Health Information Exchange and Electronic Health Records to Increase Rates of Continuously Insured Patients

    PubMed Central

    Gold, Rachel; Burdick, Tim; Angier, Heather; Wallace, Lorraine; Nelson, Christine; Likumahuwa-Ackman, Sonja; Sumic, Aleksandra; DeVoe, Jennifer E.

    2015-01-01

    Introduction: The Affordable Care Act increases health insurance options, yet many Americans may struggle to consistently maintain coverage. While health care providers have traditionally not been involved in providing insurance enrollment support to their patients, the ability for them to do so now exists. We propose that providers could capitalize on the expansion of electronic health records (EHRs) and the advances in health information exchanges (HIEs) to improve their patients’ insurance coverage rates and continuity. Evidence for Argument: We describe a project in which we are building strategies for linking, and thus improving synergy between, payer and EHR data. Through this effort, care teams will have access to new automated tools and increased EHR functionality designed to help them assist their patients in obtaining and maintaining health insurance coverage. Suggestion for the Future: The convergence of increasing EHR adoption, improving HIE functionality, and expanding insurance coverage options, creates new opportunities for clinics to help their patients obtain public health insurance. Harnessing this nascent ability to exchange information between payers and providers may improve synergies between HIE and EHRs, and thus support clinic-based efforts to keep patients continuously insured. PMID:26355818

  18. CFD study on local fluid-to-wall heat transfer in packed beds and field synergy analysis

    NASA Astrophysics Data System (ADS)

    Peng, Wenping; Xu, Min; Huai, Xiulan; Liu, Zhigang

    2016-04-01

    To reach the target of smaller pressure drop and better heat transfer performance, packed beds with small tube-to-particle diameter ratio ( D/d p<10) have now been considered in many areas. Fluid-to-wall heat transfer coefficient is an important factor determining the performance of this type of beds. In this work, local fluid- to-wall heat transfer characteristic in packed beds was studied by Computational Fluid Dynamics (CFD) at different Reynolds number for D/d p=1.5, 3.0 and 5.6. The results show that the fluid-to-wall heat transfer coefficient is oscillating along the bed with small tube-to-particle diameter ratio. Moreover, this phenomenon was explained by field synergy principle in detail. Two arrangement structures of particles in packed beds were recommended based on the synergy characteristic between flow and temperature fields. This study provides a new local understanding of fluid-to-wall heat transfer in packed beds with small tube-to-particle diameter ratio.

  19. Hybrid Interventions in Limb Salvage

    PubMed Central

    Huynh, Tam T.T.; Bechara, Carlos F.

    2013-01-01

    Hybrid interventions have become an integral part of our strategy for limb salvage in patients with multilevel arterial occlusive disease. In this article, we describe the commonly used hybrid interventions and review their indications and outcomes. Iliac stenting and femoral endarterectomy are the two most frequently performed procedures in hybrid cases. Short- and long-term outcomes of hybrid interventions are at least comparable to conventional endovascular and surgical revascularization procedures. Hybrid revascularization offers the efficiency and convenience of a single-stage revascularization. PMID:23805341

  20. The International Union for Health Promotion and Education (IUHPE) Student and Early Career Network (ISECN): a case illustrating three strategies for maximizing synergy in professional collaboration.

    PubMed

    Corbin, J Hope; Fisher, Emily A; Bull, Torill

    2012-09-01

    The International Union for Health Promotion and Education (IUHPE) Student and Early Career Network (ISECN) was constructed upon a foundation of research, using the Bergen Model of Collaborative Functioning (BMCF) as a blueprint to inform its leadership, communication, structure, and culture. The BMCF consists of inputs (partners, mission, and financial resources), throughputs (operational processes), and outputs (synergy and antagony). In this commentary, we use the BMCF to describe the ISECN work, highlighting opportunities, successes, and challenges. We also put forward three strategies derived from the BMCF that have been purposefully employed by ISECN to maximize its production of synergy from the voluntary contributions of its members. PMID:24802784