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Sample records for medium frequency reciprocating

  1. Breaking Lorentz Reciprocity with Frequency Conversion and Delay

    Science.gov (United States)

    Rosenthal, Eric I.; Chapman, Benjamin J.; Higginbotham, Andrew P.; Kerckhoff, Joseph; Lehnert, K. W.

    2017-10-01

    We introduce a method for breaking Lorentz reciprocity based upon the noncommutation of frequency conversion and delay. The method requires no magnetic materials or resonant physics, allowing for the design of scalable and broadband nonreciprocal circuits. With this approach, two types of gyrators—universal building blocks for linear, nonreciprocal circuits—are constructed. Using one of these gyrators, we create a circulator with >15 dB of isolation across the 5-9 GHz band. Our designs may be readily extended to any platform with suitable frequency conversion elements, including semiconducting devices for telecommunication or an on-chip superconducting implementation for quantum information processing.

  2. Generation of medium frequency electrotherapeutic signals

    Science.gov (United States)

    Płaza, Mirosław; Szcześniak, Zbigniew; Dudek, Jolanta

    2017-08-01

    In this paper, generation methods of sinusoidal medium frequency electrotherapeutic signals have been studied. Signals of this type are increasingly used in electrotherapy owing to the development of both physical medicine and engineering sciences. The article presents analysis and comparison of analogue and digital methods of generation therapeutic signals. Analysis presented in the paper attempts to answer the question which technique of medium frequency signal generation can be most broadly applied in electrotherapy methods.

  3. Theoretical evaluation of the efficiency of gas single-stage reciprocating compressor medium pressure units

    Science.gov (United States)

    Busarov, S. S.; Vasil'ev, V. K.; Busarov, I. S.; Titov, D. S.; Panin, Ju. N.

    2017-08-01

    Developed earlier and tested in such working fluid as air, the technology of calculating the operating processes of slow-speed long-stroke reciprocating stages let the authors to obtain successful results concerning compression of gases to medium pressures in one stage. In this connection, the question of the efficiency of the application of slow-speed long-stroke stages in various fields of technology and the national economy, where the working fluid is other gas or gas mixture, is topical. The article presents the results of the efficiency evaluation of single-stage compressor units on the basis of such stages for cases when ammonia, hydrogen, helium or propane-butane mixture is used as the working fluid.

  4. In situ stylus profilometer for a high frequency reciprocating tribometer

    Science.gov (United States)

    Kamps, T. J.; Walker, J. C.; Plint, A. G.

    2017-09-01

    Measuring the friction and wear characteristics of a tribological contact is essential to gaining a detailed understanding of its performance and predicted life. Wear rate and friction coefficient measurements are obtained from instrumented benchtop tribometers designed to replicate specific tribological contacts. Due to the difficulty of measuring wear in situ, measurements are typically made before and after an experiment. The wear rate must be assumed to be linear for it to be used to predict product life, however this is assumption can hide changes occurring during an experiment which indicate wear transitions. This paper details the design and validation of an in situ stylus profilometer for a reciprocating sliding tribometer to provide an insight into the wear transitions occurring during dry sliding of 52100 bearing steel against graphitic flake cast iron. The profilometer’s performance was validated using ground roughness standards and the accuracy found to be approximately 110 nm. Incubation, run-in and steady state wear regimes were identified by the profilometer and corroborated with friction coefficient data, providing an enhanced understanding of the tribological contact behaviour.

  5. A Pilot Study of Reciprocal Peer Tutoring in Irish Medium Schools

    OpenAIRE

    Thurston, Allen; Keenan, Ciara

    2014-01-01

    A pilot study to investigate the effects of mathematics peer tutoring in Irish medium primary schools was undertaken. Five schools and 90 students took part in the pilot. Materials and resources that had previously been shown to work in English medium Scottish schools were translated into Irish by CCEA. Irish medium teachers attended three professional development days. Teachers implemented the peer tutoring techniques during mathematics lessons during a period of 16 weeks. Changes in attainm...

  6. The frequency characteristics of medium voltage distribution system impedances

    Directory of Open Access Journals (Sweden)

    Liviu Emil Petrean

    2009-10-01

    Full Text Available In this paper we present the frequency characteristics of impedances involved in the electrical equivalent circuit of a large medium voltage distribution system. These impedances influence harmonics distortions propagation occurring due to the nonsinusoidal loads. We analyse the case of a 10 kV large urban distribution system which supplies industrial, commercial and residential customers. The influence of various parameters of the distribution network on the frequency characteristics are presented, in order to assess the interaction of harmonic distortion and distribution system network.

  7. Non-reciprocal Oersted field contribution to the current-induced frequency shift of magnetostatic surface waves

    OpenAIRE

    Haidar, Mohammad; Bailleul, Matthieu; Kostylev, Mikhail; Lao, Yuyan

    2013-01-01

    The influence of an electrical current on the propagation of magnetostatic surface waves is investigated in a relatively thick (40 nm) permalloy film both experimentally and theoretically. Contrary to previously studied thinner films where the dominating effect is the current-induced spin-wave Doppler shift, the magnetic field generated by the current (Oersted field) is found to induce a strong non-reciprocal frequency shift which overcompensates the Doppler shift. The measured current induce...

  8. Assessment of Lubricity Properties of Dimethyl Ether Using the Medium Frequency Reciprocating Rig

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Sorenson, Spencer C

    2001-01-01

    Adequate lubricity of a fuel is an important issue when the wear in diesel engine injection equipment is to be minimised. For conventional diesel oils, there exist methods capable of measuring the lubricity of the fuels. These methods cannot handle Dimethyl Ether (DME), as it has to be pressurised...... exceptionally low. By mixing the DME with very small quantities of additives the lubricity can be redressed. Only one additive was capable of giving DME a lubricity higher than the one of diesel oil. Even at such high lubricities it cannot be concluded that wear in the diesel injection pumps....... The calibration was achieved by using both the standard method for diesel oil and the MFPRR, to test three liquid fuels of varying lubricities. The result was that the MFPRR discriminated just as well between the fuel lubricities as did the standard method. The lubricity of DME was measured and was found...

  9. Electromagnetic Reciprocity.

    Energy Technology Data Exchange (ETDEWEB)

    Aldridge, David F.

    2014-11-01

    A reciprocity theorem is an explicit mathematical relationship between two different wavefields that can exist within the same space - time configuration. Reciprocity theorems provi de the theoretical underpinning for mod ern full waveform inversion solutions, and also suggest practical strategies for speed ing up large - scale numerical modeling of geophysical datasets . In the present work, several previously - developed electromagnetic r eciprocity theorems are generalized to accommodate a broader range of medi um, source , and receiver types. Reciprocity relations enabling the interchange of various types of point sources and point receivers within a three - dimensional electromagnetic model are derived. Two numerical modeling algorithms in current use are successfully tested for adherence to reciprocity. Finally, the reciprocity theorem forms the point of departure for a lengthy derivation of electromagnetic Frechet derivatives. These mathe matical objects quantify the sensitivity of geophysical electromagnetic data to variatio ns in medium parameters, and thus constitute indispensable tools for solution of the full waveform inverse problem. ACKNOWLEDGEMENTS Sandia National Labor atories is a multi - program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE - AC04 - 94AL85000. Signif icant portions of the work reported herein were conducted under a Cooperative Research and Development Agreement (CRADA) between Sandia National Laboratories (SNL) and CARBO Ceramics Incorporated. The author acknowledges Mr. Chad Cannan and Mr. Terry Pa lisch of CARBO Ceramics, and Ms. Amy Halloran, manager of SNL's Geophysics and Atmospheric Sciences Department, for their interest in and encouragement of this work. Special thanks are due to Dr . Lewis C. Bartel ( recently retired from Sandia National Labo ratories

  10. Family Meal Frequency and Alcohol and Tobacco Use in Adolescence: Testing Reciprocal Effects

    Science.gov (United States)

    White, James; Halliwell, Emma

    2011-01-01

    This longitudinal study tested the direction of associations between family meals and alcohol and tobacco consumption during early adolescence. We examined family meal frequency, family connectedness, alcohol (binge drinking, drunkenness), and tobacco consumption (past year, daily frequency) in 671 adolescents (51% women; mean age, Wave 1 = 14.05…

  11. Frequency selective bistable switching in metamaterial based photonic bandgap medium

    Science.gov (United States)

    Jose, Jolly

    2014-10-01

    We present frequency selective bistable response at the defect mode of the zero-nbar bandgap of a photonic bandgap (PBG) material made of negative and positive index media. The nonlinear (Kerr) layer acts as the defect layer in the periodic PBG material. Incorporating metamaterial based electromagnetically induced transparency (EIT) like resonance in the positive layer leads to unprecedented line narrowing of the defect mode which in turn facilitates narrow frequency selective bistable operation, wherein all the bistable characteristics can be effectively engineered. Thresholding the output intensity selects the narrow band of frequencies that exhibit bistability.

  12. Muscle force production with low and medium frequency burst modulated biphasic pulsed currents.

    Science.gov (United States)

    Bellew, James W; Sanders, Kyle; Schuman, Kristen; Barton, Matt

    2014-02-01

    Russian current, a medium frequency burst modulated alternating current (BMAC), is widely used for NMES, but has not been shown to elicit forces near voluntary maximum. In contrast, low frequency BMAC has been shown to produce greater force production than Russian and most recently, medium frequency burst modulated biphasic pulsed current (BMBPC) elicited greater force than Russian. Whether low frequency BMBPC yields greater force than medium frequency BMBPC is unknown. This study examined elicited forces using BMBPC with low and medium frequency carrier currents. A cross-over design where percent maximal isometric knee extensor forces (%MVIF) elicited using BMBPC with low or medium kilohertz carrier frequencies were compared in 23 subjects. Perceived discomfort was also assessed. Data were compared using paired samples t-tests. 98.4% of the MVIF was elicited with the low frequency BMBPC which was significantly greater (p current. Cohen's d effect size of 2.146 indicated a "huge effect". Perceived discomfort of the low frequency current was 5.7/10 and was significantly greater (p current (3.6/10). BMBPC with low frequency carrier current elicits forces approximating maximal volitional force. These findings offer new evidence with strong clinical implications when using NMES.

  13. Application of Low Frequency and Medium Frequency Currents in the Management of Acute and Chronic Pain-A Narrative Review

    OpenAIRE

    Samuel, Stephen Rajan; Maiya, G Arun

    2015-01-01

    Trancutaneous electrical nerve stimulation (TENS) and interferential therapy (IFT) have been a regular line of treatment for various types of acute and chronic pain. This review aims to compile the latest literature in pain management using these modalities which use low-frequency and medium-frequency currents. The Cochrane Library, Scopus, PubMed, MEDLINE, and CINAHL were searched and studies were examined from their inception till October 2013. After title and abstract screening the relevan...

  14. State of art survey for design of medium frequency high power transformer

    DEFF Research Database (Denmark)

    Vaisambhayana, Sriram; Dincan, Catalin; Shuyu, Cao

    2016-01-01

    Medium and high frequency, high power transformers play an important role in footprint reduction along with their functions of galvanic isolation, and voltage transformation in all high power converters typically used in traction power systems, offshore wind plant power converters, and solid state...... transformer based distribution system grids. This state of art report analysis the various materials and design tradeoffs that govern the electromagnetic behavior and loss mechanisms of the medium frequency transformer applications. Typical winding and core geometries that have been reported extensively...

  15. Populations of striatal medium spiny neurons encode vibrotactile frequency in rats: modulation by slow wave oscillations.

    Science.gov (United States)

    Hawking, Thomas G; Gerdjikov, Todor V

    2013-01-01

    Dorsolateral striatum (DLS) is implicated in tactile perception and receives strong projections from somatosensory cortex. However, the sensory representations encoded by striatal projection neurons are not well understood. Here we characterized the contribution of DLS to the encoding of vibrotactile information in rats by assessing striatal responses to precise frequency stimuli delivered to a single vibrissa. We applied stimuli in a frequency range (45-90 Hz) that evokes discriminable percepts and carries most of the power of vibrissa vibration elicited by a range of complex fine textures. Both medium spiny neurons and evoked potentials showed tactile responses that were modulated by slow wave oscillations. Furthermore, medium spiny neuron population responses represented stimulus frequency on par with previously reported behavioral benchmarks. Our results suggest that striatum encodes frequency information of vibrotactile stimuli which is dynamically modulated by ongoing brain state.

  16. Time-domain electromagnetic energy in a frequency-dispersive left-handed medium

    International Nuclear Information System (INIS)

    Cui Tiejun; Kong Jinau

    2004-01-01

    From Maxwell's equations and the Poynting theorem, the time-domain electric and magnetic energy densities are generally defined in the frequency-dispersive media based on the conservation of energy. As a consequence, a general definition of electric and magnetic energy is proposed. Comparing with existing formulations of electric and magnetic energy in frequency-dispersive media, the new definition is more reasonable and is valid in any case. Using the new definition and staring from the equation of motion, we have shown rigorously that the total energy density and the individual electric and magnetic energy densities are always positive in a realistic artificial left-handed medium (LHM) [R. A. Shelby, D. R. Smith, and S. Schultz, Science 292, 77 (2001)], which obeys actually the Lorentz medium model, although such a LHM has negative permittivity and negative permeability simultaneously in a certain frequency range. We have also shown that the conservation of energy is not violated in LHM. The earlier conclusions can be easily extended to the Drude medium model and the cold plasma medium model. Through an exact analysis of a one-dimensional transient current source radiating in LHM, numerical results are given to demonstrate that the work done by source, the power flowing outwards a surface, and the electric and magnetic energy stored in a volume are all positive in the time domain

  17. Effects of the interstellar medium on detection of low-frequency gravitational waves

    International Nuclear Information System (INIS)

    Stinebring, Dan

    2013-01-01

    Time variable delays due to radio wave propagation in the ionized interstellar medium are a substantial source of error in pulsar timing array efforts. We describe the physical origin of these effects, discussing dispersive and scattering effects separately. Where possible, we give estimates of the magnitude of timing errors produced by these effects and their scaling with radio frequency. Although there is general understanding of the interstellar medium propagation errors to be expected with pulsar timing array observations, detailed comparison between theory and practice is still in its infancy, particularly with regard to scattering effects. (paper)

  18. The Reciprocalizer

    DEFF Research Database (Denmark)

    Parigi, Dario; Kirkegaard, Poul Henning

    2013-01-01

    The geometry of reciprocal structures is extremely difficult to predict and control, and it cannot be described with the available CAD software or by hierarchical, associative parametric modellers. The geometry of a network of reciprocally connected elements is a characteristic that emerges, bott...

  19. Frequency-domain modelling of gain in pump-probe experiment by an inhomogeneous medium

    Science.gov (United States)

    Kim, Minkyung; Oh, Sang Soon; Hess, Ortwin; Rho, Junsuk

    2018-02-01

    Introduction of a gain medium in lossy plasmonic metamaterials reduces and compensates losses or even amplifies an incident light often with nonlinear optical effect. Here, optical gain in a pump-probe experimental setup is effectively calculated in the frequency-domain by approximating a gain material as an inhomogeneous medium. Spatially varying local field amplitudes of the pump and probe beams are included in the model to reproduce the inhomogeneous gain effect, in which population inversion occurs most strongly near the surface and decays along the propagation direction. We demonstrate that transmission spectra calculated by this method agree well with finite-difference time-domain simulation results. This simplified approach of gain modelling offers an easy and reliable way to analyze wave propagation in a gain medium without nonlinear time-domain calculation.

  20. Frequency stabilization of multiple lasers on a single medium-finesse cavity

    Science.gov (United States)

    Han, Chengyin; Zhou, Min; Gao, Qi; Li, Shangyan; Zhang, Shuang; Qiao, Hao; Ai, Di; Zhang, Mengya; Lou, Ge; Luo, Limeng; Xu, Xinye

    2018-04-01

    We present a simple, compact, and robust frequency stabilization system of three lasers operating at 649, 759, and 770 nm, respectively. These lasers are applied in experiments on ytterbium optical lattice clocks, for which each laser needs to have a linewidth of a few hundred or tens of kilohertz while maintaining a favorable long-term stability. Here, a single medium-finesse cavity is adopted as the frequency reference and the standard Pound-Drever-Hall technique is used to stabilize the laser frequencies. Based on the independent phase modulation, multiple-laser locking is demonstrated without mutual intervention. The locked lasers are measured to have a linewidth of 100 kHz and the residual frequency drift is about 78.5 Hz s-1. This kind of setup provides a construction that is much simpler than that in previous work.

  1. Low-frequency asymptotic analysis of seismic reflection from afluid-saturated medium

    Energy Technology Data Exchange (ETDEWEB)

    Silin, D.B.; Korneev, V.A.; Goloshubin, G.M.; Patzek, T.W.

    2004-04-14

    Reflection of a seismic wave from a plane interface betweentwo elastic media does not depend on the frequency. If one of the mediais poroelastic and fluid-saturated, then the reflection becomesfrequency-dependent. This paper presents a low-frequency asymptoticformula for the reflection of seismic plane p-wave from a fluid-saturatedporous medium. The obtained asymptotic scaling of the frequency-dependentcomponent of the reflection coefficient shows that it is asymptoticallyproportional to the square root of the product of the reservoir fluidmobility and the frequency of the signal. The dependence of this scalingon the dynamic Darcy's law relaxation time is investigated as well.Derivation of the main equations of the theory of poroelasticity from thedynamic filtration theory reveals that this relaxation time isproportional to Biot's tortuosity parameter.

  2. Application of low frequency and medium frequency currents in the management of acute and chronic pain-a narrative review.

    Science.gov (United States)

    Samuel, Stephen Rajan; Maiya, G Arun

    2015-01-01

    Trancutaneous electrical nerve stimulation (TENS) and interferential therapy (IFT) have been a regular line of treatment for various types of acute and chronic pain. This review aims to compile the latest literature in pain management using these modalities which use low-frequency and medium-frequency currents. The Cochrane Library, Scopus, PubMed, MEDLINE, and CINAHL were searched and studies were examined from their inception till October 2013. After title and abstract screening the relevant studies were included for this review. We found through this review that even though TENS and IFT are used in management of pain, there is limited amount of high quality research available in this area. Most of the studies lack methodological quality and have a low sample size.

  3. Application of low frequency and medium frequency currents in the management of acute and chronic pain-A narrative review

    Directory of Open Access Journals (Sweden)

    Stephen Rajan Samuel

    2015-01-01

    Full Text Available Trancutaneous electrical nerve stimulation (TENS and interferential therapy (IFT have been a regular line of treatment for various types of acute and chronic pain. This review aims to compile the latest literature in pain management using these modalities which use low-frequency and medium-frequency currents. The Cochrane Library, Scopus, PubMed, MEDLINE, and CINAHL were searched and studies were examined from their inception till October 2013. After title and abstract screening the relevant studies were included for this review. We found through this review that even though TENS and IFT are used in management of pain, there is limited amount of high quality research available in this area. Most of the studies lack methodological quality and have a low sample size.

  4. Application of Low Frequency and Medium Frequency Currents in the Management of Acute and Chronic Pain-A Narrative Review

    Science.gov (United States)

    Samuel, Stephen Rajan; Maiya, G Arun

    2015-01-01

    Trancutaneous electrical nerve stimulation (TENS) and interferential therapy (IFT) have been a regular line of treatment for various types of acute and chronic pain. This review aims to compile the latest literature in pain management using these modalities which use low-frequency and medium-frequency currents. The Cochrane Library, Scopus, PubMed, MEDLINE, and CINAHL were searched and studies were examined from their inception till October 2013. After title and abstract screening the relevant studies were included for this review. We found through this review that even though TENS and IFT are used in management of pain, there is limited amount of high quality research available in this area. Most of the studies lack methodological quality and have a low sample size. PMID:25709199

  5. Improving Ambiguity Resolution for Medium Baselines Using Combined GPS and BDS Dual/Triple-Frequency Observations.

    Science.gov (United States)

    Gao, Wang; Gao, Chengfa; Pan, Shuguo; Wang, Denghui; Deng, Jiadong

    2015-10-30

    The regional constellation of the BeiDou navigation satellite system (BDS) has been providing continuous positioning, navigation and timing services since 27 December 2012, covering China and the surrounding area. Real-time kinematic (RTK) positioning with combined BDS and GPS observations is feasible. Besides, all satellites of BDS can transmit triple-frequency signals. Using the advantages of multi-pseudorange and carrier observations from multi-systems and multi-frequencies is expected to be of much benefit for ambiguity resolution (AR). We propose an integrated AR strategy for medium baselines by using the combined GPS and BDS dual/triple-frequency observations. In the method, firstly the extra-wide-lane (EWL) ambiguities of triple-frequency system, i.e., BDS, are determined first. Then the dual-frequency WL ambiguities of BDS and GPS were resolved with the geometry-based model by using the BDS ambiguity-fixed EWL observations. After that, basic (i.e., L1/L2 or B1/B2) ambiguities of BDS and GPS are estimated together with the so-called ionosphere-constrained model, where the ambiguity-fixed WL observations are added to enhance the model strength. During both of the WL and basic AR, a partial ambiguity fixing (PAF) strategy is adopted to weaken the negative influence of new-rising or low-elevation satellites. Experiments were conducted and presented, in which the GPS/BDS dual/triple-frequency data were collected in Nanjing and Zhengzhou of China, with the baseline distance varying from about 28.6 to 51.9 km. The results indicate that, compared to the single triple-frequency BDS system, the combined system can significantly enhance the AR model strength, and thus improve AR performance for medium baselines with a 75.7% reduction of initialization time on average. Besides, more accurate and stable positioning results can also be derived by using the combined GPS/BDS system.

  6. Frequency pulling in a low-voltage medium-power gyrotron

    Science.gov (United States)

    Luo, Li; Du, Chao-Hai; Huang, Ming-Guang; Liu, Pu-Kun

    2018-04-01

    Many recent biomedical applications use medium-power frequency-tunable terahertz (THz) sources, such as sensitivity-enhanced nuclear magnetic resonance, THz imaging, and biomedical treatment. As a promising candidate, a low-voltage gyrotron can generate watt-level, continuous THz-wave radiation. In particular, the frequency-pulling effect in a gyrotron, namely, the effect of the electron beam parameters on the oscillation frequency, can be used to tune the operating frequency. Most previous investigations used complicated and time-consuming gyrotron nonlinear theory to study the influence of many beam parameters on the interaction performance. While gyrotron linear theory investigation demonstrates the advantages of rapidly and clearly revealing the physical influence of individual key beam parameters on the overall system performance, this paper demonstrates systematically the use of gyrotron linear theory to study the frequency-pulling effect in a low-voltage gyrotron with either a Gaussian or a sinusoidal axial-field profile. Furthermore, simulations of a gyrotron operating in the first axial mode are carried out in the framework of nonlinear theory as a contrast. Close agreement is achieved between the two theories. Besides, some interesting results are obtained. In a low-current sinusoidal-profile cavity, the ranges of frequency variation for different axial modes are isolated from each other, and the frequency tuning bandwidth for each axial mode increases by increasing either the beam voltage or pitch factor. Lowering the voltage, the total tuning ranges are squeezed and become concentrated. However, the isolated frequency regions of each axial mode cannot be linked up unless the beam current is increased, meaning that higher current operation is the key to achieving a wider and continuous tuning frequency range. The results presented in this paper can provide a reference for designing a broadband low-voltage gyrotron.

  7. Frequency of reciprocal translocations as a function of gamma-ray dose in acute spermatogonial irradiation of the rabbit

    International Nuclear Information System (INIS)

    Vyglenov, A.; Benova, D.; Baev, I.; Karadzhov, A.

    1981-01-01

    Adult rabbit males were given acute gamma-ray exposures at dose levels of 0.5, 1.0, 3.0, or 5.0 Gy. The reciprocal translocations arisen at the premeiotic cytogenetic techniques at a 5 month postradiation. The findings indicated that increasing the dose up to 3.0 Gy resulted in a rise of translocation yields, while 5.0 Gy doses produced an abrupt fall. For the dose range studied, dose-response data were best described by a linear-quadratic equation. Based on the evidence of peak translocation yields obtained with 3.0 Gy exposures, rabbit spermatogonia were characterized as being more sensitive to radiation cell killing, as compared to mouse spermatogonia, where maximum translocation yields are reportedly observed at 6 to 8 Gy doses. As opposed to this, genetic radiosensitivity of spermatogonia proved lower in the rabbit than in the mouse. (A.B.)

  8. Computational Vibroacoustics in Low- and Medium- Frequency Bands: Damping, ROM, and UQ Modeling

    Directory of Open Access Journals (Sweden)

    Roger Ohayon

    2017-06-01

    Full Text Available Within the framework of the state-of-the-art, this paper presents a summary of some common research works carried out by the authors concerning computational methods for the prediction of the responses in the frequency domain of general linear dissipative vibroacoustics (structural-acoustic systems for liquid and gas in the low-frequency (LF and medium-frequency (MF domains, including uncertainty quantification (UQ that plays an important role in the MF domain. The system under consideration consists of a deformable dissipative structure, coupled with an internal dissipative acoustic fluid including a wall acoustic impedance, and surrounded by an infinite acoustic fluid. The system is submitted to given internal and external acoustic sources and to prescribed mechanical forces. An efficient reduced-order computational model (ROM is constructed using a finite element discretization (FEM for the structure and the internal acoustic fluid. The external acoustic fluid is treated using a symmetric boundary element method (BEM in the frequency domain. All the required modeling aspects required for the analysis in the MF domain have been introduced, in particular the frequency-dependent damping phenomena and model uncertainties. An industrial application to a complex computational vibroacoustic model of an automobile is presented.

  9. Medium Band Least Squares Estimation of Fractional Cointegration in the Presence of Low-Frequency Contamination

    DEFF Research Database (Denmark)

    Christensen, Bent Jesper; Varneskov, Rasmus T.

    This paper introduces a new estimator of the fractional cointegrating vector between stationary long memory processes that is robust to low-frequency contamination such as level shifts, i.e., structural changes in the means of the series, and deterministic trends. In particular, the proposed medium...... the cointegration strength and testing MBLS against the existing narrow band least squares estimator are developed. Finally, the asymptotic framework for the MBLS estimator is used to provide new perspectives on volatility factors in an empirical application to long-span realized variance series for S&P 500...

  10. Improving Ambiguity Resolution for Medium Baselines Using Combined GPS and BDS Dual/Triple-Frequency Observations

    Directory of Open Access Journals (Sweden)

    Wang Gao

    2015-10-01

    Full Text Available The regional constellation of the BeiDou navigation satellite system (BDS has been providing continuous positioning, navigation and timing services since 27 December 2012, covering China and the surrounding area. Real-time kinematic (RTK positioning with combined BDS and GPS observations is feasible. Besides, all satellites of BDS can transmit triple-frequency signals. Using the advantages of multi-pseudorange and carrier observations from multi-systems and multi-frequencies is expected to be of much benefit for ambiguity resolution (AR. We propose an integrated AR strategy for medium baselines by using the combined GPS and BDS dual/triple-frequency observations. In the method, firstly the extra-wide-lane (EWL ambiguities of triple-frequency system, i.e., BDS, are determined first. Then the dual-frequency WL ambiguities of BDS and GPS were resolved with the geometry-based model by using the BDS ambiguity-fixed EWL observations. After that, basic (i.e., L1/L2 or B1/B2 ambiguities of BDS and GPS are estimated together with the so-called ionosphere-constrained model, where the ambiguity-fixed WL observations are added to enhance the model strength. During both of the WL and basic AR, a partial ambiguity fixing (PAF strategy is adopted to weaken the negative influence of new-rising or low-elevation satellites. Experiments were conducted and presented, in which the GPS/BDS dual/triple-frequency data were collected in Nanjing and Zhengzhou of China, with the baseline distance varying from about 28.6 to 51.9 km. The results indicate that, compared to the single triple-frequency BDS system, the combined system can significantly enhance the AR model strength, and thus improve AR performance for medium baselines with a 75.7% reduction of initialization time on average. Besides, more accurate and stable positioning results can also be derived by using the combined GPS/BDS system.

  11. Breathing as a low frequency wave propagation in nonlinear elastic permeable medium

    International Nuclear Information System (INIS)

    Kyriakou, Elizabeth; McKenzie, David R.; Suchowerska, Natalka; Fulton, Roger R.

    2007-01-01

    Breathing can be regarded as a type of low frequency wave propagation. Unlike sound propagation in open air, in breathing, the air compressibility is not as important as the flow of air, and to a first approximation the air can be regarded as incompressible. We have developed a one-dimensional analytical description of wave motion in a metamaterial consisting of a porous elastic medium contained within chambers, separated by plates with orifices representing the minor airways. The metamaterial is placed within a cylinder with impermeable sides representing the thorax, driven at one end by a piston representing the diaphragm. The incompressible air is able to escape from the top of the cylinder. The solutions to the wave equation have characteristics that depend on the values of permeability (defined by the size of the orifice in the plates), the Young's modulus of the elastic medium and the density of lung tissue. A 'normal' regime is identified in which the strain of the medium near the diaphragm is large and the strain at the top of the cylinder near the outlet is small. An 'abnormal' regime is also identified in which the opposite applies. A rapid transition between the two regimes can be caused by changing the parameters representing the lung tissue. This transition may represent the onset of a disease state such as asthma

  12. Electromagnetic Low-Frequency Dipolar Excitation of Two Metal Spheres in a Conductive Medium

    Directory of Open Access Journals (Sweden)

    Panayiotis Vafeas

    2012-01-01

    Full Text Available This work concerns the low-frequency interaction of a time-harmonic magnetic dipole, arbitrarily orientated in the three-dimensional space, with two perfectly conducting spheres embedded within a homogeneous conductive medium. In such physical applications, where two bodies are placed near one another, the 3D bispherical geometry fits perfectly. Considering two solid impenetrable (metallic obstacles, excited by a magnetic dipole, the scattering boundary value problem is attacked via rigorous low-frequency expansions in terms of integral powers (ikn, where n≥0, k being the complex wave number of the exterior medium, for the incident, scattered, and total non-axisymmetric electric and magnetic fields. We deal with the static (n=0 and the dynamic (n=1,2,3 terms of the fields, while for n≥4 the contribution has minor significance. The calculation of the exact solutions, satisfying Laplace’s and Poisson’s differential equations, leads to infinite linear systems, solved approximately within any order of accuracy through a cut-off procedure and via numerical implementation. Thus, we obtain the electromagnetic fields in an analytically compact fashion as infinite series expansions of bispherical eigenfunctions. A simulation is developed in order to investigate the effect of the radii ratio, the relative position of the spheres, and the position of the dipole on the real and imaginary parts of the calculated scattered magnetic field.

  13. Theoretical study of the infrared frequencies of crystalline methyl acetate under interstellar medium conditions.

    Science.gov (United States)

    Narayanan, Radhika; Inomata, Kensuke; Gopakumar, Geetha; Sivaraman, Bhalamurugan; Zempo, Yasunari; Hada, Masahiko

    2016-01-15

    Identification of methyl acetate in the interstellar medium (ISM) and its spectroscopic studies have prompted us to investigate the structure of crystalline methyl acetate using numerical calculations. Here, we present a theoretical study of the structure of crystalline methyl acetate and its isotopologues and compare the calculated infrared (IR) spectra with the available experimental data. The optimized structure and vibrational properties were calculated using SIESTA software at 0 K. In the optimization process, the Perdew-Burke-Ernzerhof functional and conjugate gradient methods were used with double zeta polarization basis functions. After optimization of the periodic structure, the vibrational frequencies and normal modes were calculated within the harmonic approximation. Using the calculated results, we refine the mode assignments of experimental work on crystalline methyl acetate and determine the low frequency modes (below 650 cm(-1)). To investigate the accuracy of the pseudopotential and confirm the IR frequencies, we performed molecular calculations using a periodic model of methyl acetate and its isotopologues using SIESTA and compared them with results obtained from Gaussian 09 (all electron method) calculations. Finally, we assigned the vibrational modes of crystalline CD3-COO-CH3 and CH3-COO-CD3, for which experimental data are not available in the crystalline phase under ISM conditions. For all of the calculation methods, the IR vibrational modes of molecular and crystalline methyl acetate and its isotopologues were in good agreement with the available experimental data and predict the unavailable values. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Multiple-Time-Scales Hierarchical Frequency Stability Control Strategy of Medium-Voltage Isolated Microgrid

    DEFF Research Database (Denmark)

    Zhao, Zhuoli; Yang, Ping; Guerrero, Josep M.

    2016-01-01

    In this paper, an islanded medium-voltage (MV) microgrid placed in Dongao Island is presented, which integrates renewable-energy-based distributed generations (DGs), energy storage system (ESS), and local loads. In an isolated microgrid without connection to the main grid to support the frequency....... In this way, dynamic stability control that cope with disturbances in short-time scale is implemented by microgrid central controller (MGCC) within Zone B and Zone C. Meanwhile, steady-state stability control to solve the peaks and valleys problem of loads and DGs in long-time scale is executed by microgrid...... energy management system (MEMS) within Zone A. Furthermore, based on the developed complete small-signal state-space model, sensitivity analysis of the eigenvalues is conducted in order to reveal the dynamic stability margin of the MV microgrid, and to identify the proper range of the control parameters...

  15. Evaluation of frequency-dependent ultrasound attenuation in transparent medium using focused shadowgraph technique

    Science.gov (United States)

    Iijima, Yukina; Kudo, Nobuki

    2017-07-01

    Acoustic fields of a short-pulsed ultrasound propagating through a transparent medium with ultrasound attenuation were visualized by the focused shadowgraph technique. A brightness waveform and its spatial integrations were derived from a visualized field image and compared with a pressure waveform measured by a membrane hydrophone. The experimental results showed that first-order integration of the brightness wave has good agreement with the pressure waveforms. Frequency-dependent attenuation of the pulse propagating through castor oil was derived from brightness and pressure waveforms, and attenuation coefficients determined from focused shadowgraphy and hydrophone techniques showed good agreement. The results suggest the usefulness of the shadowgraph technique not only for the visualization of ultrasound fields but also for noncontact estimation of rough pressure waveforms and correct ultrasound attenuation.

  16. Extending the frequency range of free-field reciprocity calibration of measurement microphones to frequencies up to 150 kHz

    DEFF Research Database (Denmark)

    Barrera Figueroa, Salvador; Torras Rosell, Antoni; Jacobsen, Finn

    2013-01-01

    Measurement microphones are typically calibrated in a free field at frequencies up to 50 kHz. This is a sufficiently high frequency for the most sound measurement applications related with noise assessment. However, other applications such as the measurement of noise emitted by ultrasound cleanin...

  17. Electric Field Simulations and Analysis for High Voltage High Power Medium Frequency Transformer

    Directory of Open Access Journals (Sweden)

    Pei Huang

    2017-03-01

    Full Text Available The electronic power transformer (EPT raises concerns for its notable size and volume reduction compared with traditional line frequency transformers. Medium frequency transformers (MFTs are important components in high voltage and high power energy conversion systems such as EPTs. High voltage and high power make the reliable insulation design of MFT more difficult. In this paper, the influence of wire type and interleaved winding structure on the electric field distribution of MFT is discussed in detail. The electric field distributions for six kinds of typical non-interleaved windings with different wire types are researched using a 2-D finite element method (FEM. The electric field distributions for one non-interleaved winding and two interleaved windings are also studied using 2-D FEM. Furthermore, the maximum electric field intensities are obtained and compared. The results show that, in this case study, compared with foil conductor, smaller maximum electric field intensity can be achieved using litz wire in secondary winding. Besides, interleaving can increase the maximum electric field intensity when insulation distance is constant. The proposed method of studying the electric field distribution and analysis results are expected to make a contribution to the improvement of electric field distribution in transformers.

  18. A comparison of the analgesic efficacy of medium-frequency alternating current and TENS.

    Science.gov (United States)

    Ward, Alex R; Lucas-Toumbourou, Stacey; McCarthy, Brigid

    2009-12-01

    To compare the analgesic efficacy of burst-modulated medium-frequency alternating current (BMAC) and transcutaneous electrical nerve stimulation (TENS) using an experimental cold pain model. Within-group crossover study. A university research laboratory. Twenty healthy subjects. BMAC (4-kHz AC applied in 4-millisecond bursts at 50Hz) and TENS (125-microsecond phase duration applied at a frequency of 50Hz) administered to each participant on separate occasions. Time to cold pain threshold. The mean time to cold pain threshold with the BMAC intervention was no different than with TENS. Statistical analysis showed that both interventions elevated the cold pain threshold significantly [BMAC: increase=15.2seconds, 97.5% confidence interval (CI) 3.1 to 27.2, P=0.01; TENS: increase=15.4seconds, 97.5%CI 2.5 to 28.4, P=0.02], and the difference between interventions was not simply insignificant but the intervention effects were 'significantly the same' (mean difference=0.3seconds, 95%CI -15.3 to 15.9, P=0.97). BMAC is as effective as TENS in increasing cold pain thresholds in healthy subjects. Since BMAC has been shown to be more comfortable than TENS in previous studies and is likely to be better accepted and tolerated by patients, clinical investigation is warranted.

  19. Propagation of frequency-chirped laser pulses in a medium of atoms with a Λ-level scheme

    International Nuclear Information System (INIS)

    Demeter, G.; Dzsotjan, D.; Djotyan, G. P.

    2007-01-01

    We study the propagation of frequency-chirped laser pulses in optically thick media. We consider a medium of atoms with a Λ level-scheme (Lambda atoms) and also, for comparison, a medium of two-level atoms. Frequency-chirped laser pulses that induce adiabatic population transfer between the atomic levels are considered. They induce transitions between the two lower (metastable) levels of the Λ-atoms and between the ground and excited states of the two-level atoms. We show that associated with this adiabatic population transfer in Λ-atoms, there is a regime of enhanced transparency of the medium--the pulses are distorted much less than in the medium of two-level atoms and retain their ability to transfer the atomic population much longer during propagation

  20. Extending the frequency range of free-field reciprocity calibration of measurement microphones to frequencies up to 150 kHz

    DEFF Research Database (Denmark)

    Barrera Figueroa, Salvador; Torras Rosell, Antoni; Jacobsen, Finn

    2013-01-01

    machines and failure detection in aeronautic structures require that the sensitivity of the microphone is known at frequencies up to 150 kHz. Another area of particular interest is the investigation of the perception mechanisms of ultrasound. In any of these applications, it is of fundamental importance...... to establish a well-defined traceability chain to support the measurement results. In order to extend the frequency range of free-field calibration the measurement system and measurement methods must undergo a series of changes and adaptations including the type of excitation signal, techniques for eliminating...

  1. Isolated lower mesospheric echoes seen by medium frequency radar at 70° N, 19° E

    Directory of Open Access Journals (Sweden)

    C. M. Hall

    2006-01-01

    Full Text Available We have noted sporadic instances of strong isolated reflections of medium frequency (MF radar waves from the mesosphere from as low as 50 km altitude and have devised a set of criteria for isolating these apparently anomalous echoes from those normally occurring from progressive partial reflections in the D-region. The object of this study is to map the occurrences of such echoes facilitating comparisons with other observations. For example, the similarity and simultaneity of the echo structure for the 20 January 2005 with VHF radar results presented by Lübken et al. (2006 are particularly striking. In presenting a number of such echo events since 2001 selected from the MF radar dataset (which spans 1997 to present, we find that virtually all echo occurrences coincide with enhanced solar proton fluxes suggesting that substantial ionisation of the mesosphere is a necessary condition. Strong partial reflections of the radio wave in the lower mesosphere combined with seasonally varying total absorption higher up, thus giving false impressions of lower mesospheric layers preferentially in winter, constitute a scenario consistent with our observations.

  2. Instantaneous Real-Time Kinematic Decimeter-Level Positioning with BeiDou Triple-Frequency Signals over Medium Baselines

    Directory of Open Access Journals (Sweden)

    Xiyang He

    2015-12-01

    Full Text Available Many applications, such as marine navigation, land vehicles location, etc., require real time precise positioning under medium or long baseline conditions. In this contribution, we develop a model of real-time kinematic decimeter-level positioning with BeiDou Navigation Satellite System (BDS triple-frequency signals over medium distances. The ambiguities of two extra-wide-lane (EWL combinations are fixed first, and then a wide lane (WL combination is reformed based on the two EWL combinations for positioning. Theoretical analysis and empirical analysis is given of the ambiguity fixing rate and the positioning accuracy of the presented method. The results indicate that the ambiguity fixing rate can be up to more than 98% when using BDS medium baseline observations, which is much higher than that of dual-frequency Hatch-Melbourne-Wübbena (HMW method. As for positioning accuracy, decimeter level accuracy can be achieved with this method, which is comparable to that of carrier-smoothed code differential positioning method. Signal interruption simulation experiment indicates that the proposed method can realize fast high-precision positioning whereas the carrier-smoothed code differential positioning method needs several hundreds of seconds for obtaining high precision results. We can conclude that a relatively high accuracy and high fixing rate can be achieved for triple-frequency WL method with single-epoch observations, displaying significant advantage comparing to traditional carrier-smoothed code differential positioning method.

  3. The Reciprocal Pascal Matrix

    OpenAIRE

    Richardson, Thomas M.

    2014-01-01

    The reciprocal Pascal matrix is the Hadamard inverse of the symmetric Pascal matrix. We show that the ordinary matrix inverse of the reciprocal Pascal matrix has integer elements. The proof uses two factorizations of the matrix of super Catalan numbers.

  4. Electromagnetic Field and Lumped Circuit Analysis of Planar Transformer at Medium Frequency for Converter Application

    Directory of Open Access Journals (Sweden)

    Chengjian Lian

    2017-06-01

    Full Text Available High frequency planar transformer is a new type of transformer that operates at high frequency. Its significance is proved through its miniaturised features, high power density and other performances. The design of planar transformer needs to consider several fundamental factors, including core material, dimension of layers and winding pattern. As the volume decreases, extra attentions need to be paid in power losses and safety requirements. Different converter topologies, with planar transformer integrated, are also investigated and simulated for maximising the overall efficiency of conversion. Overall, the use of planar transformer in converters can bring several benefits, and, hence, there is a strong interest of comprehending its structure and high frequency behaviours.

  5. Electromyogram median power frequency in dynamic exercise at medium exercise intensities

    NARCIS (Netherlands)

    Ament, W; Bonga, GJJ; Hof, AL; Verkerke, GJ

    The electromyogram (EMG) median power Frequency of the calf muscles was investigated during an exhausting treadmill exercise and a 20-min recovery period. The exercise was an uphill run at a speed of 5 km . h(-1) and a gradient of 20%. During exercise there was no decrease of EMG median power

  6. Pressure reciprocity calibration of a MEMS microphone.

    Science.gov (United States)

    Wagner, Randall P; Fick, Steven E

    2017-09-01

    This article reports the first use of the pressure reciprocity technique to calibrate a micro-electromechanical system (MEMS) microphone. This standardized primary calibration method is conventionally used to calibrate laboratory standard microphones. Results for the pressure reciprocity calibration of a MEMS microphone and two laboratory standard microphones are presented for the frequency range 100-10 000 Hz. Because the amplifier in the MEMS microphone package prevents reciprocal operation, this microphone was used only as a receiver of sound. A description of the procedure is presented along with checks of the measurement results and data regarding the uncertainties of these results.

  7. Low-frequency pulse profile variation in PSR B2217+47: evidence for echoes from the interstellar medium

    Science.gov (United States)

    Michilli, D.; Hessels, J. W. T.; Donner, J. Y.; Grießmeier, J.-M.; Serylak, M.; Shaw, B.; Stappers, B. W.; Verbiest, J. P. W.; Deller, A. T.; Driessen, L. N.; Stinebring, D. R.; Bondonneau, L.; Geyer, M.; Hoeft, M.; Karastergiou, A.; Kramer, M.; Osłowski, S.; Pilia, M.; Sanidas, S.; Weltevrede, P.

    2018-02-01

    We have observed a complex and continuous change in the integrated pulse profile of PSR B2217+47, manifested as additional components trailing the main peak. These transient components are detected over 6 years at 150 MHz using the LOw Frequency ARray (LOFAR), but they are not seen in contemporaneous Lovell observations at 1.5 GHz. We argue that propagation effects in the ionized interstellar medium (IISM) are the most likely cause. The putative structures in the IISM causing the profile variation are roughly half-way between the pulsar and the Earth and have transverse radii R ˜ 30 AU. We consider different models for the structures. Under the assumption of spherical symmetry, their implied average electron density is \\overline{n}_e ˜ 100 cm-3. Since PSR B2217+47 is more than an order of magnitude brighter than the average pulsar population visible to LOFAR, similar profile variations would not have been identified in most pulsars, suggesting that subtle profile variations in low-frequency profiles might be more common than we have observed to date. Systematic studies of these variations at low frequencies can provide a new tool to investigate the proprieties of the IISM and the limits to the precision of pulsar timing.

  8. Performance Analysis of a Medium Frequency Offshore Grid for Identification Of Vessels Sailing on High Density Maritime European Routes

    Directory of Open Access Journals (Sweden)

    López Alfonso

    2017-12-01

    Full Text Available The paper analyses the performance of an Automatic Vessel Identification System on Medium Frequency (AVISOMEF, which works with the Grid Method (GM on high density maritime European routes using real data and uniformly distributed data. Compared to other systems, AVISOMEF is a novelty, as it is not a satellite system, nor is it limited by a given coverage distance, in contrast to the Automatic Identification System (AIS, though in exceptional circumstances it leans towards it. To perform the analysis, special simulation software was developed. Moreover, a number of maritime routes along with their traffic density data were selected for the study. For each route, two simulations were performed, the first of which based on the uniform traffic distribution along the route, while the second one made use of real AIS data positioning of vessels sailing on the selected routes. The obtained results for both simulations made the basis for formulating conclusions regarding the capacity of selected routes to support AVISOMEF.

  9. On Reciprocal Causation in the Evolutionary Process.

    Science.gov (United States)

    Svensson, Erik I

    2018-01-01

    Recent calls for a revision of standard evolutionary theory (SET) are based partly on arguments about the reciprocal causation. Reciprocal causation means that cause-effect relationships are bi-directional, as a cause could later become an effect and vice versa. Such dynamic cause-effect relationships raise questions about the distinction between proximate and ultimate causes, as originally formulated by Ernst Mayr. They have also motivated some biologists and philosophers to argue for an Extended Evolutionary Synthesis (EES). The EES will supposedly expand the scope of the Modern Synthesis (MS) and SET, which has been characterized as gene-centred, relying primarily on natural selection and largely neglecting reciprocal causation. Here, I critically examine these claims, with a special focus on the last conjecture. I conclude that reciprocal causation has long been recognized as important by naturalists, ecologists and evolutionary biologists working in the in the MS tradition, although it it could be explored even further. Numerous empirical examples of reciprocal causation in the form of positive and negative feedback are now well known from both natural and laboratory systems. Reciprocal causation have also been explicitly incorporated in mathematical models of coevolutionary arms races, frequency-dependent selection, eco-evolutionary dynamics and sexual selection. Such dynamic feedback were already recognized by Richard Levins and Richard Lewontin in their bok The Dialectical Biologist . Reciprocal causation and dynamic feedback might also be one of the few contributions of dialectical thinking and Marxist philosophy in evolutionary theory. I discuss some promising empirical and analytical tools to study reciprocal causation and the implications for the EES. Finally, I briefly discuss how quantitative genetics can be adapated to studies of reciprocal causation, constructive inheritance and phenotypic plasticity and suggest that the flexibility of this approach

  10. A Randomized Clinical Trial Comparing the Effectiveness of Electroacupuncture versus Medium-Frequency Electrotherapy for Discogenic Sciatica

    Directory of Open Access Journals (Sweden)

    Xue Zhang

    2017-01-01

    Full Text Available Objective. To investigate the short- and long-term effects of electroacupuncture (EA compared with medium-frequency electrotherapy (MFE on chronic discogenic sciatica. Methods. One hundred participants were randomized into two groups to receive EA (n=50 or MFE (n=50 for 4 weeks. A 28-week follow-up of the two groups was performed. The primary outcome measure was the average leg pain intensity. The secondary outcome measures were the low back pain intensity, Oswestry Disability Index (ODI, patient global impression (PGI, drug use frequency, and EA acceptance. Results. The mean changes in the average leg pain numerical rating scale (NRS scores were 2.30 (1.86–2.57 and 1.06 (0.62–1.51 in the EA and MFE groups at week 4, respectively. The difference was significant (P<0.001. The long-term follow-up resulted in significant differences. The average leg pain NRS scores decreased by 2.12 (1.70–2.53 and 0.36 (−0.05–0.78 from baseline in the EA and MFE groups, respectively, at week 28. However, low back pain intensity and PGI did not differ significantly at week 4. No serious adverse events occurred. Conclusions. EA showed greater short-term and long-term benefits for chronic discogenic sciatica than MFE, and the effect of EA was superior to that of MFE. The study findings warrant verification. This trial was registered under identifier ChiCTR-IPR-15006370.

  11. Reciprocity in EMI-EMC

    Science.gov (United States)

    Coren, Richard L.

    This paper reviews the basis of and errors in interpreting the law of reciprocity, and applies it to conducted and to radiated EMI-EMC. Conditions for reciprocity include reversibility and passivity of elements in the reciprocal system. The law is expressed in circuit form and the reciprocal signals are clearly distinguished. Symmetric and asymmetric line filters are used as examples of reciprocity in conducted interference. It is shown that an incompletely shielded circuit can be regarded as an antenna, allowing one to establish radiation reciprocity between it and a measuring antenna. Some difficulties encountered in EMI-EMC measurements, that give the impression of reciprocity being violated, are discussed.

  12. submitter Development of a 100 kW, 12.5 kV, 22 kHz and 30 kV insulated medium frequency transformer for compact and reliable medium voltage power conversion

    CERN Document Server

    Isler, Stephane; Aguglia, Davide; Bonnin, Xavier Abel

    2017-01-01

    This paper presents the critical design aspects addressed during the development of a 100 kW, 12.5 kV, 22 kHz, and 30 kV insulated medium frequency transformer used in a power converter. The transformers are used in a resonant multilevel converter topology producing HV DC voltage from a three phase 400 V AC industrial grid. The power converter is used to supply radio frequency systems in particle accelerators. Considerations about material selection, dielectric, magnetic and thermal design are discussed and experimental results on the full scale transformer and power converter are presented.

  13. Modulational instability of ultra-low-frequency shear dust Alfvén waves in a plasma medium of positive and negatively charged dust fluids

    International Nuclear Information System (INIS)

    Mamun, A. A.

    2014-01-01

    The propagation of finite amplitude ultra-low-frequency shear dust Alfvén (SDA) waves, and their modulational instability in a magnetized plasma medium of positive and negatively charged dust fluids have been theoretically investigated by using the reductive perturbation method. The derivative nonlinear Schrödinger equation is derived to examine the stability analysis of such SDA waves. It is found that the SDA waves propagating in such an opposite polarity dust plasma medium are modulationally unstable, and that the instability criterion and the growth rate of these unstable SDA waves in such a novel opposite polarity dust plasma medium are found to be significantly different from those in electron–ion or electron–positron plasma media. The implications of the present investigation in different space environments and laboratory devices are briefly discussed.

  14. An Approximate Treatment of Reflection Coefficient in the Phased Beam Tracing Method for the Simulation of Enclosed Sound Fields at Medium Frequencies

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho; Ih, Jeong-Guon; Rindel, Jens Holger

    2008-01-01

    The phased beam tracing method (PBTM) was suggested as a medium-frequency simulation technique for the calculation of impulse response, although main assumptions of geometric acoustics still hold. The phased method needs the reflection coefficient for characterizing the acoustic property of a sur......The phased beam tracing method (PBTM) was suggested as a medium-frequency simulation technique for the calculation of impulse response, although main assumptions of geometric acoustics still hold. The phased method needs the reflection coefficient for characterizing the acoustic property...... of a surface and the complex wave number for describing the propagation characteristics. In this study, two types of approximate real reflection coefficients derived from the measured absorption coefficient were tested for a practical applicability. As a test example, pressure impulse responses and energy...

  15. Reciprocity, World Prices and Welfare

    DEFF Research Database (Denmark)

    Raimondos-Møller, Pascalis; Woodland, Alan D.

    it is possible to find tariff reforms that are consistent with both reciprocity and constant world prices, these reforms do not follow from the reciprocity condition, but rather from the requirement of unchanged world prices. We propose an alternative reciprocity rule that is guaranteed to raise the welfare...

  16. Cutting efficiency of Reciproc and waveOne reciprocating instruments.

    Science.gov (United States)

    Plotino, Gianluca; Giansiracusa Rubini, Alessio; Grande, Nicola M; Testarelli, Luca; Gambarini, Gianluca

    2014-08-01

    The aim of the present study was to evaluate the cutting efficiency of 2 new reciprocating instruments, Reciproc and WaveOne. Twenty-four new Reciproc R25 and 24 new WaveOne Primary files were activated by using a torque-controlled motor (Silver Reciproc) and divided into 4 groups (n = 12): group 1, Reciproc activated by Reciproc ALL program; group 2, Reciproc activated by WaveOne ALL program; group 3, WaveOne activated by Reciproc ALL program; and group 4, WaveOne activated by WaveOne ALL program. The device used for the cutting test consisted of a main frame to which a mobile plastic support for the handpiece is connected and a stainless steel block containing a Plexiglas block (inPlexiglass, Rome, Italy) against which the cutting efficiency of the instruments was tested. The length of the block cut in 1 minute was measured in a computerized program with a precision of 0.1 mm. Means and standard deviations of each group were calculated, and data were statistically analyzed with 1-way analysis of variance and Bonferroni test (P instruments used with their proper reciprocating motion presented a statistically significant higher cutting efficiency than WaveOne instruments used with their proper reciprocating motion (P instruments (P > .05). Reciproc instruments demonstrated statistically higher cutting efficiency than WaveOne instruments. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  17. The Role of Friendship Reciprocity in University Freshmen's Alcohol Consumption.

    Science.gov (United States)

    Giese, Helge; Stok, F Marijn; Renner, Britta

    2017-07-01

    The similarity of friends in the frequency and quantity of alcohol consumption is explored. During their first semester, 57 psychology freshmen indicated weekly drinking frequency and quantity and nominated the three peers of this group they liked most. These nominations were then used to derive the weekly alcohol consumption of friends that either did or did not reciprocate a nomination. Multilevel modeling of weekly variations showed that individuals' drinking frequency was similar to peers who reciprocated a friendship (b = 0.15, p = .001), but not to non-reciprocating peers (b = -0.01, p = .720). In contrast, weekly variation in quantity of individual students' drinking was similar to both reciprocating (b = 0.11, p = .018) and non-reciprocating peers' drinking (b = 0.10, p = .014). Yet across all weeks, quantity tended only to be similar to non-reciprocating peers (b = 0.49, p = .020). Freshmen might spend drinking time with peers who reciprocate a friendship, but are similar regarding the quantity of drinks consumed to all people they find interesting. Thus, alcohol consumption is used strategically for social purposes. This social purpose should also be acknowledged in alcohol-reduction interventions. © 2017 The International Association of Applied Psychology.

  18. MULTI-FLUID APPROACH TO HIGH-FREQUENCY WAVES IN PLASMAS. I. SMALL-AMPLITUDE REGIME IN FULLY IONIZED MEDIUM

    Energy Technology Data Exchange (ETDEWEB)

    Martínez-Gómez, David; Soler, Roberto; Terradas, Jaume, E-mail: david.martinez@uib.es [Departament de Física, Universitat de les Illes Balears, E-07122, Palma de Mallorca (Spain)

    2016-12-01

    Ideal magnetohydrodynamics (MHD) provides an accurate description of low-frequency Alfvén waves in fully ionized plasmas. However, higher-frequency waves in many plasmas of the solar atmosphere cannot be correctly described by ideal MHD and a more accurate model is required. Here, we study the properties of small-amplitude incompressible perturbations in both the low- and the high-frequency ranges in plasmas composed of several ionized species. We use a multi-fluid approach and take into account the effects of collisions between ions and the inclusion of Hall’s term in the induction equation. Through the analysis of the corresponding dispersion relations and numerical simulations, we check that at high frequencies ions of different species are not as strongly coupled as in the low-frequency limit. Hence, they cannot be treated as a single fluid. In addition, elastic collisions between the distinct ionized species are not negligible for high-frequency waves, since an appreciable damping is obtained. Furthermore, Coulomb collisions between ions remove the cyclotron resonances and the strict cutoff regions, which are present when collisions are not taken into account. The implications of these results for the modeling of high-frequency waves in solar plasmas are discussed.

  19. Wave activity (planetary, tidal) throughout the middle atmosphere (20-100km) over the CUJO network: Satellite (TOMS) and Medium Frequency (MF) radar observations

    OpenAIRE

    A. H. Manson; C. E. Meek; T. Chshyolkova; S. K. Avery; D. Thorsen; J. W. MacDougall; W. Hocking; Y. Murayama; K. Igarashi

    2005-01-01

    Planetary and tidal wave activity in the tropopause-lower stratosphere and mesosphere-lower thermosphere (MLT) is studied using combinations of ground-based (GB) and satellite instruments (2000-2002). The relatively new MFR (medium frequency radar) at Platteville (40° N, 105° W) has provided the opportunity to create an operational network of middle-latitude MFRs, stretching from 81° W-142° E, which provides winds and tides 70-100km. CUJO (Canada U.S. Japan Opp...

  20. Reciprocating magnetic refrigerator

    Science.gov (United States)

    Johnson, D. L.

    1985-05-01

    A 4 to 15 K magnetic refrigerator to test as an alternative to the Joule-Thomson circuit as the low temperature stage of a 4 to 300 K closed-cycle refrigerator was developed. The reciprocating magnetic refrigerator consists of two matrices of gadolinium gallium garnet spheres located in tandem on a single piston which alternately moves each matrix into a 7 telsa magnetic field. A separate helium gas circuit is used as the heat exchange mechanism for the low and the high temperature extremes of the magnetic refrigerator. Details of the design and results of the initial refrigerator component tests are presented.

  1. The frequency of a disease-causing point mutation in the gene coding for medium-chain acyl-CoA dehydrogenase in sudden infant death syndrome

    DEFF Research Database (Denmark)

    Banner, Jytte; Gregersen, N; Kølvraa, S

    1993-01-01

    syndrome is still a matter of controversy. The present study investigated 120 well-defined cases of sudden infant death syndrome in order to detect the frequency of the most common disease-causing point mutation in the gene coding for medium-chain acyl-CoA dehydrogenase (G985) compared with the frequency...... in the general population. A highly specific polymerase chain reaction assay was applied on dried blood spots. No over-representation of homo- or heterozygosity for G985 appears to exist in such a strictly defined population, for which reason it may be more relevant to look at a broader spectrum of clinical...... presentations of inherited metabolic disorders and examine a wider range of sudden death in infancy....

  2. Structural Behaviour of Reciprocal Structures

    DEFF Research Database (Denmark)

    Parigi, Dario; Kirkegaard, Poul Henning

    2013-01-01

    The present paper focuses on the comparison of several two-dimensional and three-dimensional reciprocal configurations. The goal of such comparison is to analyse the structural behaviour when changing the geometric parameters used to describe the geometry of reciprocal structures.......The present paper focuses on the comparison of several two-dimensional and three-dimensional reciprocal configurations. The goal of such comparison is to analyse the structural behaviour when changing the geometric parameters used to describe the geometry of reciprocal structures....

  3. Using radio frequency and ultrasonic antennas for inspecting pin-type insulators on medium-voltage overhead distribution lines

    Directory of Open Access Journals (Sweden)

    Cícero Lefort Borges

    2013-05-01

    Full Text Available This paper summarises the activities undertaken when using antennas (ultrasound and radiofrequency for identifying insulators in pre-failure state by detecting the noise emitted by the distribution line and correlating this with these insulators (porcelain pin type dielectric breakdown. This has led to developing low-cost maintenance procedures and providing support and criteria for engineer-ing decisions regarding replacing these insulators. The technique used two detectors; a radio frequency detector was used in a first investigation of a particular distribution line, set to 40 MHz and installed on the roof of a moving vehicle. The ultrasound detector was used for inspecting (phases A, B, C each structure (pole selected. Atmospheric conditions had no influence on defining pre-failure insulators (pin type based on the noise detection technique. Pin type insulators emitting noise should be replaced since measurement was made from the ground and near the base of the post.

  4. Planck intermediate results: XVII. Emission of dust in the diffuse interstellar medium from the far-infrared to microwave frequencies

    DEFF Research Database (Denmark)

    Bartlett, J.G.; Cardoso, J.-F.; Delabrouille, J.

    2014-01-01

    of 7500 deg2 centred on the southern Galactic pole. We present a general methodology to study the dust-H i correlation over the sky, including simulations to quantify uncertainties. Our analysis yields four specific results. (1) We map the temperature, submillimetre emissivity, and opacity of the dust per...... it with the far infrared spectral index βFIR derived from greybody fits at higher frequencies, and find a systematic difference, βmm -βFIR = -0.15, which suggests that the dust spectral energy distribution (SED) flattens at v ≤ 353 GHz. (3) We present spectral fits of the microwave emission correlated with Hi...... represent magnetic dipole emission. Alternatively, it could account for an increasing contribution of carbon dust, or a flattening of the emissivity of amorphous silicates, at millimetre wavelengths. These interpretations make different predictions for the dust polarization SED. (4) We analyse the residuals...

  5. Direct reciprocity in structured populations

    NARCIS (Netherlands)

    van Veelen, C.M.; García, J.; Rand, D.G.; Nowak, M.A.

    2012-01-01

    Reciprocity and repeated games have been at the center of attention when studying the evolution of human cooperation. Direct reciprocity is considered to be a powerful mechanism for the evolution of cooperation, and it is generally assumed that it can lead to high levels of cooperation. Here we

  6. Stiffness of sphere–plate contacts at MHz frequencies: dependence on normal load, oscillation amplitude, and ambient medium

    Directory of Open Access Journals (Sweden)

    Jana Vlachová

    2015-03-01

    Full Text Available The stiffness of micron-sized sphere–plate contacts was studied by employing high frequency, tangential excitation of variable amplitude (0–20 nm. The contacts were established between glass spheres and the surface of a quartz crystal microbalance (QCM, where the resonator surface had been coated with either sputtered SiO2 or a spin-cast layer of poly(methyl methacrylate (PMMA. The results from experiments undertaken in the dry state and in water are compared. Building on the shifts in the resonance frequency and resonance bandwidth, the instrument determines the real and the imaginary part of the contact stiffness, where the imaginary part quantifies dissipative processes. The method is closely analogous to related procedures in AFM-based metrology. The real part of the contact stiffness as a function of normal load can be fitted with the Johnson–Kendall–Roberts (JKR model. The contact stiffness was found to increase in the presence of liquid water. This finding is tentatively explained by the rocking motion of the spheres, which couples to a squeeze flow of the water close to the contact. The loss tangent of the contact stiffness is on the order of 0.1, where the energy losses are associated with interfacial processes. At high amplitudes partial slip was found to occur. The apparent contact stiffness at large amplitude depends linearly on the amplitude, as predicted by the Cattaneo–Mindlin model. This finding is remarkable insofar, as the Cattaneo–Mindlin model assumes Coulomb friction inside the sliding region. Coulomb friction is typically viewed as a macroscopic concept, related to surface roughness. An alternative model (formulated by Savkoor, which assumes a constant frictional stress in the sliding zone independent of the normal pressure, is inconsistent with the experimental data. The apparent friction coefficients slightly increase with normal force, which can be explained by nanoroughness. In other words, contact splitting

  7. Belief in reciprocity in a Chinese sample.

    Science.gov (United States)

    Zhang, Zhen; Zhang, Jianxin

    2012-08-01

    Belief in reciprocity refers to a personally internalized faith in the reciprocity norm: that people will return positive and negative interactions or favors in kind. The current study aims to examine the relationship between belief in reciprocity and altruism among a Chinese sample. The Personal Norm of Reciprocity Scale, Trait Forgiveness Scale, Prosocial Tendency Measure, and Altruism Scale were used to assess extent of belief in reciprocity, forgiveness, and prosocial motivation, respectively, among 204 Chinese undergraduates. The results indicated that belief in reciprocity was a partially negative, but not neutral, reciprocity norm for Chinese people. Specifically, belief in reciprocity was positively related to negative reciprocity, but not significantly related to positive reciprocity. Moreover, belief in reciprocity was negatively related to both prosocial tendency and altruistic motivation. The results also indicated that forgiveness largely mediated the effect of belief in reciprocity on altruism. Finally, the implications and limitations of the current study were discussed.

  8. Structural and Mechanical Properties of CrNx Coatings Deposited by Medium-Frequency Magnetron Sputtering with and without Ion Source Assistance

    International Nuclear Information System (INIS)

    Tian, C.X.; He, J.; Wang, H.J.; Fu, D.J.; Yang, B.

    2011-01-01

    CrNx coatings were deposited on Si (100) and WC-Co substrates by a home-made medium-frequency magnetron sputtering system with and without thermal filament ion source assistance. The structure and composition of the coatings were characterized by X-ray diffraction, atomic force microscopy, scanning electron microscopy, and transmission electron microscopy. The mechanical and tribological properties were assessed by microhardness and pin-on-disc testing. The ion source-assisted system showed a deposition rate of 3.88 μm/h, much higher than the value 2.2 μm/h without ion source assistance. The CrNx coatings prepared with ion source assistance exhibited an increase in microhardness (up to 16.3 GPa) and a decrease in friction coefficient (down to 0.48) at the optimized cathode source-to-substrate distance.

  9. Frequency filter of seed x-ray by use of x-ray laser medium. Toward the generation of the temporally coherent x-ray laser

    International Nuclear Information System (INIS)

    Hasegawa, Noboru; Kawachi, Tetsuya; Kishimoto, Maki; Sukegawa, Kouta; Tanaka, Momoko; Ochi, Yoshihiro; Nishikino, Masaharu; Nagashima, Keisuke; Kato, Yoshiaki; Renzhong, Tai

    2009-01-01

    We evaluate the characteristics of a higher-order harmonics light as a seed X-ray amplified through a laser-produced X-ray amplifier. The narrow spectral bandwidth of the X-ray amplifier works as the frequency filter of the seed X-ray, resulting in that only the temporally coherent X-ray is amplified. Experimental investigation using the 29th-order harmonic light of the Ti:sapphire laser at a wavelength of 26.9 nm together with a neon-like manganese X-ray laser medium shows evident spectral narrowing of the seed X-ray and amplification without serious diffraction effects on the propagation of the amplified X-ray beam. This implies that the present combination is potential to realize temporally coherent X-ray lasers, with an expected duration of approximately 400 fs. (author)

  10. Healthy reciprocity in sexual interaction.

    Science.gov (United States)

    Heino, J; Ojanlatva, A

    2000-02-01

    The purpose of the article is to discuss reciprocity in sexual interaction within a couple relationship in which heterosexual orientation is assumed and satisfaction considered. Reciprocity is modelled as an exchange of services which at its best functions as an unwritten contract, a mutual understanding regarding fairness of returned services, and a desire to comply with this principle together with a loved one/lover. An equal treatment of and balanced attitudes towards one another are present together with a just distribution of benefits and concessions or compromises. Reciprocity involves a relative term although healthy reciprocity can be defined for discussion and assessed as a degree of mutual satisfaction. Sexual interaction issues, skills to obtain satisfaction, and sexual and emotional compatibility are important elements in reciprocity. Understandable communication is an essential contributor in the implementation of reciprocity. Conflict-making dialogue should generally be avoided and connotive meanings of words taken into account. Erotophilia-erotophobia dimensions influence both the learning about and attitudes towards sexuality and contribute to personal and professional abilities to assess sexual problems and to attend to them. Erotic touch is a minimum requirement of love making. Sexual orientation, sexual desire, and intimacy influence sexual compatibility. Equity and exchange models are discussed, and a reciprocity model is proposed.

  11. Electromagnetic reciprocity in antenna theory

    CERN Document Server

    Stumpf, Martin

    2018-01-01

    The reciprocity theorem is among the most intriguing concepts in wave field theory and has become an integral part of almost all standard textbooks on electromagnetic (EM) theory. This book makes use of the theorem to quantitatively describe EM interactions concerning general multiport antenna systems. It covers a general reciprocity-based description of antenna systems, their EM scattering properties, and further related aspects. Beginning with an introduction to the subject, Electromagnetic Reciprocity in Antenna Theory provides readers first with the basic prerequisites before offering coverage of the equivalent multiport circuit antenna representations, EM coupling between multiport antenna systems and their EM interactions with scatterers, accompanied with the corresponding EM compensation theorems.

  12. The TORE SUPRA fast reciprocating RF probe

    International Nuclear Information System (INIS)

    Thomas, C.E. Jr.; Harris, J.H.; Haste, G.R.

    1994-01-01

    A fast reciprocating ICRF (Ion Cyclotron Range of Frequencies) probe was installed and operated on TORE SUPRA during 1992/1993. The body of the probe was originally used on the ATF experiment at ORNL. The probe was adapted for use on TORE SUPRA, and mounted on one of the two fast reciprocating probe mounts. The probe consists of two orthogonal single-turn wire loops, mounted so that one loop senses toroidal RF magnetic fields and the other senses poloidal RF magnetic fields. The probe began operation in June, 1993. The probe active area is approximately 5 cm long by 2 cm, and the reciprocating mount has a slow stroke (5 cm/sec) of 30 cm by 2 cm, and the reciprocating mount has a slow stroke (5 cm/sec) of 30 cm and a fast stroke (1.5 m/sec) of about 10 cm. The probe was operated at distances from the plasma edge ranging from 30 cm to -5 cm (i.e., inside the last closed flux surface). The probe design, electronics, calibration, data acquisition and data processing are discussed. First data from the probe are presented as a function of ICRF power, distance from the plasma, loop orientation, and other plasma parameters. Initial data shows parametric instabilities do not play an important role for ICRF in the TORE SUPRA edge and scrape-off-layer (SOL) plasmas. Additionally it is observed that the probe signal has little or no dependence on position in the SOL/plasma edge

  13. Cyclic Fatigue Resistance of Reciproc Blue, Reciproc, and WaveOne Gold Reciprocating Instruments.

    Science.gov (United States)

    Keskin, Cangül; Inan, Uğur; Demiral, Murat; Keleş, Ali

    2017-08-01

    The aim of the present study was to compare the cyclic fatigue resistance of Reciproc Blue R25 (VDW, Munich, Germany) with Reciproc R25 (VDW) and WaveOne Gold Primary (Denstply Maillefer, Ballaigues, Switzerland). Fifteen Reciproc Blue R25, 15 Reciproc R25, and 15 WaveOne Gold Primary instruments were collected and tested in a dynamic cyclic fatigue test device, which has an artificial canal with a 60° angle of curvature and a 5-mm radius of curvature. All instruments were operated until fracture occurred, and time to fracture (TF) and the lengths of the fractured fragments were recorded. The mean and standard deviations of TF and fragment length were calculated for each reciprocating system. TF data were subjected to Kruskal-Wallis 1-way analysis of variance and the Dunn test, whereas fractured fragment length data were subjected to 1-way analysis of variance (P  .05). Reciproc Blue R25 instruments had significantly higher cyclic fatigue resistance than WaveOne Gold and Reciproc R25 instruments. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  14. Influence of vegetation physiognomy, elevation and fire frequency on medium and large mammals in two protected areas of the Espinhaço Range

    Directory of Open Access Journals (Sweden)

    Fernando Ferreira de Pinho

    2017-05-01

    Full Text Available ABSTRACT The objectives of this study were to determine the richness of medium and large mammal species in two protected areas of the Espinhaço Mountain Range, state of Minas Gerais, Brazil; and to investigate the factors affecting the occurrence of those species. To accomplish that we placed 49 camera traps activated by heat and motion at Rio Preto State Park (RPSP and 48 at Sempre Vivas National Park (SVNP. We also collected data on three environmental variables: vegetation physiognomy, elevation and wildfire frequency, to evaluate the influence of these factors on species richness and use intensity (inferred from camera trap detection rate by large mammals. We recorded 23 large mammal species in the two parks combined. The lowest species richness was found at the rupestrian habitat of RPSP, and in the open grasslands of SVNP. The forest and savannah physiognomies were used more intensively by large mammals. Species richness was higher and use was greater at lower elevations of RPSP. In SVNP, fire frequency did not affect species richness or use intensity. The savannah habitat had very similar richness compared to the forests of the two protected areas. The high species richness and use intensity observed in these forest habitats highlights the importance of riparian environments in the Cerrado biome. The highest species richness and use intensity observed at low elevation follows patterns found in the literature, probably due to variation in the vegetation, which results in greater resource availability. Although rupestrian habitats at high elevations of the Espinhaço Range are known to have a high degree of endemism for some taxa, large mammal richness and use were not high in this habitat. These results indicate that the protection of native vegetation at lower elevations is crucial for the long-term conservation of large mammals in the Espinhaço Range.

  15. Effect of thickness on structural, corrosion and mechanical properties of a thin ZrN film deposited by medium frequency (MF) reactive sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Kavitha, Ayyalu; Kannan, Raman [Anna Univ., Dindigul (India). Dept. of Physics; Loganathan, Subramani [Titan Industries, Hosur, Tamilnadu (India). Ion Plating Dept.

    2016-07-01

    Zirconium nitride (ZrN) thin films were prepared on stainless steel (SS) substrates by medium frequency (MF) reactive sputtering with gas ion source (GIS) by varying the deposition time and obtained thickness (t{sub ZrN}) in the range of 1.25 to 3.24 μm. The effect of thickness on the structural and microstructural properties was studied using XRD and AFM. XRD characterization revealed that the texture of the ZrN thin films changes as a function of thickness. Both, the (111) and (200) peak, appear initially and (111) becomes more intense with increasing t{sub ZrN}. AFM imaging revealed that the ZrN thin film coated with t{sub ZrN} ∼ 3.24 μm shows larger grains that are uniformly distributed over the surface. An average hardness value of 19.79 GPa was observed for ZrN thin films having t{sub ZrN} ∼ 3.24 μm. The ZrN thin films having t{sub ZrN} ∼ 3.24 μm exhibits better adhesion strength up to 20 N. The electrochemical polarization studies indicated that the ZrN thin film having larger thickness shows improved corrosion resistance compared to SS in 3.5 % NaCl solution.

  16. Wave activity (planetary, tidal) throughout the middle atmosphere (20-100km) over the CUJO network: Satellite (TOMS) and Medium Frequency (MF) radar observations

    Science.gov (United States)

    Manson, A. H.; Meek, C. E.; Chshyolkova, T.; Avery, S. K.; Thorsen, D.; MacDougall, J. W.; Hocking, W.; Murayama, Y.; Igarashi, K.

    2005-02-01

    Planetary and tidal wave activity in the tropopause-lower stratosphere and mesosphere-lower thermosphere (MLT) is studied using combinations of ground-based (GB) and satellite instruments (2000-2002). The relatively new MFR (medium frequency radar) at Platteville (40° N, 105° W) has provided the opportunity to create an operational network of middle-latitude MFRs, stretching from 81° W-142° E, which provides winds and tides 70-100km. CUJO (Canada U.S. Japan Opportunity) comprises systems at London (43° N, 81° W), Platteville (40° N, 105° W), Saskatoon (52° N, 107° W), Wakkanai (45° N, 142° E) and Yamagawa (31° N, 131° E). It offers a significant 7000-km longitudinal sector in the North American-Pacific region, and a useful range of latitudes (12-14°) at two longitudes. Satellite data mainly involve the daily values of the total ozone column measured by the Earth Probe (EP) TOMS (Total Ozone Mapping Spectrometer) and provide a measure of tropopause-lower stratospheric planetary wave activity, as well as ozone variability. Climatologies of ozone and winds/tides involving frequency versus time (wavelet) contour plots for periods from 2-d to 30-d and the interval from mid 2000 to 2002, show that the changes with altitude, longitude and latitude are very significant and distinctive. Geometric-mean wavelets for the region of the 40° N MFRs demonstrate occasions during the autumn, winter and spring months when there are similarities in the spectral features of the lower atmosphere and at mesopause (85km) heights. Both direct planetary wave (PW) propagation into the MLT, nonlinear PW-tide interactions, and disturbances in MLT tides associated with fluctuations in the ozone forcing are considered to be possible coupling processes. The complex horizontal wave numbers of the longer period oscillations are provided in frequency contour plots for the TOMS satellite data to demonstrate the differences between lower atmospheric and MLT wave motions and their

  17. Wave activity (planetary, tidal throughout the middle atmosphere (20-100km over the CUJO network: Satellite (TOMS and Medium Frequency (MF radar observations

    Directory of Open Access Journals (Sweden)

    A. H. Manson

    2005-02-01

    Full Text Available Planetary and tidal wave activity in the tropopause-lower stratosphere and mesosphere-lower thermosphere (MLT is studied using combinations of ground-based (GB and satellite instruments (2000-2002. The relatively new MFR (medium frequency radar at Platteville (40° N, 105° W has provided the opportunity to create an operational network of middle-latitude MFRs, stretching from 81° W-142° E, which provides winds and tides 70-100km. CUJO (Canada U.S. Japan Opportunity comprises systems at London (43° N, 81° W, Platteville (40° N, 105° W, Saskatoon (52° N, 107° W, Wakkanai (45° N, 142° E and Yamagawa (31° N, 131° E. It offers a significant 7000-km longitudinal sector in the North American-Pacific region, and a useful range of latitudes (12-14° at two longitudes. Satellite data mainly involve the daily values of the total ozone column measured by the Earth Probe (EP TOMS (Total Ozone Mapping Spectrometer and provide a measure of tropopause-lower stratospheric planetary wave activity, as well as ozone variability. Climatologies of ozone and winds/tides involving frequency versus time (wavelet contour plots for periods from 2-d to 30-d and the interval from mid 2000 to 2002, show that the changes with altitude, longitude and latitude are very significant and distinctive. Geometric-mean wavelets for the region of the 40° N MFRs demonstrate occasions during the autumn, winter and spring months when there are similarities in the spectral features of the lower atmosphere and at mesopause (85km heights. Both direct planetary wave (PW propagation into the MLT, nonlinear PW-tide interactions, and disturbances in MLT tides associated with fluctuations in the ozone forcing are considered to be possible coupling processes. The complex horizontal wave numbers of the longer period oscillations are provided in frequency contour plots for the TOMS satellite data to demonstrate the differences between lower atmospheric and MLT wave motions and their

  18. Wave activity (planetary, tidal throughout the middle atmosphere (20-100km over the CUJO network: Satellite (TOMS and Medium Frequency (MF radar observations

    Directory of Open Access Journals (Sweden)

    A. H. Manson

    2005-02-01

    Full Text Available Planetary and tidal wave activity in the tropopause-lower stratosphere and mesosphere-lower thermosphere (MLT is studied using combinations of ground-based (GB and satellite instruments (2000-2002. The relatively new MFR (medium frequency radar at Platteville (40° N, 105° W has provided the opportunity to create an operational network of middle-latitude MFRs, stretching from 81° W-142° E, which provides winds and tides 70-100km. CUJO (Canada U.S. Japan Opportunity comprises systems at London (43° N, 81° W, Platteville (40° N, 105° W, Saskatoon (52° N, 107° W, Wakkanai (45° N, 142° E and Yamagawa (31° N, 131° E. It offers a significant 7000-km longitudinal sector in the North American-Pacific region, and a useful range of latitudes (12-14° at two longitudes. Satellite data mainly involve the daily values of the total ozone column measured by the Earth Probe (EP TOMS (Total Ozone Mapping Spectrometer and provide a measure of tropopause-lower stratospheric planetary wave activity, as well as ozone variability.

    Climatologies of ozone and winds/tides involving frequency versus time (wavelet contour plots for periods from 2-d to 30-d and the interval from mid 2000 to 2002, show that the changes with altitude, longitude and latitude are very significant and distinctive. Geometric-mean wavelets for the region of the 40° N MFRs demonstrate occasions during the autumn, winter and spring months when there are similarities in the spectral features of the lower atmosphere and at mesopause (85km heights. Both direct planetary wave (PW propagation into the MLT, nonlinear PW-tide interactions, and disturbances in MLT tides associated with fluctuations in the ozone forcing are considered to be possible coupling processes. The complex horizontal wave numbers of the longer period oscillations are provided in frequency contour plots for the TOMS satellite data to demonstrate the differences between lower atmospheric

  19. Linear reciprocating wear behaviour of plasma-sprayed Al2O3 ...

    Indian Academy of Sciences (India)

    contact surface, are judged. Results have shown that the wear rate increases with increasing applied load and frequency and that decreases with increasing reciprocating amplitude. Plastic deformation, detachments of unmelted core, ...

  20. Cyclic fatigue of Reciproc and WaveOne reciprocating instruments.

    Science.gov (United States)

    Plotino, G; Grande, N M; Testarelli, L; Gambarini, G

    2012-07-01

    To evaluate the cyclic fatigue resistance of Reciproc(®) and WaveOne(®) instruments in simulated root canals. Two groups of 15 NiTi endodontic instruments of identical tip size of 0.25 mm were tested, group A; Reciproc(®) R25 and group B: WaveOne(®) primary. Cyclic fatigue testing was performed in a stainless steel artificial canal manufactured by reproducing the instrument's size and taper. A simulated root canal with a 60° angle of curvature and 5-mm radius of curvature was constructed for both the instruments tested. The centre of the curvature was 5 mm from the tip of the instrument and the curved segment of the canal was approximately 5 mm in length. The Reciproc(®) instruments were activated using the preset programme specific for the Reciproc(®) instruments, whilst the WaveOne(®) instruments were activated using the preset programme specific for the WaveOne(®) instruments. All instruments were rotated until fracture occurred and the time to fracture (TtF) and the length of the fractured tip were recorded and registered. Means and standard deviations of TtF and fragment length were calculated for each system and data were subjected to Student's t-test (P  0.05) in the mean length of the fractured fragments between the instruments.   Reciproc(®) instruments were associated with a significantly higher cyclic fatigue resistance than WaveOne(®) instruments. © 2012 International Endodontic Journal.

  1. Effect of processing conditions on quality of green beans subjected to reciprocating agitation thermal processing.

    Science.gov (United States)

    Singh, Anika; Singh, Anubhav Pratap; Ramaswamy, Hosahalli S

    2015-12-01

    The effect of reciprocating agitation thermal processing (RA-TP) on quality of canned beans was evaluated in a lab-scale reciprocating retort. Green beans were selected due to their soft texture and sensitive color. Green beans (2.5cm length×0.8cm diameter) were filled into 307×409 cans with carboxylmethylcellulose (0-2%) solutions and processed at different temperatures (110-130°C) and reciprocation frequency (1-3Hz) for predetermined heating times to achieve a process lethality (F o ) of 10min. Products processed at higher temperatures and higher reciprocation frequencies resulted in better retention of chlorophyll and antioxidant activity. However, high reciprocation frequency also resulted in texture losses, with higher breakage of beans, increased turbidity and higher leaching. There was total loss of product quality at the highest agitation speed, especially with low viscosity covering solutions. Results suggest that reciprocating agitation frequency needs to be adequately moderated to get the best quality. For getting best quality, particularly for canned liquid particulate foods with soft particulates and those susceptible to high impact agitation, a gentle reciprocating motion (~1Hz) would be a good compromise. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Reciprocity and Humility in Wonderland

    Science.gov (United States)

    Harry, Beth

    2011-01-01

    This article supports the perspective of Jan Valle regarding the importance of recognizing the subjectivity inherent in decisions about Learning Disabilities. The author argues that the perspectives of both parents and professionals are informed by subjective judgments that must be taken into account in decision making. A reciprocal approach to…

  3. Reciprocity theory of homogeneous reactions

    Science.gov (United States)

    Agbormbai, Adolf A.

    1990-03-01

    The reciprocity formalism is applied to the homogeneous gaseous reactions in which the structure of the participating molecules changes upon collision with one another, resulting in a change in the composition of the gas. The approach is applied to various classes of dissociation, recombination, rearrangement, ionizing, and photochemical reactions. It is shown that for the principle of reciprocity to be satisfied it is necessary that all chemical reactions exist in complementary pairs which consist of the forward and backward reactions. The backward reaction may be described by either the reverse or inverse process. The forward and backward processes must satisfy the same reciprocity equation. Because the number of dynamical variables is usually unbalanced on both sides of a chemical equation, it is necessary that this balance be established by including as many of the dynamical variables as needed before the reciprocity equation can be formulated. Statistical transformation models of the reactions are formulated. The models are classified under the titles free exchange, restricted exchange and simplified restricted exchange. The special equations for the forward and backward processes are obtained. The models are consistent with the H theorem and Le Chatelier's principle. The models are also formulated in the context of the direct simulation Monte Carlo method.

  4. A Theory of Sequential Reciprocity

    NARCIS (Netherlands)

    Dufwenberg, M.; Kirchsteiger, G.

    1998-01-01

    Many experimental studies indicate that people are motivated by reciprocity. Rabin (1993) develops techniques for incorporating such concerns into game theory and economics. His model, however, does not fare well when applied to situations with an interesting dynamic structure (like many

  5. Using reciprocity in Boundary Element Calculations

    DEFF Research Database (Denmark)

    Juhl, Peter Møller; Cutanda Henriquez, Vicente

    2010-01-01

    The concept of reciprocity is widely used in both theoretical and experimental work. In Boundary Element calculations reciprocity is sometimes employed in the solution of computationally expensive scattering problems, which sometimes can be more efficiently dealt with when formulated as the recip......The concept of reciprocity is widely used in both theoretical and experimental work. In Boundary Element calculations reciprocity is sometimes employed in the solution of computationally expensive scattering problems, which sometimes can be more efficiently dealt with when formulated...

  6. Accuracy Investigation of Seismic Reciprocity Using 3D FDM code

    Science.gov (United States)

    Poor Moghaddam, P.; Kasahara, J.

    2003-12-01

    Application of Reciprocity theorem for the problem of marine seismology, which there is numerous shots on the surface and few receivers on the bottom of the ocean, is pivotal. The theory of reciprocity states that we can switch the location and direction of the force source and displacement component between source and receiver without changing in the observation waveform. In this work we performed a numerical simulation. In this simulation we solved wave propagation equations using Finite Difference method, which is 4th order in space and 2nd order in time. To investigate whether the discretizing affects the seismic reciprocity we calculate the 2D velocity components (x, z) respected to two orthogonal force components applied in the x and z directions. Finally reciprocal waveforms are compared. The degree of correlation between the reciprocal components is quite high which shows the excellency of the FDM method, which we employed. The structure for this work is obtained from 2D travel-time inversion estimated in the 1996 survey along North-South line at the Sanriku, Japan Trench. The size of this structure is 143km by 30 km (Fig.1), which discretized by 25 meter gird spacing. The structure is completely heterogeneous which any point has its own value of P-velocity, S-velocity and density. In this structure, two points for investigation of reciprocity are considered (Fig.1). A force source was applied in one point and the velocity measured in another point, further the directions and locations of source and receiver were interchanged to measure its reciprocal one. Figures 2 shows z-velocity component and its reciprocal one and the difference between them when a force source applied in the z-direction. Figures 3 shows x-velocity component and its reciprocal one and the difference between them when a force source applied in the x-direction. The source waveform is considered the Ricker wavelet with central frequency of 5 Hz. To gain faster computational time and

  7. The effect of burst-duty-cycle parameters of medium-frequency alternating current on maximum electrically induced torque of the quadriceps femoris, discomfort, and tolerated current amplitude in professional soccer players.

    Science.gov (United States)

    Liebano, Richard Eloin; Waszczuk, Silas; Corrêa, Juliana Barbosa

    2013-12-01

    Repeated-measures, within-subject crossover trial. The primary objective was to assess the effect of the burst-duty-cycle parameters of medium-frequency alternating current on the maximum electrically induced torque of the quadriceps femoris. The secondary objectives were to evaluate the amount of discomfort tolerated and the maximum current amplitude delivered for each electrical-stimulation condition. Neuromuscular electrical stimulation used for muscle strengthening can improve functional performance. However, the electrical-stimulation parameters to achieve optimal outcomes are still unknown. Previous studies have demonstrated that the characteristics of the burst duty cycle of medium-frequency alternating current influence torque-generation levels and perception of sensory discomfort. The maximum electrically induced torque was assessed with a medium-frequency alternating current, with a carrier frequency of 2500 Hz and a modulated frequency of 50 Hz. The current amplitude was gradually increased to the point of the participant's maximum tolerance level. The testing sequence for the 3 burst duty cycles (20%, 35%, and 50%) was performed in a randomized order. Electrical stimulation using a 20% burst duty cycle produced an electrically induced torque greater than the 35% (P = .01) and 50% (P<.01) burst duty cycles, with no difference between the 35% and 50% burst duty cycles (P = .46). There was no difference in the amount of sensory discomfort produced by the 3 durations of burst duty cycles (P = .34). There was also no difference between the 3 conditions for the maximum current amplitude tolerated (P = .62). The burst duty cycle of 20% of medium-frequency alternating current, compared to burst duty cycles of 35% and 50%, produced higher peak torque of the quadriceps femoris in professional soccer players. There was no difference in discomfort produced and current amplitude tolerated between the different burst-duty-cycle conditions.

  8. Capuchin Monkeys Judge Third-Party Reciprocity

    Science.gov (United States)

    Anderson, James R.; Takimoto, Ayaka; Kuroshima, Hika; Fujita, Kazuo

    2013-01-01

    Increasing interest is being shown in how children develop an understanding of reciprocity in social exchanges and fairness in resource distribution, including social exchanges between third parties. Although there are descriptions of reciprocity on a one-to-one basis in other species, whether nonhumans detect reciprocity and violations of…

  9. Medium-Sized Mammals around a Radioactive Liquid Waste Lagoon at Los Alamos National Laboratory: Uptake of Contaminants and Evaluation of Radio-Frequency Identification Technology

    Energy Technology Data Exchange (ETDEWEB)

    Leslie A. Hansen; Phil R. Fresquez; Rhonda J. Robinson; John D. Huchton; Teralene S. Foxx

    1999-11-01

    Use of a radioactive liquid waste lagoon by medium-sized mammals and levels of tritium, other selected radionuclides, and metals in biological tissues of the animals were documented at Technical Area 53 (TA-53) of Los Alamos National Laboratory during 1997 and 1998. Rock squirrel (Spermophilus variegates), raccoon (Procyon lotor), striped skunk (Mephitis mephitis), and bobcat (Lynx rufus) were captured at TA-53 and at a control site on the Santa Fe National Forest. Captured animals were anesthetized and marked with radio-frequency identification (RFD) tags and/or ear tags. We collected urine and hair samples for tritium and metals (aluminum, antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, and thallium) analyses, respectively. In addition, muscle and bone samples from two rock squirrels collected from each of TA-53, perimeter, and regional background sites were tested for tritium, {sup 137}Cs, {sup 90}Sr, {sup 238}Pu, {sup 239,240}Pu, {sup 241}Am, and total uranium. Animals at TA-53 were monitored entering and leaving the lagoon area using a RFID monitor to read identification numbers from the RFID tags of marked animals and a separate camera system to photograph all animals passing through the monitor. Cottontail rabbit (Sylvilagus spp.), rock squirrel, and raccoon were the species most frequently photographed going through the RFID monitor. Less than half of all marked animals in the lagoon area were detected using the lagoon. Male and female rock squirrels from the lagoon area had significantly higher tritium concentrations compared to rock squirrels from the control area. Metals tested were not significantly higher in rock squirrels from TA-53, although there was a trend toward increased levels of lead in some individuals at TA-53. Muscle and bone samples from squirrels in the lagoon area appeared to have higher levels of tritium, total uranium, and {sup 137}Cs than samples collected from perimeter and

  10. Statistical characterization of high-to-medium frequency mesoscale gravity waves by lidar-measured vertical winds and temperatures in the MLT

    Science.gov (United States)

    Lu, Xian; Chu, Xinzhao; Li, Haoyu; Chen, Cao; Smith, John A.; Vadas, Sharon L.

    2017-09-01

    We present the first statistical study of gravity waves with periods of 0.3-2.5 h that are persistent and dominant in the vertical winds measured with the University of Colorado STAR Na Doppler lidar in Boulder, CO (40.1°N, 105.2°W). The probability density functions of the wave amplitudes in temperature and vertical wind, ratios of these two amplitudes, phase differences between them, and vertical wavelengths are derived directly from the observations. The intrinsic period and horizontal wavelength of each wave are inferred from its vertical wavelength, amplitude ratio, and a designated eddy viscosity by applying the gravity wave polarization and dispersion relations. The amplitude ratios are positively correlated with the ground-based periods with a coefficient of 0.76. The phase differences between the vertical winds and temperatures (φW -φT) follow a Gaussian distribution with 84.2±26.7°, which has a much larger standard deviation than that predicted for non-dissipative waves ( 3.3°). The deviations of the observed phase differences from their predicted values for non-dissipative waves may indicate wave dissipation. The shorter-vertical-wavelength waves tend to have larger phase difference deviations, implying that the dissipative effects are more significant for shorter waves. The majority of these waves have the vertical wavelengths ranging from 5 to 40 km with a mean and standard deviation of 18.6 and 7.2 km, respectively. For waves with similar periods, multiple peaks in the vertical wavelengths are identified frequently and the ones peaking in the vertical wind are statistically longer than those peaking in the temperature. The horizontal wavelengths range mostly from 50 to 500 km with a mean and median of 180 and 125 km, respectively. Therefore, these waves are mesoscale waves with high-to-medium frequencies. Since they have recently become resolvable in high-resolution general circulation models (GCMs), this statistical study provides an important

  11. Using reciprocity in Boundary Element Calculations

    DEFF Research Database (Denmark)

    Juhl, Peter Møller; Cutanda Henriquez, Vicente

    2010-01-01

    The concept of reciprocity is widely used in both theoretical and experimental work. In Boundary Element calculations reciprocity is sometimes employed in the solution of computationally expensive scattering problems, which sometimes can be more efficiently dealt with when formulated as the recip......The concept of reciprocity is widely used in both theoretical and experimental work. In Boundary Element calculations reciprocity is sometimes employed in the solution of computationally expensive scattering problems, which sometimes can be more efficiently dealt with when formulated...... as the reciprocal radiation problem. The present paper concerns the situation of having a point source (which is reciprocal to a point receiver) at or near a discretized boundary element surface. The accuracy of the original and the reciprocal problem is compared in a test case for which an analytical solution...

  12. The Principle of Structural Reciprocity

    DEFF Research Database (Denmark)

    Pugnale, Alberto; Parigi, Dario; Kirkegaard, Poul Henning

    2011-01-01

    This paper deals with the principle of structural reciprocity, considering its origins in both Occidental and Orient culture and aiming to highlight the definition, main peculiarities and interesting aspects of such concept referring to its application to the world of construction. Issues spanning...... from history, form-finding and morphology, structural behaviour and construction techniques are discussed in the paper, which should be considered as a starting point to stimulate future research and design directions/approaches....

  13. CONSTRUCTING AND DERIVING RECIPROCAL TRIGONOMETRIC RELATIONS: A FUNCTIONAL ANALYTIC APPROACH

    OpenAIRE

    Ninness, Chris; Dixon, Mark; Barnes-Holmes, Dermot; Rehfeldt, Ruth Anne; Rumph, Robin; McCuller, Glen; Holland, James; Smith, Ronald; Ninness, Sharon K; McGinty, Jennifer

    2009-01-01

    Participants were pretrained and tested on mutually entailed trigonometric relations and combinatorially entailed relations as they pertained to positive and negative forms of sine, cosine, secant, and cosecant. Experiment 1 focused on training and testing transformations of these mathematical functions in terms of amplitude and frequency followed by tests of novel relations. Experiment 2 addressed training in accordance with frames of coordination (same as) and frames of opposition (reciproc...

  14. Evaluation of reciprocating electromagnetic air pumping for portable PEMFC

    International Nuclear Information System (INIS)

    Kwon, Kilsung; Kang, Ho; Kang, Seongwon; Kim, Daejoong

    2013-01-01

    In this paper, we present a proton exchange membrane fuel cell (PEMFC) integrated with an electromagnetic (EM) air pump. The EM air pump provides the PEMFC with air by reciprocating motions of the permanent magnet attached to a flexible membrane. We performed a parametric study to decide the optimal dimensions of the reciprocating EM air pump. The effects of various operating parameters on the EM air pump were investigated with the root-mean-square (RMS) flow rate and current. A core with a higher relative permeability shows better performance. The RMS current linearly increases with the applied voltage and shows no dependence on the frequency. The RMS flow rate also increases with the voltage. The RMS flow rate per power consumption is highest at the frequency around 20 Hz and decreases as the applied voltage increases. When the reciprocating EM air pump was used to supply air to the portable PEMFC, it was found that the power density of the PEMFC increases with the applied voltage and shows the highest performance at the frequency of 10 Hz. We compared the performance of the PEMFC between the flow meter and the EM air pump used as an air supplier. About 81% of the output power using the flow meter was obtained when the EM air pump is operated at the applied voltage of 5 V. The parasitic power ratio reaches at its minimum value about 0.1 with an EM applied voltage of 0.25V. (paper)

  15. Plasma chemistry of the sealed-off slab CO laser active medium pumped by radio-frequency discharge with liquid-nitrogen-cooled electrodes

    Science.gov (United States)

    Ionin, A. A.; Kozlov, A. Yu.; Seleznev, L. V.; Sinitsyn, D. V.

    2017-09-01

    The long-term time behavior of the output power of a sealed-off cryogenic slab CO laser pumped by a repetitively pulsed RF discharge and operating on the overtone (λ = 2.6-3.5 μm) vibrational-rotational transitions of the CO molecule was studied experimentally. It is shown that adding of an anomalously large amount of oxygen (up to 50% with respect to the CO concentration) to the initial gas mixture CO : He = 1 : 10 leads to a manyfold (by several tens of times) increase in the duration of the laser operating cycle (until lasing failure due to the degradation of the active medium). In this case, the laser life-time without replacement of the active medium reaches 105-106 pulses. Using various diagnostics (including luminescence spectroscopy and IR and UV absorption spectroscopy), regularities in the time-behavior of the concentrations of the main component of the active medium (CO molecules) and the products of plasmachemical reactions (O3, CO2) generated in the discharge gap during the laser operating cycle are revealed. Time correlation between the characteristics of the active medium and the laser output power are analyzed. A phenomenological approach to describing the entirety of plasmachemical, purely chemical, gas-dynamic, and diffusion processes determining the behavior of the laser output characteristics throughout the laser operating cycle is offered.

  16. Reciprocal frame architecture in Japan

    OpenAIRE

    POPOVIC LARSEN, Olga

    2010-01-01

    p. 1866-1876 Reciprocal Frame Structures (RF) are a form of a three-dimensional grillage structure. In their simplest configuration they are formed by placing beams in a closed circuit in which each beam is supported by the preceding beam at the inner end, and by an external wall or ring beam on the outer end. In their more complex configurations gridshell-like structures with a double curvature can be formed. Although RFs have been used in many countries throughout history and are k...

  17. Onsager Reciprocity in Premelting Solids

    KAUST Repository

    Peppin, S. S. L.

    2009-02-01

    The diffusive motion of foreign particles dispersed in a premelting solid is analyzed within the framework of irreversible thermodynamics. We determine the mass diffusion coefficient, thermal diffusion coefficient and Soret coefficient of the particles in the dilute limit, and find good agreement with experimental data. In contrast to liquid suspensions, the unique nature of premelting solids allows us to derive an expression for the Dufour coefficient and independently verify the Onsager reciprocal relation coupling diffusion to the flow of heat. © 2009 Springer Science+Business Media, LLC.

  18. Alternating sums of reciprocal generalized Fibonacci numbers.

    Science.gov (United States)

    Kuhapatanakul, Kantaphon

    2014-01-01

    Recently Holliday and Komatsu extended the results of Ohtsuka and Nakamura on reciprocal sums of Fibonacci numbers to reciprocal sums of generalized Fibonacci numbers. The aim of this work is to give similar results for the alternating sums of reciprocals of the generalized Fibonacci numbers with indices in arithmetic progression. Finally we note our generalizations of some results of Holliday and Komatsu. Primary 11B37; secondary 11B39.

  19. Detecting reciprocity at a global scale

    Science.gov (United States)

    Frank, Morgan R.; Obradovich, Nick; Sun, Lijun; Woon, Wei Lee; LeVeck, Brad L.; Rahwan, Iyad

    2018-01-01

    Reciprocity stabilizes cooperation from the level of microbes all the way up to humans interacting in small groups, but does reciprocity also underlie stable cooperation between larger human agglomerations, such as nation states? Famously, evolutionary models show that reciprocity could emerge as a widespread strategy for achieving international cooperation. However, existing studies have only detected reciprocity-driven cooperation in a small number of country pairs. We apply a new method for detecting mutual influence in dynamical systems to a new large-scale data set that records state interactions with high temporal resolution. Doing so, we detect reciprocity between many country pairs in the international system and find that these reciprocating country pairs exhibit qualitatively different cooperative dynamics when compared to nonreciprocating pairs. Consistent with evolutionary theories of cooperation, reciprocating country pairs exhibit higher levels of stable cooperation and are more likely to punish instances of noncooperation. However, countries in reciprocity-based relationships are also quicker to forgive single acts of noncooperation by eventually returning to previous levels of mutual cooperation. By contrast, nonreciprocating pairs are more likely to exploit each other’s cooperation via higher rates of defection. Together, these findings provide the strongest evidence to date that reciprocity is a widespread mechanism for achieving international cooperation. PMID:29326983

  20. Reciprocally-Rotating Velocity Obstacles

    KAUST Repository

    Giese, Andrew

    2014-05-01

    © 2014 IEEE. Modern multi-agent systems frequently use highlevel planners to extract basic paths for agents, and then rely on local collision avoidance to ensure that the agents reach their destinations without colliding with one another or dynamic obstacles. One state-of-the-art local collision avoidance technique is Optimal Reciprocal Collision Avoidance (ORCA). Despite being fast and efficient for circular-shaped agents, ORCA may deadlock when polygonal shapes are used. To address this shortcoming, we introduce Reciprocally-Rotating Velocity Obstacles (RRVO). RRVO generalizes ORCA by introducing a notion of rotation for polygonally-shaped agents. This generalization permits more realistic motion than ORCA and does not suffer from as much deadlock. In this paper, we present the theory of RRVO and show empirically that it does not suffer from the deadlock issue ORCA has, permits agents to reach goals faster, and has a comparable collision rate at the cost of performance overhead quadratic in the (typically small) user-defined parameter δ.

  1. Low-Frequency Observations of Galactic Supernova Remnants and the Distribution of Low-Density Ionized Gas in the Interstellar Medium

    National Research Council Canada - National Science Library

    Kassim, Namir E

    1989-01-01

    .... These observations are combined with other low-frequency data to derive free-free optical depths toward 47 SNRs and to constrain the physical properties of the ionized gas responsible for the absorption...

  2. Design considerations for a high power, medium frequency transformer for a DC-DC converter stage of a solid state transformer

    OpenAIRE

    Mumuluh, Roland Nshieteh

    2016-01-01

    ii. ABSTRACTIn recent years, the solid state transformer concept has challenged the conventional low frequency transformer. The conventional transformer cannot store energy and its output is easily distorted as a result of perturbations at its input. In same manner, disturbances from the output unit such as harmonics along with reactive power, as well as load transients are reflected back to the input of the conventional transformer. The size of the low frequency transformer is significantly ...

  3. Improving Mathematical Communication Ability and Self Regulation Learning of Junior High Students by Using Reciprocal Teaching

    Science.gov (United States)

    Qohar, Abdul; Sumarmo, Utari

    2013-01-01

    This paper presents the findings from a posttest experiment control group design by using reciprocal teaching, conducted in Indonesia University of Education to investigate students' ability in mathematical communication and self regulated learning. Subject of the study were 254 of 9th grade students from three junior high schools of high, medium,…

  4. Fault detection in reciprocating compressor valves under varying load conditions

    Science.gov (United States)

    Pichler, Kurt; Lughofer, Edwin; Pichler, Markus; Buchegger, Thomas; Klement, Erich Peter; Huschenbett, Matthias

    2016-03-01

    This paper presents a novel approach for detecting cracked or broken reciprocating compressor valves under varying load conditions. The main idea is that the time frequency representation of vibration measurement data will show typical patterns depending on the fault state. The problem is to detect these patterns reliably. For the detection task, we make a detour via the two dimensional autocorrelation. The autocorrelation emphasizes the patterns and reduces noise effects. This makes it easier to define appropriate features. After feature extraction, classification is done using logistic regression and support vector machines. The method's performance is validated by analyzing real world measurement data. The results will show a very high detection accuracy while keeping the false alarm rates at a very low level for different compressor loads, thus achieving a load-independent method. The proposed approach is, to our best knowledge, the first automated method for reciprocating compressor valve fault detection that can handle varying load conditions.

  5. Information seeking and reciprocity: A transformational analysis

    NARCIS (Netherlands)

    Gallucci, M.; Perugini, M.

    2003-01-01

    The motivation to reciprocate is analyzed within the framework of interdependence theory, with focus on the process of transformation of situations. A model of transformation is presented for the motivation to reciprocate and hypotheses regarding allocation behavior and information seeking are

  6. Integral inequalities for self-reciprocal polynomials

    Indian Academy of Sciences (India)

    that is, the coefficients satisfy ak = an−k for k = 0, 1,...,n. We denote the class of self-reciprocal polynomials of order n by Pn. The properties of self-reciprocal polynomials have been studied by several mathemati- cians. We refer to [1–5] and the references given therein. Here, we are concerned with the following interesting ...

  7. Non-reciprocity in nonlinear elastodynamics

    Science.gov (United States)

    Blanchard, Antoine; Sapsis, Themistoklis P.; Vakakis, Alexander F.

    2018-01-01

    Reciprocity is a fundamental property of linear time-invariant (LTI) acoustic waveguides governed by self-adjoint operators with symmetric Green's functions. The break of reciprocity in LTI elastodynamics is only possible through the break of time reversal symmetry on the micro-level, and this can be achieved by imposing external biases, adding nonlinearities or allowing for time-varying system properties. We present a Volterra-series based asymptotic analysis for studying spatial non-reciprocity in a class of one-dimensional (1D), time-invariant elastic systems with weak stiffness nonlinearities. We show that nonlinearity is neither necessary nor sufficient for breaking reciprocity in this class of systems; rather, it depends on the boundary conditions, the symmetries of the governing linear and nonlinear operators, and the choice of the spatial points where the non-reciprocity criterion is tested. Extension of the analysis to higher dimensions and time-varying systems is straightforward from a mathematical point of view (but not in terms of new non-reciprocal physical phenomena), whereas the connection of non-reciprocity and time irreversibility can be studied as well. Finally, we show that suitably defined non-reciprocity measures enable optimization, and can provide physical understanding of the nonlinear effects in the dynamics, enabling one to establish regimes of "maximum nonlinearity." We highlight the theoretical developments by means of a numerical example.

  8. Reciprocity Outperforms Conformity to Promote Cooperation.

    Science.gov (United States)

    Romano, Angelo; Balliet, Daniel

    2017-10-01

    Evolutionary psychologists have proposed two processes that could give rise to the pervasiveness of human cooperation observed among individuals who are not genetically related: reciprocity and conformity. We tested whether reciprocity outperformed conformity in promoting cooperation, especially when these psychological processes would promote a different cooperative or noncooperative response. To do so, across three studies, we observed participants' cooperation with a partner after learning (a) that their partner had behaved cooperatively (or not) on several previous trials and (b) that their group members had behaved cooperatively (or not) on several previous trials with that same partner. Although we found that people both reciprocate and conform, reciprocity has a stronger influence on cooperation. Moreover, we found that conformity can be partly explained by a concern about one's reputation-a finding that supports a reciprocity framework.

  9. Attenuation of low-frequency underwater sound using an array of air-filled balloons and comparison to effective medium theory.

    Science.gov (United States)

    Lee, Kevin M; Wilson, Preston S; Wochner, Mark S

    2017-12-01

    The ultimate goal of this work is to accurately predict the attenuation through a collection of large (on the order of 10-cm-radius) tethered encapsulated bubbles used in underwater noise abatement systems. Measurements of underwater sound attenuation were performed during a set of lake experiments, where a low-frequency compact electromechanical sound source was surrounded by different arrays of encapsulated bubbles with various individual bubbles sizes and void fractions. The measurements were compared with an existing predictive model [Church, J. Acoust. Soc. Am. 97, 1510-1521 (1995)] of the dispersion relation for linear propagation in liquid containing encapsulated bubbles. Although the model was originally intended to describe ultrasound contrast agents, it is evaluated here for large bubbles, and hence low frequencies, as a design tool for future underwater noise abatement systems, and there is good quantitative agreement between the observations and the model.

  10. Reciprocity and Ethical Tuberculosis Treatment and Control.

    Science.gov (United States)

    Silva, Diego S; Dawson, Angus; Upshur, Ross E G

    2016-03-01

    This paper explores the notion of reciprocity in the context of active pulmonary and laryngeal tuberculosis (TB) treatment and related control policies and practices. We seek to do three things: First, we sketch the background to contemporary global TB care and suggest that poverty is a key feature when considering the treatment of TB patients. We use two examples from TB care to explore the role of reciprocity: isolation and the use of novel TB drugs. Second, we explore alternative means of justifying the use of reciprocity through appeal to different moral and political theoretical traditions (i.e., virtue ethics, deontology, and consequentialism). We suggest that each theory can be used to provide reasons to take reciprocity seriously as an independent moral concept, despite any other differences. Third, we explore general meanings and uses of the concept of reciprocity, with the primary intention of demonstrating that it cannot be simply reduced to other more frequently invoked moral concepts such as beneficence or justice. We argue that reciprocity can function as a mid-level principle in public health, and generally, captures a core social obligation arising once an individual or group is burdened as a result of acting for the benefit of others (even if they derive a benefit themselves). We conclude that while more needs to be explored in relation to the theoretical justification and application of reciprocity, sufficient arguments can be made for it to be taken more seriously as a key principle within public health ethics and bioethics more generally.

  11. ADVANCED RECIPROCATING COMPRESSION TECHNOLOGY (ARCT)

    Energy Technology Data Exchange (ETDEWEB)

    Danny M. Deffenbaugh; Klaus Brun; Ralph E. Harris; J. Pete Harrell; Robert J. Mckee; J. Jeffrey Moore; Steven J. Svedeman; Anthony J. Smalley; Eugene L. Broerman; Robert A Hart; Marybeth G. Nored; Ryan S. Gernentz; Shane P. Siebenaler

    2005-12-01

    The U.S. natural gas pipeline industry is facing the twin challenges of increased flexibility and capacity expansion. To meet these challenges, the industry requires improved choices in gas compression to address new construction and enhancement of the currently installed infrastructure. The current fleet of installed reciprocating compression is primarily slow-speed integral machines. Most new reciprocating compression is and will be large, high-speed separable units. The major challenges with the fleet of slow-speed integral machines are: limited flexibility and a large range in performance. In an attempt to increase flexibility, many operators are choosing to single-act cylinders, which are causing reduced reliability and integrity. While the best performing units in the fleet exhibit thermal efficiencies between 90% and 92%, the low performers are running down to 50% with the mean at about 80%. The major cause for this large disparity is due to installation losses in the pulsation control system. In the better performers, the losses are about evenly split between installation losses and valve losses. The major challenges for high-speed machines are: cylinder nozzle pulsations, mechanical vibrations due to cylinder stretch, short valve life, and low thermal performance. To shift nozzle pulsation to higher orders, nozzles are shortened, and to dampen the amplitudes, orifices are added. The shortened nozzles result in mechanical coupling with the cylinder, thereby, causing increased vibration due to the cylinder stretch mode. Valve life is even shorter than for slow speeds and can be on the order of a few months. The thermal efficiency is 10% to 15% lower than slow-speed equipment with the best performance in the 75% to 80% range. The goal of this advanced reciprocating compression program is to develop the technology for both high speed and low speed compression that will expand unit flexibility, increase thermal efficiency, and increase reliability and integrity

  12. Two distinct neural mechanisms underlying indirect reciprocity.

    Science.gov (United States)

    Watanabe, Takamitsu; Takezawa, Masanori; Nakawake, Yo; Kunimatsu, Akira; Yamasue, Hidenori; Nakamura, Mitsuhiro; Miyashita, Yasushi; Masuda, Naoki

    2014-03-18

    Cooperation is a hallmark of human society. Humans often cooperate with strangers even if they will not meet each other again. This so-called indirect reciprocity enables large-scale cooperation among nonkin and can occur based on a reputation mechanism or as a succession of pay-it-forward behavior. Here, we provide the functional and anatomical neural evidence for two distinct mechanisms governing the two types of indirect reciprocity. Cooperation occurring as reputation-based reciprocity specifically recruited the precuneus, a region associated with self-centered cognition. During such cooperative behavior, the precuneus was functionally connected with the caudate, a region linking rewards to behavior. Furthermore, the precuneus of a cooperative subject had a strong resting-state functional connectivity (rsFC) with the caudate and a large gray matter volume. In contrast, pay-it-forward reciprocity recruited the anterior insula (AI), a brain region associated with affective empathy. The AI was functionally connected with the caudate during cooperation occurring as pay-it-forward reciprocity, and its gray matter volume and rsFC with the caudate predicted the tendency of such cooperation. The revealed difference is consistent with the existing results of evolutionary game theory: although reputation-based indirect reciprocity robustly evolves as a self-interested behavior in theory, pay-it-forward indirect reciprocity does not on its own. The present study provides neural mechanisms underlying indirect reciprocity and suggests that pay-it-forward reciprocity may not occur as myopic profit maximization but elicit emotional rewards.

  13. Alcohol expectancies, perceived norms, and drinking behavior among college students: examining the reciprocal determinism hypothesis.

    Science.gov (United States)

    Wardell, Jeffrey D; Read, Jennifer P

    2013-03-01

    Social learning mechanisms, such as descriptive norms for drinking behavior (norms) and positive alcohol expectancies (PAEs), play a major role in college student alcohol use. According to the principle of reciprocal determinism (Bandura, 1977), norms and PAEs should be reciprocally associated with alcohol use, each influencing one another over time. However, the nature of these prospective relationships for college students is in need of further investigation. This study provided the first examination of the unique reciprocal associations among norms, PAEs, and drinking together in a single model. PAEs become more stable with age, whereas norms are likely to be more dynamic upon college entry. Thus, we hypothesized that alcohol use would show stronger reciprocal associations with norms than with PAEs for college students. Students (N = 557; 67% women) completed online measures of PAEs, norms, and quantity and frequency of alcohol use in September of their first (T1), second (T2), and third (T3) years of college. Reciprocal associations were analyzed using a cross-lagged panel design. PAEs had unidirectional influences on frequency and quantity of alcohol use, with no prospective effects from alcohol use to PAEs. Reciprocal associations were observed between norms and alcohol use, but only for quantity and not for frequency. Specifically, drinking quantity prospectively predicted quantity norms and quantity norms prospectively predicted drinking quantity. This effect was observed across both years in the model. These findings support the reciprocal determinism hypothesis for norms but not for PAEs in college students and may help to inform norm-based interventions. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  14. Low and then high frequency oscillations of distinct right cortical networks are progressively enhanced by medium and long term Satyananda Yoga meditation practice

    Directory of Open Access Journals (Sweden)

    John eThomas

    2014-06-01

    Full Text Available Meditation proficiency is related to trait-like (learned effects on brain function, developed over time. Previous studies show increases in EEG power in lower frequency bands (theta, alpha in experienced meditators in both meditation states and baseline conditions. Higher gamma band power has been found in advanced Buddhist meditators, yet it is not known if this occurs in Yoga meditation practices. This study used eLORETA to compare differences in cortical source activity underlying scalp EEG from intermediate (mean experience 4 years and advanced (mean experience 30 years Australian meditators from the Satyananda Yoga tradition during a body-steadiness meditation, mantra meditation and non-meditation mental calculation condition. Intermediate Yoga meditators showed greater source activity in low frequencies (particularly theta and alpha1 during mental calculation, body-steadiness and mantra meditation. A similar spatial pattern of significant differences was found in all conditions but the number of significant voxels was double during body-steadiness and mantra meditation than in the non-meditation (calculation condition. These differences were greatest in right (R superior frontal and R precentral gyri and extended back to include the R parietal and occipital lobes. Advanced Yoga meditators showed greater activity in high frequencies (beta and especially gamma in all conditions but greatly expanded during meditation practice. Across all conditions (meditation and non-meditation differences were greatest in the same regions; R insula, R inferior frontal gyrus and R anterior temporal lobe. Distinct R core networks were identified in alpha1 (8-10 Hz and gamma (25-42 Hz bands respectively. The voxels recruited to these networks greatly expanded during meditation practice to include homologous regions of the left hemisphere. Functional interpretation parallels traditionally described stages of development in Yoga proficiency.

  15. Reciprocity Effects in the Trust Game

    Directory of Open Access Journals (Sweden)

    Alexander Smith

    2013-07-01

    Full Text Available I use data from a previous experiment for classifying subjects based on their behavior in the trust game. Prior literature defines a “reciprocity effect” as the tendency for Second Movers to return proportions increasing in the amounts that they receive. In the data that I use, 31% of Second Movers show reciprocity effects, 31% are neutral, and 25% consistently free-ride, indicating that the aggregate reciprocity effect for the sample as a whole is attributable to a minority of the subjects.

  16. Morphogenesis of Kinetic Reciprocal Frames

    DEFF Research Database (Denmark)

    Parigi, Dario; Sassone, Mario

    2011-01-01

    Kinetic structures in civil engineering and architecture gained considerable more attention in the very recent years as a practical solution to face time dependant performances. Realized projects are mostly bridges, retractable roofs, while in architecture the trend follows the category of intera......Kinetic structures in civil engineering and architecture gained considerable more attention in the very recent years as a practical solution to face time dependant performances. Realized projects are mostly bridges, retractable roofs, while in architecture the trend follows the category...... (RF) were studied in the past as a practical solution to span distances with shorter elements. Leonardo da Vinci discovered interesting RF patterns and studied three dimensional arch structures for bridges. RF are generally defined as structures that forms closed circuits of forces, and where elements...... joins in intermediate points. In the present paper we will describe a new subset of kinetic structures based on reciprocal frames topology and pin-slot constraint, a connection where a pin is constrained to move along a slot, and to rotate around its axis. The first step in obtaining a kinetic...

  17. Spite and Reciprocity in Auctions

    Directory of Open Access Journals (Sweden)

    Yoshikazu Ikeda

    2011-09-01

    Full Text Available The paper presents a complete information model of bidding in second price sealed-bid and ascending-bid (English auctions, in which potential buyers know the unit valuation of other bidders and may spitefully prefer that their rivals earn a lower surplus. Bidders with spiteful preferences should overbid in equilibrium when they know their rival has a higher value than their own, and bidders with a higher value underbid to reciprocate the spiteful overbidding of the lower value bidders. The model also predicts different bidding behavior in second price as compared to ascending-bid auctions. The paper also presents experimental evidence broadly consistent with the model. In the complete information environment, lower value bidders overbid more than higher value bidders, and they overbid more frequently in the second price auction than in the ascending price auction. Overall, the lower value bidder submits bids that exceed value about half the time. These patterns are not found in the incomplete information environment, consistent with the model.

  18. NO Removal with Repetitive Discharges Caused by Reciprocal Traveling Wave Voltage Pulse in a Coaxial Cable

    Science.gov (United States)

    Yamaga, Keisuke; Kadowaki, Kazunori; Nishimoto, Sakae; Kitani, Isamu

    This paper describes experimental results of NO removal using barrier discharges produced by a reciprocal pulse generator. When a coaxial cable is charged and then grounded at one end of the cable without any resistance, a reciprocal traveling voltage pulse is repeatedly applied to a barrier-type reactor at the opposite end with a change in its polarity. 50% streamer initiation voltage for the reciprocal pulse generator was much smaller than that with the self-matched pulse generator having a matching resistance. The reason for the low initiation voltage in the reciprocal pulse was that space charges which accumulated on the barrier surface during cable charging had an effect on field enhancement in the reactor after the first polarity reversal. High speed photographs of discharge light produced by the reciprocal pulse showed that the voltage oscillation caused by one switching induced alternate propagation of positive and negative streamers with a very high frequency. In measurements of NO concentration, the reciprocal pulse generator gave a better performance for NO removal ratio than the self-matched pulse generator even though the stored energy in the recipocal pulse generator was very low.

  19. Synchronized conductivity modulation to realize broadband lossless magnetic-free non-reciprocity.

    Science.gov (United States)

    Dinc, Tolga; Tymchenko, Mykhailo; Nagulu, Aravind; Sounas, Dimitrios; Alu, Andrea; Krishnaswamy, Harish

    2017-10-06

    Recent research has explored the spatiotemporal modulation of permittivity to break Lorentz reciprocity in a manner compatible with integrated-circuit fabrication. However, permittivity modulation is inherently weak and accompanied by loss due to carrier injection, particularly at higher frequencies, resulting in large insertion loss, size, and/or narrow operation bandwidths. Here, we show that the presence of absorption in an integrated electronic circuit may be counter-intuitively used to our advantage to realize a new generation of magnet-free non-reciprocal components. We exploit the fact that conductivity in semiconductors provides a modulation index several orders of magnitude larger than permittivity. While directly associated with loss in static systems, we show that properly synchronized conductivity modulation enables loss-free, compact and extremely broadband non-reciprocity. We apply these concepts to obtain a wide range of responses, from isolation to gyration and circulation, and verify our findings by realizing a millimeter-wave (25 GHz) circulator fully integrated in complementary metal-oxide-semiconductor technology.Optical non-reciprocity achieved through refractive index modulation can have its challenges and limitations. Here, Dinc et al. introduce the concept of non-reciprocity based on synchronized spatio-temporal modulation of conductivity to achieve different types of non-reciprocal functionality.

  20. Persistent junctional reciprocating tachycardia in the fetus

    NARCIS (Netherlands)

    Oudijk, M. A.; Stoutenbeek, P.; Sreeram, N.; Visser, G. H. A.; Meijboom, E. J.

    2003-01-01

    Persistent junctional reciprocating tachycardia (PJRT) tends to be a persistent arrhythmia and requires aggressive therapeutic management. Diagnosis and management of this infrequently occurring tachycardia in the fetus at an early stage is of importance for the prevention of congestive heart

  1. The House Money Effect and Negative Reciprocity

    OpenAIRE

    Katarína Danková; Maroš Servátka

    2014-01-01

    In the vast majority of laboratory experiments documenting the existence of reciprocity subjects are endowed with windfall funds. In many environments with salient fairness considerations such endowments are known to inflate subjects’ other-regarding behavior, thereby creating a so-called “house money effect.” This suggests that laboratory experiments might also overestimate reciprocal behavior. In this study we identify two reasons why the source of endowment might matter for negative recipr...

  2. Balanced Reciprocal Translocations Detected at Amniocentesis

    Directory of Open Access Journals (Sweden)

    Chih-Ping Chen

    2010-12-01

    Conclusion: Balanced reciprocal translocations detected at amniocentesis may be associated with fetal anomalies in cases of concomitant aneuploidy, de novo X-autosome translocation or de novo CCR. Genetic counseling of a de novo simple reciprocal translocation at amniocentesis remains difficult because approximately one-fourth of the parents opt for termination of the pregnancy, and detailed ultrasonography and array comparative genomic hybridization are helpful for parental counseling under such circumstances.

  3. Free-Form Kinetic Reciprocal System

    DEFF Research Database (Denmark)

    Parigi, Dario; Sassone, Mario

    2011-01-01

    Kinetic Reciprocal System (KRS) are innovative moveable structures based on the principle of reciprocity [1] with internal pin-slot constraints [2]. The analysis of KRS kinematic and static determinacy is developed through the construction of kinematic matrices, accordingly with [3...... of the required kinetic behaviour and its validity has been tested on physical models. A set of case studies and possible applications are described, focusing on the morphologic variety of results and on the efficiency of the kinetic performance....

  4. Wave Activity (Planetary, Tidal) throughout the Middle Atmoshere (25-100 km) over the CUJO Network: Satellite and Medium Frequency (MF) Radar Observations

    Science.gov (United States)

    Manson, A.; Meek, C.; Chshyolkova, T.; Avery, S.; Thorsen, D.; MacDougall, J.; Hocking, W.; Murayama, Y.; Igarashi, K.

    Planetary and tidal wave activity in the mesosphere-lower thermosphere (MLT), and assessment of wave activity sources in the lower atmosphere, are studied using combinations of ground based (GB) and satellite instruments (2000-2002). CUJO (Canada U.S. Japan Opportunity) comprises MF radar (MFR) systems at London (43°N, 81°W), Platteville (40°N, 105°W), Saskatoon (52°N, 107°W), Wakkanai (45°N, 142°E) and Yamagawa (31°N, 131°E). It offers a significant mid-latitude 7,000 km longitudinal sector in the North American-Pacific region, and a useful range of latitudes (12-14°) at two longitudes. CUJO provides winds and tides 70-100km. Satellite data include the daily values of the total ozone column measured by the Earth Probe (EP) TOMS (Total Ozone Mapping Spectrometer) and provides a measure of tropopause-lower stratospheric planetary wave activity as well as ozone variability. The so-called UKMO data (an assimilation system) are used for correlative purposes with the TOMS data. Climatologies of ozone and winds/tides involving frequency versus time (wavelet) contour plots for periods from 2-d to 30-d and the interval from mid 2000 to 2002, show that the changes with altitude, longitude and latitude are very significant and distinctive. Geometric-mean wavelets for the region of the 40°N MFRs demonstrate occasions during the autumn, winter and spring months when there are similarities in the spectral features of the lower atmosphere and at mesopause (85km) heights. Both direct planetary wave (PW) propagation into the MLT, non-linear PW-tide interactions, and disturbances in MLT tides associated with fluctuations in the ozone forcing are considered to be possible coupling processes. The complex horizontal wave numbers of the longer period oscillations are provided in frequency contour plots for the TOMS and UKMO data to demonstrate the differences between lower atmospheric and MLT wave motions and their directions of propagation.

  5. Experimental Study of Reciprocating Friction between Rape Stalk and Bionic Nonsmooth Surface Units

    Directory of Open Access Journals (Sweden)

    Zheng Ma

    2015-01-01

    Full Text Available Background. China is the largest producer of rape oilseed in the world; however, the mechanization level of rape harvest is relatively low, because rape materials easily adhere to the cleaning screens of combine harvesters, resulting in significant cleaning losses. Previous studies have shown that bionic nonsmooth surface cleaning screens restrain the adhesion of rape materials, but the underlying mechanisms remain unclear. Objective. The reciprocating friction between rape stalk and bionic nonsmooth metal surface was examined. Methods. The short-time Fourier transform method was used to discriminate the stable phase of friction signals and the stick-lag distance was defined to analyze the stable reciprocating friction in a phase diagram. Results. The reciprocating friction between rape stalk and metal surface is a typical stick-slip friction, and the bionic nonsmooth metal surfaces with concave or convex units reduced friction force with increasing reciprocating frequency. The results also showed that the stick-lag distance of convex surface increased with reciprocating frequency, which indicated that convex surface reduces friction force more efficiently. Conclusions. We suggest that bionic nonsmooth surface cleaning screens, especially with convex units, restrain the adhesion of rape materials more efficiently compared to the smooth surface cleaning screens.

  6. The neural correlates of reciprocity are sensitive to prior experience of reciprocity.

    Science.gov (United States)

    Cáceda, Ricardo; Prendes-Alvarez, Stefania; Hsu, Jung-Jiin; Tripathi, Shanti P; Kilts, Clint D; James, G Andrew

    2017-08-14

    Reciprocity is central to human relationships and is strongly influenced by multiple factors including the nature of social exchanges and their attendant emotional reactions. Despite recent advances in the field, the neural processes involved in this modulation of reciprocal behavior by ongoing social interaction are poorly understood. We hypothesized that activity within a discrete set of neural networks including a putative moral cognitive neural network is associated with reciprocity behavior. Nineteen healthy adults underwent functional magnetic resonance imaging scanning while playing the trustee role in the Trust Game. Personality traits and moral development were assessed. Independent component analysis was used to identify task-related functional brain networks and assess their relationship to behavior. The saliency network (insula and anterior cingulate) was positively correlated with reciprocity behavior. A consistent array of brain regions supports the engagement of emotional, self-referential and planning processes during social reciprocity behavior. Published by Elsevier B.V.

  7. Extending The Calibration In The Underwater Sound Reference Division (USRD) Reciprocity Coupler To Incorporate Phase

    Science.gov (United States)

    2016-09-01

    have a much higher impedance than the acoustic medium. 3. No air or any other low impedance material can be present in the coupler. The hydrophone...pressure ram controls the hydrostatic pressure in the coupler fluid, castor oil. Chamber temperature is controlled by heating or cooling distilled water...differential amplifier 4 USRD H48 Reciprocity Coupler 5 Ithaco 1201 6 NI BMC-2110 and NI-6259 7 Laptop Computer with Matlab 8 Pressure Ram 9 Neslab Endocal

  8. The extended reciprocity: Strong belief outperforms persistence.

    Science.gov (United States)

    Kurokawa, Shun

    2017-05-21

    The existence of cooperation is a mysterious phenomenon and demands explanation, and direct reciprocity is one key potential explanation for the evolution of cooperation. Direct reciprocity allows cooperation to evolve for cooperators who switch their behavior on the basis of information about the opponent's behavior. Here, relevant to direct reciprocity is information deficiency. When the opponent's last move is unknown, how should players behave? One possibility is to choose cooperation with some default probability without using any further information. In fact, our previous paper (Kurokawa, 2016a) examined this strategy. However, there might be beneficial information other than the opponent's last move. A subsequent study of ours (Kurokawa, 2017) examined the strategy which uses the own last move when the opponent's last move is unknown, and revealed that referring to the own move and trying to imitate it when information is absent is beneficial. Is there any other beneficial information else? How about strong belief (i.e., have infinite memory and believe that the opponent's behavior is unchanged)? Here, we examine the evolution of strategies with strong belief. Analyzing the repeated prisoner's dilemma game and using evolutionarily stable strategy (ESS) analysis against an invasion by unconditional defectors, we find the strategy with strong belief is more likely to evolve than the strategy which does not use information other than the opponent player's last move and more likely to evolve than the strategy which uses not only the opponent player's last move but also the own last move. Strong belief produces the extended reciprocity and facilitates the evolution of cooperation. Additionally, we consider the two strategies game between strategies with strong belief and any strategy, and we consider the four strategies game in which unconditional cooperators, unconditional defectors, pessimistic reciprocators with strong belief, and optimistic reciprocators with

  9. Enhanced additive manufacturing with a reciprocating platen

    Energy Technology Data Exchange (ETDEWEB)

    Lind, Randall F.; Blue, Craig A.; Love, Lonnie J.; Post, Brian K.; Lloyd, Peter D.

    2018-02-06

    An additive manufacturing extrusion head that includes a heated nozzle for accepting a feedstock and extruding the feedstock onto a substrate at a deposition plane, the nozzle having a longitudinal extrusion axis. A reciprocating platen surrounds the nozzle, the platen operable to reciprocate along the extrusion axis at or above the deposition plane as the nozzle extrudes feedstock onto the substrate; and wherein the platen flattens the extruded feedstock such that it does not protrude above the deposition plane as the extrusion head traverses over the substrate.

  10. Cooperation under indirect reciprocity and imitative trust.

    Directory of Open Access Journals (Sweden)

    Serguei Saavedra

    Full Text Available Indirect reciprocity, a key concept in behavioral experiments and evolutionary game theory, provides a mechanism that allows reciprocal altruism to emerge in a population of self-regarding individuals even when repeated interactions between pairs of actors are unlikely. Recent empirical evidence show that humans typically follow complex assessment strategies involving both reciprocity and social imitation when making cooperative decisions. However, currently, we have no systematic understanding of how imitation, a mechanism that may also generate negative effects via a process of cumulative advantage, affects cooperation when repeated interactions are unlikely or information about a recipient's reputation is unavailable. Here we extend existing evolutionary models, which use an image score for reputation to track how individuals cooperate by contributing resources, by introducing a new imitative-trust score, which tracks whether actors have been the recipients of cooperation in the past. We show that imitative trust can co-exist with indirect reciprocity mechanisms up to a threshold and then cooperation reverses -revealing the elusive nature of cooperation. Moreover, we find that when information about a recipient's reputation is limited, trusting the action of third parties towards her (i.e. imitating does favor a higher collective cooperation compared to random-trusting and share-alike mechanisms. We believe these results shed new light on the factors favoring social imitation as an adaptive mechanism in populations of cooperating social actors.

  11. Integral Inequalities for Self-Reciprocal Polynomials

    Indian Academy of Sciences (India)

    Annual Meetings · Mid Year Meetings · Discussion Meetings · Public Lectures · Lecture Workshops · Refresher Courses · Symposia · Live Streaming. Home; Journals; Proceedings – Mathematical Sciences; Volume 120; Issue 2. Integral Inequalities for Self-Reciprocal Polynomials. Horst Alzer. Volume 120 Issue 2 April 2010 ...

  12. Integral inequalities for self-reciprocal polynomials

    Indian Academy of Sciences (India)

    Annual Meetings · Mid Year Meetings · Discussion Meetings · Public Lectures · Lecture Workshops · Refresher Courses · Symposia · Live Streaming. Home; Journals; Proceedings – Mathematical Sciences; Volume 120; Issue 2. Integral Inequalities for Self-Reciprocal Polynomials. Horst Alzer. Volume 120 Issue 2 April 2010 ...

  13. Generalized reciprocal method applied in processing seismic ...

    African Journals Online (AJOL)

    A geophysical investigation was carried out at Shika, near Zaria, using seismic refraction method; with the aim of analyzing the data obtained using the generalized reciprocal method (GRM). The technique is for delineating undulating refractors at any depth from in-line seismic refraction data consisting of forward and ...

  14. Reciprocity, Materialism and Welfare: An Evolutionary Model

    DEFF Research Database (Denmark)

    Poulsen, Anders

    2001-01-01

    We analyze preference evolution in a simple bargaining situation. Preferences for reciprocity, who sustain a conflict-free outcome, may be viable if players have enough information about the opponent's preferences. However, depending on the initial starting point preference evolution can in gener...

  15. The transition probabilities of the reciprocity model

    NARCIS (Netherlands)

    Snijders, T.A.B.

    1999-01-01

    The reciprocity model is a continuous-time Markov chain model used for modeling longitudinal network data. A new explicit expression is derived for its transition probability matrix. This expression can be checked relatively easily. Some properties of the transition probabilities are given, as well

  16. Human-animal amity and reciprocity

    NARCIS (Netherlands)

    Wissenburg, M.L.J.

    2014-01-01

    Animals are now widely accepted as subjects of justice: not equal but deserving equal consideration; not free but deserving liberties (that is, selfconstraining human duties). But liberty and equality are not all there is to a flourishing society – how about amity and reciprocity? Isn’t a minimal

  17. Reciprocal Teaching. What Works Clearinghouse Intervention Report

    Science.gov (United States)

    What Works Clearinghouse, 2013

    2013-01-01

    "Reciprocal teaching" is an instructional method designed to help teach reading comprehension skills to students with adequate decoding proficiency. During initial instructional sessions, the teacher introduces four comprehension strategies: summarizing, questioning, clarifying, and predicting. Then, the teacher and student read several…

  18. 37 CFR 11.24 - Reciprocal discipline.

    Science.gov (United States)

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Reciprocal discipline. 11.24... discipline. (a) Notification of OED Director. Within thirty days of being publicly censured, publicly... USPTO Director. The OED Director shall, in addition, without Committee on Discipline authorization, file...

  19. Isoenzymatic variability in tropical maize populations under reciprocal recurrent selection

    Directory of Open Access Journals (Sweden)

    Pinto Luciana Rossini

    2003-01-01

    Full Text Available Maize (Zea mays L. is one of the crops in which the genetic variability has been extensively studied at isoenzymatic loci. The genetic variability of the maize populations BR-105 and BR-106, and the synthetics IG-3 and IG-4, obtained after one cycle of a high-intensity reciprocal recurrent selection (RRS, was investigated at seven isoenzymatic loci. A total of twenty alleles were identified, and most of the private alleles were found in the BR-106 population. One cycle of reciprocal recurrent selection (RRS caused reductions of 12% in the number of alleles in both populations. Changes in allele frequencies were also observed between populations and synthetics, mainly for the Est 2 locus. Populations presented similar values for the number of alleles per locus, percentage of polymorphic loci, and observed and expected heterozygosities. A decrease of the genetic variation values was observed for the synthetics as a consequence of genetic drift effects and reduction of the effective population sizes. The distribution of the genetic diversity within and between populations revealed that most of the diversity was maintained within them, i.e. BR-105 x BR-106 (G ST = 3.5% and IG-3 x IG-4 (G ST = 4.0%. The genetic distances between populations and synthetics increased approximately 21%. An increase in the genetic divergence between the populations occurred without limiting new selection procedures.

  20. A 1.5 GFLOPS Reciprocal Unit for Computer Graphics

    DEFF Research Database (Denmark)

    Nannarelli, Alberto; Rasmussen, Morten Sleth; Stuart, Matthias Bo

    2006-01-01

    The reciprocal operation 1/d is a frequent operation performed in graphics processors (GPUs). In this work, we present the design of a radix-16 reciprocal unit based on the algorithm combining the traditional digit-by-digit algorithm and the approximation of the reciprocal by one Newton-Raphson i...

  1. Reciprocity, social ties, and competition in markets for experience goods

    DEFF Research Database (Denmark)

    Huck, Steffen; Tyran, Jean-Robert

    2007-01-01

    Reciprocal customers may disproportionately improve the performance of markets for experience goods. Reciprocal customers reward (punish) firms for providing good (bad) quality by upholding (terminating) the customer relation. This may induce firms to provide good quality which, in turn, may induce...... a positive externality for non-reciprocal customers who would, in the absence of reciprocal types, face market breakdown. This efficiency-enhancing effect of reciprocity is boosted when there are social ties between consumers and competition between firms. The existence of social ties or competition alone...

  2. Exposure to Hedione Increases Reciprocity in Humans

    Directory of Open Access Journals (Sweden)

    Sebastian Berger

    2017-05-01

    Full Text Available Cooperation among unrelated humans is frequently regarded as a defining feature in the evolutionary success of our species. Whereas, much research has addressed the strategic and cognitive mechanisms that underlie cooperation, investigations into chemosensory processes have received very limited research attention. To bridge that gap, we build on recent research that has identified the chemically synthesized odorant Hedione (HED as a ligand for the putative human pheromone receptor (VN1R1 expressed in the olfactory mucosa, and hypothesize that exposure to HED may increase reciprocity. Applying behavioral economics paradigms, the present research shows that exposure to the ligand causes differentiated behavioral effects in reciprocal punishments (Study 1 as well as rewards (Study 2, two types of behaviors that are frequently regarded as essential for the development and maintenance of cooperation.

  3. Reciprocity as a Foundation of Financial Economics.

    Science.gov (United States)

    Johnson, Timothy C

    This paper argues that the subsistence of the fundamental theorem of contemporary financial mathematics is the ethical concept 'reciprocity'. The argument is based on identifying an equivalence between the contemporary, and ostensibly 'value neutral', Fundamental Theory of Asset Pricing with theories of mathematical probability that emerged in the seventeenth century in the context of the ethical assessment of commercial contracts in a framework of Aristotelian ethics. This observation, the main claim of the paper, is justified on the basis of results from the Ultimatum Game and is analysed within a framework of Pragmatic philosophy. The analysis leads to the explanatory hypothesis that markets are centres of communicative action with reciprocity as a rule of discourse. The purpose of the paper is to reorientate financial economics to emphasise the objectives of cooperation and social cohesion and to this end, we offer specific policy advice.

  4. Reciprocal Trading of Different Commodities in Norway Rats.

    Science.gov (United States)

    Schweinfurth, Manon K; Taborsky, Michael

    2018-02-19

    The prevalence of reciprocal cooperation in non-human animals is hotly debated [1, 2]. Part of this dispute rests on the assumption that reciprocity means paying like with like [3]. However, exchanges between social partners may involve different commodities and services. Hitherto, there is no experimental evidence that animals other than primates exchange different commodities among conspecifics based on the decision rules of direct reciprocity. Here, we show that Norway rats (Rattus norvegicus) apply direct reciprocity rules when exchanging two different social services: food provisioning and allogrooming. Focal rats were made to experience partners either cooperating or non-cooperating in one of the two commodities. Afterward, they had the opportunity to reciprocate favors by the alternative service. Test rats traded allogrooming against food provisioning, and vice versa, thereby acting by the rules of direct reciprocity. This might indicate that reciprocal altruism among non-human animals is much more widespread than currently assumed. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Robustness of Long Span Reciprocal Timber Structures

    DEFF Research Database (Denmark)

    Balfroid, Nathalie; Kirkegaard, Poul Henning; Sassone, Mario SASSONE

    2011-01-01

    engineer may take necessary steps to design robust structures that are insensitive to accidental circumstances. The present paper makes a discussion of such robustness issues related to the future development of reciprocal timber structures. The paper concludes that these kind of structures can have...... a potential as long span timber structures in real projects if they are carefully designed with respect to the overall robustness strategies....

  6. Reciprocal mass tensor : a general form

    International Nuclear Information System (INIS)

    Roy, C.L.

    1978-01-01

    Using the results of earlier treatment of wave packets, a general form of reciprocal mass tensor has been obtained. The elements of this tensor are seen to be dependent on momentum as well as space coordinates of the particle under consideration. The conditions under which the tensor would reduce to the usual space-independent form, are discussed and the impact of the space-dependence of this tensor on the motion of Bloch electrons, is examined. (author)

  7. Integral inequalities for self-reciprocal polynomials

    Indian Academy of Sciences (India)

    Integral inequalities for self-reciprocal polynomials. HORST ALZER. Morsbacher Str. 10, D-51545 Waldbröl, Germany. E-mail: H.Alzer@gmx.de. MS received 14 November 2007. Abstract. Let n ≥ 1 be an integer and let Pn be the class of polynomials P of degree at most n satisfying znP(1/z) = P (z) for all z ∈ C. Moreover, ...

  8. Grooming reciprocity in male Tibetan macaques.

    Science.gov (United States)

    Xia, Dong-Po; Li, Jin-Hua; Garber, Paul A; Matheson, Megan D; Sun, Bing-Hua; Zhu, Yong

    2013-10-01

    In several primate species, adult males are reported to compete for access to reproductive partners as well as forming affiliative and cohesive social bonds based on the exchange of goods or services. We hypothesized that among a broad set of fitness-maximizing strategies, grooming can be used by individual adult males to enhance social relationships through reciprocity and/or through the interchange of grooming for a different but equivalent good or service. We used focal animal sampling and continuously recorded dyadic grooming and agonistic interactions to test a series of predictions regarding male social interactions in a free-ranging group of Tibetan macaques (Macaca thibetana) at Huangshan, China. During the non-mating season or between males of similar rank throughout the year, grooming effort given was matched by grooming effort received. However, lower ranking males groomed higher ranking males at a greater rate and/or for a longer duration during both the mating and non-mating periods. We found that higher ranking males directed less aggression towards males with whom they formed a frequent grooming partnership, indicating that grooming received was interchanged for increased social tolerance. These data suggest that individual male Tibetan macaques employ alternative social strategies associated with grooming reciprocity or interchange depending on dominance rank and rates of aggression, and highlight the importance of both biological markets and grooming reciprocity as behavioral mechanisms used by resident adult males to form and maintain affiliative social bonds. © 2013 Wiley Periodicals, Inc.

  9. Diferentes tempos de eletroestimulação neuromuscular (eenm de média frequência (kotz em cães Different times of neuromuscular electrical stimulation medium frequency (kotz in dogs

    Directory of Open Access Journals (Sweden)

    Charles Pelizzari

    2011-09-01

    Full Text Available O objetivo desta pesquisa foi empregar a estimulação elétrica neuromuscular (EENM de média frequência no músculo quadríceps femoral de cães com atrofia muscular induzida, avaliar o ganho de massa muscular e comparar a EENM sob diferentes tempos de tratamento. Foram utilizados oito cães, pesando entre 15 e 25kg e distribuídos aleatoriamente em dois grupos denominados de GI (30minutos e GII (60minutos. Para a indução da atrofia muscular, a articulação do joelho direito foi imobilizada por 30 dias por transfixação percutânea tipo II. Após a retirada do aparelho de imobilização, foi realizada a EENM nos cães dos grupos GI e GII três vezes por semana, com intervalo mínimo de 48 horas entre cada sessão, pelo período de 60 dias. Foram mensuradas a perimetria da coxa, goniometria dos joelhos, atividade da enzima creatina-quinase (CK e morfometria das fibras musculares do vasto lateral em cortes transversais colhido mediante a biópsia muscular. Não houve diferença quanto aos valores da perimetria da coxa e atividade da enzima CK. A goniometria revelou significância (PThe aim of this study was to use medium frequency Neuromuscular Electrical Stimulation (NMES in femoral quadriceps muscle of dogs with induced muscular atrophy to evaluate the occurrence of mass gain in these muscles and to compare NMES in different periods of treatment. Eight dogs, weighing between 15 and 25kg, were randomly placed in two groups: GI (NMES for 30min, GII, (NMES for 60min. For the muscular atrophy induction, the right knee was immobilized for 30 days by the percutaneous transfixation type II method. NMES was carried out in the dogs of which groups, three times a week, in between 48h each session, in a period of 60 days. The parameters measured were: thigh perimetry, knee goniometry, creatine kinase (CK enzyme activity and morphometry of the muscular fibers in transversal cuts of the vastus lateralis muscle, collected through a muscular biopsy

  10. Reciprocity on the hardwood: passing patterns among professional basketball players.

    Directory of Open Access Journals (Sweden)

    Robb Willer

    Full Text Available Past theory and research view reciprocal resource sharing as a fundamental building block of human societies. Most studies of reciprocity dynamics have focused on trading among individuals in laboratory settings. But if motivations to engage in these patterns of resource sharing are powerful, then we should observe forms of reciprocity even in highly structured group environments in which reciprocity does not clearly serve individual or group interests. To this end, we investigated whether patterns of reciprocity might emerge among teammates in professional basketball games. Using data from logs of National Basketball Association (NBA games of the 2008-9 season, we estimated a series of conditional logistic regression models to test the impact of different factors on the probability that a given player would assist another player in scoring a basket. Our analysis found evidence for a direct reciprocity effect in which players who had "received" assists in the past tended to subsequently reciprocate their benefactors. Further, this tendency was time-dependent, with the probability of repayment highest soon after receiving an assist and declining as game time passed. We found no evidence for generalized reciprocity - a tendency to "pay forward" assists - and only very limited evidence for indirect reciprocity - a tendency to reward players who had sent others many assists. These findings highlight the power of reciprocity to shape human behavior, even in a setting characterized by extensive planning, division of labor, quick decision-making, and a focus on inter-group competition.

  11. Reinforcement learning account of network reciprocity.

    Directory of Open Access Journals (Sweden)

    Takahiro Ezaki

    Full Text Available Evolutionary game theory predicts that cooperation in social dilemma games is promoted when agents are connected as a network. However, when networks are fixed over time, humans do not necessarily show enhanced mutual cooperation. Here we show that reinforcement learning (specifically, the so-called Bush-Mosteller model approximately explains the experimentally observed network reciprocity and the lack thereof in a parameter region spanned by the benefit-to-cost ratio and the node's degree. Thus, we significantly extend previously obtained numerical results.

  12. Reciprocal translocations in Saccharomyces cerevisiae formed by nonhomologous end joining.

    OpenAIRE

    Yu, Xin; Gabriel, Abram

    2004-01-01

    Reciprocal translocations are common in cancer cells, but their creation is poorly understood. We have developed an assay system in Saccharomyces cerevisiae to study reciprocal translocation formation in the absence of homology. We induce two specific double-strand breaks (DSBs) simultaneously on separate chromosomes with HO endonuclease and analyze the subsequent chromosomal rearrangements among surviving cells. Under these conditions, reciprocal translocations via nonhomologous end joining ...

  13. Intention-Based Reciprocity and the Hidden Costs of Control

    OpenAIRE

    Ferdinand von Siemens

    2011-01-01

    Empirical research suggests that - rather than improving incentives - exerting control can reduce workers' performance by eroding motivation. The present paper shows that intention-based reciprocity can cause such motivational crowding-out if individuals differ in their propensity for reciprocity and preferences are private information. Not being controlled might then be considered to be kind, because not everybody reciprocates not being controlled with high effort. This argument stands in co...

  14. Neural correlate of human reciprocity in social interactions

    Directory of Open Access Journals (Sweden)

    Shiro eSakaiya

    2013-12-01

    Full Text Available Reciprocity plays a key role maintaining cooperation in society. However, little is known about the neural process that underpins human reciprocity during social interactions. Our neuroimaging study manipulated partner identity (computer, human and strategy (random, tit-for-tat in repeated prisoner’s dilemma games and investigated the neural correlate of reciprocal interaction with humans. Reciprocal cooperation with humans but exploitation of computers by defection was associated with activation in the left amygdala. Amygdala activation was also positively and negatively correlated with a preference change for human partners following tit-for-tat and random strategies, respectively. The correlated activation represented the intensity of positive feeling toward reciprocal and negative feeling toward non-reciprocal partners, and so reflected reciprocity in social interaction. Reciprocity in social interaction, however, might plausibly be misinterpreted and so we also examined the neural coding of insight into the reciprocity of partners. Those with and without insight revealed differential brain activation across the reward-related circuitry (i.e., the right middle dorsolateral prefrontal cortex and dorsal caudate and theory of mind (ToM regions (i.e., ventromedial prefrontal cortex [VMPFC] and precuneus. Among differential activations, activation in the precuneus, which accompanied deactivation of the VMPFC, was specific to those without insight into human partners who were engaged in a tit-for-tat strategy. This asymmetric (deactivation might involve specific contributions of ToM regions to the human search for reciprocity. Consequently, the intensity of emotion attached to human reciprocity was represented in the amygdala, whereas insight into the reciprocity of others was reflected in activation across the reward-related and ToM regions. This suggests the critical role of mentalizing, which was not equated with reward expectation during

  15. Acoustic reciprocity: An extension to spherical harmonics domain.

    Science.gov (United States)

    Samarasinghe, Prasanga; Abhayapala, Thushara D; Kellermann, Walter

    2017-10-01

    Acoustic reciprocity is a fundamental property of acoustic wavefields that is commonly used to simplify the measurement process of many practical applications. Traditionally, the reciprocity theorem is defined between a monopole point source and a point receiver. Intuitively, it must apply to more complex transducers than monopoles. In this paper, the authors formulate the acoustic reciprocity theory in the spherical harmonics domain for directional sources and directional receivers with higher order directivity patterns.

  16. Neural correlate of human reciprocity in social interactions.

    Science.gov (United States)

    Sakaiya, Shiro; Shiraito, Yuki; Kato, Junko; Ide, Hiroko; Okada, Kensuke; Takano, Kouji; Kansaku, Kenji

    2013-01-01

    Reciprocity plays a key role maintaining cooperation in society. However, little is known about the neural process that underpins human reciprocity during social interactions. Our neuroimaging study manipulated partner identity (computer, human) and strategy (random, tit-for-tat) in repeated prisoner's dilemma games and investigated the neural correlate of reciprocal interaction with humans. Reciprocal cooperation with humans but exploitation of computers by defection was associated with activation in the left amygdala. Amygdala activation was also positively and negatively correlated with a preference change for human partners following tit-for-tat and random strategies, respectively. The correlated activation represented the intensity of positive feeling toward reciprocal and negative feeling toward non-reciprocal partners, and so reflected reciprocity in social interaction. Reciprocity in social interaction, however, might plausibly be misinterpreted and so we also examined the neural coding of insight into the reciprocity of partners. Those with and without insight revealed differential brain activation across the reward-related circuitry (i.e., the right middle dorsolateral prefrontal cortex and dorsal caudate) and theory of mind (ToM) regions [i.e., ventromedial prefrontal cortex (VMPFC) and precuneus]. Among differential activations, activation in the precuneus, which accompanied deactivation of the VMPFC, was specific to those without insight into human partners who were engaged in a tit-for-tat strategy. This asymmetric (de)activation might involve specific contributions of ToM regions to the human search for reciprocity. Consequently, the intensity of emotion attached to human reciprocity was represented in the amygdala, whereas insight into the reciprocity of others was reflected in activation across the reward-related and ToM regions. This suggests the critical role of mentalizing, which was not equated with reward expectation during social interactions.

  17. [Workplace Health Promotion in Small, Medium-Sized and Large Enterprises of the Health-Care Sector - Frequency, Reasons for the Company Management to Take Action and Barriers to Implementation].

    Science.gov (United States)

    Schaefer, E; Drexler, H; Kiesel, J

    2016-03-01

    The aim of this study was to gain insight into worksite health promotion in small and medium-sized companies compared to large concerns in Middle Franconia. Action in worksite health promotion, obstacles and demand for networks for workplace health promotion were determined. A standardised telephone interview served for collecting data for this cross-sectional study. The interviewee was always the manager or their proxy. 106 companies were contacted. The results of this study were analysed via qualitative and quantitative methods in SPSS(®) 20. It was possible to reach and interview 80 companies, a return rate of 75.5%. More than half the companies (68.8%) implemented at least one activity for worksite health promotion, especially ergonomic measures and measures to promote physical activity. Taking the size of the company into consideration when analysing the results, previous study results are confirmed. With an increasing size of the company, the relative frequency of measures for workplace health promotion rises. The motivation for worksite health promotion ranges from keeping the employees healthy (38.2%) to worksite health promotion as part of the business culture (9.1%). 81.1% of the companies consider their activity in worksite health promotion to be successful. Furthermore, 80.0% of the firms that implemented worksite health promotion were supported by a partner like a health insurance (43.2%). Those companies that did not implement any activities for worksite health promotion, state as a prime reason that they did not think about it as yet (44.0%). Besides, 44.0% of the companies without any worksite health promotion would like to implement measures. 65.5% of the companies that already took action in worksite health promotion and 56.0% of the companies that did not would like to cooperate with other firms in a network for workplace health promotion. Mutual exchange is the most important factor for them. The results of this study show that almost half of

  18. Reciprocity, spatial mapping and time reversal in electromagnetics

    CERN Document Server

    Altman, C

    2011-01-01

    This long awaited second edition traces the original developments from the 1970s and brings them up to date with new and previously unpublished material to give this work a new lease of life for the early twenty-first century and readers new to the topic. In the winter of 1970-71, Colman Altman had been finding almost exact symmetries in the computed reflection and transmission matrices for plane-stratified magnetoplasmas when symmetrically related directions of incidence were compared. At the suggestion of Kurt Suchy the complex conjugate wave fields, used to construct the eigenmode amplitudes via the mean Poynting flux densities, were replaced by the adjoint wave fields that would propagate in a medium with transposed constitutive tensors, to yield a scattering theorem – reciprocity in k-space -- in the computer output. To prove the result analytically, one had to investigate the properties of the adjoint Maxwell system, and the two independent proofs that followed, in 1975 and 1979, proceeded according t...

  19. Alternative energy efficient membrane bioreactor using reciprocating submerged membrane.

    Science.gov (United States)

    Ho, J; Smith, S; Roh, H K

    2014-01-01

    A novel membrane bioreactor (MBR) pilot system, using membrane reciprocation instead of air scouring, was operated at constant high flux and daily fluctuating flux to demonstrate its application under peak and diurnal flow conditions. Low and stable transmembrane pressure was achieved at 40 l/m(2)/h (LMH) by use of repetitive membrane reciprocation. The results reveal that the inertial forces acting on the membrane fibers effectively propel foulants from the membrane surface. Reciprocation of the hollow fiber membrane is beneficial for the constant removal of solids that may build up on the membrane surface and inside the membrane bundle. The membrane reciprocation in the reciprocating MBR pilot consumed less energy than coarse air scouring used in conventional MBR systems. Specific energy consumption for the membrane reciprocation was 0.072 kWh/m(3) permeate produced at 40 LMH flux, which is 75% less than for a conventional air scouring system as reported in literature without consideration of energy consumption for biological aeration (0.29 kWh/m(3)). The daily fluctuating flux test confirmed that the membrane reciprocation is effective to handle fluctuating flux up to 50 LMH. The pilot-scale reciprocating MBR system successfully demonstrated that fouling can be controlled via 0.43 Hz membrane reciprocation with 44 mm or higher amplitude.

  20. Advanced Natural Gas Reciprocating Engines(s)

    Energy Technology Data Exchange (ETDEWEB)

    Zurlo, James [Dresser, Inc., Addison, TX (United States)

    2012-04-05

    The ARES program was initiated in 2001 to improve the overall brake thermal efficiency of stationary, natural gas, reciprocating engines. The ARES program is a joint award that is shared by Dresser, Inc., Caterpillar and Cummins. The ARES program was divided into three phases; ARES I (achieve 44% BTE), ARES II (achieve 47% BTE) and ARES III (achieve 50% BTE). Dresser, Inc. completed ARES I in March 2005 which resulted in the commercialization of the APG1000 product line. ARES II activities were completed in September 2010 and the technology developed is currently being integrated into products. ARES III activities began in October 2010. The ARES program goal is to improve the efficiency of natural gas reciprocating engines. The ARES project is structured in three phases with higher efficiency goals in each phase. The ARES objectives are as follows: 1. Achieve 44% (ARES I), 47% (ARES II), and 50% brake thermal efficiency (BTE) as a final ARES III objective 2. Achieve 0.1 g/bhp-hr NOx emissions (with after-treatment) 3. Reduce the cost of the produced electricity by 10% 4. Improve or maintain reliability, durability and maintenance costs

  1. Reciprocal C-13-labeling: A method for investigating the catabolism of cosubstrates

    DEFF Research Database (Denmark)

    Christensen, B.; Nielsen, Jette

    2002-01-01

    The principle of reciprocal labeling is to use a uniformly C-13-labeled substrate as the primary carbon source and a naturally labeled cosubstrate. Metabolites derived from a naturally labeled cosubstrate, in this case amino acids, can then be identified by their relatively lower content of C-13...... as the uniformly labeled primary carbon source......., and information on the degradation pathway can be deduced. The technique is based on GC-MS measurements of amino acid labeling patterns, making the technique well suited for investigating the relative importance of amino acid biosynthesis and amino acid uptake from the medium, as the 13C content of the amino...

  2. Improving Mathematical Communication Ability and Self Regulation Learning of Yunior High Students by Using Reciprocal Teaching

    OpenAIRE

    Qohar, Abdul; Sumarmo, Utari

    2013-01-01

    This paper presents the findings from a posttest experiment control group design  by  using reciprocal teaching, conducted  in Indonesia University of Education to investigate students’ ability in mathematical communication and self regulated learning.  Subject of the study were 254 of 9th grade students from three junior high schools of high, medium, and low level in Bojonegoro, East Java.  The instruments of the study were an essay mathematical communication test, and a self regulated learn...

  3. Improving Mathematical Communication Ability and Self Regulation Learning Of Yunior High Students by Using Reciprocal Teaching

    Directory of Open Access Journals (Sweden)

    Abdul Qohar

    2013-01-01

    Full Text Available This paper presents the findings from a posttest experiment control group design  by  using reciprocal teaching, conducted  in Indonesia University of Education to investigate students’ ability in mathematical communication and self regulated learning.  Subject of the study were 254 of 9th grade students from three junior high schools of high, medium, and low level in Bojonegoro, East Java.  The instruments of the study were an essay mathematical communication test, and a self regulated learning scale. The study found that reciprocal teaching took the best role among school  cluster  and students’ prior mathematics ability on students’ mathematical communication ability and self regulated learning as well.  The other finding were there was interaction between school cluster and teaching approaches, but was no interaction between students’ prior mathematics ability and teaching approaches on mathematical communication ability and  self regulated learning. Moreover, there was association between mathematical communication and self regulated learningKeywords: Reciprocal Teaching, Mathematical Communication, Self Regulated Learning DOI: http://dx.doi.org/10.22342/jme.4.1.562.59-74

  4. Isozyme expression of Chinese and Japanese populations of Chlamys farreri and their reciprocal hybrids

    Science.gov (United States)

    Li, Taiwu; Liu, Yan; Song, Linsheng; Sun, Xiuqin

    2005-06-01

    Chinese and Japanese population of Chlamys farreri and their reciprocal hybrids were surveyed in isozyme variability at 13 loci by polyacrytamide gel electrophoresis (PAGE). Isozyme banding patterns indicated these hybrids were diploid. Loci that were observed as being monomorphic in inbred populations of C. farreri were also found to be monomorphic in filial progeny; loci that observed to be polymorphic in parental type generations were also polymorphic in hybrid generations. Differences existed among allelic frequency of the four types of cross. Within the reciprocal hybrids the expression of malic enzyme (ME) isozyme was sufficient to distinguishing individual hybrids because of the band, Rf=0.38. However, there were no noticeable variations among all the samples to differentiate one from another. Inbreeding was likely to be the main problem in aquaculture. The introduction of new broodstock can improve the genetic diversity. Hybrid vigor has manifested to a certain extent in the present study.

  5. The frequency of clinical pregnancy and implantation rate after cultivation of embryos in a medium with granulocyte macrophage colony-stimulating factor (GM-CSF) in patients with preceding failed attempts of ART.

    Science.gov (United States)

    Tevkin, S; Lokshin, V; Shishimorova, M; Polumiskov, V

    2014-10-01

    The application in IVF practice of modern techniques can improve positive outcome of each cycle in the assisted reproductive technology (ART) programs and the effectiveness of treatment as a whole. There are embryos in the female reproductive tract in physiological medium which contain various cytokines and growth factors. It plays an important role in the regulation of normal embryonic development, improve implantation and subsequently optimizing the development of the fetus and the placenta. Granulocyte macrophage colony-stimulating factor (GM-CSF is one of the cytokines playing an important role in reproductive function. Addition of recombinant GM-CSF to the culture medium can makes closer human embryos culture to in vivo conditions and improve the efficacy ART cycles. The analysis of culture embryos in EmbryoGen medium has shown that fertilization rate embryo culture and transfer to patients with previous unsuccessful attempts increases clinical pregnancy rate compared to the control group 39.1 versus 27.8%, respectively. It is noted that the implantation rate (on 7 weeks' gestation) and progressive clinical pregnancy rate (on 12 weeks' gestation) were significantly higher in group embryos culture in EmbryoGen medium compared to standard combination of medium (ISM1+VA), and were 20.4 and 17.4% versus 11.6 and 9.1%, respectively.

  6. Static And Kinematic Formulation Of Planar Reciprocal Assemblies

    DEFF Research Database (Denmark)

    Parigi, Dario; Kirkegaard, Poul Henning

    2013-01-01

    Planar reciprocal frames are two dimensional structures formed by elements joined together according to the principle of structural reciprocity. In this paper a rigorous formulation of the static and kinematic problem is proposed and developed by extending the work on pin-jointed assemblies...

  7. Apical extrusion of debris using reciprocating files and rotary ...

    African Journals Online (AJOL)

    Procedure: Sixty extracted human mandibular premolars were used. The root canals were instrumented using reciprocating (WaveOne, Reciproc, SafeSider) or rotary ... and cross‑sections, and kinematics, and this situation may influence the amount of apically extruded debris through the apical foramen.[15]. The aim of this ...

  8. Static and kinematic formulation of planar reciprocal assemblies

    DEFF Research Database (Denmark)

    Parigi, Dario; Sassone, Mario; Kirkegaard, Poul Henning

    2014-01-01

    Planar reciprocal frames are two dimensional structures formed by elements joined together according to the principle of structural reciprocity. In this paper a rigorous formulation of the static and kinematic problem is proposed and developed extending the theory of pin-jointed assemblies...

  9. Design and Fabrication of a Free-Form Reciprocal Roof

    DEFF Research Database (Denmark)

    Parigi, Dario

    2015-01-01

    of relations between design parameters and a wide array of measurable performances. Due to the reciprocal structures geometric complexity, the shape generation process is handled using the Reciprocalizer, a software tool developed by the author that embeds in a computational environment the constructional...

  10. Strong reciprocity is not uncommon in the "wild".

    Science.gov (United States)

    Runciman, W G

    2012-02-01

    Guala is right to draw attention to the difficulty of extrapolating from the experimental evidence for weak or strong reciprocity to what is observed in the "wild." However, there may be more strong reciprocity in real-world communities than he allows for, as strikingly illustrated in the example of the Mafia.

  11. Sex differences in the reciprocal behaviour of children with autism

    NARCIS (Netherlands)

    Backer van Ommeren, Tineke; Koot, Hans M; Scheeren, Anke M; Begeer, Sander

    2017-01-01

    Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with

  12. Reciprocity, social ties, and competition in markets for experience goods

    DEFF Research Database (Denmark)

    Huck, Steffen; Tyran, Jean-Robert

    2007-01-01

    Reciprocal customers may disproportionately improve the performance of markets for experience goods. Reciprocal customers reward (punish) firms for providing good (bad) quality by upholding (terminating) the customer relation. This may induce firms to provide good quality which, in turn, may induce...

  13. Reciprocity in International Affairs: An Analysis of Nigeria/South ...

    African Journals Online (AJOL)

    DrNneka

    2012-03-07

    Mar 7, 2012 ... It argued that the principle of reciprocity in international relations came to the fore in the row. The paper made the point ... Key Words: Reciprocity, International, Affairs, Diplomatic face-off, Nigeria, South. Africa. Introduction. In an increasingly ...... Public Law 3 (1), 105 – 111. Emewu, I. (2012). Nigeria, South ...

  14. Intention-based reciprocity and the hidden costs of control

    NARCIS (Netherlands)

    von Siemens, F.

    2011-01-01

    Empirical research suggests that - rather than improving incentives - exerting control can reduce workers' performance by eroding motivation. The present paper shows that intention-based reciprocity can cause such motivational crowding-out if individuals differ in their propensity for reciprocity

  15. Sex differences in the reciprocal behaviour of children with autism

    NARCIS (Netherlands)

    Backer van Ommeren, Tineke; Koot, Hans M; Scheeren, Anke M; Begeer, Sander

    2016-01-01

    Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with

  16. Sex Differences in the Reciprocal Behaviour of Children with Autism

    Science.gov (United States)

    Backer van Ommeren, Tineke; Koot, Hans M.; Scheeren, Anke M.; Begeer, Sander

    2017-01-01

    Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with autism spectrum disorder (32 girls, 114 boys) and in…

  17. Instructional Guidance in Reciprocal Peer Tutoring With Task Cards

    Science.gov (United States)

    Iserbyt, Peter; Elen, Jan; Behets, Daniel

    2010-01-01

    This article addresses the issue of instructional guidance in reciprocal peer tutoring with task cards as learning tools. Eighty-six Kinesiology students (age 17-19 years) were randomized across four reciprocal peer tutoring settings, differing in quality and quantity of guidance, to learn Basic Life Support (BLS) with task cards. The separate and…

  18. Reciprocal Relationships between Math Self-Concept and Math Anxiety

    Science.gov (United States)

    Ahmed, Wondimu; Minnaert, Alexander; Kuyper, Hans; van der Werf, Greetje

    2012-01-01

    The present study examined the reciprocal relationships between self-concept and anxiety in mathematics. A sample of 495 grade 7 students (51% girls) completed self-report measures assessing self-concept and anxiety three times in a school year. Structural equation modeling was used to test a cross-lagged panel model of reciprocal effects between…

  19. Reciprocal Pronouns Binding within Psych-Verb Constructions

    Science.gov (United States)

    Epoge, Napoleon

    2015-01-01

    This paper aims at giving an analysis of certain syntactic peculiarities of reciprocal pronouns within verbs of psychological state, commonly known as psych-verbs. The analysis reveal that psych-verbs constructions have a peculiar property in that the binding conditions of reciprocal pronouns are satisfied in Experiencer-Subject (ES) psychverbs…

  20. Thermal Powered Reciprocating-Force Motor

    Science.gov (United States)

    Tatum, III, Paul F. (Inventor); McDow Elliott, Amelia (Inventor)

    2015-01-01

    A thermal-powered reciprocating-force motor includes a shutter switchable between a first position that passes solar energy and a second position that blocks solar energy. A shape memory alloy (SMA) actuator is coupled to the shutter to control switching thereof between the shutter's first and second position. The actuator is positioned with respect to the shutter such that (1) solar energy impinges on the SMA when the shutter is in its first position so that the SMA experiences contraction in length until the shutter is switched to its second position, and (2) solar energy is impeded from impingement on the SMA when the shutter is in its second position so that the SMA experiences extension in length. Elastic members coupled to the actuator apply a force to the SMA that aids in its extension in length until the shutter is switched to its first position.

  1. Comprehensive model of a hermetic reciprocating compressor

    Science.gov (United States)

    Yang, B.; Ziviani, D.; Groll, E. A.

    2017-08-01

    A comprehensive simulation model is presented to predict the performance of a hermetic reciprocating compressor and to reveal the underlying mechanisms when the compressor is running. The presented model is composed of sub-models simulating the in-cylinder compression process, piston ring/journal bearing frictional power loss, single phase induction motor and the overall compressor energy balance among different compressor components. The valve model, leakage through piston ring model and in-cylinder heat transfer model are also incorporated into the in-cylinder compression process model. A numerical algorithm solving the model is introduced. The predicted results of the compressor mass flow rate and input power consumption are compared to the published compressor map values. Future work will focus on detailed experimental validation of the model and parametric studies investigating the effects of structural parameters, including the stroke-to-bore ratio, on the compressor performance.

  2. Retrofitting reciprocating compressors for noise control

    International Nuclear Information System (INIS)

    Frank, L.; Qualfe, R.

    1992-01-01

    The Alberta Energy Resources Conservation Board recently enacted their noise control directive ID 88-1. The effects of this regulation on the operation of an oil and gas facility are discussed, and a specific case history is presented to provide a disciplined strategy for noise attenuation retrofits. An investigation was carried out into sound sources at a reciprocating compressor gas plant, revealing several sound sources: engine exhaust stacks, engine exhaust silencer shells, direct-drive fan cooler inlets, direct drive fan cooler outlets, aerial cooler inlets and aerial cooler outlets. Details are presented of the investigative techniques and order-ranking of sources by decibel level. When controlling engine exhaust noise, silencers or mufflers are the preferred treatment. Choice of type (reactive or absorptive) and specification of acoustical performance of a silencer are discussed. The gas plant achieved noise reductions of 6-13 dB, measured at affected residences, through the use of engine exhaust silencers. 4 figs., 2 tabs

  3. Sleep and exercise: a reciprocal issue?

    Science.gov (United States)

    Chennaoui, Mounir; Arnal, Pierrick J; Sauvet, Fabien; Léger, Damien

    2015-04-01

    Sleep and exercise influence each other through complex, bilateral interactions that involve multiple physiological and psychological pathways. Physical activity is usually considered as beneficial in aiding sleep although this link may be subject to multiple moderating factors such as sex, age, fitness level, sleep quality and the characteristics of the exercise (intensity, duration, time of day, environment). It is therefore vital to improve knowledge in fundamental physiology in order to understand the benefits of exercise on the quantity and quality of sleep in healthy subjects and patients. Conversely, sleep disturbances could also impair a person's cognitive performance or their capacity for exercise and increase the risk of exercise-induced injuries either during extreme and/or prolonged exercise or during team sports. This review aims to describe the reciprocal fundamental physiological effects linking sleep and exercise in order to improve the pertinent use of exercise in sleep medicine and prevent sleep disorders in sportsmen. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Sex differences in the reciprocal behaviour of children with autism.

    Science.gov (United States)

    Backer van Ommeren, Tineke; Koot, Hans M; Scheeren, Anke M; Begeer, Sander

    2017-08-01

    Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with autism spectrum disorder (32 girls, 114 boys) and in typically developing children (24 girls, 55 boys). While children with autism spectrum disorder showed clear limitations in reciprocal behaviour compared to typically developing children, sex differences were found only in the autism spectrum disorder group: girls with autism spectrum disorder had higher reciprocity scores than boys with autism spectrum disorder. However, compared to typically developing girls, girls with autism spectrum disorder showed subtle differences in reciprocal behaviour. The sex-specific response patterns in autism spectrum disorder can inform and improve the diagnostic assessment of autism in females.

  5. High-Resolution Reciprocal Space Mapping for Characterizing Deformation Structures

    DEFF Research Database (Denmark)

    Pantleon, Wolfgang; Wejdemann, Christian; Jakobsen, Bo

    2014-01-01

    With high-angular resolution three-dimensional X-ray diffraction (3DXRD), quantitative information is gained about dislocation structures in individual grains in the bulk of a macroscopic specimen by acquiring reciprocal space maps. In high-resolution 3D reciprocal space maps of tensile-deformed ......With high-angular resolution three-dimensional X-ray diffraction (3DXRD), quantitative information is gained about dislocation structures in individual grains in the bulk of a macroscopic specimen by acquiring reciprocal space maps. In high-resolution 3D reciprocal space maps of tensile...... dynamics is followed in situ during varying loading conditions by reciprocal space mapping: during uninterrupted tensile deformation, formation of subgrains is observed concurrently with broadening of Bragg reflections shortly after the onset of plastic deformation. When the traction is terminated, stress...

  6. 76 FR 12923 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2011-03-09

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines... pollutants for existing stationary spark ignition reciprocating internal combustion engines. The final rule... reciprocating internal combustion generation, engine. transmission, or distribution. 622110 Medical and surgical...

  7. Non-reciprocal wave propagation in one-dimensional nonlinear periodic structures

    Directory of Open Access Journals (Sweden)

    Benbiao Luo

    2018-01-01

    Full Text Available We study a one-dimensional nonlinear periodic structure which contains two different spring stiffness and an identical mass in each period. The linear dispersion relationship we obtain indicates that our periodic structure has obvious advantages compared to other kinds of periodic structures (i.e. those with the same spring stiffness but two different mass, including its increased flexibility for manipulating the band gap. Theoretically, the optical cutoff frequency remains unchanged while the acoustic cutoff frequency shifts to a lower or higher frequency. A numerical simulation verifies the dispersion relationship and the effect of the amplitude-dependent signal filter. Based upon this, we design a device which contains both a linear periodic structure and a nonlinear periodic structure. When incident waves with the same, large amplitude pass through it from opposite directions, the output amplitude of the forward input is one order magnitude larger than that of the reverse input. Our devised, non-reciprocal device can potentially act as an acoustic diode (AD without an electrical circuit and frequency shifting. Our result represents a significant step forwards in the research of non-reciprocal wave manipulation.

  8. Trust and reciprocity: are effort and money equivalent?

    Directory of Open Access Journals (Sweden)

    Iris Vilares

    2011-02-01

    Full Text Available Trust and reciprocity facilitate cooperation and are relevant to virtually all human interactions. They are typically studied using trust games: one subject gives (entrusts money to another subject, which may return some of the proceeds (reciprocate. Currently, however, it is unclear whether trust and reciprocity in monetary transactions are similar in other settings, such as physical effort. Trust and reciprocity of physical effort are important as many everyday decisions imply an exchange of physical effort, and such exchange is central to labor relations. Here we studied a trust game based on physical effort and compared the results with those of a computationally equivalent monetary trust game. We found no significant difference between effort and money conditions in both the amount trusted and the quantity reciprocated. Moreover, there is a high positive correlation in subjects' behavior across conditions. This suggests that trust and reciprocity may be character traits: subjects that are trustful/trustworthy in monetary settings behave similarly during exchanges of physical effort. Our results validate the use of trust games to study exchanges in physical effort and to characterize inter-subject differences in trust and reciprocity, and also suggest a new behavioral paradigm to study these differences.

  9. Trust and reciprocity: are effort and money equivalent?

    Science.gov (United States)

    Vilares, Iris; Dam, Gregory; Kording, Konrad

    2011-02-25

    Trust and reciprocity facilitate cooperation and are relevant to virtually all human interactions. They are typically studied using trust games: one subject gives (entrusts) money to another subject, which may return some of the proceeds (reciprocate). Currently, however, it is unclear whether trust and reciprocity in monetary transactions are similar in other settings, such as physical effort. Trust and reciprocity of physical effort are important as many everyday decisions imply an exchange of physical effort, and such exchange is central to labor relations. Here we studied a trust game based on physical effort and compared the results with those of a computationally equivalent monetary trust game. We found no significant difference between effort and money conditions in both the amount trusted and the quantity reciprocated. Moreover, there is a high positive correlation in subjects' behavior across conditions. This suggests that trust and reciprocity may be character traits: subjects that are trustful/trustworthy in monetary settings behave similarly during exchanges of physical effort. Our results validate the use of trust games to study exchanges in physical effort and to characterize inter-subject differences in trust and reciprocity, and also suggest a new behavioral paradigm to study these differences.

  10. Clustering in large networks does not promote upstream reciprocity.

    Directory of Open Access Journals (Sweden)

    Naoki Masuda

    Full Text Available Upstream reciprocity (also called generalized reciprocity is a putative mechanism for cooperation in social dilemma situations with which players help others when they are helped by somebody else. It is a type of indirect reciprocity. Although upstream reciprocity is often observed in experiments, most theories suggest that it is operative only when players form short cycles such as triangles, implying a small population size, or when it is combined with other mechanisms that promote cooperation on their own. An expectation is that real social networks, which are known to be full of triangles and other short cycles, may accommodate upstream reciprocity. In this study, I extend the upstream reciprocity game proposed for a directed cycle by Boyd and Richerson to the case of general networks. The model is not evolutionary and concerns the conditions under which the unanimity of cooperative players is a Nash equilibrium. I show that an abundance of triangles or other short cycles in a network does little to promote upstream reciprocity. Cooperation is less likely for a larger population size even if triangles are abundant in the network. In addition, in contrast to the results for evolutionary social dilemma games on networks, scale-free networks lead to less cooperation than networks with a homogeneous degree distribution.

  11. ADVANCED RECIPROCATING COMPRESSION TECHNOLOGY (ARCT). FINAL REPORT

    International Nuclear Information System (INIS)

    Danny M. Deffenbaugh; Klaus Brun; Ralph E. Harris; J. Pete Harrell; Robert J. Mckee; J. Jeffrey Moore; Steven J. Svedeman; Anthony J. Smalley; Eugene L. Broerman; Robert A Hart; Marybeth G. Nored; Ryan S. Gernentz; Shane P. Siebenaler

    2005-01-01

    The U.S. natural gas pipeline industry is facing the twin challenges of increased flexibility and capacity expansion. To meet these challenges, the industry requires improved choices in gas compression to address new construction and enhancement of the currently installed infrastructure. The current fleet of installed reciprocating compression is primarily slow-speed integral machines. Most new reciprocating compression is and will be large, high-speed separable units. The major challenges with the fleet of slow-speed integral machines are: limited flexibility and a large range in performance. In an attempt to increase flexibility, many operators are choosing to single-act cylinders, which are causing reduced reliability and integrity. While the best performing units in the fleet exhibit thermal efficiencies between 90% and 92%, the low performers are running down to 50% with the mean at about 80%. The major cause for this large disparity is due to installation losses in the pulsation control system. In the better performers, the losses are about evenly split between installation losses and valve losses. The major challenges for high-speed machines are: cylinder nozzle pulsations, mechanical vibrations due to cylinder stretch, short valve life, and low thermal performance. To shift nozzle pulsation to higher orders, nozzles are shortened, and to dampen the amplitudes, orifices are added. The shortened nozzles result in mechanical coupling with the cylinder, thereby, causing increased vibration due to the cylinder stretch mode. Valve life is even shorter than for slow speeds and can be on the order of a few months. The thermal efficiency is 10% to 15% lower than slow-speed equipment with the best performance in the 75% to 80% range. The goal of this advanced reciprocating compression program is to develop the technology for both high speed and low speed compression that will expand unit flexibility, increase thermal efficiency, and increase reliability and integrity

  12. Generalized Gribov-Lipatov Reciprocity and AdS/CFT

    International Nuclear Information System (INIS)

    Beccaria, M.; Macorini, G.; Forini, V.

    2010-01-01

    Planar □=4 SYM theory and QCD share the gluon sector, suggesting the investigation of Gribov-Lipatov reciprocity in the supersymmetric theory. Since the AdS/CFT correspondence links □=4 SYM and superstring dynamics on AdS 5 x S5, reciprocity is also expected to show up in the quantum corrected energies of certain classical string configurations dual to gauge theory twist-operators. We review recent results confirming this picture and revisiting the old idea of Gribov-Lipatov reciprocity as a modern theoretical tool useful for the study of open problems in AdS/CFT.

  13. Verifying of reciprocal relations for nonlinear quadripole in unsteady mode

    Science.gov (United States)

    Bardin, Alexey; Ignatjev, Vyacheslav; Orlov, Andrey; Perchenko, Sergey

    This paper deals with experimental verification of reciprocal relations of nonlinear quadripole for unsteady mode in external magnetic field. We find out transients of measured voltages in the quadripole after current switch. These transients are caused by changing of current-voltage characteristics (CVC) of quadripole. We propose the reciprocal relations for linear part of full resistance matrix and its experimental verification method based on algorithm of separation of resistance matrix linear part. It is shown that the proposed reciprocal relations are valid with 10-3 relatively accuracy even for non-stationary case in external magnetic field.

  14. Preliminarily measurement and analysis of sawing forces in fresh cadaver mandible using reciprocating saw for reality-based haptic feedback.

    Science.gov (United States)

    Yua, Dedong; Zhengb, Xiaohu; Chenc, Ming; Shend, Steve G F

    2012-05-01

    The aim of the study was to preliminarily measure and analyze the cutting forces in fresh Chinese cadaver mandible using a clinically widely used reciprocating saw for reality-based haptic feedback. Eight mandibles were taken from fresh Chinese cadavers, 4 females and 4 males, aged between 59 and 95 years. A set of sawing experiments, using a surgery Stryker micro-reciprocating saw and Kistler piezoelectric dynamometer, was carried out by a CNC machining center. Under different vibration frequencies of saw and feeding rates measured from orthognathic surgery, sawing forces were recorded by a signal acquisition system. Remarkably different sawing forces were measured from different cadavers. Feed and vibration frequency of the reciprocating saw could determine the cutting forces only on 1 body. To reduce the impact of bone thickness changes on the cutting force measurements, all the cutting force data should be converted to the force of unit cutting length. The vibration frequency of haptic feedback system is determined by main cutting forces. Fast Fourier transform method can be used to calculate the frequency of this system. To simulate surgery in higher fidelity, all the sawing forces from the experiment should be amended by experienced surgeons before use in virtual reality surgery simulator. Sawing force signals of different ages for force feedback were measured successfully, and more factors related to the bone mechanical properties, such as bone density, should be concerned in the future.

  15. Focal plane scanner with reciprocating spatial window

    Science.gov (United States)

    Mao, Chengye (Inventor)

    2000-01-01

    A focal plane scanner having a front objective lens, a spatial window for selectively passing a portion of the image therethrough, and a CCD array for receiving the passed portion of the image. All embodiments have a common feature whereby the spatial window and CCD array are mounted for simultaneous relative reciprocating movement with respect to the front objective lens, and the spatial window is mounted within the focal plane of the front objective. In a first embodiment, the spatial window is a slit and the CCD array is one-dimensional, and successive rows of the image in the focal plane of the front objective lens are passed to the CCD array by an image relay lens interposed between the slit and the CCD array. In a second embodiment, the spatial window is a slit, the CCD array is two-dimensional, and a prism-grating-prism optical spectrometer is interposed between the slit and the CCD array so as to cause the scanned row to be split into a plurality of spectral separations onto the CCD array. In a third embodiment, the CCD array is two-dimensional and the spatial window is a rectangular linear variable filter (LVF) window, so as to cause the scanned rows impinging on the LVF to be bandpass filtered into spectral components onto the CCD array through an image relay lens interposed between the LVF and the CCD array.

  16. Monitoring fuel consumption for reciprocating engines

    International Nuclear Information System (INIS)

    Zebelean, D.C.

    1991-01-01

    This paper reports that Northwest Pipeline Corp. has experienced substantial fuel cost savings through a program that provides continuous monitoring of predicted consumption against actual usage for reciprocating engines. With the continuous monitoring program, the company can gauge specific fuel consumption, flag inefficient engines and determine possible problems with computer software or hardware used to measure engine operations. The plan was initiated as part of an overall effort to reduce pipe line operating cost to remain market competitive by reducing cost of services to the customer. One of the factors in determining Northwest Pipeline's cost of service is the cost of fueling engines to transport natural gas. In 1990, Northwest consumed approximately 9,600,000 MMBtu in engine fuel. Fuel gas always has been accounted for and measured. However, the thermal efficiency of the fuel gas consumed was never quantified. Engineering management set a goal in 1989 to audit fuel consumption monthly on the basis of actual fuel consumed compared to the manufacturer's predicted consumption curves. The fuel consumption comparison between actual consumption with manufacturer's predicted consumption decreased 4% in six months after the first report was published. Unbalanced engines, faulty spark plugs, fuel valves, engines requiring overhauls, and even computer software and hardware problems were found, based on this report. Total decrease in the comparison of 4% was not all realized. Approximately 1.5% of the decrease was due to revising the manufacturer's fuel consumption curves to correctly predict Northwest's vintage of engine

  17. Improving reading comprehension through Reciprocal Teaching Method

    Directory of Open Access Journals (Sweden)

    Endang Komariah

    2015-10-01

    Full Text Available This study is aimed at discovering the benefits of the Reciprocal Teaching Method (RTM in the reading classroom, finding out the achievements of students after four comprehension training sessions of using RTM, and exploring the perceptions of students on the use of RTM. This method uses four comprehension strategies: predicting, questioning, clarifying, and summarizing, to help learners monitor their development of reading comprehension by themselves. Students work in groups of four or five and the members are divided into five roles which are the leader, predictor, clarifier, questioner, and summarizer. The subjects were 24 students from the twelfth grade at a high school in Banda Aceh. Observations, tests, documents and interviews were collected to get the data. The results showed that the students were more active and productive in the reading classroom after RTM sessions and their reading proficiency improved. They learnt how to apply several of the strategies from RTM while reading. The results also showed that they preferred this method for teaching-learning reading compared to the conventional one. Therefore, teachers are suggested to consider using this method for teaching reading that instils the students on how to apply the four comprehension strategies used in reading.

  18. Ping-Pong Beam Training for Reciprocal Channels with Delay Spread

    DEFF Research Database (Denmark)

    Carvalho, Elisabeth De; Andersen, Jørgen Bach

    2015-01-01

    We present an iterative beam training procedure for a reciprocal channel with delay spread between two massive antenna arrays. The primary application is communication at millimeter wave frequencies. The procedure is based on ping pong transmissions. For each matricial channel coefficient......, it tracks the left and right singular vectors associated to the maximal singular value. Based on the set of singular vectors, we build transmit and receive equalizers. A simple equalization based on matched filtering is showed to be optimal in the case of a Gaussian i.i.d. channel and a sparse channel....

  19. Free-field reciprocity calibration of laboratory standard (LS) microphones using a time selective technique

    DEFF Research Database (Denmark)

    Rasmussen, Knud; Barrera Figueroa, Salvador

    2006-01-01

    Although the basic principle of reciprocity calibration of microphones in a free field is simple, the practical problems are complicated due to the low signal-to-noise ratio and the influence of cross talk and reflections from the surroundings. The influence of uncorrelated noise can be reduced...... by conventional narrow-band filtering and time averaging, while correlated signals like cross talk and reflections can be eliminated by using time-selective postprocessing techniques. The technique used at DPLA overcomes both these problems using a B&K Pulse analyzer in the SSR mode (steady state response......) and an FFT-based time-selective technique. The complex electrical transfer impedance is measured in linear frequency steps from a few kHz to about three times the resonance frequency of the microphones. The missing values at low frequencies are estimated from a detailed knowledge of the pressure...

  20. Non-reciprocal optical mirrors based on spatio-temporal acousto-optic modulation

    Science.gov (United States)

    Fleury, R.; Sounas, D. L.; Alù, A.

    2018-03-01

    Here, we investigate a scheme to realize free-space isolators and highly non-reciprocal mirrors with weak modulation imparted by an acoustic wave. We propose a strategy to dramatically break time-reversal symmetry by exploiting resonant interactions between a travelling acoustic wave and highly resonant Fabry-Pérot modes, inducing total reflection of an optical beam at a given angle, and no reflection at the negative angle. Different from conventional acousto-optic isolators, which are based on non-resonant frequency conversion and filtering, our proposal operates at the frequency of the optical signal by tailoring the resonant properties of the structure as well as the acoustic wave frequency and intensity, enabling 50 dB isolation with modest modulation requirements. Operation in the reflection mode allows for close-to-zero insertion loss, enabling disruptive opportunities in our ability to control and manipulate photons.

  1. Reciprocal Rights and Responsibilities in Parent-Child Relations

    Science.gov (United States)

    Baumrind, Diana

    1978-01-01

    This article examines critically the case for protecting children's rights as against the case for protecting children's welfare. The principle of reciprocity in parent-child relations is rejected. (Author/AM)

  2. Research on networked manufacturing system for reciprocating pump industry

    Science.gov (United States)

    Wu, Yangdong; Qi, Guoning; Xie, Qingsheng; Lu, Yujun

    2005-12-01

    Networked manufacturing is a trend of reciprocating pump industry. According to the enterprises' requirement, the architecture of networked manufacturing system for reciprocating pump industry was proposed, which composed of infrastructure layer, system management layer, application service layer and user layer. Its main functions included product data management, ASP service, business management, and customer relationship management, its physics framework was a multi-tier internet-based model; the concept of ASP service integration was put forward and its process model was also established. As a result, a networked manufacturing system aimed at the characteristics of reciprocating pump industry was built. By implementing this system, reciprocating pump industry can obtain a new way to fully utilize their own resources and enhance the capabilities to respond to the global market quickly.

  3. Comparison of the Effect of Dual-Axis Rotational Coronary Angiography Versus Conventional Coronary Angiography on Frequency of Acute Kidney Injury, X-Ray Exposure Time, and Quantity of Contrast Medium Injected.

    Science.gov (United States)

    Di Serafino, Luigi; Turturo, Maurizio; Lanzone, Saverio; Marano, Melissa; Scognamiglio, Gabriella; Trimarco, Bruno; Cirillo, Plinio; Esposito, Giovanni; D'Agostino, Carlo

    2018-02-07

    Dual-axis rotational coronary angiography (DARCA) has already been shown to reduce both the amount of contrast medium and radiation exposure compared with conventional coronary angiography (CCA). However, a clinical benefit of such imaging modality has never been demonstrated. The aim of this study was to evaluate the efficacy of DARCA to prevent acute kidney injury (AKI) compared with CCA. Consecutive patients who underwent coronary angiography were enrolled to DARCA (n = 80) or CCA (n = 80). Patients presenting with ST-segment elevation myocardial infarction or previously underwent coronary artery bypass graft were excluded. The 2 groups were homogeneous in terms of both clinical and procedural characteristics. Total x-ray time and total amount of contrast medium were significantly lower in the DARCA group compared with the CCA group (x-ray time 3.2 minutes [1.8 to 7.0] vs 5.1 minutes [2.6 to 9.9], p = 0.002; contrast medium amount 40 ml [31 to 116] vs 80 ml [50 to 150], p <0.001). AKI more often occurred in the CCA group compared with the DARCA group (16 [20%] vs 4 [5%], p = 0.007). Moreover, in patients presenting with acute coronary syndrome (ACS) or who underwent percutaneous coronary intervention (PCI), AKI more often occurred in the CCA group compared with the DARCA group (ACS patients, 6 [29%] vs 2 [6%], p = 0.04, and PCI patients, 11 [33%] vs 0 [0%], p <0.001). In addition, in patients with high pretest probability of coronary artery disease, AKI more often occurred in the CCA group compared with the DARCA group (11 [55%] vs 2 [6%], p <0.001). In conclusion, DARCA significantly reduces both x-ray exposure and amount of contrast medium usage, thereby reducing the occurrence of AKI compared with CCA. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Reciprocality of Recombination Events That Rearrange the Chromosome

    OpenAIRE

    Mahan, M. J.; Roth, J. R.

    1988-01-01

    We describe a genetic system for studying the reciprocality of chromosomal recombination; all substrates and recombination functions involved are provided exclusively by the bacterial chromosome. The genetic system allows the recovery of both recombinant products from a single recombination event. The system was used to demonstrate the full reciprocality of three different types of recombination events: (1) intrachromosomal recombination between direct repeats, causing deletions; (2) intrachr...

  5. Deformation and fracture incidence of Reciproc instruments: a clinical evaluation.

    Science.gov (United States)

    Plotino, G; Grande, N M; Porciani, P F

    2015-02-01

    To investigate the incidence of fracture and deformation observed on Reciproc instruments after clinical use. A total of 1696 Reciproc NiTi instruments that were discarded after normal clinical usage over 30 months were collected. Of these 1580 instruments were R25 (93%), 76 were R40 (5%), and 40 were R50 (2%). The treatments included 3780 root canal preparations, 3023 primary treatments and 757 retreatments. Root canal preparation was standardized and followed the manufacturer's directions for the use of Reciproc files without creating prior glide path with hand instruments. In retreatment cases, Reciproc R25 instrument was used to remove all filling material and to complete the preparation. Each instrument was used for shaping only one tooth. All the instruments used were inspected under a microscope to detect signs of fracture or deformation and, if any fracture existed, the length of the files was measured. Data were analysed using a chi-square test with a level of significance set at P < .05. A total of 8 Reciproc R25 instruments fractured during treatment, which represents 0.47% of the number of instruments used and 0.21% of the root canals treated. Five instruments fractured in primary treatment cases and three instruments during retreatments. Six Reciproc R25 deformed during clinical use (0.35% of the number of instruments used and 0.15% of the root canals treated), four during retreatments and two during primary treatments. The deformation reported was unwinding of the blades, one at 1 mm from the tip and five between 2 and 3 mm from the tip. No deformations or fracture were registered for the Reciproc R40 and R50 instruments. Root canal instrumentation following the manufacturer's instructions can be performed with Reciproc instruments with a very low incidence of instrument fracture and deformation. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  6. Reciprocal cooperation in avian mobbing: playing nice pays.

    Science.gov (United States)

    Wheatcroft, David J; Price, Trevor D

    2008-08-01

    Unrelated passerine birds often join together while mobbing, a widespread antipredator behavior during which birds harass a predator. Although previous analyses concluded that mobbing could not have evolved via reciprocity, Krams and colleagues' field experiments show that birds preferentially join mobs with neighbors that have aided them previously, suggesting that these birds utilize reciprocity-based strategies involving individual recognition and recollection of previous interactions with others. This implies a level of sophistication in bird communities greater than had previously been realized.

  7. The general chain transform and self-reciprocal functions

    Directory of Open Access Journals (Sweden)

    Cyril Nasim

    1985-01-01

    Full Text Available A theory of a generalized form of the chain transforms of order n is developed, and various properties of these are established including the Parseval relation. Most known cases of the standard theory are derived as special cases. Also a theory of self-reciprocal functions is given, based on these general chain transforms; and relations among various classes of self-reciprocal functions are established.

  8. Efficient Design And Fabrication Of Free-Form Reciprocal Structures

    DEFF Research Database (Denmark)

    Parigi, Dario; Kirkegaard, Poul Henning

    2013-01-01

    Structures based on the principle of reciprocity have been autonomously studied and used since the antiquity on the basis of different needs and purposes. The application of the principle of reciprocity requires the presence of at least two elements, at the same time both supporting and being sup......-notched wooden sticks of 22mm of diameter; this paper describes the overall process from the design to the fabrication....

  9. Asymmetric reproductive isolation during simultaneous reciprocal mating in pulmonates.

    Science.gov (United States)

    Wiwegweaw, Amporn; Seki, Keiichi; Mori, Hiroshi; Asami, Takahiro

    2009-04-23

    The generality of asymmetric reproductive isolation between reciprocal crosses suggests that the evolution of isolation mechanisms often proceeds in reciprocal asymmetry. In hermaphroditic snails that copulate simultaneously and reciprocally, asymmetry in premating isolation may not be readily detectable because the failure of the symmetric performance of courtship would prevent copulation from occurring. On the other hand, through their prolonged copulation, snails discriminate among mates when exchanging spermatophores for their benefit and thus may exhibit asymmetric reproductive isolation during interspecific mating. However, no clear case of reciprocal asymmetry has been found in reproductive isolation between snail species. Here we show a discrete difference in hybridization success between simultaneous reciprocal copulations between two species of pulmonate snails. Premating isolation of Bradybaena pellucida (BP) and Bradybaena similaris (BS) is incomplete in captivity. In interspecific copulation, BP removes its penis without transferring a spermatophore, while BS sires hybrids by inseminating BP. Thus, 'male' BP or 'female' BS rejects the other individual, while female BP and male BS accept each other, so that the two sexes of either BP or BS oppose each other in mate discrimination. Our results are a clear example of asymmetry in reproductive isolation during simultaneous reciprocal mating between hermaphroditic animals.

  10. A High-Speed High-Frequency Broadband Acoustic Modem for Short-to-Medium Range Data Transmission in Ports, Very Shallow Waters and Deep Waters Using Spread-Spectrum Modulation and Decision Feedback Equalizing

    National Research Council Canada - National Science Library

    Beaujean, Pierre-Philippe; Spruance, John; Kriel, Dion

    2006-01-01

    ...: The long-term objective is the commercialization of a high-speed high-frequency acoustic modem transmitting data at true rates of up to 105,000 bps, at a maximum range of 500 m and operate between 240 kHz and 380 kHz...

  11. Kidney disease and aging: A reciprocal relation.

    Science.gov (United States)

    Kooman, Jeroen P; van der Sande, Frank M; Leunissen, Karel M L

    2017-01-01

    Chronic kidney disease (CKD) and end-stage renal disease (ESRD) are overrepresented in elderly patients. This provides specific challenges for the treatment, as the start of dialysis in vulnerable elderly patients may be associated with a rapid decline in functional performance. However, prognosis in elderly patients with ESRD is quite variable and related to the presence of comorbidity and geriatric impairments. The decision to start dialysis in elderly patients should always be based on shared decision making, which may be aided by the use of prediction models which should however not be used to withhold dialysis treatment. The treatment of ESRD in elderly patients should be based on a multidimensional treatment plan with a role for active rehabilitation. Moreover, there also appears to be a reciprocal relationship between aging and CKD, as the presence of geriatric complications is also high in younger patients with ESRD. This has led to the hypothesis of a premature aging process associated with CKD, resulting in different phenotypes such as premature vascular aging, muscle wasting, bone disease, cognitive dysfunction and frailty. Prevention and treatment of this phenotype is based on optimal treatment of CKD, associated comorbidities, and lifestyle factors by established treatments. For the future, interventions, which are developed to combat the aging process in general, might also have relevance for the treatment of patients with CKD, but their role should always be investigated in adequately powered clinical trials, as results obtained in experimental trials may not be directly translatable to the clinical situation of elderly patients. In the meantime, physical exercise is a very important intervention, by improving both physical capacity and functional performance, as well as by a direct effect on the aging process. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Comparação do índice de desconforto sensorial durante a estimulação elétrica neuromuscular com correntes excitomotoras de baixa e média frequência em mulheres saudáveis Comparison of the sensory discomfort index during neuromuscular electrical stimulation with low and medium excitomotor frequencies in healthy women

    Directory of Open Access Journals (Sweden)

    Richard Eloin Liebano

    2009-02-01

    Full Text Available INTRODUÇÃO: A estimulação elétrica neuromuscular é uma estratégia clínica para aumento da performance muscular. Sabe-se que um dos principais fatores limitantes da estimulação elétrica para aumento de força é o desconforto causado pelas correntes utilizadas. OBJETIVO: O objetivo deste estudo foi comparar o nível de desconforto sensorial causado por correntes de baixa e média freqüência na estimulação elétrica neuromuscular do músculo quadríceps femoral. MÉTODOS: Participaram do estudo 45 voluntárias saudáveis com idade entre 18 e 30 anos. Todas as voluntárias foram submetidas à estimulação elétrica com correntes de baixa e média freqüência. A análise do desconforto sensorial foi feita por meio de uma escala visual analógica (EVA. RESULTADOS: Os resultados revelaram um valor médio de 6,1 para o desconforto sensorial na estimulação de baixa freqüência (BF e de 6,4 para a estimulação de média freqüência (MF, não havendo diferença estatisticamente significante entre elas (p = 0,61. Em relação às intensidades utilizadas, a média foi de 45,64mA para a estimulação de BF e 121,67mA na estimulação com a MF, sendo essa diferença estatisticamente significante (p INTRODUCTION: Neuromuscular electrical stimulation is a clinical strategy for increasing of muscular performance. It is known that one of the main limiting factors of the electrical stimulation for strength increase is the discomfort caused by the currents used in the process. OBJECTIVE: The objective of this study was to compare the level of sensory discomfort caused by low and medium frequency currents in the neuromuscular electrical stimulation of the quadriceps femoris muscle. METHODS: Forty-five female healthy volunteers with age between 18 and 30 years participated in the study. All the volunteers were submitted to electrical stimulation with low and medium frequency. Sensory discomfort was measured using the Visual Analogue Scale (VAS

  13. Atrioventricular reciprocal rhythm and chronic reciprocating tachycardia in a newborn infant with concealed Wolff-Parkinson-White syndrome.

    Science.gov (United States)

    Sung, R J; Ferrer, P; Garcia, O L; Castellanos, A; Gelband, H

    1977-01-01

    A case of atrioventricular reciprocal rhythm and chronic reciprocating tachycardia in a newborn infant is presented. Electrophysiological studies suggest that these rhythm disturbances are related to the presence of a right-sided atrioventricular accessory pathway capable only of retrograde conduction (concealed Wolff-Parkinson-White syndrome). The technique of recording the sequence of atrial activation during the tachycardia is described and its clinical importance emphasised. PMID:884032

  14. Non-Reciprocal on Wafer Microwave Devices

    Science.gov (United States)

    2015-05-27

    Linderman, Evangelos Economou, Yan Nie, Zbigniew Celinski. Properties of ferroelectric/ferromagnetic thin film heterostructures , Journal of Applied...A. Adeyeye, M. Kostylev, S. Samarin. Resonant frequencies of a binary magnetic nanowire , Physical Review B, (02 2013): 0. doi: 10.1103/PhysRevB

  15. Hadrons in medium

    Indian Academy of Sciences (India)

    medium properties of hadrons. I discuss the relevant symmetries of QCD and how they might affect the observed hadron properties. I then discuss at length the observable consequences of in-medium changes of hadronic properties in reactions with ...

  16. Medium is the message

    NARCIS (Netherlands)

    Kuipers, G.; Ritzer, G.

    2012-01-01

    "The medium is the message" is a phrase coined by Canadian media theorist Marshall McLuhan (1911-1980), in his book Understanding Media: The Extensions of Man (1964). In this book, McLuhan examines the impact of media on societies and human relations, arguing for the primacy of the medium -

  17. Non-reciprocal transmission in the microresonators (Conference Presentation)

    Science.gov (United States)

    Dong, Chunhua

    2017-02-01

    Non-reciprocal devices, such as circulators and isolators, are indispensable components in classical and quantum information processing in an integrated photonic circuit. Aside from those applications, the non-reciprocal phase shift is of fundamental interest for exploring exotic topological photonics, such as the realization of chiral edge states and topological protection. However, incorporating low optical-loss magnetic materials into a photonic chip is technically challenging. In this study, the non-reciprocal transmission in an optomechanical resonator is experimentally demonstrated for the first time. The underlying mechanism of the non-reciprocity demonstrated in this study is actually universal and can be generalized to any traveling wave resonators with a mechanical oscillator, such as the integrated disk-type microresonator coupled with a nanobeam. Considering that higher cooperativity and cascading of the optical devices have been reported in a photonic integrated chip, non-reciprocity in such an microresonator has applications for integrated photonic isolators and circulators, which will play important roles in a hybrid quantum Internet.

  18. The influence of reciprocating sliding wear on the oxidation behaviour of Fe-12Cr steel

    International Nuclear Information System (INIS)

    Smith, A.F.

    1988-04-01

    Medium-chromium ferritic alloys are used extensively in the boiler and core sections of advanced gas cooled reactors. It was discovered in the early 1970s, that under certain conditions these alloys could undergo the phenomenon known as breakaway oxidation. In this type of oxidation the rate limiting step is located at the oxide/metal interface rather than the more usual gas/oxide interface and results in linear oxidation kinetics. It has been shown that repeated removal of oxide layers can expose chromium depleted metal to the oxidising gas and promote nucleation of breakaway oxidation. The question has been addressed as to whether high temperature sliding wear processes can also disrupt the surface so as to make the material potentially susceptible to breakaway oxidation. To this end high temperature reciprocating wear of Fe-12Cr material in both low and high pressure reactor gas has been investigated. (author)

  19. The electrophoretic mobility of a weakly charged "soft" sphere in a charged hydrogel: application of the Lorentz reciprocal theorem.

    Science.gov (United States)

    Allison, Stuart A; Li, Fei; Hill, Reghan J

    2014-07-24

    The electrophoretic mobility of a dilute, weakly charged "soft" particle in a charged hydrogel modeled as an effective medium is investigated in this work. This is closely related to previous work (Li, F.; Allison, S. A.; Hill, R. J. J. Colloid Interface Sci. 2014, 423, 129-142) but approached in a different way using the Lorentz reciprocal theorem. Under the limiting conditions of the present work, it is possible to avoid numerical solution of differential equations. An analytical equation is derived for the mobility and applied to a number of cases.

  20. Propagation of Economic Inequality Through Reciprocity and Reputation.

    Science.gov (United States)

    Hackel, Leor M; Zaki, Jamil

    2018-04-01

    Reciprocity and reputation are powerful tools for encouraging cooperation on a broad scale. Here, we highlight a potential side effect of these social phenomena: exacerbating economic inequality. In two novel economic games, we manipulated the amount of money with which participants were endowed and then gave them the opportunity to share resources with others. We found that people reciprocated more toward higher-wealth givers, compared with lower-wealth givers, even when those givers were equally generous. Wealthier givers also achieved better reputations than less wealthy ones and therefore received more investments in a social marketplace. These discrepancies were well described by a formal model of reinforcement learning: Individuals who weighted monetary outcomes, rather than generosity, when learning about interlocutors also most strongly helped wealthier individuals. This work demonstrates that reciprocity and reputation-although globally increasing prosociality-can widen wealth gaps and provides a precise account of how inequality grows through social processes.

  1. Feasibility of Applying Controllable Lubrication Techniques to Reciprocating Machines

    DEFF Research Database (Denmark)

    Pulido, Edgar Estupinan

    The use of active lubrication in journal bearings helps to enhance the thin fluid films by increasing the fluid film thickness and consequently reducing viscous friction losses and vibrations. One refers to active lubrication when conventional hydrodynamic lubrication is combined with dynamically...... modified hydrostatic lubrication. In this case, the hydrostatic lubrication is modified by injecting oil at controllable pressures, through orifices circumferentially located around the bearing surface. In order to study the performance of journal bearings of reciprocating machines, operating under...... conventional lubrication conditions, a mathematical model of a reciprocating mechanism connected to a rigid / flexible rotor via thin fluid films was developed. The mathematical model involves the use of multibody dynamics theory for the modelling of the reciprocating mechanism (rigid bodies), finite elements...

  2. Reciprocity and conjugation fidelity in double phase conjugate mirrors

    Science.gov (United States)

    Delaye, Philippe; Fotiadi, Andrei A.; Roosen, Gerald

    1999-09-01

    It is well known that the conservation of energy in an optical system can be described by an invariant (intensity of the optical wave) during propagation. We identically show that reciprocity can be described by an invariant. This invariant is the overlap integral of two counterpropagating waves, that stays constant in every place of a reciprocal optical system. Applied to the double phase conjugate mirror (DPCM) this invariant can be rewritten as an equality between the ratio of the conjugation fidelity of the two ports of the DPCM and the ratio of the transmission in intensity of the two beams. If restricted to a plane wave case this relation becomes the well known equality of the diffraction efficiencies in both directions. We have implemented an experimental set-up that allows to show that the double phase conjugate mirror is reciprocal what confirms all the above discussion. We use the same set-up to measure the conjugation fidelity of the DPCM.

  3. Reciprocity as a Key Concept for Social Media and Society

    Directory of Open Access Journals (Sweden)

    Seth C. Lewis

    2015-04-01

    Full Text Available The concept of reciprocity, particularly in the pro-social sense of mutually beneficial exchange, presents an opportunity befitting the start of a new journal on social media. Namely, how might a concept of social exchange help us understand a mediascape increasingly dominated by social exchange—where the sharing, receiving, and recirculating of information “gifts” is central to the very social and technical frameworks on which these media function? In essence, what might reciprocity, analyzed more purposefully, reveal about social media and society? The case of “reciprocal journalism” briefly described here is but one of many avenues for studying social (media interactions and their implications, whether positive or negative.

  4. Thermodynamic Analysis of an Irreversible Maisotsenko Reciprocating Brayton Cycle

    Directory of Open Access Journals (Sweden)

    Fuli Zhu

    2018-03-01

    Full Text Available An irreversible Maisotsenko reciprocating Brayton cycle (MRBC model is established using the finite time thermodynamic (FTT theory and taking the heat transfer loss (HTL, piston friction loss (PFL, and internal irreversible losses (IILs into consideration in this paper. A calculation flowchart of the power output (P and efficiency (η of the cycle is provided, and the effects of the mass flow rate (MFR of the injection of water to the cycle and some other design parameters on the performance of cycle are analyzed by detailed numerical examples. Furthermore, the superiority of irreversible MRBC is verified as the cycle and is compared with the traditional irreversible reciprocating Brayton cycle (RBC. The results can provide certain theoretical guiding significance for the optimal design of practical Maisotsenko reciprocating gas turbine plants.

  5. Intensity and resolution of a general scan in reciprocal space

    International Nuclear Information System (INIS)

    Lebech, B.; Nielsen, M.

    1975-01-01

    Elastic neutron scattering on single crystals is traditionally carried out either by rotating the sample and keeping the detector fixed, or by coupling the detector rotation to the sample rotation in the the ratio 2:1. In recent years, a number of papers have discussed the feasibility of other types of scans. General scans at oblique angles to reciprocal lattice vectors are commonly used in inelastic neutron scattering. Such scans are also useful in elastic neutron scattering and may easily be made by means of computer or tape controlled diffractometers. Formulas are derived for the intensity and width of Bragg reflections measured by scanning at oblique angles to reciprocal lattice vectors. The results of the calculations are compared to experimental results on simple structures. The limitations of general scans in reciprocal space are also discussed

  6. Bayesian analysis of rotating machines - A statistical approach to estimate and track the fundamental frequency

    DEFF Research Database (Denmark)

    Pedersen, Thorkild Find

    2003-01-01

    frequency and the related frequencies as orders of the fundamental frequency. When analyzing rotating or reciprocating machines it is important to know the running speed. Usually this requires direct access to the rotating parts in order to mount a dedicated tachometer probe. In this thesis different......Rotating and reciprocating mechanical machines emit acoustic noise and vibrations when they operate. Typically, the noise and vibrations are concentrated in narrow frequency bands related to the running speed of the machine. The frequency of the running speed is referred to as the fundamental...

  7. Local interstellar medium

    International Nuclear Information System (INIS)

    Crutcher, R.M.; and Radio Astronomy Laboratory, University of California, Berkeley)

    1982-01-01

    Analysis of the velocities of optical interstellar lines shows that the Sun is immersed in a coherently moving local interstellar medium whose velocity vector agrees with that of the interstellar wind observed through backscatter of solar H Lyα and He lambda584 photons. The local interstellar medium consists of both cool clouds and warm intercloud medium gas, has a mass of perhaps approx.30 M/sub sun/, does not have severe depletion of trace elements from the gas phase, and appears to be material which has been shocked and accelerated by stellar winds and supernovae associated with the Sco-Oph OB association

  8. Acetification of rice wine by Acetobacter aceti using loofa sponge in a low-cost reciprocating shaker.

    Science.gov (United States)

    Krusong, W; Tantratian, S

    2014-11-01

    To maximize acetification rate (ETA) by adsorption of acetic acid bacteria (AAB) on loofa sponge matrices (LSM). AAB were adsorbed on LSM, and the optimal shaking rate was determined for maximized AAB growth and oxygen availability. Results confirm that the 1 Hz reciprocating shaking rate with 40% working volume (liquid volume 24 l, tank volume 60 l) achieved a high oxygen transfer coefficient (k(L)a). The highest ETA was obtained at 50% (w:v) LSM-AAB:culture medium at 30 ± 2°C (P ≤ 0·05). To test process consistency, nine sequential acetification cycles were run using LSM-AAB and comparing it with no LSM. The highest ETA (1·701-2·401 g l(-1) d(-1)) was with LSM-AAB and was associated with the highest biomass of AAB, confirmed by SEM images. Results confirm that LSM-AAB works well as an inert substrate for AAB. High oxygenation was maintained by a reciprocating shaker. Both shaking and LSM were important in increasing ETA. High cell biomass in LSM-AAB provides good conditions for higher ETAs of quick acetification under adequate oxygen transfer by reciprocating shaker. It is a sustainable process for small-scale vinegar production system requiring minimal set-up cost. © 2014 The Society for Applied Microbiology.

  9. Fairness and Reciprocity in the Hawk-Dove Game

    DEFF Research Database (Denmark)

    Poulsen, Anders; Neugebauer, Tibor; Schram, Arthur

    2002-01-01

    We study fairness and reciprocity in a Hawk-Dove game, using an experimental approach. This allows us to test various models in one framework. We observe a large extent of selfish and rational behavior. Our results are inconsistent with leading models in this field.......We study fairness and reciprocity in a Hawk-Dove game, using an experimental approach. This allows us to test various models in one framework. We observe a large extent of selfish and rational behavior. Our results are inconsistent with leading models in this field....

  10. Development of timber reciprocal frame structures in the UK

    OpenAIRE

    CHILTON, John

    2010-01-01

    p. 1877-1884 Although the structural principle of closed circuits of mutually supporting beams was known by Leonardo Da Vinci and has been used for hundreds, if not thousands of years (Popovic Larsen [8]), its rediscovery and renaming as the Reciprocal Frame, by the designer Graham Brown in 1987, has led to more structures of this type being built in the UK over the last 20 years. This paper briefly traces the development of reciprocal frames in the UK from Brown¿s first simple...

  11. HIRENASD medium unstructured

    Data.gov (United States)

    National Aeronautics and Space Administration — Unstructured HIRENASD mesh: - medium size (16 million nodes, 39 million elements) - for node centered solvers - 31.05.2011 - caution: dimensions in mm

  12. Concept medium programme

    DEFF Research Database (Denmark)

    Bjerrum, Peter

    2005-01-01

    The present essay is an attempt to determine the architectural project of the 21st century in relation to a modern conception of space as the medium of architecture, and of sociality as its program...

  13. Concept medium programme

    DEFF Research Database (Denmark)

    Bjerrum, Peter

    2005-01-01

    The present essay is an attempt to determine the architectural project of the 21st century in relation to a modern conception of space as the medium of architecture, and of sociality as its program......The present essay is an attempt to determine the architectural project of the 21st century in relation to a modern conception of space as the medium of architecture, and of sociality as its program...

  14. The use of ferrites at microwave frequencies

    CERN Document Server

    Thourel, Léo

    1964-01-01

    The Use of Ferrites at Microwave Frequencies describes the applications of ferrites at microwave frequencies and the apparatus involved. Topics covered range from the properties of ferrites to gyromagnetic and non-reciprocal effects, ferrite isolators, circulators, and modulators. The use of ferrites in variable frequency filter cavities is also discussed. Mathematical explanations are reduced to the strict minimum and only the results of calculations are indicated. This book consists of seven chapters and opens with a review of the theory of magnetism, touching on subjects such as the BOHR m

  15. Defined medium for Moraxella bovis.

    OpenAIRE

    Juni, E; Heym, G A

    1986-01-01

    A defined medium (medium MB) for Moraxella bovis was formulated. Nineteen strains grew well on medium MB. One strain was auxotrophic for asparagine, and another was auxotrophic for methionine. Strains of M. equi and M. lacunata also grew on medium MB. All strains had an absolute requirement for thiamine and were stimulated by or actually required the other growth factors in the medium.

  16. Modeling time-lagged reciprocal psychological empowerment-performance relationships.

    Science.gov (United States)

    Maynard, M Travis; Luciano, Margaret M; D'Innocenzo, Lauren; Mathieu, John E; Dean, Matthew D

    2014-11-01

    Employee psychological empowerment is widely accepted as a means for organizations to compete in increasingly dynamic environments. Previous empirical research and meta-analyses have demonstrated that employee psychological empowerment is positively related to several attitudinal and behavioral outcomes including job performance. While this research positions psychological empowerment as an antecedent influencing such outcomes, a close examination of the literature reveals that this relationship is primarily based on cross-sectional research. Notably, evidence supporting the presumed benefits of empowerment has failed to account for potential reciprocal relationships and endogeneity effects. Accordingly, using a multiwave, time-lagged design, we model reciprocal relationships between psychological empowerment and job performance using a sample of 441 nurses from 5 hospitals. Incorporating temporal effects in a staggered research design and using structural equation modeling techniques, our findings provide support for the conventional positive correlation between empowerment and subsequent performance. Moreover, accounting for the temporal stability of variables over time, we found support for empowerment levels as positive influences on subsequent changes in performance. Finally, we also found support for the reciprocal relationship, as performance levels were shown to relate positively to changes in empowerment over time. Theoretical and practical implications of the reciprocal psychological empowerment-performance relationships are discussed. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  17. Aging, Neighborhood Attachment, and Fear of Crime: Testing Reciprocal Effects

    Science.gov (United States)

    Oh, Joong-Hwan; Kim, Sangmoon

    2009-01-01

    This study attempts to examine the reciprocal effects between fear of crime and neighborhood attachment because aging is a critical factor in both discussions of fear of crime and neighborhood attachment (friendship, neighboring, social cohesion and trust, informal social control, and participation in neighborhood watch program). Using data from…

  18. Reciprocal Category Analysis in Major Fields of Psychotherapy.

    Science.gov (United States)

    Morgan, Clifford O.; Stricherz, Mathias E.

    Client-therapist verbal interaction in content analysis research has just begun to be defined. Reciprocal Category Analysis (RCA) is used to measure therapeutic interactions between client and therapist. Three experienced therapists from each of the schools of client-centered, Rational Emotive (RET), Transactional Analysis (TA), and Gestalt…

  19. Reciprocal locomotion of dense swimmers in Stokes flow

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Rodriguez, David [Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Lauga, Eric [Department of Mechanical and Aerospace Engineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0411 (United States)], E-mail: davidgr@alum.mit.edu, E-mail: elauga@ucsd.edu

    2009-05-20

    Due to the kinematic reversibility of Stokes flow, a body executing a reciprocal motion (a motion in which the sequence of body configurations remains identical under time reversal) cannot propel itself in a viscous fluid in the limit of negligible inertia; this result is known as Purcell's scallop theorem. In this limit, the Reynolds numbers based on the fluid inertia and on the body inertia are all zero. Previous studies characterized the breakdown of the scallop theorem with fluid inertia. In this paper we show that, even in the absence of fluid inertia, certain dense bodies undergoing reciprocal motion are able to swim. Using Lorentz's reciprocal theorem, we first derive the general differential equations that govern the locomotion kinematics of a dense swimmer. We demonstrate that no reciprocal swimming is possible if the body motion consists only of tangential surface deformation (squirming). We then apply our general formulation to compute the locomotion of four simple swimmers, each with a different spatial asymmetry, that perform normal surface deformations. We show that the resulting swimming speeds (or rotation rates) scale as the first power of a properly defined 'swimmer Reynolds number', demonstrating thereby a continuous breakdown of the scallop theorem with body inertia.

  20. Social Dilemmas and Indirect Reciprocity: A systematic review

    Directory of Open Access Journals (Sweden)

    Cristian Acosta

    2014-08-01

    Full Text Available Indirect reciprocity is an evolutionary theory of altruism and cooperation in social dilemmas. Its explanation of cooperation incorporates information on the reputation people hold of other people regarding whether they are cooperative or not. This study systematically reviewed the current empirical literature on indirect reciprocity in social dilemma situations. The following databases were consulted: ScienceDirect, EBSCO, and OVID, using has key words "indirect reciprocity" AND "dilemma" OR "cooperation" OR "charity". Twenty-three articles were selected which met the inclusion criteria (papers written in English and studies whose methodology was based on experimental games and the theories, objectives, the main types of samples used, and main results were analyzed. The results show that the games used were the indirect reciprocity and public goods games, which may vary according to the objectives. It was found that reputation is a key variable that helps to promote cooperation. In turn, information on previous cooperation helps to build reputation, which is subsequently involved in the decision to cooperate with others. Finally, we highlight the need for more experimental studies that incorporate other explanatory variables and evaluate them in new contexts.

  1. Longitudinal Study on Reciprocity between Personality Traits and Parenting Stress

    Science.gov (United States)

    Rantanen, Johanna; Tillemann, Kati; Metsäpelto, Riitta-Leena; Kokko, Katja; Pulkkinen, Lea

    2015-01-01

    Reciprocal associations between the Big Five personality traits and parenting stress--including both parents' feelings of their distress and perception of their incompetence as parents--were studied with 248 participants (49% of which were males). Longitudinal data, collected at ages 33/36, 42 and 50 years, were used. Cross-lagged path analysis…

  2. Potential Reciprocal Relationship between Motivation and Achievement: A Longitudinal Study

    Science.gov (United States)

    Liu, Yuan; Hou, Shumeng

    2018-01-01

    Among the non-cognitive factors that influence academic achievement, intrinsic motivation has been found to be a potential reciprocal factor. The present study aims to determine the causal relationship between other types of motivation and academic achievement. For this purpose, a large-scale data survey, the National Education Longitudinal Study…

  3. Achievement Emotions and Academic Performance: Longitudinal Models of Reciprocal Effects

    Science.gov (United States)

    Pekrun, Reinhard; Lichtenfeld, Stephanie; Marsh, Herbert W.; Murayama, Kou; Goetz, Thomas

    2017-01-01

    A reciprocal effects model linking emotion and achievement over time is proposed. The model was tested using five annual waves of the Project for the Analysis of Learning and Achievement in Mathematics (PALMA) longitudinal study, which investigated adolescents' development in mathematics (Grades 5-9; N = 3,425 German students; mean starting…

  4. This White 'I': The Reciprocal Shame of Oppressor and Oppressed ...

    African Journals Online (AJOL)

    This White 'I': The Reciprocal Shame of Oppressor and Oppressed. A Hurst. Abstract. Vice's answer to the question of this white 'I' who must try to live well in South Africa, configures shame, political silence and humble self-reconfiguration. I accept her insightful analysis of 'whiteness' in terms of the oppressor's shame, but ...

  5. Evidence of Reciprocity in Reports on International Partnerships

    Directory of Open Access Journals (Sweden)

    Rachel A. Umoren

    2012-01-01

    Full Text Available The increase in global health opportunities in medical education has been accompanied by calls for ethical and reciprocal institutional partnerships. The Working Group on Ethics Guidelines in Global Health Training (WEIGHT guidelines were developed in 2010 and are widely accepted by the global health community. We reviewed 43 articles on international partnerships from 1970 to 2010 for eight principles of reciprocity derived from the WEIGHT guidelines. The results showed that, while few articles reflected all principles, there was a trend to increasing consideration of the international partner’s local needs, pre-departure cultural training, and collaborative authorship. However, learner supervision and consideration of local cost/benefit ratios decreased over the same time period. Partnerships with only one international partner or with institutional partners in Africa had lower reciprocity scores than those with two or more partners and institutional partners in Asia and South America. We recommend that a new focus on ethics in global health partnerships leads to the inclusion of the principles of reciprocity in model program descriptions in order to enable and encourage ethical, sustainable, and mutually beneficial institutional partnerships.

  6. A Reciprocal Peer Review System to Support College Students' Writing

    Science.gov (United States)

    Yang, Yu-Fen

    2011-01-01

    As students' problem-solving processes in writing are rarely observed in face-to-face instruction, they have few opportunities to participate collaboratively in peer review to improve their texts. This study reports the design of a reciprocal peer review system for students to observe and learn from each other when writing. A sample of 95…

  7. Reciprocity in International Affairs: An Analysis of Nigeria/South ...

    African Journals Online (AJOL)

    This paper analysed the March 2012 yellow fever diplomatic row between Nigeria and South Africa. It argued that the principle of reciprocity in international relations came to the fore in the row. The paper made the point that the row was a mild explosion of underlying tensions between the two African giants. An issue is the ...

  8. Emerging signs of strong reciprocity in human ontogeny

    Directory of Open Access Journals (Sweden)

    Erin eRobbins

    2011-12-01

    Full Text Available Strong reciprocity is considered here as the propensity to sacrifice resources to be kind or to punish in response to prior acts, a behavior not simply reducible to self-interest and a likely force behind human cooperation and sociality. The aim was to capture emerging signs of strong reciprocity in human ontogeny. Three- and five-year-old middle class American children (N=162 were tested in a simple, multiple round, three-way sharing game involving the child, a generous puppet, and a stingy puppet. At the end of the game, the child was offered an opportunity to sacrifice some of her personal gains to punish one of the puppets. By three years, American children demonstrate a willingness to engage in costly punishment. However, only five-year-olds show some evidence of strong reciprocity by orienting their punishment systematically toward the stingy puppet. Further analyses and 3 additional control conditions demonstrate that such propensity is not simply reducible to a straight imitation, or b inequity aversion. To assess the relative universality of such development, a group of five- to six-year-old children from rural Samoa (N=14 were tested and compared to age and gender matched American children. Samoan children did not manifest the same propensity toward strong reciprocity. The results are interpreted as pointing to 1 the developmental emergence of an ethical stance between three and five years of age, and 2 that the expression of such stance by young children could depend on culture.

  9. Generation of the reciprocal-binomial state for optical fields

    International Nuclear Information System (INIS)

    Valverde, C.; Avelar, A.T.; Baseia, B.; Malbouisson, J.M.C.

    2003-01-01

    We compare the efficiencies of two interesting schemes to generate truncated states of the light field in running modes, namely the 'quantum scissors' and the 'beam-splitter array' schemes. The latter is applied to create the reciprocal-binomial state as a travelling wave, required to implement recent experimental proposals of phase-distribution determination and of quantum lithography

  10. Reciprocal relationships between job demands, job resources, and recovery opportunities

    NARCIS (Netherlands)

    A. Rodríguez-Muñoz (Alfredo); A.I. Sanz-Vergel (Ana Isabel); E. Demerouti (Eva); A.B. Bakker (Arnold)

    2012-01-01

    textabstractThe aim of this study was to explore longitudinal relationships between job demands, job resources, and recovery opportunities. On the basis of the Job Demands-Resources model and Conservation of Resources theory we hypothesized that we would find reciprocal relations between job

  11. Cardiovascular response to resistive and non-resistive reciprocal ...

    African Journals Online (AJOL)

    Background: Reciprocal pulley exercise is usually recommended for physiotherapy patients undergoing rehabilitation for muscle strengthening exercises or improvement in joint range of motion but, very little is known of its effects on the cardiovascular system. Aims: This study aimed at investigating the blood pressure and ...

  12. Evaluation of layer type chickens under reciprocal recurrent selection

    African Journals Online (AJOL)

    Matings within pure male and female lines, and between pure male and female lines were carried out to produce purebred male line (AA x AA), female line (BB x BB), cross (AA x BB) and reciprocal cross (BB x AA). A total number of 364 pullets arising from 207 hens and 23 cocks in generation 1 and 440 pullets from 70 ...

  13. Apical extrusion of debris using reciprocating files and rotary ...

    African Journals Online (AJOL)

    ... the other groups, with the exception of the Typhoon group (P < 0.05). Conclusion: According to our study, all systems caused apical debris extrusion. However, the Reciproc group was associated with less debris extrusion when compared to the other groups. Key words: Apical extrusion, endodontics, single file systems ...

  14. Pharmacological treatment of young children with permanent junctional reciprocating tachycardia

    NARCIS (Netherlands)

    van Stuijvenberg, M; Beaufort-Krol, GCM; Haaksma, J; Bink-Boelkens, MTE

    2003-01-01

    Our objective was to assess the efficacy of pharmacological treatment in reducing the incidence of permanent junctional reciprocating tachycardia in young children, or to bring the mean heart rate over 24 h to a normal level. We included 21 children with a median age of 0.05 year seen with permanent

  15. Teacher, Team, and School Change through Reciprocal Learning

    Science.gov (United States)

    Cherkowski, Sabre; Schnellert, Leyton

    2018-01-01

    This paper documents the first year of a qualitative case study investigating the experiences of reciprocal learning teams of teachers within a small, rural secondary school. The purpose of this study was to examine how teachers experienced collaborative professional development (PD) and how their experiences contributed to developing the culture…

  16. Self-Esteem and Adolescent Problems: Modeling Reciprocal Effects.

    Science.gov (United States)

    Rosenberg, Morris; And Others

    1989-01-01

    Explores the reciprocal relationships between self-esteem and the following three problems of youth: (1) juvenile delinquency; (2) poor school performance; and (3) psychological depression. Findings include the following: (1) low self-esteem fosters delinquency, which may enhance self-esteem; (2) school performance affects self-esteem; and (3)…

  17. The Reciprocal Organization of Constructive Activity in Drug Addiction

    Science.gov (United States)

    Akhmetzyanova, Anna I.; Nikishina, Vera B.; Klyueva, Nadezhda V.; Petrash, Ekaterina A.

    2016-01-01

    The urgency of the problem stated in the article is caused by the fact that modern scientific studies show that sustainable neuro-associative connections with the object of addiction arise at chemical addiction. The aim of this study is to examine the features of the reciprocal organization of constructive activities in drug addiction. Study of…

  18. Modified condylotomy versus conventional conservative treatment in painful reciprocal clicking

    DEFF Research Database (Denmark)

    Bakke, Merete; Eriksson, Lars; Thorsen, Niels Max

    2008-01-01

    patients, 19-44 years of age, with severe painful reciprocal clicking. Before and after treatment, assessments were performed by subjective reports, clinical recordings, and blinded evaluations of radiography and magnetic resonance imaging (MRI). Based on the clinical evaluations before treatment, all...

  19. Paradoxical Effects of Feedback in International Online Reciprocal Peer Tutoring

    Science.gov (United States)

    Topping, K. J.; Dehkinet, R.; Blanch, S.; Corcelles, M.; Duran, D.

    2013-01-01

    This paper reports an online reciprocal peer tutoring project for improving language competence in Spanish and English. Students aged 9-12 years from Scotland and Catalonia were matched to act as tutors in their own language and as tutees in a modern foreign language. Students were intended to improve both their first language (through helping the…

  20. Reciprocity and its utilization in ultrasonic flow meters

    Energy Technology Data Exchange (ETDEWEB)

    Lunde, Per; Vestrheim, Magne; Boe, Reidar; Smoergrav, Skule; Abrahamsen, Atle K.

    2005-07-01

    In ultrasonic transit time flow meters for gas and liquid (USMs), the flow direction, the flow velocity and the sound velocity are estimated from the measured up- and downstream transit times. At no-flow conditions, the up- and downstream transit times of such meters should ideally be the same, or the difference should be negligible. This may not be the case unless special precautions are made. In order to reduce the possibility of the meter to detect a false flow at no-flow conditions, USMs are typically ''dry calibrated'' before being installed in the field. ''Dry calibration'' (which may be made in different ways), in general involves measurement of (a) the time delays due to electronics, cables and transducers, (b) the so called ''{delta}t-correction'' (for each acoustic path, also denoted ''zero flow offset factor''), and (c) geometrical parameters. Various {delta}t-correction approaches may be used by different manufacturers, but these are basically similar and have the same purpose: to reduce the false flow detection and improve the accuracy at low and no-flow conditions (''zero flow adjustment''), without significantly affecting the accuracy at the high velocity measurements. The AGA-9 report and the API MPMS Ch. 5.8 standard both prescribe need for ''zero flow verification test (zero test)'' or ''zeroing the meter'', for gas and liquid USMs, respectively. Advances in USM technology based on the electro acoustic reciprocity principle have provided methods for reduction or even neglect ion of the need for ''{delta} t-correction'' of USMs. That means, if the USM measurement system is reciprocal, and operated in a ''sufficiently reciprocal'' way, the ''{delta}t-correction'' may be negligibly small over the operational range of pressure and temperature, and

  1. The reciprocal relations between morphological processes and reading.

    Science.gov (United States)

    Kruk, Richard S; Bergman, Krista

    2013-01-01

    Reciprocal relations between emerging morphological processes and reading skills were examined in a longitudinal study tracking children from Grade 1 through Grade 3. The aim was to examine predictive relationships between productive morphological processing involving composing and decomposing of inflections and derivations, reading ability for pseudoword and word decoding, and word and passage reading comprehension after controlling for initial abilities in reading, morphological processing, phonological awareness, and vocabulary. Reciprocal influences were indicated by predictive relations among initial morphological processes and later reading abilities co-occurring with relationships between initial reading abilities and later morphological processes. Using multilevel modeling, decomposing and composing were found to predict emerging word decoding and word and passage comprehension but not pseudoword decoding. Reading comprehension predicted growth in decomposing. Subsequent regression analyses of model-estimated early linear growth in predictors and later linear growth in outcomes showed that early growth in morphological processes predicted later growth in word decoding and passage comprehension. Although reciprocal relations between emerging morphological processes and reading skills were observed, the different patterns on each side of the reciprocal "coin" indicated that the mechanisms underlying predictive influences are likely different but related to quality of lexical representations. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Reciprocal Teaching of Comprehension Strategies Improves EFL Learners' Writing Ability

    Science.gov (United States)

    Ghorbani, Mohammad Reza; Gangeraj, Atefeh Ardeshir; Alavi, Sahar Zahed

    2013-01-01

    Although the importance of reading in developing writing ability is undeniable, few competent readers in EFL contexts develop into competent writers. Since students are not aware that reading can assist them in writing, this study examined the effect of reciprocal teaching--which focuses on four reading comprehension strategies, namely…

  3. Reciprocal genomic evolution in the ant-fungus agricultural symbiosis

    DEFF Research Database (Denmark)

    Nygaard, Sanne; Hu, Haofu; Li, Cai

    2016-01-01

    The attine ant-fungus agricultural symbiosis evolved over tens of millions of years, producing complex societies with industrial-scale farming analogous to that of humans. Here we document reciprocal shifts in the genomes and transcriptomes of seven fungus-farming ant species and their fungal...

  4. Performance of oysters in reciprocal transplants between two ...

    African Journals Online (AJOL)

    Oyster spat were reciprocally transplanted between Benya Lagoon at Elmina and Nakwa Lagoon at Nakwa and grown on cultches. Shell growth, dry meat weight, and survival of the transplants were monitored for at least six months and compared with their counterparts at their new locations as well as their places of origin.

  5. Reciprocal Relationships between Math Self-Concept and Math Anxiety

    NARCIS (Netherlands)

    Ahmed, Wondimu; Minnaert, Alexander; Kuyper, Hans; Van der Werf, Greetje

    The present study examined the reciprocal relationships between self-concept and anxiety in mathematics. A sample of 495 grade 7 students (51% girls) completed self-report measures assessing self-concept and anxiety three times in a school year. Structural equation modeling was used to test a

  6. Grooming reciprocity in female tibetan macaques macaca thibetana.

    Science.gov (United States)

    Xia, Dongpo; Li, Jinhua; Garber, Paul A; Sun, Lixing; Zhu, Yong; Sun, Binghua

    2012-06-01

    Grooming among nonhuman primates is widespread and may represent an important service commodity that is exchanged within a biological marketplace. In this study, using focal animal sampling methods, we recorded grooming relationships among 12 adult females in a free-ranging group of Tibetan macaques (Macaca thibetana) at Huangshan, China, to determine the influence of rank and kinship on grooming relationships, and whether females act as reciprocal traders (exchange grooming received for grooming given) or interchange traders (interchange grooming for social tolerance or other commodities). The results showed that: (1) grooming given was positively correlated with grooming received; (2) kinship did not exert a significant influence on grooming reciprocity; and (3) grooming reciprocity occurred principally between individuals of adjacent rank; however, when females of different rank groomed, females tended to groom up the hierarchy (lower ranking individuals groomed higher ranking individuals more than vice versa). Our results support the contention that both grooming reciprocity and the interchange of grooming for tolerance represent important social tactics used by female Tibetan macaques. © 2012 Wiley Periodicals, Inc.

  7. Unilateral or Reciprocal Climate Policy? Experimental Evidence from China

    Directory of Open Access Journals (Sweden)

    Thomas Bernauer

    2016-09-01

    Full Text Available The traditional political economy account of global climate change governance directs our attention to fundamental collective action problems associated with global public goods provision, resulting from positive or negative externalities as well as freeriding. The governance architecture of the 1997 Kyoto Protocol uses the traditional approaches of international diplomacy for addressing such challenges: legally binding commitments based on principles of reciprocity and (fair cost/burden sharing via formalized carbon-budgeting. Yet, the 2015 Paris Agreement has essentially abandoned this approach, as it now operates on the basis of internationally coordinated and monitored unilateralism. On the presumption that public opinion matters for government policy, we examine how citizens view this shift in climate policy from reciprocity to unilateralism, after many years of exposure to strong reciprocity rhetoric by governments and stakeholders. To that end, we fielded a survey experiment in China, the world’s largest greenhouse gas (GHG emitter. The results show that there is, perhaps surprisingly, strong and robust public support for unilateral, non-reciprocal climate policy. To the extent China is interested in pushing ahead with ambitious and thus costly GHG reduction policies, our results suggest that China can leverage segments of public support in order to overcome domestic obstacles to GHG mitigation policies.

  8. 32 CFR 634.16 - Reciprocal state-military action.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Reciprocal state-military action. 634.16 Section 634.16 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) LAW ENFORCEMENT AND CRIMINAL INVESTIGATIONS MOTOR VEHICLE TRAFFIC SUPERVISION Driving Privileges § 634.16...

  9. Exogenous selection rather than cytonuclear incompatibilities shapes asymmetrical fitness of reciprocal Arabidopsis hybrids.

    Science.gov (United States)

    Muir, Graham; Ruiz-Duarte, Paola; Hohmann, Nora; Mable, Barbara K; Novikova, Polina; Schmickl, Roswitha; Guggisberg, Alessia; Koch, Marcus A

    2015-04-01

    Reciprocal crosses between species often display an asymmetry in the fitness of F1 hybrids. This pattern, referred to as isolation asymmetry or Darwin's corollary to Haldane's rule, is a general feature of reproductive isolation in plants, yet factors determining its magnitude and direction remain unclear. We evaluated reciprocal species crosses between two naturally hybridizing diploid species of Arabidopsis to assess the degree of isolation asymmetry at different postmating life stages. We found that pollen from Arabidopsis arenosa will usually fertilize ovules from Arabidopsis lyrata; the reverse receptivity being less complete. Maternal A. lyrata parents set more F1 hybrid seed, but germinate at lower frequency, reversing the asymmetry. As predicted by theory, A. lyrata (the maternal parent with lower seed viability in crosses) exhibited accelerated chloroplast evolution, indicating that cytonuclear incompatibilities may play a role in reproductive isolation. However, this direction of asymmetrical reproductive isolation is not replicated in natural suture zones, where delayed hybrid breakdown of fertility at later developmental stages, or later-acting selection against A. arenosa maternal hybrids (unrelated to hybrid fertility, e.g., substrate adaptation) may be responsible for an excess of A. lyrata maternal hybrids. Exogenous selection rather than cytonuclear incompatibilities thus shapes the asymmetrical postmating isolation in nature.

  10. Stochasticity in economic losses increases the value of reputation in indirect reciprocity.

    Science.gov (United States)

    dos Santos, Miguel; Placì, Sarah; Wedekind, Claus

    2015-12-14

    Recent theory predicts harsh and stochastic conditions to generally promote the evolution of cooperation. Here, we test experimentally whether stochasticity in economic losses also affects the value of reputation in indirect reciprocity, a type of cooperation that is very typical for humans. We used a repeated helping game with observers. One subject (the "Unlucky") lost some money, another one (the "Passer-by") could reduce this loss by accepting a cost to herself, thereby building up a reputation that could be used by others in later interactions. The losses were either stable or stochastic, but the average loss over time and the average efficiency gains of helping were kept constant in both treatments. We found that players with a reputation of being generous were generally more likely to receive help by others, such that investing into a good reputation generated long-term benefits that compensated for the immediate costs of helping. Helping frequencies were similar in both treatments, but players with a reputation to be selfish lost more resources under stochastic conditions. Hence, returns on investment were steeper when losses varied than when they did not. We conclude that this type of stochasticity increases the value of reputation in indirect reciprocity.

  11. 75 FR 75937 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2010-12-07

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines... internal combustion engines. Subsequently, the Administrator received two petitions for reconsideration... Any industry using a stationary 2211 Electric power reciprocating internal generation, combustion...

  12. 75 FR 37732 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2010-06-30

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines... hazardous air pollutants for existing stationary compression ignition reciprocating internal combustion... combustion engines. 40 CFR 63.6590 was amended by revising paragraphs (b)(1) and (3). Inadvertently...

  13. 77 FR 60341 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2012-10-03

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New Source Performance Standards for Stationary Internal Combustion Engines AGENCY: Environmental Protection... Pollutants for Stationary Reciprocating Internal Combustion Engines to solicit comment on specific issues...

  14. 77 FR 37361 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2012-06-21

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New Source Performance Standards for Stationary Internal Combustion Engines AGENCY: Environmental Protection... Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New Source Performance...

  15. 76 FR 79051 - Airworthiness Directives; Lycoming Engines, Fuel Injected Reciprocating Engines

    Science.gov (United States)

    2011-12-21

    ... reciprocating engines manufactured by Lycoming Engines that incorporate externally mounted fuel injection lines.... (3) This AD is not applicable to engines having internally mounted fuel injection lines, which are... Airworthiness Directives; Lycoming Engines, Fuel Injected Reciprocating Engines AGENCY: Federal Aviation...

  16. Evidence of direct reciprocity, but not of indirect and generalized reciprocity, in the grooming exchanges of wild Barbary macaques (Macaca sylvanus).

    Science.gov (United States)

    Molesti, Sandra; Majolo, Bonaventura

    2017-09-01

    Reciprocity is one of the mechanisms that have been proposed to explain the exchange of social behaviors, such as grooming, in animals. Reciprocity assumes that individuals act as the donor and recipient of grooming and switch roles over time to balance the benefits and costs of this behavior. Three main patterns of reciprocity may follow a grooming given: (i) direct reciprocity, where the former recipient returns the grooming to the former donor; (ii) indirect reciprocity, where another individual returns the grooming to the former donor; and (iii) generalized reciprocity, where the former recipient returns the grooming to another individual. While there is evidence that direct reciprocity plays an important role in various species of animals, the role of indirect and generalized reciprocity is less clear and has been rarely analyzed. We tested the role of direct, indirect, and generalized reciprocity in explaining grooming exchanges of wild Barbary macaques, by analyzing the temporal contingency between giving and receiving grooming. We collected the occurrence and latency of the three types of grooming reciprocation during 1 hr long focal sessions run simultaneously on two partners who just stopped grooming (post-grooming session) or who were in proximity (i.e., within 1.5 m) without grooming each other (control session). We ran the analyses on 284 post-grooming and 63 control sessions. The results revealed a temporal contingency of grooming interactions exchanged according to direct reciprocity but not according to indirect or generalized reciprocity. Our results indicate that grooming distribution in Barbary macaques is partner-specific. We discuss the possible role of cognition and emotions in explaining direct reciprocity in animals. © 2017 Wiley Periodicals, Inc.

  17. Transcranial electrical neuromodulation based on the reciprocity principle

    Directory of Open Access Journals (Sweden)

    Mariano eFernandez Corazza

    2016-05-01

    Full Text Available A key challenge in multi-electrode transcranial electrical stimulation (TES or transcranial direct current stimulation (tDCS is to find a current injection pattern that delivers the necessary current density at a target and minimizes it in the rest of the head, which is mathematically modelled as an optimization problem. Such an optimization with the Least Squares (LS or Linearly Constrained Minimum Variance (LCMV algorithms is generally computationally expensive and requires multiple independent current sources. Based on the reciprocity principle in electroencephalography (EEG and TES, it could be possible to find the optimal TES patterns quickly whenever the solution of the forward EEG problem is available for a brain region of interest. Here, we investigate the reciprocity principle as a guideline for finding optimal current injection patterns in TES that comply with safety constraints. We define four different trial cortical targets in a detailed seven-tissue finite element head model, and analyze the performance of the reciprocity family of TES methods in terms of electrode density, targeting error, focality, intensity, and directionality using the LS and LCMV solutions as the reference standards. It is found that the reciprocity algorithms show good performance comparable to the LCMV and LS solutions. Comparing the 128 and 256 electrode cases, we found that use of greater electrode density improves focality, directionality, and intensity parameters. The results show that reciprocity principle can be used to quickly determine optimal current injection patterns in TES and help to simplify TES protocols that are consistent with hardware and software availability and with safety constraints.

  18. Some properties of generalized self-reciprocal polynomials over finite fields

    Directory of Open Access Journals (Sweden)

    Ryul Kim

    2014-07-01

    Full Text Available Numerous results on self-reciprocal polynomials over finite fields have been studied. In this paper we generalize some of these to a-self reciprocal polynomials defined in [4]. We consider some properties of the divisibility of a-reciprocal polynomials and characterize the parity of the number of irreducible factors for a-self reciprocal polynomials over finite fields of odd characteristic.

  19. Spiegel. Medium. Kunst

    DEFF Research Database (Denmark)

    Kacunko, Slavko

    and cultural perspective. From 1800 on, the great incentive was to push forward the material-physical and optical-mechanical and especially the media ‘exploitation’ of the mirror. The significance of the mirror as a central meta-medium of the visual emerged in a particularly striking way in the late 1830s....... That ricochets through media theory, theories of art and culture and through cultural historiography. A repository is one thing, a transmitter another: the distinction will act crucially on the quest for appropriate perspectives and classifications of what in terms of disciplines would rather appear...... or as synaesthesia gone mute. It stands in contrast with the mirror, which assumes the status of a medium facility or meta-medium of visual transference, encountering its only medial and operative limitation within the analogue or digital repository media. The present proposal for an artistic and cultural history...

  20. Lack of reciprocity among Dutch teachers: Validation of reciprocity indices and their relation to stress and well-being

    NARCIS (Netherlands)

    Horn, J.E. van; Schaufeli, W.B.; Taris, T.W.

    2001-01-01

    This research presents the results of two related studies on the convergent and construct validity of three measures of reciprocity in exchange relationships at work. In Study 1, 71 Dutch teachers were interviewed about their specific investments and outcomes in the exchange relationships with their

  1. The Effect of Reciprocal Peer Tutoring and Non-Reciprocal Peer Tutoring on the Performance of Students in College Physics

    Science.gov (United States)

    Dioso-Henson, Luzale

    2012-01-01

    Formalised peer-to-peer collaboration and the use of web-enhanced materials that are consistent with course objectives, graded assessments and learning outcomes is well known in educational practice. This study compared the academic gains of college students enrolled in Physics using Reciprocal Peer Tutoring (RPT) with others using non-Reciprocal…

  2. Efficiency of the Self Adjusting File, WaveOne, Reciproc, ProTaper and hand files in root canal debridement

    Science.gov (United States)

    Topcu, K. Meltem; Karatas, Ertugrul; Ozsu, Damla; Ersoy, Ibrahim

    2014-01-01

    Objectives: The aim of this study was to compare the canal debridement capabilities of three single file systems, ProTaper, and K-files in oval-shaped canals. Materials and Methods: Seventy-five extracted human mandibular central incisors with oval-shaped root canals were selected. A radiopaque contrast medium (Metapex; Meta Biomed Co. Ltd., Chungcheongbuk-do, Korea) was introduced into the canal systems and the self-adjusting file (SAF), WaveOne, Reciproc, ProTaper, and K-files were used for the instrumentation of the canals. The percentage of removed contrast medium was calculated using pre- and post-operative radiographs. Results: An overall comparison between the groups revealed that the hand file (HF) and SAF groups presented the lowest percentage of removed contrast medium, whereas the WaveOne group showed the highest percentage (P < 0.001). The ProTaper group removed more contrast medium than the SAF and HF groups (P < 0.05). Conclusions: None of the instruments was able to remove the contrast medium completely. WaveOne performed significantly better than other groups. PMID:25202211

  3. A Comparison of Several Statistical Tests of Reciprocity of Self-Disclosure.

    Science.gov (United States)

    Dindia, Kathryn

    1988-01-01

    Reports the results of a study that used several statistical tests of reciprocity of self-disclosure. Finds little evidence for reciprocity of self-disclosure, and concludes that either reciprocity is an illusion, or that different or more sophisticated methods are needed to detect it. (MS)

  4. 76 FR 56637 - Airworthiness Directives; Lycoming Engines Model IO-720-A1B Reciprocating Engines

    Science.gov (United States)

    2011-09-14

    ... Airworthiness Directives; Lycoming Engines Model IO-720-A1B Reciprocating Engines AGENCY: Federal Aviation... directive (AD) for certain model IO-720-A1B Lycoming Engines reciprocating engines. This AD requires a... two Lycoming Engines model IO- 720-A1B reciprocating engines, installed on airplanes of U.S. registry...

  5. DYNAMIC DEFORMATION THE VISCOELASTIC TWOCOMPONENT MEDIUM

    Directory of Open Access Journals (Sweden)

    V. S. Polenov

    2015-01-01

    Full Text Available Summary. In the article are scope harmonious warping of the two-component medium, one component which are represent viscoelastic medium, hereditary properties which are described by the kernel aftereffect Abel integral-differential ratio BoltzmannVolterr, while second – compressible liquid. Do a study one-dimensional case. Use motion equation of two-component medium at movement. Look determination system these equalization in the form of damped wave. Introduce dimensionless coefficient. Combined equations happen to homogeneous system with complex factor relatively waves amplitude in viscoelastic component and in fluid. As a result opening system determinant receive biquadratic equation. Elastic operator express through kernel aftereffect Abel for space Fourier. With the help transformation and symbol series biquadratic equation reduce to quadratic equation. Come to the conclusion that in two-component viscoelastic medium exist two mode sonic waves. As a result solution of quadratic equation be found description advance of waves sonic in viscoelastic two-component medium, which physical-mechanical properties represent complex parameter. Velocity determination advance of sonic waves, attenuation coefficient, mechanical loss tangent, depending on characteristic porous medium and circular frequency formulas receive. Graph dependences of description advance of waves sonic from the temperature logarithm and with the fractional parameter γ are constructed.

  6. The reciprocal relationship between alliance and symptom improvement across treatment of childhood anxiety

    Science.gov (United States)

    Marker, Craig D.; Comer, Jonathan S.; Abramova, Viktoriya; Kendall, Philip C.

    2012-01-01

    Objective This study examined changes in the therapeutic alliance and in self-reported anxiety over the course of 16 weeks of manual-based family treatment for child anxiety disorders. Method 86 children (51.3% female; aged 7.15 to 14.44; 86.2% Caucasian, 14.8% minority) with a principal diagnosis of separation anxiety disorder, generalized anxiety disorder, and/or social phobia, and their parents, received family treatment for anxiety disorders in youth. Child, therapist, and parent ratings of therapeutic alliance and child ratings of state anxiety were measured each session. Latent difference score growth modeling investigated the interacting relationship. Results Therapeutic alliance change, as rated by the mother and by the therapist, was a significant predictor (medium effect) of latter change in child anxiety (with greater therapeutic alliance leading to later reduction in anxiety). However, changes in child-reported anxiety also predicted latter change in father- and therapist-reported alliance (small-to-medium effect). Prospective relationships between child-reported therapeutic alliance and child-reported symptom improvement were not significant. Conclusions Results provide partial support for a reciprocal model in which therapeutic alliance improves outcome, and anxiety reduction improves therapeutic alliance. PMID:23009693

  7. The reciprocal relationship between alliance and symptom improvement across the treatment of childhood anxiety.

    Science.gov (United States)

    Marker, Craig D; Comer, Jonathan S; Abramova, Viktoriya; Kendall, Philip C

    2013-01-01

    This study examined changes in the therapeutic alliance and in self-reported anxiety over the course of 16 weeks of manual-based family treatment for child anxiety disorders. Eighty-six children (51.3% female; aged 7.15-14.44; 86.2% Caucasian, 14.8% minority) with a principal diagnosis of separation anxiety disorder, generalized anxiety disorder, and/or social phobia, and their parents, received family treatment for anxiety disorders in youth. Child, therapist, and parent ratings of therapeutic alliance and child ratings of state anxiety were measured each session. Latent difference score growth modeling investigated the interacting relationship. Therapeutic alliance change, as rated by the mother and by the therapist, was a significant predictor (medium effect) of latter change in child anxiety (with greater therapeutic alliance leading to later reduction in anxiety). However, changes in child-reported anxiety also predicted latter change in father- and therapist-reported alliance (small-to-medium effect). Prospective relationships between child-reported therapeutic alliance and child-reported symptom improvement were not significant. Results provide partial support for a reciprocal model in which therapeutic alliance improves outcome, and anxiety reduction improves therapeutic alliance.

  8. Concept medium program

    DEFF Research Database (Denmark)

    Bjerrum, Peter

    2003-01-01

    The present essays is an attempt to dertermine the architecural project of the 21st century in realation to a modern conception of space as the medium of architecture, and of society as its program. This attempt adopts the internal point of view of an architect in describing a modern architectura...

  9. Radon in geological medium

    International Nuclear Information System (INIS)

    Hricko, J.

    1995-01-01

    The paper presented deals with behavior of the radon in geological medium and with some results of the radon survey in Bratislava and Kosice regions. 1) The a v has been detected in the holes 0.80 m deep. The density of observations - 3 reference areas (one represents 20 stations) per 1 km 2 . The radon risk maps in 1:25000 and 1:50000 scales have been compiled. The 56.8% of the project area lies in low radon risk, 37.6% in medium radon risk and 5.6% in high radon risk. Follow-up monitoring of the equivalent volume radon activity (EVRA) at the flats, located in the areas with high radon risk of the surface layer, has showed values several times higher than Slovak limits (Marianka, Raca, Vajnory). The evidence that neotectonic is excellent medium for rising up emanation to the subsurface layer, is shown on the map. The tectonic zone of Liscie udolie in Bratislava-Karlova Ves area has been clearly detected by profile radon survey (a v > 50 kBq/m 3 ). 2) At present, northern half of the area of Kosice in question was covered by radon survey. The low and medium radon risks have been observed here, while localities with high radon risk are small in extent. The part of radon risk and soil permeability map from northern Kosice area is shown. (J.K.) 3 figs., 2 refs

  10. Estimulação elétrica neuromuscular de média freqüência (russa em cães com atrofia muscular induzida Medium frequency neuromuscular electrical stimulation (russian in dogs with induced muscle atrophy

    Directory of Open Access Journals (Sweden)

    Charles Pelizzari

    2008-06-01

    Full Text Available A estimulação elétrica neuromuscular (EENM de média freqüência (Russa ou de Kotz pode ser empregada para a recuperação de massa muscular em animais apresentando atrofia muscular por desuso. Assim, o objetivo deste trabalho foi empregar a EENM de média freqüência no quadríceps femoral de cães com atrofia muscular induzida, avaliando-se a ocorrência de ganho de massa. Foram utilizados oito cães em dois grupos denominados de GI ou controle e de GII ou tratado. Para a indução da atrofia muscular, a articulação fêmoro-tíbio-patelar esquerda foi imobilizada por 30 dias. Após 48 horas da remoção, foi realizada a EENM nos cães do grupo II, três vezes por semana, com intervalo de 48 horas cada sessão, pelo período de 60 dias. Foram avaliadas a mensuração da perimetria da coxa, da goniometria do joelho, as enzimas creatina-quinase (CK e morfometria das fibras musculares em cortes transversais do músculo vasto lateral, colhido mediante a biópsia muscular. A EENM foi empregada no músculo quadríceps femoral numa freqüência de 2.500Hz, largura de pulso de 50% e relação de tempo on/off de 1:2. Não houve diferença significativa quanto aos valores de perimetria da coxa e a atividade da enzima CK entre os grupos I e II. Na goniometria, houve diminuição significativa (PThe medium frequency neuromuscular electrical stimulation (NMES (Russa or Kotz is designed for recuperation of muscle mass in dogs with muscular atrophy in disuse. This study aims to utilize medium frequency NMES on the femoral quadriceps of dogs with induced muscular atrophy and evaluate the occurrence of gain in mass. Eight dogs in two groups denominated GI, or control, and GII, or treated were used. For the induction of muscular atrophy, the left femoral-tibial-patellar joint was immobilized for 30 days. NMES treatment began 48 hours after the removal of the immobilization device on dogs from group II and was carried out three times per week, with an

  11. Effect of switching-off of a plasma medium on a traveling wave

    International Nuclear Information System (INIS)

    Kalluri, D.K.

    1989-01-01

    It is known that a sudden creation of a plasma medium of plasma frequency ω ρ splits a traveling wave of frequency ω o into two new waves of frequencies. The negative value for the frequency here indicates a reflected wave. The effect of a sudden collapse of the plasma medium, on a travelling wave of frequency ω o is shown to be the creation of two new waves of frequencies. A numerical solution is obtained for the case of a gradual collapse of the plasma medium. For the case of a slow decay of the particle density an approximate WKB type solution is obtained. Several results are presented

  12. Indirect Reciprocity with Optional Interactions and Private Information

    Directory of Open Access Journals (Sweden)

    Jason Olejarz

    2015-09-01

    Full Text Available We consider indirect reciprocity with optional interactions and private information. A game is offered between two players and accepted unless it is known that the other person is a defector. Whenever a defector manages to exploit a cooperator, his or her reputation is revealed to others in the population with some probability. Therefore, people have different private information about the reputation of others, which is a setting that is difficult to analyze in the theory of indirect reciprocity. Since a defector loses a fraction of his social ties each time he exploits a cooperator, he is less efficient at exploiting cooperators in subsequent rounds. We analytically calculate the critical benefit-to-cost ratio above which cooperation is successful in various settings. We demonstrate quantitative agreement with simulation results of a corresponding Wright–Fisher process with optional interactions and private information. We also deduce a simple necessary condition for the critical benefit-to-cost ratio.

  13. Intimate Partner Violence: A Rare Case of Reciprocal Homicide.

    Science.gov (United States)

    Cauchois, Aurélie; Paraire, François; Lorin de la Grandmaison, Geoffroy

    2017-06-01

    We present the case of a reciprocal homicide by stabbing that occurred within an unmarried couple without known history of spousal violence. Each partner killed the other one at the same time and at the same place using kitchen knives. They were both found dead at home lying on the floor after the neighbors heard an argument and screams coming from the couple's apartment, so they called the police and the fire department. The door was locked from the inside, and the fire department was forced to break the door. Two kitchen knives supporting blood traces were found at the scene. At autopsy, both bodies showed multiple stab wounds, and the lethal ones were due to heart injuries. Defense injuries were also found in both bodies. To our knowledge, this is the first case of reciprocal homicide described in the literature. Other manners of death are discussed, including homicide by a third party, homicide-suicide, and suicide pact.

  14. Hybrid Optimization in the Design of Reciprocal Structures

    DEFF Research Database (Denmark)

    Parigi, Dario; Kirkegaard, Poul Henning; Sassone, Mario

    2012-01-01

    . In this paper it is shown that the geometrically compatible position of the elements could be determined by local search algorithm gradient-based (GB). However the control on which bar sit on the top or in the bottom at each connection can be regarded as a topological problem and require the use of algorithms...... that explore the global domain of solutions as genetic algorithms (GAs). The benchmark tests show that when the control on the topology is required the best result is obtained by a hybrid approach that combines the global search of the GA with the local search of a GB algorithm. The optimization method......The paper presents a method to generate the geometry of reciprocal structures by means of a hybrid optimization procedure. The geometry of reciprocal structures where elements are sitting on the top or in the bottom of each other is extremely difficult to predict because of the non...

  15. Balanced reciprocal translocation 5,18: a case report

    Directory of Open Access Journals (Sweden)

    Shahram Savad

    2014-05-01

    Conclusion: A balanced reciprocal translocation carrier is phenotypically normal, but during meiosis І, carrier chromosomes cant pair normally and form quadrivalant instead of bivalant that depend on type of their segregation (alternate, adjacent 1, adjacent 2,3:1,4:0, produce gametes that are chromosomally unbalanced which can result in early fetus abortion. Considering the number of abnormal gametes, the most effective way to help couples with this problem seems to be PGD 24sure, since it can identify reciprocal and Robertsonian translocation and allows concurrent screening of all chromosomes for aneuploidy. Another technique that can be compared with PGD 24sure is fluorescence in situ hybridization (FISH, but it has several technical limitations such as it is expensive and complexity, in addition it has only few probes (for chromosomes 21, 13, 18, X, Y so sometimes necessary to create patient specific protocols.

  16. Marital conflict and children's sleep: reciprocal relations and socioeconomic effects.

    Science.gov (United States)

    Kelly, Ryan J; El-Sheikh, Mona

    2011-06-01

    We examined reciprocal relations between parental marital conflict and children's sleep disruptions over two years. The roles of ethnicity (African American and European American) and socioeconomic status were tested as moderators of the examined relations. A community sample of 176 school-age children (M age = 8.68 at T1) and their parents participated at T1 and T2 with a 2-year interval between waves. Mothers, fathers, and children reported on parental marital conflict, and children's sleep was measured via actigraphy and self-reports. Latent variable modeling indicated that T1 marital conflict predicted increases in children's sleep disruptions longitudinally; results were more pronounced for African American children and those from lower SES homes. Further, children's sleep disruptions at T1 predicted increases in marital conflict over time. Results demonstrate the importance of reciprocal relations between a prevalent familial stressor and a fundamental facet of children's health, especially when considering the sociocultural milieu. 2011 APA, all rights reserved

  17. Measuring reciprocity in high functioning children and adolescents with autism spectrum disorders.

    Science.gov (United States)

    van Ommeren, Tineke Backer; Begeer, Sander; Scheeren, Anke M; Koot, Hans M

    2012-06-01

    Few instruments have been developed that measure impairments in reciprocity, a defining feature of autism. We introduce a new test assessing the quality of reciprocal behaviour: the interactive drawing test (IDT). Children and adolescents (n = 49) with and without high functioning autism spectrum disorders (HFASD) were invited to collaborate with an experimenter in making a joint drawing. Within both groups the performance on collaborative reciprocity improved with age. However, compared to the control group, HFASD participants showed less collaborative and more basic reciprocal behaviour and preferred to draw their own objects. They were less tolerant of the experimenter's input as well. Performance on the IDT was independent of estimated verbal IQ. Reciprocal behaviour in self-initiated objects corresponded with more parental reported autistic traits, while reciprocal behaviour in other-initiated objects corresponded with less autistic traits. The findings of this study suggest that IDT is a promising instrument to assess reciprocity.

  18. An Examination of Reciprocal Influences in Sport Socialization

    OpenAIRE

    海老原, 修; 横山, 文人; 宮下, 充正

    1989-01-01

    This study was designed to clarify reciprocal influences in sport socialization. Parent-effects were assessed by their sport involvement before their child participated in organized sport, whereas child-effects were measured by a parent's attitudinal and behavioral changes of sport involvement caused by a child's participation. Eight indicators of sport involvement were selected as follows: 3 types of interest in sport involvement such as activities, sport consumption, and sport activity in o...

  19. On the general Dedekind sums and its reciprocity formula

    Indian Academy of Sciences (India)

    Introduction. For a positive integer q and an arbitrary integer h, the Dedekind sums S(h, q) is defined as: S(h, q) = ... we obtain an interesting reciprocity formula for the general Dedekind sums S(h, 1, 3,q). That is, we ..... [3] Conrey J B, Fransen Eric, Klein Robert and Scott Clayton, Mean values of Dedekind sums,. J. Number ...

  20. Emerging Signs of Strong Reciprocity in Human Ontogeny

    Science.gov (United States)

    Robbins, Erin; Rochat, Philippe

    2011-01-01

    Strong reciprocity is considered here as the propensity to sacrifice resources to be kind or to punish in response to prior acts, a behavior not simply reducible to self-interest and a likely force behind human cooperation and sociality. The aim was to capture emerging signs of strong reciprocity in human ontogeny and across highly contrasted cultures. Three- and 5-year-old middle class American children (N = 162) were tested in a simple, multiple round, three-way sharing game involving the child, a generous puppet, and a stingy puppet. At the end of the game, the child was offered an opportunity to sacrifice some of her personal gains to punish one of the puppets. By 3 years, American children demonstrate a willingness to engage in costly punishment. However, only 5-year-olds show some evidence of strong reciprocity by orienting their punishment systematically toward the stingy puppet. Further analyses and three additional control conditions demonstrate that such propensity is not simply reducible to (a) straight imitation, or (b) inequity aversion. To assess the relative universality of such development, a group of 5- to 6-year-old children from rural Samoa (N = 14) were tested and compared to age and gender-matched American children. Samoan children did not manifest the same propensity toward strong reciprocity. The results are interpreted as pointing to (1) the developmental emergence of an ethical stance between 3 and 5 years of age, and (2) that the expression of such stance by young children could depend on culture. PMID:22194730

  1. Achievement emotions and academic performance: longitudinal models of reciprocal effects

    OpenAIRE

    Pekrun, Reinhard; Lichtenfeld, Stephanie; Marsh, Herbert, W.; Murayama, Kou; Goetz, Thomas

    2017-01-01

    A reciprocal effects model linking emotion and achievement over time is proposed. The model was tested using five annual waves of the PALMA longitudinal study, which investigated adolescents’ development in mathematics (grades 5-9; N=3,425 German students; mean starting age=11.7 years; representative sample). Structural equation modeling showed that positive emotions (enjoyment, pride) positively predicted subsequent achievement (math end-of-the-year grades and test scores), and that achievem...

  2. Dedicated monitoring and machinery protection systems on reciprocating compressors

    Energy Technology Data Exchange (ETDEWEB)

    Grande, Alvaro; Wenisch, Markus [Hoerbiger Ventilwerke GmbH and Co KG, Wien (Austria); Jacobs, Denis [HOERBIGER do Brasil Industria de Equipamentos, Cajamar, SP (Brazil)

    2012-07-01

    Growing demands on reciprocating compressors (recips) in the process gas industry require particular solutions for machinery protection and performance monitoring systems. Compared to rotating equipment, monitoring systems for recips have to consider the special mechanical and physical characteristics, such as oscillating masses, variable vibration behaviour and varying operating conditions. Furthermore, they provide valuable information about the performance of cylinder related components allowing the operator the optimization of efficiency and availability, and therefore increase production. (author)

  3. A Low Friction Thrust Bearing for Reciprocating Compressors

    OpenAIRE

    Nagata, Shuhei; Kousokabe, Hirokatsu; Sekiyama, Nobuya; Ono, Toshiaki

    2012-01-01

    A thrust bearing with a micro texture on its sliding surface that produces hydrodynamic pressure was developed for use in reciprocating compressors. Evaluation using an elemental friction test showed that its friction loss was 20–60 % lower than that of the current design. Measurement of the efficiency of a compressor with the developed thrust bearing showed that the coefficient of performance was 1.4 % higher than that of a compressor with a conventional thrust bearing.

  4. Novel Long Stroke Reciprocating Compressor for Energy Efficient Jaggery Making

    Science.gov (United States)

    Rane, M. V.; Uphade, D. B.

    2017-08-01

    Novel Long Stroke Reciprocating Compressor is analysed for jaggery making while avoiding burning of bagasse for concentrating juice. Heat of evaporated water vapour along with small compressor work is recycled to enable boiling of juice. Condensate formed during heating of juice is pure water, as oil-less compressor is used. Superheat of compressor is suppressed by flow of superheated vapours through condensate. It limits heating surface temperature and avoids caramelization of sugar. Thereby improves quality of jaggery and eliminates need to use chemicals for colour improvement. Stroke to bore ratio is 0.6 to 1.2 in conventional reciprocating drives. Long stroke in reciprocating compressors enhances heat dissipation to surrounding by providing large surface area and increases isentropic efficiency by reducing compressor outlet temperature. Longer stroke increases inlet and exit valve operation timings, which reduces inertial effects substantially. Thereby allowing use of sturdier valves. This enables handling liquid along with vapour in compressors. Thereby supressing the superheat and reducing compressor power input. Longer stroke increases stroke to clearance ratios which increases volumetric efficiency and ability of compressor to compress through higher pressure ratios efficiently. Stress-strain simulation is performed in SolidWorks for gear drive. Long Stroke Reciprocating Compressor is developed at Heat Pump Laboratory, stroke/bore 292 mm/32 mm. It is operated and tested successfully at different speeds for operational stability of components. Theoretical volumetric efficiency is 93.9% at pressure ratio 2.0. Specific energy consumption is 108.3 kWhe/m3 separated water, considering free run power.

  5. A reciprocal Wald theorem for varying gravitational function

    International Nuclear Information System (INIS)

    Fay, Stephane

    2004-01-01

    We study when a cosmological constant is a natural issue if it is mimicked by the potential of a massive Hyperextended Scalar Tensor theory with a perfect fluid for Bianchi type I and V models. We then deduce a reciprocal Wald theorem giving the conditions such that the potential tends to a non vanishing constant when the gravitational function varies. We also get the conditions allowing the potential to vanish or diverge. (orig.)

  6. Reciprocal Modulation of Cognitive and Emotional Aspects in Pianistic Performances

    OpenAIRE

    Higuchi, Marcia K. Kodama; Fornari, José; Del Ben, Cristina M.; Graeff, Frederico G.; Leite, João Pereira

    2011-01-01

    Background: High level piano performance requires complex integration of perceptual, motor, cognitive and emotive skills. Observations in psychology and neuroscience studies have suggested reciprocal inhibitory modulation of the cognition by emotion and emotion by cognition. However, it is still unclear how cognitive states may influence the pianistic performance. The aim of the present study is to verify the influence of cognitive and affective attention in the piano performances. Methods an...

  7. Variable speed hermetic reciprocating compressors for domestic refrigerators

    DEFF Research Database (Denmark)

    Rasmussen, Bjarne D.

    1998-01-01

    This article describes the results of a both theoretical and experimental investigation of the performance of variable speed hermetic reciprocating compressors for domestic refrigerators. The investigation was performed as a part of a larger research project with the objective of reducing...... the energy consumption of domestic refrigerators by increasing the efficiency of the refrigeration system. The improvement of the system efficiency was to be obtained by introducing continuous operation and use variable speed compressors for controlling the capacity of the refrigeration system...

  8. On the general Dedekind sums and its reciprocity formula

    Indian Academy of Sciences (India)

    if x is an integer. The various properties of S(h, q) were investigated by many authors. Maybe the most famous property of Dedekind sums is the reciprocity formula (see [2–4]):. S(h, q) + S(q, h) = h2 + q2 + 1. 12hq. −. 1. 4. (1) for all (h, q) = 1,q > 0,h> 0. The main purpose of this paper is to introduce a general. Dedekind sum:.

  9. Ultrasound fields in an attenuating medium

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Gandhi,, D; O'Brien,, W.D., Jr.

    1993-01-01

    of the rectangles and sums all contributions to arrive at the spatial impulse response for the aperture and field point. This approach makes it possible to model all transducer apertures, and the program can readily calculate the emitted, pulse-echo and continuous wave field. Attenuation is included by splitting...... it into a frequency dependent part and frequency independent part. The latter results in an attenuation factor that is multiplied onto the responses from the individual elements, and the frequency dependent part is handled by attenuating the basic one-dimensional pulse. The influence on ultrasound fields from......Ultrasound fields propagating in tissue will undergo changes in shape not only due to diffraction, but also due to the frequency dependent attenuation. Linear fields can be fairly well predicted for a non-attenuating medium like water by using the Tupholme-Stepanishen method for calculating...

  10. Medium-energy physics

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    One of the basic challenges of medium-energy physics is the development of a clear picure of the manner in which pions propagate in nuclear matter. Since the pion is a basic quantum of the nuclear force, understanding its propagation in nuclei contributes to our understanding of the basic nature of nuclear forces. Key to such understanding is a comprehensive and precise experimental description of pion interactions both with complex nuclei and few nucleon systems. This is a major objective of the ANL effort in medium-energy physics. Experiments are carried out as a part of a comprehensive nuclear program, and, because of this perspective, the pion studies are expected to give new insights into the nature of nuclear forces. At the present time, almost all experimental activity is concentrated on measurements using various pion beams of the Los Alamos Meson Physics Facility

  11. Reciprocity and the Emergence of Power Laws in Social Networks

    Science.gov (United States)

    Schnegg, Michael

    Research in network science has shown that many naturally occurring and technologically constructed networks are scale free, that means a power law degree distribution emerges from a growth model in which each new node attaches to the existing network with a probability proportional to its number of links (= degree). Little is known about whether the same principles of local attachment and global properties apply to societies as well. Empirical evidence from six ethnographic case studies shows that complex social networks have significantly lower scaling exponents γ ~ 1 than have been assumed in the past. Apparently humans do not only look for the most prominent players to play with. Moreover cooperation in humans is characterized through reciprocity, the tendency to give to those from whom one has received in the past. Both variables — reciprocity and the scaling exponent — are negatively correlated (r = -0.767, sig = 0.075). If we include this effect in simulations of growing networks, degree distributions emerge that are much closer to those empirically observed. While the proportion of nodes with small degrees decreases drastically as we introduce reciprocity, the scaling exponent is more robust and changes only when a relatively large proportion of attachment decisions follow this rule. If social networks are less scale free than previously assumed this has far reaching implications for policy makers, public health programs and marketing alike.

  12. Partner Choice Drives the Evolution of Cooperation via Indirect Reciprocity.

    Directory of Open Access Journals (Sweden)

    Gilbert Roberts

    Full Text Available Indirect reciprocity potentially provides an important means for generating cooperation based on helping those who help others. However, the use of 'image scores' to summarize individuals' past behaviour presents a dilemma: individuals withholding help from those of low image score harm their own reputation, yet giving to defectors erodes cooperation. Explaining how indirect reciprocity could evolve has therefore remained problematic. In all previous treatments of indirect reciprocity, individuals are assigned potential recipients and decide whether to cooperate or defect based on their reputation. A second way of achieving discrimination is through partner choice, which should enable individuals to avoid defectors. Here, I develop a model in which individuals choose to donate to anyone within their group, or to none. Whereas image scoring with random pairing produces cycles of cooperation and defection, with partner choice there is almost maximal cooperation. In contrast to image scoring with random pairing, partner choice results in almost perfect contingency, producing the correlation between giving and receiving required for cooperation. In this way, partner choice facilitates much higher and more stable levels of cooperation through image scoring than previously reported and provides a simple mechanism through which systems of helping those who help others can work.

  13. Microscopic Perspective on Photovoltaic Reciprocity in Ultrathin Solar Cells.

    Science.gov (United States)

    Aeberhard, Urs; Rau, Uwe

    2017-06-16

    The photovoltaic reciprocity theory relates the electroluminescence spectrum of a solar cell under applied bias to the external photovoltaic quantum efficiency of the device as measured at short circuit conditions. Its derivation is based on detailed balance relations between local absorption and emission rates in optically isotropic media with nondegenerate quasiequilibrium carrier distributions. In many cases, the dependence of density and spatial variation of electronic and optical device states on the point of operation is modest and the reciprocity relation holds. In nanostructure-based photovoltaic devices exploiting confined modes, however, the underlying assumptions are no longer justifiable. In the case of ultrathin absorber solar cells, the modification of the electronic structure with applied bias is significant due to the large variation of the built-in field. Straightforward use of the external quantum efficiency as measured at short circuit conditions in the photovoltaic reciprocity theory thus fails to reproduce the electroluminescence spectrum at large forward bias voltage. This failure is demonstrated here by numerical simulation of both spectral quantities at normal incidence and emission for an ultrathin GaAs p-i-n solar cell using an advanced quantum kinetic formalism based on nonequilibrium Green's functions of coupled photons and charge carriers. While coinciding with the semiclassical relations under the conditions of their validity, the theory provides a consistent microscopic relationship between absorption, emission, and charge carrier transport in photovoltaic devices at arbitrary operating conditions and for any shape of optical and electronic density of states.

  14. A reciprocal framework for spatial K-anonymity

    KAUST Repository

    Ghinita, Gabriel

    2010-05-01

    Spatial K-anonymity (SKA) exploits the concept of K-anonymity in order to protect the identity of users from location-based attacks. The main idea of SKA is to replace the exact location of a user U with an anonymizing spatial region (ASR) that contains at least K-1 other users, so that an attacker can pinpoint U with probability at most 1/K. Simply generating an ASR that includes K users does not guarantee SKA. Previous work defined the reciprocity property as a sufficient condition for SKA. However, the only existing reciprocal method, Hilbert Cloak, relies on a specialized data structure. In contrast, we propose a general framework for implementing reciprocal algorithms using any existing spatial index on the user locations. We discuss ASR construction methods with different tradeoffs on effectiveness (i.e., ASR size) and efficiency (i.e., construction cost). Then, we present case studies of applying our framework on top of two popular spatial indices (namely, R*-trees and Quad-trees). Finally, we consider the case where the attacker knows the query patterns of each user. The experimental results verify that our methods outperform Hilbert Cloak. Moreover, since we employ general-purpose spatial indices, the proposed system is not limited to anonymization, but supports conventional spatial queries as well. © 2009 Elsevier B.V. All rights reserved.

  15. Reciprocal burnout model: Interconnectedness of interpersonal and intrapersonal factors

    Directory of Open Access Journals (Sweden)

    Andreja Pšeničny

    2007-01-01

    Full Text Available Burnout can be described as chronic state of extreme psychophysical and emotional exhaustion. Burning out is a stage process consisting of: the stage of exhaustion, the stage of captivity and the final stage – adrenal burnout. Adrenal burnout syndrome (ABS is the final stage of burning out process, resulting in a functional blocade of hypothalamic-pituitary-adrenal axis which causes secondary cortisol insufficiency. Even though they share similar symptoms, burnout and depression are two different types of disorder. They differ mainly in basic cortisol levels and self-esteem. Researchers tend to link the burnout syndrome and environmental stress (interpersonal causes. Recently, some of them found connection between burnout syndrome and personality traits (intrapersonal causes. Reciprocal burnout model links both causes. It shows that in the same circumstances only a few people suffer from adrenal burnout syndrome. It states that personal characteristics are one of the main causes why people suffering from burnout syndrome enroll in nonreciprocal personal and professional relations. Socialization process plays an important role in development of personality traits. The core of the reciprocal burnout model consists of one's attitude towards his or her basic needs' fulfillment, personal system of values, and correlation between fulfillment of basic needs (energy accumulation and burning out process (energy consumption. Reciprocal burnout model is opening a series of questions, concerning the connection between personality traits, life satisfaction and personal values, and burnout syndrome risk behavior, as well as the influence of whole life circumstances on burning out process.

  16. Liquid chromatographic extraction medium

    Science.gov (United States)

    Horwitz, E. Philip; Dietz, Mark L.

    1994-01-01

    A method and apparatus for extracting strontium and technetium values from biological, industrial and environmental sample solutions using a chromatographic column is described. An extractant medium for the column is prepared by generating a solution of a diluent containing a Crown ether and dispersing the solution on a resin substrate material. The sample solution is highly acidic and is introduced directed to the chromatographic column and strontium or technetium is eluted using deionized water.

  17. Hadrons in the medium

    International Nuclear Information System (INIS)

    Leupold, Stefan

    2005-01-01

    QCD, the theory of the strong interaction, has a non-trivial vacuum structure. One way to characterize this structure is by means of non-vanishing matrix elements of quark or gluon operators, the condensates. In hot and/or dense enough strongly interacting media, QCD is subject to phase transitions or rapid crossovers. Consequently, the condensates typically change with density and temperature. An exciting aspect of hadron physics is the question how these changes affect the properties of hadrons which are put in a strongly interacting environment. Here vector mesons deserve special attention as they couple directly to (virtual) photons. The latter can decay into dileptons which leave the strongly interacting system untouched. Via that process information about possible in-medium modifications of the vector mesons can be carried to the detectors. With the ω-meson as an example I will review our current understanding of the connections between in-medium changes of condensates and the in-medium changes of the properties of hadrons. (author)

  18. Radiculography with reduced amounts of contrast medium

    International Nuclear Information System (INIS)

    Signorini, E.; Caputo, N.; Chiurulla, C.; Ciorba, E.; Pelliccioli, G.P.; Cianciulli, E.

    1984-01-01

    Because of the frequency and seriousness of side effects observed after radiculography, due to, among the other things, the amount of contrast medium, the authors describe a method that gives diagnostically satisfactory results using a low dose of contrast and a tangent-beam technique. Among 106 patients undergoing radiculography with a tangent-beam technique and Iopamidol, only 4 developed mild side effects, namely headache in three cases and headache with nausea in one. (Author)

  19. Primary and reciprocal space-time experiments, relativistic reciprocity relations and Einstein's train-embankment thought experiment

    OpenAIRE

    Field, J. H.

    2008-01-01

    The concepts of primary and reciprocal experiments and base and travelling frames in special relativity are concisely described and applied to several different space-time experiments. These include Einstein's train/embankment thought experiment and a related thought experiment, due to Sartori, involving two trains in parallel motion with different speeds. Spatially separated clocks which are synchronised in their common proper frame are shown to be so in all inertial frames and their spatial...

  20. Spiegel. Medium. Kunst

    DEFF Research Database (Denmark)

    Kacunko, Slavko

    to human talent, came the millennia of untiring labours and the play of art and science and thought. The human love-affair with reflection (to cite Mark Pendergast’s subtitle - Mirror/Mirror: A History of the Human Love Affair with Reflection [New York 2003]) has always been a platonic one and I hold...... and cultural perspective. From 1800 on, the great incentive was to push forward the material-physical and optical-mechanical and especially the media ‘exploitation’ of the mirror. The significance of the mirror as a central meta-medium of the visual emerged in a particularly striking way in the late 1830s...

  1. DENSE MEDIUM CYCLONE OPTIMIZATON

    Energy Technology Data Exchange (ETDEWEB)

    Gerald H. Luttrell; Chris J. Barbee; Peter J. Bethell; Chris J. Wood

    2005-06-30

    Dense medium cyclones (DMCs) are known to be efficient, high-tonnage devices suitable for upgrading particles in the 50 to 0.5 mm size range. This versatile separator, which uses centrifugal forces to enhance the separation of fine particles that cannot be upgraded in static dense medium separators, can be found in most modern coal plants and in a variety of mineral plants treating iron ore, dolomite, diamonds, potash and lead-zinc ores. Due to the high tonnage, a small increase in DMC efficiency can have a large impact on plant profitability. Unfortunately, the knowledge base required to properly design and operate DMCs has been seriously eroded during the past several decades. In an attempt to correct this problem, a set of engineering tools have been developed to allow producers to improve the efficiency of their DMC circuits. These tools include (1) low-cost density tracers that can be used by plant operators to rapidly assess DMC performance, (2) mathematical process models that can be used to predict the influence of changes in operating and design variables on DMC performance, and (3) an expert advisor system that provides plant operators with a user-friendly interface for evaluating, optimizing and trouble-shooting DMC circuits. The field data required to develop these tools was collected by conducting detailed sampling and evaluation programs at several industrial plant sites. These data were used to demonstrate the technical, economic and environmental benefits that can be realized through the application of these engineering tools.

  2. Chronic Medical Conditions and Negative Affect; Racial Variation in Reciprocal Associations

    Directory of Open Access Journals (Sweden)

    Shervin Assari

    2016-08-01

    Full Text Available Background: Black-White health paradox can be defined as a lower frequency of depression despite a higher prevalence of economic and social adversities as well as chronic medical conditions (CMC among American Blacks compared to American Whites. Based on this paradox, the CMC - depressive symptoms link is expected to be weaker among Blacks and Whites. We conducted a 10 year longitudinal study to compare Blacks and Whites for bidirectional associations between number of CMC and negative affect.Methods: We used data from the MIDUS (Midlife in the United States, a nationally representative longitudinal study of American adults. A total number of 7,108 individuals with age range 25 to 75 (N = 7,108 were followed for 10 years from 1995 to 2004. Age, gender, and socioeconomic status (education and income measured at baseline were controls. Negative affect and chronic medical conditions were measured at baseline and end of follow up. Race was the moderator. Linear regression analysis was used to test the moderating effect of race on the reciprocal associations between CMC and negative affect, net of covariates.Results: In the pooled sample, while baseline CMC was predictive of an increase in negative affect over time, baseline negative affect was also predictive of an increase in CMC. We found interactions between race and baseline CMC on change in depressive symptoms, as well as race with negative affect on CMC change. Conclusion: Blacks and Whites differ in reciprocal links between CMC and negative affect over time. This finding replicates recent studies on differential links between psychosocial outcomes and physical health based on race. Findings may help us better understand how Black - White health paradox develops across mid and later life.

  3. Chronic Medical Conditions and Negative Affect; Racial Variation in Reciprocal Associations Over Time.

    Science.gov (United States)

    Assari, Shervin; Lankarani, Maryam Moghani

    2016-01-01

    The Black-White health paradox can be defined as lower frequency of depression despite higher prevalence of economic and social adversities as well as chronic medical conditions (CMC) among American Blacks compared to American Whites. Based on this paradox, the CMC - depressive symptoms link is expected to be weaker among Blacks than Whites. We conducted a 10-year longitudinal study to compare Blacks and Whites for bidirectional associations between number of CMC and negative affect over time. We used data from the MIDUS (Midlife in the United States), a nationally representative longitudinal study of American adults. A total number of 7,108 individuals with an age range of 25-75 years (N = 7,108) were followed for 10 years from 1995 to 2004. Age, gender, and socioeconomic status (education and income) were measured at baseline. Negative affect and CMC were measured at baseline (1995) and end of follow up (2004). Race was the moderator. Linear regression was used to test the moderating effect of race on the reciprocal associations between CMC and negative affect, net of covariates. In the pooled sample, while baseline CMC was predictive of an increase in negative affect over time, baseline negative affect was also predictive of an increase in CMC. We found interactions between race and baseline CMC on change in depressive symptoms, as well as race with negative affect on CMC change, suggesting that the associations between CMC and negative affect are stronger for Whites in comparison to Blacks. Blacks and Whites differ in reciprocal links between CMC and negative affect over time. This finding replicates recent studies on differential links between psychosocial factors and physical health based on race. Findings may help us better understand how Black-White health paradox develops across mid and later life.

  4. Reciprocal translocation of small numbers of inbred individuals rescues immunogenetic diversity.

    Science.gov (United States)

    Grueber, Catherine E; Sutton, Jolene T; Heber, Sol; Briskie, James V; Jamieson, Ian G; Robertson, Bruce C

    2017-05-01

    Genetic rescue can reduce inbreeding depression and increase fitness of small populations, even when the donor populations are highly inbred. In a recent experiment involving two inbred island populations of the New Zealand South Island robin, Petroica australis, reciprocal translocations improved microsatellite diversity and individual fitness. While microsatellite loci may reflect patterns of genome-wide diversity, they generally do not indicate the specific genetic regions responsible for increased fitness. We tested the effectiveness of this reciprocal translocation for rescuing diversity of two immunogenetic regions: Toll-like receptor (TLR) and major histocompatibility complex (MHC) genes. We found that the relatively small number of migrants (seven and ten per island) effectively brought the characteristic TLR gene diversity of each source population into the recipient population. However, when migrants transmitted TLR alleles that were already present at high frequency in the recipient population, it was possible for offspring of mixed heritage to have decreased gene diversity compared to recipient population diversity prior to translocation. In contrast to TLRs, we did not observe substantial changes in MHC allelic diversity following translocation, with limited evidence of a decrease in differentiation, perhaps because most MHC alleles were observed at both sites prior to the translocation. Overall, we conclude that small numbers of migrants may successfully restore the diversity of immunogenetic loci with few alleles, but that translocating larger numbers of animals would provide additional opportunity for the genetic rescue of highly polymorphic immunity regions, such as the MHC, even when the source population is inbred. © 2017 John Wiley & Sons Ltd.

  5. Frequency standards

    CERN Document Server

    Riehle, Fritz

    2006-01-01

    Of all measurement units, frequency is the one that may be determined with the highest degree of accuracy. It equally allows precise measurements of other physical and technical quantities, whenever they can be measured in terms of frequency.This volume covers the central methods and techniques relevant for frequency standards developed in physics, electronics, quantum electronics, and statistics. After a review of the basic principles, the book looks at the realisation of commonly used components. It then continues with the description and characterisation of important frequency standards

  6. [The reciprocity rule in the construction of relationships as the key in relational processes].

    Science.gov (United States)

    Fenelli, Antonio; Volpi, Cecilia; Guarracino, Emanuele; Galli, Virginia; Esposito, Massimo

    2011-01-01

    Reciprocity as an expression of the therapist-patient relationship is pointed-out by Mario Reda who refers to Comparetti's studies on the mother-foetus reciprocity, mediated by the so-called "jumps". Reciprocal behaviours are clearly observable during bird and other animal courtship behaviour, whereas in the Sapiens sapiens species, we may observe the establishing of a very complex reciprocity system, which starts with gestures and bodily attitudes, subsequently activating sensory-motor emotional schemata and internal working models, thus enabling the construction of personal meanings. A relationship may result from an encounter provided that "compatible" meanings are constructed in the context of "possible reciprocity" of significant systems. The observation of reciprocity provides a concrete possibility to reduce the risk of absolute subjectivity related to the I or the you, superceding it through the us.

  7. Modeling of nonlinear responses for reciprocal transducers involving polarization switching

    DEFF Research Database (Denmark)

    Willatzen, Morten; Wang, Linxiang

    2007-01-01

    Nonlinearities and hysteresis effects in a reciprocal PZT transducer are examined by use of a dynamical mathematical model on the basis of phase-transition theory. In particular, we consider the perovskite piezoelectric ceramic in which the polarization process in the material can be modeled...... by Landau theory for the first-order phase transformation, in which each polarization state is associated with a minimum of the Landau free-energy function. Nonlinear constitutive laws are obtained by using thermodynamical equilibrium conditions, and hysteretic behavior of the material can be modeled...

  8. Reciprocity within the framework of nuclear civil liability law

    International Nuclear Information System (INIS)

    Feldmann, F.J.

    1986-01-01

    With regard to reciprocity in international and national nuclear liability law, the Federal Republic of Germany attaches great importance to that principle, especially under the following three aspects: 1.) Application of the international conventions in national law, irrespective of their internationally binding nature, 2.) application of the international conventions in relations with non-convention states in cases of damage, 3.) application of supplementary national nuclear liability law in relations with convention as well as non-convention states in cases of damage. (CW) [de

  9. The reciprocal relationship between sexual victimization and sexual assertiveness.

    Science.gov (United States)

    Livingston, Jennifer A; Testa, Maria; VanZile-Tamsen, Carol

    2007-03-01

    Low sexual assertiveness has been proposed as a possible mechanism through which sexual revictimization occurs, yet evidence for this has been mixed. In this study, prospective path analysis was used to examine the relationship between sexual refusal assertiveness and sexual victimization over time among a community sample of women. Results provide support for a reciprocal relationship, with historical victimization predicting low sexual assertiveness and low sexual assertiveness predicting subsequent victimization. The effect of recent sexual victimization on subsequent sexual assertiveness also was replicated prospectively. These findings suggest that strengthening sexual assertiveness may help reduce vulnerability to future victimization.

  10. Subjective performance evaluations and reciprocity in principal-agent relations

    DEFF Research Database (Denmark)

    Sebald, Alexander Christopher; Walzl, Markus

    2014-01-01

    . In contrast to existing models of reciprocity, we find that agents tend to sanction whenever the feedback of principals is below their subjective self-evaluations even if agents' pay-offs are independent of it. In turn, principals provide more positive feedback (relative to their actual performance assessment......We conduct a laboratory experiment with agents working on, and principals benefiting from, a real effort task in which the agents' performance can only be evaluated subjectively. Principals give subjective performance feedback to agents, and agents have an opportunity to sanction principals...

  11. Optimal contracts based on subjective performance evaluations and reciprocity

    DEFF Research Database (Denmark)

    Sebald, Alexander Christopher; Walzl, Markus

    2015-01-01

    As demonstrated in a recent laboratory experiment (see Sebald & Walzl, 2014), individuals tend to sanction others who subjectively evaluate their performance whenever this assessment falls short of the individuals’ self-evaluation. Interestingly, this is the case even if the individuals’ earnings...... are unaffected by the subjective performance appraisal. Hence, performance feedback which falls short of agents’ self- evaluations can be interpreted as an unkind act that triggers a negatively reciprocal response not only if the assessment determines agents’ earnings but also when it lacks monetary consequences...

  12. Reciprocity in nuclear third-party liability law

    International Nuclear Information System (INIS)

    Moser, B.

    1992-01-01

    The Pariser Convention, with its additional protocols, offers a substantial simplification of that part of nuclear law relating to international private and procedural law. This concerns, inter alia, the maximum ceiling of liability of a nuclear operator for damage caused by a nuclear incident. The paper presents in detail how the legislation of various contracting Parties to the Paris Convention and noncontracting parties deals with the question of reciprocity in nuclear civil liability and procedural law. The Vienna Convention on liability for nuclear damages of 1963, which is international private and procedural law. (orig./HSCH) [de

  13. Three-dimensional Reciprocal Structures: Morphology, Concepts, Generative Rules

    DEFF Research Database (Denmark)

    Parigi, Dario; Pugnale, Alberto

    2012-01-01

    This paper present seven different three dimensional structures based on the principle of structural reciprocity with superimposition joint and standardized un-notched elements. Such typology could be regarded as being intrinsically three-dimensional because elements sit one of the top of the oth......, causing every configuration to develop naturally out-of the plane. The structures presented here were developed and built by the students of the Master of Science in “Architectural Design” during a two week long workshop organized at Aalborg University in the fall semester 2011....

  14. A DISCUSSIN OVER RECIPROCITY PRINCIPLE’S AFFECT ON SOCIAL CAPITAL’S PROLIFICACY

    OpenAIRE

    Mustafa Latif Emek

    2014-01-01

    In this study two concepts, social capital and reciprocity principles, have been introduced and their reciprocal relationship and affects also been discussed. Social Capital, an indispensable notion for the development of society from all aspects has a close relationship with reciprocity principle which regulates and forms relationship webs. In this study we firstly examined both from emergence point and sources of social capital concept which can also be entitled as social webs. Afterward...

  15. Advances in Design and Fabrication of Free-Form Reciprocal Structures

    DEFF Research Database (Denmark)

    Parigi, Dario

    2016-01-01

    The paper presents the advances in design and fabrication of free-form Reciprocal Structures, and their application a during a one-week long workshop with the students of the 1st semester of the Master of Science in Architecture and Design, fall 2015, at Aalborg University. Two new factors were...... introduced and tested: a new version of the software Reciprocalizer, and an evolution of the Reciprocalizer Robot. The workshop didactic framework Performance Aided/Assisted Design (PAD) is presented....

  16. Frequency Synthesiser

    NARCIS (Netherlands)

    Drago, Salvatore; Sebastiano, Fabio; Leenaerts, Dominicus M.W.; Breems, Lucien J.; Nauta, Bram

    2016-01-01

    A low power frequency synthesiser circuit (30) for a radio transceiver, the synthesiser circuit comprising: a digital controlled oscillator configured to generate an output signal having a frequency controlled by an input digital control word (DCW); a feedback loop connected between an output and an

  17. Frequency synthesiser

    NARCIS (Netherlands)

    Drago, S.; Sebastiano, Fabio; Leenaerts, Dominicus Martinus Wilhelmus; Breems, Lucien Johannes; Nauta, Bram

    2010-01-01

    A low power frequency synthesiser circuit (30) for a radio transceiver, the synthesiser circuit comprising: a digital controlled oscillator configured to generate an output signal having a frequency controlled by an input digital control word (DCW); a feedback loop connected between an output and an

  18. The influence of reciprocating sliding wear on the oxidation behaviour of Fe-12Cr steel

    International Nuclear Information System (INIS)

    Smith, A.F.

    1989-01-01

    Medium-chromium ferritic alloys are used extensively in advanced gas cooled reactors (AGRs). Under certain conditions these alloys can undergo breakaway oxidation in which the rate-limiting step is located at the oxide/metal interface rather than the more usual gas/oxide interface; this results in linear oxidation kinetics. Repeated removal of oxide layers can expose chromium-depleted metal to the oxidizing gas and promote nucleation of breakaway oxidation. The question has been addressed as to whether high temperature sliding wear processes can also disrupt the surface so as to make the material potentially susceptible to breakaway oxidation. High temperature reciprocating wear tests of Fe-12Cr material in both low and high pressure reactor gas have been carried out. As expected, compact adhesive load-bearing oxide and mixed oxide/metal beds form in wear regions. These contacting features wear at very low rates of less than 10 -16 m 3 (Nm) -1 . Preformed oxides wear at sufficiently low rates at high temperature as to preclude the possibility of exposure of the underlying metal to the reactor gas. It is thus unlikely that sliding wear processes will accelerate the tendency for initiation of breakaway oxidation. (author)

  19. Embryological studies of reciprocal crosses between Vicia faba and Vicia narbonensis

    Directory of Open Access Journals (Sweden)

    Maciej Zenkteler

    2014-01-01

    Full Text Available A study was undertaken to asses the reciprocal crossability between Vicia faba and Vicia narbonensis. Flower buds or only ovaries of several varietes and genotypes were cross-pollinated in vivo (green house and field and in vitro. Only few pollen tubes passed the style and entered into the ovary. On the whole number of 5320 cross pollinated in vivo and in vitro flowers and ovaries of Vicia narbonensis only 78 globular hybrid embryos were observed. After cross pollination in vivo of 3860 flower buds and ovaries of Vicia faba globular embryos developed in 124 ovules. The highest number of globular embryos were obtained when the Vicia faba line 1/33 was pollinated with Vicia narbonensis lines P3, P5, 150, SE.Embryogenesis proceeded till the 6-10 day after pollination, however, karyological disturbances in the cells of embryos and endosperm were often noticed at earlier stages. In vitro pollen grains of Vicia faba germinated on stigmas and ovaries of Vicia narbonensis, a significant increase in the growth of pollen tubes was noticed after ovary pollination. The technique of in vitro pollination was not suitable for Vicia faba as the inoculated explants died shortly after transferring onto the medium. The results indicate that finding a more suitable genotype for crossing may give a chance to obtain higher number of embryos (example line 1/33 - thus sufficient number for culturing them on media.

  20. Model of Wikipedia growth based on information exchange via reciprocal arcs

    Science.gov (United States)

    Zlatić, V.; Štefančić, H.

    2011-03-01

    We show how reciprocal arcs significantly influence the structural organization of Wikipedias, online encyclopedias. It is shown that random addition of reciprocal arcs in the static network cannot explain the observed reciprocity of Wikipedias. A model of Wikipedia growth based on preferential attachment and on information exchange via reciprocal arcs is presented. An excellent agreement between in-degree distributions of our model and real Wikipedia networks is achieved without fitting the distributions, but by merely extracting a small number of model parameters from the measurement of real networks.

  1. Peltier cooling and onsager reciprocity in ferromagnetic thin films.

    Science.gov (United States)

    Avery, A D; Zink, B L

    2013-09-20

    We present direct measurements of the Peltier effect as a function of temperature from 77 to 325 K in Ni, Ni(80)Fe(20), and Fe thin films made using a suspended Si-N membrane structure. Measurement of the Seebeck effect in the same films allows us to directly test predictions of Onsager reciprocity between the Peltier and Seebeck effects. The Peltier coefficient Π is negative for both Ni and Ni(80)Fe(20) films and positive for the Fe film. The Fe film also exhibits a peak associated with the magnon drag Peltier effect. The observation of magnon drag in the Fe film verifies that the coupling between the phonon, magnon, and electron systems in the film is the same whether driven by heat current or charge current. The excellent agreement between Π values predicted using the experimentally determined Seebeck coefficient for these films and measured values offers direct experimental confirmation of the Onsager reciprocity between these thermoelectric effects in ferromagnetic thin films near room temperature.

  2. Recent Russian-Hanford MPC and A reciprocal exchanges

    International Nuclear Information System (INIS)

    Sorenson, R.J.; Schlegel, S.C.; Vogt, E.C.; Six, D.E.

    1995-01-01

    As part of the 1993 US/Russian Government-to-Government Nuclear Material Protection, Control, and Accounting (MPC and A) initiative, the US government has proposed a series of site visits to both countries to address nonproliferation concerns and to reduce the potential theft or diversion of direct-use materials in Russia. In 1994, four exchange visits were made between the Hanford Site, which is located in Richland, Washington, and the Mayak and Tomsk Sites in Russia. The two Hanford visits were historical in the sense that no Russians had previously been inside a plutonium storage facility in the United States. The reciprocal visit to the Mayak nuclear complex in Russia provided the US delegation with numerous insights to these facilities and their respective safeguards programs. The reciprocal visit to the Tomsk Site in central Siberia provided the US participants with many insights to the issues surrounding the cutoff of plutonium production and storage of plutonium. This paper describes the specific activities undertaken by exchange participants during the visits. In addition, several conclusions regarding the overall US/Russian exchange program are provided

  3. Earning points for moral behavior: organ allocation based on reciprocity.

    Science.gov (United States)

    Ravelingien, An; Krom, Andre

    2005-01-01

    Anticipating the reevaluation of the Dutch organ procurement system, in late 2003 the Rathenau Institute published a study entitled 'Gift or Contribution?' In this study, the author, Govert den Hartogh, carries out a thorough moral analysis of the problem of organ shortage and fair allocation of organs. He suggests there should be a change in mentality whereby organ donation is no longer viewed in terms of charity and the volunteer spirit, but rather in terms of duty and reciprocity. The procurement and allocation of donor organs should be seen as a system of mutually assured help. Fair allocation would imply to give priority to those who recognize and comply with their duty: the registered donors. The idea of viewing organ donation as an undertaking involving mutual benefit rather than as a matter of charity, however, is not new. Notwithstanding the fact that reference to charity and altruism is not required in order for the organ donation to be of moral significance, we will argue against the reciprocity-based scenario. Steering organ allocation towards those who are themselves willing to donate organs is both an ineffective and morally questionable means of attempting to counter organ shortage.

  4. The Role of Reciprocity in Verbally Persuasive Robots.

    Science.gov (United States)

    Lee, Seungcheol Austin; Liang, Yuhua Jake

    2016-08-01

    The current research examines the persuasive effects of reciprocity in the context of human-robot interaction. This is an important theoretical and practical extension of persuasive robotics by testing (1) if robots can utilize verbal requests and (2) if robots can utilize persuasive mechanisms (e.g., reciprocity) to gain human compliance. Participants played a trivia game with a robot teammate. The ostensibly autonomous robot helped (or failed to help) the participants by providing the correct (vs. incorrect) trivia answers. Then, the robot directly asked participants to complete a 15-minute task for pattern recognition. Compared to no help, results showed that a robot's prior helping behavior significantly increased the likelihood of compliance (60 percent vs. 33 percent). Interestingly, participants' evaluations toward the robot (i.e., competence, warmth, and trustworthiness) did not predict compliance. These results also provided an insightful comparison showing that participants complied at similar rates with the robot and with computer agents. This result documents a clear empirically powerful potential for the role of verbal messages in persuasive robotics.

  5. Modeling of flexible reciprocating compressor considering the crosshead subsidence

    Science.gov (United States)

    Xue, Xiaogang; Liu, Shulin; Sun, Xin

    2018-01-01

    Crank-slider mechanisms are important parts of heavy duty machines, including reciprocating compressors, combustion motors. This paper targets on the dynamic response of the crosshead in a reciprocating compressor, taking into consideration the crosshead deviation from the original level. The traditional model of the compressor is usually a slider-mechanism system without considering the deflection of the crosshead, thus neglecting the influence of the piston rod, which has some flexible features. In this paper, a rigid-flexible model of slider-crank is described theoretically, using the commercial software MATLAB, where the crank, connecting rod and crosshead are treated as rigid bodies, while the piston rod connected to the crosshead is considered as a flexible body. The dynamic response of the mechanism with the crosshead subsidence is discussed detailedly in this paper. After calculated theoretically, the MATLAB simulation showed that the dynamic response of the crosshead will be greatly influenced if the crosshead subsided from the original level. Also, the influence of the crosshead subsidence was also investigated, and some extra vibration of the crosshead arises.

  6. Complementary coordination strategies in a joint Fitts’ reciprocal aiming task

    DEFF Research Database (Denmark)

    Konvalinka, Ivana; Skewes, Lea; Michael, J.

    How do dyads coordinate their actions to achieve a common goal when one person has the more difficult task? In the present study, dyads were instructed to engage in a Fitts’s reciprocal aiming task as accurately as possible, and at a given tempo sent through their headphones. They were in conditi......How do dyads coordinate their actions to achieve a common goal when one person has the more difficult task? In the present study, dyads were instructed to engage in a Fitts’s reciprocal aiming task as accurately as possible, and at a given tempo sent through their headphones. They were...... in conditions where they either received auditory feedback of 1) SELF-generated taps, 2) taps generated by the OTHER co-actor, or 3) regular, COMPUTER-generated taps. In conditions 2) and 3), they were also instructed to synchronize with their feedback as best as possible. In each trial, each participant...... a joint goal, by taking on leader-follower roles....

  7. Cost comparison of natural-gas reciprocating engines and electric motors in variable-load industrial applications. Topical report Dec 84-Mar 85

    Energy Technology Data Exchange (ETDEWEB)

    Chockie, A.D.

    1985-03-01

    This report compares natural gas-fired reciprocating engines and electrical motors, with and without variable-frequency speed controller, for one such industrial application. Two types of engines, with and without heat recovery, and three types of motors, standard, high efficiency, and high efficiency with variable-frequency speed controller, are considered. The total life-cycle costs of these five prime movers are compared for three scenarios with varying extent of part-load operations. The relative importance of each cost component is evaluated based on this comparison. The effect of engine heat utilization is addressed parametrically to demonstrate this additional benefit from gas prime movers.

  8. Manipulating light at nanoscale: Non-reciprocal, dynamic and active plasmonic effects

    Science.gov (United States)

    Yu, Zongfu

    -band, and non-reciprocal isolation can be accomplished by spatial-temporal refractive index modulations. We further show in Chapter 5 that using photonic transitions, a high-Q integrated cavity can be created dynamically, with both quality factor and resonant frequency independently tunable. In the last part of the thesis, we propose to exploit the unique properties of surface plasmons to enhance the signal-to-noise ratio of mid-infrared photodetectors. The proposed photodetector consists of a slit in a metallic slab filled with absorptive semiconductor material. Light absorption in the slit is enhanced due to Fabry-Perot resonances. Further absorption enhancement is achieved by surrounding the slit with a series of periodic grooves that enable the excitation of surface plasmons that carry electromagnetic energy towards the slit. Using surface plasmonic waveguides, we also show in Chapter 7 that the incorporation of gain media in only a selected device area can annul the effect of material loss, and enhance the performance of loss-limited plasmonic devices. In addition, we demonstrate that optical gain provides a mechanism for on/off switching in metal-dielectric-metal plasmonic waveguides.

  9. Propagation of monochromatic light in a hot and dense medium

    Science.gov (United States)

    Masood, Samina S.

    2017-12-01

    Photons, as quanta of electromagnetic fields, determine the electromagnetic properties of an extremely hot and dense medium. Considering the properties of the photons in the interacting medium of charged particles, we explicitly calculate the electromagnetic properties such as the electric permittivity, magnetic permeability, refractive index and the propagation speed of electromagnetic signals in an extremely hot and dense background. Photons acquire a dynamically generated mass in such a medium. The screening mass of the photon, the Debye shielding length and the plasma frequency are calculated as functions of the statistical parameters of the medium. We study the properties of the propagating particles in astrophysical systems of distinct statistical conditions. The modifications in the properties of the medium lead to the equation of state of the system. We mainly calculate all these parameters for extremely high temperatures of the early universe.

  10. Propagation of monochromatic light in a hot and dense medium

    Energy Technology Data Exchange (ETDEWEB)

    Masood, Samina S. [University of Houston Clear Lake, Department of Physical and Applied Sciences, Houston, TX (United States)

    2017-12-15

    Photons, as quanta of electromagnetic fields, determine the electromagnetic properties of an extremely hot and dense medium. Considering the properties of the photons in the interacting medium of charged particles, we explicitly calculate the electromagnetic properties such as the electric permittivity, magnetic permeability, refractive index and the propagation speed of electromagnetic signals in an extremely hot and dense background. Photons acquire a dynamically generated mass in such a medium. The screening mass of the photon, the Debye shielding length and the plasma frequency are calculated as functions of the statistical parameters of the medium. We study the properties of the propagating particles in astrophysical systems of distinct statistical conditions. The modifications in the properties of the medium lead to the equation of state of the system. We mainly calculate all these parameters for extremely high temperatures of the early universe. (orig.)

  11. Birefringence in a chiral medium, via temporal cloaking

    Science.gov (United States)

    Khan, Humayun; Haneef, Muhammad

    2017-05-01

    This paper reports theoretical investigation of birefringence in a chiral medium for the creation of temporal cloaking. The chiral medium splits the input probe beam into left/right circular polarized beams. These left/right circular polarized beams are then controlled and modified within the chiral medium. The left circular polarized beam delays by 24 ns whereas the right circular polarized beam advances by  -23 ns at a control field of rabbi frequency 6γ . This opens a 47 ns time gap for temporal cloaking to hide information without noise corruption and energy loss. The results have potential applications in communication devices for secure propagation of light pulse.

  12. Open waveguide cavity using a negative index medium.

    Science.gov (United States)

    Yan, Wei; Shen, Linfang

    2008-12-01

    An open waveguide cavity formed by a pair of planar waveguides, in which one guiding layer is a negative index medium and the other is a positive index medium, is theoretically demonstrated. For such a waveguide cavity the resonant frequency is independent of the total length of the waveguide system. With the coupled mode theory it is shown that energy flow circulation can be established through the special coupling between the waveguides at the resonant frequency, and thus the wave fields are localized. This phenomenon is further verified numerically with the finite-difference time-domain method. The quality factor of the open waveguide cavity is also discussed.

  13. Investigating Reciprocal Meaning-Making as an Element of Intercultural Language Learning in the Languages Classroom

    Science.gov (United States)

    Skene, Catherine

    2013-01-01

    The "Australian Curriculum: Languages" is based on an intercultural orientation to the teaching and learning of languages. Reciprocal meaning-making, or interpreting self in relation to others as language users, is a key element in an intercultural orientation. The concept of reciprocating is embedded in the language-specific curricula…

  14. Teaching Reciprocal Space to Undergraduates via Theory and Code Components of an IPython Notebook

    Science.gov (United States)

    Srnec, Matthew N.; Upadhyay, Shiv; Madura, Jeffrey D.

    2016-01-01

    In this technology report, a tool is provided for teaching reciprocal space to undergraduates in physical chemistry and materials science courses. Reciprocal space plays a vital role in understanding a material's electronic structure and physical properties. Here, we provide an example based on previous work in the "Journal of Chemical…

  15. Children's Understanding of Indebtedness as a Feature of Reciprocal Help Exchanges between Peers.

    Science.gov (United States)

    De Cooke, Peggy A.

    1992-01-01

    Studied 120 children's understanding of indebtedness. Fifth graders reported a diminished obligation to reciprocate help that was given at a low cost to the helper; the obligation remained high for first and third graders. All children reported more obligation to reciprocate help from acquaintances than help from friends. (LB)

  16. Talking about Service-Learning: Product or Process? Reciprocity or Solidarity?

    Science.gov (United States)

    Clifford, Joan

    2017-01-01

    Through an exploration of values of the neoliberal university and critical service-learning, this article explores how associating service-learning with products and relationships based on reciprocity negatively impacts its connection to social justice. By emphasizing the constructs of process and solidarity, instead of products and reciprocity,…

  17. 76 FR 12863 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2011-03-09

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines... combustion engines. The final rule was published on August 20, 2010. This direct final action amends certain... Emission Standards for Hazardous Air Pollutant for Stationary Reciprocating Internal Combustion Engines...

  18. 78 FR 6673 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2013-01-30

    ... and 63 National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New Source Performance Standards for Stationary Internal Combustion Engines; Final Rule #0;#0... Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New Source...

  19. Measuring reciprocity in high functioning children and adolescents with autism spectrum disorders

    NARCIS (Netherlands)

    Backer van Ommeren, C.; Begeer, S.; Scheeren, A.M.; Koot, H.M.

    2012-01-01

    Few instruments have been developed that measure impairments in reciprocity, a defining feature of autism. We introduce a new test assessing the quality of reciprocal behaviour: the interactive drawing test (IDT). Children and adolescents (n = 49) with and without high functioning autism spectrum

  20. The Reciprocal Internal/External Frame of Reference Model Using Grades and Test Scores

    Science.gov (United States)

    Möller, Jens; Zimmermann, Friederike; Köller, Olaf

    2014-01-01

    Background: The reciprocal I/E model (RI/EM) combines the internal/external frame of reference model (I/EM) with the reciprocal effects model (REM). The RI/EM extends the I/EM longitudinally and the REM across domains. The model predicts that, within domains, mathematics and verbal achievement (VACH) and academic self-concept have positive effects…

  1. The Reciprocal Effects Model Revisited: Extending Its Reach to Gifted Students Attending Academically Selective Schools

    Science.gov (United States)

    Seaton, Marjorie; Marsh, Herbert W.; Parker, Philip D.; Craven, Rhonda G.; Yeung, Alexander S.

    2015-01-01

    The reciprocal effects model (REM) predicts a reciprocal relation between academic self-concept and academic achievement, whereby prior academic self-concept is associated with future gains in achievement, and prior achievement is related to subsequent academic self-concept. Although research in this area has been extensive, there has been a…

  2. Socrates, Augustine, and Paul Gauguin on the Reciprocity between Speech and Silence in Education

    Science.gov (United States)

    Caranfa, Angelo

    2013-01-01

    While most educational practices today place an excessive amount of attention on discourse, this article attaches great importance to the reciprocity between speech and silence by drawing from the writings of Plato's Socrates, Augustine, and Paul Gauguin for whom this reciprocity is of the essence in learning. These three figures teach that…

  3. Reciprocity in Online Markets: Empirical Studies of Auction and Barter Markets

    Science.gov (United States)

    Ye, Shun

    2013-01-01

    My dissertation seeks to understand how reciprocity affects transaction outcomes and mechanism design in online markets. The first essay examines negative reciprocity illustrated as feedback-revoking behavior in the eBay auction market, focusing on its impact and implications for reputation system design. I utilize the biggest policy change of…

  4. 14 CFR 135.377 - Large transport category airplanes: Reciprocating engine powered: Landing limitations: Alternate...

    Science.gov (United States)

    2010-01-01

    ...: Reciprocating engine powered: Landing limitations: Alternate airports. 135.377 Section 135.377 Aeronautics and... Limitations § 135.377 Large transport category airplanes: Reciprocating engine powered: Landing limitations: Alternate airports. No person may list an airport as an alternate airport in a flight plan unless the...

  5. Confession and Carrying into Execution of Foreign Arbitration Courts' Decisions: Reciprocity and Public Policy

    Science.gov (United States)

    Sarina, Salima A.; Nukusheva, Aigul A.; Kalmagambetov, Kassym S.; Kumysbekova, Zhanara T.; Nesterova, Elena V.

    2016-01-01

    The article contains a comparative analysis of foreign arbitration courts' decisions, ensuring the reciprocity and public policy. The aim of the study is to explore such aspects as reciprocity and public policy of arbitration courts. The result is the view of the public policy, despite its apparent irrelevance in today's Kazakhstan, which is of…

  6. PERCEIVED RECIPROCITY, SOCIAL SUPPORT, AND STRESS AT WORK - THE ROLE OF EXCHANGE AND COMMUNAL ORIENTATION

    NARCIS (Netherlands)

    BUUNK, BP; DOOSJE, BJ; Jans, G.J.M.; HOPSTAKEN, LEM

    1993-01-01

    Perceived reciprocity regarding support in relationships at work was examined among employees of a psychiatric hospital (Study 1) and in a study of employees of the Dutch National Railway Company (Study 2). Relationships with colleagues were more often perceived as reciprocal than relationships with

  7. Apically extruded dentin debris by reciprocating single-file and multi-file rotary system.

    Science.gov (United States)

    De-Deus, Gustavo; Neves, Aline; Silva, Emmanuel João; Mendonça, Thais Accorsi; Lourenço, Caroline; Calixto, Camila; Lima, Edson Jorge Moreira

    2015-03-01

    This study aims to evaluate the apical extrusion of debris by the two reciprocating single-file systems: WaveOne and Reciproc. Conventional multi-file rotary system was used as a reference for comparison. The hypotheses tested were (i) the reciprocating single-file systems extrude more than conventional multi-file rotary system and (ii) the reciprocating single-file systems extrude similar amounts of dentin debris. After solid selection criteria, 80 mesial roots of lower molars were included in the present study. The use of four different instrumentation techniques resulted in four groups (n = 20): G1 (hand-file technique), G2 (ProTaper), G3 (WaveOne), and G4 (Reciproc). The apparatus used to evaluate the collection of apically extruded debris was typical double-chamber collector. Statistical analysis was performed for multiple comparisons. No significant difference was found in the amount of the debris extruded between the two reciprocating systems. In contrast, conventional multi-file rotary system group extruded significantly more debris than both reciprocating groups. Hand instrumentation group extruded significantly more debris than all other groups. The present results yielded favorable input for both reciprocation single-file systems, inasmuch as they showed an improved control of apically extruded debris. Apical extrusion of debris has been studied extensively because of its clinical relevance, particularly since it may cause flare-ups, originated by the introduction of bacteria, pulpal tissue, and irrigating solutions into the periapical tissues.

  8. A note on number fields having reciprocal integer generators | Zaïmi ...

    African Journals Online (AJOL)

    We prove that a totally complex algebraic number field K; having a conjugate which is not closed under complex conjugation, can be generated by a reciprocal integer, when the Galois group of its normal closure is contained in the hyperoctahedral group Bdeg(K)/2. Keywords: Reciprocal integers, unit primitive elements, ...

  9. Development and verification of a reciprocating test rig designed for investigation of piston ring tribology

    DEFF Research Database (Denmark)

    Pedersen, Michael Torben; Imran, Tajammal; Klit, Peder

    2009-01-01

    This paper describes the development and verification of a reciprocating test rig, which was designed to study the piston ring tribology. A crank mechanism is used to generate a reciprocating motion for a moving plate, which acts as the liner. A stationary block acting as the ring package is loaded......, which is suitable for the study of piston ring tribology....

  10. Reciprocal Teaching and Emotional Intelligence: A Study of Iranian EFL Learners' Reading Comprehension

    Science.gov (United States)

    Izadi, Mehri; Nowrouzi, Hossein

    2016-01-01

    The present study aimed at exploring the effect of reciprocal reading strategies instruction on reading comprehension of EFL learners. Emotional intelligence, another variable of interest, was assessed to indicate whether it plays a role in learners' comprehension. In a pre- and post-test study, forty-two learners went through a reciprocal reading…

  11. Using Excel's Solver Function to Facilitate Reciprocal Service Department Cost Allocations

    Science.gov (United States)

    Leese, Wallace R.

    2013-01-01

    The reciprocal method of service department cost allocation requires linear equations to be solved simultaneously. These computations are often so complex as to cause the abandonment of the reciprocal method in favor of the less sophisticated and theoretically incorrect direct or step-down methods. This article illustrates how Excel's Solver…

  12. Commitments and reciprocity in trust situations : Experimental studies on obligation, indignation, and self-consistency

    NARCIS (Netherlands)

    Vieth, M.D.

    2009-01-01

    Explaining social order is of primary concern for social theories. It requires the study of sanctioning mechanisms that help enforce social norms. Punishment for misbehavior and reward for good conduct are forms of reciprocity. Reciprocal behavior can be rooted in emotions that constitute the basis

  13. Social ties and coordination on negative reciprocity: The role of affect

    NARCIS (Netherlands)

    Reuben, E.; van Winden, F.

    2008-01-01

    This is an experimental study of negative reciprocity in the case of multiple reciprocators. We use a three-player power-to-take game where a proposer is matched with two responders. We compare a treatment in which responders are anonymous to each other (strangers) with one in which responders know

  14. Commitments and Reciprocity in Trust Situations : Experimental Studies on Obligation, Indignation, and Self-Consistency.

    NARCIS (Netherlands)

    Vieth, Manuela

    2009-01-01

    Explaining social order is of primary concern for social theories. It requires the study of sanctioning mechanisms that help enforce social norms. Punishment for misbehavior and reward for good conduct are forms of reciprocity. Reciprocal behavior can be rooted in emotions that constitute the basis

  15. Naturalization, reciprocity and marks of marital violence: male defendants' perceptions

    Directory of Open Access Journals (Sweden)

    Gilvânia Patrícia do Nascimento Paixão

    Full Text Available ABSTRACT Objective: to analyze male criminals' perception about marital violence. Method: An exploratory, descriptive, qualitative study undertaken with 23 men who were criminally prosecuted for marital violence. A multimethod data collection was conducted, with individual interview and focal group techniques combined, between May and December 2015. The data collected were initially categorized using the NVIVO® 11 software program, and then organized using the Collective Subject Discourse method. Results: the collective discourses reveal that, in the male's perception, conjugal violence is inherent in a marital relationships: it is a private, reciprocal problem that leaves body marks. Conclusion: gender dissymmetry as a social construct is evidenced, signaling the need to create spaces for reflection and re-signification of men and women, from a gender perspective.

  16. Revising Sangiovanni's reciprocity-based internationalism: towards international egalitarian obligations

    Directory of Open Access Journals (Sweden)

    Conor Heaney

    2016-06-01

    Full Text Available To whom do we owe obligations of socio-economic justice? How are such obligations generated? Internationalism denotes a range of approaches to these questions. This paper examines Andrea Sangiovanni's—an internationalist—response to these questions. Sangiovanni argues that we owe egalitarian obligations only to those in the state, and that egalitarian obligations are generated through relationships of ‘reciprocity’. His is a ‘reciprocity-based internationalism’ (RBI. RBI has two components—one normative and another empirical. In this paper, I will assume the normative component, but reject its empirical component. My rejection of the empirical component has normative implications for RBI, which generate egalitarian obligations beyond the state. In other words, my revision of RBI is an argument in favour of international egalitarian obligations not generated through cosmopolitanism, but through internationalism.

  17. Obtaining local reciprocal lattice vectors from finite-element analysis.

    Science.gov (United States)

    Sutter, John P; Connolley, Thomas; Hill, Tim P; Huang, Houcheng; Sharp, Doug W; Drakopoulos, Michael

    2008-11-01

    Finite-element analysis is frequently used by engineers at synchrotron beamlines to calculate the elastic deformation of a single crystal undergoing mechanical bending or thermal load. ANSYS Workbench software is widely used for such simulations. However, although ANSYS Workbench software provides useful information on the displacements, strains and stresses within the crystal, it does not yield the local reciprocal lattice vectors that would be required for X-ray diffraction calculations. To bridge this gap, a method based on the shape functions and interpolation procedures of the software itself has been developed. An application to the double-crystal bent Laue monochromator being designed for the I12 (JEEP) wiggler beamline at the Diamond Light Source is presented.

  18. Up-regulation of reciprocal inhibition by explosive strength training

    DEFF Research Database (Denmark)

    Geertsen, Svend Sparre; Jensen, Jesper Lundbye; Nielsen, Jens Bo

    At the onset of dorsiflexion disynaptic reciprocal inhibition (DRI) of soleus motoneurones is increased in order to prevent activation of the antagonistic plantarflexors. This is caused by descending facilitation of transmission in the DRI pathway. Since the risk of eliciting stretch reflexes...... in the ankle plantarflexors at the onset of dorsiflexion is larger the quicker the movement, we hypothesized that DRI may be up-regulated when subjects are trained to perform dorsiflexion movements as quickly as possible.   For this purpose, 15 healthy human subjects (7 male, 8 female) with an average age...... by 6% before the training and by 22% after the training, which was a statistically significant difference (pregulated in healthy subjects following explosive strength training in order to ensure efficient suppression of the antagonist...

  19. Power relations and reciprocity: dialectics of knowledge construction.

    Science.gov (United States)

    Ben-Ari, Adital; Enosh, Guy

    2013-03-01

    In this article we suggest a theoretical framework of knowledge construction by employing the concept of dialectics to power relationships between researcher and participants. Power distribution in research is perceived as dichotomous and asymmetrical in favor of the researcher, creating unequal power relations that make exploitation possible. Acknowledging such exploitation has led to a critical stance and attempts to bridge gaps through egalitarianism and empowerment of participants. Some scholars have focused on shifting expert knowledge differentials between researcher and participants throughout the research project. Others have evaluated such gaps as a source of knowledge construction. In the present work we applied a dialectical approach to understanding research relationships, suggesting reciprocity as their defining attribute, regardless of symmetry or asymmetry and as a source of knowledge construction. In this article we recommend avoiding a taken-for-granted attitude, because we see it as a direct obstacle to the construction of knowledge.

  20. Prostaglandins release plasma 'reciprocal coupling factor' in anaesthetized rats.

    Science.gov (United States)

    Hoult, J. R.; Moore, P. K.

    1981-01-01

    1. Prostaglandins E1, E2, I2 and endoperoxide analogue U46619 injected intra-arterially (i.a.) into anaesthetized rats at 2 micrograms/kg caused a substantial increase within 60 min of the plasma activity of prostaglandin 'reciprocal coupling factor' (RCF). RCF is the provisional name for the component(s) of plasma which inhibit microsomal prostaglandin synthesis and enhance cytosolic prostaglandin breakdown. 2. RCF is not released by inactive metabolite 13,14-dihydro-15-keto prostaglandin E2 (10 micrograms/kg, i.a.) or acetylcholine or histamine (2 micrograms/kg, i.a.). 3. We suggest that release by prostaglandins of RCF would provide the basis in vivo for a negative feedback mechanism controlling the activity of the prostaglandin system. PMID:7032632

  1. Reciprocal Regulation between Enterovirus 71 and the NLRP3 Inflammasome

    Directory of Open Access Journals (Sweden)

    Hongbin Wang

    2015-07-01

    Full Text Available Enterovirus 71 (EV71 is the major etiological agent of hand, foot, and mouth disease (HFMD. Early studies showed that EV71-infected patients with severe complications exhibited elevated plasma levels of IL-1β, indicating that EV71 may activate inflammasomes. Our current study demonstrates that the NLRP3 inflammasome plays a protective role against EV71 infection of mice in vivo. EV71 replication in myeloid cells results in the activation of the NLRP3 inflammasome and secretion of IL-1β. Conversely, EV71 counteracts inflammasome activation through cleavage of NLRP3 by viral proteases 2A and 3C, which cleave NLRP3 protein at the G493-L494 or Q225-G226 junction, respectively. Moreover, EV71 3C interacts with NLRP3 and inhibits IL-1β secretion when expressed in mammalian cells. These results thus reveal a set of reciprocal regulations between enterovirus 71 and the NLRP3 inflammasome.

  2. A single-reciprocating-piston two-phase thermofluidic prime-mover

    International Nuclear Information System (INIS)

    Taleb, Aly I.; Timmer, Michael A.G.; El-Shazly, Mohamed Y.; Samoilov, Aleksandr; Kirillov, Valeriy A.; Markides, Christos N.

    2016-01-01

    We explore theoretically a thermodynamic heat-engine concept that has the potential of attaining a high efficiency and power density relative to competing solutions, while having a simple construction with few moving parts and dynamic seals, allowing low capital and operating costs, and long lifetimes. Specifically, an unsteady heat-engine device within which a working fluid undergoes a power cycle featuring phase-change, termed the ‘Evaporative Reciprocating-Piston Engine’ (EPRE) is considered as a potential prime mover for use in combined heat and power (CHP) applications. Based on thermal/fluid-electrical analogies, a theoretical ERPE device is conceptualized initially in the electrical-analogy domain as a linearized, closed-loop active electronic circuit model. The circuit-model representation is designed to potentially exhibit high efficiencies compared to similar, existing two-phase unsteady heat engines. From the simplified circuit model in the electrical domain, and using the thermal/fluid-electrical analogies, one possible configuration of a corresponding physical ERPE device is derived, based on an early prototype of a device currently under development that exhibits some similarities with the ERPE, and used as a physical manifestation of the proposed concept. The corresponding physical ERPE device relies on the alternating phase change of a suitable working-fluid (here, water) to drive a reciprocating displacement of a single vertical piston and to produce sustained oscillations of thermodynamic properties within an enclosed space. Four performance indicators are considered: the operational frequency, the power output, the exergy efficiency, and the heat input/temperature difference imposed externally on the device's heat exchangers that is necessary to sustain oscillations. The effects of liquid inertia, viscous drag, hydrostatic pressure, vapour compressibility and two-phase heat transfer in the various engine components/compartments are

  3. Domains of reciprocity beyond monetary compensation: How do non-pecuniary factors affect effort and shirking?

    Directory of Open Access Journals (Sweden)

    Akinori Tomohara

    2016-12-01

    Full Text Available This empirical study examines how sources of reciprocity are related to work motivation by distinguishing positive and negative work attitudes in practical working environments. We move away from the unidimensional perspective of monetary compensation and investigate employees’ reciprocal behaviors, together with non-pecuniary aspects of work relations such as human relationships and company management. The results show that positive reciprocity, represented by effort, is fundamentally distinct from negative reciprocity, represented by shirking, when examining the multi-dimensional sources of reciprocity. Additionally, our analyses reveal that non-pecuniary factors in the working environment have a relatively large degree of association with work motivation, even when compared to monetary compensation. Our results complement those from controlled laboratory experiments.

  4. Perceptions of intimacy and friendship reciprocity moderate peer influence on aggression.

    Science.gov (United States)

    Meter, Diana J; Casper, Deborah M; Card, Noel A

    2015-01-01

    Previous research has shown that close friends' influence can exacerbate adolescents' aggressive behavior, but results of studies which examine whether friendships of greater or lesser qualities moderate peer influence effects are inconsistent. The present study tested whether the perception of the positive friendship quality of intimate exchange and friendship reciprocity moderated best friend influence on participant aggression over time. The 243 participants were approximately 12 years old and ethnically diverse. Neither intimate exchange nor reciprocity significantly moderated friend influence on aggression in a simple way, but the interaction of intimate exchange and friendship reciprocity predicted peer influence on participants' aggression over time. Specifically, highly intimate, nonreciprocal best friendships and less intimate, reciprocal best friendships showed greatest influence when friends' proportion of peer nominations for aggression was high. Reciprocity and intimacy should be considered when predicting peer influence on aggression. © 2014 Wiley Periodicals, Inc.

  5. Query-Adaptive Reciprocal Hash Tables for Nearest Neighbor Search.

    Science.gov (United States)

    Liu, Xianglong; Deng, Cheng; Lang, Bo; Tao, Dacheng; Li, Xuelong

    2016-02-01

    Recent years have witnessed the success of binary hashing techniques in approximate nearest neighbor search. In practice, multiple hash tables are usually built using hashing to cover more desired results in the hit buckets of each table. However, rare work studies the unified approach to constructing multiple informative hash tables using any type of hashing algorithms. Meanwhile, for multiple table search, it also lacks of a generic query-adaptive and fine-grained ranking scheme that can alleviate the binary quantization loss suffered in the standard hashing techniques. To solve the above problems, in this paper, we first regard the table construction as a selection problem over a set of candidate hash functions. With the graph representation of the function set, we propose an efficient solution that sequentially applies normalized dominant set to finding the most informative and independent hash functions for each table. To further reduce the redundancy between tables, we explore the reciprocal hash tables in a boosting manner, where the hash function graph is updated with high weights emphasized on the misclassified neighbor pairs of previous hash tables. To refine the ranking of the retrieved buckets within a certain Hamming radius from the query, we propose a query-adaptive bitwise weighting scheme to enable fine-grained bucket ranking in each hash table, exploiting the discriminative power of its hash functions and their complement for nearest neighbor search. Moreover, we integrate such scheme into the multiple table search using a fast, yet reciprocal table lookup algorithm within the adaptive weighted Hamming radius. In this paper, both the construction method and the query-adaptive search method are general and compatible with different types of hashing algorithms using different feature spaces and/or parameter settings. Our extensive experiments on several large-scale benchmarks demonstrate that the proposed techniques can significantly outperform both

  6. Testing for local adaptation in brown trout using reciprocal transplants

    Directory of Open Access Journals (Sweden)

    Stelkens Rike B

    2012-12-01

    Full Text Available Abstract Background Local adaptation can drive the divergence of populations but identification of the traits under selection remains a major challenge in evolutionary biology. Reciprocal transplant experiments are ideal tests of local adaptation, yet rarely used for higher vertebrates because of the mobility and potential invasiveness of non-native organisms. Here, we reciprocally transplanted 2500 brown trout (Salmo trutta embryos from five populations to investigate local adaptation in early life history traits. Embryos were bred in a full-factorial design and raised in natural riverbeds until emergence. Customized egg capsules were used to simulate the natural redd environment and allowed tracking the fate of every individual until retrieval. We predicted that 1 within sites, native populations would outperform non-natives, and 2 across sites, populations would show higher performance at ‘home’ compared to ‘away’ sites. Results There was no evidence for local adaptation but we found large differences in survival and hatching rates between sites, indicative of considerable variation in habitat quality. Survival was generally high across all populations (55% ± 3%, but ranged from 4% to 89% between sites. Average hatching rate was 25% ± 3% across populations ranging from 0% to 62% between sites. Conclusion This study provides rare empirical data on variation in early life history traits in a population network of a salmonid, and large-scale breeding and transplantation experiments like ours provide powerful tests for local adaptation. Despite the recently reported genetic and morphological differences between the populations in our study area, local adaptation at the embryo level is small, non-existent, or confined to ecological conditions that our experiment could not capture.

  7. A reciprocal connection factor for assessing knee-joint function.

    Science.gov (United States)

    Kim, Wangdo; Kohles, Sean S

    2012-01-01

    In the knee joint, interactions between instantaneous kinetics and kinematics associated with ligamentous and articular tissues are not fully understood. These structures may be represented by the instantaneous screw axis ($) (ISA) and static force vectors ($'). Geometric changes to the joint structure affecting motion have not been fully explained, especially after surgical reconstruction and replacement procedures. The ISA offers a joint-characterisation approach, which is dependent on the combined forces of ligaments, articular contacts and muscles. The standard four-bar linkage model in the sagittal plane demonstrates that the normal contact force and the lines of action of the cruciate ligaments always intersect at the centre of rotation of the joint. A kinematic knee model in which the articular surfaces in the lateral and medial compartments as well as the isometric fascicles in the engaged ligaments may be represented as five constraints in a one-degree-of-freedom parallel spatial mechanism. This study provides a theoretical foundation to elucidate the role of each of these elements in the control of the ISA. A recourse to the principle of virtual work explained through d'Alembert's principle for reducing a dynamics problem to an instantaneous static scenario allows screws to be applied to the biomechanics of human motion. The principle of reciprocity links these approaches together to explain the transmitting load between the tibia and the femur as well as the relative motion within the knee joint. A principal clinical implication of this study is the introduction of the reciprocal connection factor to evaluate knee kinematics and kinetics in one simple term, allowing the quantitative assessment of the outcome of knee-joint treatment and rehabilitation methods.

  8. The Identification of Microdeletion and Reciprocal Microduplication in 22q11.2 Using High-Resolution CMA Technology

    Directory of Open Access Journals (Sweden)

    Ana Julia Cunha Leite

    2016-01-01

    Full Text Available The chromosome 22q11.2 region has long been implicated in genomic diseases. Some genomic regions exhibit numerous low copy repeats with high identity in which they provide increased genomic instability and mediate deletions and duplications in many disorders. DiGeorge Syndrome is the most common deletion syndrome and reciprocal duplications could be occurring in half of the frequency of microdeletions. We described five patients with phenotypic variability that carries deletions or reciprocal duplications at 22q11.2 detected by Chromosomal Microarray Analysis. The CytoScan HD technology was used to detect changes in the genome copy number variation of patients who had clinical indication to global developmental delay and a normal karyotype. We observed in our study three microdeletions and two microduplications in 22q11.2 region with variable intervals containing known genes and unstudied transcripts as well as the LCRs that are often flanking and within this genomic rearrangement. The identification of these variants is of particular interest because it may provide insight into genes or genomic regions that are crucial for specific phenotypic manifestations and are useful to assist in the quest for understanding the mechanisms subjacent to genomic deletions and duplications.

  9. The Identification of Microdeletion and Reciprocal Microduplication in 22q11.2 Using High-Resolution CMA Technology.

    Science.gov (United States)

    Leite, Ana Julia Cunha; Pinto, Irene Plaza; Cunha, Damiana Mirian da Cruz E; Ribeiro, Cristiano Luiz; da Silva, Claudio Carlos; da Cruz, Aparecido Divino; Minasi, Lysa Bernardes

    2016-01-01

    The chromosome 22q11.2 region has long been implicated in genomic diseases. Some genomic regions exhibit numerous low copy repeats with high identity in which they provide increased genomic instability and mediate deletions and duplications in many disorders. DiGeorge Syndrome is the most common deletion syndrome and reciprocal duplications could be occurring in half of the frequency of microdeletions. We described five patients with phenotypic variability that carries deletions or reciprocal duplications at 22q11.2 detected by Chromosomal Microarray Analysis. The CytoScan HD technology was used to detect changes in the genome copy number variation of patients who had clinical indication to global developmental delay and a normal karyotype. We observed in our study three microdeletions and two microduplications in 22q11.2 region with variable intervals containing known genes and unstudied transcripts as well as the LCRs that are often flanking and within this genomic rearrangement. The identification of these variants is of particular interest because it may provide insight into genes or genomic regions that are crucial for specific phenotypic manifestations and are useful to assist in the quest for understanding the mechanisms subjacent to genomic deletions and duplications.

  10. Fatigue life enhancement of NiTi rotary endodontic instruments by progressive reciprocating operation.

    Science.gov (United States)

    Shin, C S; Huang, Y H; Chi, C W; Lin, C P

    2014-09-01

    To evaluate the effect of reciprocating amplitude and progressive angular increment on fatigue life enhancement of NiTi rotary endodontic instruments. ProTaper F2 instruments were operated in steel artificial canals with both stationary reciprocating (SR) and progressive reciprocating (PR) motions. The SR motions involved symmetric to and fro reciprocation of ± 180(o) , ± 135(o) , ± 90(o) , ± 60(o) and ± 45(o) . The PR motions were ± 45(o) stationary motion superimposed with angular increments of 7(o) , 11(o) , 22.5(o) or 31(o) whenever an instrument completed 1, 10 or 30 reciprocating cycles (rc). The fatigue lives were compared with those under continuous rotation (CR) and a reciprocating operation with a forward 144(o) and backward 72(o) motion proposed by Yared (2008). The statistical significance of these operating modes on fatigue life was examined using one way anova and post hoc Tukey's tests at P = 0.05. Fractographic analysis was also applied to probe the fracture mechanisms of different rotation motions. Fatigue life increased with decreasing reciprocating amplitude. Operating in the SR increased fatigue life by 355% over that in the CR. Except for the 22.5(o) increment, all PR motions yielded longer fatigue lives than the SR motion. A progressive reciprocating operation with a ± 45(o) reciprocating amplitude and a + 7(o) progressive angular increment every 10 reciprocating cycles (± 45(o) /10rc/+7(o) ) increased fatigue life by 990% over that in the CR motion. In terms of life enhancement over the CR motion, the larger the curvature the less are the differences between different movements. Single crack initiation sites were found in the CR and SR motions, while three crack initiation sites were typical in the ± 45(o) /10rc/+7(o) motion. Fatigue life increased with decreasing reciprocating amplitude in stationary reciprocation. A progressive reciprocating operation with ± 45(o) /10rc/+7(o) motion led to significant fatigue life enhancement and

  11. Reciprocity in Interaction: A Window on the First Year of Life in Autism

    Directory of Open Access Journals (Sweden)

    Fabio Apicella

    2013-01-01

    Full Text Available From early infancy onwards, young children appear motivated to engage reciprocally with others and share psychological states during dyadic interactions. Although poor reciprocity is one of the defining features of autism spectrum disorders (ASDs, few studies have focused on the direct assessment of real-life reciprocal behavior; consequently, our knowledge of the nature and the development of this core feature of autism is still limited. In this study, we describe the phenomenon of reciprocity in infant-caregiver interaction by analyzing family movies taken during the first year of life of 10 infants with ASD and 9 infants with typical development (TD. We analyzed reciprocal behaviors by means of a coding scheme developed for this purpose (caregiver-infant reciprocity scale (CIRS. Infants with ASD displayed less motor activity during the first semester and subsequently fewer vocalizations, compared to TD infants. Caregivers of ASD infants showed in the second semester shorter periods of involvement and a reduction of affectionate touch. These results suggest that from the first months of life a nonsynchronic motor-vocal pattern may interfere in different ways with the development of reciprocity in the primary relationship between infants later diagnosed with ASD and their caregivers.

  12. Tunable and non-reciprocal dual-wavelength SOA-fiber ring laser

    Science.gov (United States)

    Sabry, Yasser M.; Khalil, Kamal; Khalil, Diaa

    2017-02-01

    Dual-wavelength fiber lasers provide a low cost and simple method for the optical generation of microwave and THz radiation over the electrical techniques. The main reported technique for this purpose is based on the use of FBGs with two different and close wavelengths allowing these two wavelengths only to oscillate within a laser cavity comprising EDFA or SOA gain medium, where the latter provides much less homogeneous line-broadening and improved stability. Non-conventional FBGs and filtering mechanisms were reported all based on unidirectional configuration, where the two wavelengths propagate in the same direction in the ring laser. In this work, we report a tunable dual-wavelength ring laser including non-reciprocal circulators connected back to back providing uncommon path and allowing for having each wavelength rotating in a different direction in the ring. This technique provides the flexibility of controlling each of the wavelengths separately in terms of tunability, polarization and losses. Two tunable Fabry-Perot filters are inserted in the uncommon path and the wavelength of the CW and the CCW waves are controlled independently. Polarization controllers are used in the ring to achieve better stability and achieve single longitudinal mode of operation. For a given settings of the filters, the wavelength of the CW wave is 1485.2 nm while the CCW wave wavelength is 1488.5 nm. The generation of tunable dual wavelength laser is demonstrated by tuning of either of the Fabry-Perot filters. For instance, the CCW wave was tuned from 1532.2 nm to 1534.1 nm while holding the CW at 1535.2 nm. The results demonstrate the generation of tunable dual-wavelength laser output in the proposed nonreciprocal ring, which allows for tunable THz generation.

  13. Pions in the nuclear medium

    International Nuclear Information System (INIS)

    Chanfray, G.

    1996-07-01

    We discuss various aspects of pion physics in the nuclear medium. We first study s-wave pion-nucleus interaction in connection with chiral symmetry restoration and quark condensate in the nuclear medium. We then address the question of p-wave pion-nucleus interaction and collective pionic modes in nuclei and draw the consequences for in medium ππ correlations especially in the scalar-isoscalar channel. We finally discuss the modification of the rho meson mass spectrum at finite density and/or temperature in connection with relativistic heavy ion collisions

  14. Cyclic fatigue resistance of two reciprocating nickel-titanium instruments after immersion in sodium hypochlorite.

    Science.gov (United States)

    Pedullà, E; Grande, N M; Plotino, G; Palermo, F; Gambarini, G; Rapisarda, E

    2013-02-01

    To assess resistance to cyclic fatigue of reciprocating nickel-titanium ( NiTi ) files (Reciproc and WaveOne) after immersion in NaOCl solution over several time periods. A total of 90 new Reciproc R25 and WaveOne Primary were tested. The 45 files of the same brand were randomly assigned to three groups (n = 15) and submitted to the following immersion protocol in 5% NaOCl at 37 °C for 16 mm: no immersion (control), 1 or 5 min dynamically. The dynamic immersion and the following cyclic fatigue tests were performed using the appropriate preset reciprocation modes ('RECIPROC ALL' or 'WAVEONE ALL') in a specially designed endodontic motor. Resistance to cyclic fatigue was determined by recording time to fracture (TtF) in a stainless steel artificial canal with a 60° angle of curvature and 5 mm radius of curvature. The artificial canal was manufactured reproducing the instrument's size and taper. Data were analysed by 2-way analyses of variance. Resistance to cyclic fatigue of the same NiTi file was not significantly affected by immersion in NaOCl . Reciproc R25 was associated with a higher cyclic fatigue resistance in all groups compared to WaveOne Primary (P < 0.0001). Reciprocating dynamic immersion in NaOCl for 1 or 5 min did not reduce the cyclic fatigue resistance of NiTi files significantly. However, the type of reciprocating instrument influenced cyclic fatigue resistance with Reciproc R25 being more resistant than WaveOne Primary. © 2012 International Endodontic Journal.

  15. Extravasation of contrast medium during CT examination: An ...

    African Journals Online (AJOL)

    Introduction: extravasation is an adverse reaction to intravenous injection of contrast medium (CM) during CT examination. The objectives of this study are to determine the frequency, management and outcomes of extravasations and to assess risk factors for extravasation. Methods: every incident of extravasation which ...

  16. Measurement of Ground Electrical Conductivity for Planning Medium ...

    African Journals Online (AJOL)

    Results of propagation measurements are often required to improve the coverage of Medium Frequency (MF) broadcast transmitters. To achieve this, ground electrical conductivity measurement is one of the parameters often determined. In this study, ground conductivity has been measured around MF radio transmitters in ...

  17. Non-Reciprocal Geometric Wave Diode by Engineering Asymmetric Shapes of Nonlinear Materials

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Jie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Li, Nianbei [Tongji Univ., Shanghai Shi (China)

    2014-02-18

    Unidirectional nonreciprocal transport is at the heart of many fundamental problems and applications in both science and technology. Here we study how to design the novel wave diode devices to realize the non-reciprocal wave propagations. Analytical results reveal that such non-reciprocal wave propagation can be purely induced by asymmetric geometry in nonlinear materials. The detailed numerical simulations are performed for a more realistic geometric wave diode model with typical asymmetric shape, where good non-reciprocal wave diode effect has been demonstrated. The results open a way for making wave diodes efficiently simply through shape engineering.

  18. Measurements of reciprocity law failure in green-sensitive X-ray films.

    Science.gov (United States)

    Arnold, B A; Eisenberg, H; Bjärngard, B E

    1978-02-01

    Reciprocity law failure was measured for four brands of medical x-ray films exposed with intensifying screens. Three of the films are green light-sensitized for use in combination with green light-emitting rare-earth screens. These films showed larger reciprocity failure effects than one conventional blue-sensitive film, Dupont Cronex-2. Development conditions had a small effect on reciprocity failure. As part of the investigation, a detector was constructed with a response that accurately monitors the light emission from the double screen-cassette combination over a wide range of x-ray photon energies.

  19. Sparse Frequency Waveform Design for Radar-Embedded Communication

    Directory of Open Access Journals (Sweden)

    Chaoyun Mai

    2016-01-01

    Full Text Available According to the Tag application with function of covert communication, a method for sparse frequency waveform design based on radar-embedded communication is proposed. Firstly, sparse frequency waveforms are designed based on power spectral density fitting and quasi-Newton method. Secondly, the eigenvalue decomposition of the sparse frequency waveform sequence is used to get the dominant space. Finally the communication waveforms are designed through the projection of orthogonal pseudorandom vectors in the vertical subspace. Compared with the linear frequency modulation waveform, the sparse frequency waveform can further improve the bandwidth occupation of communication signals, thus achieving higher communication rate. A certain correlation exists between the reciprocally orthogonal communication signals samples and the sparse frequency waveform, which guarantees the low SER (signal error rate and LPI (low probability of intercept. The simulation results verify the effectiveness of this method.

  20. Differential Medium for Vibrio cholerae

    Science.gov (United States)

    Schrank, Gordon D.; Stager, Charles E.; Verwey, W. F.

    1973-01-01

    A differential medium designed for rapid presumptive identification of Vibrio cholerae was described and shown to be useful for enumeration of viable cholera vibrios in the presence of other intestinal bacteria. Images PMID:4764406

  1. The Role of Friendship Reciprocity in University Freshmen's Alcohol Consumption

    NARCIS (Netherlands)

    Giese, Helge; Stok, F Marijn; Renner, Britta

    BACKGROUND: The similarity of friends in the frequency and quantity of alcohol consumption is explored. METHOD: During their first semester, 57 psychology freshmen indicated weekly drinking frequency and quantity and nominated the three peers of this group they liked most. These nominations were

  2. Medium effects in direct reactions

    International Nuclear Information System (INIS)

    Karakoc, M; Bertulani, C

    2013-01-01

    We discuss medium corrections of the nucleon-nucleon (NN) cross sections and their influence on direct reactions at intermediate energies ≳50 MeV/nucleon. The results obtained with free NN cross sections are compared with those obtained with a geometrical treatment of Pauli-blocking and Dirac-Bruecker methods. We show that medium corrections may lead to sizable modifications for collisions at intermediate energies and that they are more pronounced in reactions involving weakly bound nuclei.

  3. Intermediaries in Trust: Indirect Reciprocity, Incentives, and Norms

    Directory of Open Access Journals (Sweden)

    Giangiacomo Bravo

    2015-01-01

    Full Text Available Any trust situation involves a certain amount of risk for trustors that trustees could abuse. In some cases, intermediaries exist who play a crucial role in the exchange by providing reputational information. To examine under what conditions intermediary opinion could have a positive impact on cooperation, we designed two experiments based on a modified version of the investment game where intermediaries rated the behaviour of trustees under various incentive schemes and different role structures. We found that intermediaries can increase trust if there is room for indirect reciprocity between the involved parties. We also found that the effect of monetary incentives and social norms cannot be clearly separable in these situations. If properly designed, monetary incentives for intermediaries can have a positive effect. On the one hand, when intermediary rewards are aligned with the trustor’s interest, investments and returns tend to increase. On the other hand, fixed monetary incentives perform less than any other incentive schemes and endogenous social norms in ensuring trust and fairness. These findings should make us reconsider the mantra of incentivization of social and public conventional policy.

  4. Predicting and detecting reciprocity between indirect ecological interactions and evolution.

    Science.gov (United States)

    Estes, James A; Brashares, Justin S; Power, Mary E

    2013-05-01

    Living nature can be thought of as a tapestry, defined not only by its constituent parts but also by how these parts are woven together. The weaving of this tapestry is a metaphor for species interactions, which can be divided into three broad classes: competitive, mutualistic, and consumptive. Direct interactions link together as more complex networks, for example, the joining of consumptive interactions into food webs. Food web dynamics are driven, in turn, by changes in the abundances of web members, whose numbers or biomass respond to bottom-up (resource limitation) and top-down (consumer limitation) forcing. The relative strengths of top-down and bottom-up forcing on the abundance of a given web member depend on its ecological context, including its topological position within the food web. Top-down effects by diverse consumers are nearly ubiquitous, in many cases influencing the structure and operation of ecosystems. While the ecological effects of such interactions are well known, far less is known of their evolutionary consequences. In this essay, we describe sundry consequences of these interaction chains on species and ecosystem processes, explain several known or suspected evolutionary effects of consumer-induced interaction chains, and identify areas where reciprocity between ecology and evolution involving the indirect effects of consumer-prey interaction chains might be further explored.

  5. Characterization of Consistent Completion of Reciprocal Comparison Matrices

    Directory of Open Access Journals (Sweden)

    Julio Benítez

    2014-01-01

    Full Text Available Analytic hierarchy process (AHP is a leading multi-attribute decision-aiding model that is designed to help make better choices when faced with complex decisions involving several dimensions. AHP, which enables qualitative analysis using a combination of subjective and objective information, is a multiple criteria decision analysis approach that uses hierarchical structured pairwise comparisons. One of the drawbacks of AHP is that a pairwise comparison cannot be completed by an actor or stakeholder not fully familiar with all the aspects of the problem. The authors have developed a completion based on a process of linearization that minimizes the matrix distance defined in terms of the Frobenius norm (a strictly convex minimization problem. In this paper, we characterize when an incomplete, positive, and reciprocal matrix can be completed to become a consistent matrix. We show that this characterization reduces the problem to the solution of a linear system of equations—a straightforward procedure. Various properties of such a completion are also developed using graph theory, including explicit calculation formulas. In real decision-making processes, facilitators conducting the study could use these characterizations to accept an incomplete comparison body given by an actor or to encourage the actor to further develop the comparison for the sake of consistency.

  6. Fitness consequences of reciprocally asymmetric hybridization between simultaneous hermaphrodites.

    Science.gov (United States)

    Wiwegweaw, Amporn; Seki, Keiichi; Utsuno, Hiroki; Asami, Takahiro

    2009-03-01

    Depending on fitness consequences, hybridization may rescue Inbred populations; generate premating barriers, reproductive Interference, or hybrid species; or extinguish a species. However, the fitness of hybrids is unpredictable without direct quantification of their performance in fitness components across multiple generations. The land snails Bradybaena pellucida and B. similaris, which are Indigenous and non-Indigenous in Japan, respectively, copulate with each other simultaneously and reciprocally. However, only B. pellucida produces hybrids, because it ends mating by removing the penis before transferring a spermatophore, while B. similaris Inseminates B. pellucida. To evaluate the strength of an Intrinsic postzygotic barrier against the hybrids produced by B. pellucida, we conducted breeding experiments in the laboratory and measured six life-history traits: (1) growth rate, (2) body weight at maturity, (3) number of days to first oviposition after being permitted to mate, (4) clutch size, (5) fecundity, and (6) hatchability. We also calculated the relative intrinsic fitness based on five of these trait values (excluding clutch size). F(1) hybrids exhibited heterosis in growth rate, body weight at maturity and relative intrinsic fitness. F(2) hybrids also showed heterosis in body weight at maturity. Nevertheless, the F(2) hybrids produced significantly fewer progeny than the mid-point value of the parental species. Thus, the F(2) hybrids exhibited weak out-breeding depression in reproduction, offsetting their vigor in body size. These results indicate that only a weak postzygotic barrier, contrasting with strong F(1) heterosis, has evolved during genetic divergence of the two sibling species in allopatry.

  7. Conformity enhances network reciprocity in evolutionary social dilemmas.

    Science.gov (United States)

    Szolnoki, Attila; Perc, Matjaž

    2015-02-06

    The pursuit of highest payoffs in evolutionary social dilemmas is risky and sometimes inferior to conformity. Choosing the most common strategy within the interaction range is safer because it ensures that the payoff of an individual will not be much lower than average. Herding instincts and crowd behaviour in humans and social animals also compel to conformity in their own right. Motivated by these facts, we here study the impact of conformity on the evolution of cooperation in social dilemmas. We show that an appropriate fraction of conformists within the population introduces an effective surface tension around cooperative clusters and ensures smooth interfaces between different strategy domains. Payoff-driven players brake the symmetry in favour of cooperation and enable an expansion of clusters past the boundaries imposed by traditional network reciprocity. This mechanism works even under the most testing conditions, and it is robust against variations of the interaction network as long as degree-normalized payoffs are applied. Conformity may thus be beneficial for the resolution of social dilemmas. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  8. Pullulan fermentation using a prototype rotational reciprocating plate impeller.

    Science.gov (United States)

    Lin, Yun; Thibault, Jules

    2013-05-01

    A rotational reciprocating plate impeller prototype, designed to improve the mixing homogeneity of viscous non-Newtonian fermentation broth, has been tested in pullulan fermentations. With this new impeller, the operating levels of several factors were investigated to improve pullulan production with Aureobasidium pullulans ATCC 42023 in a 22-L bioreactor using experimental designs. Because both high molecular weight (MW) and high concentration of pullulan were desired; the exopolysaccharide (EPS) concentration and the broth viscosity were used as optimization objective functions to be maximized. A 6-run uniform design was used to investigate five factors. Under the best operating conditions among the six runs, 29.0 g L(-1) EPS was produced at 102 h. This condition was used as the starting point for further investigation on the two statistically significant factors, the pH and the agitation speed. An 8-run 3-level custom design that investigates up to second-order effects was used in the second stage. An optimal zone of operating conditions for large quantity of high MW pullulan production was identified. A concentration of 23.3 g L(-1) EPS was produced at 78 h. This is equivalent to an EPS productivity of 0.30 g L(-1) h(-1). The corresponding apparent viscosity of the broth was 0.38 Pa s at the shear rate of 10 s(-1).

  9. Achievement Emotions and Academic Performance: Longitudinal Models of Reciprocal Effects.

    Science.gov (United States)

    Pekrun, Reinhard; Lichtenfeld, Stephanie; Marsh, Herbert W; Murayama, Kou; Goetz, Thomas

    2017-09-01

    A reciprocal effects model linking emotion and achievement over time is proposed. The model was tested using five annual waves of the Project for the Analysis of Learning and Achievement in Mathematics (PALMA) longitudinal study, which investigated adolescents' development in mathematics (Grades 5-9; N = 3,425 German students; mean starting age = 11.7 years; representative sample). Structural equation modeling showed that positive emotions (enjoyment, pride) positively predicted subsequent achievement (math end-of-the-year grades and test scores), and that achievement positively predicted these emotions, controlling for students' gender, intelligence, and family socioeconomic status. Negative emotions (anger, anxiety, shame, boredom, hopelessness) negatively predicted achievement, and achievement negatively predicted these emotions. The findings were robust across waves, achievement indicators, and school tracks, highlighting the importance of emotions for students' achievement and of achievement for the development of emotions. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

  10. Reciprocal carbonyl-carbonyl interactions in small molecules and proteins.

    Science.gov (United States)

    Rahim, Abdur; Saha, Pinaki; Jha, Kunal Kumar; Sukumar, Nagamani; Sarma, Bani Kanta

    2017-07-19

    Carbonyl-carbonyl n→π* interactions where a lone pair (n) of the oxygen atom of a carbonyl group is delocalized over the π* orbital of a nearby carbonyl group have attracted a lot of attention in recent years due to their ability to affect the 3D structure of small molecules, polyesters, peptides, and proteins. In this paper, we report the discovery of a "reciprocal" carbonyl-carbonyl interaction with substantial back and forth n→π* and π→π* electron delocalization between neighboring carbonyl groups. We have carried out experimental studies, analyses of crystallographic databases and theoretical calculations to show the presence of this interaction in both small molecules and proteins. In proteins, these interactions are primarily found in polyproline II (PPII) helices. As PPII are the most abundant secondary structures in unfolded proteins, we propose that these local interactions may have implications in protein folding.Carbonyl-carbonyl π* non covalent interactions affect the structure and stability of small molecules and proteins. Here, the authors carry out experimental studies, analyses of crystallographic databases and theoretical calculations to describe an additional type of carbonyl-carbonyl interaction.

  11. Noise-induced enhancement of network reciprocity in social dilemmas

    International Nuclear Information System (INIS)

    Zhang, Gui-Qing; Sun, Qi-Bo; Wang, Lin

    2013-01-01

    Highlights: • We introduce the noise-induced mechanism into the prisoner’s dilemma game. • Cooperation will be largely enhanced by introducing the noise into the calculation of fitness. • Despite the defectors prevail initially, the stressed factor still promotes the cooperation. • The mechanism studied here is helpful on different kinds of interaction networks. -- Abstract: The network reciprocity is an important dynamic rule fostering the emergence of cooperation among selfish individuals. This was reported firstly in the seminal work of Nowak and May, where individuals were arranged on the regular lattice network, and played the prisoner’s dilemma game (PDG). In the standard PDG, one often assumes that the players have perfect rationality. However, in reality, we human are far from rational agents, as we often make mistakes, and behave irrationally. Accordingly, in this work, we introduce the element of noise into the measurement of fitness, which is determined by the parameter α controlling the degree of noise. The considered noise-induced mechanism remarkably promotes the behavior of cooperation, which may be conducive to interpret the emergence of cooperation within the population

  12. Conversion frequence

    International Nuclear Information System (INIS)

    Sauteret, C.

    1987-03-01

    The experimental evidence of short wavelength for laser inertial confinement has strongly increased the interest in high efficiency harmonic conversion of powerful Nd: glass lasers. This work describes our high power harmonic conversion experiments performed using the same laser apparatus for doubling, tripling the three high power 1064 nm P102, OCTAL and PHEBUS lasers. In addition to the understanding the physics of harmonic conversion, this work includes the basic concepts allows us to improve the technique such as non colinear schemes, to extend this method to other frequencies (fourth generation) and to predict some physical limits [fr

  13. Effects of reciprocal teaching : A two-year intervention study among low achieving adolescents

    NARCIS (Netherlands)

    Okkinga, Mariska; van Gelderen, Amos; Sleegers, P.J.C.; van Steensel, Roel

    2015-01-01

    Low achieving adolescents are known to have difficulties with reading comprehension. This presentation discusses how reciprocal teaching can improve low achieving adolescents' reading comprehension in natural classroom settings (as opposed to small-group settings) and to what extent intervention

  14. Fast Silencing Reveals a Lost Role for Reciprocal Inhibition in Locomotion

    Science.gov (United States)

    Moult, Peter R.; Cottrell, Glen A.; Li, Wen-Chang

    2013-01-01

    Summary Alternating contractions of antagonistic muscle groups during locomotion are generated by spinal “half-center” networks coupled in antiphase by reciprocal inhibition. It is widely thought that reciprocal inhibition only coordinates the activity of these muscles. We have devised two methods to rapidly and selectively silence neurons on just one side of Xenopus tadpole spinal cord and hindbrain, which generate swimming rhythms. Silencing activity on one side led to rapid cessation of activity on the other side. Analyses reveal that this resulted from the depression of reciprocal inhibition connecting the two sides. Although critical neurons in intact tadpoles are capable of pacemaker firing individually, an effect that could support motor rhythms without inhibition, the swimming network itself requires ∼23 min to regain rhythmic activity after blocking inhibition pharmacologically, implying some homeostatic changes. We conclude therefore that reciprocal inhibition is critical for the generation of normal locomotor rhythm. PMID:23312521

  15. Root canal retreatment using reciprocating and continuous rotary nickel-titanium instruments

    Science.gov (United States)

    de Souza, Patricia Fonseca; Oliveira Goncalves, Leonardo Cantanhede; Franco Marques, Andre Augusto; Sponchiado Junior, Emilio Carlos; Roberti Garcia, Lucas da Fonseca; de Carvalho, Fredson Marcio Acris

    2015-01-01

    Objective: The complete filling material removal during endodontic retreatment is a clinical procedure difficult to achieve. The aim of this study was to evaluate the efficacy of reciprocating and continuous rotary nickel-titanium instruments used in root canal retreatment. Materials and Methods: Forty freshly extracted human premolars were cleaned and shaped by the crown-down technique, followed by filling by the lateral compaction technique. The teeth were randomly separated into two groups (n = 20), according to the system used for filling material removal: G1 - Reciproc and G2 - ProTaper Universal Retreatment System. The teeth were photographed under operating microscope at ×8 magnification; and the total area of the root canal and remaining filling material were quantified. Results: No statistically significant difference (P > 0.05) in residual filling material was observed between groups; however, the time required for filling removal was significantly shorter for Reciproc system (P retreatment was faster when reciprocating motion was used. PMID:26038656

  16. Coefficient Bounds for Some Families of Starlike and Convex Functions of Reciprocal Order

    Science.gov (United States)

    Arif, Muhammad; Darus, Maslina; Raza, Mohsan; Khan, Qaiser

    2014-01-01

    The aim of the present paper is to investigate coefficient estimates, Fekete-Szegő inequality, and upper bound of third Hankel determinant for some families of starlike and convex functions of reciprocal order. PMID:25506621

  17. PENINGKATAN KEMANDIRIAN MAHASISWA PENDIDIKAN FISIKA PADA MATA KULIAH MEKANIKA MELALUI METODE RECIPROCAL TEACHING

    Directory of Open Access Journals (Sweden)

    Fajar Fitri

    2016-03-01

    Full Text Available This research aims to describe thestudent independence after follow the Reciprocal Teaching of Learning. The subjects of this research are students in study program of physics education Ahmad Dahlan University who are studying Mechanics at school year of 2015/2016. Classroom Action Research consists of plan, do, and reflection. This activity repeated two cycles. The result is after follow the Reciprocal Teaching of Learning 80,3% students reached good individual and classical independence.This research aims to describe thestudent independence after follow the Reciprocal Teaching of Learning. The subjects of this research are students in study program of physics education Ahmad Dahlan University who are studying Mechanics at school year of 2015/2016. Classroom Action Research consists of plan, do, and reflection. This activity repeated two cycles. The result is after follow the Reciprocal Teaching of Learning 80,3% students reached good individual and classical independence.

  18. The evolution of non-reciprocal nuclear exchange in mushrooms as a consequence of genomic conflict

    NARCIS (Netherlands)

    Aanen, D.K.; Kuyper, T.W.; Debets, A.J.M.; Hoekstra, R.F.

    2004-01-01

    Heterothallic mushrooms accomplish sex by exchanging nuclei without cytoplasm. Hyphal fusions occur between haploid mycelia resulting from germinated spores and subsequent reciprocal nuclear exchange without cytoplasmic mixing. The resulting dikaryon is therefore a cytoplasmic mosaic with uniformly

  19. Love me, love my dog: an experimental study on social connections and indirect reciprocity

    OpenAIRE

    Liang, Pinghan; Meng, Juanjuan

    2013-01-01

    This paper conducts a laboratory experiment to investigate the role of social connections in behavioral indirect reciprocity. We provide the evidence of spillovers effects of social ties, e.g., the recipient’s indirect reciprocal act varies with the relations between the donor and a third party. Naturally occurring friendship is employed to study social connections. Thus, a beneficiary might either be a “friend” or a “stranger” of the donor. We demonstrate that knowing social connections sign...

  20. Identification of groundwater flow parameters using reciprocal data from hydraulic interference tests

    Science.gov (United States)

    Marinoni, Marianna; Delay, Frederick; Ackerer, Philippe; Riva, Monica; Guadagnini, Alberto

    2016-08-01

    We investigate the effect of considering reciprocal drawdown curves for the characterization of hydraulic properties of aquifer systems through inverse modeling based on interference well testing. Reciprocity implies that drawdown observed in a well B when pumping takes place from well A should strictly coincide with the drawdown observed in A when pumping in B with the same flow rate as in A. In this context, a critical point related to applications of hydraulic tomography is the assessment of the number of available independent drawdown data and their impact on the solution of the inverse problem. The issue arises when inverse modeling relies upon mathematical formulations of the classical single-continuum approach to flow in porous media grounded on Darcy's law. In these cases, introducing reciprocal drawdown curves in the database of an inverse problem is equivalent to duplicate some information, to a certain extent. We present a theoretical analysis of the way a Least-Square objective function and a Levenberg-Marquardt minimization algorithm are affected by the introduction of reciprocal information in the inverse problem. We also investigate the way these reciprocal data, eventually corrupted by measurement errors, influence model parameter identification in terms of: (a) the convergence of the inverse model, (b) the optimal values of parameter estimates, and (c) the associated estimation uncertainty. Our theoretical findings are exemplified through a suite of computational examples focused on block-heterogeneous systems with increased complexity level. We find that the introduction of noisy reciprocal information in the objective function of the inverse problem has a very limited influence on the optimal parameter estimates. Convergence of the inverse problem improves when adding diverse (nonreciprocal) drawdown series, but does not improve when reciprocal information is added to condition the flow model. The uncertainty on optimal parameter estimates is

  1. Reciprocal inhibition between motor neurons of the tibialis anterior and triceps surae in humans.

    Science.gov (United States)

    Yavuz, Utku Şükrü; Negro, Francesco; Diedrichs, Robin; Farina, Dario

    2018-01-31

    Motor neurons innervating antagonist muscles receive reciprocal inhibitory afferent inputs in order to facilitate the joint movement in the two directions. The present study investigates the mutual transmission of reciprocal inhibitory afferent inputs between the tibialis anterior (TA) and triceps surae (soleus and medial gastrocnemius) motor units. We assessed this mutual mechanism in large populations of motor units for building a statistical distribution of the inhibition amplitudes during standardized input to the motor neuron pools in order to minimize the effect of modulatory pathways. Single motor unit activities were identified using high-density surface electromyography (HDsEMG) recorded from the TA, soleus (Sol) and medial gastrocnemius (GM) muscles during isometric dorsi- and plantar-flexion. Reciprocal inhibition on the antagonist muscle was elicited by electrical stimulation of the tibial (TN) or common peroneal nerves (CPN). The probability density distributions of reflex strength for each muscle were estimated in order to examine the strength of mutual transmission of reciprocal inhibitory input. The results showed that the strength of reciprocal inhibition in the TA motor units was a 4-fold greater than for the GM and the Sol motor units. This suggests an asymmetric transmission of reciprocal inhibition between ankle extensor and flexor muscles. This asymmetry cannot be explained by differences in motor unit type composition between the investigated muscles since we sampled low-threshold motor units in all cases. Therefore, the differences observed for the strength of inhibition are presumably due to a differential reciprocal spindle afferent input and the relative contribution of non-reciprocal inhibitory pathways.

  2. In-situ investigations of structural changes during cyclic loading by high resolution reciprocal space mapping

    DEFF Research Database (Denmark)

    Diederichs, Annika M.; Thiel, Felix; Lienert, Ulrich

    2017-01-01

    Abstract A major failure reason for structural materials is fatigue-related damage due to repeatedly changing mechanical loads. During cyclic loading dislocations self-organize into characteristic ordered structures, which play a decisive role for the materials lifetime. These heterogeneous...... the materials behavior during cyclic deformation and to improve the material design. While monitoring macroscopic stress and strain during cyclic loading, reciprocal space maps of diffraction peaks from single grains are obtained with high resolution. High Resolution Reciprocal Space Mapping was applied...

  3. Relationship Reciprocation Modulates Resource Allocation in Adolescent Social Networks: Developmental Effects

    OpenAIRE

    Burnett Heyes, Stephanie; Jih, Yeou?Rong; Block, Per; Hiu, Chii?Fen; Holmes, Emily A.; Lau, Jennifer Y. F.

    2015-01-01

    Adolescence is characterized as a period of social reorientation toward peer relationships, entailing the emergence of sophisticated social abilities. Two studies (Study 1: N?=?42, ages 13?17; Study 2: N?=?81, ages 13?16) investigated age group differences in the impact of relationship reciprocation within school?based social networks on an experimental measure of cooperation behavior. Results suggest development between mid? and late adolescence in the extent to which reciprocation of social...

  4. Endodontic retreatment: clinical comparison of reciprocating systems versus rotary system in disinfecting root canals.

    Science.gov (United States)

    Martinho, Frederico C; Freitas, Lilian F; Nascimento, Gustavo G; Fernandes, Aleteia M; Leite, Fabio R M; Gomes, Ana P M; Camões, Izabel C G

    2015-07-01

    This clinical study was conducted to compare the effectiveness of single-file reciprocating systems and rotary systems in removing endotoxins and cultivable bacteria in endodontic retreatment. Thirty endodontically treated teeth with post-treatment apical periodontitis were selected. The specimens were divided into three groups according to the system used: WaveOne (n = 10), Reciproc instrument (n = 10), and ProTaper Universal Retreatment system (n = 10). Samples were collected before and after chemomechanical preparation. The irrigation was performed by using 2.5% sodium hypochlorite. A chromogenic limulus amebocyte lysate assay test was used to quantify endotoxins. Culture techniques were used to determine bacterial colony-forming unit counts. At baseline, endotoxins and cultivable bacteria were recovered from 100% of the root canal samples in a median value of 5.84 EU/mL and 4.98 × 10(3) CFU/mL, respectively. After CMP, no differences were found in the median percentage values of endotoxin reduction achieved with reciprocating systems-WaveOne [94.11%] and Reciproc [93.29%] and with rotary systems-ProTaper [94.98%] (P > 0.05). Both single-file reciprocating systems [WaveOne (98.27%) and Reciproc (99.54%)] and rotary system [ProTaper (98.73%)] were effective in reducing bacterial load (P > 0.05). Moreover, no differences were found among the systems tested. The Reciproc and WaveOne reciprocating systems were as effective as the ProTaper system for removal of endotoxins and bacteria in endodontic retreatment. All systems tested were effective to remove cultivable bacteria and endotoxin in endodontic retreatment. As no differences among systems were observed, it is possible to suggest that clinicians should choose the preferred technique to perform endodontic.

  5. Reciprocal- effects of parenting and borderline personality disorder symptoms in adolescent girls

    OpenAIRE

    Stepp, Stephanie D.; Whalen, Diana J.; Scott, Lori N.; Zalewski, Maureen; Loeber, Rolf; Hipwell, Alison E.

    2014-01-01

    Theories of borderline personality disorder (BPD) postulate that high-risk transactions between caregiver and child are important for the development and maintenance of the disorder. Little empirical evidence exists regarding the reciprocal effects of parenting on the development of BPD symptoms in adolescence. The impact of child and caregiver characteristics on this reciprocal relationship is also unknown. Thus, the current study examines bidirectional effects of parenting, specifically har...

  6. Application of the dual reciprocity boundary element method for numerical modelling of solidification process

    Directory of Open Access Journals (Sweden)

    E. Majchrzak

    2008-12-01

    Full Text Available The dual reciprocity boundary element method is applied for numerical modelling of solidification process. This variant of the BEM is connected with the transformation of the domain integral to the boundary integrals. In the paper the details of the dual reciprocity boundary element method are presented and the usefulness of this approach to solidification process modelling is demonstrated. In the final part of the paper the examples of computations are shown.

  7. The reciprocal constitutive features of a Middle Eastern partnership: The Russian–Syrian bilateral relations

    OpenAIRE

    Tudoroiu, Theodor

    2015-01-01

    Using the concept of reciprocal socialization, this article argues that the Damascus–Moscow partnership has been since 1970 a reciprocal constitutive relation that has influenced considerably the actions, interests, and identities of the two partners. During the last two decades of the Cold War it represented an almost ideal-type example of a relationship between a super-power and its regional ally that, through its complex consequences, shaped significantly the two partners themselves, the M...

  8. Influence of transcutaneous electrical nerve stimulation conditions on disynaptic reciprocal Ia inhibition and presynaptic inhibition in healthy adults.

    Science.gov (United States)

    Takeda, Kazuya; Tanabe, Shigeo; Koyama, Soichiro; Ushiroyama, Kosuke; Naoi, Yuki; Motoya, Ikuo; Sakurai, Hiroaki; Kanada, Yoshikiyo

    2017-03-01

    This study investigated the influence of stimulus conditions of transcutaneous electrical nerve stimulation (TENS) on disynaptic reciprocal Ia inhibition (RI) and presynaptic inhibition (D1 inhibition) in healthy adults. Eight healthy participants received TENS (stimulus frequencies of 50, 100, and 200 Hz) over the deep peroneal nerve and tibialis anterior (TA) muscle in the resting condition for 30 min. At pre- and post-intervention, the RI from the TA to the soleus (SOL) and D1 inhibition of the SOL alpha motor neuron were assessed by evoked electromyography. The results showed that RI was not changed by TENS at any stimulus frequency condition. Conversely, D1 inhibition was significantly changed by TENS regardless of the stimulus frequency. The present results and previous studies pertaining to RI suggest that the resting condition might strongly influence the lack of pre- vs. post-intervention change in the RI. Regarding the D1 inhibition, the present results suggest that the effect of TENS might be caused by post-tetanic potentiation. The knowledge gained from the present study might contribute to a better understanding of fundamental studies of TENS in healthy adults and its clinical application for stroke survivors.

  9. The Influence of Social Category and Reciprocity on Adults' and Children's Altruistic Behavior

    Directory of Open Access Journals (Sweden)

    Michaela Gummerum

    2009-04-01

    Full Text Available Evolutionary theories of altruism have suggested that reciprocal exchanges and ingroup favoritism have been important strategies leading to the evolution of altruistic behavior among strangers. This study investigates whether minimal information about an interaction partner's membership in a trivial social group affects the allocations of adults and children in dictator game, reciprocity in a sequential prisoner's dilemma, and altruistic punishment in a third-party punishment game. In all, 155 adults and 157 students from second and sixth grade played these three economic games in either an ingroup, outgroup, or neutral condition. Adults and sixth-grade children allocated more to ingroup than to outgroup receivers in the dictator game, and adults punished ingroup non-cooperators more in the third-party punishment game than outgroup non-cooperators. When additional information about the other player's past behavior was presented, adults reciprocated equally with ingroup, outgroup, and neutral players, whereas children from sixth grade reciprocated more with ingroup and neutral than with outgroup players. Overall, the results of this study support the importance of group membership and reciprocity for adults' and older elementary school children's altruistic behavior. For younger elementary school children, however, reciprocity and group membership do not serve as salient social information that influence their altruistic behavior.

  10. Evolution of cooperation: combining kin selection and reciprocal altruism into matrix games with social dilemmas.

    Science.gov (United States)

    Ale, Som B; Brown, Joel S; Sullivan, Amy T

    2013-01-01

    Darwinian selection should preclude cooperation from evolving; yet cooperation is widespread among organisms. We show how kin selection and reciprocal altruism can promote cooperation in diverse 2×2 matrix games (prisoner's dilemma, snowdrift, and hawk-dove). We visualize kin selection as non-random interactions with like-strategies interacting more than by chance. Reciprocal altruism emerges from iterated games where players have some likelihood of knowing the identity of other players. This perspective allows us to combine kin selection and reciprocal altruism into a general matrix game model. Both mechanisms operating together should influence the evolution of cooperation. In the absence of kin selection, reciprocal altruism may be an evolutionarily stable strategy but is unable to invade a population of non-co-operators. Similarly, it may take a high degree of relatedness to permit cooperation to supplant non-cooperation. Together, a little bit of reciprocal altruism can, however, greatly reduce the threshold at which kin selection promotes cooperation, and vice-versa. To properly frame applications and tests of cooperation, empiricists should consider kin selection and reciprocal altruism together rather than as alternatives, and they should be applied to a broader class of social dilemmas than just the prisoner's dilemma.

  11. Evolution of cooperation: combining kin selection and reciprocal altruism into matrix games with social dilemmas.

    Directory of Open Access Journals (Sweden)

    Som B Ale

    Full Text Available Darwinian selection should preclude cooperation from evolving; yet cooperation is widespread among organisms. We show how kin selection and reciprocal altruism can promote cooperation in diverse 2×2 matrix games (prisoner's dilemma, snowdrift, and hawk-dove. We visualize kin selection as non-random interactions with like-strategies interacting more than by chance. Reciprocal altruism emerges from iterated games where players have some likelihood of knowing the identity of other players. This perspective allows us to combine kin selection and reciprocal altruism into a general matrix game model. Both mechanisms operating together should influence the evolution of cooperation. In the absence of kin selection, reciprocal altruism may be an evolutionarily stable strategy but is unable to invade a population of non-co-operators. Similarly, it may take a high degree of relatedness to permit cooperation to supplant non-cooperation. Together, a little bit of reciprocal altruism can, however, greatly reduce the threshold at which kin selection promotes cooperation, and vice-versa. To properly frame applications and tests of cooperation, empiricists should consider kin selection and reciprocal altruism together rather than as alternatives, and they should be applied to a broader class of social dilemmas than just the prisoner's dilemma.

  12. Reciprocity: A Predictor of Mental Health and Continuity in Elderly People's Relationships? A Review

    Directory of Open Access Journals (Sweden)

    Live Fyrand

    2010-01-01

    Full Text Available Many studies have demonstrated that social relationships confer mental health benefits. This paper aims to identify whether and how reciprocity in social relationships predicts or is associated with mental health benefits as well as with continuity in elderly people's social relationships. The studies reviewed in this paper show that, among elders, being in a balanced or underbenefited reciprocal position predicts better mental health and life quality than being in an overbenefited position. Throughout the course of life, reciprocity evens out present and earlier reciprocal imbalances, securing continuity in close relationships—particularly between spouses and between elderly parents and adult children. In friendships, securing continuity seems to be based on the maintenance of independence based on balanced reciprocal relations, making these relationships more vulnerable. Due to the problems of conceptualization and measurement in the reviewed studies, one should be cautious in stating a final conclusion that the reciprocity norm has a universal positive effect on mental health and continuity in elderly people's relationships.

  13. Toward An Ethics of Reciprocity: Ethnobotanical Knowledge and Medicinal Plants as Cancer Therapies

    Directory of Open Access Journals (Sweden)

    John Charles Ryan

    2014-10-01

    Full Text Available This article develops a reciprocity ethics of the environment through a discussion of ethnobotanical medicines used in the treatment of cancer. The moral virtue of reciprocity, defined as the returning of good when good is received or anticipated, is central to the posthumanist rethinking of human relationships to the plant world. As herbal medicines are used progressively more around the globe and as plant diversity decreases as a result of habitat loss and climate change, an ethics of reciprocity should be a concern for environmental philosophers and conservationists. Aldo Leopold’s land ethic and J. Baird Callicott’s distinction between deontological and prudential environmental ethics provide theoretical contexts for the development of a reciprocity ethics vis-à-vis ethnobotanical species. While this article does not necessarily specify modes or forms of reciprocity, it does outline some of the more prominent ethnobotanical species used in the treatment of cancer, including those from Native American, African, Chinese, and Indian traditions. In the form of a dialogue between the fields of ethnobotany, herbal medicine, and environmental philosophy, this article presents a position from which further articulations of reciprocity can be developed, particularly those involving the rights of indigenous cultures and plants.

  14. Linear analysis of active-medium two-beam accelerator

    Directory of Open Access Journals (Sweden)

    Miron Voin

    2015-07-01

    Full Text Available We present detailed development of the linear theory of wakefield amplification by active medium and its possible application to a two-beam accelerator (TBA is discussed. A relativistic train of triggering microbunches traveling along a vacuum channel in an active medium confined by a cylindrical waveguide excites Cherenkov wake in the medium. The wake is a superposition of azimuthally symmetric transverse magnetic modes propagating along a confining waveguide, with a phase velocity equal to the velocity of the triggering bunches. The structure may be designed in such a way that the frequency of one of the modes is close to active-medium resonant frequency, resulting in amplification of the former and domination of a single mode far behind the trigger bunches. Another electron bunch placed in proper phase with the amplified wakefield may be accelerated by the latter. Importantly, the energy for acceleration is provided by the active medium and not the drive bunch as in a traditional TBA. Based on a simplified model, we analyze extensively the impact of various parameters on the wakefield amplification process.

  15. Operant conditioning of reciprocal inhibition in rat soleus muscle.

    Science.gov (United States)

    Chen, Xiang Yang; Chen, Lu; Chen, Yi; Wolpaw, Jonathan R

    2006-10-01

    Operant conditioning of the H-reflex, the electrical analog of the spinal stretch reflex (SSR), induces activity-dependent plasticity in the spinal cord and might be used to improve locomotion after spinal cord injury. To further assess the potential clinical significance of spinal reflex conditioning, this study asks whether another well-defined spinal reflex pathway, the disynaptic pathway underlying reciprocal inhibition (RI), can also be operantly conditioned. Sprague-Dawley rats were implanted with electromyographic (EMG) electrodes in right soleus (SOL) and tibialis anterior (TA) muscles and a stimulating cuff on the common peroneal (CP) nerve. When background EMG in both muscles remained in defined ranges, CP stimulation elicited the TA H-reflex and SOL RI. After collection of control data for 20 days, each rat was exposed for 50 days to up-conditioning (RIup mode) or down-conditioning (RIdown mode) in which food reward occurred if SOL RI evoked by CP stimulation was more (RIup mode) or less (RIdown mode) than a criterion. TA and SOL background EMG and TA M response remained stable. In every rat, RI conditioning was successful (i.e., change > or =20% in the correct direction). In the RIup rats, final SOL RI averaged 171+/- 28% (mean +/- SE) of control, and final TA H-reflex averaged 114 +/- 14%. In the RIdown rats, final SOL RI averaged 37 +/- 13% of control, and final TA H-reflex averaged 60 +/- 18%. Final SOL RI and TA H-reflex sizes were significantly correlated. Thus like the SSR and the H-reflex, RI can be operantly conditioned; and conditioning one reflex can affect another reflex as well.

  16. Improving gross anatomy learning using reciprocal peer teaching.

    Science.gov (United States)

    Manyama, Mange; Stafford, Renae; Mazyala, Erick; Lukanima, Anthony; Magele, Ndulu; Kidenya, Benson R; Kimwaga, Emmanuel; Msuya, Sifael; Kauki, Julius

    2016-03-22

    The use of cadavers in human anatomy teaching requires adequate number of anatomy instructors who can provide close supervision of the students. Most medical schools are facing challenges of lack of trained individuals to teach anatomy. Innovative techniques are therefore needed to impart adequate and relevant anatomical knowledge and skills. This study was conducted in order to evaluate the traditional teaching method and reciprocal peer teaching (RPT) method during anatomy dissection. Debriefing surveys were administered to the 227 first year medical students regarding merits, demerits and impact of both RPT and Traditional teaching experiences on student's preparedness prior to dissection, professionalism and communication skills. Out of this, 159 (70 %) completed the survey on traditional method while 148 (65.2 %) completed survey on RPT method. An observation tool for anatomy faculty was used to assess collaboration, professionalism and teaching skills among students. Student's scores on examinations done before introduction of RPT were compared with examinations scores after introduction of RPT. Our results show that the mean performance of students on objective examinations was significantly higher after introduction of RPT compared to the performance before introduction of RPT [63.7 ± 11.4 versus 58.6 ± 10, mean difference 5.1; 95 % CI = 4.0-6.3; p-value learning environment of the dissection groups was very active learning during RPT sessions and that professionalism was observed by most students during discussions. Introduction of RPT in our anatomy dissection laboratory was generally beneficial to both students and faculty. Both objective (student performance) and subjective data indicate that RPT improved student's performance and had a positive learning experience impact. Our future plan is to continue RPT practice and continually evaluate the RPT protocol.

  17. Reciprocal modulation of cognitive and emotional aspects in pianistic performances.

    Directory of Open Access Journals (Sweden)

    Marcia K Kodama Higuchi

    Full Text Available BACKGROUND: High level piano performance requires complex integration of perceptual, motor, cognitive and emotive skills. Observations in psychology and neuroscience studies have suggested reciprocal inhibitory modulation of the cognition by emotion and emotion by cognition. However, it is still unclear how cognitive states may influence the pianistic performance. The aim of the present study is to verify the influence of cognitive and affective attention in the piano performances. METHODS AND FINDINGS: Nine pianists were instructed to play the same piece of music, firstly focusing only on cognitive aspects of musical structure (cognitive performances, and secondly, paying attention solely on affective aspects (affective performances. Audio files from pianistic performances were examined using a computational model that retrieves nine specific musical features (descriptors--loudness, articulation, brightness, harmonic complexity, event detection, key clarity, mode detection, pulse clarity and repetition. In addition, the number of volunteers' errors in the recording sessions was counted. Comments from pianists about their thoughts during performances were also evaluated. The analyses of audio files throughout musical descriptors indicated that the affective performances have more: agogics, legatos, pianos phrasing, and less perception of event density when compared to the cognitive ones. Error analysis demonstrated that volunteers misplayed more left hand notes in the cognitive performances than in the affective ones. Volunteers also played more wrong notes in affective than in cognitive performances. These results correspond to the volunteers' comments that in the affective performances, the cognitive aspects of piano execution are inhibited, whereas in the cognitive performances, the expressiveness is inhibited. CONCLUSIONS: Therefore, the present results indicate that attention to the emotional aspects of performance enhances expressiveness

  18. Reciprocal modulation of cognitive and emotional aspects in pianistic performances.

    Science.gov (United States)

    Higuchi, Marcia K Kodama; Fornari, José; Del Ben, Cristina M; Graeff, Frederico G; Leite, João Pereira

    2011-01-01

    High level piano performance requires complex integration of perceptual, motor, cognitive and emotive skills. Observations in psychology and neuroscience studies have suggested reciprocal inhibitory modulation of the cognition by emotion and emotion by cognition. However, it is still unclear how cognitive states may influence the pianistic performance. The aim of the present study is to verify the influence of cognitive and affective attention in the piano performances. Nine pianists were instructed to play the same piece of music, firstly focusing only on cognitive aspects of musical structure (cognitive performances), and secondly, paying attention solely on affective aspects (affective performances). Audio files from pianistic performances were examined using a computational model that retrieves nine specific musical features (descriptors)--loudness, articulation, brightness, harmonic complexity, event detection, key clarity, mode detection, pulse clarity and repetition. In addition, the number of volunteers' errors in the recording sessions was counted. Comments from pianists about their thoughts during performances were also evaluated. The analyses of audio files throughout musical descriptors indicated that the affective performances have more: agogics, legatos, pianos phrasing, and less perception of event density when compared to the cognitive ones. Error analysis demonstrated that volunteers misplayed more left hand notes in the cognitive performances than in the affective ones. Volunteers also played more wrong notes in affective than in cognitive performances. These results correspond to the volunteers' comments that in the affective performances, the cognitive aspects of piano execution are inhibited, whereas in the cognitive performances, the expressiveness is inhibited. Therefore, the present results indicate that attention to the emotional aspects of performance enhances expressiveness, but constrains cognitive and motor skills in the piano execution

  19. Reciprocal crosses between Alabio and Mojosari ducks : early egg production

    Directory of Open Access Journals (Sweden)

    L.H Prasetyo

    2000-12-01

    Full Text Available alternative to increasing productivity and production efficiency. Crossbreeding has been used widely for increasing productivity, and in this experiment Alabio and Mojosari ducks were crossed reciprocally in order to evaluate their egg production and egg quality, when compared to their parental breeds. Four genotypes AA, AM, MA and MM were compared and each consisted of 50 layer ducks. Each animal was kept in individual cage, and individual egg production and egg quality were recorded. They were given layer feed containing 20% crude protein and 3000 kcal/kg metabolisable energy. Results showed that the crossbred ducks (AM and MA laid eggs earlier than their parental breeds (AA and MM, and MA laid earlier than AM. The weight of first eggs of the crossbreeds did not differ significantly, AM was the same as MM and MA the same as AA. For the body weight at first lay, MA and AM weighed in between their parental breeds, AA was the heaviest and then followed by MA, AM and MM. For the 3-month egg production, MA ducks laid significantly more egg than the other 3 genotypes, and this is related to the age of first lay being the earliest. In terms of egg quality such as egg weight, yolk color, weight and thickness of shell, weight of the white and HU value, the crossbred ducks showed quality in between AA and MM. The AM ducks tended to be closer to MM and MA closer to AA, and this shows a strong influence of maternal effects. The average level of heterosis for weight of first egg is 2.41% and for 3-month egg production is 2.1%, but for MA cross the heterosis level is 11.69% for egg production. The overall results showed that crossbreeds between Alabio and Mojosari have the potential in improving production traits in the effort to increase productivity and production efficiency.

  20. Reciprocal Modulation of Cognitive and Emotional Aspects in Pianistic Performances

    Science.gov (United States)

    Higuchi, Marcia K. Kodama; Fornari, José; Del Ben, Cristina M.; Graeff, Frederico G.; Leite, João Pereira

    2011-01-01

    Background High level piano performance requires complex integration of perceptual, motor, cognitive and emotive skills. Observations in psychology and neuroscience studies have suggested reciprocal inhibitory modulation of the cognition by emotion and emotion by cognition. However, it is still unclear how cognitive states may influence the pianistic performance. The aim of the present study is to verify the influence of cognitive and affective attention in the piano performances. Methods and Findings Nine pianists were instructed to play the same piece of music, firstly focusing only on cognitive aspects of musical structure (cognitive performances), and secondly, paying attention solely on affective aspects (affective performances). Audio files from pianistic performances were examined using a computational model that retrieves nine specific musical features (descriptors) – loudness, articulation, brightness, harmonic complexity, event detection, key clarity, mode detection, pulse clarity and repetition. In addition, the number of volunteers' errors in the recording sessions was counted. Comments from pianists about their thoughts during performances were also evaluated. The analyses of audio files throughout musical descriptors indicated that the affective performances have more: agogics, legatos, pianos phrasing, and less perception of event density when compared to the cognitive ones. Error analysis demonstrated that volunteers misplayed more left hand notes in the cognitive performances than in the affective ones. Volunteers also played more wrong notes in affective than in cognitive performances. These results correspond to the volunteers' comments that in the affective performances, the cognitive aspects of piano execution are inhibited, whereas in the cognitive performances, the expressiveness is inhibited. Conclusions Therefore, the present results indicate that attention to the emotional aspects of performance enhances expressiveness, but constrains

  1. Chemistry of the interstellar medium

    International Nuclear Information System (INIS)

    Umanskij, S.Ya.

    1979-01-01

    Some aspects of chemistry of interstellar gas-dust clouds are considered. The specific attention is paid to the molecule formation in the interstellar medium. Discussed are the process of hydrogen atom recombination on interstellar specks of dust as well as the formation of double-atom molecules. An ion-molecular mechanism plays the main role in the origination of multiatom molecules. It is noted, that the real progress in chemistry of the interstellar medium will be determined by the development of laboratory investigations at ultralow temperatures and study of the processes proceeding on solid surfaces

  2. Medium-term fluctuations and the "Great Ratios" of economic growth

    DEFF Research Database (Denmark)

    Groth, Christian; Madsen, Jakob B.

    2016-01-01

    Evidence for the OECD countries show that the “great ratios”, such as the unemployment rate, factor shares, Tobin’s q and the investment-capital ratio, fluctuate significantly on medium-term frequencies of 10-40 years duration. To explain these medium-term fluctuations, we establish a macro-dynam...

  3. Medium-term Fluctuations and the 'Great Ratios' of Economic Growth

    DEFF Research Database (Denmark)

    Groth, Christian; Madsen, Jakob Brøchner

    Evidence for the OECD countries show that the “great ratios”, such as the unemployment rate, factor shares, Tobin’s q and the investment-capital ratio, fluctuate significantly on medium-term frequencies of 10-40 years duration. To explain these medium-term fluctuations, we establish a macro-dynam...

  4. Finding flicker: critical differences in temporal frequency capture attention.

    Science.gov (United States)

    Cass, John; Van der Burg, Erik; Alais, David

    2011-01-01

    Rapid visual flicker is known to capture attention. Here we show slow flicker can also capture attention under reciprocal temporal conditions. Observers searched for a target line (vertical or horizontal) among tilted distractors. Distractor lines were surrounded by luminance modulating annuli, all flickering sinusoidally at 1.3 or 12.1 Hz, while the target's annulus flickered at frequencies within this range. Search times improved with increasing target/distractor frequency differences. For target-distractor frequency separations >5 Hz reaction times were minimal with high-frequency targets correctly identified more rapidly than low frequency targets (~400 ms). Critically, however, at these optimal frequency separations search times for low and high-frequency targets were unaffected by set size (slow flicker popped out from high flicker, and vice versa), indicating parallel and symmetric search performance when searching for high or low frequency targets. In a "cost" experiment using 1.3 and 12.1 Hz flicker, the unique flickering annulus sometimes surrounded a distractor and, on other trials, surrounded the target. When centered on a distractor, the unique frequency produced a clear and symmetrical search cost. Together, these symmetric pop-out and search costs demonstrate that temporal frequency is a pre-attentive visual feature capable of capturing attention, and that it is relative rather than absolute frequencies that are critical. The shape of the search functions strongly suggest that early visual temporal frequency filters underlie these effects.

  5. A new measure of child vocal reciprocity in children with autism spectrum disorder.

    Science.gov (United States)

    Harbison, Amy L; Woynaroski, Tiffany G; Tapp, Jon; Wade, Joshua W; Warlaumont, Anne S; Yoder, Paul J

    2018-03-06

    Children's vocal development occurs in the context of reciprocal exchanges with a communication partner who models "speechlike" productions. We propose a new measure of child vocal reciprocity, which we define as the degree to which an adult vocal response increases the probability of an immediately following child vocal response. Vocal reciprocity is likely to be associated with the speechlikeness of vocal communication in young children with autism spectrum disorder (ASD). Two studies were conducted to test the utility of the new measure. The first used simulated vocal samples with randomly sequenced child and adult vocalizations to test the accuracy of the proposed index of child vocal reciprocity. The second was an empirical study of 21 children with ASD who were preverbal or in the early stages of language development. Daylong vocal samples collected in the natural environment were computer analyzed to derive the proposed index of child vocal reciprocity, which was highly stable when derived from two daylong vocal samples and was associated with speechlikeness of vocal communication. This association was significant even when controlling for chance probability of child vocalizations to adult vocal responses, probability of adult vocalizations, or probability of child vocalizations. A valid measure of children's vocal reciprocity might eventually improve our ability to predict which children are on track to develop useful speech and/or are most likely to respond to language intervention. A link to a free, publicly-available software program to derive the new measure of child vocal reciprocity is provided. Autism Res 2018. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. Children and adults often engage in back-and-forth vocal exchanges. The extent to which they do so is believed to support children's early speech and language development. Two studies tested a new measure of child vocal reciprocity using computer-generated and real

  6. Micropropagation of dahlia in static liquid medium using slow-release tools of medium ingredients

    NARCIS (Netherlands)

    Klerk, de G.J.M.; Brugge, ter J.

    2011-01-01

    Growth of dahlia shoots in vitro was ca. 4 times faster in liquid medium than on solidified medium. In liquid standard medium (3% sucrose, macroelements according to Driver–Kuniyuki Walnut medium, microelements according to Murashige–Skoog medium, 0.44 µM benzylaminopurine), the major medium

  7. Frequencies of inaudible high-frequency sounds differentially affect brain activity: positive and negative hypersonic effects.

    Science.gov (United States)

    Fukushima, Ariko; Yagi, Reiko; Kawai, Norie; Honda, Manabu; Nishina, Emi; Oohashi, Tsutomu

    2014-01-01

    The hypersonic effect is a phenomenon in which sounds containing significant quantities of non-stationary high-frequency components (HFCs) above the human audible range (max. 20 kHz) activate the midbrain and diencephalon and evoke various physiological, psychological and behavioral responses. Yet important issues remain unverified, especially the relationship existing between the frequency of HFCs and the emergence of the hypersonic effect. In this study, to investigate the relationship between the hypersonic effect and HFC frequencies, we divided an HFC (above 16 kHz) of recorded gamelan music into 12 band components and applied them to subjects along with an audible component (below 16 kHz) to observe changes in the alpha2 frequency component (10-13 Hz) of spontaneous EEGs measured from centro-parieto-occipital regions (Alpha-2 EEG), which we previously reported as an index of the hypersonic effect. Our results showed reciprocal directional changes in Alpha-2 EEGs depending on the frequency of the HFCs presented with audible low-frequency component (LFC). When an HFC above approximately 32 kHz was applied, Alpha-2 EEG increased significantly compared to when only audible sound was applied (positive hypersonic effect), while, when an HFC below approximately 32 kHz was applied, the Alpha-2 EEG decreased (negative hypersonic effect). These findings suggest that the emergence of the hypersonic effect depends on the frequencies of inaudible HFC.

  8. Frequencies of inaudible high-frequency sounds differentially affect brain activity: positive and negative hypersonic effects.

    Directory of Open Access Journals (Sweden)

    Ariko Fukushima

    Full Text Available The hypersonic effect is a phenomenon in which sounds containing significant quantities of non-stationary high-frequency components (HFCs above the human audible range (max. 20 kHz activate the midbrain and diencephalon and evoke various physiological, psychological and behavioral responses. Yet important issues remain unverified, especially the relationship existing between the frequency of HFCs and the emergence of the hypersonic effect. In this study, to investigate the relationship between the hypersonic effect and HFC frequencies, we divided an HFC (above 16 kHz of recorded gamelan music into 12 band components and applied them to subjects along with an audible component (below 16 kHz to observe changes in the alpha2 frequency component (10-13 Hz of spontaneous EEGs measured from centro-parieto-occipital regions (Alpha-2 EEG, which we previously reported as an index of the hypersonic effect. Our results showed reciprocal directional changes in Alpha-2 EEGs depending on the frequency of the HFCs presented with audible low-frequency component (LFC. When an HFC above approximately 32 kHz was applied, Alpha-2 EEG increased significantly compared to when only audible sound was applied (positive hypersonic effect, while, when an HFC below approximately 32 kHz was applied, the Alpha-2 EEG decreased (negative hypersonic effect. These findings suggest that the emergence of the hypersonic effect depends on the frequencies of inaudible HFC.

  9. Animal Locomotion in Different Mediums

    Indian Academy of Sciences (India)

    Wetlands are repositories of unique biodiversity. Wetlandorganisms are well adapted to their habitat, lying at theinterface of aquatic and terrestrial environments. In order tounderstand their adaptations in a better way, it is essential tograsp the basic properties of the medium in which variousorganisms live. This is attempted ...

  10. Animal Locomotion in Different Mediums

    Indian Academy of Sciences (India)

    IAS Admin

    Fishes, moving in water encounter drag forces, which can be of considerable magnitude. If sudden movement is required to catch prey or escape predators in a viscous medium, it is only possible by the contraction of fast, white muscle fibres, which rely on anaerobic glycolysis pathways. Therefore, it is not surprising that.

  11. Molecular spectroscopy of interstellar medium

    International Nuclear Information System (INIS)

    Varshalovich, D.A.; Khersonskij, V.K.

    1980-01-01

    Experimental data obtained in the investigation into molecules of interstellar medium by molecular-spectroscopic methods are discussed generally. Ion-molecule reactions play a significant part in the formation of multiatom molecules in the interstellar medium as well as reactions proceeding on the surface of interstellar dust. More than 50 types of molecules have been detected in the interstellar medium at present. In a wide range of wave lengths over 500 spectral lines belonging to various molecules and molecular fragments have been recorded. Interstellar molecules permit to investigate interstellar gas from all the sides. They are a suitable indicator of the isotope composition of interstellar gas. Radio observations of interstellar molecules make it possible to effectively investigate kinematics and space structure both separate gas-dust complexes and total gas distribution in Galaxy. It is noted that achievements of molecular spectroscopy of the interstellar medium radically change representations of the chemical composition of interstellar gas, of isotope abundance and organic substance in the Universe

  12. Hadron photoproduction at medium energy

    International Nuclear Information System (INIS)

    Dainton, J.B.

    1985-04-01

    Results from measurements of multibody photoproduction at medium incident photon energy (2.8 to 4.8 GeV) are presented and discussed. Particular emphasis is placed on topics which are not well understood and which therefore motivate experiments with the upgraded electron accelerator and storage ring ELSA at the University of Bonn, FR Germany. (author)

  13. Further studies on the possible relationship between radiation-induced reciprocal translocations and intrinsic radiosensitivity of human tumor cells

    International Nuclear Information System (INIS)

    Virsik-Peuckert, P.; Rave-Fraenk, M.; Schmidberger, H.

    1996-01-01

    Background and purpose. The aim of the present study was to estimate yields of radiation-induced translocations in surviving cells of several human tumor cell lines and in normal diploid human fibroblasts, and to compare these yields with corresponding intrinsic radiosensitivities determined by standard colony-formation assay. Material and methods. The yields of radiation-induced reciprocal translocations were investigated by fluorescence in situ hybridization. Chromosomes no. 1 and no. 4 were 'painted' with fluorescent hybridization probes for whole chromosomes. Translocation yields and cell survival were determined for different doses up to 6 Gy of 200 kV X-rays. Results. We observed a higher frequency of reciprocal translocations in the radiosensitive cells MCF-7 and MDA-MB-436 than in the radioresistant cells CaSki, WiDr, A549 and normal skin fibroblasts. For primary squamous cell carcinoma cells, ZMK-1, an intermediate radiosensitivity and an intermediate translocation yield were observed. The dose-dependence of translocation yields involving chromosomes no. 1 or no. 4 varied in different cell lines: it was linear or linear with a plateau at higher doses. Conclusions. A comparison of the data obtained with chromosomes no. 1 and no. 4 in the investigated cell types, indicates that intrinsic radiosensitivity of different tumor cells observed at the survival level, is correlated with different translocation yields, respectively. This correlation was observed for all cell types investigated, independent of the number of copies of the painted chromosome per cell or the radiation dose. However, for low doses (under 1 Gy), the yields of translocations determined for the individual chromosomes seem to be too low for a discrimination between radioresistant or radiosensitive cells

  14. Expanding the clinical phenotype of the 3q29 microdeletion syndrome and characterization of the reciprocal microduplication

    Directory of Open Access Journals (Sweden)

    Friedrich Christopher A

    2008-04-01

    Full Text Available Abstract Background Interstitial deletions of 3q29 have been recently described as a microdeletion syndrome mediated by nonallelic homologous recombination between low-copy repeats resulting in an ~1.6 Mb common-sized deletion. Given the molecular mechanism causing the deletion, the reciprocal duplication is anticipated to occur with equal frequency, although only one family with this duplication has been reported. Results In this study we describe 14 individuals with microdeletions of 3q29, including one family with a mildly affected mother and two affected children, identified among 14,698 individuals with idiopathic mental retardation who were analyzed by array CGH. Eleven individuals had typical 1.6-Mb deletions. Three individuals had deletions that flank, span, or partially overlap the commonly deleted region. Although the clinical presentations of individuals with typical-sized deletions varied, several features were present in multiple individuals, including mental retardation and microcephaly. We also identified 19 individuals with duplications of 3q29, five of which appear to be the reciprocal duplication product of the 3q29 microdeletion and 14 of which flank, span, or partially overlap the common deletion region. The clinical features of individuals with microduplications of 3q29 also varied with few common features. De novo and inherited abnormalities were found in both the microdeletion and microduplication cohorts illustrating the need for parental samples to fully characterize these abnormalities. Conclusion Our report demonstrates that array CGH is especially suited to identify chromosome abnormalities with unclear or variable presentations.

  15. The importance of relational coordination and reciprocal learning for chronic illness care within primary care teams.

    Science.gov (United States)

    Noël, Polly Hitchcock; Lanham, Holly J; Palmer, Ray F; Leykum, Luci K; Parchman, Michael L

    2013-01-01

    Recent research from a complexity theory perspective suggests that implementation of complex models of care, such as the Chronic Care Model (CCM), requires strong relationships and learning capacities among primary care teams. Our primary aim was to assess the extent to which practice member perceptions of relational coordination and reciprocal learning were associated with the presence of CCM elements in community-based primary care practices. We used baseline measures from a cluster randomized controlled trial testing a practice facilitation intervention to implement the CCM and improve risk factor control for patients with Type 2 diabetes in small primary care practices. Practice members (i.e., physicians, nonphysician providers, and staff) completed baseline assessments, which included the Relational Coordination Scale, Reciprocal Learning Scale, and the Assessment of Chronic Illness Care (ACIC) survey, along with items assessing individual and clinic characteristics. To assess the association between Relational Coordination, Reciprocal Learning, and ACIC, we used a series of hierarchical linear regression models accounting for clustering of individual practice members within clinics and controlling for individual- and practice-level characteristics and tested for mediation effects. A total of 283 practice members from 39 clinics completed baseline measures. Relational Coordination scores were significantly and positively associated with ACIC scores (Model 1). When Reciprocal Learning was added, Relational Coordination remained a significant yet notably attenuated predictor of ACIC (Model 2). The mediation effect was significant (z = 9.3, p < .01); 24% of the association between Relational Coordination and ACIC scores was explained by Reciprocal Learning. Of the individual- and practice-level covariates included in Model 3, only the presence of an electronic medical record was significant; Relational Coordination and Reciprocal Learning remained significant

  16. Comparative evaluation of fracture and defect in reciproc and rotary files in severe curved root canals

    Directory of Open Access Journals (Sweden)

    Mahdis Bagherian

    2015-03-01

    Full Text Available Introduction: Root canal instrumentation is an important phase in root canal therapy. Since success in endodontic treatment depends on file defect and fracture, the aim of this study was to compare the evaluation of defect and fracture in rotary and reciproc files in severe curved root canals. Materials & Methods: In this experimental study, 60 mesial canals of human closed apex molars with more than 30° canal curvature were randomly divided into two groups. In first group M-two rotary files number# 15, 20, and 25 and in second group R25 reciproc file were used for filing, respectively. A ×8 magnifier was applied to evaluate the defect or fracture presence in each side and if it were observed, a new file would be replaced. Therefore, the number of prepared canals with each file and fractured or defective files and the place of fracture in root canal were recorded. Kaplan Meier curve and log rank test were done by using SPSS v.22. Results: In rotary group, seven and two files were fractured and defected, respectively and four files were fractured and no defect was observed in reciproc group. Although the mean of the number of prepared canals until fracture or defect in rotary and reciproc groups was 3.3 and 7.06, respectively, there were no significant differences between two systems. All file’s fractures occurred in apical regions . Conclusion: The results showed that there was no significant difference in defects or fractures of rotary and reciproc systems. Reciproc instruments can be more effective than rotary ones because the root canal preparation in rotary instruments is longer than in reciproc system.

  17. Parents and early immersion : reciprocity between home and immersion preschool

    OpenAIRE

    Hickey, Tina

    1999-01-01

    This study examines the importance of parental support for early immersion in the context of a study of Irish-medium pre-schools or naionrai. Data were collected from all of the major participants in this early immersion model, including parents, teachers, classroom assistants and inspectors, in addition to detailed tests of 225 three-year-old children. This allows an analysis, not only of the effect of the parents' support for the child's early learning in the naionra, but also of the impact...

  18. Reciprocal regulation of cephalosporin resistance in Enterococcus faecalis.

    Science.gov (United States)

    Kristich, Christopher J; Little, Jaime L; Hall, Cherisse L; Hoff, Jessica S

    2011-01-01

    Antibiotic-resistant enterococci are major causes of hospital-acquired infections and therefore represent a serious public health problem. One well-known risk factor for the acquisition of hospital-acquired enterococcal infections is prior therapy with broad-spectrum cephalosporin antibiotics. Enterococci can proliferate in patients undergoing cephalosporin therapy due to intrinsic cephalosporin resistance, a characteristic of the genus Enterococcus. However, the molecular basis for cephalosporin resistance in E. faecalis has yet to be adequately elucidated. Previously we determined that a putative Ser/Thr kinase, IreK (formerly PrkC), is required for intrinsic cephalosporin resistance in E. faecalis. Here we show that kinase activity is required for cephalosporin resistance and, further, that resistance in E. faecalis is reciprocally regulated by IreK and IreP, a PP2C-type protein phosphatase encoded immediately upstream of IreK. Mutants of two divergent lineages of E. faecalis lacking IreP exhibit remarkable hyperresistance to cephalosporins but not to antibiotics targeting other cellular processes. Further genetic analyses indicate that hyperresistance of the IreP mutant is mediated by the IreK kinase. Additionally, competition experiments reveal that hyperresistant ΔireP mutants exhibit a substantial fitness defect in the absence of antibiotics, providing an evolutionary rationale for the use of a complex signaling system to control intrinsic cephalosporin resistance. These results support a model in which IreK and IreP act antagonistically via protein phosphorylation and dephosphorylation as part of a signal transduction circuit to regulate cellular adaptation to cephalosporin-induced stress. As a major cause of hospital-acquired infections, antibiotic-resistant enterococci represent a serious public health problem. Enterococci are well-known to exhibit intrinsic resistance to broad-spectrum cephalosporin antibiotics, a trait that enables them to proliferate

  19. Configural face encoding and spatial frequency information.

    Science.gov (United States)

    Boutet, Isabelle; Collin, Charles; Faubert, Jocelyn

    2003-10-01

    Configural relations and a critical band of spatial frequencies (SFs) in the middle range are particularly important for face recognition. We report the results of four experiments in which the relationship between these two types of information was examined. In Experiments 1, 2A, and 2B, the face inversion effect (FIE) was used to probe configural face encoding. Recognition of upright and inverted faces and nonface objects was measured in four conditions: a no-filter condition and three SF conditions (low, medium, and high frequency). We found significant FIEs of comparable magnitudes for all frequency conditions. In Experiment 3, discrimination of faces on the basis of either configural or featural modifications was measured under the same four conditions. Although the ability to discriminate configural modifications was superior in the medium-frequency condition, so was the ability to discriminate featural modifications. We conclude that the band of SF that is critical for face recognition does not contribute preferentially to configural encoding.

  20. Elimination of Left-Right Reciprocal Coupling in the Adult Lamprey Spinal Cord Abolishes the Generation of Locomotor Activity

    Directory of Open Access Journals (Sweden)

    J. A. Messina

    2017-11-01

    Full Text Available The contribution of left-right reciprocal coupling between spinal locomotor networks to the generation of locomotor activity was tested in adult lampreys. Muscle recordings were made from normal animals as well as from experimental animals with rostral midline (ML spinal lesions (~13%→35% body length, BL, before and after spinal transections (T at 35% BL. Importantly, in the present study actual locomotor movements and muscle burst activity, as well as other motor activity, were initiated in whole animals by descending brain-spinal pathways in response to sensory stimulation of the anterior head. For experimental animals with ML spinal lesions, sensory stimulation could elicit well-coordinated locomotor muscle burst activity, but with some significant differences in the parameters of locomotor activity compared to those for normal animals. Computer models representing normal animals or experimental animals with ML spinal lesions could mimic many of the differences in locomotor activity. For experimental animals with ML and T spinal lesions, right and left rostral hemi-spinal cords, disconnected from intact caudal cord, usually produced tonic or unpatterned muscle activity. Hemi-spinal cords sometimes generated spontaneous or sensory-evoked relatively high frequency “burstlet” activity that probably is analogous to the previously described in vitro “fast rhythm”, which is thought to represent lamprey locomotor activity. However, “burstlet” activity in the present study had parameters and features that were very different than those for lamprey locomotor activity: average frequencies were ~25 Hz, but individual frequencies could be >50 Hz; burst proportions (BPs often varied with cycled time; “burstlet” activity usually was not accompanied by a rostrocaudal phase lag; and following ML spinal lesions alone, “burstlet” activity could occur in the presence or absence of swimming burst activity, suggesting the two were generated

  1. On wave propagation in a random micropolar generalized thermoelastic medium

    Directory of Open Access Journals (Sweden)

    Mitra Manindra

    2017-06-01

    Full Text Available This paper endeavours to study aspects of wave propagation in a random generalized-thermal micropolar elastic medium. The smooth perturbation technique conformable to stochastic differential equations has been employed. Six different types of waves propagate in the random medium. The dispersion equations have been derived. The effects due to random variations of micropolar elastic and generalized thermal parameters have been computed. Randomness causes change of phase speed and attenuation of waves. Attenuation coefficients for high frequency waves have been computed. Second moment properties have been briefly discussed with application to wave propagation in the random micropolar elastic medium. Integrals involving correlation functions have been transformed to radial forms. A special type of generalized thermo-mechanical auto-correlation functions has been used to approximately compute effects of random variations of parameters. Uncoupled problem has been briefly outlined.

  2. Reciprocal translocations in ageing mice and mice with long-term low-level 239Pu contamination

    International Nuclear Information System (INIS)

    Pacchierotti, F.; Andreozzi, U.; Russo, A.; Metalli, P.

    1983-01-01

    Single intravenous injections of 185 Bq monomeric 239 Pu were given to male mice, and the frequency of primary spermatocytes with reciprocal translocations, determined 724 days after treatment, was not significantly different from that of age-matched untreated controls. These old animals showed significantly higher aberration frequencies than young adults. The data therefore show that for low initial activity and very long retention time the possible cytogenetic effects of incorporated nuclide does not change the age-related pattern of increase of spontaneous chromosome aberrations. Considerations of the main variables involved in the induction of cytogenetic effects of incorporated plutonium, based on literature data, indicate that the initial injected activity, the estimated total accumulated average organ dose, and the retention time interact in a complex way; as far as can be seen at present, the effects seem to be dependent mainly on the initial activity at short times after contamination, while the retention time appears to be predominant in the case of long-term observations. (author)

  3. EDITORIAL: From reciprocal space to real space in surface science From reciprocal space to real space in surface science

    Science.gov (United States)

    Bartels, Ludwig; Ernst, Karl-Heinz

    2012-09-01

    cover image of this issue honors this achievement. It shows 27 chiral heptahelicene molecules arranged by one of the guest editors (KHE) with the very same STM at IBM Almaden Research Center, San José that was used for moving xenon atoms more than 20 years ago. Karl-Heinz Rieder's career, as briefly outlined in the biography by G Benedek in this issue, reflected this paradigm shift in surface science from reciprocal to real space investigations: initially focusing on helium scattering as a superior technique for the investigation of delicate surfaces, his group at the Freie University in Berlin became the second in the world to rearrange atoms and molecules at surfaces in a controlled way and they generated much of the foundational work of low temperature STM investigations. Besides his saxophone skills and many other hobbies, Karl-Heinz is a real poet and loves composing funny limericks and spoonerisms. He wrote the following poem (passed on to us by W-D Schneider) at the International School of Solid State Physics in 1998 in Erice, Italy. It is a real masterpiece, beautifully summarizing us all, the 'Surface Science Society'. The top atom sheetSome become real slaves is important and neat.looking at standing waves. Therefore there is a strong raceThe producers of coatings in the science of surface.get really good quotings. To clean it you needStill others use new ways ions and heat.with electrons and x-rays. Then the atoms arrangeAnd all has to be in some ways that are strange,in good UHV—except theory, they relax, reconstructwhich thinks on extensions as a matter of fact.to still lower dimensions, And reacting with gasesand with lots of computing they form quite new phasestries to get solid footing. with large unit cellsSo everybody with joy as diffraction tells.plays his own special toy. Some people use lightAnd all think they are better from a synchrotron brightshould get published a letter. and claim it is bestBut before there's more cluster to do this in

  4. Disentangling social selection and social influence effects on adolescent smoking: the importance of reciprocity in friendships.

    Science.gov (United States)

    Mercken, Liesbeth; Candel, Math; Willems, Paul; de Vries, Hein

    2007-09-01

    The goal of this study was to examine social selection and social influence within reciprocal and non-reciprocal friendships, and the role of parents and siblings, as factors explaining similarity of smoking behaviour among adolescent friends. A new social selection-social influence model is proposed. Longitudinal design with two measurements. Data were gathered among Dutch high school students in the control group of the European Smoking prevention Framework Approach (ESFA) study. The sample consisted of 1886 adolescents with a mean age of 12.7 years. The main outcome measures were the smoking behaviours of the respondents, best friends, parents and siblings. We tested the social selection-social influence model with structural equation modelling techniques. Social selection and social influence both played an important role in explaining similarity of smoking behaviour among friends. Within non-reciprocal friendships, only social selection explained similarity of smoking behaviour, whereas within reciprocal friendships, social influence and possibly also social selection explained similarity of smoking behaviour. Sibling smoking behaviour was a more important predictor of adolescent smoking behaviour than parental smoking behaviour. Social selection and social influence both promote similarity of smoking behaviour, and the impact of each process differs with the degree of reciprocity of friendships. These insights may contribute to further refinement of smoking prevention strategies.

  5. Comparison of retreatment ability of full-sequence reciprocating instrumentation and 360° rotary instrumentation.

    Science.gov (United States)

    Capar, Ismail Davut; Gok, Tuba; Orhan, Ezgi

    2015-12-01

    The purpose of the present study was to investigate the amount of root canal filling material after root canal filling removal with 360° rotary instrumentation or reciprocating motion with the same file sequence. Root canals of the 36 mandibular premolars were shaped with ProTaper Universal instruments up to size F2 and filled with corresponding single gutta-percha cone and sealer. The teeth were assigned to two retreatment groups (n = 18): group 1 360° rotational motion and group 2 reciprocating motion of ATR Tecnika motors (1310° clockwise and 578° counterclockwise). Retreatment procedure was performed with ProTaper Universal retreatment files with a sequence of D1-3 and ProTaper Universal F3 instruments. Total time required to remove filling material were recorded. Remaining filling material was examined under stereomicroscope at ×8 magnification. The data were analysed statistically using the Mann-Whitney U test, and testing was performed at 95 % confidence level (p  0.05) in terms of remaining filling material. The total time required for retreatment was shorter in 360° rotational motion group compared to reciprocating motion group (p < 0.05). Both continuous rotation and reciprocating motion showed similar effectiveness in terms of root canal filling material removal. Using ProTaper Universal retreatment instruments with reciprocating motion of ATR motor and conventional rotary motion have similar efficacy in root canal filling removal.

  6. Trajectories on the path to reciprocity-A theoretical framework for collaborating with socioeconomically disadvantaged communities.

    Science.gov (United States)

    Minas, Maria; Ribeiro, Maria Teresa; Anglin, James P

    2018-01-01

    The importance of cultivating connection to enhance individual, relational and collective well-being is gaining attention in the current literature on building community. Although these goals are being increasingly considered, the concept of reciprocity has been less prominent than may be warranted in the field of psychology. This article presents a theoretical framework on the dynamics of reciprocity which resulted from grounded theory (GT) research involving 2 complementary studies. The first study involved 22 participants from different socioeconomic backgrounds engaged in "reflecting-team with appreciative audiences" sessions (Madsen, 2007) in Portugal. The second study involved participant observation of 15 community programs recognized as good-practices in collaboration with socioeconomically disadvantaged participants, at national and international levels, across 9 countries. The theoretical framework emphasizes the centrality of building reciprocity for the development of individuals, families, communities, and programs. It integrates the trajectories of reciprocity; quadrants reflecting the standpoints assumed according to socioeconomic and cultural positions; basic social-psychological processes inherent to the process of building reciprocity; and characterizes different types of programs. The resulting framework is analyzed in relation to prior literature for a broader understanding of synergies and challenges, and the article concludes by suggesting implications for further research and practice. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  7. Intraoperative discomfort associated with the use of a rotary or reciprocating system: a prospective randomized clinical

    Directory of Open Access Journals (Sweden)

    Aline Cristine Gomes

    2017-05-01

    Full Text Available Objectives The aim of this randomized, controlled, prospective clinical study was to evaluate patients' intraoperative discomfort during root canal preparations in which either multi-file rotary (Mtwo or single-file reciprocating (Reciproc systems were used. Materials and Methods Fifty-five adult patients, aged between 25 and 69 years old, with irreversible pulpitis or pulp necrosis participated in this study. Either the mesiobuccal or the distobuccal canals for maxillary molars and either the mesiobuccal or the mesiolingual canals for mandibular molars were randomly chosen to be instrumented with Mtwo multi-file rotary or Reciproc single-file reciprocating systems. Immediately after each canal instrumentation under anesthesia, patient discomfort was assessed using a 1 - 10 visual analog scale (VAS, ranging from ‘least possible discomfort’ (1 to ‘greatest possible discomfort’ (10. The Wilcoxon signed-rank test was used to determine significant differences at p< 0.05. Results Little intraoperative discomfort was found in all cases. No statistically significant differences in intraoperative discomfort between the 2 systems were found (p = 0.660. Conclusions Root canal preparation with multi-file rotary or single-file reciprocating systems had similar and minimal effects on patients' intraoperative discomfort.

  8. Blue Thermomechanical Treatment Optimizes Fatigue Resistance and Flexibility of the Reciproc Files.

    Science.gov (United States)

    De-Deus, Gustavo; Silva, Emmanuel João Nogueira Leal; Vieira, Victor Talarico Leal; Belladonna, Felipe Gonçalves; Elias, Carlos Nelson; Plotino, Gianluca; Grande, Nicola Maria

    2017-03-01

    The aim of the present study was to evaluate the influence of Blue thermal treatment on the bending resistance and cyclic fatigue of conventional M-Wire Reciproc files (VDW, Munich, Germany). The roughness pattern and the microhardness of the files were also assessed. Flexibility of standard Reciproc R25 files and the corresponding Blue prototypes was determined by 45° bending tests according to the ISO 3630-1 specification. Instruments were also subjected to cyclic fatigue resistance, measuring the time to fracture in an artificial stainless steel canal with a 60° angle and a 5-mm radius of curvature. The fracture surface of all fragments was examined with a scanning electron microscope. The roughness of the working parts was quantified by using a profilometer, and the microhardness test was performed using the Vickers hardness tester. Results were statistically analyzed using the Student t test with a level of significance set at P  .05), whereas Reciproc Blue revealed significantly lower microhardness than the original Reciproc instrument (P < .05). Reciproc Blue nickel-titanium showed improved all-around performance when compared with conventional M-Wire superelastic nickel-titanium, demonstrating improved flexibility and fatigue resistance, and reduced microhardness while maintaining similar characteristics of the surface. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  9. RECIPROC VERSUS TWISTED FILE FOR ROOT CANAL FILLING REMOVAL:ASSESSMENT OF APICALLY EXTRUDED DEBRIS*

    Directory of Open Access Journals (Sweden)

    Demet ALTUNBAŞ

    2016-04-01

    Full Text Available Purpose: The aim of this study was to evaluate the amount of apically extruded debris during endodontic retreatment with different file systems. Materials and Methods: Sixty extracted human mandibular premolar teeth were used in this study. Root canals of the teeth were instrumented and filled before being randomly assigned to three groups. Guttapercha was removed using the Reciproc system, the Twisted File system (TF, and Hedström-files (H-file. Apically extruded debris was collected and dried in pre-weighed Eppendorf tubes. The amount of extruded debris was assessed with an electronic balance. Data were statistically analyzed using one-way ANOVA, Kruskal-Wallis, and Mann-Whitney U tests. Results: The Reciproc and TF systems extruded significantly less debris than the H-file (p<0.05. However, no significant difference was found between the Reciproc and TF systems. Conclusion: All tested file systems caused apical extrusion of debris. Both the rotary file (TF and the reciprocating single-file (Reciproc systems were associated with less apical extrusion compared with the H-file.

  10. Reciprocal selection causes a coevolutionary arms race between crossbills and lodgepole pine.

    Science.gov (United States)

    Benkman, Craig W; Parchman, Thomas L; Favis, Amanda; Siepielski, Adam M

    2003-08-01

    Few studies have shown both reciprocal selection and reciprocal adaptations for a coevolving system in the wild. The goal of our study was to determine whether the patterns of selection on Rocky Mountain lodgepole pine (Pinus contorta spp. latifolia) and red crossbills (Loxia curvirostra complex) were concordant with earlier published evidence of reciprocal adaptations in lodgepole pine and crossbills on isolated mountain ranges in the absence of red squirrels (Tamiasciurus hudsonicus). We found that selection (directional) by crossbills on lodgepole pine where Tamiasciurus are absent was divergent from the selection (directional) exerted by Tamiasciurus on lodgepole pine. This resulted in divergent selection between areas with and without Tamiasciurus that was congruent with the geographic patterns of cone variation. In the South Hills, Idaho, where Tamiasciurus are absent and red crossbills are thought to be coevolving with lodgepole pine, crossbills experienced stabilizing selection on bill size, with cone structure as the agent of selection. These results show that crossbills and lodgepole pine exhibit reciprocal adaptations in response to reciprocal selection, and they provide insight into the traits mediating and responding to selection in a coevolutionary arms race.

  11. Reciproc versus Twisted file for root canal filling removal: assessment of apically extruded debris.

    Science.gov (United States)

    Altunbas, Demet; Kutuk, Betul; Toyoglu, Mustafa; Kutlu, Gizem; Kustarci, Alper; Er, Kursat

    2016-01-01

    The aim of this study was to evaluate the amount of apically extruded debris during endodontic retreatment with different file systems. Sixty extracted human mandibular premolar teeth were used in this study. Root canals of the teeth were instrumented and filled before being randomly assigned to three groups. Guttapercha was removed using the Reciproc system, the Twisted File system (TF), and Hedström-files (H-file). Apically extruded debris was collected and dried in pre-weighed Eppendorf tubes. The amount of extruded debris was assessed with an electronic balance. Data were statistically analyzed using one-way ANOVA, Kruskal-Wallis, and Mann-Whitney U tests. The Reciproc and TF systems extruded significantly less debris than the H-file (p<0.05). However, no significant difference was found between the Reciproc and TF systems. All tested file systems caused apical extrusion of debris. Both the rotary file (TF) and the reciprocating single-file (Reciproc) systems were associated with less apical extrusion compared with the H-file.

  12. Soluble CD40 Ligand and Oxidative Response Are Reciprocally Stimulated during Shiga Toxin-Associated Hemolytic Uremic Syndrome

    Directory of Open Access Journals (Sweden)

    Maria J. Abrey Recalde

    2017-10-01

    Full Text Available Shiga toxin (Stx, produced by Escherichia coli, is the main pathogenic factor of diarrhea-associated hemolytic uremic syndrome (HUS, which is characterized by the obstruction of renal microvasculature by platelet-fibrin thrombi. It is well known that the oxidative imbalance generated by Stx induces platelet activation, contributing to thrombus formation. Moreover, activated platelets release soluble CD40 ligand (sCD40L, which in turn contributes to oxidative imbalance, triggering the release of reactive oxidative species (ROS on various cellular types. The aim of this work was to determine if the interaction between the oxidative response and platelet-derived sCD40L, as consequence of Stx-induced endothelium damage, participates in the pathogenic mechanism during HUS. Activated human glomerular endothelial cells (HGEC by Stx2 induced platelets to adhere to them. Although platelet adhesion did not contribute to endothelial damage, high levels of sCD40L were released to the medium. The release of sCD40L by activated platelets was inhibited by antioxidant treatment. Furthermore, we found increased levels of sCD40L in plasma from HUS patients, which were also able to trigger the respiratory burst in monocytes in a sCD40L-dependent manner. Thus, we concluded that platelet-derived sCD40L and the oxidative response are reciprocally stimulated during Stx2-associated HUS. This process may contribute to the evolution of glomerular occlusion and the microangiopathic lesions.

  13. X-ray computerized tomography based on the method of reciprocal projection with filtration by double differentiation. Procedure and information peculiarities

    International Nuclear Information System (INIS)

    Vajnberg, Eh.I.; Kazak, I.A.; Fajngojz, M.L.

    1985-01-01

    The results of experimental evaluation of procedure and information peculiarities of the method of reciprocal projection with filtration of projections by double differentiation (RPFDD) for the monitoring of industrial products are generalized. Succession of stages n the RPFDD method permits to separately optimize reconstruction of high-frequeny and low-frequency tomogram structure which sharply reduces the acuteness of contradictions of conventional scheme between the required increase of accuracy and intolerable growth of computerized charges. High accuracy of evaluation of the linear attenuation factor of low-frequency structures in a wide range of densities at the last stage of RPFDD scheme is attained despite the non-conventionally small range of values at earlier stages of computerized processing

  14. Medium modifications with recoil polarization

    Energy Technology Data Exchange (ETDEWEB)

    Brand, J.F.J. van den [Nationaal Instituut voor Kernfysica en Hoge Energiefysica, Amsterdam (Netherlands); Ent, R. [CEBAF, Newport News, VA (United States)

    1994-04-01

    The authors show that the virtual Compton scattering process allows for a precise study of the off-shell electron-nucleon vertex. In a separable model, they show the sensitivity to new unconstrained structure functions of the nucleon, beyond the usual Dirac and Pauli form factors. In addition, they show the sensitivity to bound nucleon form factors using the reaction 4He({rvec e},e{prime},{rvec p}){sup 3}H. A nucleon embedded in a nucleus represents a complex system. Firstly, the bound nucleon is necessarily off-shell and in principle a complete understanding of the dynamical structure of the nucleon is required in order to calculate its off-shell electromagnetic interaction. Secondly, one faces the possibility of genuine medium effects, such as for example quark-exchange contributions. Furthermore, the electromagnetic coupling to the bound nucleon is dependent on the nuclear dynamics through the self-energy of the nucleon in the nuclear medium.

  15. Medium modifications with recoil polarization

    International Nuclear Information System (INIS)

    Brand, J.F.J. van den; Ent, R.

    1994-01-01

    The authors show that the virtual Compton scattering process allows for a precise study of the off-shell electron-nucleon vertex. In a separable model, they show the sensitivity to new unconstrained structure functions of the nucleon, beyond the usual Dirac and Pauli form factors. In addition, they show the sensitivity to bound nucleon form factors using the reaction 4He(rvec e,e',rvec p) 3 H. A nucleon embedded in a nucleus represents a complex system. Firstly, the bound nucleon is necessarily off-shell and in principle a complete understanding of the dynamical structure of the nucleon is required in order to calculate its off-shell electromagnetic interaction. Secondly, one faces the possibility of genuine medium effects, such as for example quark-exchange contributions. Furthermore, the electromagnetic coupling to the bound nucleon is dependent on the nuclear dynamics through the self-energy of the nucleon in the nuclear medium

  16. The Spread of a Noise Field in a Dispersive Medium

    Directory of Open Access Journals (Sweden)

    Cohen Leon

    2010-01-01

    Full Text Available We discuss the production of induced noise by a pulse and the propagation of the noise in a dispersive medium. We present a simple model where the noise is the sum of pulses and where the mean of each pulse is random. We obtain explicit expressions for the standard deviation of the spatial noise as a function of time. We also formulate the problem in terms of a time-frequency phase space approach and in particular we use the Wigner distribution to define the spatial/spatial-frequency distribution.

  17. Probing the local interstellar medium

    International Nuclear Information System (INIS)

    Suess, S.T.; Dessler, A.J.

    1985-01-01

    The paper concerns the location of the heliospheric shock, in view of the discrepancy between the theoretical and experimental values. To determine whether the discrepancy may be attributed to parameters used to describe the local interstellar medium [LISM], the authors applied a sophisticated model of solar-wind expansion to deduce a range of parameters for the LISM. Both the interstellar magnetic field and the pressure due to galactic cosmic rays are considered. (U.K.)

  18. Explaining the gender difference in nightmare frequency.

    Science.gov (United States)

    Schredl, Michael

    2014-01-01

    A recent meta-analysis showed a robust gender difference in nightmare frequency of medium effect size in adolescents and young adults: Women tend to report nightmares more frequently than men. The present study, carried out in an unselected student sample, indicates that 2 factors mediate the gender difference in nightmare frequency: neuroticism and overall dream recall frequency. The effect of neuroticism on the gender difference and the finding that the gender difference in nightmare frequency emerges at an age of about 10 years suggest that gender-specific socialization processes may play an important role in explaining the gender differences in nightmare frequency in adolescents and young to middle-aged adults. This idea is supported by the previous finding that nightmare frequency is related to sex role orientation. However, longitudinal studies are necessary to validate these hypotheses.

  19. Medium Theory and Social Systems

    DEFF Research Database (Denmark)

    Tække, Jesper

    The  paper  first  gives  a  tentative  theoretical  explanation  of  the  concept  of media,  based  on  the  dichotomies  of  actual/potential  (meaning),  form/medium  (appearance),  and  substratum/material  content  (extension  in  time  and  space).  This  theoretical  explanation  presents......  seen as medium  for  formation. Finally  the  paper  takes  the micro  level  perspective  by  applying  the  theory  to  newsgroups,  interpreting  them as self-organizing interactive systems giving a differentiated and diversified scope for social  inclusion.  ......The  paper  first  gives  a  tentative  theoretical  explanation  of  the  concept  of media,  based  on  the  dichotomies  of  actual/potential  (meaning),  form/medium  (appearance),  and  substratum/material  content  (extension  in  time  and  space).  This  theoretical  explanation  presents......  the  possibility  for  observation both of a social micro and a social macro level from a medium perspective. In the next  section  the paper  frames  the macro  level by  a  tentative  synthesis of  the medium  theory  and  the  sociological systems theory briefly describing a socio...

  20. Non-Reciprocal Geometric Wave Diode by Engineering Asymmetric Shapes of Nonlinear Materials

    Science.gov (United States)

    Li, Nianbei; Ren, Jie

    2014-01-01

    Unidirectional nonreciprocal transport is at the heart of many fundamental problems and applications in both science and technology. Here we study the novel design of wave diode devices by engineering asymmetric shapes of nonlinear materials to realize the function of non-reciprocal wave propagations. We first show analytical results revealing that both nonlinearity and asymmetry are necessary to induce such non-reciprocal (asymmetric) wave propagations. Detailed numerical simulations are further performed for a more realistic geometric wave diode model with typical asymmetric shape, where good non-reciprocal wave diode effect is demonstrated. Finally, we discuss the scalability of geometric wave diodes. The results open a flexible way for designing wave diodes efficiently simply through shape engineering of nonlinear materials, which may find broad implications in controlling energy, mass and information transports. PMID:25169668

  1. Five-Year-Old Preschoolers’ Sharing is Influenced by Anticipated Reciprocation

    DEFF Research Database (Denmark)

    Xiong, Mingrui; Jiannong, Shi; Wu, Zhen

    2016-01-01

    more attractive than the child’s. In the reciprocal condition, the child was told that s/he would be a recipient when the partner played as a donor. In the non-reciprocal condition, however, the child was told that an anonymous child would be the recipient when the partner donated. Results showed...... that children shared more with the partner when they knew that they would be a recipient later. In Experiment 2, the child was always the recipient when the partner donated, but the partner’s resources were more desirable than the child’s in the high-value condition, and less desirable in the low......-value condition. We found that children were more generous when the partner’s resources were valued higher. These findings demonstrate that 5-year-old preschoolers’ sharing choices take into account the anticipated reciprocity of the recipient, suggesting either self-interested tactical sharing or direct...

  2. Emotion understanding, pictorial representations of friendship and reciprocity in school-aged children.

    Science.gov (United States)

    Laghi, Fiorenzo; Baiocco, Roberto; Di Norcia, Anna; Cannoni, Eleonora; Baumgartner, Emma; Bombi, Anna Silvia

    2014-01-01

    This study examined the relationship between emotional understanding, friendship representation and reciprocity in school-aged children. Two hundred and fifty-one Caucasian 6-year-old children (111 males and 140 females) took part in the study. The Test of Emotion Comprehension (TEC) and the Pictorial Assessment of Interpersonal Relationships (PAIR) were used. Children having a reciprocal friendship and children having a unilateral friendship with a child named as their "best friend" were compared on the emotional understanding task and on their pictorial representations of friendship. Multilevel analyses indicated that friendship status effects were not influenced by classroom-level differences. Results showed that children with reciprocal friendships drew themselves as more similar to and more cohesive with their best friends, and they showed better understanding of emotions, than children having a unilateral friendship. Finally, the implications of these findings for theoretical and empirical research development on friendship are discussed.

  3. Film, Parable, Reciprocity. Frederick Wiseman’s “Reality Fictions” and Social Change

    Directory of Open Access Journals (Sweden)

    Alyda Faber

    2016-11-01

    Full Text Available This essay argues that social criticism may be an effect of Frederick Wiseman’s “re¬ality fiction” films only if that effect is understood as analogous to that of parable, an awakened responsiveness to the unknown and the unresolved. The irresolution witnessed repeatedly in his films is the reality of “radical inequality” within institu¬tions in democracy, with domination ranging from explicit exploitative relations to subtle aural and bodily cues. Within those relations, Wiseman opens up the space of parable as a vision and practice of reciprocity and more-than-reciprocity through, among others, filmic strategies of “lyric portraiture” and expressive “democratic noise”. Furthermore, Wiseman’s camera extends more-than-reciprocity to animals in a filmic style that shows human and animal relations as visceral markers of what otherwise might remain unseen in human-to-human relations.

  4. Reciprocal synapses between mushroom body and dopamine neurons form a positive feedback loop required for learning.

    Science.gov (United States)

    Cervantes-Sandoval, Isaac; Phan, Anna; Chakraborty, Molee; Davis, Ronald L

    2017-05-10

    Current thought envisions dopamine neurons conveying the reinforcing effect of the unconditioned stimulus during associative learning to the axons of Drosophila mushroom body Kenyon cells for normal olfactory learning. Here, we show using functional GFP reconstitution experiments that Kenyon cells and dopamine neurons from axoaxonic reciprocal synapses. The dopamine neurons receive cholinergic input via nicotinic acetylcholine receptors from the Kenyon cells; knocking down these receptors impairs olfactory learning revealing the importance of these receptors at the synapse. Blocking the synaptic output of Kenyon cells during olfactory conditioning reduces presynaptic calcium transients in dopamine neurons, a finding consistent with reciprocal communication. Moreover, silencing Kenyon cells decreases the normal chronic activity of the dopamine neurons. Our results reveal a new and critical role for positive feedback onto dopamine neurons through reciprocal connections with Kenyon cells for normal olfactory learning.

  5. A game-theoretical approach for reciprocal security-related prevention investment decisions

    International Nuclear Information System (INIS)

    Reniers, Genserik; Soudan, Karel

    2010-01-01

    Every company situated within a chemical cluster faces important security risks from neighbouring companies. Investing in reciprocal security preventive measures is therefore necessary to avoid major accidents. These investments do not, however, provide a direct return on investment for the investor-company and thus plants are hesitative to invest. Moreover, there is likelihood that even if a company has fully invested in reciprocal security prevention, its neighbour has not, and as a result the company can experience a major accident caused by an initial (minor or major) accident that occurred in an adjacent chemical enterprise. In this article we employ a game-theoretic approach to interpret and model behaviour of two neighbouring chemical plants while negotiating and deciding on reciprocal security prevention investments.

  6. Why should the faculty adopt reciprocal teaching as part of the medical curriculum?

    Science.gov (United States)

    Khan, Muhammad Jaffar; Fatima, Sadia; Akhtar, Mehnaz; Owais, Muhammad

    2016-01-01

    Understanding the text is crucial to achieve depth in understanding of complex concepts for students at all levels of education for whom English is not their first language. Reciprocal teaching is an instructional activity that stimulate learning through a dialogue between teachers and students regarding segments of text. The process of summarizing, question-generating, clarifying and predicting allows the gaps to be recognised and filled by the student, who is in control of the learning process and able to analyse and reflect upon the reading material. Whereas reciprocal teaching has been applied at school and college level, little is known about its effectiveness in medical education. Incorporating reciprocal teaching in early years of medical education such as reading the literature and summarizing the flow of information in the study of integrated body systems could be an area to explore. Feasibility exercises and systematic validation studies are required to confirm authors' assertion.

  7. Using Video Modeling to Teach Reciprocal Pretend Play to Children with Autism

    Science.gov (United States)

    MacDonald, Rebecca; Sacramone, Shelly; Mansfield, Renee; Wiltz, Kristine; Ahearn, William H

    2009-01-01

    The purpose of the present study was to use video modeling to teach children with autism to engage in reciprocal pretend play with typically developing peers. Scripted play scenarios involving various verbalizations and play actions with adults as models were videotaped. Two children with autism were each paired with a typically developing child, and a multiple-probe design across three play sets was used to evaluate the effects of the video modeling procedure. Results indicated that both children with autism and the typically developing peers acquired the sequences of scripted verbalizations and play actions quickly and maintained this performance during follow-up probes. In addition, probes indicated an increase in the mean number of unscripted verbalizations as well as reciprocal verbal interactions and cooperative play. These findings are discussed as they relate to the development of reciprocal pretend-play repertoires in young children with autism. PMID:19721729

  8. Reciprocity-based experimental determination of dynamic forces and moments: A feasibility study

    Science.gov (United States)

    Ver, Istvan L.; Howe, Michael S.

    1994-01-01

    BBN Systems and Technologies has been tasked by the Georgia Tech Research Center to carry Task Assignment No. 7 for the NASA Langley Research Center to explore the feasibility of 'In-Situ Experimental Evaluation of the Source Strength of Complex Vibration Sources Utilizing Reciprocity.' The task was carried out under NASA Contract No. NAS1-19061. In flight it is not feasible to connect the vibration sources to their mounting points on the fuselage through force gauges to measure dynamic forces and moments directly. However, it is possible to measure the interior sound field or vibration response caused by these structureborne sound sources at many locations and invoke principle of reciprocity to predict the dynamic forces and moments. The work carried out in the framework of Task 7 was directed to explore the feasibility of reciprocity-based measurements of vibration forces and moments.

  9. [The bullied who bullies: the reciprocal relationship between victim and aggressor in workplace bullying situations].

    Science.gov (United States)

    Rodríguez Muñoz, Alfredo; Moreno Jiménez, Bernardo; Baillien, Elfi; Sanz Vergel, Ana Isabel; Moreno López, Ynomig

    2012-01-01

    The aim of this study was to explore longitudinal relationships between organizational factors (workload and procedural justice) and targets and perpetrators of workplace bullying. We compared several causal models (baseline or stability, normal, reversed and reciprocal models). The sample comprised 286 employees from two companies in Madrid, and we used a time-lag of one year. Results of structural equation modeling analyses showed that reciprocal model fit the data the best. We found that T1 workload was related positively to T2 target of bullying, and T1 procedural justice was related negatively to T2 target of bullying. There was a significant reverse effect of T1 target of bullying on T2 workload. Furthermore, we found a reciprocal relationship between being the target and the perpetrator of bullying. Overall, these findings emphasize the need to extend the traditional causal models of workplace bullying to more dynamic approaches.

  10. Opposing BOLD responses to reciprocated and unreciprocated altruism in putative reward pathways.

    Science.gov (United States)

    Rilling, James K; Sanfey, Alan G; Aronson, Jessica A; Nystrom, Leigh E; Cohen, Jonathan D

    2004-11-15

    Mesencephalic dopamine neurons are believed to facilitate reward-dependent learning by computing errors in reward predictions. We used fMRI to test whether this system was activated as expected in response to errors in predictions about whether a social partner would reciprocate an act of altruism. Nineteen subjects received fMRI scans as they played a series of single-shot Prisoner's Dilemma games with partners who were outside the scanner. In both ventromedial prefrontal cortex and ventral striatum, reciprocated and unreciprocated cooperation were associated with positive and negative BOLD responses, respectively. Our results are consistent with the hypothesis that mesencephalic dopamine projection sites carry information about errors in reward prediction that allow us to learn who can and cannot be trusted to reciprocate favors.

  11. Cyclic fatigue resistance of 3 different nickel-titanium reciprocating instruments in artificial canals.

    Science.gov (United States)

    Higuera, Oscar; Plotino, Gianluca; Tocci, Luigi; Carrillo, Gabriela; Gambarini, Gianluca; Jaramillo, David E

    2015-06-01

    The purpose of this study was to evaluate the cyclic fatigue resistance of 3 different nickel-titanium reciprocating instruments. A total of 45 nickel-titanium instruments were tested and divided into 3 experimental groups (n = 15): group 1, WaveOne Primary instruments; group 2, Reciproc R25 instruments; and group 3, Twisted File (TF) Adaptive M-L1 instruments. The instruments were then subjected to cyclic fatigue test on a static model consisting of a metal block with a simulated canal with 60° angle of curvature and a 5-mm radius of curvature. WaveOne Primary, Reciproc R25, and TF Adaptive instruments were activated by using their proprietary movements, WaveOne ALL, Reciproc ALL, and TF Adaptive, respectively. All instruments were activated until fracture occurred, and the time to fracture was recorded visually for each file with a 1/100-second chronometer. Mean number of cycles to failure and standard deviations were calculated for each group, and data were statistically analyzed (P < .05). Instruments were also observed through scanning electron microscopy to evaluate type of fracture. Cyclic fatigue resistance of Reciproc R25 and TF Adaptive M-L1 was significantly higher than that of WaveOne Primary (P = .009 and P = .002, respectively). The results showed no statistically significant difference between TF Adaptive M-L1 and Reciproc R25 (P = .686). Analysis of the fractured portion under scanning electron microscopy indicated that all instruments showed morphologic characteristics of ductile fracture that were due to accumulation of metal fatigue. No statistically significant differences were found between the instruments tested except for WaveOne Primary, which showed the lowest resistance to cyclic fatigue. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  12. Market powers predict reciprocal grooming in golden snub-nosed monkeys (Rhinopithecus roxellana.

    Directory of Open Access Journals (Sweden)

    Wei Wei

    Full Text Available Social grooming is a common form of affiliative behavior in primates. Biological market theory suggests that grooming can be traded either for grooming or other social commodities and services. When no other services are exchanged, grooming is predicted to be approximately reciprocated within a dyad. In contrast, the amount of reciprocal grooming should decrease as other offered services increase. We studied grooming patterns between polygamous male and female in golden snub-nosed monkeys (Rhinopithecus roxellana from the Qinling Mountains of central China and found that about 29.7% of grooming bouts were reciprocated. However, the durations of grooming bouts offered and returned was asymmetrical within dyads. In bisexual dyads, more grooming was initiated by females than males, which became more pronounced as the number of females per one-male unit increased. The rate of copulation per day for each female was positively correlated with the total duration of grooming time females invested in males.. Females without an infant (non-mothers directed more grooming towards females with an infant (mothers and were significantly more likely to be non-reciprocated. There was a significant negative relationship between non-mother and mother grooming duration and the rate of infants per female in each one-male unit. High-ranking females also received more grooming from low-ranking females than vice versa. The rate of food-related aggressive interactions was per day for low-ranking females was negatively correlated with the duration of grooming that low-ranking females gave to high-ranking females. Our results showed that grooming reciprocation in R. roxellana was discrepancy. This investment-reciprocity rate could be explained by the exchange of other social services in lieu of grooming.

  13. PENERAPAN PEMBELAJARAN RECIPROCAL TEACHING BERBANTUAN PETA KONSEP UNTUK MENINGKATKAN KEMAMPUAN BERPIKIR KRITIS SISWA PADA PEMBELAJARAN BIOLOGI

    Directory of Open Access Journals (Sweden)

    Hera Adiwijaya

    2016-01-01

    Full Text Available This research  aims to determine the influence of reciprocal teaching learning aided concept maps to students critical thinking skills in learning biology. The design of the study is a quasi-experimental design with research subjects in class X student of Agricultural Product Processing Technology (TPHP and  class X student of Fishery Products Processing Technology (TPHPi. Differences of the students critical thinking skills in the both class analyzed by using Anacova test. The results showed that there is an positive effect of reciprocal teaching learning aided concept maps to the critical thinking ability of students. The critical thinking of students’ in the experimental class (average percentage of critical thinking skills of students 73,36% was higher than the control group (average percentage of students' critical thinking skills 53,20%. From the results of the study it can be concluded that the application of reciprocal teaching learning  aided concept maps can enhance students’ critical thinking skills in learning biology. Penelitian ini bertujuan mengetahui pengaruh pembelajaran reciprocal teaching berbantuan peta konsep terhadap kemampuan berpikir kritis siswa pada pembelajaran biologi. Rancangan penelitian yang digunakan adalah rancangan eksperimen semu dengan subjek penelitian siswa pada kelas X  Teknologi Pengolahan Hasil Pertanian (TPHP dan siswa kelas X Teknologi Pengolahan Hasil Perikanan (TPHPi. Perbedaan kemampuan berpikir kritis siswa pada kedua kelas dianalisis  menggunakan uji Anacova. Hasil penelitian menunjukkan bahwa ada pengaruh positif pembelajaran reciprocal teaching berbantuan peta konsep terhadap kemampuan berpikir kritis siswa. Kemampuan berpikir kritis siswa pada kelas eksperimen (rata-rata persentase kemampuan berpikir kritis siswa 73,36% lebih tinggi dibandingkan kelas kontrol (rata-rata persentase kemampuan berpikir kritis siswa 53,20%. Dari hasil penelitian disimpulkan bahwa penerapan pembelajaran

  14. Market powers predict reciprocal grooming in golden snub-nosed monkeys (Rhinopithecus roxellana).

    Science.gov (United States)

    Wei, Wei; Qi, Xiao-Guang; Guo, Song-Tao; Zhao, Da-Peng; Zhang, Peng; Huang, Kang; Li, Bao-Guo

    2012-01-01

    Social grooming is a common form of affiliative behavior in primates. Biological market theory suggests that grooming can be traded either for grooming or other social commodities and services. When no other services are exchanged, grooming is predicted to be approximately reciprocated within a dyad. In contrast, the amount of reciprocal grooming should decrease as other offered services increase. We studied grooming patterns between polygamous male and female in golden snub-nosed monkeys (Rhinopithecus roxellana) from the Qinling Mountains of central China and found that about 29.7% of grooming bouts were reciprocated. However, the durations of grooming bouts offered and returned was asymmetrical within dyads. In bisexual dyads, more grooming was initiated by females than males, which became more pronounced as the number of females per one-male unit increased. The rate of copulation per day for each female was positively correlated with the total duration of grooming time females invested in males.. Females without an infant (non-mothers) directed more grooming towards females with an infant (mothers) and were significantly more likely to be non-reciprocated. There was a significant negative relationship between non-mother and mother grooming duration and the rate of infants per female in each one-male unit. High-ranking females also received more grooming from low-ranking females than vice versa. The rate of food-related aggressive interactions was per day for low-ranking females was negatively correlated with the duration of grooming that low-ranking females gave to high-ranking females. Our results showed that grooming reciprocation in R. roxellana was discrepancy. This investment-reciprocity rate could be explained by the exchange of other social services in lieu of grooming.

  15. Influence of continuous or reciprocating motion on cyclic fatigue resistance of 4 different nickel-titanium rotary instruments.

    Science.gov (United States)

    Pedullà, Eugenio; Grande, Nicola M; Plotino, Gianluca; Gambarini, Gianluca; Rapisarda, Ernesto

    2013-02-01

    The aim of this study was to evaluate the resistance to flexural fatigue of Reciproc R25 (VDW, Munich, Germany), WaveOne Primary (VDW, Munich, Germany), Mtwo (Sweden & Martina, Padova, Italy), and Twisted File (TF; SybronEndo, Orange, CA) instruments used in continuous rotation or in 2 different reciprocating motions. A total of 180 nickel-titanium files from 4 brands marketed, 2 for use in reciprocating motion (ie, Reciproc R25 and WaveOne Primary) and 2 for use in continuous rotation (ie, Mtwo and TF both taper .06/0.25 tip diameter), were tested. Forty-five instruments for each brand were divided into 3 groups (n = 15) on the basis of the motion tested: continuous rotation (group 1: 300 rpm) and reciprocal motion (group 2: "RECIPROC ALL" mode and group 3: "WAVEONE ALL" mode). The resistance to cyclic fatigue was determined by counting the number of cycles to failure in a 60° curve with a 5-mm radius. Data were analyzed through 2-way analyses of variance. The cyclic fatigue resistance of the 2 reciprocating motion instruments (ie, "RECIPROC ALL" and "WAVEONE ALL") was significantly higher than the continuous rotation in each brand (P .05). When considering the appropriate clinical motion for each brand, no significant difference in cyclic fatigue was found between TF, Mtwo, and Reciproc R25 instruments, whereas the cyclic fatigue resistance of WaveOne files was less than the other 3 brands (P < .05). Reciprocal motion showed a significantly higher cyclic fatigue resistance in all brands compared with continuous rotation. No differences were found between the 2 reciprocating motions. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  16. Flute and Shank Dimensions of Reciprocating Instruments before and after Simulated Root Canal shaping.

    Science.gov (United States)

    Sampaio, Felipe C; Brito, Ana Pp; Veloso, Heloisa Hp; de Alencar, Ana Hg; Decurcio, Daniel de A; de Figueiredo, José Ap; Estrela, Carlos

    2017-03-01

    This study analyzed the effect of the dimensions of the flute and shank in the first 4 mm of instrument tips on the deformation and dimensional changes of reciprocating instruments after root canal shaping (RCS). The reciprocating instruments used were Reciproc ® R25, R40, and R50; WaveOne ® Small, Primary, and Large; and Unicone ® #20, #25, and #40. Scanning electron microscopy images of the first 4 mm of the tip were acquired at 30× magnification before and after simulated curved root canals were shaped. Each instrument was used only once. The images were transferred to the AxioVision ® software to measure the flute area (μm 2 ), shank area (μm 2 ), flute length (μm), and cross-sectional diameter (μm). Student's t test for paired samples was used to compare differences before and after RCS, and analysis of variance followed by the Tukey test, to compare differences between instruments of similar sizes. The instruments were classified according to deformations after RCS. Reciproc ® instruments had larger flutes and smaller shanks. The Reciproc ® R40 had significant differences in cross-sectional diameter at 0.5 mm from the tip. Reciproc ® had no plastic deformations. Unicone ® #20 instruments had significant differences in cross-sectional diameter at 1.5 and 3.0 mm from the tip, and #25 instruments had differences at 1.5 and 3.0 mm and in length of the second and third flutes. One #20 and three #40 instruments had plastic deformations. The differences in length of the first and fourth flutes of WaveOne ® Primary and in cross-sectional diameter at 2.0 mm from the tip of WaveOne ® Large were significant. Two of three WaveOne ® Large instruments had plastic deformations. Reciproc ® instruments had greater flute areas and lengths and smaller shanks than Unicone ® and WaveOne ® instruments of similar sizes. Reciproc ® instruments had a greater flute-to-shank ratio. WaveOne ® instruments had the lowest flute-to-shank ratio. Unicone ® instruments

  17. The universal power and efficiency characteristics for irreversible reciprocating heat engine cycles

    CERN Document Server

    Qin Xiao Yong; Sun Feng Rui; Wu Chih

    2003-01-01

    The performance of irreversible reciprocating heat engine cycles with heat transfer loss and friction-like term loss is analysed using finite-time thermodynamics. The universal relations between the power output and the compression ratio, between the thermal efficiency and the compression ratio, and the optimal relation between power output and the efficiency of the cycles are derived. Moreover, analysis and optimization of the model were carried out in order to investigate the effect of cycle processes on the performance of the cycle using numerical examples. The results obtained herein include the performance characteristics of irreversible reciprocating Diesel, Otto, Atkinson and Brayton cycles.

  18. An examination of a reciprocal relationship between network governance and network structure

    DEFF Research Database (Denmark)

    Bergenholtz, Carsten; Goduscheit, René Chester

    2011-01-01

    with the overall structural relations between the actors in the network. These streams of research do contain references to each other but they mainly rely on a static conception of the relationship between network structure and the applied network governance. Based on a case study of a loosely coupled Danish...... inter-organisational innovation network, the proposition is that a reciprocal relationship between network governance and network structure can be identified. Such a reciprocal relationship involves theoretical and practical implications for how to govern an inter-organisational network....

  19. A directionally-selective neuromorphic circuit based on reciprocal synapses in Starburst Amacrine Cells.

    Science.gov (United States)

    Tseng, Ko-Chung; Parker, Alice C; Joshi, Jonathan

    2011-01-01

    Starburst Amacrine Cells (SACs) play a major role in the detection of directional motion in the biological retina. The starburst amacrine cell has intrinsic electrical mechanisms for producing directional selectivity (DS). GABA transmitter-receptor interactions between two overlapping SACs make DS more robust. We present a compartmentalized CMOS neuromorphic circuit that models a portion of two biological starburst amacrine cells in the retina and includes a simplified model of reciprocal interaction between the dendritic branches of SACs. We demonstrate that a neuromorphic circuit incorporating the reciprocal synapses enhances the responses in the neuromorphic dendritic tip and generates robust directional selectivity.

  20. Integration of neutron time-of-flight single-crystal Bragg peaks in reciprocal space

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Arthur J [ORNL; Joergensen, Mads [ORNL; Wang, Xiaoping [ORNL; Mikkelson, Ruth L [ORNL; Mikkelson, Dennis J [ORNL; Lynch, Vickie E [ORNL; Peterson, Peter F [ORNL; Green, Mark L [ORNL; Hoffmann, Christina [ORNL

    2014-01-01

    The intensity of single crystal Bragg peaks obtained by mapping neutron time-of-flight event data into reciprocal space and integrating in various ways are compared. These include spherical integration with a fixed radius, ellipsoid fitting and integrating of the peak intensity and one-dimensional peak profile fitting. In comparison to intensities obtained by integrating in real detector histogram space, the data integrated in reciprocal space results in better agreement factors and more accurate atomic parameters. Furthermore, structure refinement using integrated intensities from one-dimensional profile fitting is demonstrated to be more accurate than simple peak-minus-background integration.