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Sample records for cooper pair transfer

  1. Detecting nonlocal Cooper pair entanglement by optical Bell inequality violation

    Energy Technology Data Exchange (ETDEWEB)

    Nigg, Simon E.; Tiwari, Rakesh P.; Walter, Stefan; Schmidt, Thomas L. [Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel (Switzerland)

    2015-07-01

    Based on the Bardeen Cooper Schrieffer (BCS) theory of superconductivity, the coherent splitting of Cooper pairs from a superconductor to two spatially separated quantum dots has been predicted to generate nonlocal pairs of entangled electrons. In order to test this hypothesis, we propose a scheme to transfer the spin state of a split Cooper pair onto the polarization state of a pair of optical photons. We show that the produced photon pairs can be used to violate a Bell inequality, unambiguously demonstrating the entanglement of the split Cooper pairs.

  2. Detecting nonlocal Cooper pair entanglement by optical Bell inequality violation

    Science.gov (United States)

    Nigg, Simon E.; Tiwari, Rakesh P.; Walter, Stefan; Schmidt, Thomas L.

    2015-03-01

    Based on the Bardeen-Cooper-Schrieffer theory of superconductivity, the coherent splitting of Cooper pairs from a superconductor to two spatially separated quantum dots has been predicted to generate nonlocal pairs of entangled electrons. In order to test this hypothesis, we propose a scheme to transfer the spin state of a split Cooper pair onto the polarization state of a pair of optical photons. We show that the photon pairs produced can be used to violate a Bell inequality, unambiguously demonstrating the entanglement of the split Cooper pairs.

  3. Detecting nonlocal Cooper pair entanglement by optical Bell inequality violation

    OpenAIRE

    Nigg, Simon E.; Tiwari, Rakesh P.; Walter, Stefan; Schmidt, Thomas L.

    2014-01-01

    Based on the Bardeen Cooper Schrieffer (BCS) theory of superconductivity, the coherent splitting of Cooper pairs from a superconductor to two spatially separated quantum dots has been predicted to generate nonlocal pairs of entangled electrons. In order to test this hypothesis, we propose a scheme to transfer the spin state of a split Cooper pair onto the polarization state of a pair of optical photons. We show that the produced photon pairs can be used to violate a Bell inequality, unambiguo...

  4. Excited cooper pairs

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Arrietea, M. G.; Solis, M. A.; De Llano, M. [Universidad Nacional Autonoma de Mexico, Mexico, D.F (Mexico)

    2001-02-01

    Excited cooper pairs formed in a many-fermion system are those with nonzero total center-of mass momentum (CMM). They are normally neglected in the standard Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity for being too few compared with zero CMM pairs. However, a Bose-Einstein condensation picture requires both zero and nonzero CMM pairs. Assuming a BCS model interaction between fermions we determine the populations for all CMM values of Cooper pairs by actually calculating the number of nonzero-CMM pairs relative to that of zero-CMM ones in both 2D and 3D. Although this ratio decreases rapidly with CMM, the number of Cooper pairs for any specific CMM less than the maximum (or breakup of the pair) momentum turns out to be typically larger than about 95% of those with zero-CMM at zero temperature T. Even at T {approx}100 K this fraction en 2D is still as large as about 70% for typical quasi-2D cuprate superconductor parameters. [Spanish] Los pares de cooper excitados formados en un sistema de muchos electrones, son aquellos con momentos de centro de masa (CMM) diferente de cero. Normalmente estos no son tomados en cuenta en la teoria estandar de la superconductividad de Bardeen-Cooper-Schrieffer (BCS) al suponer que su numero es muy pequeno comparados con los pares de centro de masa igual a cero. Sin embargo, un esquema de condensacion Bose-Einstein requiere de ambos pares, con CMM cero y diferente de cero. Asumiendo una interaccion modelo BCS entre los fermiones, determinamos la poblacion de pares cooper con cada uno de todos los posibles valores del CMM calculando el numero de pares con momentos de centro de masa diferente de cero relativo a los pares de CMM igual a cero, en 2D y 3D. Aunque esta razon decrece rapidamente con el CMM, el numero de pares de cooper para cualquier CMM especifico menor que el momento maximo (o rompimiento de par) es tipicamente mas grande que el 95% de aquellos con CMM cero. Aun a T {approx}100 K esta fraccion en 2D es

  5. Cooper Pairs in Insulators?

    International Nuclear Information System (INIS)

    Valles, James

    2008-01-01

    Nearly 50 years elapsed between the discovery of superconductivity and the emergence of the microscopic theory describing this zero resistance state. The explanation required a novel phase of matter in which conduction electrons joined in weakly bound pairs and condensed with other pairs into a single quantum state. Surprisingly, this Cooper pair formation has also been invoked to account for recently uncovered high-resistance or insulating phases of matter. To address this possibility, we have used nanotechnology to create an insulating system that we can probe directly for Cooper pairs. I will present the evidence that Cooper pairs exist and dominate the electrical transport in these insulators and I will discuss how these findings provide new insight into superconductor to insulator quantum phase transitions.

  6. Junctionless Cooper pair transistor

    Energy Technology Data Exchange (ETDEWEB)

    Arutyunov, K. Yu., E-mail: konstantin.yu.arutyunov@jyu.fi [National Research University Higher School of Economics , Moscow Institute of Electronics and Mathematics, 101000 Moscow (Russian Federation); P.L. Kapitza Institute for Physical Problems RAS , Moscow 119334 (Russian Federation); Lehtinen, J.S. [VTT Technical Research Centre of Finland Ltd., Centre for Metrology MIKES, P.O. Box 1000, FI-02044 VTT (Finland)

    2017-02-15

    Highlights: • Junctionless Cooper pair box. • Quantum phase slips. • Coulomb blockade and gate modulation of the Coulomb gap. - Abstract: Quantum phase slip (QPS) is the topological singularity of the complex order parameter of a quasi-one-dimensional superconductor: momentary zeroing of the modulus and simultaneous 'slip' of the phase by ±2π. The QPS event(s) are the dynamic equivalent of tunneling through a conventional Josephson junction containing static in space and time weak link(s). Here we demonstrate the operation of a superconducting single electron transistor (Cooper pair transistor) without any tunnel junctions. Instead a pair of thin superconducting titanium wires in QPS regime was used. The current–voltage characteristics demonstrate the clear Coulomb blockade with magnitude of the Coulomb gap modulated by the gate potential. The Coulomb blockade disappears above the critical temperature, and at low temperatures can be suppressed by strong magnetic field.

  7. Electron Waiting Times of a Cooper Pair Splitter

    Science.gov (United States)

    Walldorf, Nicklas; Padurariu, Ciprian; Jauho, Antti-Pekka; Flindt, Christian

    2018-02-01

    Electron waiting times are an important concept in the analysis of quantum transport in nanoscale conductors. Here we show that the statistics of electron waiting times can be used to characterize Cooper pair splitters that create spatially separated spin-entangled electrons. A short waiting time between electrons tunneling into different leads is associated with the fast emission of a split Cooper pair, while long waiting times are governed by the slow injection of Cooper pairs from a superconductor. Experimentally, the waiting time distributions can be measured using real-time single-electron detectors in the regime of slow tunneling, where conventional current measurements are demanding. Our work is important for understanding the fundamental transport processes in Cooper pair splitters and the predictions may be verified using current technology.

  8. Electron Waiting Times of a Cooper Pair Splitter

    DEFF Research Database (Denmark)

    Walldorf, Nicklas; Padurariu, Ciprian; Jauho, Antti-Pekka

    2018-01-01

    Electron waiting times are an important concept in the analysis of quantum transport in nanoscale conductors. Here we show that the statistics of electron waiting times can be used to characterize Cooper pair splitters that create spatially separated spin-entangled electrons. A short waiting time...... between electrons tunneling into different leads is associated with the fast emission of a split Cooper pair, while long waiting times are governed by the slow injection of Cooper pairs from a superconductor. Experimentally, the waiting time distributions can be measured using real-time single......-electron detectors in the regime of slow tunneling, where conventional current measurements are demanding. Our work is important for understanding the fundamental transport processes in Cooper pair splitters and the predictions may be verified using current technology....

  9. Multiplying and detecting propagating microwave photons using inelastic Cooper-pair tunneling

    Science.gov (United States)

    Leppäkangas, Juha; Marthaler, Michael; Hazra, Dibyendu; Jebari, Salha; Albert, Romain; Blanchet, Florian; Johansson, Göran; Hofheinz, Max

    2018-01-01

    The interaction between propagating microwave fields and Cooper-pair tunneling across a DC-voltage-biased Josephson junction can be highly nonlinear. We show theoretically that this nonlinearity can be used to convert an incoming single microwave photon into an outgoing n -photon Fock state in a different mode. In this process, the electrostatic energy released in a Cooper-pair tunneling event is transferred to the outgoing Fock state, providing energy gain. The created multiphoton Fock state is frequency entangled and highly bunched. The conversion can be made reflectionless (impedance matched) so that all incoming photons are converted to n -photon states. With realistic parameters, multiplication ratios n >2 can be reached. By two consecutive multiplications, the outgoing Fock-state number can get sufficiently large to accurately discriminate it from vacuum with linear postamplification and power measurement. Therefore, this amplification scheme can be used as a single-photon detector without dead time.

  10. The coevolution of long-term pair bonds and cooperation.

    Science.gov (United States)

    Song, Z; Feldman, M W

    2013-05-01

    The evolution of social traits may not only depend on but also change the social structure of the population. In particular, the evolution of pairwise cooperation, such as biparental care, depends on the pair-matching distribution of the population, and the latter often emerges as a collective outcome of individual pair-bonding traits, which are also under selection. Here, we develop an analytical model and individual-based simulations to study the coevolution of long-term pair bonds and cooperation in parental care, where partners play a Snowdrift game in each breeding season. We illustrate that long-term pair bonds may coevolve with cooperation when bonding cost is below a threshold. As long-term pair bonds lead to assortative interactions through pair-matching dynamics, they may promote the prevalence of cooperation. In addition to the pay-off matrix of a single game, the evolutionarily stable equilibrium also depends on bonding cost and accidental divorce rate, and it is determined by a form of balancing selection because the benefit from pair-bond maintenance diminishes as the frequency of cooperators increases. Our findings highlight the importance of ecological factors affecting social bonding cost and stability in understanding the coevolution of social behaviour and social structures, which may lead to the diversity of biological social systems. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  11. Isominkowskian theory of Cooper Pairs in superconductors

    International Nuclear Information System (INIS)

    Animalu, A.O.E.

    1993-01-01

    Via the use of Santilli's isominkowskian space, the author presents a relativistic extension of the author's recent treatment of the Cooper Pair in superconductivity based on the Lie-isotopic lifting of quantum mechanics known as Hadronic Mechanics. The isominkowskian treatment reduces the solution of the eiganvalue problem for the quasiparticle energy spectrum to a geometric problem of specifying the metric of the isominkowskian space inside the pair in various models of ordinary high T c superconductors. The use of an intriguing realization of the metric due to Dirac reduces the dimensionality of the interior space to two yielding a spin mutation from 1/2 to zero inside a Cooper pair in two-band BCS and Hubbard models. 12 refs

  12. Shape of Cooper pairs in a norma.-metal/superconductors junction

    NARCIS (Netherlands)

    Tanaka, Yukio; Asano, Yasuhiro; Golubov, Alexandre Avraamovitch

    2008-01-01

    In s-wave superconductors the Cooper pair wave function is isotropic in momentum space. This property may also be expected for Cooper pairs entering a normal metal from a superconductor due to the proximity effect. We show, however, that such a deduction is incorrect and the pairing function in a

  13. Extra-pair mating and evolution of cooperative neighbourhoods.

    Directory of Open Access Journals (Sweden)

    Sigrunn Eliassen

    Full Text Available A striking but unexplained pattern in biology is the promiscuous mating behaviour in socially monogamous species. Although females commonly solicit extra-pair copulations, the adaptive reason has remained elusive. We use evolutionary modelling of breeding ecology to show that females benefit because extra-pair paternity incentivizes males to shift focus from a single brood towards the entire neighbourhood, as they are likely to have offspring there. Male-male cooperation towards public goods and dear enemy effects of reduced territorial aggression evolve from selfish interests, and lead to safer and more productive neighbourhoods. The mechanism provides adaptive explanations for the common empirical observations that females engage in extra-pair copulations, that neighbours dominate as extra-pair sires, and that extra-pair mating correlates with predation mortality and breeding density. The models predict cooperative behaviours at breeding sites where males cooperate more towards public goods than females. Where maternity certainty makes females care for offspring at home, paternity uncertainty and a potential for offspring in several broods make males invest in communal benefits and public goods. The models further predict that benefits of extra-pair mating affect whole nests or neighbourhoods, and that cuckolding males are often cuckolded themselves. Derived from ecological mechanisms, these new perspectives point towards the evolution of sociality in birds, with relevance also for mammals and primates including humans.

  14. Cooper-pair size and binding energy for unconventional superconducting systems

    Science.gov (United States)

    Dinóla Neto, F.; Neto, Minos A.; Salmon, Octavio D. Rodriguez

    2018-06-01

    The main proposal of this paper is to analyze the size of the Cooper pairs composed by unbalanced mass fermions from different electronic bands along the BCS-BEC crossover and study the binding energy of the pairs. We are considering an interaction between fermions with different masses leading to an inter-band pairing. In addiction to the attractive interaction we have an hybridization term to couple both bands, which in general acts unfavorable for the pairing between the electrons. We get first order phase transitions as the hybridization breaks the Cooper pairs for the s-wave symmetry of the gap amplitude. The results show the dependence of the Cooper-pair size as a function of the hybridization for T = 0 . We also propose the structure of the binding energy of the inter-band system as a function of the two-bands quasi-particle energies.

  15. Oscillation of Critical Current by Gate Voltage in Cooper Pair Transistor

    International Nuclear Information System (INIS)

    Kim, N.; Cheong, Y.; Song, W.

    2010-01-01

    We measured the critical current of a Cooper pair transistor consisting of two Josephson junctions and a gate electrode. The Cooper pair transistors were fabricated by using electron-beam lithography and double-angle evaporation technique. The Gate voltage dependence of critical current was measured by observing voltage jumps at various gate voltages while sweeping bias current. The observed oscillation was 2e-periodic, which shows the Cooper pair transistor had low level of quasiparticle poisoning.

  16. Near quantum limited amplification from inelastic Cooper-pair tunneling

    Science.gov (United States)

    Hofheinz, Max; Jebari, Salha; Blanchet, Florian; Grimm, Alexander; Hazra, Dibyendu; Albert, Romain; Portier, Fabien

    Josephson parametric amplifiers approach quantum-limited noise performance but require strong external microwave pump tones which make them more difficult to use than DC powered amplifiers: The pump tone can affect the device under test and requires expensive room-temperature equipment. Inelastic Cooper pair tunneling processes through a small DC voltage-biased Josephson junction, where a tunneling Cooper pair dissipates its energy 2 eV in the form of two photons are reminiscent of parametric down conversion. We show that these processes can be used to provide amplification near the quantum limit without external microwave pump tone. We explain the measured gain and noise based on the P (E) theory of inelastic Cooper pair tunneling and general fluctuation-dissipation relations.

  17. Cooper pair splitters beyond the Coulomb blockade regime

    Energy Technology Data Exchange (ETDEWEB)

    Amitai, Ehud; Tiwari, Rakesh P.; Nigg, Simon E. [Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel (Switzerland); Walter, Stefan [Institute for Theoretical Physics, University Erlangen Nuernberg, Staudtstrasse 7, 91058 Erlangen (Germany); Schmidt, Thomas L. [Physics and Materials Science Research Unit, University of Luxembourg, L-1511 Luxembourg (Luxembourg)

    2016-07-01

    We consider the setup of a conventional s-wave Cooper pair splitter. However, we consider the charging energies in the quantum dots to be finite and smaller than the superconducting gap. We find analytically that at low energies the superconductor mediates an inter-dot tunneling term, the spin symmetry of which is influenced by a finite Zeeman field. This effect, together with an electrical tuning scheme of the quantum dot levels, can be used to engineer a non local triplet state on the two quantum dots, thereby extending the non-local state engineering capabilities of the Cooper pair splitter system.

  18. Cooper pair splitter realized in a two-quantum-dot Y-junction.

    Science.gov (United States)

    Hofstetter, L; Csonka, S; Nygård, J; Schönenberger, C

    2009-10-15

    Non-locality is a fundamental property of quantum mechanics that manifests itself as correlations between spatially separated parts of a quantum system. A fundamental route for the exploration of such phenomena is the generation of Einstein-Podolsky-Rosen (EPR) pairs of quantum-entangled objects for the test of so-called Bell inequalities. Whereas such experimental tests of non-locality have been successfully conducted with pairwise entangled photons, it has not yet been possible to realize an electronic analogue of it in the solid state, where spin-1/2 mobile electrons are the natural quantum objects. The difficulty stems from the fact that electrons are immersed in a macroscopic ground state-the Fermi sea-which prevents the straightforward generation and splitting of entangled pairs of electrons on demand. A superconductor, however, could act as a source of EPR pairs of electrons, because its ground-state is composed of Cooper pairs in a spin-singlet state. These Cooper pairs can be extracted from a superconductor by tunnelling, but, to obtain an efficient EPR source of entangled electrons, the splitting of the Cooper pairs into separate electrons has to be enforced. This can be achieved by having the electrons 'repel' each other by Coulomb interaction. Controlled Cooper pair splitting can thereby be realized by coupling of the superconductor to two normal metal drain contacts by means of individually tunable quantum dots. Here we demonstrate the first experimental realization of such a tunable Cooper pair splitter, which shows a surprisingly high efficiency. Our findings open a route towards a first test of the EPR paradox and Bell inequalities in the solid state.

  19. The formation of Cooper pairs and the nature of superconducting currents

    International Nuclear Information System (INIS)

    Weisskopf, V.F.

    1979-12-01

    A simple physical explanation is given for the formation of Cooper pairs in a superconducting metal, for the origin of the attractive force causing the binding of the pairs, for the forming of a degenerate Bose gas by the Cooper pairs, for the finite energy gap that prevents the ensemble of electrons to change its quantum state at low temperatures, and for the existence of permanent currents in a superconducting wire. (orig.)

  20. The formation of Cooper pairs and the nature of superconducting currents

    International Nuclear Information System (INIS)

    Weisskopf, V.F.

    1981-01-01

    A simple physical explanation is given for the formation of Cooper pairs in a superconducting metal, for the origin of the attractive force causing the binding of the pairs, for the forming of a degenerate Bose gas by the Cooper pairs, for the finite energy gap that prevents the ensemble of electrons from changing its quantum state at low temperatures, and for the existence of permanent currents in a superconducting wire. (author)

  1. Enhancement of tunnel conductivity by Cooper pair fluctuations in electron-hole bilayer

    International Nuclear Information System (INIS)

    Efimkin, D K; Lozovik, Yu E

    2012-01-01

    Influence of Cooper pair fluctuations that are precursor of pairing of electrons and holes located on opposite surfaces of topological insulator film on tunnel conductivity between the surfaces is investigated. Due to restrictions caused by momentum and energy conservation dependence of tunnel conductivity on external bias voltage has peak that becomes more prominent with decreasing of disorder and temperature. We have shown that Cooper pair fluctuations considerably enhance tunneling and height of the peak diverges in vicinity of critical temperature with critical index ν = 2. Width of the peak tends to zero in proximity of critical temperature. Pairing of electrons and holes can be suppressed by disorder and in vicinity of quantum critical point height of the peak also diverges as function of Cooper pair damping with critical index μ = 2.

  2. Strong temperature effect on the sizes of the Cooper pairs in a two-band superconductor

    Science.gov (United States)

    Örd, Teet; Rägo, Küllike; Vargunin, Artjom; Litak, Grzegorz

    2018-01-01

    We study the temperature dependencies of the mean sizes of the Cooper pairs in a two-band BCS-type s-wave superconductivity model with coupling cut-off in the momentum space. It is found that, in contrast to single-band systems, the size of Cooper pairs in the weaker superconductivity band can significantly decrease with a temperature increase due to an interband proximity effect. The relevant spatial behaviour of the wave functions of the Cooper pairs is analyzed. The results also indicate a possibility that the size of Cooper pairs in two-band systems may increase with an increase in temperature.

  3. Topological Nodal Cooper Pairing in Doped Weyl Metals

    Science.gov (United States)

    Li, Yi; Haldane, F. D. M.

    2018-02-01

    We generalize the concept of Berry connection of the single-electron band structure to that of a two-particle Cooper pairing state between two Fermi surfaces with opposite Chern numbers. Because of underlying Fermi surface topology, the pairing Berry phase acquires nontrivial monopole structure. Consequently, pairing gap functions have topologically protected nodal structure as vortices in the momentum space with the total vorticity solely determined by the pair monopole charge qp. The nodes of gap function behave as the Weyl-Majorana points of the Bogoliubov-de Gennes pairing Hamiltonian. Their relation with the connection patterns of the surface modes from the Weyl band structure and the Majorana surface modes inside the pairing gap is also discussed. Under the approximation of spherical Fermi surfaces, the pairing symmetry are represented by monopole harmonic functions. The lowest possible pairing channel carries angular momentum number j =|qp|, and the corresponding gap functions are holomorphic or antiholomorphic functions on Fermi surfaces. After projected on the Fermi surfaces with nontrivial topology, all the partial-wave channels of pairing interactions acquire the monopole charge qp independent of concrete pairing mechanism.

  4. Pair bond endurance promotes cooperative food defense and inhibits conflict in coral reef butterflyfishes

    KAUST Repository

    Nowicki, Jessica; Walker, Stefan; Coker, Darren James; Hoey, Andrew; Nicolet, Katia; Pratchett, Morgan

    2017-01-01

    Pair bonding is generally linked to monogamous mating systems, where the reproductive benefits of extended mate guarding and/or of bi-parental care are considered key adaptive functions. However, in some species, including coral reef butterflyfishes (f. Chaetodonitidae), pair bonding occurs in sexually immature and homosexual partners, and in the absence of parental care, suggesting there must be non-reproductive adaptive benefits of pair bonding. Here, we examined whether pair bonding butterflyfishes cooperate in defense of food, conferring direct benefits to one or both partners. Pairs of Chaetodon lunulatus and C. baronessa use contrasting cooperative strategies. In C. lunulatus, both partners mutually defend their territory, while in C. baronessa, males prioritize territory defence; conferring improvements in feeding and energy reserves in both sexes relative to solitary counterparts. We further demonstrate that partner fidelity contributes to this function by showing that re-pairing invokes intra-pair conflict and inhibits cooperatively-derived feeding benefits, and that partner endurance is required for these costs to abate. Overall, our results suggest that in butterflyfishes, pair bonding enhances cooperative defense of prey resources, ultimately benefiting both partners by improving food resource acquisition and energy reserves.

  5. Pair bond endurance promotes cooperative food defense and inhibits conflict in coral reef butterflyfishes

    KAUST Repository

    Nowicki, Jessica P

    2017-11-14

    Pair bonding is generally linked to monogamous mating systems, where the reproductive benefits of extended mate guarding and/or of bi-parental care are considered key adaptive functions. However, in some species, including coral reef butterflyfishes (f. Chaetodonitidae), pair bonding occurs in sexually immature and homosexual partners, and in the absence of parental care, suggesting there must be non-reproductive adaptive benefits of pair bonding. Here, we examined whether pair bonding butterflyfishes cooperate in defense of food, conferring direct benefits to one or both partners. Pairs of Chaetodon lunulatus and C. baronessa use contrasting cooperative strategies. In C. lunulatus, both partners mutually defend their territory, while in C. baronessa, males prioritize territory defence; conferring improvements in feeding and energy reserves in both sexes relative to solitary counterparts. We further demonstrate that partner fidelity contributes to this function by showing that re-pairing invokes intra-pair conflict and inhibits cooperatively-derived feeding benefits, and that partner endurance is required for these costs to abate. Overall, our results suggest that in butterflyfishes, pair bonding enhances cooperative defense of prey resources, ultimately benefiting both partners by improving food resource acquisition and energy reserves.

  6. Effects of Ion Beam Irradiation on Nanoscale InOx Cooper-Pair Insulators

    Directory of Open Access Journals (Sweden)

    Srdjan Milosavljević

    2013-01-01

    Full Text Available This paper examines the effects of irradiating indium oxide films of nanoscale thickness by ion beams, when these films are in the Cooper-pair insulator state. Radiation effects are predicted on the basis of Monte Carlo simulations of ion transport. Results of numerical experiments are interpreted within the theoretical model of a Cooper-pair insulator. The study suggests that radiation-induced changes in InOx films exposed to ion beams could significantly alter their current-voltage characteristics and that a transition to a metallic state is possible, due to radiation-induced perturbation of the fine-tuned granular structure. Furthermore, incident and displaced ions can break up enough Cooper pairs in InOx films to cause dissolution of this specific insulating state.

  7. Excitons and Cooper pairs two composite bosons in many-body physics

    CERN Document Server

    Combescot, Monique

    2015-01-01

    This book bridges a gap between two major communities of Condensed Matter Physics, Semiconductors and Superconductors, that have thrived independently. Through an original perspective that their key particles, excitons and Cooper pairs, are composite bosons, the authors raise fundamental questions of current interest: how does the Pauli exclusion principle wield its power on the fermionic components of bosonic particles at a microscopic level and how this affects the macroscopic physics? What can we learn from Wannier and Frenkel excitons and from Cooper pairs that helps us understand "bosonic condensation" of composite bosons and its difference from Bose-Einstein condensation of elementary bosons? The authors start from solid mathematical and physical foundation to derive excitons and Cooper pairs. They further introduce Shiva diagrams as a graphic support to grasp the many-body physics induced by fermion exchange - a novel mechanism not visualized by standard Feynman diagrams. Advanced undergraduate or grad...

  8. Inter-layer Cooper pairing of two-dimensional electrons

    International Nuclear Information System (INIS)

    Inoue, Masahiro; Takemori, Tadashi; Yoshizaki, Ryozo; Sakudo, Tunetaro; Ohtaka, Kazuo

    1987-01-01

    The authors point out the possibility that the high transition temperatures of the recently discovered oxide superconductors are dominantly caused by the inter-layer Cooper pairing of two-dimensional electrons that are coupled through the exchange of three-dimensional phonons. (author)

  9. Generic strong coupling behavior of Cooper pairs in the surface of superfluid nuclei

    International Nuclear Information System (INIS)

    Pillet, N.; Sandulescu, N.; Schuck, P.

    2007-01-01

    With realistic HFB calculations, using the D1S Gogny force, we reveal a generic behavior of concentration of small sized Cooper pairs (2-3 fm) in the surface of superfluid nuclei. This study confirms and extends previous results given in the literature that use more schematic approaches. It is shown that the strong concentration of pair probability of small Cooper pairs in the nuclear surface is a quite general and generic feature and that nuclear pairing is much closer to the strong coupling regime than previously assumed

  10. Generic strong coupling behavior of Cooper pairs in the surface of superfluid nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Pillet, N. [DPTA/Service de Physique nucleaire, CEA/DAM Ile de France, BP12, F-91680 Bruyeres-le-Chatel (France); Sandulescu, N. [DPTA/Service de Physique nucleaire, CEA/DAM Ile de France, BP12, F-91680 Bruyeres-le-Chatel (France)]|[Institute of Physics and Nuclear Engineering, 76900 Bucharest (Romania)]|[Institut de Physique Nucleaire, CNRS, UMR 8608, Orsay, F-91406 (France); Schuck, P. [Institut de Physique Nucleaire, CNRS, UMR 8608, Orsay, F-91406 (France)]|[Universite Paris-Sud, Orsay, F-91505 (France)

    2007-01-15

    With realistic HFB calculations, using the D1S Gogny force, we reveal a generic behavior of concentration of small sized Cooper pairs (2-3 fm) in the surface of superfluid nuclei. This study confirms and extends previous results given in the literature that use more schematic approaches. It is shown that the strong concentration of pair probability of small Cooper pairs in the nuclear surface is a quite general and generic feature and that nuclear pairing is much closer to the strong coupling regime than previously assumed.

  11. Creation of Spin-Triplet Cooper Pairs in the Absence of Magnetic Ordering

    Science.gov (United States)

    Breunig, Daniel; Burset, Pablo; Trauzettel, Björn

    2018-01-01

    In superconducting spintronics, it is essential to generate spin-triplet Cooper pairs on demand. Up to now, proposals to do so concentrate on hybrid structures in which a superconductor (SC) is combined with a magnetically ordered material (or an external magnetic field). We, instead, identify a novel way to create and isolate spin-triplet Cooper pairs in the absence of any magnetic ordering. This achievement is only possible because we drive a system with strong spin-orbit interaction—the Dirac surface states of a strong topological insulator (TI)-out of equilibrium. In particular, we consider a bipolar TI-SC-TI junction, where the electrochemical potentials in the outer leads differ in their overall sign. As a result, we find that nonlocal singlet pairing across the junction is completely suppressed for any excitation energy. Hence, this junction acts as a perfect spin-triplet filter across the SC, generating equal-spin Cooper pairs via crossed Andreev reflection.

  12. Unconventional Cooper pairing results in a pseudogap-like phase in s-wave superconductors

    International Nuclear Information System (INIS)

    Springer, Daniel; Cheong, Siew Ann

    2015-01-01

    The impact of disorder on the superconducting (SC) pairing mechanism is the centre of much debate. Some evidence suggests a loss of phase coherence of pairs while others point towards the formation of a competing phase. In our work we show that the two perspectives may be different sides of the same coin. Using an extension of the perturbative renormalization group approach we compare the impact of different disorder-induced interactions on a SC ground state. We find that in the strongly disordered regime an interaction between paired fermions and their respective disordered environment replaces conventional Cooper pairing. For these unconventional Cooper pairs the phase coherence condition, required for the formation of a SC condensate, is not satisfied. (paper)

  13. Collective neutrino-pair emission due to Cooper pairing of protons in superconducting neutron stars

    International Nuclear Information System (INIS)

    Leinson, L.B.

    2001-01-01

    The neutrino emission due to formation and breaking of Cooper pairs of protons in superconducting cores of neutron stars is considered with taking into account the electromagnetic coupling of protons to ambient electrons. It is shown that collective response of electrons to the proton quantum transition contributes coherently to the complete interaction with a neutrino field and enhances the neutrino-pair production. Our calculation shows that the contribution of the vector weak current to the ννbar emissivity of protons is much larger than that calculated by different authors without taking into account the plasma effects. Partial contribution of the pairing protons to the total neutrino radiation from the neutron star core is very sensitive to the critical temperatures for the proton and neutron pairing. We show domains of these parameters where the neutrino radiation, caused by a singlet-state pairing of protons is dominating

  14. Bound states and Cooper pairs of molecules in 2D optical lattices bilayer

    Energy Technology Data Exchange (ETDEWEB)

    Camacho-Guardian, A.; Dominguez-Castro, G.A.; Paredes, R. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico (Mexico)

    2016-08-15

    We investigate the formation of Cooper pairs, bound dimers and the dimer-dimer elastic scattering of ultracold dipolar Fermi molecules confined in a 2D optical lattice bilayer configuration. While the energy and their associated bound states are determined in a variational way, the correlated two-molecule pair is addressed as in the original Cooper formulation. We demonstrate that the 2D lattice confinement favors the formation of zero center mass momentum bound states. Regarding the Cooper pairs binding energy, this depends on the molecule populations in each layer. Maximum binding energies occur for non-zero (zero) pair momentum when the Fermi system is polarized (unpolarized). We find an analytic expression for the dimer-dimer effective interaction in the deep BEC regime. The present analysis represents a route for addressing the BCS-BEC crossover in dipolar Fermi gases confined in 2D optical lattices within the current experimental panorama. (copyright 2016 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. Dynamical Cooper pairing in non-equilibrium electron-phonon systems

    Energy Technology Data Exchange (ETDEWEB)

    Knap, Michael [Technical University of Munich (Germany); Harvard University (United States); Babadi, Mehrtash; Refael, Gil [Caltech (United States); Martin, Ivar [Argonne National Laboratory (United States); Demler, Eugene [Harvard University (United States)

    2016-07-01

    Ultrafast laser pulses have been used to manipulate complex quantum materials and to induce dynamical phase transitions. One of the most striking examples is the transient enhancement of superconductivity in several classes of materials upon irradiating them with high intensity pulses of terahertz light. Motivated by these experiments we analyze the Cooper pairing instabilities in non-equilibrium electron-phonon systems. We demonstrate that the light induced non-equilibrium state of phonons results in a simultaneous increase of the superconducting coupling constant and the electron scattering. We analyze the competition between these effects and show that in a broad range of parameters the dynamic enhancement of Cooper pair formation dominates over the increase in the scattering rate. This opens the possibility of transient light induced superconductivity at temperatures that are considerably higher than the equilibrium transition temperatures. Our results pave new pathways for engineering high-temperature light-induced superconducting states.

  16. On the combination of the Cooper pair and the Ogg pair in the high-Tc oxide superconductor

    International Nuclear Information System (INIS)

    Zhang Liyuan.

    1991-08-01

    In this paper it is argued that the superconductivity of the high-T c oxide superconductor (HTOS) can be explained by the combinating mechanism of the Cooper pair and the Ogg pair. The properties of the superconducting state of the HTOS have been calculated under this mechanism, and the theoretical results are overall consistent with the experiment. (author). 37 refs

  17. High frequency of extra-pair paternity in an urban population of Cooper's Hawks

    Science.gov (United States)

    Rosenfield, Robert N.; Sonsthagen, Sarah A.; Stout, William C.; Talbot, Sandra L.

    2015-01-01

    Raptors exhibit some of the highest rates of intra-pair copulations among birds, perhaps in an attempt by males to reduce the risk of being cuckolded. Indeed, the frequency of extra-pair fertilizations reported in studies of raptors to date is relatively low (0-11.2%). Socially monogamous Cooper's Hawks (Accipiter cooperii) exhibit one of the highest copulation rates among birds, yet there are no published accounts of extra-pair copulations (or paternity). We studied a population of Cooper's Hawks in Milwaukee, Wisconsin, during three breeding seasons (2003, 2004, and 2007), examining the possible effects of age (1 yr old vs. ≥ 2 yr old), adult mass, and brood size on the frequency of extra-pair paternity (EPP). We found that 19.3% of nestlings (N = 27/140) were extra-pair young (EPY), and 34% of all broods (N = 15/44) had at least one EPY. The sires of the EPY in our study were identified for only two broods, suggesting that floater males may have engaged in extra-pair copulations with territorial females. We found that brood size was a good predictor of the occurrence of EPP (EPP) in nests, but adult mass and female age were not. To our knowledge, these possible correlates of the occurrence of EPP in raptors had not previously been investigated. Male Cooper's Hawks provide food for females during the pre-nesting period, and delivery of food is, in contrast to other raptor species, typically followed by copulation. Thus, one possible explanation of the relatively high rates of EPP in our study is that females might accept or even solicit extra-pair copulations from males other than their mates as a means of maximizing energy intake for egg production. Such behavior might be particularly likely in our study area, i.e., a food-rich urban setting with a high breeding density of Cooper's Hawks.

  18. Alpha-transfer reactions and the pairing-vibration model

    International Nuclear Information System (INIS)

    Betts, R.R.

    1977-01-01

    The pairing-vibration model with isospin is extended to include α-transfer reactions. Selection rules and expressions for transition strengths are derived and compared with experimental results for A = 40--66 nuclei. The selection rules are found to be followed quite well in the examples studied. The systematics of ground-state transition strengths are qualitatively quite well reproduced although the quantitative agreement is poor. When the changing nature of the pairing quanta is incorporated using two-particle transfer data the agreement becomes quantitatively good. Evidence is presented for clustering other than that due to pairing in 40 Ca and 44 Ti

  19. Nonlocal Cooper pair splitting in a pSn-junction

    NARCIS (Netherlands)

    Veldhorst, M.; Brinkman, Alexander

    2010-01-01

    Perfect Cooper pair splitting is proposed, based on crossed Andreev reflection (CAR) in a p-type semiconductor-superconductor-n-type semiconductor (pSn) junction. The ideal splitting is caused by the energy filtering that is enforced by the band structure of the electrodes. The pSn junction is

  20. Cooperation arrangements related to technology transfer

    International Nuclear Information System (INIS)

    Eysel, G.

    1986-04-01

    A developing country which considers to launch a nuclear program should put as much as possible efforts to elaborate a program which suits the country's needs as well as reflects its capabilities. It deems advantageous that a developing country makes use of the experience and knowledge in the nuclear field of a partner country already in the phase when exploring the technical and commercial aspects of a nuclear power program. For the different stages of cooperation between two countries a three-level concept appears advisable for establishing the basis for individual cooperation agreement. The first level are agreements between the governments of both countries on joint scientific research projects and technical development programs covering a broad spectrum of activities not limited to the energy sector. At the second level cooperation agreements can already concentrate on the energy sector and e.g. specifically investigate the energy structure of the developing country. If this investigation results in the decision of the developing country to establish a nuclear power program the next level will cover a broad based cooperation in the nuclear field including a large number of different cooperation contracts in various fields. In this stage of bilateral cooperation the main emphasis will be put on industrial cooperation. Cooperation agreements to be concluded between respective partners of both countries may cover fields related to research and development, engineering of a nuclear power plant, manufacturing of its components, erection and installation as well as operation of the plant. The most common agreements refer to technical cooperation, which covers not only the transfer of blueprints but also training of the recipient's personnel in the partner's country and delegation of experts to the recipient's country. The most comprehensive form of cooperation is the foundation of a joint venture company where the technology partner does not only transfer his know

  1. Understanding Fomalhaut as a Cooper pair

    Science.gov (United States)

    Feng, F.; Jones, H. R. A.

    2018-03-01

    Fomalhaut is a nearby stellar system and has been found to be a triple based on astrometric observations. With new radial velocity and astrometric data, we study the association between Fomalhaut A, B, and C in a Bayesian framework, finding that the system is gravitationally bound or at least associated. Based on simulations of the system, we find that Fomalhaut C can be easily destabilized through combined perturbations from the Galactic tide and stellar encounters. Considering that observing the disruption of a triple is probably rare in the solar neighbourhood, we conclude that Fomalhaut C is a so-called `gravitational pair' of Fomalhaut A and B. Like the Cooper pair mechanism in superconductors, this phenomenon only appears once the orbital energy of a component becomes comparable with the energy fluctuations caused by the environment. Based on our simulations, we find (1) an upper limit of 8 km s-1 velocity difference is appropriate when selecting binary candidates, and (2) an empirical formula for the escape radius, which is more appropriate than tidal radius when measuring the stability of wide binaries.

  2. Possibility of Cooper-pair formation controlled by multi-terminal spin injection

    Science.gov (United States)

    Ohnishi, K.; Sakamoto, M.; Ishitaki, M.; Kimura, T.

    2018-03-01

    A multi-terminal lateral spin valve consisting of three ferromagnetic nanopillars on a Cu/Nb bilayer has been fabricated. We investigated the influence of the spin injection on the superconducting properties at the Cu/Nb interface. The non-local spin valve signal exhibits a clear spin insulation signature due to the superconducting gap of the Nb. The magnitude of the spin signal is found to show the probe configuration dependence. From the careful analysis of the bias current dependence, we found the suppression of the superconductivity due to the exchange interaction between the Cooper pair and accumulated spin plays an important role in the multi-terminal spin injections. We also discuss about the possibility of the Cooper-pair formation due to the spin injection from the two injectors with the anti-parallel alignment.

  3. Magnetic Field Tuning and Quantum Interference in a Cooper Pair Splitter.

    Science.gov (United States)

    Fülöp, G; Domínguez, F; d'Hollosy, S; Baumgartner, A; Makk, P; Madsen, M H; Guzenko, V A; Nygård, J; Schönenberger, C; Levy Yeyati, A; Csonka, S

    2015-11-27

    Cooper pair splitting (CPS) is a process in which the electrons of the naturally occurring spin-singlet pairs in a superconductor are spatially separated using two quantum dots. Here, we investigate the evolution of the conductance correlations in an InAs CPS device in the presence of an external magnetic field. In our experiments the gate dependence of the signal that depends on both quantum dots continuously evolves from a slightly asymmetric Lorentzian to a strongly asymmetric Fano-type resonance with increasing field. These experiments can be understood in a simple three-site model, which shows that the nonlocal CPS leads to symmetric line shapes, while the local transport processes can exhibit an asymmetric shape due to quantum interference. These findings demonstrate that the electrons from a Cooper pair splitter can propagate coherently after their emission from the superconductor and how a magnetic field can be used to optimize the performance of a CPS device. In addition, the model calculations suggest that the estimate of the CPS efficiency in the experiments is a lower bound for the actual efficiency.

  4. Universal quantum gates for Single Cooper Pair Box based quantum computing

    Science.gov (United States)

    Echternach, P.; Williams, C. P.; Dultz, S. C.; Braunstein, S.; Dowling, J. P.

    2000-01-01

    We describe a method for achieving arbitrary 1-qubit gates and controlled-NOT gates within the context of the Single Cooper Pair Box (SCB) approach to quantum computing. Such gates are sufficient to support universal quantum computation.

  5. Probing the pairing interaction through two-neutron transfer reactions

    Directory of Open Access Journals (Sweden)

    Margueron J.

    2012-12-01

    Full Text Available The treatment of the pairing interaction in mean-field-based models is addressed. In particular, the possibility to use pair transfers as A tool to better constrain this interaction is discussed. First, pairing inter-actions with various density dependencies (surface/volume mixing are used in the microscopic Hartree-Fock-Bogoliubov + quasiparticle random-phase approximation model to generate the form factors to be used in reaction calculations. Cross sections for (p,t two-neutron transfer reactions are calculated in the one-step zero-range distorted-wave Born approximation for some Tin isotopes and for incident proton energies from 15 to 35 MeV. Three different surface/volume mixings of A zero-range density-dependent pairing interaction are employed in the microscopic calculations and the sensitivity of the cross sections to the different mixings is analyzed. Differences among the three different theoretical predictions are found espacially for the nucleus 136Sn and they are more important at the incident proton energy of 15 MeV. We thus indicate (p,t two-neutron transfer reactions with very neutron-rich Sn isotopes and at proton energies around 15 MeV as good experimental cases where the surface/volume mixing of the pairing interaction may be probed. In the second part of the manuscript, ground-state to ground-state transitions are investigated. Approximations made to estimate two-nucleon transfer probabilities in ground-state to ground-state transitions and the physical interpretation of these probabilities are discussed. Probabilities are often calculated by approximating both ground states of the initial nucleus A and of the final nucleus A±2 by the same quasiparticle vacuum. We analyze two improvements of this approach. First, the effect of using two different ground states with average numbers of particles A and A±2 is quantified. Second, by using projection techniques, the role of particle number restoration is analyzed. Our analysis

  6. Knowledge transfer in pair programming: An in-depth analysis

    DEFF Research Database (Denmark)

    Plonka, Laura; Sharp, Helen; van der Linden, Janet

    2015-01-01

    Whilst knowledge transfer is one of the most widely-claimed benefits of pair programming, little is known about how knowledge transfer is achieved in this setting. This is particularly pertinent for novice−expert constellations, but knowledge transfer takes place to some degree in all constellati...

  7. On the possibility of observing experimentally diabolic pair transfer in rotating nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Canto, L F; Donangelo, R; Nikam, R S; Ring, P

    1987-06-25

    We investigate the cross section for two-nucleon transfer reactions to rotational states by heavy projectiles. In particular we study the influence of the recently predicted unexpected behavior of the diabolic pair transfer amplitude. Dramatic reduction of the probabilities for two-nucleon transfer in connection with inelastic Coulomb excitation are found in the angular momentum region, where the pair transfer matrix element changes its sign.

  8. How to measure the cooper pair mass using plasmons in low-dimensional superconductor structures

    International Nuclear Information System (INIS)

    Mishonov, T.M.

    1990-06-01

    The creation of the Cooper pair mass-spectroscopy is suggested. The plasmons in low-dimensional superconductor structures (layers or wires in dielectric background) are theoretically considered to that purpose. The Cooper pair mass m * can be determined by measurements of the Doppler shift of the plasmon frequency when a direct current is applied through the superconductor. The plasmons with frequency ω lower than the superconducting gap 2 Δ can be detected by the same fare-infrared (FIR) absorption technique and grating couplings used previously for investigation of two-dimension (2D) plasmons in semiconductor microstructures. (author). 17 refs, 2 figs

  9. Technology transfer and the Argentina-German cooperation agreement

    International Nuclear Information System (INIS)

    Di Primio, J.C.

    1977-01-01

    The transfer of technology from developed countries is usually done through industrial enterprises. The local industrialization of imported technology does not necessary imply that full benefit is extracted from its application. A pre-established scientific and technical infrastructure is needed to understand and incorporate it, and to develop methods for improvement and use at the industrial level, in the frame of national conditions. The transference of nuclear technology has shown recently new concepts for the implementation. It is becoming a rule that massive industrial nuclear technology transfer to developing nations is conditioned by the latter requirement for simulataneous assistance to create or promote that infrastructure. An example of international cooperation to meet the requirement explained above is the Argentine-German agreement for the peaceful applications of nuclear energy. Since 1971 it has been used to strengthen the scientific and technical programs of the Argentine Atomic Energy Commission, by application to fields relevant by its industrial implications. The objectives and implementation of the agreement are described: cooperative actions where initially directed to the infrastructure needed to support the nuclear fuel cycle industry. The results achieved during the period 1971-76 are critically analyzed. This analysis has influenced the selection of future cooperative projects as well as the extension of the cooperation to other nuclear fields of common interest [es

  10. PCTFPeval: a web tool for benchmarking newly developed algorithms for predicting cooperative transcription factor pairs in yeast.

    Science.gov (United States)

    Lai, Fu-Jou; Chang, Hong-Tsun; Wu, Wei-Sheng

    2015-01-01

    Computational identification of cooperative transcription factor (TF) pairs helps understand the combinatorial regulation of gene expression in eukaryotic cells. Many advanced algorithms have been proposed to predict cooperative TF pairs in yeast. However, it is still difficult to conduct a comprehensive and objective performance comparison of different algorithms because of lacking sufficient performance indices and adequate overall performance scores. To solve this problem, in our previous study (published in BMC Systems Biology 2014), we adopted/proposed eight performance indices and designed two overall performance scores to compare the performance of 14 existing algorithms for predicting cooperative TF pairs in yeast. Most importantly, our performance comparison framework can be applied to comprehensively and objectively evaluate the performance of a newly developed algorithm. However, to use our framework, researchers have to put a lot of effort to construct it first. To save researchers time and effort, here we develop a web tool to implement our performance comparison framework, featuring fast data processing, a comprehensive performance comparison and an easy-to-use web interface. The developed tool is called PCTFPeval (Predicted Cooperative TF Pair evaluator), written in PHP and Python programming languages. The friendly web interface allows users to input a list of predicted cooperative TF pairs from their algorithm and select (i) the compared algorithms among the 15 existing algorithms, (ii) the performance indices among the eight existing indices, and (iii) the overall performance scores from two possible choices. The comprehensive performance comparison results are then generated in tens of seconds and shown as both bar charts and tables. The original comparison results of each compared algorithm and each selected performance index can be downloaded as text files for further analyses. Allowing users to select eight existing performance indices and 15

  11. Theory of superconductivity. II. Excited Cooper pairs. Why does sodium remain normal down to 0 K?

    International Nuclear Information System (INIS)

    Fujita, S.

    1992-01-01

    Based on a generalized BCS Hamiltonian in which the interaction strengths (V 11 , V 22 , V 12 ) among and between electron (12) and hole (2) Cooper pairs are differentiated, the thermodynamic properties of a type-I superconductor below the critical temperature T c are investigated. An expression for the ground-state energy, W - W 0 , relative to the unperturbed Block system is obtained. The usual BCS formulas are obtained in the limits: (all) V jl = V 0 , N 1 (0) = N 2 (0). Any excitations generated through the BCS interaction Hamiltonian containing V jl must involve Cooper pairs of antiparallel spins and nearly opposite momenta. The nonzero momentum or excited Cooper pairs below T c are shown to have an excitation energy band minimum lower than the quasi-electrons, which were regarded as the elementary excitations in the original BCS theory. The energy gap var-epsilon g (T) defined relative to excited and zero-momentum Copper pairs (when V jl > 0) decreases from var-epsilon g (0) to 0 as the temperature T is raised from 0 to T c . If electrons only are available as in a monovalent metal like sodium (V 12 = 0), the energy constant Δ 1 is finite but the energy gap vanishes identically for all T. In agreement with the BCS theory, the present theory predicts that a pure nonmagnetic metal in any dimensions should have a Cooper-pair ground state whose energy is lower than that of the Bloch ground state. Additionally it predicts that a monovalent metal should remain normal down to 0 K, and that there should be no strictly one-dimensional superconductor

  12. Structural change of cooper pairs in color superconductivity. Crossover from weak coupling to strong coupling

    Energy Technology Data Exchange (ETDEWEB)

    Abuki, Hiroaki; Hatsuda, Tetsuo [Tokyo Univ., Dept. of Physics, Tokyo (Japan); Itakura, Kazunori [Brookhaven National Laboratory, RIKEN BNL Research Center, Upton, NY (United States)

    2002-09-01

    The two-flavor color superconductivity is studied over a wide range of baryon density with a single model. We pay a special attention to the spatial-momentum dependence of the gap and to the spatial-structure of Cooper pairs. At extremely high baryon density ({approx}O(10{sup 10} {rho}{sub 0}) with {rho}{sub 0} being the normal nuclear matter density), our model becomes equivalent to the usual perturbative QCD treatment and the gap is shown to have a sharp peak near the Fermi surface due to the weak-coupling nature of QCD. On the other hand, the gap is a smooth function of the momentum at lower densities ({approx}O(10{sup 10} {rho}{sub 0})) due to strong color magnetic and electric interactions. To study the structural change of Cooper pairs from high density to lower density, quark correlation in the color superconductor is studied both in the momentum space and in the coordinate space. The size of the Cooper pair is shown to become comparable to the averaged inter-quark distance at low densities. Also, effects of the momentum-dependent running coupling and the antiquark pairing, which are both small at high density, are shown to be non-negligible at low densities. These features are highly contrasted to the standard BCS superconductivity in metals. (author)

  13. International co-operation and the transfer of nuclear technology

    International Nuclear Information System (INIS)

    di Primio, J.C.

    1977-01-01

    The transfer of technology from developed countries is usually done through industrial enterprises. The local industrialization of imported technology does not necessarily imply that full benefit is extracted from its application. A pre-established scientific and technical infrastructure is needed to understand and incorporate it, and to develop methods for improvement and use at the industrial level, in the frame of national conditions. The transference of nuclear technology has recently shown new concepts for implementation. It is becoming a rule that massive industrial nuclear technology transfer to developing nations is tied to a requirement for simultaneous assistance in creating or promoting the infrastructure. An example of international co-operation to meet this requirement is the Argentine-German Agreement for the Peaceful Applications of Nuclear Energy. Since 1971 this has been used to strengthen the scientific and technical programmes of the Argentine Atomic Energy Commission in the relevant fields of industrial applications. The objectives and implementation of the agreement are described: co-operative actions were initially directed to the infrastructure needed to support the nuclear fuel cycle industry. The results achieved during the period 1971-1976 are critically analysed. This analysis has influenced the selection of future co-operative projects as well as the extension of the co-operation to other nuclear fields of common interest. (author)

  14. Cooperative heat transfer and ground coupled storage system

    Science.gov (United States)

    Metz, P.D.

    A cooperative heat transfer and ground coupled storage system wherein collected solar heat energy is ground stored and permitted to radiate into the adjacent ground for storage therein over an extended period of time when such heat energy is seasonally maximally available. Thereafter, when said heat energy is seasonally minimally available and has propagated through the adjacent ground a substantial distance, the stored heat energy may be retrieved by a circumferentially arranged heat transfer means having a high rate of heat transfer.

  15. Approach to equilibrium in a pure superconductor. The relaxation of the Cooper pair density

    Energy Technology Data Exchange (ETDEWEB)

    Schid, A

    1968-01-01

    Electron-phonon and electron-electron collisions are the processes which determine the relaxation time r/sub R/ of the Cooper pair density. The case is considered for which the deviation of the pair density from equilibrium is small and where the equilibrium state is homogeneous. Starting from the Eliashberg equation one is able to reduce the problem to a quadrature once the equilibrium Green functions are known.

  16. Quasiparticle density of states in a half metal in the presence of odd-frequency Cooper pairs

    NARCIS (Netherlands)

    Asano, Yasuhiro; Yokoyama, Takehito; Tanaka, Yukio; Golubov, Alexandre Avraamovitch

    2008-01-01

    We study the local density of states in a half metal sandwiched by the two superconductors. The spin-flip scattering at the junction interface opens the Josephson channels of the odd-frequency spin-triplet s-wave Cooper pairs. The penetration of the odd-frequency pairs enhances the quasiparticle

  17. Cooper Pair Writing at the LaAlO3/ SrTiO 3 Interface

    Science.gov (United States)

    Cen, Cheng; Bogorin, Daniela F.; Bark, Chung Wung; Folkman, Chad M.; Eom, Chang-Beom; Levy, Jeremy

    2011-03-01

    Superconducting semiconductors offer unique ways to exert electrostatic control over macroscopic quantum phases. The recently demonstrated nanoscale control over conductivity at the LaAl O3 / SrTi O3 interface raises the question of whether nanoscale control over superconducting phases can be realized. Here we report low-temperature magnetotransport experiments on structures defined with nanoscale precision at the LaAl O3 / SrTi O3 interface. A quantum phase transition is observed that is associated with the formation of Cooper pairs, but a finite resistance is observed at the lowest temperatures. Higher mobility interfaces exhibit larger Ginsburg-Landau coherence lengths, a stronger suppression of pairing by magnetic field as well as Shubnikov-de Haas oscillations. Cooper pair localization, spin-orbit coupling, and finite-size effects may factor into an explanation for some of the unusual properties observed. The work is supported by Department of Energy and State of Florida, NSF (DMR-0906443 and DMR-0704022), DOE (DE-FG02-06ER46327) and the Fine Foundation.

  18. Cooperative interactions between paired domain and homeodomain.

    Science.gov (United States)

    Jun, S; Desplan, C

    1996-09-01

    The Pax proteins are a family of transcriptional regulators involved in many developmental processes in all higher eukaryotes. They are characterized by the presence of a paired domain (PD), a bipartite DNA binding domain composed of two helix-turn-helix (HTH) motifs,the PAI and RED domains. The PD is also often associated with a homeodomain (HD) which is itself able to form homo- and hetero-dimers on DNA. Many of these proteins therefore contain three HTH motifs each able to recognize DNA. However, all PDs recognize highly related DNA sequences, and most HDs also recognize almost identical sites. We show here that different Pax proteins use multiple combinations of their HTHs to recognize several types of target sites. For instance, the Drosophila Paired protein can bind, in vitro, exclusively through its PAI domain, or through a dimer of its HD, or through cooperative interaction between PAI domain and HD. However, prd function in vivo requires the synergistic action of both the PAI domain and the HD. Pax proteins with only a PD appear to require both PAI and RED domains, while a Pax-6 isoform and a new Pax protein, Lune, may rely on the RED domain and HD. We propose a model by which Pax proteins recognize different target genes in vivo through various combinations of their DNA binding domains, thus expanding their recognition repertoire.

  19. Drive the Dirac electrons into Cooper pairs in SrxBi2Se3

    Science.gov (United States)

    Du, Guan; Shao, Jifeng; Yang, Xiong; Du, Zengyi; Fang, Delong; Wang, Jinghui; Ran, Kejing; Wen, Jinsheng; Zhang, Changjin; Yang, Huan; Zhang, Yuheng; Wen, Hai-Hu

    2017-01-01

    Topological superconductors are a very interesting and frontier topic in condensed matter physics. Despite the tremendous efforts in exploring topological superconductivity, its presence is however still under heavy debate. The Dirac electrons have been proven to exist on the surface of a topological insulator. It remains unclear whether and how the Dirac electrons fall into Cooper pairing in an intrinsic superconductor with the topological surface states. Here we show the systematic study of scanning tunnelling microscope/spectroscopy on the possible topological superconductor SrxBi2Se3. We first demonstrate that only the intercalated Sr atoms can induce superconductivity. Then we show the full superconducting gaps without any in-gap density of states as expected theoretically for a bulk topological superconductor. Finally, we find that the surface Dirac electrons will simultaneously condense into the superconducting state within the superconducting gap. This vividly demonstrates how the surface Dirac electrons are driven into Cooper pairs. PMID:28198378

  20. Study of neutron-proton pairing in N=Z unstable nuclei through transfer reactions

    International Nuclear Information System (INIS)

    Le Crom, B.

    2016-01-01

    A nucleus is described as a set of independent neutrons and protons linked by a mean-field potential. However, in order to have a better description one needs to take into account some residual interactions such as pairing. Neutron-neutron and proton-proton pairings are well-studied but neutron-proton pairing is not well-known. np pairing can be isovector pairing such as nn and pp pairing or isoscalar which is yet unknown. Over-binding of N=Z nuclei could be a manifestation of np pairing. We have studied np pairing through transfer reactions. In this case, the cross-section of np pair transfer is expected to be enhanced in the presence of important np pairing. np pairing is expected to be important in N=Z nuclei with high J orbitals. Since the development of radioactive beam facilities, such beams are only available. The experiment was performed at GANIL with an efficient set-up so as to detect products from the (p, 3 He) transfer reaction. This reaction is affected by isovector and isoscalar np pairing. We used 56 Ni and 52 Fe beams so as to see the effect of the occupancy of 0f 7/2 shell on the np pairing. First, we analysed the data from the 56 Ni(p,d) 55 Ni reaction and we compared the results with the literature to validate analysis procedure. After analysing data from the 56 Ni(p, 3 He) 54 Co reaction and extracting the population of the various states of 54 Co, we obtained information about the relative intensity between isoscalar and isovector np pairing in 56 Ni showing the predominance of isovector np pairing in this nucleus. Moreover, in the framework of developing a new charged particle detector, research on the discrimination of light nuclei using pulse shape analysis was performed and is also presented. (author)

  1. Cooper pairs' magnetic moment in MCFL color superconductivity

    International Nuclear Information System (INIS)

    Feng Bo; Ferrer, Efrain J.; Incera, Vivian de la

    2011-01-01

    We investigate the effect of the alignment of the magnetic moments of Cooper pairs of charged quarks that form at high density in three-flavor quark matter. The high-density phase of this matter in the presence of a magnetic field is known to be the Magnetic Color-Flavor-Locked (MCFL) phase of color superconductivity. We derive the Fierz identities of the theory and show how the explicit breaking of the rotational symmetry by the uniform magnetic field opens new channels of interactions and allows the formation of a new diquark condensate. The new order parameter is a spin-1 condensate proportional to the component in the field direction of the average magnetic moment of the pairs of charged quarks. The magnitude of the spin-1 condensate becomes comparable to the larger of the two scalar gaps in the region of large fields. The existence of the spin-1 condensate is unavoidable, as in the presence of a magnetic field there is no solution of the gap equations with nonzero scalar gaps and zero magnetic moment condensate. This is consistent with the fact that the extra condensate does not break any symmetry that has not already been broken by the known MCFL gaps. The spin-1 condensate enhances the condensation energy of pairs formed by charged quarks and the magnetization of the system. We discuss the possible consequences of the new order parameter on the issue of the chromomagnetic instability that appears in color superconductivity at moderate density.

  2. Technology transfer: A cooperative agreement and success story

    International Nuclear Information System (INIS)

    Reno, H.W.; McNeel, K.; Armstrong, A.T.; Vance, J.K.

    1996-01-01

    This paper describes the cooperative agreement between the U.S. Department of Energy and Envirocare of Utah, Inc., wherein the former transferred macroencapsulative technology to the latter for purposes of demonstrating commercialization of treatment and disposal of 225, 000 Kg of radioactive lead stored at departmental installations

  3. Sensitivity of Electron Transfer Mediated Decay to Ion Pairing.

    Science.gov (United States)

    Pohl, Marvin N; Richter, Clemens; Lugovoy, Evgeny; Seidel, Robert; Slavíček, Petr; Aziz, Emad F; Abel, Bernd; Winter, Bernd; Hergenhahn, Uwe

    2017-08-17

    Ion pairing in electrolyte solutions remains a topic of discussion despite a long history of research. Very recently, nearest-neighbor mediated electronic de-excitation processes of core hole vacancies (electron transfer mediated decay, ETMD) were proposed to carry a spectral fingerprint of local solvation structure and in particular of contact ion pairs. Here, for the first time, we apply electron-electron coincidence detection to a liquid microjet, and record ETMD spectra of Li 1s vacancies in aqueous solutions of lithium chloride (LiCl) in direct comparison to lithium acetate (LiOAc). A change in the ETMD spectrum dependent on the electrolyte anion identity is observed for 4.5 M salt concentration. We discuss these findings within the framework of the formation and presence of contact ion pairs and the unique sensitivity of ETMD spectroscopy to ion pairing.

  4. A quantitative study of quasiparticle traps using the single-Cooper-pair-transistor

    OpenAIRE

    Court, N. A.; Ferguson, A. J.; Lutchyn, Roman; Clark, R. G.

    2007-01-01

    We use radio-frequency reflectometry to measure quasiparticle tunneling rates in the single-Cooper-pair-transistor. Devices with and without quasiparticle traps in proximity to the island are studied. A $10^2$ to $10^3$-fold reduction in the quasiparticle tunneling rate onto the island is observed in the case of quasiparticle traps. In the quasiparticle trap samples we also measure a commensurate decrease in quasiparticle tunneling rate off the island.

  5. Theoretical study on the cooperative exciton dissociation process based on dimensional and hot charge-transfer state effects in an organic photocell

    International Nuclear Information System (INIS)

    Shimazaki, Tomomi; Nakajima, Takahito

    2016-01-01

    This paper discusses the exciton dissociation process at the donor–acceptor interface in organic photocells. In our previous study, we introduced a local temperature to handle the hot charge-transfer (CT) state and calculated the exciton dissociation probability based on the 1D organic semiconductor model [T. Shimazaki and T. Nakajima, Phys. Chem. Chem. Phys. 17, 12538 (2015)]. Although the hot CT state plays an essential role in exciton dissociations, the probabilities calculated are not high enough to efficiently separate bound electron–hole pairs. This paper focuses on the dimensional (entropy) effect together with the hot CT state effect and shows that cooperative behavior between both effects can improve the exciton dissociation process. In addition, we discuss cooperative effects with site-disorders and external-electric-fields.

  6. Gamow-Teller transitions and neutron-proton-pair transfer reactions

    Science.gov (United States)

    Van Isacker, P.; Macchiavelli, A. O.

    2018-05-01

    We propose a schematic model of nucleons moving in spin-orbit partner levels, j = l ± 1/2, to explain Gamow-Teller and two-nucleon transfer data in N = Z nuclei above 40Ca. Use of the LS coupling scheme provides a more transparent approach to interpret the structure and reaction data. We apply the model to the analysis of charge-exchange, 42Ca(3He,t)42Sc, and np-transfer, 40Ca(3He,p)42Sc, reactions data to define the elementary modes of excitation in terms of both isovector and isoscalar pairs, whose properties can be determined by adjusting the parameters of the model (spin-orbit splitting, isovector pairing strength and quadrupole matrix element) to the available data. The overall agreement with experiment suggests that the approach captures the main physics ingredients and provides the basis for a boson approximation that can be extended to heavier nuclei. Our analysis also reveals that the SU(4)-symmetry limit is not realized in 42Sc.

  7. Cooperative spin decoherence and population transfer

    International Nuclear Information System (INIS)

    Genes, C.; Berman, P. R.

    2006-01-01

    An ensemble of multilevel atoms is a good candidate for a quantum information storage device. The information is encrypted in the collective ground state atomic coherence, which, in the absence of external excitation, is decoupled from the vacuum and therefore decoherence free. However, in the process of manipulation of atoms with light pulses (writing, reading), one inadvertently introduces a coupling to the environment, i.e., a source of decoherence. The dissipation process is often treated as an independent process for each atom in the ensemble, an approach which fails at large atomic optical depths where cooperative effects must be taken into account. In this paper, the cooperative behavior of spin decoherence and population transfer for a system of two, driven multilevel atoms is studied. Not surprisingly, an enhancement in the decoherence rate is found, when the atoms are separated by a distance that is small compared to an optical wavelength; however, it is found that this rate increases even further for somewhat larger separations for atoms aligned along the direction of the driving field's propagation vector. A treatment of the cooperative modification of optical pumping rates and an effect of polarization swapping between atoms is also discussed, lending additional insight into the origin of the collective decay

  8. Pengaruh Pendekatan Cooperative Learning Tipe (TPS Think, Pair, and Share Terhadap Hasil Belajar PKn di Sekolah Dasar

    Directory of Open Access Journals (Sweden)

    Sulistyani Puteri Ramadhani

    2017-12-01

    Full Text Available Tujuan penelitian ini adalah untuk mengetahui pengaruh penggunaan pendekatan cooperative learning tipe think, pair, and share terhadap hasil belajar PKn pada siswa kelas V sekolah dasar. Penelitian ini dilaksanakan di SDN Kebon Baru 10 Pagi dengan sampel penelitian siswa kelas V pada semester II tahun pelajaran 2016-2017. Sampel penelitian menggunakan teknik Simple Random Sampling. Penelitian ini menggunakan metode eksperimen. Adapun teknik pengumpulan data dilakukan menggunakan lembar tes yang dilakukan setelah materi pembelajaran diberikan lembar tes untuk mengetahui hasil belajar PKn siswa, yang sebelumnya telah dilakukan pengujian validitas dan reliabilitas dengan justifikasi ahli dan dianalisis dengan uji normalitas dan uji homogenitas baik kelas kontrol maupun kelas eksperimen. Hasil pengujian normalitas menunjukan bahwa kedua kelas berdistribusi normal. Hasil pengujian homogenitas menunjukan bahwa kedua kelas tersebut homogen. Setelah dilakukan uji persyaratan analisis, maka dilakukan uji hipotesis dengan perhitungan uji-t. Berdasarkan hasil perhitungan uji-t maka hipotesis nol (Ho ditolak dan hipotesis kerja (H1 diterima. Dari perhitungan tersebut maka dapat disimpulkan bahwa penggunaan pendekatan cooperative learning tipe think, pair, and share berpengaruh signifikan terhadap hasil belajar PKn pada siswa kelas V sekolah dasar. Implikasi hasil penelitian ini adalah penggunaan pendekatan cooperative learning tipe think, pair, and share pada pembelajaran PKn dapat  diterapkan guru agar dapat meningkatkan hasil belajar siswa.

  9. Nuclear squid: Diabolic pair transfer in rotating nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Nikam, R S; Ring, P; Canto, L F

    1987-02-19

    A new unexpected behavior of pair transfer matrix elements in superfluid rotating nuclei is predicted. With increasing angular velocity they drop to zero, change their sign and in some cases even oscillate between positive and negative values. This effect is related to diabolical points in rotating quasiparticle spectra and is closely analogous to the DC-Josephson effect in superconductors in the presence of a magnetic field.

  10. Cooper pair formation dynamics in Bi2Sr2CaCu2O8+δ

    International Nuclear Information System (INIS)

    Kaindl, R.A.; Carnahan, M.A.; Orenstein, J.; Chemla, D.S.; Oh, S.; Eckstein, J.N.

    2003-01-01

    We utilize ultrafast terahertz pulses to monitor the carrier dynamics in the high-TC superconductor Bi2Sr2CaCu2O8+delta. The temperature, density and time dependence distinctly exposes a bimolecular recombination process of quasiparticles which underlies formation of Cooper pairs

  11. The Effectiveness of Cooperative Learning Model of Pair Checks Type on Motivation and Mathematics Learning Outcomes of 8th Grade Junior High School Students

    Directory of Open Access Journals (Sweden)

    Wahyu Budi Wicaksono

    2017-08-01

    Full Text Available The purpose of this research was to know the effectiveness of Pair Checks cooperative model towards students’ learning result and learning motivation of eight grade. Population of this research were students of eight grade Junior High School 2 Pati in the academic year 2016/1017. The research used cluster random sampling technique.Where the selected samples were students of class VIII H as experimental class and class VIII G as control class. The data collected by the method of documentation, test methods, and scale methods. The analyzed of data used completeness test and average different test. The results showed that: (1 students’ learning result who join Pair Checks cooperative model have classical study completeness; (2 students’ mathematics learning result who join Pair Checks cooperative model is better than students mathematics learning result who join ekspository learning; (3 students’ learning motivation who join Pair Checks cooperative model is better than students’ learning motivation who join ekspository learning.

  12. Skill Learning and Skill Transfer Mediated by Cooperative Haptic Interaction.

    Science.gov (United States)

    Avila Mireles, Edwin Johnatan; Zenzeri, Jacopo; Squeri, Valentina; Morasso, Pietro; De Santis, Dalia

    2017-07-01

    It is known that physical coupling between two subjects may be advantageous in joint tasks. However, little is known about how two people mutually exchange information to exploit the coupling. Therefore, we adopted a reversed, novel perspective to the standard one that focuses on the ability of physically coupled subjects to adapt to cooperative contexts that require negotiating a common plan: we investigated how training in pairs on a novel task affects the development of motor skills of each of the interacting partners. The task involved reaching movements in an unstable dynamic environment using a bilateral non-linear elastic tool that could be used bimanually or dyadically. The main result is that training with an expert leads to the greatest performance in the joint task. However, the performance in the individual test is strongly affected by the initial skill level of the partner. Moreover, practicing with a peer rather than an expert appears to be more advantageous for a naive; and motor skills can be transferred to a bimanual context, after training with an expert, only if the non-expert subject had prior experience of the dynamics of the novel task.

  13. Microscopic description of pair transfer between two superfluid Fermi systems: Combining phase-space averaging and combinatorial techniques

    Science.gov (United States)

    Regnier, David; Lacroix, Denis; Scamps, Guillaume; Hashimoto, Yukio

    2018-03-01

    In a mean-field description of superfluidity, particle number and gauge angle are treated as quasiclassical conjugated variables. This level of description was recently used to describe nuclear reactions around the Coulomb barrier. Important effects of the relative gauge angle between two identical superfluid nuclei (symmetric collisions) on transfer probabilities and fusion barrier have been uncovered. A theory making contact with experiments should at least average over different initial relative gauge-angles. In the present work, we propose a new approach to obtain the multiple pair transfer probabilities between superfluid systems. This method, called phase-space combinatorial (PSC) technique, relies both on phase-space averaging and combinatorial arguments to infer the full pair transfer probability distribution at the cost of multiple mean-field calculations only. After benchmarking this approach in a schematic model, we apply it to the collision 20O+20O at various energies below the Coulomb barrier. The predictions for one pair transfer are similar to results obtained with an approximated projection method, whereas significant differences are found for two pairs transfer. Finally, we investigated the applicability of the PSC method to the contact between nonidentical superfluid systems. A generalization of the method is proposed and applied to the schematic model showing that the pair transfer probabilities are reasonably reproduced. The applicability of the PSC method to asymmetric nuclear collisions is investigated for the 14O+20O collision and it turns out that unrealistically small single- and multiple pair transfer probabilities are obtained. This is explained by the fact that relative gauge angle play in this case a minor role in the particle transfer process compared to other mechanisms, such as equilibration of the charge/mass ratio. We conclude that the best ground for probing gauge-angle effects in nuclear reaction and/or for applying the proposed

  14. Modeling the cooperative energy transfer dynamics of quantum cutting for solar cells

    NARCIS (Netherlands)

    Rabouw, Freddy T.; Meijerink, Andries

    2015-01-01

    Cooperative energy transfer (ET) is a quantum cutting (or downconversion) process where a luminescent center splits its excited state energy in two by simultaneous transfer to two nearby acceptor centers, thus yielding two low-energy photons for each high-energy photon absorbed. It has the potential

  15. Arrays of Cooper pair boxes coupled to a superconducting reservoir: 'superradiance' and 'revival'

    International Nuclear Information System (INIS)

    Rodrigues, D A; Gyoerffy, B L; Spiller, T P

    2004-01-01

    We consider an array of l b Cooper pair boxes, each of which is coupled to a superconducting reservoir by a capacitive tunnel junction. We discuss two effects that probe not just the quantum nature of the islands, but also of the superconducting reservoir coupled to them. These are analogues to the well-known quantum optical effects 'superradiance' and 'revival'. When revival is extended to multiple systems, we find that 'entanglement revival' can also be observed. In order to study the above effects, we utilize a highly simplified model for these systems in which all the single-electron energy eigenvalues are set to be the same (the strong coupling limit), as are the charging energies of the Cooper pair boxes, allowing the whole system to be represented by two coupled quantum spins, one finite, which represents the array of boxes, and one representing the reservoir, which we consider in the limit of infinite size. Although this simplification is drastic, the model retains the main features necessary to capture the phenomena of interest. Given the progress in superconducting box experiments over recent years, it is possible that experiments to investigate both of these interesting quantum coherent phenomena could be performed in the foreseeable future

  16. Quantitative Raman Measurement of the Evolution of the Cooper-pair Density with Doping in Bi2Sr2CaCu2O8+δ Superconductors

    International Nuclear Information System (INIS)

    Blanc, S.; Gu, G.; Gallais, Y.; Sacuto, A.; Cazayous, M.; Measson, M.A.; Wen, J.S.; Xu, Z.J.

    2009-01-01

    We report Raman measurements on Bi 2 Sr 2 CaCu 2 O 8+δ single crystals that allow us to quantitatively evaluate the doping dependence of the density of Cooper pairs in the superconducting state. We show that the drastic loss of Cooper pairs in the antinodal region as the doping level is reduced is concomitant with a deep alteration of the quasiparticles dynamic above T c and consistent with a pseudogap that competes with superconductivity. Our data also reveal that the overall density of Cooper pairs evolves with doping, distinctly from the superfluid density above the doping level p c = 0.2.

  17. A Bethe ansatz solvable model for superpositions of Cooper pairs and condensed molecular bosons

    International Nuclear Information System (INIS)

    Hibberd, K.E.; Dunning, C.; Links, J.

    2006-01-01

    We introduce a general Hamiltonian describing coherent superpositions of Cooper pairs and condensed molecular bosons. For particular choices of the coupling parameters, the model is integrable. One integrable manifold, as well as the Bethe ansatz solution, was found by Dukelsky et al. [J. Dukelsky, G.G. Dussel, C. Esebbag, S. Pittel, Phys. Rev. Lett. 93 (2004) 050403]. Here we show that there is a second integrable manifold, established using the boundary quantum inverse scattering method. In this manner we obtain the exact solution by means of the algebraic Bethe ansatz. In the case where the Cooper pair energies are degenerate we examine the relationship between the spectrum of these integrable Hamiltonians and the quasi-exactly solvable spectrum of particular Schrodinger operators. For the solution we derive here the potential of the Schrodinger operator is given in terms of hyperbolic functions. For the solution derived by Dukelsky et al., loc. cit. the potential is sextic and the wavefunctions obey PT-symmetric boundary conditions. This latter case provides a novel example of an integrable Hermitian Hamiltonian acting on a Fock space whose states map into a Hilbert space of PT-symmetric wavefunctions defined on a contour in the complex plane

  18. Positive cooperativity of the specific binding between Hg2+ ion and T:T mismatched base pairs in duplex DNA

    International Nuclear Information System (INIS)

    Torigoe, Hidetaka; Miyakawa, Yukako; Ono, Akira; Kozasa, Tetsuo

    2012-01-01

    Highlights: ► Hg 2+ specifically bound with the T:T mismatched base pair at 1:1 molar ratio. ► The binding constant between Hg 2+ and the T:T mismatched base pair was 10 6 M −1 . ► The binding constant was larger than those for nonspecific metal–DNA interactions. ► The binding constant for the second Hg 2+ was larger than that for the first Hg 2+ . ► The positive cooperative binding was observed between Hg 2+ and multiple T:T. - Abstract: Metal-mediated base pairs by the interaction between metal ions and artificial bases in oligonucleotides have been developed for their potential applications in nanotechnology. We recently found that a natural T:T mismatched base pair bound with Hg 2+ ion to form a novel T–Hg–T base pair. Here, we examined the thermodynamic properties of the binding between Hg 2+ and each of the single and double T:T mismatched base pair duplex DNAs by isothermal titration calorimetry. Hg 2+ specifically bound with the T:T mismatched base pair at 1:1 molar ratio with 10 6 M −1 binding constant, which was significantly larger than those for nonspecific metal ion–DNA interactions. In the Hg 2+ –double T:T mismatched base pair interaction, the affinity for the second Hg 2+ binding was significantly larger than that for the first Hg 2+ binding. The positively cooperative binding may be favorable to align multiple Hg 2+ in duplex DNA for the application of the metal-mediated base pairs in nanotechnology.

  19. Technology transfer and knowledge management in cooperation networks: the Airzone case

    International Nuclear Information System (INIS)

    Benavides Velasco, C. A.; Quintana Garcia, C.

    2007-01-01

    This paper highlights the importance of cooperation networks between the public system of R and D and industry to promote technology transfer, knowledge management, and the consolidation and growth of new technology firms. Through the case of Air zone,his paper shows the significance of collaboration agreements between University and industry to enhance technology transfer and the success of entrepreneurial projects. (Author) 28 refs

  20. Siemens technology transfer and cooperation in the nuclear fuel area

    International Nuclear Information System (INIS)

    Holley, H.-P.; Fuchs, J. H.; Rothenbuecher, R. A.

    1997-01-01

    Siemens is a full-range supplier in the area of nuclear power generation with broad experience and activities in the field of nuclear fuel. Siemens has developed advanced fuel technology for all types fuel assemblies used throughout the world and has significant experience worldwide in technology transfer in the field of nuclear fuel. Technology transfer and cooperation has ranged between the provision of mechanical design advice for a specific fuel design and the erection of complete fabrication plants for commercial operation in 3 countries. In the following the wide range of Siemens' technology transfer activities for both fuel design and fuel fabrication technologies are shown

  1. Possible evidence for spin-transfer torque induced by spin-triplet supercurrent

    KAUST Repository

    Li, Lailai

    2017-10-04

    Cooper pairs in superconductors are normally spin singlet. Nevertheless, recent studies suggest that spin-triplet Cooper pairs can be created at carefully engineered superconductor-ferromagnet interfaces. If Cooper pairs are spin-polarized they would transport not only charge but also a net spin component, but without dissipation, and therefore minimize the heating effects associated with spintronic devices. Although it is now established that triplet supercurrents exist, their most interesting property - spin - is only inferred indirectly from transport measurements. In conventional spintronics, it is well known that spin currents generate spin-transfer torques that alter magnetization dynamics and switch magnetic moments. The observation of similar effects due to spin-triplet supercurrents would not only confirm the net spin of triplet pairs but also pave the way for applications of superconducting spintronics. Here, we present a possible evidence for spin-transfer torques induced by triplet supercurrents in superconductor/ferromagnet/superconductor (S/F/S) Josephson junctions. Below the superconducting transition temperature T_c, the ferromagnetic resonance (FMR) field at X-band (~ 9.0 GHz) shifts rapidly to a lower field with decreasing temperature due to the spin-transfer torques induced by triplet supercurrents. In contrast, this phenomenon is absent in ferromagnet/superconductor (F/S) bilayers and superconductor/insulator/ferromagnet/superconductor (S/I/F/S) multilayers where no supercurrents pass through the ferromagnetic layer. These experimental observations are discussed with theoretical predictions for ferromagnetic Josephson junctions with precessing magnetization.

  2. Cooper pair induced frustration and nematicity of two-dimensional magnetic adatom lattices

    Science.gov (United States)

    Schecter, Michael; Syljuâsen, Olav F.; Paaske, Jens

    2018-05-01

    We propose utilizing the Cooper pair to induce magnetic frustration in systems of two-dimensional (2D) magnetic adatom lattices on s -wave superconducting surfaces. The competition between singlet electron correlations and the RKKY coupling is shown to lead to a variety of hidden-order states that break the point-group symmetry of the 2D adatom lattice at finite temperature. The phase diagram is constructed using a newly developed effective bond theory [M. Schecter et al., Phys. Rev. Lett. 119, 157202 (2017), 10.1103/PhysRevLett.119.157202], and exhibits broad regions of long-range vestigial nematic order.

  3. Pair and single neutron transfer with Borromean 8He

    International Nuclear Information System (INIS)

    Lemasson, A.; Navin, A.; Rejmund, M.; Keeley, N.; Zelevinsky, V.; Bhattacharyya, S.; Shrivastava, A.; Bazin, D.; Beaumel, D.; Blumenfeld, Y.; Chatterjee, A.; Gupta, D.; France, G. de; Jacquot, B.; Labiche, M.; Lemmon, R.; Nanal, V.; Nyberg, J.; Pillay, R.G.; Raabe, R.

    2011-01-01

    Direct observation of the survival of 199 Au residues after 2n transfer in the 8 He+ 197 Au system and the absence of the corresponding 67 Cu in the 8 He+ 65 Cu system at various energies are reported. The measurements of the surprisingly large cross sections for 199 Au, coupled with the integral cross sections for the various Au residues, is used to obtain the first model-independent lower limits on the ratio of 2n to 1n transfer cross sections from 8 He to a heavy target. A comparison of the transfer cross sections for 6,8 He on these targets highlights the differences in the interactions of these Borromean nuclei. These measurements for the most neutron-rich nuclei on different targets highlight the need to probe the reaction mechanism with various targets and represent an experimental advance towards understanding specific features of pairing in the dynamics of dilute nuclear systems.

  4. Splitting efficiency and interference effects in a Cooper pair splitter based on a triple quantum dot with ferromagnetic contacts

    Science.gov (United States)

    Bocian, Kacper; Rudziński, Wojciech; Weymann, Ireneusz

    2018-05-01

    We theoretically study the spin-resolved subgap transport properties of a Cooper pair splitter based on a triple quantum dot attached to superconducting and ferromagnetic leads. Using the Keldysh Green's function formalism, we analyze the dependence of the Andreev conductance, Cooper pair splitting efficiency, and tunnel magnetoresistance on the gate and bias voltages applied to the system. We show that the system's transport properties are strongly affected by spin dependence of tunneling processes and quantum interference between different local and nonlocal Andreev reflections. We also study the effects of finite hopping between the side quantum dots on the Andreev current. This allows for identifying the optimal conditions for enhancing the Cooper pair splitting efficiency of the device. We find that the splitting efficiency exhibits a nonmonotonic dependence on the degree of spin polarization of the leads and the magnitude and type of hopping between the dots. An almost perfect splitting efficiency is predicted in the nonlinear response regime when the energies of the side quantum dots are tuned to the energies of the corresponding Andreev bound states. In addition, we analyzed features of the tunnel magnetoresistance (TMR) for a wide range of the gate and bias voltages, as well as for different model parameters, finding the corresponding sign changes of the TMR in certain transport regimes. The mechanisms leading to these effects are thoroughly discussed.

  5. Regional Cooperation Agreement for Asia and the Pacific (RCA). A mechanism for nuclear technology transfer

    International Nuclear Information System (INIS)

    Bin Muslim, N.

    1993-01-01

    The paper presents the regional cooperation programs of the IAEA which have as purpose to promote the applications of peaceful uses of atomic energy and to transfer technology to the developing countries. The paper focusses on the (RCA) program for Asia and the Pacific, it is considered the most important mechanism for genuine technology transfer. The annex no 1 lists the full text of the Regional Cooperative Agreement for Research, Development and Training Related to Nuclear Science and Technology, 1987 (13 articles). The annex no.3 lists also the full text of the African Regional Cooperative Agreement for Research, Development and training Related to Nuclear Science and Technology (14 articles). 11 refs., 17 tabs

  6. The story of technical cooperation

    International Nuclear Information System (INIS)

    Park, Yang Taek

    1989-09-01

    This book gives descriptions of technical cooperation, which is about why does technology transfer?, process of technology transfer with model, decisive cause and cooperation of technology transfer, cost and effect of technology transfer, historical experience of technology transfer, cases of technology transfer by field such as rubber tire, medicine and computer industry and automobile industry, technology transfer process and present condition of technical cooperation, and strategy for rising of technical cooperation : selection of technology for object of cooperation and development of human resources.

  7. Correlation-induced suppression of decoherence in capacitively coupled Cooper-pair boxes

    Science.gov (United States)

    Hu, Xuedong; You, J. Q.; Nori, Franco

    2005-03-01

    Charge fluctuations from gate bias and background traps severely limit the performance of a charge qubit in a Cooper-pair box (CPB). Here we discuss an encoding approachootnotetextJ.Q. You, X.Hu, and F. Nori, cond-mat/0407423. to control the decoherence effects of these charge fluctuations using two strongly capacitively coupled CPBs. This coupled-box system has a low-decoherence subspace of two states, for which we calculate the dephasing and relaxation rates using a master equation approach. Our results show that the inter-box Coulomb correlation can significantly suppress decoherence of this two-level system by reducing the strength of the system-environment interaction, making it a promising candidate as a logical qubit, encoded using two CPBs.

  8. Effects of stimulus pair orientation and hand switching on reaction time estimates of interhemispheric transfer.

    Science.gov (United States)

    Leblanc-Sirois, Yanick; Braun, Claude M J; Elie-Fortier, Jonathan

    2018-03-26

    Two behavioral estimates of interhemispheric transfer time, the crossed-uncrossed difference (CUD) and the unilateral field advantage (UFA), are thought to, respectively, index transfer of premotor and visual information across the corpus callosum in neurotypical participants. However, no attempt to manipulate visual and motor contingencies in a set of tasks while measuring the CUD and the UFA has yet been reported. In two go/no-go comparison experiments, stimulus pair orientations were manipulated. The hand of response changed after each correct response in the second, but not the first experiment. No correlation was found between the CUD and the UFA, supporting the hypothesis that these two measures index different types of information transfer across hemispheres. An effect of manipulation of stimulus pair orientation on UFAs was attributed to the homotopy of callosal fibers transferring visual information, while an effect of hand switching on CUDs was attributed mostly to spatial compatibility.

  9. Cooperative activation of cardiac transcription through myocardin bridging of paired MEF2 sites

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Courtney M. [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Hu, Jianxin [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Thomas, Reuben [Univ. of California, San Francisco, CA (United States). Gladstone Inst.; Gainous, T. Blair [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Celona, Barbara [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Sinha, Tanvi [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Dickel, Diane E. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Genomics Division; Heidt, Analeah B. [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Xu, Shan-Mei [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Bruneau, Benoit G. [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Univ. of California, San Francisco, CA (United States). Gladstone Inst.; Pollard, Katherine S. [Univ. of California, San Francisco, CA (United States). Gladstone Inst.; Pennacchio, Len A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Genomics Division; Black, Brian L. [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Univ. of California, San Francisco, CA (United States). Dept. of

    2017-03-28

    Enhancers frequently contain multiple binding sites for the same transcription factor. These homotypic binding sites often exhibit synergy, whereby the transcriptional output from two or more binding sites is greater than the sum of the contributions of the individual binding sites alone. Although this phenomenon is frequently observed, the mechanistic basis for homotypic binding site synergy is poorly understood. Here in this paper, we identify a bona fide cardiac-specific Prkaa2 enhancer that is synergistically activated by homotypic MEF2 binding sites. We show that two MEF2 sites in the enhancer function cooperatively due to bridging of the MEF2C-bound sites by the SAP domain-containing co-activator protein myocardin, and we show that paired sites buffer the enhancer from integration site-dependent effects on transcription in vivo. Paired MEF2 sites are prevalent in cardiac enhancers, suggesting that this might be a common mechanism underlying synergy in the control of cardiac gene expression in vivo.

  10. Coherent Cooper pair tunneling in systems of Josephson junctions: effects of quasiparticle tunneling and of the electromagnetic environment

    NARCIS (Netherlands)

    Maassen van den Brink, A.; Odintsov, A.A.; Bobbert, P.A.; Schön, G.

    1991-01-01

    Small capacitance tunnel junctions show single electron effects and, in the superconducting state, the coherent tunneling of Cooper pairs. We study these effects in a system of two Josephson junctions, driven by a voltage source with a finite impedance. Novel features show up in theI–V

  11. A cavity-Cooper pair transistor scheme for investigating quantum optomechanics in the ultra-strong coupling regime

    International Nuclear Information System (INIS)

    Rimberg, A J; Blencowe, M P; Armour, A D; Nation, P D

    2014-01-01

    We propose a scheme involving a Cooper pair transistor (CPT) embedded in a superconducting microwave cavity, where the CPT serves as a charge tunable quantum inductor to facilitate ultra-strong coupling between photons in the cavity and a nano- to meso-scale mechanical resonator. The mechanical resonator is capacitively coupled to the CPT, such that mechanical displacements of the resonator cause a shift in the CPT inductance and hence the cavity's resonant frequency. The amplification provided by the CPT is sufficient for the zero point motion of the mechanical resonator alone to cause a significant change in the cavity resonance. Conversely, a single photon in the cavity causes a shift in the mechanical resonator position on the order of its zero point motion. As a result, the cavity-Cooper pair transistor coupled to a mechanical resonator will be able to access a regime in which single photons can affect single phonons and vice versa. Realizing this ultra-strong coupling regime will facilitate the creation of non-classical states of the mechanical resonator, as well as the means to accurately characterize such states by measuring the cavity photon field. (paper)

  12. Microscopic calculation of absolute values of two-nucleon transfer cross sections

    International Nuclear Information System (INIS)

    Potel, G.; Bayman, B. F.; Barranco, F.

    2009-01-01

    Arguably, the greatest achievement of many-body physics in the fifties was that of providing the basis for a complete description and a thorough understanding of superconductivity in metals. At the basis of it one finds BCS theory and Josephson effect. The first recognized the central role played by the appearance of a macroscopic coherent field -usually viewed as a condensate of strongly overlapping Cooper pairs-, the quasiparticle vacuum. The second realized that a true gap is not essential for such a state of matter to exist, but rather a finite expectation value of the pair field. Consequently, the specific probe to study the superconducting state is Cooper pair tunneling. Important progress in the understanding of pairing in atomic nuclei may arise from the systematic study of two-particle transfer reactions. Although this subject of research started about the time of the BCS papers, the quantitative calculation of absolute cross sections taking properly into account the full non-locality of the Cooper pairs (correlation length much larger than nuclear dimensions) is still an open problem. We present in this talk the results obtained within a second order DWBA framework for two- nucleon transfer reactions around the Coulomb barrier induced both by heavy and light ions. The calculations were done using a computer code developed for this purpose including the sequential and simultaneous contributions to the process, with microscopic form factors which take into account the relevant structure aspects of the process, such as the nature of the single-particle wavefunctions, the spectroscopic factors, and the interaction potential responsible for the transfer. Reasonable agreement with the experimental absolute values of the differential cross section is obtained without any parameter adjustment (see Figure 1).(author)

  13. Atomic-scale Visualization of Electronic Nematicity and Cooper Pairing in Iron-based Superconductors

    Science.gov (United States)

    Allan, Milan P.

    2013-03-01

    The mechanism of high-temperature superconductivity in the relatively novel iron-based high-Tc superconductors is unresolved, both in terms of how the phases evolve with doping, and in terms of the actual Cooper pairing process. To explore these issues, we used spectroscopic-imaging scanning tunneling microscopy to study the electronic structure of CaFe2As2 in the antiferromagnetic-orthorhombic `parent' state from which the superconductivity emerges. We discovered and visualized the now widely studied electronic `nematicity' of this phase, whose suppression is associated with the emergence of superconductivity (Science 327, 181, 2010). As subsequent transport experiments discovered a related anisotropic conductance which increases with dopant concentration, the interplay between the electronic structure surrounding each dopant atom, quasiparticle scattering therefrom, and the transport nematicity has become a pivotal focus of research. We find that substituting Co for Fe atoms in underdoped Ca(Fe1-xCox)2As2 generates a dense population of identical and strongly anisotropic impurity states that are distributed randomly but aligned with the antiferromagnetic a-axis. We also demonstrate, by imaging their surrounding interference patterns, that these impurity states scatter quasiparticles and thus influence transport in a highly anisotropic manner (M.P. Allan et al., 2013). Next, we studied the momentum dependence of the energy gaps of iron-based superconductivity, now focusing on LiFeAs. If strong electron-electron interactions mediate the Cooper pairing, then momentum-space anisotropic superconducting energy gaps Δi (k) were predicted by multiple techniques to appear on the different electronic bands i. We introduced intraband Bogoliubov quasiparticle scattering interference (QPI) techniques for the determination of anisotropic energy gaps to test these hypotheses and discovered the anisotropy, magnitude, and relative orientations of the energy gaps on multiple

  14. Controlling the transmitted information of a multi-photon interacting with a single-Cooper pair box

    International Nuclear Information System (INIS)

    Kadry, Heba; Abdel-Aty, Abdel-Haleem; Zakaria, Nordin; Cheong, Lee Yen

    2014-01-01

    We study a model of a multi-photon interaction of a single Cooper pair box with a cavity field. The exchange of the information using this system is studied. We quantify the fidelity of the transmitted information. The effect of the system parameters (detuning parameter, field photons, state density and mean photon number) in the fidelity of the transmitted information is investigated. We found that the fidelity of the transmitted information can be controlled using the system parameters

  15. Controlling the transmitted information of a multi-photon interacting with a single-Cooper pair box

    Energy Technology Data Exchange (ETDEWEB)

    Kadry, Heba, E-mail: hkadry1@yahoo.com; Abdel-Aty, Abdel-Haleem, E-mail: hkadry1@yahoo.com; Zakaria, Nordin, E-mail: hkadry1@yahoo.com [Computer and Information Science Department, Universiti Teknologi Petronas, Seri Iskandar, 31750 Tronoh, Perak (Malaysia); Cheong, Lee Yen [Fundamental and Applied Science Department, Universiti Teknologi Petronas, Seri Iskandar, 31750 Tronoh, Perak (Malaysia)

    2014-10-24

    We study a model of a multi-photon interaction of a single Cooper pair box with a cavity field. The exchange of the information using this system is studied. We quantify the fidelity of the transmitted information. The effect of the system parameters (detuning parameter, field photons, state density and mean photon number) in the fidelity of the transmitted information is investigated. We found that the fidelity of the transmitted information can be controlled using the system parameters.

  16. Electron and Cooper-pair transport across a single magnetic molecule explored with a scanning tunneling microscope

    Science.gov (United States)

    Brand, J.; Gozdzik, S.; Néel, N.; Lado, J. L.; Fernández-Rossier, J.; Kröger, J.

    2018-05-01

    A scanning tunneling microscope is used to explore the evolution of electron and Cooper-pair transport across single Mn-phthalocyanine molecules adsorbed on Pb(111) from tunneling to contact ranges. Normal-metal as well as superconducting tips give rise to a gradual transition of the Bardeen-Cooper-Schrieffer energy gap in the tunneling range into a zero-energy resonance close to and at contact. Supporting transport calculations show that in the normal-metal-superconductor junctions this resonance reflects the merging of in-gap Yu-Shiba-Rusinov states as well as the onset of Andreev reflection. For the superconductor-superconductor contacts, the zero-energy resonance is rationalized in terms of a finite Josephson current that is carried by phase-dependent Andreev and Yu-Shiba-Rusinov levels.

  17. Current cross-correlations in double quantum dot Cooper pair splitter

    Energy Technology Data Exchange (ETDEWEB)

    Wrzesniewski, Kacper; Trocha, Piotr; Weymann, Ireneusz [Faculty of Physics, Adam Mickiewicz University, 61-614 Poznan (Poland)

    2016-07-01

    We investigate theoretically transport properties of a quantum dot (QD) system working as a Cooper pair splitter. The device is coupled to one superconducting and two ferromagnetic leads. Presented results are calculated using real-time diagrammatic technique in the sequential tunneling approximation with respect to the coupling to ferromagnetic leads. The transport properties are evaluated within the superconductor subgap regime taking into account Andreev reflection processes solely. We focus on the analysis of current and current cross-correlations, both in linear and nonlinear responses. Current cross-correlations give additional information about dynamics of transport processes. We identify both positive and negative signs of current cross-correlations and discuss mechanisms leading to those results. Strong negative cross-correlations are found when the occupation number of QD system becomes degenerate and near the emergence of the triplet blockade, while positive ones occur in the most range where current flows due to crossed Andreev processes. Finally, we consider ferromagnetic leads polarization and temperature influences on aforementioned features.

  18. Transition from Sign-Reversed to Sign-Preserved Cooper-Pairing Symmetry in Sulfur-Doped Iron Selenide Superconductors.

    Science.gov (United States)

    Wang, Qisi; Park, J T; Feng, Yu; Shen, Yao; Hao, Yiqing; Pan, Bingying; Lynn, J W; Ivanov, A; Chi, Songxue; Matsuda, M; Cao, Huibo; Birgeneau, R J; Efremov, D V; Zhao, Jun

    2016-05-13

    An essential step toward elucidating the mechanism of superconductivity is to determine the sign or phase of the superconducting order parameter, as it is closely related to the pairing interaction. In conventional superconductors, the electron-phonon interaction induces attraction between electrons near the Fermi energy and results in a sign-preserved s-wave pairing. For high-temperature superconductors, including cuprates and iron-based superconductors, prevalent weak coupling theories suggest that the electron pairing is mediated by spin fluctuations which lead to repulsive interactions, and therefore that a sign-reversed pairing with an s_{±} or d-wave symmetry is favored. Here, by using magnetic neutron scattering, a phase sensitive probe of the superconducting gap, we report the observation of a transition from the sign-reversed to sign-preserved Cooper-pairing symmetry with insignificant changes in T_{c} in the S-doped iron selenide superconductors K_{x}Fe_{2-y}(Se_{1-z}S_{z})_{2}. We show that a rather sharp magnetic resonant mode well below the superconducting gap (2Δ) in the undoped sample (z=0) is replaced by a broad hump structure above 2Δ under 50% S doping. These results cannot be readily explained by simple spin fluctuation-exchange pairing theories and, therefore, multiple pairing channels are required to describe superconductivity in this system. Our findings may also yield a simple explanation for the sometimes contradictory data on the sign of the superconducting order parameter in iron-based materials.

  19. Entropy Transfer between Residue Pairs and Allostery in Proteins: Quantifying Allosteric Communication in Ubiquitin.

    Directory of Open Access Journals (Sweden)

    Aysima Hacisuleyman

    2017-01-01

    Full Text Available It has recently been proposed by Gunasakaran et al. that allostery may be an intrinsic property of all proteins. Here, we develop a computational method that can determine and quantify allosteric activity in any given protein. Based on Schreiber's transfer entropy formulation, our approach leads to an information transfer landscape for the protein that shows the presence of entropy sinks and sources and explains how pairs of residues communicate with each other using entropy transfer. The model can identify the residues that drive the fluctuations of others. We apply the model to Ubiquitin, whose allosteric activity has not been emphasized until recently, and show that there are indeed systematic pathways of entropy and information transfer between residues that correlate well with the activities of the protein. We use 600 nanosecond molecular dynamics trajectories for Ubiquitin and its complex with human polymerase iota and evaluate entropy transfer between all pairs of residues of Ubiquitin and quantify the binding susceptibility changes upon complex formation. We explain the complex formation propensities of Ubiquitin in terms of entropy transfer. Important residues taking part in allosteric communication in Ubiquitin predicted by our approach are in agreement with results of NMR relaxation dispersion experiments. Finally, we show that time delayed correlation of fluctuations of two interacting residues possesses an intrinsic causality that tells which residue controls the interaction and which one is controlled. Our work shows that time delayed correlations, entropy transfer and causality are the required new concepts for explaining allosteric communication in proteins.

  20. Entropy Transfer between Residue Pairs and Allostery in Proteins: Quantifying Allosteric Communication in Ubiquitin.

    Science.gov (United States)

    Hacisuleyman, Aysima; Erman, Burak

    2017-01-01

    It has recently been proposed by Gunasakaran et al. that allostery may be an intrinsic property of all proteins. Here, we develop a computational method that can determine and quantify allosteric activity in any given protein. Based on Schreiber's transfer entropy formulation, our approach leads to an information transfer landscape for the protein that shows the presence of entropy sinks and sources and explains how pairs of residues communicate with each other using entropy transfer. The model can identify the residues that drive the fluctuations of others. We apply the model to Ubiquitin, whose allosteric activity has not been emphasized until recently, and show that there are indeed systematic pathways of entropy and information transfer between residues that correlate well with the activities of the protein. We use 600 nanosecond molecular dynamics trajectories for Ubiquitin and its complex with human polymerase iota and evaluate entropy transfer between all pairs of residues of Ubiquitin and quantify the binding susceptibility changes upon complex formation. We explain the complex formation propensities of Ubiquitin in terms of entropy transfer. Important residues taking part in allosteric communication in Ubiquitin predicted by our approach are in agreement with results of NMR relaxation dispersion experiments. Finally, we show that time delayed correlation of fluctuations of two interacting residues possesses an intrinsic causality that tells which residue controls the interaction and which one is controlled. Our work shows that time delayed correlations, entropy transfer and causality are the required new concepts for explaining allosteric communication in proteins.

  1. Influence of Hydration on Proton Transfer in the Guanine-Cytosine Radical Cation (G•+-C) Base Pair: A Density Functional Theory Study

    Science.gov (United States)

    Kumar, Anil; Sevilla, Michael D.

    2009-01-01

    On one-electron oxidation all molecules including DNA bases become more acidic in nature. For the GC base pair experiments suggest that a facile proton transfer takes place in the G•+-C base pair from N1 of G•+ to N3 of cytosine. This intra-base pair proton transfer reaction has been extensively considered using theoretical methods for the gas phase and it is predicted that the proton transfer is slightly unfavorable in disagreement with experiment. In the present study, we consider the effect of the first hydration layer on the proton transfer reaction in G•+-C by the use of density functional theory (DFT), B3LYP/6-31+G** calculations of the G•+-C base pair in the presence of 6 and 11 water molecules. Under the influence of hydration of 11 waters, a facile proton transfer from N1 of G•+ to N3 of C is predicted. The zero point energy (ZPE) corrected forward and backward energy barriers, for the proton transfer from N1 of G•+ to N3 of C, was found to be 1.4 and 2.6 kcal/mol, respectively. The proton transferred G•-(H+)C + 11H2O was found to be 1.2 kcal/mol more stable than G•+-C + 11H2O in agreement with experiment. The present calculation demonstrates that the inclusion of the first hydration shell around G•+-C base pair has an important effect on the internal proton transfer energetics. PMID:19485319

  2. Ultraviolet Absorption Induces Hydrogen-Atom Transfer in G⋅C Watson-Crick DNA Base Pairs in Solution.

    Science.gov (United States)

    Röttger, Katharina; Marroux, Hugo J B; Grubb, Michael P; Coulter, Philip M; Böhnke, Hendrik; Henderson, Alexander S; Galan, M Carmen; Temps, Friedrich; Orr-Ewing, Andrew J; Roberts, Gareth M

    2015-12-01

    Ultrafast deactivation pathways bestow photostability on nucleobases and hence preserve the structural integrity of DNA following absorption of ultraviolet (UV) radiation. One controversial recovery mechanism proposed to account for this photostability involves electron-driven proton transfer (EDPT) in Watson-Crick base pairs. The first direct observation is reported of the EDPT process after UV excitation of individual guanine-cytosine (G⋅C) Watson-Crick base pairs by ultrafast time-resolved UV/visible and mid-infrared spectroscopy. The formation of an intermediate biradical species (G[-H]⋅C[+H]) with a lifetime of 2.9 ps was tracked. The majority of these biradicals return to the original G⋅C Watson-Crick pairs, but up to 10% of the initially excited molecules instead form a stable photoproduct G*⋅C* that has undergone double hydrogen-atom transfer. The observation of these sequential EDPT mechanisms across intermolecular hydrogen bonds confirms an important and long debated pathway for the deactivation of photoexcited base pairs, with possible implications for the UV photochemistry of DNA. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. A Novel Wireless Power Transfer-Based Weighed Clustering Cooperative Spectrum Sensing Method for Cognitive Sensor Networks.

    Science.gov (United States)

    Liu, Xin

    2015-10-30

    In a cognitive sensor network (CSN), the wastage of sensing time and energy is a challenge to cooperative spectrum sensing, when the number of cooperative cognitive nodes (CNs) becomes very large. In this paper, a novel wireless power transfer (WPT)-based weighed clustering cooperative spectrum sensing model is proposed, which divides all the CNs into several clusters, and then selects the most favorable CNs as the cluster heads and allows the common CNs to transfer the received radio frequency (RF) energy of the primary node (PN) to the cluster heads, in order to supply the electrical energy needed for sensing and cooperation. A joint resource optimization is formulated to maximize the spectrum access probability of the CSN, through jointly allocating sensing time and clustering number. According to the resource optimization results, a clustering algorithm is proposed. The simulation results have shown that compared to the traditional model, the cluster heads of the proposed model can achieve more transmission power and there exists optimal sensing time and clustering number to maximize the spectrum access probability.

  4. A Novel Wireless Power Transfer-Based Weighed Clustering Cooperative Spectrum Sensing Method for Cognitive Sensor Networks

    Directory of Open Access Journals (Sweden)

    Xin Liu

    2015-10-01

    Full Text Available In a cognitive sensor network (CSN, the wastage of sensing time and energy is a challenge to cooperative spectrum sensing, when the number of cooperative cognitive nodes (CNs becomes very large. In this paper, a novel wireless power transfer (WPT-based weighed clustering cooperative spectrum sensing model is proposed, which divides all the CNs into several clusters, and then selects the most favorable CNs as the cluster heads and allows the common CNs to transfer the received radio frequency (RF energy of the primary node (PN to the cluster heads, in order to supply the electrical energy needed for sensing and cooperation. A joint resource optimization is formulated to maximize the spectrum access probability of the CSN, through jointly allocating sensing time and clustering number. According to the resource optimization results, a clustering algorithm is proposed. The simulation results have shown that compared to the traditional model, the cluster heads of the proposed model can achieve more transmission power and there exists optimal sensing time and clustering number to maximize the spectrum access probability.

  5. PENGARUH PENGGUNAAN COOPERATIVE LEARNING TIPE THINK-PAIR-SHARE (TPS TERHADAP HASIL BELAJAR KEWIRAUSAHAAN SISWA KELAS X SEMESTER GENAP SMK KARTIKATAMA 1 METRO T.P 2015/2016

    Directory of Open Access Journals (Sweden)

    Safitri Kurnia Lestari

    2016-05-01

    Full Text Available Metode cooperative learning tipe think-pair-share  merupakan model pembelajaran yang melibatkan peserta didik secara maksimal dalam kegiatan pembelajaran mulai dari merencanakan topik-topik yang akan dipelajari, bagaimana mendiskusikan topik suatu materi, hingga melakukan presentasi kelompok dan evaluasi. Adapun yang menjadi masalah dalam penelitian ini yaitu “ Masih banyak peserta didik yang belum tuntas hasil belajar pada mata pelajaran  kewirausahaan  peserta didik kelas X semester genap  SMK Kartikatama 1 Metro  tahun pelajaran 2015/2016”. Adapun tujuan dalam penelitian ini adalah untuk mengetahui pengatuh penggunaan model Cooperative Learning Tipe Think-Pair-Share(TPS terhadap hasil belajar kewirausahaan pada kelas X semester genap SMK Kartikatama 1 metro tahun pelajaran 2015/2016. Maka hipotesis dalam penelitian ini adalah sebagai berikut: “Ada pengaruh positif pengunaan model Cooperative Learning TipeThink-Pair-Share  terhadap hasil belajar  kewirausahaan  peserta didik kelas X semester genap  SMK Kartikatama 1 Metro  tahun pelajaran 2015/2016”. Populasi dalam penelitian ini wilayah yang sebanyak 3 kelas dengan jumlah 71 peserta didik. Sampel dalam penelitian ini adalah kelas X AK 1 yang berjumlah 24sebagai kelas eksperimen dan kelas X AK 2yang berjumlah 21 sebagai kelas kontrol. Setelah dianalisis hasil penelitian dapat disimpulkan bahwa dari analisis perhitungan nilai thitung>ttabel dapat dilihat pada daftar G, pada daftar signifikan 5% yaitu 9,10>1,72. Dan pada taraf signifikan 1% yaitu 9,10>2,51. Dengan demikian hipotesisnya berbunyi bahwa : ada pengaruh positip penggunaan Cooperative Learning Tipe Think-Pair-Share (TPS dapat meningkatkan hasil belajar kewirausahaan siswa kelas X AK 1 semester genap SMK Kartikatama 1 metro tahun pelajaran 2015/2016 pada pokok bahasan mengelola konflik. Siswa yang dinyatakan tuntas dengan KKM (75 setelah treatment sebanyak 14 siswa atau sebesar 58,33% dan siswa yang dinyatakan belum

  6. Ni-Ni ion pair excitation transfer in D sub(3h) symmetry

    International Nuclear Information System (INIS)

    Terrile, M.C.

    1990-01-01

    The mechanisms contributing to excitation transfer are examined for Ni-Ni ion pairs in order to explain the delocalized character of electronic excitations observed in CsNiF sub(3). Using both first-and second-order perturbation theory and from symmetry arguments, the kind of interactions giving matrix elements between states connecting different sites for the position of the excitation are discussed. (author)

  7. Wireless Power Transfer in Cooperative DF Relaying Networks with Log-Normal Fading

    KAUST Repository

    Rabie, Khaled M.; Adebisi, Bamidele; Alouini, Mohamed-Slim

    2017-01-01

    Energy-harvesting (EH) and wireless power transfer in cooperative relaying networks have recently attracted a considerable amount of research attention. Most of the existing work on this topic however focuses on Rayleigh fading channels which represents outdoor environments. Unlike these studies, in this paper we analyze the performance of wireless power transfer in two-hop decode-and- forward (DF) cooperative relaying systems in indoor channels characterized by log-normal fading. Three well-known EH protocols are considered in our evaluations: a) time switching relaying (TSR), b) power splitting relaying (PSR) and c) ideal relaying receiver (IRR). The performance is evaluated in terms of the ergodic outage probability for which we derive accurate analytical expressions for the three systems under consideration. Results reveal that careful selection of the EH time and power splitting factors in the TSR- and PSR-based system are important to optimize performance. It is also presented that the optimized PSR system has near- ideal performance and that increasing the source transmit power and/or the energy harvester efficiency can further improve performance.

  8. Wireless Power Transfer in Cooperative DF Relaying Networks with Log-Normal Fading

    KAUST Repository

    Rabie, Khaled M.

    2017-02-07

    Energy-harvesting (EH) and wireless power transfer in cooperative relaying networks have recently attracted a considerable amount of research attention. Most of the existing work on this topic however focuses on Rayleigh fading channels which represents outdoor environments. Unlike these studies, in this paper we analyze the performance of wireless power transfer in two-hop decode-and- forward (DF) cooperative relaying systems in indoor channels characterized by log-normal fading. Three well-known EH protocols are considered in our evaluations: a) time switching relaying (TSR), b) power splitting relaying (PSR) and c) ideal relaying receiver (IRR). The performance is evaluated in terms of the ergodic outage probability for which we derive accurate analytical expressions for the three systems under consideration. Results reveal that careful selection of the EH time and power splitting factors in the TSR- and PSR-based system are important to optimize performance. It is also presented that the optimized PSR system has near- ideal performance and that increasing the source transmit power and/or the energy harvester efficiency can further improve performance.

  9. Multihop Capability Analysis in Wireless Information and Power Transfer Multirelay Cooperative Networks

    Directory of Open Access Journals (Sweden)

    Qilin Wu

    2018-01-01

    Full Text Available We study simultaneous wireless information and power transfer (SWIPT in multihop wireless cooperative networks, where the multihop capability that denotes the largest number of transmission hops is investigated. By utilizing the broadcast nature of multihop wireless networks, we first propose a cooperative forwarding power (CFP scheme. In CFP scheme, the multiple relays and receiver have distinctly different tasks. Specifically, multiple relays close to the transmitter harvest power from the transmitter first and then cooperatively forward the power (not the information towards the receiver. The receiver receives the information (not the power from the transmitter first, and then it harvests the power from the relays and is taken as the transmitter of the next hop. Furthermore, for performance comparison, we suggest two schemes: cooperative forwarding information and power (CFIP and direct receiving information and power (DFIP. Also, we construct an analysis model to investigate the multihop capabilities of CFP, CFIP, and DFIP schemes under the given targeted throughput requirement. Finally, simulation results validate the analysis model and show that the multihop capability of CFP is better than CFIP and DFIP, and for improving the multihop capabilities, it is best effective to increase the average number of relay nodes in cooperative set.

  10. Bootstrapping Relational Affordances of Object Pairs using Transfer

    DEFF Research Database (Denmark)

    Fichtl, Severin; Kraft, Dirk; Krüger, Norbert

    2018-01-01

    leverage past knowledge to accelerate current learning (which we call bootstrapping). We learn Random Forest based affordance predictors from visual inputs and demonstrate two approaches to knowledge transfer for bootstrapping. In the first approach (direct bootstrapping), the state-space for a new...... affordance predictor is augmented with the output of previously learnt affordances. In the second approach (category based bootstrapping), we form categories that capture underlying commonalities of a pair of existing affordances and augment the state-space with this category classifier’s output. In addition......, we introduce a novel heuristic, which suggests how a large set of potential affordance categories can be pruned to leave only those categories which are most promising for bootstrapping future affordances. Our results show that both bootstrapping approaches outperform learning without bootstrapping...

  11. Nonlinear optical effects and third-harmonic generation in superconductors: Cooper pairs versus Higgs mode contribution

    Science.gov (United States)

    Cea, T.; Castellani, C.; Benfatto, L.

    2016-05-01

    The recent observation of a transmitted THz pulse oscillating at three times the frequency of the incident light paves the way to a powerful protocol to access resonant excitations in a superconductor. Here we show that this nonlinear optical process is dominated by light-induced excitation of Cooper pairs, while the collective amplitude (Higgs) fluctuations of the superconducting order parameter give in general a negligible contribution. We also predict a nontrivial dependence of the signal on the direction of the light polarization with respect to the lattice symmetry, which can be tested in systems such as, e.g., cuprate superconductors.

  12. Foreign cooperative technology development and transfer

    International Nuclear Information System (INIS)

    Schassburger, R.J.; Robinson, R.A.

    1988-01-01

    It is the policy of the US Department of Energy (DOE) that, in pursuing the development of mined geologic repositories in the United States, the waste isolation program will continue to actively support international cooperation and exchange activities that are judged to be in the best interest of the program and in compliance with the Nuclear Waste Policy Act of 1982, Sec. 223. Because there are common technical issues and because technology development often requires large expenditures of funds and dedication of significant capital resources, it is advantageous to cooperate with foreign organizations carrying out similar activities. The DOE's Office of Civilian Radioactive Waste Management is working on cooperative nuclear waste isolation technology development programs with the Organization for Economic Cooperation and Development/Nuclear Energy Agency (OECD/NEA), Canada's Atomic Energy of Canada, Limited (AECL), Sweden, Switzerland, and the Federal Republic of Germany. This paper describes recent technology results that have been obtained in DOE's foreign cooperative programs. Specific technology development studies are discussed for cooperative efforts with Canada, OECD/NEA, and a natural analog project in Brazil

  13. Skew Information for a Single Cooper Pair Box Interacting with a Single Cavity Field

    International Nuclear Information System (INIS)

    Metwally, N.; Al-Mannai, A.; Abdel-Aty, M.

    2013-01-01

    The dynamics of the skew information (SI) is investigated for a single Cooper Pair Box (CPB) interacting with a single cavity field. By suitably choosing the system parameters and precisely controlling the dynamics, novel connection is found between the SI and entanglement generation. It is shown that SI can be increased and reach its maximum value either by increasing the number of photons inside the cavity or considering the far off-resonant case. The number of oscillations of SI is increased by decreasing this ratio between the Josephson junction capacity and the gate capacity. This leads to significant improvement of the travelling time between the maximum and minimum values. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  14. Theory of superconductivity with non-Hermitian and parity-time reversal symmetric Cooper pairing symmetry

    Science.gov (United States)

    Ghatak, Ananya; Das, Tanmoy

    2018-01-01

    Recently developed parity (P ) and time-reversal (T ) symmetric non-Hermitian systems govern a rich variety of new and characteristically distinct physical properties, which may or may not have a direct analog in their Hermitian counterparts. We study here a non-Hermitian, PT -symmetric superconducting Hamiltonian that possesses a real quasiparticle spectrum in the PT -unbroken region of the Brillouin zone. Within a single-band mean-field theory, we find that real quasiparticle energies are possible when the superconducting order parameter itself is either Hermitian or anti-Hermitian. Within the corresponding Bardeen-Cooper-Schrieffer (BCS) theory, we find that several properties are characteristically distinct and novel in the non-Hermitian pairing case than its Hermitian counterpart. One of our significant findings is that while a Hermitian superconductor gives a second-order phase transition, the non-Hermitian one produces a robust first-order phase transition. The corresponding thermodynamic properties and the Meissner effect are also modified accordingly. Finally, we discuss how such a PT -symmetric pairing can emerge from an antisymmetric potential, such as the Dzyloshinskii-Moriya interaction, but with an external bath, or complex potential, among others.

  15. Evidence for pair correlation effects in heavy ion reactions

    CERN Document Server

    Auditore, L; D'Amico, V; De Pasquale, D; Trifiró, A; Trimarchi, M; Italiano, A

    2003-01-01

    The study of the sup 1 sup 2 C( sup 1 sup 4 N, sup 1 sup 4 N) sup 1 sup 2 C reaction was performed at 28 and 35 MeV beam energies. The results were analyzed in the frame of the EFRDWBA (Exact-Finite-Range Distorted Wave Born Approximation) assuming the simultaneous and sequential transfer of a np pair. The angular distributions, fairly reproduced in the first case, confirm the validity of the generalized BCS (Bardeen-Cooper-Schrieffer) theory to explain this behaviour. Moreover, this process could be regarded as a possible Nuclear Josephson Effect. (author)

  16. Simultaneous Wireless Power Transfer and Secure Multicasting in Cooperative Decode-and-Forward Relay Networks.

    Science.gov (United States)

    Lee, Jong-Ho; Sohn, Illsoo; Kim, Yong-Hwa

    2017-05-16

    In this paper, we investigate simultaneous wireless power transfer and secure multicasting via cooperative decode-and-forward (DF) relays in the presence of multiple energy receivers and eavesdroppers. Two scenarios are considered under a total power budget: maximizing the minimum harvested energy among the energy receivers under a multicast secrecy rate constraint; and maximizing the multicast secrecy rate under a minimum harvested energy constraint. For both scenarios, we solve the transmit power allocation and relay beamformer design problems by using semidefinite relaxation and bisection technique. We present numerical results to analyze the energy harvesting and secure multicasting performances in cooperative DF relay networks.

  17. PENGARUH PELAKSANAAN MODEL PEMBELAJARAN KOOPERATIF TIPE THINK PAIR SHARE TERHADAP HASIL BELAJAR IPS SISWA

    Directory of Open Access Journals (Sweden)

    andi fathur asdar

    2016-08-01

    Full Text Available The objective of this research was to describe: 1 Teacher ability in the implementation of cooperative learning Think Pair Share, 2 Ttudent activities in the implementation of cooperative learning Think Pair Share, 3 Tearning result on IPS before and after the implementation of cooperative learning Think Pair Share, 4 learning result on IPS before and after learning process with lecture method, 5 to find out the influence of the implementation of cooperative learning Think Pair Share toward learning result on IPS. The method used was true experiment with pre-test post-test control group design. The population in the study are 4th grade student at SDN Sungguminasa II Somba Opu District Gowa Regency. Samples used are 40 student 20 student each from experiment and comparing group. chosen by simple random sampling. The data obtained from samples were analyzed with descritive and inferensial statistic. The result shows: 1 teacher ability in the implementation of cooperative learning Think Pair Share have increased, 2 student activities in the implementation of cooperative learning Think Pair Share, 3 student learning result who teached by cooperative learning Think Pair Share have increased, 4 student learning result who teached by lecture method have not increased, 5 the implementation of cooperative learning Think Pair Share is influencing toward learning result on IPS in 4th grade student at SDN Sungguminasa II Somba Opu District Gowa Regency.

  18. Influence of isovector pairing and particle-number projection effects on spectroscopic factors for one-pair like-particle transfer reactions in proton-rich even-even nuclei

    Science.gov (United States)

    Benbouzid, Y.; Allal, N. H.; Fellah, M.; Oudih, M. R.

    2018-04-01

    Isovector neutron-proton (np) pairing and particle-number fluctuation effects on the spectroscopic factors (SF) corresponding to one-pair like-particle transfer reactions in proton-rich even-even nuclei are studied. With this aim, expressions of the SF corresponding to two-neutron stripping and two-proton pick-up reactions, which take into account the isovector np pairing effect, are established within the generalized BCS approach, using a schematic definition proposed by Chasman. Expressions of the same SF which strictly conserve the particle number are also established within the Sharp-BCS (SBCS) discrete projection method. In both cases, it is shown that these expressions generalize those obtained when only the pairing between like particles is considered. First, the formalism is tested within the Richardson schematic model. Second, it is applied to study even-even proton-rich nuclei using the single-particle energies of a Woods-Saxon mean-field. In both cases, it is shown that the np pairing effect and the particle-number projection effect on the SF values are important, particularly in N = Z nuclei, and must then be taken into account.

  19. Simultaneous Wireless Power Transfer and Secure Multicasting in Cooperative Decode-and-Forward Relay Networks

    Science.gov (United States)

    Lee, Jong-Ho; Sohn, Illsoo; Kim, Yong-Hwa

    2017-01-01

    In this paper, we investigate simultaneous wireless power transfer and secure multicasting via cooperative decode-and-forward (DF) relays in the presence of multiple energy receivers and eavesdroppers. Two scenarios are considered under a total power budget: maximizing the minimum harvested energy among the energy receivers under a multicast secrecy rate constraint; and maximizing the multicast secrecy rate under a minimum harvested energy constraint. For both scenarios, we solve the transmit power allocation and relay beamformer design problems by using semidefinite relaxation and bisection technique. We present numerical results to analyze the energy harvesting and secure multicasting performances in cooperative DF relay networks. PMID:28509841

  20. Simultaneous Wireless Power Transfer and Secure Multicasting in Cooperative Decode-and-Forward Relay Networks

    Directory of Open Access Journals (Sweden)

    Jong-Ho Lee

    2017-05-01

    Full Text Available In this paper, we investigate simultaneous wireless power transfer and secure multicasting via cooperative decode-and-forward (DF relays in the presence of multiple energy receivers and eavesdroppers. Two scenarios are considered under a total power budget: maximizing the minimum harvested energy among the energy receivers under a multicast secrecy rate constraint; and maximizing the multicast secrecy rate under a minimum harvested energy constraint. For both scenarios, we solve the transmit power allocation and relay beamformer design problems by using semidefinite relaxation and bisection technique. We present numerical results to analyze the energy harvesting and secure multicasting performances in cooperative DF relay networks.

  1. Positive Noise Cross Correlation in a Copper Pair Splitter.

    Science.gov (United States)

    Das, Anindya; Ronen, Yuval; Heiblum, Moty; Shtrikman, Hadas; Mahalu, Diana

    2012-02-01

    Entanglement is in heart of the Einstein-Podolsky-Rosen (EPR) paradox, in which non-locality is a fundamental property. Up to date spin entanglement of electrons had not been demonstrated. Here, we provide direct evidence of such entanglement by measuring: non-local positive current correlation and positive cross correlation among current fluctuations, both of separated electrons born by a Cooper-pair-beam-splitter. The realization of the splitter is provided by injecting current from an Al superconductor contact into two, single channel, pure InAs nanowires - each intercepted by a Coulomb blockaded quantum dot (QD). The QDs impedes strongly the flow of Cooper pairs allowing easy single electron transport. The passage of electron in one wire enables the simultaneous passage of the other in the neighboring wire. The splitting efficiency of the Cooper pairs (relative to Cooper pairs actual current) was found to be ˜ 40%. The positive cross-correlations in the currents and their fluctuations (shot noise) are fully consistent with entangled electrons produced by the beam splitter.

  2. Exotic Paired States with Anisotropic Spin-Dependent Fermi Surfaces

    International Nuclear Information System (INIS)

    Feiguin, Adrian E.; Fisher, Matthew P. A.

    2009-01-01

    We propose a model for realizing exotic paired states in cold Fermi gases by using a spin-dependent optical lattice to engineer mismatched Fermi surfaces for each hyperfine species. The BCS phase diagram shows a stable paired superfluid state with coexisting pockets of momentum space with gapless unpaired carriers, similar to the Sarma state in polarized mixtures, but in our case the system is unpolarized. We propose the possible existence of an exotic 'Cooper-pair Bose-metal' phase, which has a gap for single fermion excitations but gapless and uncondensed 'Cooper-pair' excitations residing on a 'Bose surface' in momentum space.

  3. Blinking fluorescence of single donor-acceptor pairs: important role of "dark'' states in resonance energy transfer via singlet levels.

    Science.gov (United States)

    Osad'ko, I S; Shchukina, A L

    2012-06-01

    The influence of triplet levels on Förster resonance energy transfer via singlet levels in donor-acceptor (D-A) pairs is studied. Four types of D-A pair are considered: (i) two-level donor and two-level acceptor, (ii) three-level donor and two-level acceptor, (iii) two-level donor and three-level acceptor, and (iv) three-level donor and three-level acceptor. If singlet-triplet transitions in a three-level acceptor molecule are ineffective, the energy transfer efficiency E=I_{A}/(I_{A}+I_{D}), where I_{D} and I_{A} are the average intensities of donor and acceptor fluorescence, can be described by the simple theoretical equation E(F)=FT_{D}/(1+FT_{D}). Here F is the rate of energy transfer, and T_{D} is the donor fluorescence lifetime. In accordance with the last equation, 100% of the donor electronic energy can be transferred to an acceptor molecule at FT_{D}≫1. However, if singlet-triplet transitions in a three-level acceptor molecule are effective, the energy transfer efficiency is described by another theoretical equation, E(F)=F[over ¯](F)T_{D}/[1+F[over ¯](F)T_{D}]. Here F[over ¯](F) is a function of F depending on singlet-triplet transitions in both donor and acceptor molecules. Expressions for the functions F[over ¯](F) are derived. In this case the energy transfer efficiency will be far from 100% even at FT_{D}≫1. The character of the intensity fluctuations of donor and acceptor fluorescence indicates which of the two equations for E(F) should be used to find the value of the rate F. Therefore, random time instants of photon emission in both donor and acceptor fluorescence are calculated by the Monte Carlo method for all four types of D-A pair. Theoretical expressions for start-stop correlators (waiting time distributions) in donor and acceptor fluorescence are derived. The probabilities w_{N}^{D}(t) and w_{N}^{A}(t) of finding N photons of donor and acceptor fluorescence in the time interval t are calculated for various values of the energy

  4. MODEL PEMBELAJARAN KOOPERATIF TIPE THINK PAIR SHARE DAN HASIL BELAJAR DI SEKOLAH

    Directory of Open Access Journals (Sweden)

    Elhefni Elhefni

    2011-11-01

    Full Text Available Abstract Cooperative learning is learning that requires students to be responsible for himself and his group are responsible for. With cooperative learning students will more easily find and understand difficult concepts if they were in discussions with his students regularly work in groups to help each other in solving complex problems. In cooperative learning are learning techniques of the type of think-pair-share. Type of cooperative learning model think-pair-share it has the advantage that students can be a lot of time to think, respond, and help each other, the teacher only to deliver the material briefly, then ask a question, then the teacher wants students to think more deeply about the material that has been described and experienced. This technique can encourage students to enthusiastic in working together, and by applying a type of cooperative learning model think-pair-share is expected to better learning outcomes for students who learn on their own. Keywords: Type of cooperative learning model think-pair-share, learning outcomes

  5. Spectral density of Cooper pairs in two level quantum dot–superconductors Josephson junction

    Energy Technology Data Exchange (ETDEWEB)

    Dhyani, A., E-mail: archana.d2003@gmail.com [Department of Physics, University of Petroleum and Energy Studies, Dehradun 248007, Uttarakhand (India); Rawat, P.S. [Department of Nuclear Science and Technology, University of Petroleum and Energy Studies, Dehradun 248007, Uttarakhand (India); Tewari, B.S., E-mail: bstewari@ddn.upes.ac.in [Department of Physics, University of Petroleum and Energy Studies, Dehradun 248007, Uttarakhand (India)

    2016-09-15

    Highlights: • The present work deals with the study of the electronic spectral density of electron pairs and its effect in charge transport in superconductor-quantum dot-superconductor junctions. • The charge transfer across such junctions can be controlled by changing the positions of the dot level. • The Josephson supercurrent can also be tuned by controlling the position of quantum dot energy levels. - Abstract: In the present paper, we report the role of quantum dot energy levels on the electronic spectral density for a two level quantum dot coupled to s-wave superconducting leads. The theoretical arguments in this work are based on the Anderson model so that it necessarily includes dot energies, single particle tunneling and superconducting order parameter for BCS superconductors. The expression for single particle spectral function is obtained by using the Green's function equation of motion technique. On the basis of numerical computation of spectral function of superconducting leads, it has been found that the charge transfer across such junctions can be controlled by the positions and availability of the dot levels.

  6. On magnon mediated Cooper pair formation in ferromagnetic superconductors

    Directory of Open Access Journals (Sweden)

    Rakesh Kar

    2014-08-01

    Full Text Available Identification of pairing mechanism leading to ferromagnetic superconductivity is one of the most challenging issues in condensed matter physics. Although different models have been proposed to explain this phenomenon, a quantitative understanding about this pairing is yet to be achieved. Using the localized-itinerant model, we find that in ferromagnetic superconducting materials both triplet pairing and singlet pairing of electrons are possible through magnon exchange depending upon whether the Debye cut off frequency of magnons is greater or lesser than the Hund's coupling (J multiplied by average spin (S per site. Taking into account the repulsive interaction due to the existence of paramagnons, we also find an expression for effective interaction potential between a pair of electrons with opposite spins. We apply the developed formalism in case of UGe2 and URhGe. The condition of singlet pairing is found to be fulfilled in these cases, as was previously envisaged by Suhl [Suhl, Phys. Rev. Lett. 87, 167007 (2001]. We compute the critical temperatures of URhGe at ambient pressure and of UGe2 under different pressures for the first time through BCS equation. Thus, this work outlines a very simple way to evaluate critical temperature in case of a superconducting system. A close match with the available experimental results strongly supports our theoretical treatment.

  7. Pairing correlations in nuclei

    International Nuclear Information System (INIS)

    Baba, C.V.K.

    1988-01-01

    There are many similarities between the properties of nucleons in nuclei and electrons in metals. In addition to the properties explainable in terms of independent particle motion, there are many important co-operative effects suggesting correlated motion. Pairing correlation which leads to superconductivity in metals and several important properties in nuclei , is an exmple of such correlations. An attempt has been made to review the effects of pairing correlations in nuclei. Recent indications of reduction in pairing correlations at high angular momenta is discussed. A comparision between pairing correlations in the cases of nuclei and electrons in metals is attempted. (author). 20 refs., 10 figs

  8. Knowledge transfer and innovation in cross-border cooperation programmes between Finland and Russia

    DEFF Research Database (Denmark)

    Makkonen, Teemu; Williams, Allan; Weidenfeld, Adi

    2017-01-01

    Cross-border cooperation (CBC) at the European Union’s (EU) external borders has been promoted via programmes, such as the European Neighbourhood and Partnership Instrument (ENPI), funded jointly by the EU and participating countries. However, little empirical attention has been laid to these pro...... the actors in opposing sides of the border, is actually the main factor that facilitates and creates potential for learning, knowledge transfer and innovation to take place in the Finnish-Russian cross-border region....... to these programmes in terms of their role in enhancing cross-border knowledge transfer and innovation, particularly in the field of tourism. To shed light on the issue, semi-structured interviews were conducted with representatives of (12 Russian; 12 Finnish) organisations that had participated in ENPI CBC funded...... tourism related Finnish-Russian cross-border projects. The results shed light on the possibilities of and obstacles to cross-border knowledge transfer and innovation. ENPI CBC programmes between Finland and Russia are highly relevant for successful cross-border knowledge transfer and innovation...

  9. A new pathway for transmembrane electron transfer in photosynthetic reaction centers of Rhodobacter sphaeroides not involving the excited special pair.

    NARCIS (Netherlands)

    van Brederode, M.E.; Jones, M.R.; van Mourik, F.; van Stokkum, I.H.M.; van Grondelle, R.

    1997-01-01

    It is generally accepted that electron transfer in bacterial photosynthesis is driven by the first singlet excited state of a special pair of bacteriochlorophylls (P*). We have examined the first steps of electron transfer in a mutant of the Rhodobacter sphaeroides reaction center in which charge

  10. A new pathway for transmembrane electron transfer in photosyntetic reaction centers of Rhodobacter sphaeroides not involving the excited special pair.

    NARCIS (Netherlands)

    van Brederode, M.E.; Jones, M.R.; van Mourik, F.; van Stokkum, I.H.M.; van Grondelle, R.

    1997-01-01

    It is generally accepted that electron transfer in bacterial photosynthesis is driven by the first singlet excited state of a special pair of bacteriochlorophylls (P*). We have examined the first steps of electron transfer in a mutant of the Rhodobacter sphaeroides reaction center in which charge

  11. Extra-pair parentage and personality in a cooperatively breeding bird

    NARCIS (Netherlands)

    Edwards, Hannah A; Dugdale, Hannah L; Richardson, David S; Komdeur, Jan; Burke, Terry

    Abstract: Why so much variation in extra-pair parentage occurs within and among populations remains unclear. Often the fitness costs and benefits of extra-pair parentage are hypothesised to explain its occurrence; therefore, linking extra-pair parentage with traits such as personality (behavioural

  12. Dual origin of pairing in nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Idini, A. [University of Jyvaskyla, Department of Physics (Finland); Potel, G. [Michigan State University, National Superconducting Cyclotron Laboratory (United States); Barranco, F. [Escuela Superior de Ingenieros, Universidad de Sevilla, Departamento de Fìsica Aplicada III (Spain); Vigezzi, E., E-mail: enrico.vigezzi@mi.infn.it [INFN Sezione di Milano (Italy); Broglia, R. A. [Università di Milano, Dipartimento di Fisica (Italy)

    2016-11-15

    The pairing correlations of the nucleus {sup 120}Sn are calculated by solving the Nambu–Gor’kov equations, including medium polarization effects resulting from the interweaving of quasiparticles, spin and density vibrations, taking into account, within the framework of nuclear field theory (NFT), processes leading to self-energy and vertex corrections and to the induced pairing interaction. From these results one can not only demonstrate the inevitability of the dual origin of pairing in nuclei, but also extract information which can be used at profit to quantitatively disentangle the contributions to the pairing gap Δ arising from the bare and from the induced pairing interaction. The first is the strong {sup 1}S{sub 0} short-range NN potential resulting from meson exchange between nucleons moving in time reversal states within an energy range of hundreds of MeV from the Fermi energy. The second results from the exchange of vibrational modes between nucleons moving within few MeV from the Fermi energy. Short- (v{sub p}{sup bare}) and long-range (v{sub p}{sup ind}) pairing interactions contribute essentially equally to nuclear Cooper pair stability. That is to the breaking of gauge invariance in open-shell superfluid nuclei and thus to the order parameter, namely to the ground state expectation value of the pair creation operator. In other words, to the emergent property of generalized rigidity in gauge space, and associated rotational bands and Cooper pair tunneling between members of these bands.

  13. Dual origin of pairing in nuclei

    Science.gov (United States)

    Idini, A.; Potel, G.; Barranco, F.; Vigezzi, E.; Broglia, R. A.

    2016-11-01

    The pairing correlations of the nucleus 120Sn are calculated by solving the Nambu-Gor'kov equations, including medium polarization effects resulting from the interweaving of quasiparticles, spin and density vibrations, taking into account, within the framework of nuclear field theory (NFT), processes leading to self-energy and vertex corrections and to the induced pairing interaction. From these results one can not only demonstrate the inevitability of the dual origin of pairing in nuclei, but also extract information which can be used at profit to quantitatively disentangle the contributions to the pairing gap Δ arising from the bare and from the induced pairing interaction. The first is the strong 1 S 0 short-range NN potential resulting from meson exchange between nucleons moving in time reversal states within an energy range of hundreds of MeV from the Fermi energy. The second results from the exchange of vibrational modes between nucleons moving within few MeV from the Fermi energy. Short- ( v p bare) and long-range ( v p ind) pairing interactions contribute essentially equally to nuclear Cooper pair stability. That is to the breaking of gauge invariance in open-shell superfluid nuclei and thus to the order parameter, namely to the ground state expectation value of the pair creation operator. In other words, to the emergent property of generalized rigidity in gauge space, and associated rotational bands and Cooper pair tunneling between members of these bands.

  14. Possible evidence for spin-transfer torque induced by spin-triplet supercurrent

    KAUST Repository

    Li, Lailai; Zhao, Yuelei; Zhang, Xixiang; Sun, Young

    2017-01-01

    Cooper pairs in superconductors are normally spin singlet. Nevertheless, recent studies suggest that spin-triplet Cooper pairs can be created at carefully engineered superconductor-ferromagnet interfaces. If Cooper pairs are spin

  15. Technological transfers and cooperation in the field of climatic change

    International Nuclear Information System (INIS)

    Riedacker, A.

    2002-01-01

    Fighting against climatic changes and adapting to them is a necessary condition to achieve sustainable development. The ultimate goal of the Framework Convention on Climate Change signed in Rio in 1992, and specified in article 2, is to stabilize the concentrations of greenhouse gases at a level that does not threaten climatic systems and allows ecosystems to adapt to climatic change, ensures that food production is not in danger and that sustainable development be achieved. A radical paradigm change is required, and in particular the adoption of new technologies. First, the new technologies must assist in limiting the emissions of greenhouse gases, both in industrialized and developing countries, and to adapt to the climatic changes. The author is of the opinion that technology transfers represent a means to address the issue of climatic change. The concentration of carbon dioxide in the atmosphere continues to increase since the advent of the industrial revolution. It seems dubious that we will be able to stabilize the climate to its actual level, therefore we must learn to adapt while continuing to reduce the emissions of greenhouse gases. The author then examines the technological cooperation since the adoption of the Marrakech Accords in 2001. The next section deals with technological cooperation between francophone cities of the north and francophone cities of the south. The author concludes by placing the emphasis on the importance of regular meetings and the implementation of specialized networks, such as the network on the technology of arid regions, in an effort to assist the technological cooperation north-south and south-south in the fight against climatic change. 2 figs

  16. Heteroditopic receptors for ion-pair recognition.

    Science.gov (United States)

    McConnell, Anna J; Beer, Paul D

    2012-05-21

    Ion-pair recognition is a new field of research emerging from cation and anion coordination chemistry. Specific types of heteroditopic receptor designs for ion pairs and the complexity of ion-pair binding are discussed to illustrate key concepts such as cooperativity. The importance of this area of research is reflected by the wide variety of potential applications of ion-pair receptors, including applications as membrane transport and salt solubilization agents and sensors. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Making Cooperative Learning Groups Work.

    Science.gov (United States)

    Hawley, James; De Jong, Cherie

    1995-01-01

    Discusses the use of cooperative-learning groups with middle school students. Describes cooperative-learning techniques, including group roles, peer evaluation, and observation and monitoring. Considers grouping options, including group size and configuration, dyads, the think-pair-share lecture, student teams achievement divisions, jigsaw groups,…

  18. Mesoscopic pairing without superconductivity

    Science.gov (United States)

    Hofmann, Johannes

    2017-12-01

    We discuss pairing signatures in mesoscopic nanowires with a variable attractive pairing interaction. Depending on the wire length, density, and interaction strength, these systems realize a simultaneous bulk-to-mesoscopic and BCS-BEC crossover, which we describe in terms of the parity parameter that quantifies the odd-even energy difference and generalizes the bulk Cooper pair binding energy to mesoscopic systems. We show that the parity parameter can be extracted from recent measurements of conductance oscillations in SrTiO3 nanowires by Cheng et al. [Nature (London) 521, 196 (2015), 10.1038/nature14398], where it marks the critical magnetic field that separates pair and single-particle currents. Our results place the experiment in the fluctuation-dominated mesoscopic regime on the BCS side of the crossover.

  19. Spin correlation and entanglement detection in Cooper pair splitters by current measurements using magnetic detectors

    Science.gov (United States)

    Busz, Piotr; Tomaszewski, Damian; Martinek, Jan

    2017-08-01

    We analyze a model of a double quantum dot Cooper pair splitter coupled to two ferromagnetic detectors and demonstrate the possibility of determination of spin correlation by current measurements. We use perturbation theory, taking account of the exchange interaction with the detectors, which leads to complex spin dynamics in the dots. This affects the measured spin and restricts the use of ferromagnetic detectors to the nonlinear current-voltage characteristic regime at the current plateau, where the relevant spin projection is conserved, in contrast to the linear current-voltage characteristic regime, in which the spin information is distorted. Moreover, we show that for separable states the spin correlation can only be determined in a limited parameter regime, much more restricted than in the case of entangled states. We propose an entanglement test based on the Bell inequality.

  20. Bilateral cooperation and technology transfer between France and China at Daya-Bay, Qinshan II and Yibin

    International Nuclear Information System (INIS)

    Ma Fubanf; Zenf Wenxing; He Jiacheng; Charbonneau, S.; Darolles, J.F.; Ellia, G.; Freslon, H.

    1994-01-01

    The Daya-Bay nuclear power station in Guangdong Province, The Qinshan phase II nuclear power station in Zhejiang Province, and the fuel manufacturing facility at Yibin in Sichuan Province have all afforded Framatome the opportunity to develop wide-ranging bilateral cooperation and technology transfer with the People's Republic of china. These projects are all good examples of how a country with some nuclear power experience, such as the now-operating Qinshan 1 (300 M We) nuclear power unit designed and build by China itself, can make much more rapid progress in its civil nuclear power program through cooperation with an industry leader, such as Framatome

  1. A Subcarrier-Pair Based Resource Allocation Scheme Using Proportional Fairness for Cooperative OFDM-Based Cognitive Radio Networks

    Science.gov (United States)

    Ma, Yongtao; Zhou, Liuji; Liu, Kaihua

    2013-01-01

    The paper presents a joint subcarrier-pair based resource allocation algorithm in order to improve the efficiency and fairness of cooperative multiuser orthogonal frequency division multiplexing (MU-OFDM) cognitive radio (CR) systems. A communication model where one source node communicates with one destination node assisted by one half-duplex decode-and-forward (DF) relay is considered in the paper. An interference-limited environment is considered, with the constraint of transmitted sum-power over all channels and aggregate average interference towards multiple primary users (PUs). The proposed resource allocation algorithm is capable of maximizing both the system transmission efficiency and fairness among secondary users (SUs). Besides, the proposed algorithm can also keep the interference introduced to the PU bands below a threshold. A proportional fairness constraint is used to assure that each SU can achieve a required data rate, with quality of service guarantees. Moreover, we extend the analysis to the scenario where each cooperative SU has no channel state information (CSI) about non-adjacent links. We analyzed the throughput and fairness tradeoff in CR system. A detailed analysis of the performance of the proposed algorithm is presented with the simulation results. PMID:23939586

  2. Pseudogap from preformed Cooper pairs in a platinum-iron-arsenide superconductor

    Energy Technology Data Exchange (ETDEWEB)

    Surmach, M.A.; Brueckner, F.; Kamusella, S.; Sarkar, R.; Portnichenko, P.Y.; Klauss, H.H.; Inosov, D.S. [TU Dresden (Germany); Park, J.T. [MLZ, Garching (Germany); Luetkens, H.; Biswas, P. [PSI, Villigen (Switzerland); Choi, W.J.; Seo, Y.I.; Kwon, Y.S. [DGIST, Daegu (Korea, Republic of)

    2015-07-01

    Using a combination of μSR, INS and NMR, we investigated the novel iron-based superconductor with a triclinic crystal structure (CaFe{sub 1-x}Pt{sub x}As){sub 10}Pt{sub 3}As{sub 8} (T{sub c}=13 K). The T-dependence of the superfluid density from our μSR relaxation-rate measurements indicates the presence of two superconducting gaps. According to our INS measurements, commensurate spin fluctuations are centered at the (π, 0) wave vector. Their intensity is unchanged across T{sub c}, indicating the absence of a spin resonance typical for many Fe-based superconductors. Instead, we observed a peak in the spin-excitation spectrum around ℎω{sub 0}=7 meV at the same wave vector, which persists above T{sub c}. The temperature dependence of magnetic intensity at 7 meV revealed an anomaly around T*=45 K related to the disappearance of this new mode. A suppression of the spin-lattice relaxation rate, 1/T{sub 1}T, observed by NMR immediately below T* without any notable subsequent anomaly at T{sub c}, indicates that T* could mark the onset of a pseudogap in (CaFe{sub 1-x}Pt{sub x}As){sub 10}Pt{sub 3}As{sub 8}, which is likely associated with the emergence of preformed Cooper pairs.

  3. A Novel k-out-of-n Oblivious Transfer Protocol from Bilinear Pairing

    Directory of Open Access Journals (Sweden)

    Jue-Sam Chou

    2012-01-01

    Full Text Available Oblivious transfer (OT protocols mainly contain three categories: 1-out-of-2 OT, 1-out-of-n OT, and k-out-of-n OT. In most cases, they are treated as cryptographic primitives and are usually executed without consideration of possible attacks that might frequently occur in an open network, such as an impersonation, replaying, or man-in-the-middle attack. Therefore, when used in certain applications, such as mental poker games and fair contract signings, some extra mechanisms must be combined to ensure the security of the protocol. However, after a combination, we found that very few of the resulting schemes are efficient enough in terms of communicational cost, which is a significant concern for generic commercial transactions. Therefore, we propose a novel k-out-of-n oblivious transfer protocol based on bilinear pairing, which not only satisfies the requirements of a k-out-of-n OT protocol, but also provides mutual authentication to resist malicious attacks. Meanwhile, it is efficient in terms of communication cost.

  4. Cooper pairs versus Bose condensed molecules: The ground-state current in superfluid 3He-A

    International Nuclear Information System (INIS)

    Mermin, N.D.; Muzikar, P.

    1980-01-01

    We present a new calculation of the current g flowing in a ground state of the Bardeen-Cooper-Schrieffer (BCS) form for a weakly inhomogeneous superfluid with the symmetry of 3 He-A. When the structure of the order parameter not determined by symmetry is appropriate to 3 He-A and when the mass density rho of the helium is essentially uniform, our current reduces to that calculated by Cross. If the mass density is allowed to vary, we find a generalization of the Cross current which shows that when v/sub s/=0 and the anisotropy axis l is uniform, then the current is simply (h/4M) del-arrow-rightrho x l. We show that this property of the BCS ground state, which taken with the Cross definition leads to an ''intrinsic angular momentum density'' of rhoh/2M at zero temperature, also follows directly from the Gor'kov equations. If the range of the order parameter is taken to be small compared with the interatomic separation, then the ground state does not describe 3 He-A, but a Bose-Einstein condensate of tightly bound diatomic molecules. In this limit our current reduces to the form calculated by Ishikawa et al. We indicate why their analysis is only valid in this limit, and offer some rather more general remarks on the differences between Cooper pairing and the Bose-Einstein condensation of diatomic molecules

  5. Students' Perceptions of Cooperative Learning Strategies in Post-Secondary Classrooms.

    Science.gov (United States)

    Fennell, Hope-Arlene

    A study of graduate students in education and forestry explored their preferences and perceptions of cooperative learning strategies. The study examined strategies derived from the work of R. Slavin and D. Johnson including the following: think-pair-square, think-pair-share, jigsaw strategies, and cooperative group investigation. Of the 208…

  6. Neutron pair and proton pair transfer reactions between identical cores in the sulfur region

    International Nuclear Information System (INIS)

    Mermaz, M.C.

    1995-12-01

    Optical model and exact finite range distorted-wave Born approximation analyses were performed on neutron pair exchange between identical cores for 32 S and 34 S nuclei and on proton pair exchange between identical cores for 30 Si and 32 S. The extracted spectroscopic factors were compared with theoretical ones deduced from Hartree-Fock calculations on these pair of nuclei. The enhancement of the experimental cross sections with respect to the theoretical ones strongly suggests evidence for a nuclear Josephson effect. (author). 15 refs., 5 figs., 3 tabs

  7. The behavior of exciplex decay processes and interplay of radiationless transition and preliminary reorganization mechanisms of electron transfer in loose and tight pairs of reactants.

    Science.gov (United States)

    Kuzmin, Michael G; Soboleva, Irina V; Dolotova, Elena V

    2007-01-18

    Exciplex emission spectra and rate constants of their decay via internal conversion and intersystem crossing are studied and discussed in terms of conventional radiationless transition approach. Exciplexes of 9-cyanophenanthrene with 1,2,3-trimethoxybenzene and 1,3,5-trimethoxybenzene were studied in heptane, toluene, butyl acetate, dichloromethane, butyronitrile, and acetonitrile. A better description of spectra and rate constants is obtained using 0-0 transition energy and Gauss broadening of vibrational bands rather than the free energy of electron transfer and reorganization energy. The coincidence of parameters describing exciplex emission spectra and dependence of exciplex decay rate constants on energy gap gives the evidence of radiationless quantum transition mechanism rather than thermally activated medium reorganization mechanism of charge recombination in exciplexes and excited charge transfer complexes (contact radical ion pairs) as well as in solvent separated radical ion pairs. Radiationless quantum transition mechanism is shown to provide an appropriate description also for the main features of exergonic excited-state charge separation reactions if fast mutual transformations of loose and tight pairs of reactants are considered. In particular, very fast electron transfer (ET) in tight pairs of reactants with strong electronic coupling of locally excited and charge transfer states can prevent the observation of an inverted region in bimolecular excited-state charge separation even for highly exergonic reactions.

  8. Pairing States of Spin-3/2 Fermions: Symmetry-Enforced Topological Gap Functions

    Science.gov (United States)

    Venderbos, Jörn W. F.; Savary, Lucile; Ruhman, Jonathan; Lee, Patrick A.; Fu, Liang

    2018-01-01

    We study the topological properties of superconductors with paired j =3/2 quasiparticles. Higher spin Fermi surfaces can arise, for instance, in strongly spin-orbit coupled band-inverted semimetals. Examples include the Bi-based half-Heusler materials, which have recently been established as low-temperature and low-carrier density superconductors. Motivated by this experimental observation, we obtain a comprehensive symmetry-based classification of topological pairing states in systems with higher angular momentum Cooper pairing. Our study consists of two main parts. First, we develop the phenomenological theory of multicomponent (i.e., higher angular momentum) pairing by classifying the stationary points of the free energy within a Ginzburg-Landau framework. Based on the symmetry classification of stationary pairing states, we then derive the symmetry-imposed constraints on their gap structures. We find that, depending on the symmetry quantum numbers of the Cooper pairs, different types of topological pairing states can occur: fully gapped topological superconductors in class DIII, Dirac superconductors, and superconductors hosting Majorana fermions. Notably, we find a series of nematic fully gapped topological superconductors, as well as double- and triple-Dirac superconductors, with quadratic and cubic dispersion, respectively. Our approach, applied here to the case of j =3/2 Cooper pairing, is rooted in the symmetry properties of pairing states, and can therefore also be applied to other systems with higher angular momentum and high-spin pairing. We conclude by relating our results to experimentally accessible signatures in thermodynamic and dynamic probes.

  9. DNA base pair resolution measurements using resonance energy transfer efficiency in lanthanide doped nanoparticles.

    Directory of Open Access Journals (Sweden)

    Aleksandra Delplanque

    Full Text Available Lanthanide-doped nanoparticles are of considerable interest for biodetection and bioimaging techniques thanks to their unique chemical and optical properties. As a sensitive luminescence material, they can be used as (bio probes in Förster Resonance Energy Transfer (FRET where trivalent lanthanide ions (La3+ act as energy donors. In this paper we present an efficient method to transfer ultrasmall (ca. 8 nm NaYF4 nanoparticles dispersed in organic solvent to an aqueous solution via oxidation of the oleic acid ligand. Nanoparticles were then functionalized with single strand DNA oligomers (ssDNA by inducing covalent bonds between surface carboxylic groups and a 5' amine modified-ssDNA. Hybridization with the 5' fluorophore (Cy5 modified complementary ssDNA strand demonstrated the specificity of binding and allowed the fine control over the distance between Eu3+ ions doped nanoparticle and the fluorophore by varying the number of the dsDNA base pairs. First, our results confirmed nonradiative resonance energy transfer and demonstrate the dependence of its efficiency on the distance between the donor (Eu3+ and the acceptor (Cy5 with sensitivity at a nanometre scale.

  10. DNA base pair resolution measurements using resonance energy transfer efficiency in lanthanide doped nanoparticles.

    Science.gov (United States)

    Delplanque, Aleksandra; Wawrzynczyk, Dominika; Jaworski, Pawel; Matczyszyn, Katarzyna; Pawlik, Krzysztof; Buckle, Malcolm; Nyk, Marcin; Nogues, Claude; Samoc, Marek

    2015-01-01

    Lanthanide-doped nanoparticles are of considerable interest for biodetection and bioimaging techniques thanks to their unique chemical and optical properties. As a sensitive luminescence material, they can be used as (bio) probes in Förster Resonance Energy Transfer (FRET) where trivalent lanthanide ions (La3+) act as energy donors. In this paper we present an efficient method to transfer ultrasmall (ca. 8 nm) NaYF4 nanoparticles dispersed in organic solvent to an aqueous solution via oxidation of the oleic acid ligand. Nanoparticles were then functionalized with single strand DNA oligomers (ssDNA) by inducing covalent bonds between surface carboxylic groups and a 5' amine modified-ssDNA. Hybridization with the 5' fluorophore (Cy5) modified complementary ssDNA strand demonstrated the specificity of binding and allowed the fine control over the distance between Eu3+ ions doped nanoparticle and the fluorophore by varying the number of the dsDNA base pairs. First, our results confirmed nonradiative resonance energy transfer and demonstrate the dependence of its efficiency on the distance between the donor (Eu3+) and the acceptor (Cy5) with sensitivity at a nanometre scale.

  11. IPAD: A unique approach to government/industry cooperation for technology development and transfer

    Science.gov (United States)

    Fulton, Robert E.; Salley, George C.

    1985-01-01

    A key element to improved industry productivity is effective management of Computer Aided Design / Computer Aided Manufacturing (CAD/CAM) information. To stimulate advancement, a unique joint government/industry project designated Integrated Programs for Aerospace-Vehicle Design (IPAD) was carried out from 1971 to 1984. The goal was to raise aerospace industry productivity through advancement of computer based technology to integrate and manage information involved in the design and manufacturing process. IPAD research was guided by an Industry Technical Advisory Board (ITAB) composed of over 100 representatives from aerospace and computer companies. The project complemented traditional NASA/DOD research to develop aerospace design technology and the Air Force's Integrated Computer Aided Manufacturing (ICAM) program to advance CAM technology. IPAD had unprecedented industry support and involvement and served as a unique approach to government industry cooperation in the development and transfer of advanced technology. The IPAD project background, approach, accomplishments, industry involvement, technology transfer mechanisms and lessons learned are summarized.

  12. Effect of pairing on nuclear dynamics

    International Nuclear Information System (INIS)

    Scamps, Guillaume

    2014-01-01

    Pairing correlations is an essential component for the description of the atomic nuclei. The effects of pairing on static property of nuclei are now well known. In this thesis, the effect of pairing on nuclear dynamics is investigated. Theories that includes pairing are benchmarked in a model case. The TDHF+BCS theory turns out to be a good compromise between the physics taken into account and the numerical cost. This TDHF+BCS theory was retained for realistic calculations. Nevertheless, the application of pairing in the BCS approximation may induce new problems due to (1) the particle number symmetry breaking, (2) the non-conservation of the continuity equation. These difficulties are analysed in detail and solutions are proposed. In this thesis, a 3 dimensional TDHF+BCS code is developed to simulate the nuclear dynamic. Applications to giant resonances show that pairing modify only the low lying peaks. The high lying collective components are only affected by the initial conditions. An exhaustive study of the giant quadrupole resonances with the TDHF+BCS theory is performed on more than 700 spherical or deformed nuclei. Is is shown that the TDHF+BCS theory reproduces well the collective energy of the resonance. After validation on the small amplitude limit problem, the approach was applied to study nucleon transfer in heavy ion reactions. A new method to extract transfer probabilities is introduced. It is demonstrated that pairing significantly increases the two-nucleon transfer probability. (author) [fr

  13. Charge Aspects of Composite Pair Superconductivity

    Science.gov (United States)

    Flint, Rebecca

    2014-03-01

    Conventional Cooper pairs form from well-defined electronic quasiparticles, making the internal structure of the pair irrelevant. However, in the 115 family of superconductors, the heavy electrons are forming as they pair and the internal pair structure becomes as important as the pairing mechanism. Conventional spin fluctuation mediated pairing cannot capture the direct transition from incoherent local moments to heavy fermion superconductivity, but the formation of composite pairs favored by the two channel Kondo effect can. These composite pairs are local d-wave pairs formed by two conduction electrons in orthogonal Kondo channels screening the same local moment. Composite pairing shares the same symmetries as magnetically mediated pairing, however, only composite pairing necessarily involves a redistribution of charge within the unit cell originating from the internal pair structure, both as a monopole (valence change) and a quadrupole effect. This redistribution will onset sharply at the superconducting transition temperature. A smoking gun test for composite pairing is therefore a sharp signature at Tc - for example, a cusp in the Mossbauer isomer shift in NpPd5Al2 or in the NQR shift in (Ce,Pu)CoIn5.

  14. A Precoded OFDMA System with User Cooperation

    NARCIS (Netherlands)

    Yu, Yao; Yatawatta, Sarod; Petropulu, Athina P.

    2010-01-01

    A new cooperative scheme for a two-user orthogonal frequency division multiple access (OFDMA) uplink communication scenario is proposed. Each user is equipped with one transmit/receive antenna. Before transmission, inter-block linear precoding is introduced to pairs of blocks. The cooperative

  15. Theory of pairing symmetry in the vortex states

    NARCIS (Netherlands)

    Yokoyama, Takehito; Ichioka, Yukio; Yanaka, Yukio; Golubov, Alexandre Avraamovitch

    2010-01-01

    We investigate pairing symmetry in an Abrikosov vortex and vortex lattice. It is shown that the Cooper pair wave function at the center of an Abrikosov vortex with vorticity m has a different parity with respect to frequency from that in the bulk if m is an odd number, while it has the same parity

  16. Pairing in Fermionic Systems Basic Concepts and Modern Applications

    CERN Document Server

    Clark, John W; Alford, Mark

    2006-01-01

    Cooper pairing of fermions is a profound phenomenon that has become very important in many different areas of physics in the recent past. This book brings together, for the first time, experts from various fields involving Cooper pairing, at the level of BCS theory and beyond, including the study of novel states of matter such as ultracold atomic gases, nuclear systems at the extreme, and quark matter with application to neutron stars. Cross-disciplinary in nature, the book will be of interest to physicists in many different specialties, including condensed matter, nuclear, high-energy, and as

  17. Observation of preformed electron-hole Cooper pairs in highly excited ZnO

    NARCIS (Netherlands)

    Versteegh, M.A.M.; van Lange, A.J.; Stoof, H.T.C.; Dijkhuis, J.I.

    2012-01-01

    Electrons and holes in a semiconductor form hydrogen-atom-like bound states, called excitons. At high electron-hole densities the attractive Coulomb force becomes screened and excitons can no longer exist. Bardeen-Cooper-Schrieffer theory predicts that at such high densities co-operative many-body

  18. Pairing induced superconductivity in holography

    Science.gov (United States)

    Bagrov, Andrey; Meszena, Balazs; Schalm, Koenraad

    2014-09-01

    We study pairing induced superconductivity in large N strongly coupled systems at finite density using holography. In the weakly coupled dual gravitational theory the mechanism is conventional BCS theory. An IR hard wall cut-off is included to ensure that we can controllably address the dynamics of a single confined Fermi surface. We address in detail the interplay between the scalar order parameter field and fermion pairing. Adding an explicitly dynamical scalar operator with the same quantum numbers as the fermion-pair, the theory experiences a BCS/BEC crossover controlled by the relative scaling dimensions. We find the novel result that this BCS/BEC crossover exposes resonances in the canonical expectation value of the scalar operator. This occurs not only when the scaling dimension is degenerate with the Cooper pair, but also with that of higher derivative paired operators. We speculate that a proper definition of the order parameter which takes mixing with these operators into account stays finite nevertheless.

  19. Instantons in lepton pair production

    International Nuclear Information System (INIS)

    Brandenburg, A.; Ringwald, A.; Utermann, A.

    2006-05-01

    We consider QCD instanton-induced contributions to lepton pair production in hadron-hadron collisions. We relate these contributions to those known from deep inelastic scattering and demonstrate that they can be calculated reliably for sufficiently large momentum transfer. We observe that the instanton contribution to the angular distribution of the lepton pairs at finite momentum transfer strongly violates the Lam-Tung relation - a relation between coefficient functions of the angular distribution which is valid within the framework of ordinary perturbation theory. The drastic violation of this relation, as seen in experimental data, might be related to such instanton-induced effects. (Orig.)

  20. Selection rules for Cooper pairing in two-dimensional interfaces and sheets

    Science.gov (United States)

    Scheurer, Mathias S.; Agterberg, Daniel F.; Schmalian, Jörg

    2017-12-01

    Thin sheets deposited on a substrate and interfaces of correlated materials offer a plethora of routes towards the realization of exotic phases of matter. In these systems, inversion symmetry is broken which strongly affects the properties of possible instabilities—in particular in the superconducting channel. By combining symmetry and energetic arguments, we derive general and experimentally accessible selection rules for Cooper instabilities in noncentrosymmetric systems, which yield necessary and sufficient conditions for spontaneous time-reversal-symmetry breaking at the superconducting transition and constrain the orientation of the triplet vector. We discuss in detail the implications for various different materials. For instance, we conclude that the pairing state in thin layers of Sr2RuO4 must, as opposed to its bulk superconducting state, preserve time-reversal symmetry with its triplet vector being parallel to the plane of the system. All triplet states of this system allowed by the selection rules are predicted to display topological Majorana modes at dislocations or at the edge of the system. Applying our results to the LaAlO3/SrTiO3 heterostructures, we find that while the condensates of the (001) and (110) oriented interfaces must be time-reversal symmetric, spontaneous time-reversal-symmetry breaking can only occur for the less studied (111) interface. We also discuss the consequences for thin layers of URu2Si2 and UPt3 as well as for single-layer FeSe. On a more general level, our considerations might serve as a design principle in the search for time-reversal-symmetry-breaking superconductivity in the absence of external magnetic fields.

  1. Evaluating the Cooperative Component in Cooperative Learning: A Quasi-Experimental Study

    Science.gov (United States)

    Emerson, Tisha L. N.; English, Linda K.; McGoldrick, KimMarie

    2015-01-01

    In this study, the authors employed a quasi-experimental research design to examine the efficacy of a cooperative learning pedagogy (i.e., think-pair-share exercises) integrated into sections of microeconomic principles. Materials, exercises, and assessment instruments for all study sections are identical except for the nature of the…

  2. The history and perspective of Romania-USA cooperation in the field of technologic transfer of TRIGA reactor concept

    International Nuclear Information System (INIS)

    Ciocaanescu, M.; Ionescu, M.

    1996-01-01

    The cooperation between Romania and the USA in the field of technologic transfer of nuclear research reactor technology began with the steady state 14 MW t TRIGA reactor, installed at INR Pitesti, Romania. It is the first in the range of TRIGA reactors proposed as a materials testing reactor. The first criticality was reached in November 19, 1979 and first operation at 14 MW t level was in February 1980. The paper will present the short history of this cooperation and the perspective for a new cooperation for building a Nuclear Heating Plant using the TRIGA reactor concept for demonstration purpose. The energy crisis is a world-wide problem which affects each country in different ways because the resources and the consumption are unfairly distributed. World-wide research points out that the fossil fuel sources are not to be considered the main energy sources for the long term as they are limited

  3. Transfer of energy between a pair of molecules near a plasmonic core-shell nanoparticle: Tunability and sensing

    Energy Technology Data Exchange (ETDEWEB)

    Daneshfar, Nader, E-mail: ndaneshfar@gmail.com, E-mail: ndaneshfar@razi.ac.ir; Yavari, Asghar [Department of Physics, Razi University, Kermanshah (Iran, Islamic Republic of)

    2016-05-15

    Our model is applied to the calculation of interaction energy between a pair of dipolar molecules (point dipoles) in the vicinity of a nanoshell monomer with core-shell structure, based on the dipole quasi-electrostatic theory of classical electrodynamics and using the Drude and Maxwell-Garnett model. In other words, this work discusses the intermolecular energy transfer from a donor molecule to an acceptor molecule near a spherical nanoparticle that is important for practical applications like sensing. It is shown that the proximity of plasmonic nanoparticles can have a strong effect on the energy transfer between molecules. In addition to the influence of the size, composition, embedding medium, and the filling fraction of doped particles on the interaction energy, the contribution of the dipolar, quadrupolar, octupolar, hexadecapolar, triakontadipolar, and higher order multipole interactions is presented and analyzed. Briefly, we will show that it is possible to achieve enhanced energy transfer by manipulation of different parameters as mentioned above.

  4. Cooperative newsvendor games : a review

    NARCIS (Netherlands)

    Montrucchio, L.; Norde, H.; Ozen, U.; Scarsini, M.; Slikker, M.; Choi, T.-M.

    2012-01-01

    In this survey, we review some of the main contributions to the cooperative approach of newsvendor situations. We show how newsvendor situations with several retailers can be modeled as a transferable-utility cooperative game and we concentrate on one solution concept: the core. First, we examine

  5. A Taste of Cooperativeness within an Elementary School.

    Science.gov (United States)

    McElroy, Karen B.

    1989-01-01

    The process of implementing cooperative learning techniques in an elementary school in Montgomery County, Maryland, is described. Discussed are: learning techniques used, such as Student Teams Achievement Divisions, Round Table, Think-Pair-Share, and the Trading Game; student and teacher reactions to cooperative learning; teacher recommendations;…

  6. The transfer of nuclear technology: necessities and limitations

    International Nuclear Information System (INIS)

    Haunschild, H.-H.

    1978-01-01

    Political and economical importance of the transfer of nuclear technologies to less developed countries is examined. Energy needs of the world create the necessity of technology transfer. Three levels are distinguished: 1) Basic elements of cooperation are agreed between the two Governments, 2) scientific cooperation and 3) industrial cooperation. Technology transfer is more than mere technology export. Limitations of nuclear technology transfer are: the lack of infrastructure, the high price of a nuclear power station but above all the problem of proliferation. In conclusion the solution of international problems of nuclear energy is the concept of cooperation on the basis of equal rights

  7. Enhancement of international cooperation and experience exchange - international and regional cooperation in nuclear technology

    International Nuclear Information System (INIS)

    Henderson, R.R.

    1988-01-01

    This paper will explore methods that have been effective in accomplishing broad-based technology transfer relationships between international commercial nuclear organizations, and have enhanced the benefits from such relationships through mutual participation in the development of new technology. The factors involved in accomplishing technology transfer will be examined based on the 25 years of Westinghouse experience in establishing successful nuclear technology relationships with over 20 different associates world-wide. This will include information pertaining to organization, training, consultation, technical information transmission, and other important aspects of technology transfer. Additionally, the methodology of enhancing and increasing the benefits of technology transfer through cooperative development programs as produced and promoted by Westinghouse with its associates will be examined. This will include reviews of several significant cooperative programs, such as the programs for the Advanced Pressurized Water Reactor and the Integrated Protection and Control Systems for future plants

  8. Transfer of knowledge in international cooperation: the Farmanguinhos - SMM case.

    Science.gov (United States)

    Silva, Samuel Araujo Gomes da; Duarte, Roberto Gonzalez; Castro, José Márcio de

    2017-01-01

    To analyze the influence of four mechanisms of knowledge transfer (training, technical visits, expatriation, and standard operating procedures) on the different dimensions (potential and realized) of absorptive capacity in international technical cooperation. We examine the case of implementation of the Sociedade Moçambicana de Medicamentos. Data have been collected using semi-structured interviews (applied to 21 professionals of the Sociedade Moçambicana de Medicamentos, Farmanguinhos, FIOCRUZ, and Itamaraty) and official documents. The data of the interviews have been submitted to content analysis, using the software NVivo. Training and technical visits directly influenced the acquisition and, partly, the assimilation of knowledge. Expatriation contributed with the transformation of this knowledge from the development and refinement of operational routines. Finally, the definition of standard operating procedures allowed the Mozambican technicians to be the actors of the transformation of the knowledge previously acquired and assimilated and, at the same time, it laid the foundations for a future exploration of the knowledge. Training and technical visits mainly influence the potential absorptive capacity, while expatriation and standard operating procedures most directly affect the realized absorptive capacity.

  9. Solutions for cooperative games with and without transferable utility

    NARCIS (Netherlands)

    Suzuki, T.

    2015-01-01

    When individuals generate benefits from their cooperation, allocation problems may occur regarding how much of the benefit from the cooperation each individual should take. In many economic situations, defining the contribution of each individual in a fair way is essential. This thesis is on

  10. What drives cooperative breeding?

    Directory of Open Access Journals (Sweden)

    Walter D Koenig

    2017-06-01

    Full Text Available Cooperative breeding, in which more than a pair of conspecifics cooperate to raise young at a single nest or brood, is widespread among vertebrates but highly variable in its geographic distribution. Particularly vexing has been identifying the ecological correlates of this phenomenon, which has been suggested to be favored in populations inhabiting both relatively stable, productive environments and in populations living under highly variable and unpredictable conditions. Griesser et al. provide a novel approach to this problem, performing a phylogenetic analysis indicating that family living is an intermediate step between nonsocial and cooperative breeding birds. They then examine the ecological and climatic conditions associated with these different social systems, concluding that cooperative breeding emerges when family living is favored in highly productive environments, followed secondarily by selection for cooperative breeding when environmental conditions deteriorate and within-year variability increases. Combined with recent work addressing the fitness consequences of cooperative breeding, Griesser et al.'s contribution stands to move the field forward by demonstrating that the evolution of complex adaptations such as cooperative breeding may only be understood when each of the steps leading to it are identified and carefully integrated.

  11. Separation of photo-induced radical pair in cryptochrome to a functionally critical distance

    DEFF Research Database (Denmark)

    Solov'yov, Ilia; Domratcheva, Tatiana; Schulten, Klaus

    2014-01-01

    Cryptochrome is a blue light receptor that acts as a sensor for the geomagnetic field and assists many animals in long-range navigation. The magnetoreceptor function arises from light-induced formation of a radical pair through electron transfer between a flavin cofactor (FAD) and a triad...... of tryptophan residues. Here, this electron transfer is investigated by quantum chemical and classical molecular dynamics calculations. The results reveal how sequential electron transfer, assisted by rearrangement of polar side groups in the cryptochrome interior, can yield a FAD-Trp radical pair state...... step can overcome in speed both recombination (electron back-transfer) and proton transfer involving the radical pair reached after primary electron transfer....

  12. Amperean Pairing and the Pseudogap Phase of Cuprate Superconductors

    Science.gov (United States)

    Lee, Patrick A.

    2014-07-01

    The enigmatic pseudogap phase in underdoped cuprate high-Tc superconductors has long been recognized as a central puzzle of the Tc problem. Recent data show that the pseudogap is likely a distinct phase, characterized by a medium range and quasistatic charge ordering. However, the origin of the ordering wave vector and the mechanism of the charge order is unknown. At the same time, earlier data show that precursive superconducting fluctuations are also associated with this phase. We propose that the pseudogap phase is a novel pairing state where electrons on the same side of the Fermi surface are paired, in strong contrast with conventional Bardeen-Cooper-Schrieffer theory which pairs electrons on opposite sides of the Fermi surface. In this state the Cooper pair carries a net momentum and belongs to a general class called pair density wave. The microscopic pairing mechanism comes from a gauge theory formulation of the resonating valence bond (RVB) picture, where spinons traveling in the same direction feel an attractive force in analogy with Ampere's effects in electromagnetism. We call this Amperean pairing. Charge order automatically appears as a subsidiary order parameter even when long-range pair order is destroyed by phase fluctuations. Our theory gives a prediction of the ordering wave vector which is in good agreement with experiment. Furthermore, the quasiparticle spectrum from our model explains many of the unusual features reported in photoemission experiments. The Fermi arc, the unusual way the tip of the arc terminates, and the relation of the spanning vector of the arc tips to the charge ordering wave vector also come out naturally. Finally, we propose an experiment that can directly test the notion of Amperean pairing.

  13. 259 “Team Pair Solo” Cooperative Learning and Personality Type ...

    African Journals Online (AJOL)

    User

    learning strategy and students' personality type on achievement and attitude to Chemistry. 175 SS2 ... There is increasing concern among practitioners and educational researchers about the .... Teachers' role in a cooperative learning classroom involves a careful design of meaningful ..... Classroom Management. Harry K.

  14. The Effect of Cooperative Learning Model Script and Think-Pair-Share to Critical Thinking Skills, Social Attitude and Learning Outcomes Cognitive Biology of multiethnic High School Students

    Directory of Open Access Journals (Sweden)

    Didimus Tanah Boleng

    2015-03-01

    Full Text Available Pengaruh Model Pembelajaran Cooperative Script dan Think-Pair-Share terhadap Keterampilan Berpikir Kritis, Sikap Sosial, dan Hasil Belajar Kognitif Biologi Siswa SMA Multietnis   Abstract: Biological learning process with multiethnic students requires a learning models which allow students to work independently, to work together in small groups, and to share with other groups. The purpose of this study was to determine the effect of learning models, ethnicity, and the interaction of learning model and ethnic on critical thinking skills, social attitudes, and cognitive achievement. This quasi experimental study was conducted in 11th grade of Natural Science Class Highschool students with six ethnicaly and Junior Highschool National score groups consisted of 132 samples. The results of Covarian Analysis showed that the learning models significantly affected the social attitudes and increased the critical thinking skills and cognitive achievement. Ethnicity significantly affected the social attitudes and cognitive achievement. Interaction of learning models and ethnicity significantly affected students social attitudes. Key Words: cooperative script, think-pair-share, critical thinking skills, social attitudes, biology cognitive achievement, multiethnic students Abstrak: Pengelolaan proses pembelajaran biologi pada siswa multietnis memerlukan model pembelajaran yang memungkinkan siswa bekerja mandiri, bekerja sama dalam kelompok kecil, dan berbagi dengan kelompok lain. Tujuan penelitian ini untuk mengetahui pengaruh model pembelajaran, etnis, serta interaksi model pembelajaran dan etnis terhadap keterampilan berpikir kritis, sikap sosial, dan hasil belajar kognitif biologi siswa. Penelitian eksperimen semu ini dilakukan di kelas XI IPA SMA dengan sampel sebanyak 132 orang siswa terbagi dalam enam kelas yang homogen berdasarkan etnis dan nilai ujian nasional SMP siswa. Hasil analisis data dengan menggunakan Analisis Kovarian menunjukkan bahwa model

  15. Transferability of antibody pairs from ELISA to fiber optic surface plasmon resonance for infliximab detection

    Science.gov (United States)

    Van Stappen, Thomas; Lu, Jiadi; Bloemen, Maarten; Geukens, Nick; Spasic, Dragana; Delport, Filip; Verbiest, Thierry; Lammertyn, Jeroen; Gils, Ann

    2015-03-01

    Tumor necrosis factor (TNF)-alpha is a pleiotropic cytokine up-regulated in inflammatory bowel disease, rheumatoid arthritis and psoriasis. The introduction of anti-TNF drugs such as infliximab has revolutionized the treatment of these diseases. Recently, therapeutic drug monitoring (TDM) of infliximab has been introduced in clinical decision making to increase cost-efficiency. Nowadays, TDM is performed using radio-immunoassays, homogeneous mobility shift assays or ELISA. Unfortunately, these assays do not allow for in situ treatment optimization, because of the required sample transportation to centralized laboratories and the subsequent assay execution time. In this perspective, we evaluated the potential of fiber optic-surface plasmon resonance (FO-SPR). To achieve this goal, a panel of 55 monoclonal anti-infliximab antibodies (MA-IFX) was developed and characterized in-house, leading to the identification of nine different clusters. Based on this high diversity, 22 antibody pairs were selected and tested for their reactivity towards IFX, using one MA-IFX as capture and one MA-IFX for detection, in a sandwich type ELISA and FO-SPR. This study showed that the reactivity towards IFX of each antibody pair in ELISA is highly similar to its reactivity on FO-SPR, indicating that antibody pairs are easily transferable between both platforms. Given the fact that FO-SPR shows the potential for miniaturization and fast assay time, it can be considered a highly promising platform for on-site infliximab monitoring.

  16. Spin-Triplet Pairing Induced by Spin-Singlet Interactions in Noncentrosymmetric Superconductors

    Science.gov (United States)

    Matsuzaki, Tomoaki; Shimahara, Hiroshi

    2017-02-01

    In noncentrosymmetric superconductors, we examine the effect of the difference between the intraband and interband interactions, which becomes more important when the band splitting increases. We define the difference ΔVμ between their coupling constants, i.e., that between the intraband and interband hopping energies of intraband Cooper pairs. Here, the subscript μ of ΔVμ indicates that the interactions scatter the spin-singlet and spin-triplet pairs when μ = 0 and μ = 1,2,3, respectively. It is shown that the strong antisymmetric spin-orbit interaction reverses the target spin parity of the interaction: it converts the spin-singlet and spin-triplet interactions represented by ΔV0 and ΔVμ>0 into effective spin-triplet and spin-singlet pairing interactions, respectively. Hence, for example, triplet pairing can be induced solely by the singlet interaction ΔV0. We name the pairing symmetry of the system after that of the intraband Cooper pair wave function, but with an odd-parity phase factor excluded. The pairing symmetry must then be even, even for the triplet component, and the following results are obtained. When ΔVμ is small, the spin-triplet p-wave interactions induce spin-triplet s-wave and spin-triplet d-wave pairings in the regions where the repulsive singlet s-wave interaction is weak and strong, respectively. When ΔV0 is large, a repulsive interband spin-singlet interaction can stabilize spin-triplet pairing. When the Rashba interaction is adopted for the spin-orbit interaction, the spin-triplet pairing interactions mediated by transverse magnetic fluctuations do not contribute to triplet pairing.

  17. Decay time shortening of fluorescence from donor-acceptor pair proteins using ultrafast time-resolved fluorescence resonance energy transfer spectroscopy

    International Nuclear Information System (INIS)

    Baba, Motoyoshi; Suzuki, Masayuki; Ganeev, Rashid A.; Kuroda, Hiroto; Ozaki, Tsuneyuki; Hamakubo, Takao; Masuda, Kazuyuki; Hayashi, Masahiro; Sakihama, Toshiko; Kodama, Tatsuhiko; Kozasa, Tohru

    2007-01-01

    We improved an ultrafast time-resolved fluorescence resonance energy transfer (FRET) spectroscopy system and measured directly the decrease in the fluorescence decay time of the FRET signal, without any entanglement of components in the picosecond time scale from the donor-acceptor protein pairs (such as cameleon protein for calcium ion indicator, and ligand-activated GRIN-Go proteins pair). The drastic decrease in lifetime of the donor protein fluorescence under the FRET condition (e.g. a 47.8% decrease for a GRIN-Go protein pair) proves the deformation dynamics between donor and acceptor fluorescent proteins in an activated state of a mixed donor-acceptor protein pair. This study is the first clear evidence of physical contact of the GRIN-Go proteins pair using time-resolved FRET system. G protein-coupled receptors (GPCRs) are the most important protein family for the recognition of many chemical substances at the cell surface. They are the targets of many drugs. Simultaneously, we were able to observe the time-resolved spectra of luminous proteins at the initial stage under the FRET condition, within 10 ns from excitation. This new FRET system allows us to trace the dynamics of the interaction between proteins at the ligand-induced activated state, molecular structure change and combination or dissociation. It will be a key technology for the development of protein chip technology

  18. THINK-PAIR-SHARE: A TECNIQUE TO ENHANCE STUDENTS’ WRITING SKILL

    OpenAIRE

    Okta Ika Rahmawati

    2017-01-01

    Abstract: Think – Pair Share: A Tecnique to Enhance Students’ Writing Skill. This article refers to a classroom action research on teaching writing by implementing Think-Pair-Share at High School in Bojonegoro. Think-Pair-Share Technique is a kind of cooperative learning technique. This technique encourages students to actively involve in the learning process since they have to discuss with their partner about the material being learned. The subject of the study was the tenth-grade students o...

  19. Cooperative motion of intrinsic and actuated semiflexible swimmers

    Science.gov (United States)

    Llopis, I.; Pagonabarraga, I.; Cosentino Lagomarsino, M.; Lowe, C. P.

    2013-03-01

    We examine the phenomenon of hydrodynamic-induced cooperativity for pairs of flagellated micro-organism swimmers, of which spermatozoa cells are an example. We consider semiflexible swimmers, where inextensible filaments are driven by an internal intrinsic force and torque-free mechanism (intrinsic swimmers). The velocity gain for swimming cooperatively, which depends on both the geometry and the driving, develops as a result of the near-field coupling of bending and hydrodynamic stresses. We identify the regimes where hydrodynamic cooperativity is advantageous and quantify the change in efficiency. When the filaments' axes are parallel, hydrodynamic interaction induces a directional instability that causes semiflexible swimmers that profit from swimming together to move apart from each other. Biologically, this implies that flagella need to select different synchronized collective states and to compensate for directional instabilities (e.g., by binding) in order to profit from swimming together. By analyzing the cooperative motion of pairs of externally actuated filaments, we assess the impact that stress distribution along the filaments has on their collective displacements.

  20. The impact of size of cooperative group on achievement, social support, and self-esteem.

    Science.gov (United States)

    Bertucci, Andrea; Conte, Stella; Johnson, David W; Johnson, Roger T

    2010-01-01

    The effect of cooperative learning in pairs and groups of 4 and in individualistic learning were compared on achievement, social support, and self-esteem. Sixty-two Italian 7th-grade students with no previous experience with cooperative learning were assigned to conditions on a stratified random basis controlling for ability, gender, and self-esteem. Students participated in 1 instructional unit for 90 min for 6 instructional days during a period of about 6 weeks. The results indicate that cooperative learning in pairs and 4s promoted higher achievement and greater academic support from peers than did individualistic learning. Students working in pairs developed a higher level of social self-esteem than did students learning in the other conditions.

  1. NetCooperate: a network-based tool for inferring host-microbe and microbe-microbe cooperation.

    Science.gov (United States)

    Levy, Roie; Carr, Rogan; Kreimer, Anat; Freilich, Shiri; Borenstein, Elhanan

    2015-05-17

    Host-microbe and microbe-microbe interactions are often governed by the complex exchange of metabolites. Such interactions play a key role in determining the way pathogenic and commensal species impact their host and in the assembly of complex microbial communities. Recently, several studies have demonstrated how such interactions are reflected in the organization of the metabolic networks of the interacting species, and introduced various graph theory-based methods to predict host-microbe and microbe-microbe interactions directly from network topology. Using these methods, such studies have revealed evolutionary and ecological processes that shape species interactions and community assembly, highlighting the potential of this reverse-ecology research paradigm. NetCooperate is a web-based tool and a software package for determining host-microbe and microbe-microbe cooperative potential. It specifically calculates two previously developed and validated metrics for species interaction: the Biosynthetic Support Score which quantifies the ability of a host species to supply the nutritional requirements of a parasitic or a commensal species, and the Metabolic Complementarity Index which quantifies the complementarity of a pair of microbial organisms' niches. NetCooperate takes as input a pair of metabolic networks, and returns the pairwise metrics as well as a list of potential syntrophic metabolic compounds. The Biosynthetic Support Score and Metabolic Complementarity Index provide insight into host-microbe and microbe-microbe metabolic interactions. NetCooperate determines these interaction indices from metabolic network topology, and can be used for small- or large-scale analyses. NetCooperate is provided as both a web-based tool and an open-source Python module; both are freely available online at http://elbo.gs.washington.edu/software_netcooperate.html.

  2. PENINGKATAN KEMAMPUAN REPRESENTASI MATEMATIS MELALUI MODEL PEMBELAJARAN KOOPERATIF THINK PAIR SHARE

    Directory of Open Access Journals (Sweden)

    Yunni Arnidha

    2016-04-01

    Full Text Available This study aims to analyze the improvement of students’ mathematicalrepresentation achievement taught by cooperative learning think pair share andstudents’ mathematical representation achievement taught by conventional method.This study is quasi experimental with Pretest –Posttest Control Group Design. Thisstudy conducted at SMPN 3 Pringsewu. The population was all of the eight gradestudents at SMPN 3 Pringsewu, with the samples of this study consists of the VIII-2class as the experiment class and VIII-5 class as the control class. To obtain thedata, it used mathematical representation achievement test instrument. The dataanalysis was conducted to know the average difference between two samples usingt-test. The result showed the improvement of mathematical representationachievement taught by cooperative learning think pair share is better than thestudents taught by conventional learning method.Keywords: think pair share model, conventional learning method,Mathematical representation

  3. The Role of Broken Cooper Pairs in Warm Nuclei

    International Nuclear Information System (INIS)

    Guttormsen, M.; Chankova, R.; Larsen, A.C.; Rekstad, J.; Siem, S.; Syed, N.U.H.; Agvaanluvsan, U.; Schiller, A.; Voinov, A.

    2007-01-01

    In order to understand warm nuclei and describe the underlying microscopic structure, entropy is measured for several even-even and odd-mass nuclei. Mid-shell nuclei show significant odd-even entropy differences interpreted as the single-particle entropy introduced by the valence nucleon. A method to extract critical temperatures for the pair breaking process is demonstrated. (author)

  4. International technology transfer

    International Nuclear Information System (INIS)

    Kwon, Won Gi

    1991-11-01

    This book introduces technology progress and economic growth, theoretical consideration of technology transfer, policy and mechanism on technology transfer of a developed country and a developing country, reality of international technology transfer technology transfer and industrial structure in Asia and the pacific region, technology transfer in Russia, China and Eastern Europe, cooperation of science and technology for development of Northeast Asia and strategy of technology transfer of Korea.

  5. The Effects of Temperature Priming on Cooperation in the Iterated Prisoner's Dilemma

    Directory of Open Access Journals (Sweden)

    Simon Storey

    2013-01-01

    Full Text Available Based on initial research findings by Williams and Bargh (2008 and Kang, Williams, Clark, Gray and Bargh (2011 on the interaction between interpersonal and physical warmth, theoretical models such as cognitive scaffolding and the importance of evaluations of interpersonal warmth in trust-based decisions, this experiment investigated the effect of temperature priming on 30 pairs of British university students with hot and cold objects on frequency of cooperation in a game of iterated Prisoner's Dilemma. Participants were found to cooperate significantly more frequently when primed with hot objects than with cold objects, supporting the assertion that physical warmth sensation positively affects interpersonal trust evaluation. No support was found for the prediction that male-male pairs would cooperate less than female-female pairs. The implications of these findings to evolutionary and developmental theories of interpersonal warmth are discussed.

  6. Emergency transfer tube closure and process for sealing transfer tube under emergency conditions

    International Nuclear Information System (INIS)

    Hardin, R.T. Jr.; Marshall, J.R.

    1987-01-01

    In a nuclear fuel reactor well that includes a transfer tube projecting outwardly from wall thereof, the transfer tube is described having a first closure assembly. The transfer tube has a circumferential flange extending outwardly laterally therefrom, an emergency transfer tube closure therefor comprising; a pair of elongated, vertically-extending U-shaped guides, one U-shaped guide disposed laterally on each side of the transfer tube, each of the U-shaped guides comprising a base and laterally extending flanges thereon, the U-shaped guides having their open ends facing each other, a closure plate, having a surface facing the circumferential flange greater in area than the area circumscribed by the outer circumference of the circumferential flange, vertically disposed the U-shaped guides, the closure plate normally being disposed in a vertical plane just slightly in front of the vertical plane of the circumferential flange, two pairs of rollers, one pair of which is rotatably mounted on each side of the closure plate adjacent the U-shaped guides, riding on the inner portion of each of the flanges of each of the U-shaped guides. Each of the U-shaped guides is provided with a pair of spatially disposed openings on a flange thereof adjacent the wall of the nuclear fuel reactor well, each of the pairs of openings being disposed on each of the U-shaped guides a distance equal to the distance between the center lines of the corresponding pair of rollers riding within the U-shaped guides, each of the openings being sufficiently large to receive a corresponding roller of the pairs of rollers in the U-shaped guides. The openings is shaped on the flanges of the U-shaped guides so that when the pairs of rollers are disposed therein, the face of the closure plate will be in sealing engagement with the circumferential flange of the transfer tube

  7. Determination of constants of factorized pairing force from conservation laws

    International Nuclear Information System (INIS)

    Voronkov, Yu.P.; Mikhajlov, V.M.

    1975-01-01

    The constants of a factorized interaction in the particle-particle channel are evaluated on the basis of average field parameters and Cooper pairing. The relations between the constants of multipole particle-particle forces are derived for the spherical nuclei. The constants of the quadrupole pairing are obtained for deformed nuclei from the angular momentum conservation law. The calculated constants are compared with empiricalones

  8. Can tautomerization of the A·T Watson-Crick base pair via double proton transfer provoke point mutations during DNA replication? A comprehensive QM and QTAIM analysis.

    Science.gov (United States)

    Brovarets, Ol'ha O; Hovorun, Dmytro M

    2014-01-01

    Trying to answer the question posed in the title, we have carried out a detailed theoretical investigation of the biologically important mechanism of the tautomerization of the A·T Watson-Crick DNA base pair, information that is hard to establish experimentally. By combining theoretical investigations at the MP2 and density functional theory levels of QM theory with quantum theory of atoms in molecules analysis, the tautomerization of the A·T Watson-Crick base pair by the double proton transfer (DPT) was comprehensively studied in vacuo and in the continuum with a low dielectric constant (ϵ = 4) corresponding to a hydrophobic interfaces of protein-nucleic acid interactions. Based on the sweeps of the electron-topological, geometric, and energetic parameters, which describe the course of the tautomerization along its intrinsic reaction coordinate (IRC), it was proved that the A·T → A(∗)·T(∗) tautomerization through the DPT is a concerted (i.e. the pathway without an intermediate) and asynchronous (i.e. protons move with a time gap) process. The limiting stage of this phenomenon is the final PT along the N6H⋯O4 hydrogen bond (H-bond). The continuum with ϵ = 4 does not affect qualitatively the course of the tautomerization reaction: similar to that observed in vacuo, it proceeds via a concerted asynchronous process with the same structure of the transition state (TS). For the first time, the nine key points along the IRC of the A·T base pair tautomerization, which could be considered as electron-topological "fingerprints" of a concerted asynchronous process of the tautomerization via the DPT, have been identified and fully characterized. These nine key points have been used to define the reactant, TS, and product regions of the DPT in the A·T base pair. Considering the energy dependence of each of the three H-bonds, which stabilize the Watson-Crick and Löwdin's base pairs, along the IRC of the tautomerization, it was found that all these H

  9. 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.

  10. Technology transfer and knowledge management in cooperation networks: the Airzone case; Transferencia y gestion del conocimiento en las redes de cooperacion: El caso de Airzone

    Energy Technology Data Exchange (ETDEWEB)

    Benavides Velasco, C. A.; Quintana Garcia, C.

    2007-07-01

    This paper highlights the importance of cooperation networks between the public system of R and D and industry to promote technology transfer, knowledge management, and the consolidation and growth of new technology firms. Through the case of Air zone,his paper shows the significance of collaboration agreements between University and industry to enhance technology transfer and the success of entrepreneurial projects. (Author) 28 refs.

  11. Distributed wireless quantum communication networks with partially entangled pairs

    International Nuclear Information System (INIS)

    Yu Xu-Tao; Zhang Zai-Chen; Xu Jin

    2014-01-01

    Wireless quantum communication networks transfer quantum state by teleportation. Existing research focuses on maximal entangled pairs. In this paper, we analyse the distributed wireless quantum communication networks with partially entangled pairs. A quantum routing scheme with multi-hop teleportation is proposed. With the proposed scheme, is not necessary for the quantum path to be consistent with the classical path. The quantum path and its associated classical path are established in a distributed way. Direct multi-hop teleportation is conducted on the selected path to transfer a quantum state from the source to the destination. Based on the feature of multi-hop teleportation using partially entangled pairs, if the node number of the quantum path is even, the destination node will add another teleportation at itself. We simulated the performance of distributed wireless quantum communication networks with a partially entangled state. The probability of transferring the quantum state successfully is statistically analyzed. Our work shows that multi-hop teleportation on distributed wireless quantum networks with partially entangled pairs is feasible. (general)

  12. Cooperative learning as an approach to pedagogy.

    Science.gov (United States)

    Nolinske, T; Millis, B

    1999-01-01

    Lecture-based pedagogical approaches cannot adequately prepare students in professional and technical occupational therapy programs. Faculty members in other disciplines are turning to a well-known and well-researched teaching approach called cooperative learning, which is more carefully structured and defined than most other forms of small group learning. Cooperative learning includes several key principles: positive interdependence, individual responsibility, appropriate grouping, group maintenance, cooperative skills, and promotive (interaction) time. This article provides ideas for managing the classroom with cooperative learning activities and describes eight of them: Three-Step Interview, Roundtable, Think-Pair-Share, Structured Problem Solving, Send/Pass-a-Problem, Generic Question Stems, Double Entry Journal, and Dyadic Essay Confrontation. Each activity is applied to content embedded in professional and technical occupational therapy curricula. A cooperative learning approach to evaluating learning is also presented.

  13. Entanglement transfer between bipartite systems

    International Nuclear Information System (INIS)

    Bougouffa, Smail; Ficek, Zbigniew

    2012-01-01

    The problem of a controlled transfer of an entanglement initially encoded into two two-level atoms that are successively sent through two single-mode cavities is investigated. The atoms and the cavity modes form a four-qubit system and we demonstrate the conditions under which the initial entanglement encoded into the atoms can be completely transferred to other pairs of qubits. We find that in the case of non-zero detuning between the atomic transition frequencies and the cavity mode frequencies, no complete transfer of the initial entanglement is possible to any of the other pairs of qubits. In the case of exact resonance and equal coupling strengths of the atoms to the cavity modes, an initial maximally entangled state of the atoms can be completely transferred to the cavity modes. Complete transfer of the entanglement is restricted to the cavity modes, with transfer to the other pairs being limited to 50%. We find that complete transfer of an initial entanglement to other pairs of qubits may take place if the initial state is not the maximally entangled state and the atoms couple to the cavity modes with unequal strengths. Depending on the ratio between the coupling strengths, optimal entanglement can be created between the atoms and one of the cavity modes.

  14. Pair transfer processes probed at deep sub barrier energies

    International Nuclear Information System (INIS)

    Corradi, L.; Mason, P.; Fioretto, E.; Michelagnoli, C.; Stefanini, A.M.; Valiente-Dobon, J.J.; Szinler, S.; Jelavic-Malenica, D.; Soic, N.; Pollarolo, G.; Farnea, E.; Montagnoli, G.; Montanari, D.; Scarlassara, F.; Ur, C.A.; Gadea, A.; Haas, F.; Marginean, N.

    2011-01-01

    Multinucleon transfer cross sections in the system 40 Ca+ 96 Zr have been measured at bombarding energies ranging from the Coulomb barrier to ∼ 25% below. Target-like (lighter) recoils in inverse kinematics have been completely identified in A,Z and Q-value with the large solid angle magnetic spectrometer PRISMA. The experimental slopes of the neutron transfer probabilities at large internuclear separation are consistent with the values derived from the binding energies. A phenomenological interpretation of the transfer probabilities indicates the presence of enhanced values for the even number of neutron transfers. (authors)

  15. Molecular cooperativity and compatibility via full atomistic simulation

    Science.gov (United States)

    Kwan Yang, Kenny

    Civil engineering has customarily focused on problems from a large-scale perspective, encompassing structures such as bridges, dams, and infrastructure. However, present day challenges in conjunction with advances in nanotechnology have forced a re-focusing of expertise. The use of atomistic and molecular approaches to study material systems opens the door to significantly improve material properties. The understanding that material systems themselves are structures, where their assemblies can dictate design capacities and failure modes makes this problem well suited for those who possess expertise in structural engineering. At the same time, a focus has been given to the performance metrics of materials at the nanoscale, including strength, toughness, and transport properties (e.g., electrical, thermal). Little effort has been made in the systematic characterization of system compatibility -- e.g., how to make disparate material building blocks behave in unison. This research attempts to develop bottom-up molecular scale understanding of material behavior, with the global objective being the application of this understanding into material design/characterization at an ultimate functional scale. In particular, it addresses the subject of cooperativity at the nano-scale. This research aims to define the conditions which dictate when discrete molecules may behave as a single, functional unit, thereby facilitating homogenization and up-scaling approaches, setting bounds for assembly, and providing a transferable assessment tool across molecular systems. Following a macro-scale pattern where the compatibility of deformation plays a vital role in the structural design, novel geometrical cooperativity metrics based on the gyration tensor are derived with the intention to define nano-cooperativity in a generalized way. The metrics objectively describe the general size, shape and orientation of the structure. To validate the derived measures, a pair of ideal macromolecules

  16. Fiscal 1999 survey report. Survey of feasibility of international cooperation in the transfer of technology; 1999 nendo gijutsu iten ni kakawaru kokusai kyoryoku kanosei chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Among the activity goals of CTI (climate technology initiative), which is a framework designed to encourage international cooperation of leading nations in the voluntary development and diffusion of technologies supposed to contribute to the reduction of greenhouse gas emissions, there is the promotion of the transfer and diffusion of climate change preventing technologies. To achieve the goal, energy efficiency oriented workshops will be held as part of the training for the raising of people skilled in energy saving, the results will be examined, the achievements attained at such events will be introduced at COP5 (Conference of the Parties at Bonn), and the responses of the respective countries will be reviewed, all these for the investigation of the feasibility of international cooperation for raising people dedicated to the reduction of greenhouse gas emission. In this fiscal year, aiming to make clear the possibility of contribution to the transfer of software-related technologies through cooperation of multiple nations, lecturers from leading countries and participants from developing nations met, held a workshop over energy efficiency technologies, and the results were compiled. (NEDO)

  17. Exploitative and hierarchical antagonism in a cooperative bacterium.

    Directory of Open Access Journals (Sweden)

    Francesca Fiegna

    2005-11-01

    Full Text Available Social organisms that cooperate with some members of their own species, such as close relatives, may fail to cooperate with other genotypes of the same species. Such noncooperation may take the form of outright antagonism or social exploitation. Myxococcus xanthus is a highly social prokaryote that cooperatively develops into spore-bearing, multicellular fruiting bodies in response to starvation. Here we have characterized the nature of social interactions among nine developmentally proficient strains of M. xanthus isolated from spatially distant locations. Strains were competed against one another in all possible pairwise combinations during starvation-induced development. In most pairings, at least one competitor exhibited strong antagonism toward its partner and a majority of mixes showed bidirectional antagonism that decreased total spore production, even to the point of driving whole populations to extinction. Differential response to mixing was the primary determinant of competitive superiority rather than the sporulation efficiencies of unmixed populations. In some competitive pairings, the dominant partner sporulated more efficiently in mixed populations than in clonal isolation. This finding represents a novel form of exploitation in bacteria carried out by socially competent genotypes and is the first documentation of social exploitation among natural bacterial isolates. Patterns of antagonistic superiority among these strains form a highly linear dominance hierarchy. At least some competition pairs construct chimeric, rather than segregated, fruiting bodies. The cooperative prokaryote M. xanthus has diverged into a large number of distinct social types that cooperate with clone-mates but exhibit intense antagonism toward distinct social types of the same species. Most lengthy migration events in nature may thus result in strong antagonism between migratory and resident populations, and this antagonism may have large effects on local

  18. Adult sex ratios and their implications for cooperative breeding in birds

    NARCIS (Netherlands)

    Komdeur, Jan; Székely, Tamás; Long, Xiaoyan; Kingma, Sjouke Anne

    2017-01-01

    Cooperative breeding is a form of breeding system where in addition to a core breeding pair, one or more usually non-breeding individuals provide offspring care. Cooperative breeding is widespread in birds, but its origin and maintenance in contemporary populations are debated. Although deviations

  19. Using Cooperative Learning To Improve Reading and Writing in Language Arts.

    Science.gov (United States)

    Bromley, Karen; Modlo, Marcia

    1997-01-01

    Deals with S. Kagan's (1990) structural approach to cooperative learning and its application to language arts. Offers detailed descriptions of several cooperative learning structures, including Numbered Heads Together, Roundtable, Think-Pair-Share, Corners, and others. Provides examples from actual classroom settings, along with various teacher…

  20. Test of s-wave pairing in heavy-fermion systems due to Kondo volume collapse

    International Nuclear Information System (INIS)

    Svozil, K.

    1987-01-01

    It is proposed to utilize resonant Raman scattering on heavy-fermion superconductors as a test for Cooper pairing via an effective phonon-mediated attraction due to the Kondo volume collapse. The suggested experiment might help to discriminate between singlet and triplet pairing

  1. Utility of Charge Transfer and Ion-Pair Complexation for Spectrophotometric Determination of Eletriptan Hydrobromide in Pure and Dosage Forms

    Directory of Open Access Journals (Sweden)

    Ayman A. Gouda

    2013-01-01

    Full Text Available Three simple, sensitive, and accurate spectrophotometric methods have been developed for the determination of eletriptan hydrobromide (ELT in pure and dosage forms. The first two methods are based on charge transfer complex formation between ELT and chromogenic reagents quinalizarin (Quinz and alizarin red S (ARS producing charge transfer complexes which showed an absorption maximum at 569 and 533 nm for Quinz and ARS, respectively. The third method is based on the formation of ion-pair complex between ELT with molybdenum(V-thiocyanate inorganic complex in hydrochloric acid medium followed by extraction of the colored ion-pair with dichloromethane and measured at 470 nm. Different variables affecting the reactions were studied and optimized. Beer's law is obeyed in the concentration ranges 2.0–18, 1.0–8.0, and 2.0–32 μg mL−1 for Quinz, ARS, and Mo(V-thiocyanate, respectively. The molar absorptivity, Sandell sensitivity, detection, and quantification limits are also calculated. The correlation coefficients were ≥0.9994 with a relative standard deviation (R.S.D%. of ≤0.925. The proposed methods were successfully applied for simultaneous determination of ELT in tablets with good accuracy and precision and without interferences from common additives, and the validity is assessed by applying the standard addition technique, which is compared with those obtained using the reported method.

  2. Coevolution of honest signaling and cooperative norms by cultural group selection.

    Science.gov (United States)

    Scheuring, István

    2010-08-01

    Evolution of cooperative norms is studied in a population where individual and group level selection are both in operation. Individuals play indirect reciprocity game within their group and follow second order norms. Individuals are norm-followers, and imitate their successful group mates. Aside from direct observation individuals can be informed about the previous actions and reputations by information transferred by others. A potential donor estimates the reputation of a potential receiver either by her own observation or by the opinion of the majority of others (indirect observation). Following a previous study (Scheuring, 2009) we assume that norms determine only the probabilities of actions, and mutants can differ in these probabilities. Similarly, we assume that individuals follow a stochastic information transfer strategy. The central question is whether cooperative norm and honest social information transfer can emerge in a population where initially only non-cooperative norms were present, and the transferred information was not sufficiently honest. It is shown that evolution can lead to a cooperative state where information transferred in a reliable manner, where generous cooperative strategies are dominant. This cooperative state emerges along a sharp transition of norms. We studied the characteristics of actions and strategies in this transition by classifying the stochastic norms, and found that a series of more and more judging strategies invade each other before the stabilization of the so-called generous judging strategy. Numerical experiments on the coevolution of social parameters (e.g. probability of direct observation and the number of indirect observers) reveal that it is advantageous to lean on indirect observation even if information transfer is much noisier than for direct observation, which is because to follow the majorities' opinion suppresses information noise meaningfully.

  3. Attribution models and the Cooperative Game Theory

    OpenAIRE

    Cano Berlanga, Sebastian; Vilella, Cori

    2017-01-01

    The current paper studies the attribution model used by Google Analytics. Precisely, we use the Cooperative Game Theory to propose a fair distribution of the revenues among the considered channels, in order to facilitate the cooperation and to guarantee stability. We define a transferable utility convex cooperative game from the observed frequencies and we use the Shapley value to allocate the revenues among the di erent channels. Furthermore, we evaluate the impact of an advertising...

  4. Multiconfiguration Pair-Density Functional Theory Outperforms Kohn-Sham Density Functional Theory and Multireference Perturbation Theory for Ground-State and Excited-State Charge Transfer.

    Science.gov (United States)

    Ghosh, Soumen; Sonnenberger, Andrew L; Hoyer, Chad E; Truhlar, Donald G; Gagliardi, Laura

    2015-08-11

    The correct description of charge transfer in ground and excited states is very important for molecular interactions, photochemistry, electrochemistry, and charge transport, but it is very challenging for Kohn-Sham (KS) density functional theory (DFT). KS-DFT exchange-correlation functionals without nonlocal exchange fail to describe both ground- and excited-state charge transfer properly. We have recently proposed a theory called multiconfiguration pair-density functional theory (MC-PDFT), which is based on a combination of multiconfiguration wave function theory with a new type of density functional called an on-top density functional. Here we have used MC-PDFT to study challenging ground- and excited-state charge-transfer processes by using on-top density functionals obtained by translating KS exchange-correlation functionals. For ground-state charge transfer, MC-PDFT performs better than either the PBE exchange-correlation functional or CASPT2 wave function theory. For excited-state charge transfer, MC-PDFT (unlike KS-DFT) shows qualitatively correct behavior at long-range with great improvement in predicted excitation energies.

  5. Thermodynamics of pairing phase transition in nuclei

    International Nuclear Information System (INIS)

    Karim, Afaque; Ahmad, Shakeb

    2014-01-01

    The pairing gaps, pairing energy, heat capacity and entropy are calculated within BCS (Bardeen- Cooper-Schrieffer) based quasi particle approach, including thermal fluctuations on pairing field within pairing model for all nuclei (light, medium, heavy and super heavy nuclei). Quasi particles approach in BCS theory was introduced and reformulated to study various properties. For thermodynamic behavior of nuclei at finite temperatures, the anomalous averages of creation and annihilation operators are introduced. It is solved self consistently at finite temperatures to obtain BCS Hamiltonian. After doing unitary transformation, we obtained the Hamiltonian in the diagonal form. Thus, one gets temperature dependence gap parameter and pairing energy for nuclei. Moreover, the energy at finite temperatures is the sum of the condensation energy and the thermal energy of fermionic quasi particles. With the help of BCS Hamiltonian, specific heat, entropy and free energy are calculated for different nuclei. In this paper the gap parameter occupation number and pairing energy as a function of temperature which is important for all the light, medium, heavy and super heavy nuclei is calculated. Moreover, the various thermo dynamical quantities like specific heat, entropy and free energy is also obtained for different nuclei. Thus, the thermodynamics of pairing phase transition in nuclei is studied

  6. Transfer of knowledge in international cooperation: the Farmanguinhos – SMM case

    Directory of Open Access Journals (Sweden)

    Samuel Araujo Gomes da Silva

    2017-11-01

    Full Text Available ABSTRACT OBJECTIVE To analyze the influence of four mechanisms of knowledge transfer (training, technical visits, expatriation, and standard operating procedures on the different dimensions (potential and realized of absorptive capacity in international technical cooperation. METHODS We examine the case of implementation of the Sociedade Moçambicana de Medicamentos. Data have been collected using semi-structured interviews (applied to 21 professionals of the Sociedade Moçambicana de Medicamentos, Farmanguinhos, FIOCRUZ, and Itamaraty and official documents. The data of the interviews have been submitted to content analysis, using the software NVivo. RESULTS Training and technical visits directly influenced the acquisition and, partly, the assimilation of knowledge. Expatriation contributed with the transformation of this knowledge from the development and refinement of operational routines. Finally, the definition of standard operating procedures allowed the Mozambican technicians to be the actors of the transformation of the knowledge previously acquired and assimilated and, at the same time, it laid the foundations for a future exploration of the knowledge. CONCLUSIONS Training and technical visits mainly influence the potential absorptive capacity, while expatriation and standard operating procedures most directly affect the realized absorptive capacity.

  7. Spin–orbit coupling, minimal model and potential Cooper-pairing from repulsion in BiS2-superconductors

    Science.gov (United States)

    Cobo-Lopez, Sergio; Saeed Bahramy, Mohammad; Arita, Ryotaro; Akbari, Alireza; Eremin, Ilya

    2018-04-01

    We develop the realistic minimal electronic model for recently discovered BiS2 superconductors including the spin–orbit (SO) coupling based on the first-principles band structure calculations. Due to strong SO coupling, characteristic for the Bi-based systems, the tight-binding low-energy model necessarily includes p x , p y , and p z orbitals. We analyze a potential Cooper-pairing instability from purely repulsive interaction for the moderate electronic correlations using the so-called leading angular harmonics approximation. For small and intermediate doping concentrations we find the dominant instabilities to be {d}{x2-{y}2}-wave, and s ±-wave symmetries, respectively. At the same time, in the absence of the sizable spin fluctuations the intra and interband Coulomb repulsions are of the same strength, which yield the strongly anisotropic behavior of the superconducting gaps on the Fermi surface. This agrees with recent angle resolved photoemission spectroscopy findings. In addition, we find that the Fermi surface topology for BiS2 layered systems at large electron doping can resemble the doped iron-based pnictide superconductors with electron and hole Fermi surfaces maintaining sufficient nesting between them. This could provide further boost to increase T c in these systems.

  8. Plasma blob generation due to cooperative elliptic instability.

    Science.gov (United States)

    Manz, P; Xu, M; Müller, S H; Fedorczak, N; Thakur, S C; Yu, J H; Tynan, G R

    2011-11-04

    Using fast-camera measurements the generation mechanism of plasma blobs is investigated in the linear device CSDX. During the ejection of plasma blobs the plasma is dominated by an m=1 mode, which is a counterrotating vortex pair. These flows are known to be subject to the cooperative elliptic instability, which is characterized by a cooperative disturbance of the vortex cores and results in a three-dimensional breakdown of two-dimensional flows. The first experimental evidence of a cooperative elliptic instability preceding the blob-ejection is provided in terms of the qualitative evolution of the vortex geometries and internal wave patterns.

  9. A comprehensive performance evaluation on the prediction results of existing cooperative transcription factors identification algorithms.

    Science.gov (United States)

    Lai, Fu-Jou; Chang, Hong-Tsun; Huang, Yueh-Min; Wu, Wei-Sheng

    2014-01-01

    Eukaryotic transcriptional regulation is known to be highly connected through the networks of cooperative transcription factors (TFs). Measuring the cooperativity of TFs is helpful for understanding the biological relevance of these TFs in regulating genes. The recent advances in computational techniques led to various predictions of cooperative TF pairs in yeast. As each algorithm integrated different data resources and was developed based on different rationales, it possessed its own merit and claimed outperforming others. However, the claim was prone to subjectivity because each algorithm compared with only a few other algorithms and only used a small set of performance indices for comparison. This motivated us to propose a series of indices to objectively evaluate the prediction performance of existing algorithms. And based on the proposed performance indices, we conducted a comprehensive performance evaluation. We collected 14 sets of predicted cooperative TF pairs (PCTFPs) in yeast from 14 existing algorithms in the literature. Using the eight performance indices we adopted/proposed, the cooperativity of each PCTFP was measured and a ranking score according to the mean cooperativity of the set was given to each set of PCTFPs under evaluation for each performance index. It was seen that the ranking scores of a set of PCTFPs vary with different performance indices, implying that an algorithm used in predicting cooperative TF pairs is of strength somewhere but may be of weakness elsewhere. We finally made a comprehensive ranking for these 14 sets. The results showed that Wang J's study obtained the best performance evaluation on the prediction of cooperative TF pairs in yeast. In this study, we adopted/proposed eight performance indices to make a comprehensive performance evaluation on the prediction results of 14 existing cooperative TFs identification algorithms. Most importantly, these proposed indices can be easily applied to measure the performance of new

  10. Charge transfer in DNA: role of base pairing

    Czech Academy of Sciences Publication Activity Database

    Kratochvílová, Irena; Bunček, M.; Schneider, Bohdan

    2009-01-01

    Roč. 38, Suppl. (2009), S123-S123 ISSN 0175-7571. [EBSA European Biophysics Congress /7./. Genoa, 11.07.2009-15.07.2009] Institutional research plan: CEZ:AV0Z10100520; CEZ:AV0Z50520701 Keywords : DNA * charge transport * base pairing Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.437, year: 2009

  11. Ex-vessel nuclear fuel transfer system

    International Nuclear Information System (INIS)

    Wade, E.E.

    1978-01-01

    A system for transferring fuel assemblies between a fuel transfer area and a fuel storage area while the fuel assemblies remain completely submerged in a continuous body of coolant is described. A fuel transfer area filled with reactor coolant communicating with the reactor vessel below the reactor coolant level provides a transfer area for fuel assemblies in transit to and from the reactor vessel. A positioning mechanism comprising at least one rotatable plug disposed on a fuel transfer tank located outside the reactor vessel cooperates with either the fuel transfer area or the fuel storage area to position a fuel assembly in transit. When in position, a transporting mechanism cooperating with the positioning mechanism lifts or lowers a chosen fuel assembly. The transporting mechanism together with the positioning mechanism are capable of transferring a fuel assembly between the fuel transfer area and the fuel storage area

  12. Enhancing Possible Sentence through Cooperative Learning (Open to Suggestion).

    Science.gov (United States)

    Jensen, Sharon J.; Duffelmeyer, Frederick A.

    1996-01-01

    Describes using Think-Pair-Share (a three-step cooperative learning activity) to complement the sentence-generation phase of the Possible Sentences Activity, a highly recommended prereading vocabulary strategy. (SR)

  13. Dependency links can hinder the evolution of cooperation in the prisoner's dilemma game on lattices and networks.

    Directory of Open Access Journals (Sweden)

    Xuwen Wang

    Full Text Available Networks with dependency links are more vulnerable when facing the attacks. Recent research also has demonstrated that the interdependent groups support the spreading of cooperation. We study the prisoner's dilemma games on spatial networks with dependency links, in which a fraction of individual pairs is selected to depend on each other. The dependency individuals can gain an extra payoff whose value is between the payoff of mutual cooperation and the value of temptation to defect. Thus, this mechanism reflects that the dependency relation is stronger than the relation of ordinary mutual cooperation, but it is not large enough to cause the defection of the dependency pair. We show that the dependence of individuals hinders, promotes and never affects the cooperation on regular ring networks, square lattice, random and scale-free networks, respectively. The results for the square lattice and regular ring networks are demonstrated by the pair approximation.

  14. Time-Resolved Magnetic Field Effects Distinguish Loose Ion Pairs from Exciplexes

    Science.gov (United States)

    2013-01-01

    We describe the experimental investigation of time-resolved magnetic field effects in exciplex-forming organic donor–acceptor systems. In these systems, the photoexcited acceptor state is predominantly deactivated by bimolecular electron transfer reactions (yielding radical ion pairs) or by direct exciplex formation. The delayed fluorescence emitted by the exciplex is magnetosensitive if the reaction pathway involves loose radical ion pair states. This magnetic field effect results from the coherent interconversion between the electronic singlet and triplet radical ion pair states as described by the radical pair mechanism. By monitoring the changes in the exciplex luminescence intensity when applying external magnetic fields, details of the reaction mechanism can be elucidated. In this work we present results obtained with the fluorophore-quencher pair 9,10-dimethylanthracene/N,N-dimethylaniline (DMA) in solvents of systematically varied permittivity. A simple theoretical model is introduced that allows discriminating the initial state of quenching, viz., the loose ion pair and the exciplex, based on the time-resolved magnetic field effect. The approach is validated by applying it to the isotopologous fluorophore-quencher pairs pyrene/DMA and pyrene-d10/DMA. We detect that both the exciplex and the radical ion pair are formed during the initial quenching stage. Upon increasing the solvent polarity, the relative importance of the distant electron transfer quenching increases. However, even in comparably polar media, the exciplex pathway remains remarkably significant. We discuss our results in relation to recent findings on the involvement of exciplexes in photoinduced electron transfer reactions. PMID:24041160

  15. Fuel transfer machine

    International Nuclear Information System (INIS)

    Bernstein, I.

    1978-01-01

    A nuclear fuel transfer machine for transferring fuel assemblies through the fuel transfer tube of a nuclear power generating plant containment structure is described. A conventional reversible drive cable is attached to the fuel transfer carriage to drive it horizontally through the tube. A shuttle carrying a sheave at each end is arranged in parallel with the carriage to also travel into the tube. The cable cooperating with the sheaves permit driving a relatively short fuel transfer carriage a large distance without manually installing sheaves or drive apparatus in the tunnel. 8 claims, 3 figures

  16. Does cooperation mean kinship between spatially discrete ant nests?

    Science.gov (United States)

    Procter, Duncan S; Cottrell, Joan E; Watts, Kevin; A'Hara, Stuart W; Hofreiter, Michael; Robinson, Elva J H

    2016-12-01

    Eusociality is one of the most complex forms of social organization, characterized by cooperative and reproductive units termed colonies. Altruistic behavior of workers within colonies is explained by inclusive fitness, with indirect fitness benefits accrued by helping kin. Members of a social insect colony are expected to be more closely related to one another than they are to other conspecifics. In many social insects, the colony can extend to multiple socially connected but spatially separate nests (polydomy). Social connections, such as trails between nests, promote cooperation and resource exchange, and we predict that workers from socially connected nests will have higher internest relatedness than those from socially unconnected, and noncooperating, nests. We measure social connections, resource exchange, and internest genetic relatedness in the polydomous wood ant Formica lugubris to test whether (1) socially connected but spatially separate nests cooperate, and (2) high internest relatedness is the underlying driver of this cooperation. Our results show that socially connected nests exhibit movement of workers and resources, which suggests they do cooperate, whereas unconnected nests do not. However, we find no difference in internest genetic relatedness between socially connected and unconnected nest pairs, both show high kinship. Our results suggest that neighboring pairs of connected nests show a social and cooperative distinction, but no genetic distinction. We hypothesize that the loss of a social connection may initiate ecological divergence within colonies. Genetic divergence between neighboring nests may build up only later, as a consequence rather than a cause of colony separation.

  17. Breaking of nucleon Cooper pairs at finite temperature in 93-98Mo

    International Nuclear Information System (INIS)

    Kaneko, K.; Hasegawa, M.; Agvaanluvsan, U.; Algin, E.; Chankova, R.; Guttormsen, M.; Larsen, A. C.; Rekstad, J.; Siem, S.; Mitchell, G. E.; Schiller, A.; Voinov, A.

    2006-01-01

    The S shape of the canonical heat-capacity curve is known as a signature of the pairing transition, and along an isotopic chain it is significantly more pronounced for nuclei with an even number of neutrons than for those with an odd number. Although the heat capacities extracted from experimental level densities in 93-98 Mo exhibit a clear S shape, they do not show such an odd-even staggering. To understand the underlying physics, we analyze thermal quantities evaluated from the partition function calculated using the static-path plus random-phase approximation (SPA+RPA) in a monopole pairing model with number-parity projection. The calculated level densities reproduce very well the experimental data, and they also agree with estimates made using the back-shifted Fermi-gas model. We clarify the reason why the heat capacities for Mo isotopes do not show odd-even staggering of the S shape. We also discuss thermal odd-even mass differences in 94-97 Mo that were calculated using the three-, four-, and five-point formulas. These thermal mass differences are regarded as indicators of pairing correlations at finite temperature

  18. 14 CFR 1274.931 - Electronic funds transfer payment methods.

    Science.gov (United States)

    2010-01-01

    ... cooperative agreement will be made by the Government by electronic funds transfer through the Treasury Fedline... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Electronic funds transfer payment methods... COOPERATIVE AGREEMENTS WITH COMMERCIAL FIRMS Other Provisions and Special Conditions § 1274.931 Electronic...

  19. Intense charge transfer surface based on graphene and thymine-Hg(II)-thymine base pairs for detection of Hg(2.).

    Science.gov (United States)

    Li, Jiao; Lu, Liping; Kang, Tianfang; Cheng, Shuiyuan

    2016-03-15

    In this article, we developed an electrochemiluminescence (ECL) sensor with a high-intensity charge transfer interface for Hg(2+) detection based on Hg(II)-induced DNA hybridization. The sensor was fabricated by the following simple method. First, graphene oxide (GO) was electrochemically reduced onto a glassy carbon electrode through cyclic voltammetry. Then, amino-labeled double-stranded (ds)DNA was assembled on the electrode surface using 1-pyrenebutyric acid N-hydroxysuccinimide as a linker between GO and DNA. The other terminal of dsDNA, which was labeled with biotin, was linked to CdSe quantum dots via biotin-avidin interactions. Reduced graphene oxide has excellent electrical conductivity. dsDNA with T-Hg(II)-T base pairs exhibited more facile charge transfer. They both accelerate the electron transfer performance and sensitivity of the sensor. The increased ECL signals were logarithmically linear with the concentration of Hg(II) when Hg(2+) was present in the detection solution. The linear range of the sensor was 10(-11) to 10(-8)mol/L (R=0.9819) with a detection limit of 10(-11)mol/L. This biosensor exhibited satisfactory results when it was used to detect Hg(II) in real water samples. The biosensor with high-intense charge transfer performance is a prospect avenue to pursue more and more sensitive detection method. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Building the Leviathan--Voluntary centralisation of punishment power sustains cooperation in humans.

    Science.gov (United States)

    Gross, Jörg; Méder, Zsombor Z; Okamoto-Barth, Sanae; Riedl, Arno

    2016-02-18

    The prevalence of cooperation among humans is puzzling because cooperators can be exploited by free riders. Peer punishment has been suggested as a solution to this puzzle, but cumulating evidence questions its robustness in sustaining cooperation. Amongst others, punishment fails when it is not powerful enough, or when it elicits counter-punishment. Existing research, however, has ignored that the distribution of punishment power can be the result of social interactions. We introduce a novel experiment in which individuals can transfer punishment power to others. We find that while decentralised peer punishment fails to overcome free riding, the voluntary transfer of punishment power enables groups to sustain cooperation. This is achieved by non-punishing cooperators empowering those who are willing to punish in the interest of the group. Our results show how voluntary power centralisation can efficiently sustain cooperation, which could explain why hierarchical power structures are widespread among animals and humans.

  1. Co-operatives as heating entrepreneurs

    International Nuclear Information System (INIS)

    Honkasalo, M.

    2000-01-01

    The objective of heating entrepreneurship functioning in the form of a co operative is to make the use of the wood chips competitive primarily through district heating of municipal centres. When compared with the conventional heating mode the reliability of chip delivery and the remuneration paid to the co-operative for attending to the running of the heating centres are considered to be the competitive advantages. The system has proven to be a working one; one indication of this is its growing application in the country. In the spring of the year 2000 there were 26 chip-based energy co-operative active in Finland. The first time that the use of bioenergy underwent a powerful rise was in the 1970s as a consequence of the oilcrises. Subsequently the enthusiasm shown to this energy form subsided. Then in the early 1990s, biofuels once again became a subject of interest mainly due to environmental issues, the restructuring of rural areas and silvicultural reasons. With the past decades' experiences forming the basis, the development needs associated with the use of bioenergy were in fresh memory and they were addressed on a wide font. Boiler technology related to solid fuels evolved rapidly and the least successful manufacturers had been eliminated by the recession. In the case of co-operative heating entrepreneurship, the commonest form neither the district heating centre nor the system of heat-transfer pipes belong to co-operative society. The co-operative is responsible only for the delivery of the fuel and for looking after the heating plant. Remuneration is generally based on the amount of energy leaving the district heating plant. Thus the heat dissipated at the heating plant is the co-operative's problem and the heat dissipated during transfer are the energy buyer's problem. The investor in the equipments usually the local municipality or an energy utility. In some cases the co-operative owns the equipments well, in which case it is correct to speak of

  2. Cooperative motion of intrinsic and actuated semiflexible swimmers

    NARCIS (Netherlands)

    Llopis, I.; Pagonabarraga, I.; Lagomarsino, M.C.; Lowe, C.P.

    2013-01-01

    We examine the phenomenon of hydrodynamic-induced cooperativity for pairs of flagellated micro-organism swimmers, of which spermatozoa cells are an example. We consider semiflexible swimmers, where inextensible filaments are driven by an internal intrinsic force and torque-free mechanism (intrinsic

  3. Measurements of differential cross-section ratios for single-nucleon transfer reaction pairs near A=25

    Energy Technology Data Exchange (ETDEWEB)

    Howard, A J; Moise, T S [Trinity Coll., Hartford, CT (USA). Dept. of Physics; Champagne, A E [Princeton Univ., NJ (USA). Dept. of Physics; Magnus, P V; Smith, M S [Yale Univ., New Haven, CT (USA). Wright Nuclear Structure Lab.

    1991-06-10

    Differential cross sections for the (d,p), ({sup 3}He,d), ({alpha},t) and ({alpha},{sup 3}He) reactions involving seventy-one residual states in {sup 23}Na, {sup 25}Mg, {sup 25}Al, and {sup 27}Al have been measured at a forward angle with incident energies of 17.5, 20.2, and 34.8 MeV, respectively. The ratio of cross-section pairs involving formation of the same residual state is determined for forty-five cases where both the angular momentum transfer and single-particle spectroscopic strength have been previously established. These are compared to values calculated with conventional distorted-wave Born approximation analysis, and the utility of this technique for identifying some levels which are possible s- or p-wave resonances is demonstrated and discussed for states in the vicinity of proton thresholds. An application is made involving proton threshold states in {sup 27}Al. (orig.).

  4. Costly advertising and the evolution of cooperation.

    Directory of Open Access Journals (Sweden)

    Markus Brede

    Full Text Available In this paper, I investigate the co-evolution of fast and slow strategy spread and game strategies in populations of spatially distributed agents engaged in a one off evolutionary dilemma game. Agents are characterized by a pair of traits, a game strategy (cooperate or defect and a binary 'advertising' strategy (advertise or don't advertise. Advertising, which comes at a cost [Formula: see text], allows investment into faster propagation of the agents' traits to adjacent individuals. Importantly, game strategy and advertising strategy are subject to the same evolutionary mechanism. Via analytical reasoning and numerical simulations I demonstrate that a range of advertising costs exists, such that the prevalence of cooperation is significantly enhanced through co-evolution. Linking costly replication to the success of cooperators exposes a novel co-evolutionary mechanism that might contribute towards a better understanding of the origins of cooperation-supporting heterogeneity in agent populations.

  5. Costly advertising and the evolution of cooperation.

    Science.gov (United States)

    Brede, Markus

    2013-01-01

    In this paper, I investigate the co-evolution of fast and slow strategy spread and game strategies in populations of spatially distributed agents engaged in a one off evolutionary dilemma game. Agents are characterized by a pair of traits, a game strategy (cooperate or defect) and a binary 'advertising' strategy (advertise or don't advertise). Advertising, which comes at a cost [Formula: see text], allows investment into faster propagation of the agents' traits to adjacent individuals. Importantly, game strategy and advertising strategy are subject to the same evolutionary mechanism. Via analytical reasoning and numerical simulations I demonstrate that a range of advertising costs exists, such that the prevalence of cooperation is significantly enhanced through co-evolution. Linking costly replication to the success of cooperators exposes a novel co-evolutionary mechanism that might contribute towards a better understanding of the origins of cooperation-supporting heterogeneity in agent populations.

  6. Costly Advertising and the Evolution of Cooperation

    Science.gov (United States)

    Brede, Markus

    2013-01-01

    In this paper, I investigate the co-evolution of fast and slow strategy spread and game strategies in populations of spatially distributed agents engaged in a one off evolutionary dilemma game. Agents are characterized by a pair of traits, a game strategy (cooperate or defect) and a binary ‘advertising’ strategy (advertise or don’t advertise). Advertising, which comes at a cost , allows investment into faster propagation of the agents’ traits to adjacent individuals. Importantly, game strategy and advertising strategy are subject to the same evolutionary mechanism. Via analytical reasoning and numerical simulations I demonstrate that a range of advertising costs exists, such that the prevalence of cooperation is significantly enhanced through co-evolution. Linking costly replication to the success of cooperators exposes a novel co-evolutionary mechanism that might contribute towards a better understanding of the origins of cooperation-supporting heterogeneity in agent populations. PMID:23861752

  7. Virtual MIMO Beamforming and Device Pairing Enabled by Device-to-Device Communications for Multidevice Networks

    Directory of Open Access Journals (Sweden)

    Yeonjin Jeong

    2017-01-01

    Full Text Available We consider a multidevice network with asymmetric antenna configurations which supports not only communications between an access point and devices but also device-to-device (D2D communications for the Internet of things. For the network, we propose the transmit and receive beamforming with the channel state information (CSI for virtual multiple-input multiple-output (MIMO enabled by D2D receive cooperation. We analyze the sum rate achieved by a device pair in the proposed method and identify the strategies to improve the sum rate of the device pair. We next present a distributed algorithm and its equivalent algorithm for device pairing to maximize the throughput of the multidevice network. Simulation results confirm the advantages of the transmit CSI and D2D cooperation as well as the validity of the distributive algorithm.

  8. Fifty years of Technical Cooperation

    International Nuclear Information System (INIS)

    2007-01-01

    The International Atomic Energy Agency (IAEA) was established in Vienna in 1957. The Statute of the IAEA, approved by 81 nations, founded the organization on three pillars: nuclear verification; safety and security; and the transfer of technology. Today, these three pillars still remain at the heart of the organization's work. However, the way in which the IAEA carries out this work, particularly with regard to technology transfer, has changed greatly over the years. When the IAEA opened for business, nuclear science and technology were in their infancy. Many Member States had no nuclear capacity at all. The IAEA's 'technical assistance' programme, as it was then known, was modest. Early projects were small in scale and short lived, focusing mainly on building human capacities and creating institutions and facilities that would support the introduction of nuclear technology in a safe and effective manner. Today, the picture is more complex. Instead of merely offering assistance, the IAEA focuses on cooperation for sustainable socioeconomic development, building on the skills and infrastructure that Member States have acquired over the past five decades. Member States are full partners in the process, guiding the IAEA's technical cooperation activities, setting national and regional priorities, and offering training opportunities and technical support to the IAEA and to other Member States. Technical cooperation between developing countries is facilitated and supported through regional cooperative agreements. Regional centres of expertise play an important role in sharing the benefits of nuclear science and technology among Member States

  9. China-Africa: New Directions of Cooperation

    Directory of Open Access Journals (Sweden)

    L V Ponomarenko

    2015-12-01

    Full Text Available This article analyzes the policy of fifth generation of Chinese leadership with regard to African states. The article deals with the concept of “Chinese Dream”, which was first declared in Africa, an innovative model of international cooperation in the framework of the formation of “economic zone of the Silk Road”. The authors reveal three basic directions of cooperation - political, economic and humanitarian cooperation. Political cooperation is characterized by the activation of mutual visits at the highest level, the interaction in the framework of the UN General Assembly, participation in UN peacekeeping operations. Economic cooperation is characterized by the activation of bilateral trade, the transition to a “modernized version of” investment cooperation, implementation of the strategy of “going abroad” of Chinese products, imports of natural resources from Africa, creating jobs for the local population, financing of infrastructure projects, the transfer of labor-intensive industries in Africa. Humanitarian cooperation includes training program for Africa, the implementation of the Sino-African programs, technology partnerships, research and exchange, and the China-Africa Forum “Think Tank”. Cooperation in health care also plays an important role. The authors note that the new Chinese leadership declares transition to an upgraded version of the Sino-African cooperation.

  10. The increased risk of predation enhances cooperation

    Science.gov (United States)

    Krams, Indrikis; Bērziņš, Arnis; Krama, Tatjana; Wheatcroft, David; Igaune, Kristīne; Rantala, Markus J.

    2010-01-01

    Theory predicts that animals in adverse conditions can decrease individual risks and increase long-term benefits by cooperating with neighbours. However, some empirical studies suggest that animals often focus on short-term benefits, which can reduce the likelihood that they will cooperate with others. In this experimental study, we tested between these two alternatives by evaluating whether increased predation risk (as a correlate of environmental adversity) enhances or diminishes the occurrence of cooperation in mobbing, a common anti-predator behaviour, among breeding pied flycatchers Ficedula hypoleuca. We tested whether birds would join their mobbing neighbours more often and harass a stuffed predator placed near their neighbours' nests more intensely in areas with a higher perceived risk of predation. Our results show that birds attended mobs initiated by their neighbours more often, approached the stuffed predator significantly more closely, and mobbed it at a higher intensity in areas where the perceived risk of predation was experimentally increased. In such high-risk areas, birds also were more often involved in between-pair cooperation. This study demonstrates the positive impact of predation risk on cooperation in breeding songbirds, which might help in explaining the emergence and evolution of cooperation. PMID:19846454

  11. Nucleon transfer between heavy nuclei

    International Nuclear Information System (INIS)

    Von Oertzen, W.

    1984-02-01

    Nucleon transfer reactions between heavy nuclei are characterized by the classical behaviour of the scattering orbits. Thus semiclassical concepts are well suited for the description of these reactions. In the present contribution the characteristics of single and multinucleon transfer reactions at energies below and above the Coulomb barrier are shown for systems like Sn+Sn, Xe+U and Ni+Pb. The role of the pairing interaction in the transfer of nucleon pairs is illustrated. For strong transitions the coupling of channels and the absorption into more complicated channels is taken into account in a coupled channels calculation

  12. Pair correlations in near-magic nuclei and the nucleon--phonon interaction

    International Nuclear Information System (INIS)

    Kadmenskii, S.G.; Luk'yanovich, P.A.; Remesov, Y.I.; Furman, V.I.

    1987-01-01

    It is demonstrated that the nucleon-pairing phenomenon is entirely due to the finiteness of nuclei. A technique for taking account of the phonon-exchange-related retarded interaction in the particle--particle channel is developed for nuclei of the ''mag +- 2'' and ''mag +- 3'' types. It is shown that the nucleon--phonon interaction strength computed with allowance for the most collectivized surface oscillation branches makes it possible to ensure the correct attraction scale necessary for the description of the pairing phenomenon. The existence of a more profound similarity between the phenomena of superconductivity of metals and Cooper pairing of nucleons in nuclei is thus demonstrated

  13. Formation of Singlet Fermion Pairs in the Dilute Gas of Boson-Fermion Mixture

    Directory of Open Access Journals (Sweden)

    Minasyan V.

    2010-10-01

    Full Text Available We argue the formation of a free neutron spinless pairs in a liquid helium -dilute neutron gas mixture. We show that the term, of the interaction between the excitations of the Bose gas and the density modes of the neutron, meditate an attractive interaction via the neutron modes, which in turn leads to a bound state on a spinless neutron pair. Due to presented theoretical approach, we prove that the electron pairs in superconductivity could be discovered by Frölich earlier then it was made by the Cooper.

  14. Cooperation under indirect reciprocity and imitative trust.

    Science.gov (United States)

    Saavedra, Serguei; Smith, David; Reed-Tsochas, Felix

    2010-10-27

    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.

  15. 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.

  16. Agreement between the government of Australia and the government of the Republic of Korea concerning cooperation in peaceful uses of nuclear energy and the transfer of nuclear material

    International Nuclear Information System (INIS)

    1979-01-01

    The agreement contains fourteen articles under which the parties will cooperate in the peaceful uses of nuclear energy, including transfer of nuclear materials, research and development, exchange of unclassified information, technical training, visits by scientists and projects of mutual interest

  17. Cooperation makes two less-creative individuals turn into a highly-creative pair.

    Science.gov (United States)

    Xue, Hua; Lu, Kelong; Hao, Ning

    2018-05-15

    This study aimed to investigate which type of group (e.g., consisting of less-creative or highly-creative individuals) would perform better in solving creativity problems, and explore the underlying inter-brain neural correlates between team members. A preliminary test (an alternative-uses task) was performed to rank individuals' level of creativity, and divide participants into three types of dyads: high-high (two highly-creative individuals), low-low (two less-creative individuals), and high-low (one highly-creative and one less-creative individual). Dyads were then asked to solve a realistic presented problem (RPP; a typical creativity problem) during which a functional near-infrared spectroscopy (fNIRS)-based hyperscanning device was used to record the variation of interpersonal brain synchronization (IBS). Results revealed that less-creative individuals, while working together, would perform as well as highly-creative individuals. The low-low dyads showed higher levels of cooperation behaviour than the other two types of dyads. The fNIRS results revealed increased IBS only for low-low dyads at PFC (prefrontal cortex) and rTPJ (right temporal-parietal junction) brain regions during RPP task performance. In the rDLPFC (right dorsolateral prefrontal cortex), the IBS in the low-low dyads was stronger than that of high-high and high-low dyads. In the rTPJ, the IBS in the low-low dyads was only stronger than that of the high-low dyads. Besides, the IBS at rDLPFC and rTPJ regions in the low-low dyads was positively correlated with their cooperation behaviour and group creative performance. These findings indicated when two less-creative individuals worked on a creativity problem together, they tended to cooperate with each other (indicated by both behaviour index and increased IBS at rDLPFC and rTPJ), which benefited their creative performance. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Compromise in cooperative game and the VIKOR method

    Directory of Open Access Journals (Sweden)

    Opricović Serafim

    2009-01-01

    Full Text Available Five approaches in conflict resolution are distinguished, based on cooperativeness and aggressiveness in resolving conflict. Compromise based on cooperativeness is emphasized here as a solution in conflict resolution. Cooperative game theory oriented towards aiding the conflict resolution is considered and the compromise value for TU(transferable utility-game is presented. The method VIKOR could be applied to determine compromise solution of a multicriteria decision making problem with noncommensurable and conflicting criteria. Compromise is considered as an intermediate state between conflicting objectives or criteria reached by mutual concession. The applicability of the cooperative game theory and the VIKOR method for conflict resolution is illustrated.

  19. Fis protein induced λF-DNA bending observed by single-pair fluorescence resonance energy transfer

    Science.gov (United States)

    Chi-Cheng, Fu; Wunshain, Fann; Yuan Hanna, S.

    2006-03-01

    Fis, a site-specific DNA binding protein, regulates many biological processes including recombination, transcription, and replication in E.coli. Fis induced DNA bending plays an important role in regulating these functions and bending angle range from ˜50 to 95 dependent on the DNA sequence. For instance, the average bending angle of λF-DNA (26 bp, 8.8nm long, contained λF binding site on the center) measured by gel mobility shift assays was ˜ 94 . But the traditional method cannot provide information about the dynamics and the angle distribution. In this study, λF-DNA was labeled with donor (Alexa Fluor 546) and acceptor (Alexa Fluor 647) dyes on its two 5' ends and the donor-acceptor distances were measured using single-pair fluorescence resonance energy transfer (sp-FRET) with and without the present of Fis protein. Combing with structure information of Fis-DNA complex, the sp-FRET results are used to estimate the protein induced DNA bending angle distribution and dynamics.

  20. Crossover from BCS to composite boson (local pair) superconductivity in quasi-2D systems

    International Nuclear Information System (INIS)

    Gorbar, E.V.; Loktev, V.M.; Sharapov, S.G.

    1995-01-01

    The crossover from cooperative Cooper pairing to independent bound state (composite bosons) formation and condensation in quasi-2 D systems is studied. It is shown that at low carrier density the critical superconducting temperature is equal to the temperature of Bose-condensation of ideal quasi-2 D Bose-gas with heavy dynamical mass, meanwhile at high densities the BCS result remains valid. 15 refs

  1. Observation of aggregation triggered by Resonance Energy Transfer (RET) induced intermolecular pairing force.

    Science.gov (United States)

    Pan, Xiaoyong; Wang, Weizhi; Ke, Lin; Zhang, Nan

    2017-07-20

    In this report, we showed the existence of RET induced intermolecular pairing force by comparing their fluorescence behaviors under room illumination vs standing in dark area for either PFluAnt solution or PFluAnt&PFOBT mixture. Their prominent emission attenuation under room illumination brought out the critical role of photo, i.e. RET induced intermolecular pairing force in induction of polymer aggregation. Constant UV-Vis absorption and fluorescence spectra in terms of both peak shapes and maximum wavelengths implied no chemical decomposition was involved. Recoverable fluorescence intensity, fluorescence lifetime as well as NMR spectra further exclude photo induced decomposition. The controllable on/off state of RET induced intermolecular pairing force was verified by the masking effect of outside PFluAnt solution which function as filter to block the excitation of inside PFluAnt and thus off the RET induced intermolecular pairing force. Theoretical calculation suggest that magnitude of RET induced intermolecular pairing force is on the same scale as that of van der Waals interaction. Although the absolute magnitude of RET induced intermolecular pairing force was not tunable, its effect can be magnified by intentionally turn it "on", which was achieved by irradiance with 5 W desk lamp in this report.

  2. Innovative technology transfer of nondestructive evaluation research

    Science.gov (United States)

    Brian Brashaw; Robert J. Ross; Xiping Wang

    2008-01-01

    Technology transfer is often an afterthought for many nondestructive evaluation (NDE) researchers. Effective technology transfer should be considered during the planning and execution of research projects. This paper outlines strategies for using technology transfer in NDE research and presents a wide variety of technology transfer methods used by a cooperative...

  3. Metal-mediated DNA base pairing: alternatives to hydrogen-bonded Watson-Crick base pairs.

    Science.gov (United States)

    Takezawa, Yusuke; Shionoya, Mitsuhiko

    2012-12-18

    With its capacity to store and transfer the genetic information within a sequence of monomers, DNA forms its central role in chemical evolution through replication and amplification. This elegant behavior is largely based on highly specific molecular recognition between nucleobases through the specific hydrogen bonds in the Watson-Crick base pairing system. While the native base pairs have been amazingly sophisticated through the long history of evolution, synthetic chemists have devoted considerable efforts to create alternative base pairing systems in recent decades. Most of these new systems were designed based on the shape complementarity of the pairs or the rearrangement of hydrogen-bonding patterns. We wondered whether metal coordination could serve as an alternative driving force for DNA base pairing and why hydrogen bonding was selected on Earth in the course of molecular evolution. Therefore, we envisioned an alternative design strategy: we replaced hydrogen bonding with another important scheme in biological systems, metal-coordination bonding. In this Account, we provide an overview of the chemistry of metal-mediated base pairing including basic concepts, molecular design, characteristic structures and properties, and possible applications of DNA-based molecular systems. We describe several examples of artificial metal-mediated base pairs, such as Cu(2+)-mediated hydroxypyridone base pair, H-Cu(2+)-H (where H denotes a hydroxypyridone-bearing nucleoside), developed by us and other researchers. To design the metallo-base pairs we carefully chose appropriate combinations of ligand-bearing nucleosides and metal ions. As expected from their stronger bonding through metal coordination, DNA duplexes possessing metallo-base pairs exhibited higher thermal stability than natural hydrogen-bonded DNAs. Furthermore, we could also use metal-mediated base pairs to construct or induce other high-order structures. These features could lead to metal-responsive functional

  4. Existence and consequences of Coulomb pairing of electrons in a solid

    International Nuclear Information System (INIS)

    Mahajan, S.M.; Thyagaraja, A.

    1996-11-01

    It is shown from first principles that, in the periodic potential of a crystalline solid, short-range (i.e., screened) binary Coulomb interactions can lead to a two-electron bound state. It is further suggested that these composite bosonic states (charge -2e, and typically spin zero) could mediate an effectively attractive interaction between pairs of conduction electrons close to the Fermi level. This necessarily short range attractive interaction, which is crucially dependent on the band structure of the solid, and is complementary to the phonon-mediated one, may provide a source for the existence and properties of short correlation-length electron pairs (analogous to but distinct from Cooper pairs) needed to understand high temperature superconductivity. Several distinctive and observable characteristics of the proposed pairing scheme are discussed

  5. The broken-pair model for nuclei and its extension with quadrupole vibrations

    International Nuclear Information System (INIS)

    Hofstra, P.

    1979-01-01

    The author presents calculations for low energy properties of nuclei with an odd number of particles. These are described in the Broken-Pair approximation, where it is assumed that all but three particles occur as ordered Cooper pairs; the unpaired (one or three) particles are called quasiparticles. A model is developed with which it is hoped to describe odd nuclei with two open shells in terms of both single-particle and collective degrees of freedom. (Auth.)

  6. Building the Leviathan – Voluntary centralisation of punishment power sustains cooperation in humans

    Science.gov (United States)

    Gross, Jörg; Méder, Zsombor Z.; Okamoto-Barth, Sanae; Riedl, Arno

    2016-01-01

    The prevalence of cooperation among humans is puzzling because cooperators can be exploited by free riders. Peer punishment has been suggested as a solution to this puzzle, but cumulating evidence questions its robustness in sustaining cooperation. Amongst others, punishment fails when it is not powerful enough, or when it elicits counter-punishment. Existing research, however, has ignored that the distribution of punishment power can be the result of social interactions. We introduce a novel experiment in which individuals can transfer punishment power to others. We find that while decentralised peer punishment fails to overcome free riding, the voluntary transfer of punishment power enables groups to sustain cooperation. This is achieved by non-punishing cooperators empowering those who are willing to punish in the interest of the group. Our results show how voluntary power centralisation can efficiently sustain cooperation, which could explain why hierarchical power structures are widespread among animals and humans. PMID:26888519

  7. Design options for cooperation mechanisms under the new European renewable energy directive

    International Nuclear Information System (INIS)

    Klessmann, Corinna; Lamers, Patrick; Ragwitz, Mario; Resch, Gustav

    2010-01-01

    In June 2009, a new EU directive on the promotion of renewable energy sources (RES) entered into effect. The directive 2009/28/EC, provides for three cooperation mechanisms that will allow member states to achieve their national RES target in cooperation with other member states: statistical transfer, joint projects, and joint support schemes. This article analyses the pros and cons of the three mechanisms and explores design options for their implementation through strategic and economic questions: How to counterbalance the major drawbacks of each mechanism? How to reflect a balance of costs and benefits between the involved member states? The analysis identifies a number of design options that respond to these questions, e.g. long term contracts to ensure sufficient flexibility for statistical transfers, a coordinated, standardised joint project approach to increase transparency in the European market, and a stepwise harmonisation of joint support schemes that is based on a cost-effective accounting approach. One conclusion is that the three cooperation mechanisms are closely interlinked. One can consider their relation to be a gradual transition from member state cooperation under fully closed national support systems in case of statistical transfers, to cooperation under fully open national support systems in a joint support scheme.

  8. The International Stripa Project: Technology transfer from cooperation in scientific and technological research on nuclear waste disposal

    International Nuclear Information System (INIS)

    Levich, R.A.; Ferrigan, P.M.; Wilkey, P.L.

    1990-01-01

    The Nuclear Energy Agency of the organization for Economic Cooperation and Development (OECD/NEA) sponsors the International Stripa Project. The objectives of the Stripa Project are to develop techniques for characterizing sites located deep in rock formations that are potentially suitable for the geologic disposal of high-level radioactive wastes and to evaluate particular engineering design considerations that could enhance the long-term safety of a high-level radioactive waste repository in a geologic medium. The purpose of this paper is to briefly summarize the research conducted at Stripa and discuss the ways in which the technology developed for the Stripa Project has been and will be transfered to the United States Civilian Radioactive Waste Management Program's Yucca Mountain Project. 3 refs., 2 figs

  9. Concealed d-wave pairs in the s± condensate of iron-based superconductors.

    Science.gov (United States)

    Ong, Tzen; Coleman, Piers; Schmalian, Jörg

    2016-05-17

    A central question in iron-based superconductivity is the mechanism by which the paired electrons minimize their strong mutual Coulomb repulsion. In most unconventional superconductors, Coulomb repulsion is minimized through the formation of higher angular momentum Cooper pairs, with Fermi surface nodes in the pair wavefunction. The apparent absence of such nodes in the iron-based superconductors has led to a belief they form an s-wave ([Formula: see text]) singlet state, which changes sign between the electron and hole pockets. However, the multiorbital nature of these systems opens an alternative possibility. Here, we propose a new class of [Formula: see text] state containing a condensate of d-wave Cooper pairs, concealed by their entanglement with the iron orbitals. By combining the d-wave ([Formula: see text]) motion of the pairs with the internal angular momenta [Formula: see text] of the iron orbitals to make a singlet ([Formula: see text]), an [Formula: see text] superconductor with a nontrivial topology is formed. This scenario allows us to understand the development of octet nodes in potassium-doped Ba1-x KXFe2As2 as a reconfiguration of the orbital and internal angular momentum into a high spin ([Formula: see text]) state; the reverse transition under pressure into a fully gapped state can then be interpreted as a return to the low-spin singlet. The formation of orbitally entangled pairs is predicted to give rise to a shift in the orbital content at the Fermi surface, which can be tested via laser-based angle-resolved photoemission spectroscopy.

  10. Cooper-pair and Bose-Einstein condensations in two dimensions: A critical analysis based on the Nozieres and Schmitt-Rink formalism

    International Nuclear Information System (INIS)

    Tokumitu, A.; Miyake, K.; Yamada, K.

    1993-01-01

    The crossover between the Cooper-pair condensation and the Bose-Einstein condensation of ''di-electronic'' molecules in two-dimensional superconductors is investigated in detail on the basis of the Nozieres and Schmitt-Rink formalism. It is shown that temperature dependence of the chemical potential μ so calculated is classified into two classes as decreasing temperatures; i.e., class (a) where μ approaches the point of Bose-Einstein condensation of two-dimensional ideal Bose gas of ''di-electronic'' molecules, and class (b) where μ diverges positively along the line of BCS-type mean-field pair condensation. This feature is rather universal irrespective of strength V of the attractive interaction of the s-wave type. While the former class (a) has been found by Schmitt-Rink, Varma, and Ruckenstein, existence of the latter class (b) is recognized here. In the case where V is fixed, class (a) is realized for electron number density N smaller than N cr , which is an increasing function of V, and class (b) is realized for N larger than N cr . If N much-gt N cr in particular, there exists a regime, where the Fermi-liquid-like description is valid, between the BCS-type mean-field transition temperature and the Fermi temperature. In the situation where V is changed with N being fixed, low-temperature states for the strong-coupling case belong to class (a) while those for the weak-coupling case belong to class (b). Therefore, with decreasing V, the chemical potential μ(T), at temperatures far below the Fermi temperature, shows a discontinuous jump at V=V cr (N) corresponding to the transition from class (a) to (b)

  11. Cooperation between epithelial cells demonstrated by potassium transfer

    International Nuclear Information System (INIS)

    Ledbetter, M.L.; Young, G.J.; Wright, E.R.

    1986-01-01

    Junction-mediated communication can be measured in fibroblast cultures by determining the ability of mixed cultures of cells sensitive and resistant to ouabain to concentrate K+ in the presence of ouabain. We now report the extension of this assay procedure to cultured epithelial cells. Hamster kidney (HaK) cells maintain their ability to concentrate K+ in ouabain at levels inhibitory to dog kidney (MDCK) cells. When HaK and MDCK cells were cultured together in ouabain-containing medium, the K+ (measured as 86Rb+) in the mixed population was greater than expected if the cells were not interacting. The degree of enhancement, expressed as index of cooperation, depended on the numbers of cells in the cultures, their opportunity for cell-to-cell contact, and (above a certain permissive level) the concentration of ouabain. As with other cell types, protein synthesis in MDCK cells depends on maintenance of cell K+. Autoradiography of cells incubated with [3H]leucine demonstrated that MDCK cells in ouabain-treated mixed cultures were able to synthesize proteins only when physically adjacent to HaK cells. The transmission of labeled nucleosides among the cells provides independent evidence of the phenomenon of cooperation, probably mediated by gap junctions. This system offers promise for investigation of stimuli modulating junctional communication

  12. Hybridized plasmon in an asymmetric cut-wire-pair structure

    Energy Technology Data Exchange (ETDEWEB)

    Tung, Nguyen Thanh [Vietnamese Military Academy of Science and Technology, Hanoi (Viet Nam); Hanyang University, Seoul (Korea, Republic of); Rhee, Joo Yull [Sungkyunkwan University, Suwon (Korea, Republic of); Park, Jin Woo; Lee, Young Pak [Hanyang University, Seoul (Korea, Republic of)

    2010-12-15

    In this report, we discuss an electromagnetic analog of the molecular-orbital theory for metamaterial structures. We show that the electromagnetic responses of a metamagnetic structure consisting of paired cut-wires can be well understood by using the plasmon-hybridization mechanism. The simulated transmission spectra of the asymmetric cut-wire-pair structure, which were obtained utilizing the transfer-matrix method, strongly support our suggestion.

  13. Effect of proton transfer on the electronic coupling in DNA

    International Nuclear Information System (INIS)

    Rak, Janusz; Makowska, Joanna; Voityuk, Alexander A.

    2006-01-01

    The effects of single and double proton transfer within Watson-Crick base pairs on donor-acceptor electronic couplings, V da , in DNA are studied on the bases of quantum chemical calculations. Four dimers [AT,AT], [GC,GC], [GC,AT] and [GC,TA)] are considered. Three techniques - the generalized Mulliken-Hush scheme, the fragment charge method and the diabatic states method - are employed to estimate V da for hole transfer between base pairs. We show that both single- and double proton transfer (PT) reactions may substantially affect the electronic coupling in DNA. The electronic coupling in [AT,AT] is predicted to be most sensitive to PT. Single PT within the first base pair in the dimer leads to increase in the hole transfer efficiency by a factor of 4, while proton transfer within the second pair should substantially, by 2.7 times, decrease the rate of charge transfer. Thus, directional asymmetry of the PT effects on the electronic coupling is predicted. The changes in the V da matrix elements correlate with the topological properties of orbitals of donor and acceptor and can be qualitatively rationalized in terms of resonance structures of donor and acceptor. Atomic pair contributions to the V da matrix elements are also analyzed

  14. Pairing versus phase coherence of doped holes in distinct quantum spin backgrounds

    Science.gov (United States)

    Zhu, Zheng; Sheng, D. N.; Weng, Zheng-Yu

    2018-03-01

    We examine the pairing structure of holes injected into two distinct spin backgrounds: a short-range antiferromagnetic phase versus a symmetry protected topological phase. Based on density matrix renormalization group (DMRG) simulation, we find that although there is a strong binding between two holes in both phases, phase fluctuations can significantly influence the pair-pair correlation depending on the spin-spin correlation in the background. Here the phase fluctuation is identified as an intrinsic string operator nonlocally controlled by the spins. We show that while the pairing amplitude is generally large, the coherent Cooper pairing can be substantially weakened by the phase fluctuation in the symmetry-protected topological phase, in contrast to the short-range antiferromagnetic phase. It provides an example of a non-BCS mechanism for pairing, in which the paring phase coherence is determined by the underlying spin state self-consistently, bearing an interesting resemblance to the pseudogap physics in the cuprate.

  15. The need analysis of chemistry module based on REACT (relating, experiencing, applying, cooperating and transferring) to improve critical thinking ability

    Science.gov (United States)

    Tyffani, D. M.; Utomo, S. B.; Rahardjo, S. B.

    2018-05-01

    This research was aimed to find out how students’ need of chemistry module based REACT (Relating, Experiencing, Applying, Cooperating and Transferring) to improve students’ critical thinking ability. The subjects of this research was the studentsof XI grade in three school in even semester of academic year 2016-2017 that contained of 48 students of Senior High School 2 Bandar Lampung, 38 students of Senior High School 3 Bandar Lampung and 46 students of Senior High School 12 Bandar Lampung. The data was gathering used non-test method by using open questionnaire with 13 questions. The results showed that 84,84% of students stated that the development of chemistry module based REACT on colloid material is needed. The analysis of hand’s book was used aspects of critical thinking proposed by Facione (2011) are interpretation, analysis, evaluation, conclusion, and explanation. Based on the result of the analysis of hand’s book at Senior High School 12 Bandar Lampung for critical thinking in colloid material that indicate 50% indicator is appropriate, while for indicator of inference and explanation only 16,67% appropriate, then for indicator analysis and evaluation doesn’t have conformity. Based on the results of the analysis shows that the hand’s book used have not empowered critical thinking ability with maximum. The development of chemistry module on colloid material is needed to overcome the problem of hand’s book that hasn’t maximized critical thinking ability, then the development of module oriented to REACT learning model (Relating, Experiencing, Applying, Cooperating, and Transferring).

  16. Computational Aspects of Cooperative Game Theory

    CERN Document Server

    Chalkiadakis, Georgios; Wooldridge, Michael

    2011-01-01

    Cooperative game theory is a branch of (micro-)economics that studies the behavior of self-interested agents in strategic settings where binding agreements among agents are possible. Our aim in this book is to present a survey of work on the computational aspects of cooperative game theory. We begin by formally defining transferable utility games in characteristic function form, and introducing key solution concepts such as the core and the Shapley value. We then discuss two major issues that arise when considering such games from a computational perspective: identifying compact representation

  17. HAL-2 promotes homologous pairing during Caenorhabditis elegans meiosis by antagonizing inhibitory effects of synaptonemal complex precursors.

    Science.gov (United States)

    Zhang, Weibin; Miley, Natasha; Zastrow, Michael S; MacQueen, Amy J; Sato, Aya; Nabeshima, Kentaro; Martinez-Perez, Enrique; Mlynarczyk-Evans, Susanna; Carlton, Peter M; Villeneuve, Anne M

    2012-01-01

    During meiosis, chromosomes align with their homologous pairing partners and stabilize this alignment through assembly of the synaptonemal complex (SC). Since the SC assembles cooperatively yet is indifferent to homology, pairing and SC assembly must be tightly coordinated. We identify HAL-2 as a key mediator in this coordination, showing that HAL-2 promotes pairing largely by preventing detrimental effects of SC precursors (SYP proteins). hal-2 mutants fail to establish pairing and lack multiple markers of chromosome movement mediated by pairing centers (PCs), chromosome sites that link chromosomes to cytoplasmic microtubules through nuclear envelope-spanning complexes. Moreover, SYP proteins load inappropriately along individual unpaired chromosomes in hal-2 mutants, and markers of PC-dependent movement and function are restored in hal-2; syp double mutants. These and other data indicate that SYP proteins can impede pairing and that HAL-2 promotes pairing predominantly but not exclusively by counteracting this inhibition, thereby enabling activation and regulation of PC function. HAL-2 concentrates in the germ cell nucleoplasm and colocalizes with SYP proteins in nuclear aggregates when SC assembly is prevented. We propose that HAL-2 functions to shepherd SYP proteins prior to licensing of SC assembly, preventing untimely interactions between SC precursors and chromosomes and allowing sufficient accumulation of precursors for rapid cooperative assembly upon homology verification.

  18. The pairing theory of polarons in real- and impulse spaces

    International Nuclear Information System (INIS)

    Dzhumanov, S.; Abboudy, S.; Baratov, A.A.

    1995-07-01

    A consistent pairing theory of carriers in real- and impulse spaces is developed. The pairing of different free (F), delocalized (D) and self-trapped (S) carriers in real-space, leading to the formation of various bipolaronic states are considered within the continuum model and adiabatic approximation taking into account the combined effect of the short- and long-range components of electron-lattice interaction with and without electron correlation. The formation possibility of D- and S-bipolarons as a function of ε ∞ /ε 0 are shown. The pairing scenarios of carriers in k-space leading to the formation of different bipolarons (including also Cooper pairs dynamic bipolarons) are considered within the generalized BCS-like model taking into account the combined phonon and polaron-bag mediated processes. It is shown that the pure BCS pairing picture is the particular case of the general BCS-like one. The possible relevance of the obtained results to high-T c superconductors is discussed in details in the framework of a novel two-stage Fermi-Bose-liquid scenarios of superconductivity which is caused by single particle and pair condensation of an attracting bipolarons. (author). 51 refs, 6 figs

  19. Impulsiveness does not prevent cooperation from emerging but reduces its occurrence: an experiment with zebra finches.

    Science.gov (United States)

    Chia, Camille; Dubois, Frédérique

    2017-08-17

    Reciprocal altruism, the most probable mechanism for cooperation among unrelated individuals, can be modelled as a Prisoner's Dilemma. This game predicts that cooperation should evolve whenever the players, who expect to interact repeatedly, make choices contingent to their partner's behaviour. Experimental evidence, however, indicates that reciprocity is rare among animals. One reason for this would be that animals are very impulsive compared to humans. Several studies have reported that temporal discounting (that is, strong preferences for immediate benefits) has indeed a negative impact on the occurrence of cooperation. Yet, the role of impulsive action, another facet of impulsiveness, remains unexplored. Here, we conducted a laboratory experiment in which male and female zebra finches (Taenyopigia guttata) were paired assortatively with respect to their level of impulsive action and then played an alternating Prisoner's Dilemma. As anticipated, we found that self-controlled pairs achieved high levels of cooperation by using a Generous Tit-for-Tat strategy, while impulsive birds that cooperated at a lower level, chose to cooperate with a fixed probability. If the inability of impulsive individuals to use reactive strategies are due to their reduced working memory capacity, thus our findings might contribute to explaining interspecific differences in cooperative behaviour.

  20. Agreement between the Government of Australia and the Government of the Republic of the Philippines concerning co-operation in peaceful uses of nuclear energy and the transfer of nuclear material

    International Nuclear Information System (INIS)

    1983-01-01

    Australia and the Philippines, both parties to the Treaty on the Non-Proliferation of Nuclear Weapons, have agreed to cooperate in the peaceful uses of nuclear energy, including research and training, exchange of unclassified information, and projects of mutual interest. The agreement applies to all nuclear material transferred for peaceful purposes between the two countries and to material derived from that transferred material. The treaty entered into force on the 11th May 1982

  1. Innovative Improvement and Intensification of Business Relationships Supported by Cooperative Networks

    Science.gov (United States)

    Vančová, Viera; Čambál, Miloš; Cagáňová, Dagmar

    2012-12-01

    Nowadays, the opportunity for companies to be involved in cluster initiatives and international business associations is a major factor that contributes to the increase of their innovative potential. Companies organized in technological clusters have greater access to mutual business contacts, faster information transfer and deployment of advanced technologies. These companies cooperate more frequently with universities and research - development institutions on innovative projects. An important benefit of cluster associations is that they create a suitable environment for innovation and the transfer of knowledge by means of international cooperation and networking. This supportive environment is not easy to access for different small and mediumsized companies, who are not members of any clusters or networks. Supplier-customer business channels expand by means of transnational networks and exchanges of experience. Knowledge potential is broadened and joint innovative projects are developed. Reflecting the growing importance of clusters as driving forces of economic and regional development, a number of cluster policies and initiatives have emerged in the last few decades, oriented to encourage the establishment of new clusters, to support existing clusters, or to assist the development of transnational cooperation. To achieve the goals of the Europe 2020 Strategy, European countries should have an interest in building strong clusters and developing cluster cooperation by sharing specialized research infrastructures and testing facilities and facilitating knowledge transfer for crossborder cooperation. This requires developing a long term joint strategy in order to facilitate the development of open global clusters and innovative small and medium entrepreneurs.

  2. Solvent effect on the intermolecular proton transfer of the Watson and Crick guanine-cytosine and adenine-thymine base pairs: a polarizable continuum model study.

    Science.gov (United States)

    Romero, Eduardo E; Hernandez, Florencio E

    2018-01-03

    Herein we present our results on the study of the double proton transfer (DPT) mechanism in the adenine-thymine (AT) and guanine-cytosine (GC) base pairs, both in gas phase and in solution. The latter was modeled using the polarizable continuum method (PCM) in different solvents. According to our DFT calculations, the DPT may occur for both complexes in a stepwise mechanism in condensate phase. In gas phase only the GC base pair exhibits a concerted DPT mechanism. Using the Wigner's tunneling corrections to the transition state theory we demonstrate that such corrections are important for the prediction of the rate constants of both systems in gas and in condensate phase. We also show that (i) as the polarity of the medium decreases the equilibrium constant of the DPT reaction increases in both complexes, and (ii) that the equilibrium constant in the GC complex is four orders of magnitude larger than in AT. This observation suggests that the spontaneous mutations in DNA base pairs are more probable in GC than in AT.

  3. Silyl Ketene Acetals/B(C6F53 Lewis Pair-Catalyzed Living Group Transfer Polymerization of Renewable Cyclic Acrylic Monomers

    Directory of Open Access Journals (Sweden)

    Lu Hu

    2018-03-01

    Full Text Available This work reveals the silyl ketene acetal (SKA/B(C6F53 Lewis pair-catalyzed room-temperature group transfer polymerization (GTP of polar acrylic monomers, including methyl linear methacrylate (MMA, and the biorenewable cyclic monomers γ-methyl-α-methylene-γ-butyrolactone (MMBL and α-methylene-γ-butyrolactone (MBL as well. The in situ NMR monitored reaction of SKA with B(C6F53 indicated the formation of Frustrated Lewis Pairs (FLPs, although it is sluggish for MMA polymerization, such a FLP system exhibits highly activity and living GTP of MMBL and MBL. Detailed investigations, including the characterization of key reaction intermediates, polymerization kinetics and polymer structures have led to a polymerization mechanism, in which the polymerization is initiated with an intermolecular Michael addition of the ester enolate group of SKA to the vinyl group of B(C6F53-activated monomer, while the silyl group is transferred to the carbonyl group of the B(C6F53-activated monomer to generate the single-monomer-addition species or the active propagating species; the coordinated B(C6F53 is released to the incoming monomer, followed by repeated intermolecular Michael additions in the subsequent propagation cycle. Such neutral SKA analogues are the real active species for the polymerization and are retained in the whole process as confirmed by experimental data and the chain-end analysis by matrix-assisted laser desorption/ionization time of flight mass spectroscopy (MALDI-TOF MS. Moreover, using this method, we have successfully synthesized well-defined PMMBL-b-PMBL, PMMBL-b-PMBL-b-PMMBL and random copolymers with the predicated molecular weights (Mn and narrow molecular weight distribution (MWD.

  4. Visualising Actor Network for Cooperative Systems in Marine Technology

    DEFF Research Database (Denmark)

    Pan, Yushan; Finken, Sisse

    2016-01-01

    Awareness is a concept familiar to specialists within the field of Computer Supported Cooperative Work (CSCW). It is superior for analysing and describing some of the ad hoc work activities that unfold in cooperation. Such informal activities are outside the scope of engineers’ formal models, whi...... that shape computer systems. The aim, thus, is to portray cooperative work in a way that can be valuable for engineers implementing marine technology. We do so by way of presenting a transferring technique (2T) using insights from the CSCW field and Actor Network Theory (ANT)....

  5. Superconducting properties of the η-pairing state in the Penson-Kolb-Hubbard model

    International Nuclear Information System (INIS)

    Czart, W.R.; Robaszkiewicz, S.

    2004-01-01

    The Penson-Kolb-Hubbard model, i.e. the Hubbard model with the pair-hopping interaction J is studied. We focus on the properties of the superconducting state with the Cooper-pair center-of mass momentum q Q(η-phase). The transition into the η-phase, which is favorized by the repulsive J (J c |, dependent on band filling, on-site interaction U and band structure, and the system never exhibits standard BCS-like features. This is in obvious contrast with the properties of the isotropic s-wave state, stabilized by the attractive J and attractive U, which exhibit at T = 0 a smooth crossover from the BCS-like limit to that of tightly bound pairs with increasing pairing strength. (author)

  6. Transfer vibration through spine

    OpenAIRE

    Benyovszky, Adam

    2012-01-01

    Transfer Vibration through Spine Abstract In the bachelor project we deal with the topic of Transfer Vibration through Spine. The problem of TVS is trying to be solved by the critical review method. We analyse some diagnostic methods and methods of treatment based on this principle. Close attention is paid to the method of Transfer Vibration through Spine that is being currently solved by The Research Institute of Thermomechanics in The Czech Academy of Sciences in cooperation with Faculty of...

  7. Wireless power transfer: control algorithm to transfer the maximum power

    OpenAIRE

    Rojas Urbano, Javier Arturo

    2016-01-01

    This job is developed as part of “Health aware enhanced range wireless power transfer systems", known as ETHER. It is a cooperation project where Universidad Politécnica de Madrid (UPM) and Universidad Politécnica de Cataluña (UPC) research groups are mainly involved. ETHER objective is to develop a wireless power transfer system for medical applications, specifically a pacemaker charger to improve patient’s lifestyle decreasing the number of required operations to replace pacemaker batter...

  8. Energy transfer in plasmonic systems

    International Nuclear Information System (INIS)

    Pustovit, Vitaliy N; Urbas, Augustine M; Shahbazyan, Tigran V

    2014-01-01

    We present our results on energy transfer between donor and acceptor molecules or quantum dots near a plasmonic nanoparticle. In such systems, the Förster resonance energy transfer is strongly modified due to plasmon-mediated coupling between donors and acceptors. The transfer efficiency is determined by a competition between transfer, radiation and dissipation that depends sensitively on system parameters. When donor and accepror spectral bands overlap with dipole surface plasmon resonance, the dominant transfer mechanism is through plasmon-enhanced radiative coupling. When transfer takes place from an ensemble of donors to an acceptor, a cooperative amplification of energy transfer takes place in a wide range of system parameters. (paper)

  9. Cooperative endeavors: A case study of success

    Energy Technology Data Exchange (ETDEWEB)

    Baker, J. [Ford Motor Co., Dearborn, MI (United States)

    1997-12-31

    Partnerships and cooperative agreements abound in the environmental arena today. This paper briefly highlights the collaborative approach used by the International Cooperative for Ozone Layer Protection (ICOLP). ICOLP has helped international members and non-members to eliminate most of the ozone-depleting solvents from manufacturing processes through the exchange of technical information in a non-proprietary manner. By using alternatives, companies and governments have realized savings in the multiple millions of dollars. Advantages of participating in cooperative environmental partnerships may include: (1) improved access and exchange of information, (2) cost minimization, (3) promotion and facilitation of business opportunities, (4) improved dialogue between groups, (5) coordinated approach to complex issues, and (6) technology development and transfer opportunities.

  10. Helping enhances productivity in campo flicker ( Colaptes campestris) cooperative groups

    Science.gov (United States)

    Dias, Raphael Igor; Webster, Michael S.; Macedo, Regina H.

    2015-06-01

    Reproductive adults in many bird species are assisted by non-breeding auxiliary helpers at the nest, yet the impact of auxiliaries on reproduction is variable and not always obvious. In this study, we tested Hamilton's rule and evaluated the effect of auxiliaries on productivity in the facultative cooperative breeder campo flicker ( Colaptes campestris campestris). Campo flickers have a variable mating system, with some groups having auxiliaries and others lacking them (i.e., unassisted pairs). Most auxiliaries are closely related to the breeding pair (primary auxiliaries), but some auxiliaries (secondary auxiliaries) are unrelated females that joined established groups. We found no effect of breeder quality (body condition) or territory quality (food availability) on group productivity, but the presence of auxiliaries increased the number of fledglings produced relative to unassisted pairs. Nonetheless, the indirect benefit of helping was small and did not outweigh the costs of delayed breeding and so seemed insufficient to explain the evolution of cooperative breeding in campo flickers. We concluded that some ecological constraints must limit dispersal or independent breeding, making staying in the group a "best-of-a-bad-job" situation for auxiliaries.

  11. Enhancement of international cooperation and experience exchange: international and regional cooperation in nuclear technology

    International Nuclear Information System (INIS)

    Henderson, R.R.

    1987-01-01

    This paper will explore methods that have been effective in accomplishing broad-based technology transfer relationships between international commercial nuclear organizations, and have enhanced the benefits from such relationships through mutual participation in the development of new technology. The factors involved in accomplishing technology transfer will be examined based on the 25 years of Westinghouse experience in establishing successful nuclear technology relationships with over 20 different associates world-wide. This will include information pertaining to organization, training, consultation, technical information transmission, and other important aspects of technology transfer. Additionally, the methodology of enhancing and increasing the benefits of technology transfer through cooperative development programs as produced and promoted by Weatinghouse with its associates will be examined. This will include reviews of several significant copperative programs, such as the programs for the Advanced Pressurized Water Reactor and the Integrated Protection and Control Systems for future plants. (author)

  12. e+e- Pair production from 10 GeV to 10 ZeV

    International Nuclear Information System (INIS)

    Klein, Spencer R.

    2006-01-01

    At very high energies, pair production (γ->e + e - ) exhibits many interesting features. The momentum transfer from the target is very small, so the reaction probes the macroscopic properties of the target, rather than individual nuclei. Interference between interactions with different atoms reduces the pair production cross section considerably below the Bethe-Heitler values. At very high energies, photonuclear interactions may outnumber pair production. In contrast, in crystals, the interaction amplitudes may add coherently, greatly increasing the cross sections. Pair production in matter-free magnetic fields is also possible. The highest energy pair production occurs at high-energy particle colliders. This article will compare pair production in these very different regimes

  13. Deciphering the Sox-Oct partner code by quantitative cooperativity measurements.

    Science.gov (United States)

    Ng, Calista K L; Li, Noel X; Chee, Sheena; Prabhakar, Shyam; Kolatkar, Prasanna R; Jauch, Ralf

    2012-06-01

    Several Sox-Oct transcription factor (TF) combinations have been shown to cooperate on diverse enhancers to determine cell fates. Here, we developed a method to quantify biochemically the Sox-Oct cooperation and assessed the pairing of the high-mobility group (HMG) domains of 11 Sox TFs with Oct4 on a series of composite DNA elements. This way, we clustered Sox proteins according to their dimerization preferences illustrating that Sox HMG domains evolved different propensities to cooperate with Oct4. Sox2, Sox14, Sox21 and Sox15 strongly cooperate on the canonical element but compete with Oct4 on a recently discovered compressed element. Sry also cooperates on the canonical element but binds additively to the compressed element. In contrast, Sox17 and Sox4 cooperate more strongly on the compressed than on the canonical element. Sox5 and Sox18 show some cooperation on both elements, whereas Sox8 and Sox9 compete on both elements. Testing rationally mutated Sox proteins combined with structural modeling highlights critical amino acids for differential Sox-Oct4 partnerships and demonstrates that the cooperativity correlates with the efficiency in producing induced pluripotent stem cells. Our results suggest selective Sox-Oct partnerships in genome regulation and provide a toolset to study protein cooperation on DNA.

  14. TIT FOR TAT in sticklebacks and the evolution of cooperation

    Science.gov (United States)

    Milinski, Manfred

    1987-01-01

    The problems of achieving mutual cooperation can be formalized in a game called the Prisoner's Dilemma in which selfish defection is always more rewarding than cooperation1. If the two protagonists have a certain minimum probability of meeting again a strategy called TIT FOR TAT is very successful2. In TIT FOR TAT the player cooperates on the first move and thereafter does whatever the opponent did on the previous move. I have studied the behaviour of fish when confronting a potential predator, because conflicts can arise within pairs of fish in these circumstances which I argue resemble a series of games of Prisoner's Dilemma. Using a system of mirrors, single three-spined sticklebacks (Gasterosteus aculeatus) approaching a live predator were provided with either a simulated cooperating companion or a simulated defecting one. In both cases the test fish behaved according to TIT FOR TAT supporting the hypothesis that cooperation can evolve among egoists.

  15. Cooperative electrocatalytic alcohol oxidation with electron-proton-transfer mediators

    Science.gov (United States)

    Badalyan, Artavazd; Stahl, Shannon S.

    2016-07-01

    The electrochemical oxidation of alcohols is a major focus of energy and chemical conversion efforts, with potential applications ranging from fuel cells to biomass utilization and fine-chemical synthesis. Small-molecule electrocatalysts for processes of this type are promising targets for further development, as demonstrated by recent advances in nickel catalysts for electrochemical production and oxidation of hydrogen. Complexes with tethered amines that resemble the active site of hydrogenases have been shown both to catalyse hydrogen production (from protons and electrons) with rates far exceeding those of such enzymes and to mediate reversible electrocatalytic hydrogen production and oxidation with enzyme-like performance. Progress in electrocatalytic alcohol oxidation has been more modest. Nickel complexes similar to those used for hydrogen oxidation have been shown to mediate efficient electrochemical oxidation of benzyl alcohol, with a turnover frequency of 2.1 per second. These compounds exhibit poor reactivity with ethanol and methanol, however. Organic nitroxyls, such as TEMPO (2,2,6,6-tetramethyl-1-piperidine N-oxyl), are the most widely studied electrocatalysts for alcohol oxidation. These catalysts exhibit good activity (1-2 turnovers per second) with a wide range of alcohols and have great promise for electro-organic synthesis. Their use in energy-conversion applications, however, is limited by the high electrode potentials required to generate the reactive oxoammonium species. Here we report (2,2‧-bipyridine)Cu/nitroxyl co-catalyst systems for electrochemical alcohol oxidation that proceed with much faster rates, while operating at an electrode potential a half-volt lower than that used for the TEMPO-only process. The (2,2‧-bipyridine)Cu(II) and TEMPO redox partners exhibit cooperative reactivity and exploit the low-potential, proton-coupled TEMPO/TEMPOH redox process rather than the high-potential TEMPO/TEMPO+ process. The results show how

  16. Centromere pairing by a plasmid-encoded type I ParB protein

    DEFF Research Database (Denmark)

    Ringgaard, Simon; Löwe, Jan; Gerdes, Kenn

    2007-01-01

    The par2 locus of Escherichia coli plasmid pB171 encodes two trans-acting proteins, ParA and ParB, and two cis-acting sites, parC1 and parC2, to which ParB binds cooperatively. ParA is related to MinD and oscillates in helical structures and thereby positions ParB/parC-carrying plasmids regularly......, hence identifying the N terminus of ParB as a requirement for ParB-mediated centromere pairing. These observations suggest that centromere pairing is an important intermediate step in plasmid partitioning mediated by the common type I loci....

  17. Watson-Crick base pairing controls excited-state decay in natural DNA.

    Science.gov (United States)

    Bucher, Dominik B; Schlueter, Alexander; Carell, Thomas; Zinth, Wolfgang

    2014-10-13

    Excited-state dynamics are essential to understanding the formation of DNA lesions induced by UV light. By using femtosecond IR spectroscopy, it was possible to determine the lifetimes of the excited states of all four bases in the double-stranded environment of natural DNA. After UV excitation of the DNA duplex, we detected a concerted decay of base pairs connected by Watson-Crick hydrogen bonds. A comparison of single- and double-stranded DNA showed that the reactive charge-transfer states formed in the single strands are suppressed by base pairing in the duplex. The strong influence of the Watson-Crick hydrogen bonds indicates that proton transfer opens an efficient decay path in the duplex that prohibits the formation or reduces the lifetime of reactive charge-transfer states. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Does a frozen embryo transfer ameliorate the effect of elevated progesterone seen in fresh transfer cycles?

    Science.gov (United States)

    Healy, Mae Wu; Patounakis, George; Connell, Matt T; Devine, Kate; DeCherney, Alan H; Levy, Michael J; Hill, Micah J

    2016-01-01

    To compare the effect of progesterone (P) on the day of trigger in fresh assisted reproduction technology (ART) transfer cycles versus its effect on subsequent frozen embryo transfer (FET) cycles. Retrospective cohort study. Large private ART practice. Fresh autologous and FET cycles from 2011-2013. None. Live birth. A paired analysis of patients who underwent both a fresh transfer and subsequent FET cycle and an unpaired analysis of data from all fresh transfer cycles and all FET cycles were performed. We analyzed 1,216 paired and 4,124 unpaired cycles, and P was negatively associated with birth in fresh but not FET cycles in all analyses. Interaction testing of P and cycle type indicated P had a different association with birth in fresh versus FET cycles. When P was ≥ 2 ng/mL at the time of trigger, live birth was more likely in FET versus fresh cycles in the paired analysis (47% vs. 10%), in the unpaired analysis (51% vs. 14%), and in unpaired, good blastocyst only transfer subgroup (51% vs. 29%). Live birth was similar in FET cycles, with P ≥ 2 ng/mL versus P cycles, with P ≥ 2 ng/mL versus P cycle were negatively associated with live birth in the fresh transfer cycles but not in subsequent FET cycles. Freezing embryos and performing a subsequent FET cycle ameliorates the effect of elevated P on live-birth rates. Published by Elsevier Inc.

  19. Differential bremsstrahlung and pair production cross sections at high energies

    International Nuclear Information System (INIS)

    Olsen, Haakon A.

    2003-01-01

    Detailed differential cross sections for high energy bremsstrahlung and pair production are derived with specific attention to the differences between the two processes, which are considerable. For the integrated cross sections, which are the only cross sections specifically known until now, the final state integration theorem guarantees that the exact cross section formulas can be exchanged between bremsstrahlung and pair production by the same substitution rules as for the Born-approximation Bethe-Heitler cross sections, for any amount of atomic screening. In fact the theorem states that the Coulomb corrections to the integrated bremsstrahlung and pair production cross sections are identical for any amount of screening. The analysis of the basic differential cross sections leads to fundamental physical differences between bremsstrahlung and pair production. Coulomb corrections occur for pair production in the strong electric field of the atom for 'large' momentum transfer of the order of mc. For bremsstrahlung, on the other hand, the Coulomb corrections take place at a 'large' distance from the atom of the order of ((ℎ/2π)/mc)ε, with a 'small' momentum transfer mc/ε, where ε is the initial electron energy in units of mc 2 . And the Coulomb corrections can be large, of the order of larger than (Z/137) 2 , which is considerably larger than the integrated cross section corrections

  20. Cross-border knowledge transfer and innovation in the European neighbourhood

    DEFF Research Database (Denmark)

    Makkonen, Teemu; Williams, Allan; Weidenfeld, Adi

    2018-01-01

    . This research gap is addressed here via interview data collected from participants in tourism related EU-funded projects in the Finnish-Russian cross-border region. These underline the importance of EU-funding in facilitating knowledge transfer and innovation between Finland and Russia. While language issues......Knowledge transfer and innovation cooperation between the EU and its neighbours has remained weakly developed. To promote this cooperation, the EU has set up initiatives for the European neighbourhood. The issue has, however, received very limited scholarly attention in the field of tourism......, and differences in business culture and administrative/legislative systems between the two countries, constitute barriers for practical cross-border cooperation, it is cross-border differences in culture and technological capabilities that drive cross-border knowledge transfer and innovation in the cross...

  1. Fiscal 1998 research report. Feasibility study on international cooperation for technology transfer; 1998 nendo chosa hokokusho. Gijutsu iten ni kakawaru kokusai kanosei chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    CTI (Climate Technology Initiative) is a framework for use by developed countries in international cooperation and voluntary promotion of the development and diffusion of technologies contributory to reduction of greenhouse gas emissions. The CTI's activity goal is to accelerate the transfer and diffusion of technologies for climate change control. As the first step toward personnel development programs relating to energy efficiency, CTI organized its workshop on that theme. The results of the workshop have been examined, and its achievements were reported at COP4 meeting, while responses by participatory countries were studied to evaluate the potential of international cooperation with regard to personnel development for reducing greenhouse gas emissions. In fiscal 1998, the CTI workshop 'Energy Efficiency' was held. The participants from developing countries understood the necessity and importance of energy saving enough through discussions in the workshop, and announced their message toward the world at COP4 meeting. (NEDO)

  2. Unstable Hoogsteen base pairs adjacent to echinomycin binding sites within a DNA duplex

    International Nuclear Information System (INIS)

    Gilbert, D.E.; van der Marel, G.A.; van Boom, J.H.; Feigon, J.

    1989-01-01

    The bisintercalation complex present between the DNA octamer [d(ACGTACGT)] 2 and the cyclic octadepsipeptide antibiotic echinomycin has been studied by one- and two-dimensional proton NMR, and the results obtained have been compared with the crystal structures of related DNA-echinomycin complexes. Two echinomycins are found to bind cooperatively to each DNA duplex at the CpG steps, with the two quinoxaline rings of each echinomycin bisintercalating between the C·G and A·T base pairs. At low temperatures, the A·T base pairs on either side of the intercalation site adopt the Hoogsteen conformation, as observed in the crystal structures. However, as the temperature is raised, the Hoogsteen base pairs in the interior of the duplex are destabilized and are observed to be exchanging between the Hoogsteen base pair and either an open or a Watson-Crick base-paired state. The terminal A·T base pairs, which are not as constrained by the helix as the internal base pairs, remain stably Hoogsteen base-paired up to at least 45 degree C. The implications of these results for the biological role of Hoogsteen base pairs in echinomycin-DNA complexes in vivo are discussed

  3. Detection of no-model input-output pairs in closed-loop systems.

    Science.gov (United States)

    Potts, Alain Segundo; Alvarado, Christiam Segundo Morales; Garcia, Claudio

    2017-11-01

    The detection of no-model input-output (IO) pairs is important because it can speed up the multivariable system identification process, since all the pairs with null transfer functions are previously discarded and it can also improve the identified model quality, thus improving the performance of model based controllers. In the available literature, the methods focus just on the open-loop case, since in this case there is not the effect of the controller forcing the main diagonal in the transfer matrix to one and all the other terms to zero. In this paper, a modification of a previous method able to detect no-model IO pairs in open-loop systems is presented, but adapted to perform this duty in closed-loop systems. Tests are performed by using the traditional methods and the proposed one to show its effectiveness. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  4. Universal spectral signatures in pnictides and cuprates: the role of quasiparticle-pair coupling.

    Science.gov (United States)

    Sacks, William; Mauger, Alain; Noat, Yves

    2017-11-08

    Understanding the physical properties of a large variety of high-T c superconductors (SC), the cuprate family as well as the more recent iron-based superconductors, is still a major challenge. In particular, these materials exhibit the 'peak-dip-hump' structure in the quasiparticle density of states (DOS). The origin of this structure is explained within our pair-pair interaction (PPI) model: The non-superconducting state consists of incoherent pairs, a 'Cooper-pair glass' which, due to the PPI, undergoes a Bose-like condensation below T c to the coherent SC state. We derive the equations of motion for the quasiparticle operators showing that the DOS 'peak-dip-hump' is caused by the coupling between quasiparticles and excited pair states, or 'super-quasiparticles'. The renormalized SC gap function becomes energy-dependent and non retarded, reproducing accurately the experimental spectra of both pnictides and cuprates, despite the large difference in gap value.

  5. International cooperation in the peaceful use of nuclear energy

    International Nuclear Information System (INIS)

    Jacke, S.; Stein, G.

    1988-01-01

    The article in hand reviews the scenario and organisation of the conference together with the results achieved (non-proliferation strategies with regard to technological cooperation in the nuclear field, feasible means of cooperation), saying that judged by the non-favourable conditions at the start, the fruitful dialogue between developing countries and highly industrialised countries that has set in at this conference will have to be filed on the credit side. Another important result is that one came to realize that the transfer of know-how must be very carefully prepared and accompanied by very close cooperation right from the start. (orig./DG) [de

  6. Cooperation driven coherence: Brains working hard together.

    Science.gov (United States)

    Bezerianos, Anastasios; Sun, Yu; Chen, Yu; Woong, Kian Fong; Taya, Fumihiko; Arico, Pietro; Borghini, Gianluca; Babiloni, Fabio; Thakor, Nitish

    2015-01-01

    The current study aims to look at the difference in coupling of EEG activity of participant pairs while they perform a cooperative, concurrent, independent yet different task at high and low difficulty levels. Participants performed the National Aeronautics and Space Administration (NASA) designed Multi-Attribute Task Battery (MATB-II) task which simulates a pilot and copilot operating an aircraft. Each participant in the pair was responsible for 2 out of 4 subtasks which were independent and different from one another while all tasks occurs concurrently in real time with difficulty levels being the frequency that adjustments are required for each subtask. We found that as the task become more difficult, there was more coupling between the pilot and copilot.

  7. Radiation- and pair-loaded shocks

    Science.gov (United States)

    Lyutikov, Maxim

    2018-06-01

    We consider the structure of mildly relativistic shocks in dense media, taking into account the radiation and pair loading, and diffusive radiation energy transfer within the flow. For increasing shock velocity (increasing post-shock temperature), the first important effect is the efficient energy redistribution by radiation within the shock that leads to the appearance of an isothermal jump, whereby the flow reaches the final state through a discontinuous isothermal transition. The isothermal jump, on scales much smaller than the photon diffusion length, consists of a weak shock and a quick relaxation to the isothermal conditions. Highly radiation-dominated shocks do not form isothermal jump. Pair production can mildly increase the overall shock compression ratio to ≈10 (4 for matter-dominated shocks and 7 of the radiation-dominated shocks).

  8. Nucleic Acid Base Analog FRET-Pair Facilitating Detailed Structural Measurements in Nucleic Acid Containing Systems

    DEFF Research Database (Denmark)

    Börjesson, Karl; Preus, Søren; El-Sagheer, Afaf

    2009-01-01

    We present the first nucleobase analog fluorescence resonance energy transfer (FRET)-pair. The pair consists of tCO, 1,3-diaza-2-oxophenoxazine, as an energy donor and the newly developed tC(nitro), 7-nitro-1,3-diaza-2-oxophenothiazine, as an energy acceptor. The FRET-pair successfully monitors d...

  9. EFEKTIVITAS PENGGUNAAN METODE THINK PAIR SHARE DALAM PEMBELAJARAN EKONOMI POKOK BAHASAN PEMBENTUKAN HARGA PASAR DI SMP

    OpenAIRE

    Joko Widodo

    2007-01-01

    The result of teaching-learning by using Think Pair Share method can improve the students’ activities. It can be seen from the steps to apply the Think Pair Share method that focused on student-centre. Think pair share learning has a simple structure, as a basic of the development ‘cooperative class’ which can help the learning process actively for students, thus it can improve the students’ study result. Students actively can show their ability to discuss and share and express the an...

  10. Efektivitas Penggunaan Metode Think Pair Share Dalam Pembelajaran Ekonomi Pokok Bahasan Pembentukan Harga Pasar Di SMP

    OpenAIRE

    Widodo, Joko

    2007-01-01

    The result of teaching-learning by using Think Pair Share method can improve the students’ activities. It can be seen from the steps to apply the Think Pair Share method that focused on student-centre. Think pair share learning has a simple structure, as a basic of the development ‘cooperative class’ which can help the learning process actively for students, thus it can improve the students’ study result. Students actively can show their ability to discuss and share and express the an...

  11. 14 CFR 1260.69 - Electronic funds transfer payment methods.

    Science.gov (United States)

    2010-01-01

    ... Government by electronic funds transfer through the Treasury Fedline Payment System (FEDLINE) or the... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Electronic funds transfer payment methods... COOPERATIVE AGREEMENTS General Special Conditions § 1260.69 Electronic funds transfer payment methods...

  12. Cooperation under Predation Risk: Experiments on Costs and Benefits

    Science.gov (United States)

    Milinski, Manfred; Luthi, Jean H.; Eggler, Rolf; Parker, Geoffrey A.

    1997-06-01

    Two fish that cooperatively inspect a predator may have negotiated the share of the risk that each takes. A test of both the costs of predator inspection dependent on the distance from which the predator is approached and the potential benefits of cooperation was carried out strictly experimentally. We made either singletons or pairs of dead sticklebacks, Gasterosteus aculeatus, approach hungry pike, Esox lucius, by remote control according to an algorithm that mimicked natural inspection. The predation risk of both single inspectors and parallel inspecting pairs increased with closer inspection distances. A member of an inspecting pair had only about half the risk of that of a single inspector. In pairs, a companion diluted the lead fish's risk of being caught, depending on its distance behind the leader. The absolute risk difference between leader and follower was greatest for close inspection distances and decreased further away from the predator. The leader's relative risk increased with its distance ahead of the laggard. However, for a given distance between leader and laggard, the relative risks to the two fish remained similar with distance from the predator. The cost side of the inequalities that define a 'Prisoner's Dilemma' has thus been measured for this system. In a second experiment the 'attack deterrence hypothesis' of predator inspection (i.e. inspection decreases attack probability) was tested. The pike was offered a choice between two sticklebacks, one of which had carried out a predator inspection visit. There was no indication of attack deterrence through predator inspection.

  13. Incoherently Coupled Grey-Grey Spatial Soliton Pairs in Biased Two-Photon Photovoltaic Photorefractive Crystals

    International Nuclear Information System (INIS)

    Su Yanli; Jiang Qichang; Ji Xuanmang

    2010-01-01

    The incoherently coupled grey-grey screening-photovoltaic spatial soliton pairs are predicted in biased two-photon photovoltaic photorefractive crystals under steady-state conditions. These grey-grey screening-photovoltaic soliton pairs can be established provided that the incident beams have the same polarization, wavelength, and are mutually incoherent. The grey-grey screening-photovoltaic soliton pairs can be considered as the united form of grey-grey screening soliton pairs and open or closed-circuit grey-grey photovoltaic soliton pairs. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  14. Modeling the bacterial photosynthetic reaction center. VII. Full simulation of the intervalence hole-transfer absorption spectrum of the special-pair radical cation

    International Nuclear Information System (INIS)

    Reimers, Jeffrey R.; Hush, Noel S.

    2003-01-01

    ENDOR data suggests that the special-pair radical cation P + from Rhodobacter sphaeroides is 68% localized on P L while simple interpretations of FTIR difference spectra based primarily on intensity information, but to some extent also bandwidths, suggest near-complete charge localization. We provide a complete a priori spectral simulation of the spectrum of P + in the range 0-5000 cm-1, including explicit treatment of the high-resolution vibrational transitions, the low-resolution hole-transfer absorption centered at 2700 cm-1, and the resonance with the SHOMO to HOMO transition at 2200 cm-1 that resolve the issues concerning the nature of P + . The description of the vibrational aspects of the problem were taken from results of previous density-functional calculations, and a qualitatively realistic large number of vibrational modes (50 antisymmetric and 18-20 symmetric) were included. To facilitate the calculations, a new representation of the vibronic-coupling Hamiltonian for intervalence hole-transfer or electron-transfer problems is introduced, allowing the spectrum to be simulated efficiently using only up to 4x10 9 vibronic basis functions and leading also to new general analytical relationships. Observed spectra are fitted using seven adjustable chemical parameters describing the interactions between the four electronic states involved. The resulting fits provide unique descriptions of the parameters that are insensitive to the source of the observed spectrum or the nature of the symmetric modes used in the model, and all fitted parameters are found to be close in value to those from independent estimates. We determine the electronic coupling, antisymmetric-mode reorganization energy, and redox asymmetry to be J=0.126±0.002 eV, λ=0.139±0.003 eV, and E 0 =0.069±0.002 eV, respectively. Our description forms the basis of understanding for a wide range of other properties observed for Rhodobacter sphaeroides mutants, as well as the properties of the

  15. Conditional imitation might promote cooperation under high temptations to defect

    Science.gov (United States)

    Dai, Qionglin; Li, Haihong; Cheng, Hongyan; Qian, Xiaolan; Zhang, Mei; Yang, Junzhong

    2012-07-01

    In this paper we introduce a conditional imitation rule into an evolutionary game, in which the imitation probabilities of individuals are determined by a function of payoff difference and two crucial parameters μ and σ. The parameter μ characterizes the most adequate goal for individuals and the parameter σ characterizes the tolerance of individuals. By using the pair approximation method and numerical simulations, we find an anomalous cooperation enhancement in which the cooperation level shows a nonmonotonic variation with the increase of temptation. The parameter μ affects the regime of the payoff parameter which supports the anomalous cooperation enhancement, whereas the parameter σ plays a decisive role on the appearance of the nonmonotonic variation of the cooperation level. Furthermore, to give explicit implications for the parameters μ and σ we present an alterative form of the conditional imitation rule based on the benefit and the cost incurred to individuals during strategy updates. In this way, we also provide a phenomenological interpretation for the nonmonotonic behavior of cooperation with the increase of temptation. The results give a clue that a higher cooperation level could be obtained under adverse environments for cooperation by applying the conditional imitation rule, which is possible to be manipulated in real life. More generally, the results in this work might point out an efficient way to maintain cooperation in the risky environments to cooperators.

  16. Nuclear cooperation between Brazil and Federal Republic of Germany

    International Nuclear Information System (INIS)

    Syllus, C.

    1989-01-01

    The Brazil-Federal Republic of Germany Cooperation Agreement for constructing nuclear power plants, and the process of nuclear tecnology transfer in the different areas of design, are discussed. (M.C.K.) [pt

  17. Comparison effectiveness of cooperative learning type STAD with cooperative learning type TPS in terms of mathematical method of Junior High School students

    Science.gov (United States)

    Wahyuni, A.

    2018-05-01

    This research is aimed to find out whether the model of cooperative learning type Student Team Achievement Division (STAD) is more effective than cooperative learning type Think-Pair-Share in SMP Negeri 7 Yogyakarta. This research was a quasi-experimental research, using two experimental groups. The population of research was all students of 7thclass in SMP Negeri 7 Yogyakarta that consists of 5 Classes. From the population were taken 2 classes randomly which used as sample. The instrument to collect data was a description test. Measurement of instrument validity use content validity and construct validity, while measuring instrument reliability use Cronbach Alpha formula. To investigate the effectiveness of cooperative learning type STAD and cooperative learning type TPS on the aspect of student’s mathematical method, the datas were analyzed by one sample test. Comparing the effectiveness of cooperative learning type STAD and TPS in terms of mathematical communication skills by using t-test. Normality test was not conducted because the sample of research more than 30 students, while homogeneity tested by using Kolmogorov Smirnov test. The analysis was performed at 5% confidence level.The results show as follows : 1) The model of cooperative learning type STAD and TPS are effective in terms of mathematical method of junior high school students. 2). STAD type cooperative learning model is more effective than TPS type cooperative learning model in terms of mathematical methods of junior high school students.

  18. Coaction versus reciprocity in continuous-time models of cooperation.

    Science.gov (United States)

    van Doorn, G Sander; Riebli, Thomas; Taborsky, Michael

    2014-09-07

    Cooperating animals frequently show closely coordinated behaviours organized by a continuous flow of information between interacting partners. Such real-time coaction is not captured by the iterated prisoner's dilemma and other discrete-time reciprocal cooperation games, which inherently feature a delay in information exchange. Here, we study the evolution of cooperation when individuals can dynamically respond to each other's actions. We develop continuous-time analogues of iterated-game models and describe their dynamics in terms of two variables, the propensity of individuals to initiate cooperation (altruism) and their tendency to mirror their partner's actions (coordination). These components of cooperation stabilize at an evolutionary equilibrium or show oscillations, depending on the chosen payoff parameters. Unlike reciprocal altruism, cooperation by coaction does not require that those willing to initiate cooperation pay in advance for uncertain future benefits. Correspondingly, we show that introducing a delay to information transfer between players is equivalent to increasing the cost of cooperation. Cooperative coaction can therefore evolve much more easily than reciprocal cooperation. When delays entirely prevent coordination, we recover results from the discrete-time alternating prisoner's dilemma, indicating that coaction and reciprocity are connected by a continuum of opportunities for real-time information exchange. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Challenges of technical cooperation in the petroleum industry

    International Nuclear Information System (INIS)

    Al-Athel, S.A.

    1992-01-01

    The need and prospects for international technical cooperation in the petroleum industry are reviewed. Since it directly affects the survival of the inhabitants of the planet, environmental protection is a field that could enjoy maximum international cooperation; oil spills, product environmental hazards, waste minimization and disposal and oil field fires are the main areas identified. Technical cooperation in other areas of the industry, namely exploration, production, oil field development, refining and petrochemicals, may involve some controversy. Attention is drawn to the conflicting interests of multinational companies, who almost completely control the technology of these activities, and host developing countries. It is advocated that arrangements involving technology transfer should make provision for the growth of indigenous technology. (UK)

  20. Phase-driven collapse of the Cooper condensate in a nanosized superconductor

    Science.gov (United States)

    Ronzani, Alberto; D'Ambrosio, Sophie; Virtanen, Pauli; Giazotto, Francesco; Altimiras, Carles

    2017-12-01

    Superconductivity can be understood in terms of a phase transition from an uncorrelated electron gas to a condensate of Cooper pairs in which the relative phases of the constituent electrons are coherent over macroscopic length scales. The degree of correlation is quantified by a complex-valued order parameter, whose amplitude is proportional to the strength of the pairing potential in the condensate. Supercurrent-carrying states are associated with nonzero values of the spatial gradient of the phase. The pairing potential and several physical observables of the Cooper condensate can be manipulated by means of temperature, current bias, dishomogeneities in the chemical composition, or application of a magnetic field. Here we show evidence of complete suppression of the energy gap in the local density of quasiparticle states (DOS) of a superconducting nanowire upon establishing a phase difference equal to π over a length scale comparable to the superconducting coherence length. These observations are consistent with a complete collapse of the pairing potential in the center of the wire, in accordance with theoretical modeling based on the quasiclassical theory of superconductivity in diffusive systems. Our spectroscopic data, fully exploring the phase-biased states of the condensate, highlight the profound effect that extreme phase gradients exert on the amplitude of the pairing potential. Moreover, the sharp magnetic response (up to 27 mV/Φ0) observed near the onset of the superconducting gap collapse regime is exploited to realize magnetic flux detectors with noise-equivalent resolution as low as 260 n Φ0/√{Hz} .

  1. Fiscal 1998 research report. Feasibility study on international cooperation for technology transfer; 1998 nendo chosa hokokusho. Gijutsu iten ni kakawaru kokusai kanosei chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    CTI (Climate Technology Initiative) is a framework for use by developed countries in international cooperation and voluntary promotion of the development and diffusion of technologies contributory to reduction of greenhouse gas emissions. The CTI's activity goal is to accelerate the transfer and diffusion of technologies for climate change control. As the first step toward personnel development programs relating to energy efficiency, CTI organized its workshop on that theme. The results of the workshop have been examined, and its achievements were reported at COP4 meeting, while responses by participatory countries were studied to evaluate the potential of international cooperation with regard to personnel development for reducing greenhouse gas emissions. In fiscal 1998, the CTI workshop 'Energy Efficiency' was held. The participants from developing countries understood the necessity and importance of energy saving enough through discussions in the workshop, and announced their message toward the world at COP4 meeting. (NEDO)

  2. A Project in Support of International Nuclear Cooperation

    International Nuclear Information System (INIS)

    Kim, Myung Ro; Kim, Kyoung Pyo; Lee, Jeong Kong; Jung, Sung Hyon; Shim, Jae Sun

    2009-01-01

    The objective of this study is to establish the strategies of international cooperation in order to promote our nation's leading role in international community, to lay the foundation for the effective transfer of nuclear technology to developing countries, and to cope with the rapidly changing in the international nuclear communities. This study contains the work undertaken to promote multilateral cooperation within the framework of international nuclear related organizations and regional cooperative agreements and the relevant forums, to enhance bilateral cooperation with foreign nuclear related research institutes as well as to promote cooperation through the exchange of foreign scientists. As for multilateral cooperation, activities for promoting cooperation within the IAEA and regional cooperative frameworks are introduced. Regarding bilateral cooperation, activities for concluding arrangements and MOUs with foreign research institutes and for participation in joint nuclear coordinating committee meetings between Korea and other countries are presented. For promoting personnel exchanges, activities for inviting and utilizing foreign scientists and mutual discussions with foreign experts, who have visited KAERI, are also described. Continuous efforts to contributing towards the international community through utilizing Korea's experience gained in the process of technical self-reliance and development of human resources are needed. Also efforts to establish the foundation of international cooperation and to make inroad into overseas nuclear markets for export of our nuclear technologies should be made. Meanwhile in the bilateral cooperation, we need to beef up cooperation with U.S.A. and Canada through the joint committee for the joint export to third countries. It is expected that this study would be utilized as a basic material for the international cooperation of nuclear energy, especially for the KAERI's international cooperation in an effective way

  3. 48 CFR 970.2770-3 - Technology transfer and patent rights.

    Science.gov (United States)

    2010-10-01

    ... cooperative research and development agreements with public and private entities for purposes of conducting research and development and transferring technology to the private sector. In implementing the NCTTA, DOE....2770-3 Technology transfer and patent rights. The National Competitiveness Technology Transfer Act of...

  4. Cooperative Electrocatalytic O 2 Reduction Involving Co(salophen) with p- Hydroquinone as an Electron–Proton Transfer Mediator

    Energy Technology Data Exchange (ETDEWEB)

    Anson, Colin W. [Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States; Stahl, Shannon S. [Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States

    2017-12-01

    The molecular cobalt complex, Co(salophen), and para-hydroquinone (H2Q) serve as effective cocatalysts for the electrochemical reduction of O2 to water. Mechanistic studies reveal redox cooperativity between Co(salophen) and H2Q. H2Q serves as an electron-proton transfer mediator (EPTM) that enables electrochemical O2 reduction at higher potentials and with faster rates than is observed with Co(salophen) alone. Replacement of H2Q with the higher potential EPTM, 2-chloro-H2Q, allows for faster O2 reduction rates at higher applied potential. These results demonstrate a unique strategy to achieve improved performance with molecular electrocatalyst systems.

  5. Technology transfer and localization: A Framatome perspective

    International Nuclear Information System (INIS)

    Preneuf, R. de

    2000-01-01

    Localization and technology transfer have been important factors influencing the decision-making process in countries embarking on a nuclear power programme. It seems natural that relationships between donors and recipients of technology, beginning with sub-contracting, should evolve towards technology transfers and cooperation on an equal footing. France was both a receiver and a donor of technology transfer in the area of nuclear power. This paper describes the French experience in technology transfer and the lesson learned therefrom. (author)

  6. A two-level solvable model involving competing pairing interactions

    International Nuclear Information System (INIS)

    Dussel, G.G.; Maqueda, E.E.; Perazzo, R.P.J.; Evans, J.A.

    1986-01-01

    A model is considered consisting of nucleons moving in two non-degenerate l-shells and interacting through two pairing residual interactions with (S, T) = (1, 0) and (0, 1). These, together with the single particle hamiltonian induce mutually destructive correlations, giving rise to various collective pictures that can be discussed as representing a two-dimensional space of phases. The model is solved exactly using an O(8)xO(8) group theoretical classification scheme. The transfer of correlated pairs and quartets is also discussed. (orig.)

  7. Pumping Electron-Positron Pairs from a Well Potential.

    Science.gov (United States)

    Wang, Qiang; Liu, Jie; Fu, Li-Bin

    2016-04-29

    In the presence of very deep well potential, electrons will spontaneously occupy the empty embedded bound states and electron-positron pairs are created by means of a non-perturbative tunneling process. In this work, by slowly oscillating the width or depth, the population transfer channels are opened and closed periodically. We find and clearly show that by the non-synchronous ejections of particles, the saturation of pair number in a static super-critical well can be broken, and electrons and positrons can be pumped inexhaustibly from vacuum with a constant production rate. In the adiabatic limit, final pair number after a single cycle has quantized values as a function of the upper boundary of the oscillating, and the critical upper boundaries indicate the diving points of the bound states.

  8. Kohn singularity and Kohn anomaly in conventional superconductors—role of pairing mechanism

    International Nuclear Information System (INIS)

    Chaudhury, Ranjan; Das, Mukunda P

    2013-01-01

    We present a theoretical analysis of the Kohn singularity and Kohn anomaly in the superconducting phase of a three-dimensional metallic system. We show that a phonon mechanism-based Cooper pairing in a Fermi liquid metal can lead to these phenomena quite naturally. The results are discussed against the background of some recent experimental findings. (fast track communication)

  9. The telltale face: possible mechanisms behind defector and cooperator recognition revealed by emotional facial expression metrics.

    Science.gov (United States)

    Kovács-Bálint, Zsófia; Bereczkei, Tamás; Hernádi, István

    2013-11-01

    In this study, we investigated the role of facial cues in cooperator and defector recognition. First, a face image database was constructed from pairs of full face portraits of target subjects taken at the moment of decision-making in a prisoner's dilemma game (PDG) and in a preceding neutral task. Image pairs with no deficiencies (n = 67) were standardized for orientation and luminance. Then, confidence in defector and cooperator recognition was tested with image rating in a different group of lay judges (n = 62). Results indicate that (1) defectors were better recognized (58% vs. 47%), (2) they looked different from cooperators (p towards the cooperator category (p < .01), and (4) females were more confident in detecting defectors (p < .05). According to facial microexpression analysis, defection was strongly linked with depressed lower lips and less opened eyes. Significant correlation was found between the intensity of micromimics and the rating of images in the cooperator-defector dimension. In summary, facial expressions can be considered as reliable indicators of momentary social dispositions in the PDG. Females may exhibit an evolutionary-based overestimation bias to detecting social visual cues of the defector face. © 2012 The British Psychological Society.

  10. Multi-nucleon transfer: a probe to investigate the reaction mechanism around the barrier

    International Nuclear Information System (INIS)

    Mandal, Samit K.

    2014-01-01

    The investigation of multi-nucleon transfer mechanism offers valuable information on the pairing interactions that enhance the transfer of nucleon pairs across heavy ions involved in the reaction. These reactions are also a useful tool to study exotic nuclei far from the stability line, which can be explored with the new generation radioactive beam facility. In this talk, multi-nucleon transfer reaction mechanisms between heavy ions and their effect on the reaction dynamics around the coulomb barrier energies have been discussed. Experimental results will be presented with a semi classical description of multi nucleon transfer reaction calculation. One and two nucleon transfer cross sections reproduced using a quantum mechanical coupled channel calculations will also be discussed. A feasibility of investigation of multi-nucleon transfer mechanism to explore the pairing correlation at moderate spin states with radioactive beams will be discussed. (author)

  11. A Project in Support of International Nuclear Cooperation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myung Ro; Kim, Kyoung Pyo; Lee, Jeong Kong; Jung, Sung Hyon; Shim, Jae Sun

    2008-12-15

    The objective of this study is to establish the strategies of international cooperation in order to promote our nation's leading role in international community, to lay the foundation for the effective transfer of nuclear technology to developing countries, and to cope with the rapidly changing in the international nuclear communities. This study contains the work undertaken to promote multilateral cooperation within the framework of international nuclear related organizations and regional cooperative agreements and the relevant forums, to enhance bilateral cooperation with foreign nuclear related research institutes as well as to promote cooperation through the exchange of foreign scientists. As for multilateral cooperation, activities for promoting cooperation within the IAEA and regional cooperative frameworks are introduced. Regarding bilateral cooperation, activities for concluding arrangements and MOUs with foreign research institutes and for participation in joint nuclear coordinating committee meetings between Korea and other countries are presented. For promoting personnel exchanges, activities for inviting and utilizing foreign scientists and mutual discussions with foreign experts, who have visited KAERI, are also described. Continuous efforts to contributing towards the international community through utilizing Korea's experience gained in the process of technical self-reliance and development of human resources are needed. Also efforts to establish the foundation of international cooperation and to make inroad into overseas nuclear markets for export of our nuclear technologies should be made. Meanwhile in the bilateral cooperation, we need to beef up cooperation with U.S.A. and Canada through the joint committee for the joint export to third countries. It is expected that this study would be utilized as a basic material for the international cooperation of nuclear energy, especially for the KAERI's international cooperation in an

  12. A Project in Support of International Nuclear Cooperation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myung Ro; Kim, Kyoung Pyo; Lee, Jeong Kong; Jung, Sung Hyon; Shim, Jae Sun

    2009-01-15

    The objective of this study is to establish the strategies of international cooperation in order to promote our nation's leading role in international community, to lay the foundation for the effective transfer of nuclear technology to developing countries, and to cope with the rapidly changing in the international nuclear communities. This study contains the work undertaken to promote multilateral cooperation within the framework of international nuclear related organizations and regional cooperative agreements and the relevant forums, to enhance bilateral cooperation with foreign nuclear related research institutes as well as to promote cooperation through the exchange of foreign scientists. As for multilateral cooperation, activities for promoting cooperation within the IAEA and regional cooperative frameworks are introduced. Regarding bilateral cooperation, activities for concluding arrangements and MOUs with foreign research institutes and for participation in joint nuclear coordinating committee meetings between Korea and other countries are presented. For promoting personnel exchanges, activities for inviting and utilizing foreign scientists and mutual discussions with foreign experts, who have visited KAERI, are also described. Continuous efforts to contributing towards the international community through utilizing Korea's experience gained in the process of technical self-reliance and development of human resources are needed. Also efforts to establish the foundation of international cooperation and to make inroad into overseas nuclear markets for export of our nuclear technologies should be made. Meanwhile in the bilateral cooperation, we need to beef up cooperation with U.S.A. and Canada through the joint committee for the joint export to third countries. It is expected that this study would be utilized as a basic material for the international cooperation of nuclear energy, especially for the KAERI's international cooperation in an

  13. Effect of single-particle splitting in the exact wave function of the isovectorial pairing Hamiltonian

    International Nuclear Information System (INIS)

    Lerma H, S.

    2010-01-01

    The structure of the exact wave function of the isovectorial pairing Hamiltonian with nondegenerate single-particle levels is discussed. The way that the single-particle splittings break the quartet condensate solution found for N=Z nuclei in a single degenerate level is established. After a brief review of the exact solution, the structure of the wave function is analyzed and some particular cases are considered where a clear interpretation of the wave function emerges. An expression for the exact wave function in terms of the isospin triplet of pair creators is given. The ground-state wave function is analyzed as a function of pairing strength, for a system of four protons and four neutrons. For small and large values of the pairing strength a dominance of two-pair (quartets) scalar couplings is found, whereas for intermediate values enhancements of the nonscalar couplings are obtained. A correlation of these enhancements with the creation of Cooper-like pairs is observed.

  14. Vinylimidazole-Based Asymmetric Ion Pair Comonomers: Synthesis, Polymerization Studies and Formation of Ionically Crosslinked PMMA

    NARCIS (Netherlands)

    Jana, S.; Vasantha, V.A.; Stubbs, L.P.; Parthiban, A.; Vancso, Gyula J.

    2013-01-01

    Vinylimidazole-based asymmetric ion pair comonomers (IPCs) which are free from nonpolymerizable counter ions have been synthesized, characterized and polymerized by free radical polymerization (FRP), atom transfer radical polymerization (ATRP), and reversible addition-fragmentation chain transfer

  15. Organizational choices for international cooperation: East-West European cooperation on regional environmental problems

    Science.gov (United States)

    Connolly, Barbara Mary

    This dissertation applies theoretical insights from transaction cost economics to explain and predict the organizational form of cooperative agreements between Eastern and Western Europe in areas of regional environmental and political concern. It examines five contracting problems related to nuclear power safety and acid rain, and describes the history of international negotiations to manage these problems. It argues that the level of interdependence in a given issue area, or costly effects experienced in one state due to activities and decisions of other states, along with the level of transactional vulnerability, or sunk costs invested in support of a particular contractual relationship among these states, are key determinants of the governance structures states choose to facilitate cooperation in that issue area. Empirically, the dissertation traces the evolution of three sets of institutional arrangements related to nuclear safety: governance for western nuclear safety assistance to Eastern Europe, negotiations of a global convention on safety standards for nuclear power plants, and contracts among utilities and multilateral banks to build new nuclear power plants in Eastern Europe. Next it studies European acid rain, chronicling the history of international acid rain controls within the UNECE Convention on Long-Range Transboundary Air Pollution (LRTAP) and the European Union, and finally examining institutional arrangements for burden-sharing to promote European bargains on emissions reduction, including bilateral aid transfers and proposals for multilateral burden sharing. Political actors have a wide range of choice among institutional arrangements to facilitate international cooperation, from simple market-type exchanges, to arbitration-type regimes that provide information and enhance reputation effects, to self-enforcing agreements such as issue-linkage, to supranational governance. The governance structures states devise to manage their cooperative

  16. HASIL BELAJAR DAN PEMBELAJARAN KOOPERATIF TIPE THINK PAIR SHARE (TPS

    Directory of Open Access Journals (Sweden)

    Loli Jasdilla

    2017-03-01

    Full Text Available The objectives of this research is to improve social science outcomes by using Think Pair Share (TPS for the fourth grade in elementary school. This research is classroom action research. The procedure of this research conducted planning, acting, observation, and reflection. Subject of this research was 22 students for the fourth grade in SD 20 Kalumbuk, Padang. Techniques of collecting data were using test and observation. Data analyzed by using thematic analysis. Data validated by using triangulation, member checking, and reflecivity. The students’ learning outcomes improved from 76,75% into 89,67% (very good. The result of this research shows that cooperative model of Think Pair Share (TPS type can improve social science outcomes for the fourth grade students of elementary school.

  17. A Novel Optimal Joint Resource Allocation Method in Cooperative Multicarrier Networks: Theory and Practice

    Directory of Open Access Journals (Sweden)

    Yuan Gao

    2016-04-01

    Full Text Available With the increasing demands for better transmission speed and robust quality of service (QoS, the capacity constrained backhaul gradually becomes a bottleneck in cooperative wireless networks, e.g., in the Internet of Things (IoT scenario in joint processing mode of LTE-Advanced Pro. This paper focuses on resource allocation within capacity constrained backhaul in uplink cooperative wireless networks, where two base stations (BSs equipped with single antennae serve multiple single-antennae users via multi-carrier transmission mode. In this work, we propose a novel cooperative transmission scheme based on compress-and-forward with user pairing to solve the joint mixed integer programming problem. To maximize the system capacity under the limited backhaul, we formulate the joint optimization problem of user sorting, subcarrier mapping and backhaul resource sharing among different pairs (subcarriers for users. A novel robust and efficient centralized algorithm based on alternating optimization strategy and perfect mapping is proposed. Simulations show that our novel method can improve the system capacity significantly under the constraint of the backhaul resource compared with the blind alternatives.

  18. Selective Cooperation in Early Childhood - How to Choose Models and Partners.

    Directory of Open Access Journals (Sweden)

    Jonas Hermes

    Full Text Available Cooperation is essential for human society, and children engage in cooperation from early on. It is unclear, however, how children select their partners for cooperation. We know that children choose selectively whom to learn from (e.g. preferring reliable over unreliable models on a rational basis. The present study investigated whether children (and adults also choose their cooperative partners selectively and what model characteristics they regard as important for cooperative partners and for informants about novel words. Three- and four-year-old children (N = 64 and adults (N = 14 saw contrasting pairs of models differing either in physical strength or in accuracy (in labeling known objects. Participants then performed different tasks (cooperative problem solving and word learning requiring the choice of a partner or informant. Both children and adults chose their cooperative partners selectively. Moreover they showed the same pattern of selective model choice, regarding a wide range of model characteristics as important for cooperation (preferring both the strong and the accurate model for a strength-requiring cooperation tasks, but only prior knowledge as important for word learning (preferring the knowledgeable but not the strong model for word learning tasks. Young children's selective model choice thus reveals an early rational competence: They infer characteristics from past behavior and flexibly consider what characteristics are relevant for certain tasks.

  19. System for selection of radiation source transfer trucks

    International Nuclear Information System (INIS)

    Tanimoto, Yoshinori; Ito, Kojiro.

    1970-01-01

    A device for selection of trucks each of which load and transfer a radiation source to an irradiation room above a water pool is installed at the end of a pair of rails fixed to the bottom of the pool. This device is equipped with a number of laterally shiftable rail pairs which may be brought into successive alignment with the fixed rails and is adapted to receive, carry and fix a truck on each rail pair. If one of said trucks is selected for irradiation in a desired irradiation room, the rail pair carrying this truck is shifted to align and couple with the fixed rail pair whereupon the truck is driven and transferred to a position on the fixed rails below the desired room and elevated thereinto. Accordingly, a plurality of trucks can optionally be shunted on a line of fixed rails without unloading the respective radiation sources. (Ohno, Y.)

  20. Technology transfer 1994

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    This document, Technology Transfer 94, is intended to communicate that there are many opportunities available to US industry and academic institutions to work with DOE and its laboratories and facilities in the vital activity of improving technology transfer to meet national needs. It has seven major sections: Introduction, Technology Transfer Activities, Access to Laboratories and Facilities, Laboratories and Facilities, DOE Office, Technologies, and an Index. Technology Transfer Activities highlights DOE`s recent developments in technology transfer and describes plans for the future. Access to Laboratories and Facilities describes the many avenues for cooperative interaction between DOE laboratories or facilities and industry, academia, and other government agencies. Laboratories and Facilities profiles the DOE laboratories and facilities involved in technology transfer and presents information on their missions, programs, expertise, facilities, and equipment, along with data on whom to contact for additional information on technology transfer. DOE Offices summarizes the major research and development programs within DOE. It also contains information on how to access DOE scientific and technical information. Technologies provides descriptions of some of the new technologies developed at DOE laboratories and facilities.

  1. Realities of technical co-operation in the peaceful uses of nuclear energy

    International Nuclear Information System (INIS)

    Luxo, A.; Villaros, P.; Naudet, G.

    1978-01-01

    The decision to develop the peaceful uses of nuclear energy, especially the generation of electricity, is usually based - particularly in the developing countries - on numerous considerations, mainly of an economic and political nature. Since the resources of nuclear technology are concentrated, relatively speaking, in the advanced countries, the use of nuclear energy by countries that have decided to go nuclear is based on effective co-operation between the exporting and importing countries. The present paper is intended as an additional contribution to consideration of the realities of such co-operation. The authors first mention the specific features of nuclear development, after which they consider, on the basis thereof, the different forms of co-operation required for the transfer of technological knowhow, and the conditions determining the effectiveness of such transfer. This effectiveness is not linked solely to the competence of the personnel concerned or to smooth organizational procedures, but also to decisive socio-psychological factors. Having analysed these factors, the authors examine the salient problems of co-operation arising during the process of nuclear development. Co-operation ever better adapted to the purpose and taking human considerations into account will enable importing countries to acquire the nuclear knowhow that will promote their economic and social development. (author)

  2. International co-operation through scientific and technical nuclear societies

    International Nuclear Information System (INIS)

    Manning Muntzing, L.

    1983-01-01

    As an international organization the American Nuclear Society (ANS) has played an active role in international co-operation of nuclear technology exchange since its establishment in 1954. The ANS has a membership of over 13,000 individuals, of whom approximately 1200 live overseas in forty countries. To carry out the goals of the Society, local sections have been established. Currently the ANS maintains 48 local sections in the United States of America and 8 overseas local sections in Africa, Asia, Europe and South America. The ANS also has formal agreements for co-operation with The Asociacion Argentina de Tecnologia Nuclear (AATN), the Israel Nuclear Society (INS), and the Chinese Nuclear Society (CNS). In 1977 the Japan Atomic Energy Society (JAES), the European Nuclear Society (ENS), and the ANS co-operation in sponsoring the First International Conference on Transfer of Nuclear Technology (ICONTT I) in Tehran, Iran. In 1982, the Second International Conference on Transfer of Nuclear Technology (ICONTT II), Buenos Aires, Argentina, was sponsored through the co-operation of the AATN, the ENS and the ANS. The ANS and its overseas sections sponsor the Pacific Basin Conference approximately every three years to discuss nuclear matters of concern to the countries around the Pacific Ocean. In 1981 the ANS held a Nuclear Technology Exhibit in Beijing, the People's Republic of China. In addition to meetings, the ANS is extensively involved in the co-operative exchange of applied nuclear research information through its publications. Nuclear Technology, a technical journal, is published monthly under joint ownership of the ENS and the ANS. The ANS has been a leader in voluntary standards development since 1958. In its dedication to the co-operation of international nuclear technology the ANS maintains a comprehensive international exchange of nuclear standards

  3. APPLICABILITY OF COOPERATIVE LEARNING TECHNIQUES IN DIFFERENT CLASSROOM CONTEXTS

    Directory of Open Access Journals (Sweden)

    Dr. Issy Yuliasri

    2017-04-01

    Full Text Available This paper is based on the results of pre-test post-test, feedback questionnaire and observation during a community service program entitled ―Training on English Teaching using Cooperative Learning Techniques for Elementary and Junior High School Teachers of Sekolah Alam Arridho Semarang‖. It was an English teaching training program intended to equip the teachers with the knowledge and skills of using the different cooperative learning techniques such as jigsaw, think-pair-share, three-step interview, roundrobin braistorming, three-minute review, numbered heads together, team-pair-solo, circle the sage, dan partners. This program was participated by 8 teachers of different subjects (not only English, but most of them had good mastery of English. The objectives of this program was to improve teachers‘ skills in using the different cooperative learning techniques to vary their teaching, so that students would be more motivated to learn and improve their English skill. Besides, the training also gave the teachers the knowledge and skills to adjust their techniques with the basic competence and learning objectives to be achieved as well as with the teaching materials to be used. This was also done through workshops using cooperative learning techniques, so that the participants had real experiences of using cooperative learning techniques (learning by doing. The participants were also encouraged to explore the applicability of the techniques in their classroom contexts, in different areas of their teaching. This community service program showed very positive results. The pre-test and post-test results showed that before the training program all the participants did not know the nine cooperative techniques to be trained, but after the program they mastered the techniques as shown from the teaching-learning scenarios they developed following the test instructions. In addition, the anonymous questionnaires showed that all the participants

  4. Forms of Cooperative Learning in Language Teaching in Slovenian Language Classes at the Primary School Level

    Directory of Open Access Journals (Sweden)

    Alenka Rot Vrhovec

    2015-09-01

    Full Text Available In the Slovenian language syllabus, teachers are recommended to provide a greater share of group work during class. During types of learning such as cooperative learning in smaller groups or pairs, students actively develop communicative competence. The present article presents a survey that attempted to determine whether teachers from the first to the fifth grade execute cooperative learning in language classes. The purpose of the article is to raise teachers’ awareness and encourage them to design and execute cooperative learning more frequently.

  5. AT base pair anions versus (9-methyl-A)(1-methyl-T) base pair anions.

    Science.gov (United States)

    Radisic, Dunja; Bowen, Kit H; Dabkowska, Iwona; Storoniak, Piotr; Rak, Janusz; Gutowski, Maciej

    2005-05-04

    The anionic base pairs of adenine and thymine, (AT)(-), and 9-methyladenine and 1-methylthymine, (MAMT)(-), have been investigated both theoretically and experimentally in a complementary, synergistic study. Calculations on (AT)(-) found that it had undergone a barrier-free proton transfer (BFPT) similar to that seen in other dimer anion systems and that its structural configuration was neither Watson-Crick (WC) nor Hoogsteen (HS). The vertical detachment energy (VDE) of (AT)(-) was determined by anion photoelectron spectroscopy and found to be in agreement with the VDE value predicted by theory for the BFPT mechanism. An AT pair in DNA is structurally immobilized into the WC configuration, in part, by being bonded to the sugars of the double helix. This circumstance was mimicked by methylating the sites on both A and T where these sugars would have been tied, viz., 9-methyladenine and 1-methylthymine. Calculations found no BFPT in (MAMT)(-) and a resulting (MAMT)(-) configuration that was either HS or WC, with the configurations differing in stability by ca. 2 kcal/mol. The photoelectron spectrum of (MAMT)(-) occurred at a completely different electron binding energy than had (AT)(-). Moreover, the VDE value of (MAMT)(-) was in agreement with that predicted by theory. The configuration of (MAMT)(-) and its lack of electron-induced proton transfer are inter-related. While there may be other pathways for electron-induced DNA alterations, BFPT in the WC/HS configurations of (AT)(-) is not feasible.

  6. AT Base Pair Anions vs. (9-methyl-A)(1-methyl-T) Base Pair Anions

    International Nuclear Information System (INIS)

    Radisic, Dunja; Bowen, Kit H.; Dabkowska, Iwona; Storoniak, Piotr; Rak, Janusz; Gutowski, Maciej S.

    2005-01-01

    The anionic base pairs of adenine and thymine, (AT)-, and 9-methyladenine and 1-methylthymine, (MAMT)-, have been investigated both theoretically and experimentally in a complementary, synergistic study. Calculations on (AT)- found that it had undergone a barrier-free proton transfer (BFPT) similar to that seen in other dimer anion systems and that its structural configuration that was neither Watson-Crick (WC) nor Hoogsteen (HS). The vertical detachment energy (VDE) of (AT)- was determined by anion photoelectron spectroscopy and found to be in agreement with the VDE value predicted by theory for the BFPT mechanism. An AT pair in DNA is structurally immobilized into the WC configuration, in part, by being bonded to the sugars of the double helix. This circumstance was mimicked by methylating the sites on both A and T where these sugars would have been tied, viz., 9-methyladenine and 1-methylthymine. Calculations found no BFPT in (MAMT)- and a resulting (MAMT)- configuration that wa s either HS or WC, with the configurations differing in stability by ca. 2 kcal/mol. The photoelectron spectrum of (MAMT)- occurred at a completely different electron binding energy than had (AT)-. Moreover, the VDE value of (MAMT)- was in agreement with that predicted by theory. The configuration of (MAMT)- and its lack of electron-induced proton transfer are inter-related. While there may be other pathways for electron-induced damage, BFPT in the WC/HS configurations of (AT)- is not feasible

  7. [Under what conditions does G.C Watson-Crick DNA base pair acquire all four configurations characteristic for A.T Watson-Crick DNA base pair?].

    Science.gov (United States)

    Brovarets', O O

    2013-01-01

    At the MP2/6-311++G(2df,pd)//B3LYP/6-311++G(d,p) level of theory it was established for the first time, that the Löwdin's G*.C* DNA base pair formed by the mutagenic tautomers can acquire, as the A-T Watson-Crick DNA base pair, four biologically important configurations, namely: Watson-Crick, reverse Watson-Crick, Hoogsteen and reverse Hoogsteen. This fact demonstrates rather unexpected role of the tautomerisation of the one of the Watson-Crick DNA base pairs, in particular, via double proton transfer: exactly the G.C-->G*.C* tautomerisation allows to overcome steric hindrances for the implementation of the above mentioned configurations. Geometric, electron-topological and energetic properties of the H-bonds that stabilise the studied pairs, as well as the energetic characteristics of the latters are presented.

  8. Molecular Insights into Variable Electron Transfer in Amphibian Cryptochrome

    DEFF Research Database (Denmark)

    Sjulstok, Emil; Lüdemann, Gesa; Kubař, Tomáš

    2018-01-01

    are mutated, radical-pair formation is still observed. In this study, we computationally investigate electron-transfer pathways in the X. laevis cryptochrome DASH by extensively equilibrating a previously established homology model using molecular dynamics simulations and then mutating key amino acids......Cryptochrome proteins are activated by the absorption of blue light, leading to the formation of radical pairs through electron transfer in the active site. Recent experimental studies have shown that once some of the amino acid residues in the active site of Xenopus laevis cryptochrome DASH...... involved in the electron transfer. The electron-transfer pathways are then probed by using tight-binding density-functional theory. We report the alternative electron-transfer pathways resolved at the molecular level and, through comparison of amino acid sequences for cryptochromes from different species...

  9. Principles of cooperation across systems: from human sharing to multicellularity and cancer.

    Science.gov (United States)

    Aktipis, Athena

    2016-01-01

    From cells to societies, several general principles arise again and again that facilitate cooperation and suppress conflict. In this study, I describe three general principles of cooperation and how they operate across systems including human sharing, cooperation in animal and insect societies and the massively large-scale cooperation that occurs in our multicellular bodies. The first principle is that of Walk Away: that cooperation is enhanced when individuals can leave uncooperative partners. The second principle is that resource sharing is often based on the need of the recipient (i.e., need-based transfers) rather than on strict account-keeping. And the last principle is that effective scaling up of cooperation requires increasingly sophisticated and costly cheater suppression mechanisms. By comparing how these principles operate across systems, we can better understand the constraints on cooperation. This can facilitate the discovery of novel ways to enhance cooperation and suppress cheating in its many forms, from social exploitation to cancer.

  10. Joint sub-carrier pairing and resource allocation for cognitive networks with adaptive relaying

    KAUST Repository

    Soury, Hamza; Bader, F.; Shaat, M.; Alouini, Mohamed-Slim

    2013-01-01

    Relayed transmission in a cognitive radio (CR) environment could be used to increase the coverage and capacity of communication system that benefits already from the efficient management of the spectrum developed by CR. Furthermore, there are many types of cooperative communications, including decode-and-forward (DAF) and amplify-and-forward (AAF). In this paper, these techniques are combined in an adaptive mode to benefit from its forwarding advantages; this mode is called adaptive relaying protocol (ARP). Moreover, this work focuses on the joint power allocation in a cognitive radio system in a cooperative mode that operates ARP in multi-carrier mode. The multi-carrier scenario is used in an orthogonal frequency division multiplexing (OFDM) mode, and the problem is formulated to maximize the end-to-end rate by searching the best power allocation at the transmitters. This work includes, besides the ARP model, a sub-carrier pairing strategy that allows the relays to switch to the best sub-carrier pairs to increase the throughput. The optimization problem is formulated and solved under the interference and power budget constraints using the sub-gradient algorithm. The simulation results confirm the efficiency of the proposed adaptive relaying protocol in comparison to other relaying techniques. The results show also the consequence of the choice of the pairing strategy. 2013 Stolojescu-Crisan and Isar; licensee Springer.

  11. Joint sub-carrier pairing and resource allocation for cognitive networks with adaptive relaying

    KAUST Repository

    Soury, Hamza

    2013-11-09

    Relayed transmission in a cognitive radio (CR) environment could be used to increase the coverage and capacity of communication system that benefits already from the efficient management of the spectrum developed by CR. Furthermore, there are many types of cooperative communications, including decode-and-forward (DAF) and amplify-and-forward (AAF). In this paper, these techniques are combined in an adaptive mode to benefit from its forwarding advantages; this mode is called adaptive relaying protocol (ARP). Moreover, this work focuses on the joint power allocation in a cognitive radio system in a cooperative mode that operates ARP in multi-carrier mode. The multi-carrier scenario is used in an orthogonal frequency division multiplexing (OFDM) mode, and the problem is formulated to maximize the end-to-end rate by searching the best power allocation at the transmitters. This work includes, besides the ARP model, a sub-carrier pairing strategy that allows the relays to switch to the best sub-carrier pairs to increase the throughput. The optimization problem is formulated and solved under the interference and power budget constraints using the sub-gradient algorithm. The simulation results confirm the efficiency of the proposed adaptive relaying protocol in comparison to other relaying techniques. The results show also the consequence of the choice of the pairing strategy. 2013 Stolojescu-Crisan and Isar; licensee Springer.

  12. Solvent driving force ensures fast formation of a persistent and well-separated radical pair in plant cryptochrome

    DEFF Research Database (Denmark)

    Lüdemann, Gesa; Solov'yov, Ilia; Kubar, Tomás

    2015-01-01

    upon the electron transfer. This approach allows us to follow the time evolution of the electron transfer in an unbiased fashion and to reveal the molecular driving force which ensures fast electron transfer in cryptochrome guaranteeing formation of a persistent radical pair suitable...

  13. Immune transfer studies in canine allogeneic marrow graft donor-recipient pairs

    International Nuclear Information System (INIS)

    Grosse-Wilde, H.; Krumbacher, K.; Schuening, F.D.; Doxiadis, I.; Mahmoud, H.K.; Emde, C.; Schmidt-Weinmar, A.; Schaefer, U.W.

    1986-01-01

    Transfer of immunity occurring with bone marrow grafting was studied using the dog as a preclinical model. Allogeneic bone marrow transplantation (BMT) was performed between DLA-identical beagle litter-mates. The donors were immunized with tetanus toxoid (TT) or sheep red blood cells (SRBC), and their humoral response was monitored by hemagglutination. The recipients of bone marrow from TT-immunized donors showed a marked increase of antibody titer one week posttransplantation, while in the recipients of marrow from SRBC immunized donors the antibody titers were considerably lower. Within the following 60 days the antibody titers in both groups diminished gradually to pregrafting levels. Control experiments in which cell-free plasma from donors immunized with TT and SRBC respectively was transfused indicated that the initial rise of specific antibody titers after marrow grafting is likely to be due to a passive transfer of humoral immunity. A single challenge of these marrow graft recipients with the respective antigen 15-18 weeks posttransplantation led to a secondary type of humoral immune response. It could be demonstrated that transfer of memory against TT or SRBC was independent from the actual antibody titer and the time of vaccination of the donor. One dog was immunized with TT after serving as marrow donor. When the donor had shown an antibody response, a peripheral blood leukocytes (PBL) transfusion was given to his chimera. Subsequent challenge of the latter resulted in a secondary type of specific antibody response. This indicates that specific cellular-bound immunological memory can be transferred after BMT from the donor to his allogeneic bone marrow chimera by transfusion of peripheral blood leukocytes. The data may be of importance in clinical BMT to protect patients during the phase of reduced immune reactivity by transfer of memory cells

  14. Costly advertising and the evolution of cooperation

    OpenAIRE

    Brede, Markus

    2013-01-01

    In this paper, I investigate the co-evolution of fast and slow strategy spread and game strategies in populations of spatially distributed agents engaged in a one off evolutionary dilemma game. Agents are characterized by a pair of traits, a game strategy (cooperate or defect) and a binary 'advertising' strategy (advertise or don't advertise). Advertising, which comes at a cost [Formula: see text], allows investment into faster propagation of the agents' traits to adjacent individuals. Import...

  15. A heat transfer textbook

    CERN Document Server

    Lienhard, John H

    2011-01-01

    This introduction to heat transfer offers advanced undergraduate and graduate engineering students a solid foundation in the subjects of conduction, convection, radiation, and phase-change, in addition to the related topic of mass transfer. A staple of engineering courses around the world for more than three decades, it has been revised and updated regularly by the authors, a pair of recognized experts in the field. The text addresses the implications, limitations, and meanings of many aspects of heat transfer, connecting the subject to its real-world applications and developing students' ins

  16. International Cooperation and Knowledge Transfer Processes / La cooperación internacional y los procesos de transferencia del conocimiento

    Directory of Open Access Journals (Sweden)

    Wilson López López

    2013-03-01

    already been created. Surely the platform will continue its consolidation and will enable the maximisation of cooperation processes.We hope that groups use this tool to share documents, discuss and create synergies that lead them to collaborate and transfer knowledge. We will also be linking Open Source systems in the portal, such as Redalyc, SciELO, Pepsic, the Psychology Virtual Library and free citation statistics websites such as Google Scholar, Scimago Journal and Country Rank, and also commercial systems such as WoS JCR. Researchers use these and other systems to find knowledge usage information, which they can use in turn to increase cooperation. It is clear that one of the biggest challenges of our regional Psychology is that the visibility of Open Access is reflected in its use. We also understand that we need to develop new ways of measuring this use and of getting cooperation to become a critical source of this process. We hope that tools such as the one we just presented fit into this perspective.

  17. Chiral Selectivity in Inter-reactant Recognition and Electron Transfer of the Oxidation of Horse Heart Cytochrome c by Trioxalatocobaltate(III)

    DEFF Research Database (Denmark)

    Nazmutdinov, Renat R.; Bronshtein, Michael D.; Zinkicheva, Tamara T.

    2016-01-01

    We have studied electron transfer between cytochrome c and the chiral transition-metal complex pair Λ- and Δ-[Co(Ox)3]3− (Ox2− = oxalate) via strong ion-pair formation. Chirality was found in both ion-pair formation and electron transfer, with the Λ enantiomer the more strongly bound and faster r...... reacting. Investigations of the chirality using electron-transfer theory combined with quantum-chemical and statistical-mechanical calculations showed that chirality is solely in inter-reactant interaction and electronic overlap.......We have studied electron transfer between cytochrome c and the chiral transition-metal complex pair Λ- and Δ-[Co(Ox)3]3− (Ox2− = oxalate) via strong ion-pair formation. Chirality was found in both ion-pair formation and electron transfer, with the Λ enantiomer the more strongly bound and faster...

  18. Paternity of subordinates raises cooperative effort in cichlids.

    Directory of Open Access Journals (Sweden)

    Rick Bruintjes

    Full Text Available In cooperative breeders, subordinates generally help a dominant breeding pair to raise offspring. Parentage studies have shown that in several species subordinates can participate in reproduction. This suggests an important role of direct fitness benefits for cooperation, particularly where groups contain unrelated subordinates. In this situation parentage should influence levels of cooperation. Here we combine parentage analyses and detailed behavioural observations in the field to study whether in the highly social cichlid Neolamprologus pulcher subordinates participate in reproduction and if so, whether and how this affects their cooperative care, controlling for the effect of kinship.We show that: (i male subordinates gained paternity in 27.8% of all clutches and (ii if they participated in reproduction, they sired on average 11.8% of young. Subordinate males sharing in reproduction showed more defence against experimentally presented egg predators compared to subordinates not participating in reproduction, and they tended to stay closer to the breeding shelter. No effects of relatedness between subordinates and dominants (to mid-parent, dominant female or dominant male were detected on parentage and on helping behaviour.This is the first evidence in a cooperatively breeding fish species that the helping effort of male subordinates may depend on obtained paternity, which stresses the need to consider direct fitness benefits in evolutionary studies of helping behaviour.

  19. Co-operation and Phase Behavior under the Mixed Updating Rules

    International Nuclear Information System (INIS)

    Zhang Wen; Li Yao-Sheng; Xu Chen

    2015-01-01

    We present a model by considering two updating rules when the agents play prisoner's dilemma on a square lattice. Agents can update their strategies by referencing one of his neighbors of higher payoffs under the imitation updating rule or directly replaced by one of his neighbors according to the death-birth updating rule. The frequency of co-operation is related to the probability q of occurrence of the imitation updating or the death-birth updating and the game parameter b. The death-birth updating rule favors the co-operation while the imitation updating rule favors the defection on the lattice, although both rules suppress the co-operation in the well-mixed population. Therefore a totally co-operative state may emerge when the death-birth updating is involved in the evolution when b is relatively small. We also obtain a phase diagram on the q-b plane. There are three phases on the plane with two pure phases of a totally co-operative state and a totally defective state and a mixing phase of mixed strategies. Based on the pair approximation, we theoretically analyze the phase behavior and obtain a quantitative agreement with the simulation results. (paper)

  20. Asian regional co-operative project on food irradiation: Technology transfer

    International Nuclear Information System (INIS)

    1992-01-01

    These Proceedings include the final reports of work performed by different institutions under the scope of Phase II of the Asian Regional Co-operative Project on Food Irradiation. The topics covered include the disinfestation and decontamination of stored products; improvements in the hygiene of processed seafood; insect disinfestation of fruits; and sprout inhibition of root crops. The individual presentations are indexed separately. Refs, figs and tabs

  1. Short versus long term benefits and the evolution of cooperation in the prisoner's dilemma game.

    Directory of Open Access Journals (Sweden)

    Markus Brede

    Full Text Available In this paper I investigate the evolution of cooperation in the prisoner's dilemma when individuals change their strategies subject to performance evaluation of their neighbours over variable time horizons. In the monochrome setting, in which all agents per default share the same performance evaluation rule, weighing past events strongly dramatically enhances the prevalence of cooperators. For co-evolutionary models, in which evaluation time horizons and strategies can co-evolve, I demonstrate that cooperation naturally associates with long-term evaluation of others while defection is typically paired with very short time horizons. Moreover, considering the continuous spectrum in between enhanced and discounted weights of past performance, cooperation is optimally supported when cooperators neither give enhanced weight to past nor more recent events, but simply average payoffs. Payoff averaging is also found to emerge as the dominant strategy for cooperators in co-evolutionary models, thus proposing a natural route to the evolution of cooperation in viscous populations.

  2. Highly Efficient Cooperative Catalysis by Co III (Porphyrin) Pairs in Interpenetrating Metal-Organic Frameworks

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Zekai; Zhang, Zhi-Ming; Chen, Yu-Sheng; Lin, Wenbin (UC); (Xiamen)

    2016-12-02

    A series of porous twofold interpenetrated In-CoIII(porphyrin) metal–organic frameworks (MOFs) were constructed by in situ metalation of porphyrin bridging ligands and used as efficient cooperative catalysts for the hydration of terminal alkynes. The twofold interpenetrating structure brings adjacent CoIII(porphyrins) in the two networks parallel to each other with a distance of about 8.8 Å, an ideal distance for the simultaneous activation of both substrates in alkyne hydration reactions. As a result, the In-CoIII(porphyrin) MOFs exhibit much higher (up to 38 times) catalytic activity than either homogeneous catalysts or MOF controls with isolated CoIII(porphyrin) centers, thus highlighting the potential application of MOFs in cooperative catalysis.

  3. Recoil effects in multiphoton electron-positron pair creation

    International Nuclear Information System (INIS)

    Krajewska, K.; Kaminski, J. Z.

    2010-01-01

    Triply differential probability rates for electron-positron pair creation in laser-nucleus collisions, calculated within the S-matrix approach, are investigated as functions of the nuclear recoil. Pronounced enhancements of differential probability rates of multiphoton pair production are found for a nonzero momentum transfer from the colliding nucleus. The corresponding rates show a very dramatic dependence on the polarization of the laser field impinging on the nucleus; only for a linearly polarized light are the multiphoton rates for electron-positron pair production considerably large. We focus therefore on this case. Our numerical results for different geometries of the reaction particles demonstrate that, for the linearly polarized laser field of an infinite extent (which is a good approximation for femtosecond laser pulses), the pair creation is far more efficient if the nucleus is detected in the direction of the laser-field propagation. The corresponding angular distributions of the created particles show that the high-energy pairs are predominantly produced in the plane spanned by the polarization vector and the laser-field propagation direction, while the low-energy pairs are rather spread around the latter of the two directions. The enhancement of differential probability rates at each energy sector, defined by the four-momentum conservation relation, is observed with varying the energy of the produced particles. The total probability rates of pair production are also evaluated and compared with the corresponding results for the case when one disregards the recoil effect. A tremendous enhancement of the total probability rates of the electron-positron pair creation is observed if one takes into account the nuclear recoil.

  4. Observation of water separated ion-pairs between cations and phospholipid headgroups.

    Science.gov (United States)

    van der Post, Sietse T; Hunger, Johannes; Bonn, Mischa; Bakker, Huib J

    2014-04-24

    In this work, we present evidence for ion pair formation of cations with a high surface charge density (Na(+) and Ca(2+)) and phosphate groups of phospholipids. We used femto-second infrared pump-probe and dielectric spectroscopy to probe the dynamics of water molecules in solutions of phosphorylethanolamine and different types of cations. We find that sodium and calcium cooperatively retard the dynamics of water in solutions of phosphorylethanolamine, implying the formation of solvent separated ion pairs. This ion-specific interaction is absent for potassium, cesium and ammonium. We compare our results to dielectric spectroscopy experiments, which probes the rotation of all dipolar molecules and ions in solution. The rotation of the dipolar phosphorylethanolamine ion shows that long-lived ion-pairs are only formed with calcium and not with ammonium, cesium, potassium, and sodium. This finding implies that the association between calcium and the phosphate is strong with lifetimes exceeding 200 ps, while the interaction with sodium is relatively short-lived (∼20-100 ps).

  5. Transfer of tactile perceptual learning to untrained neighboring fingers reflects natural use relationships.

    Science.gov (United States)

    Dempsey-Jones, Harriet; Harrar, Vanessa; Oliver, Jonathan; Johansen-Berg, Heidi; Spence, Charles; Makin, Tamar R

    2016-03-01

    Tactile learning transfers from trained to untrained fingers in a pattern that reflects overlap between the representations of fingers in the somatosensory system (e.g., neurons with multifinger receptive fields). While physical proximity on the body is known to determine the topography of somatosensory representations, tactile coactivation is also an established organizing principle of somatosensory topography. In this study we investigated whether tactile coactivation, induced by habitual inter-finger cooperative use (use pattern), shapes inter-finger overlap. To this end, we used psychophysics to compare the transfer of tactile learning from the middle finger to its adjacent fingers. This allowed us to compare transfer to two fingers that are both physically and cortically adjacent to the middle finger but have differing use patterns. Specifically, the middle finger is used more frequently with the ring than with the index finger. We predicted this should lead to greater representational overlap between the former than the latter pair. Furthermore, this difference in overlap should be reflected in differential learning transfer from the middle to index vs. ring fingers. Subsequently, we predicted temporary learning-related changes in the middle finger's representation (e.g., cortical magnification) would cause transient interference in perceptual thresholds of the ring, but not the index, finger. Supporting this, longitudinal analysis revealed a divergence where learning transfer was fast to the index finger but relatively delayed to the ring finger. Our results support the theory that tactile coactivation patterns between digits affect their topographic relationships. Our findings emphasize how action shapes perception and somatosensory organization. Copyright © 2016 the American Physiological Society.

  6. ENHANCING STUDENTS‟ MOTIVATION AND ACHIEVEMENT IN LEARNING GRAMMAR THROUGH CONTEXTUAL TEACHING AND LEARNING THROUGH RELATING, EXPERIENCING, APPLYING, COOPERATING AND TRANSFERRING (REACT STRATEGY

    Directory of Open Access Journals (Sweden)

    Mashlihatul Umami Umami

    2017-04-01

    Full Text Available This research addresses the issue of whether Contextual Teaching and Learning (CTL through REACT (Relating, Experiencing, Applying, Cooperating and Transferring strategy is able to enhance motivation and achievement of English Department students‘ in learning grammar. The researcher uses a classroom action research in which it was held for about two cycles. The instruments of collecting the data are observation, rubric, questionaire and test. The researcher analyzes the data using three steps, i.e. students‘ motivation to learn are analyzed by the sheet of observation, each of individuals is also analyzed by fulfilling the questionnaire of self assessment, the progress of students‘ motivation and achievement are all monitored by rubric assessment tool, seven components of REACT strategy in learning is also recorded by the sheets of observation and the statistical analysis using t-test measures the improvement occurred. In addition, the researcher prepares field note and questionnaire to monitor the process of learning. Based on the results of qualitative-quantitative analysis, it can be found that the use of CTL approach especially using project based and cooperative learning improves the students‘ motivation and achievement in learning grammar.

  7. Global Organization of Innovation and Cooperability in Brazilian Multinationals

    Directory of Open Access Journals (Sweden)

    Priscila Rezende da Costa

    2017-04-01

    Full Text Available Understanding the dissipation of innovations is necessary to develop them, as a company on its own does not have all the capabilities that it needs. On the contrary, they are increasingly spread over internal and external contexts, and are not developed in isolation. Most of the time, they depend on interactive, innovative processes in a global context. The aim of this study is to evaluate how the global organizational structure of innovation affects the dynamic capability of cooperation (cooperability in Brazilian multinationals (BMNs. To achieve this goal, we conducted a survey of BMNs, and a final sample of 60 companies answered a structured questionnaire. We performed statistical tests such as Factor Analysis, Cronbach's Alpha, Multiple Regression and Hierarchical Cluster, and cross-analysis of quantitative results that enabled us to create a Cooperability Model, that is, a model of local, international and global development for a dynamic capability of cooperation in BMNs. The results show that technological strengths of foreign subsidiaries and the reverse transfer of their capabilities to the parent company and technology partners affect the dynamics of cooperation in BMNs (inputs and results of cooperability. Furthermore, we detected an inverse relationship between the autonomy of foreign subsidiaries and the dynamic of cooperation in BMNs.

  8. PENERAPAN MODEL PEMBELAJARAN KOOPERATIF TIPE PAIR CHECKS PEMECAHAN MASALAH UNTUK MENINGKATKAN SOCIAL SKILL SISWA

    Directory of Open Access Journals (Sweden)

    R. Lestari

    2012-07-01

    Full Text Available Tujuan penelitian tindakan kelas ini untuk mengetahui pengaruh proses pembelajaran dengan menggunakan model pembelajaran kooperatif tipe Pair Checks pemecahan masalah terhadap peningkatan social skill siswa. Pada proses penerapan model pembelajaran kooperatif tipe Pair Checks pemecahan masalah siswa dibagi dalam kelompok-kelompok dan satu kelompok terdiri dari dua orang. Setiap kelompok berdiskusi untuk menyelesaikan suatu masalah, kemudian hasil diskusi kelompok akan dicek oleh pasangan dari kelompok lain. Metode Penelitian yang digunakan adalah penelitian tindakan kelas yang dilaksanakan dua siklus. Metode pengumpulan data menggunakan tes dan angket skala sikap, sedangkan teknik analisis data menggunakan teknik analisis data kuantitatif. Social Skill siswa dari siklus I ke siklus II mengalami peningkatan. Hal ini didapatkan dari data angket skala sikap siklus I ke siklus II ketuntasan klasikalnya meningkat dan sebagian besar siswa sudah memiliki social skill yang baik. Hasil belajar kognitif siswa juga mengalami peningkatan. Model pembelajaran kooperatif tipe Pair Checks pemecahan masalah dapat meningkatkan social skill siswa.This two cycles-action research aimed to know learning process applying cooperative learning model-pair checks problem solving type and improvement of student’s social skills. The process of the model was as follows: deviding students into some groups consisting of two students, solving problem by each group and checking result of the discussion by other groups. Data collection method used was test and the use of attitude scale questionnaire, while technique of data analysis used was quantitative data analysis technique. The data analysis result showed that there was an increase of student’s social skill and students’ achievement from cycle one to two. It is concluded that cooperative learning model-pair checks problem solving type can enhance student’s social skills

  9. When Triple Helix Unravels: A Multi-Case Analysis of Failures in Industry-University Cooperative Research Centres

    Science.gov (United States)

    Gray, Denis; Sundstrom, Eric; Tornatzky, Louis G.; McGowen, Lindsey

    2011-01-01

    Cooperative research centres (CRCs) increasingly foster Triple Helix (industry-university-government) collaboration and represent significant vehicles for cooperation across sectors, the promotion of knowledge and technology transfer and ultimately the acceleration of innovation. A growing social science literature on CRCs focuses on their…

  10. Quantitative and Qualitative Results: Cooperative Learning Implementation with Hispanic Community College Freshmen

    Science.gov (United States)

    Morgan, Bobbette M.; Keitz, Ruth A.; Wells, Lori

    2013-01-01

    Five classes of Art Appreciation first semester undergraduate Hispanic students assigned to one professor were selected to experience cooperative learning over a full semester. Pre-semester surveys and post-semester surveys were completed by 104 Hispanic freshmen college students. Strategies used in the classes included Think-Pair-Share, Ticket…

  11. Informal Cooperative Learning in Small Groups: The Effect of Scaffolding on Participation

    Science.gov (United States)

    Lange, Christopher; Costley, Jamie; Han, Seung Lock

    2016-01-01

    This study examines the effect of group work scaffolding on participation. The procedural scaffolding of two cooperative learning techniques, Numbered Heads Together and Think-Pair-Share, are compared based on levels of participation, learning, and satisfaction they elicit. Aspects of participation that are examined include levels of group…

  12. Pairing and low temperature properties of 2 D Fermi-systems with attraction between particles

    International Nuclear Information System (INIS)

    Gorbar, E.V.; Gusynin, V.P.; Loktev, V.M.

    1992-01-01

    Proceeding from microscopic model Hamiltonian for the system of Fermi-particles with attraction the effective Lagrangian, admitting the analysis of its superconducting properties at arbitrary fermion concentration, is obtained.Exact solution for gap and chemical potential makes it possible to trace from local pair situation to Cooper pairing. The crucial parameter discriminating between the regions of exotic and normal superconducting behaviour is show to be that of the energy of the bound fermion state, which, however, rapidly disappears with fermion density increasing. The solutions of the equations for the case of finite temperatures are analysed. (author). 42 refs

  13. Social Value Induction and Cooperation in the Centipede Game.

    Directory of Open Access Journals (Sweden)

    Briony D Pulford

    Full Text Available The Centipede game provides a dynamic model of cooperation and competition in repeated dyadic interactions. Two experiments investigated psychological factors driving cooperation in 20 rounds of a Centipede game with significant monetary incentives and anonymous and random re-pairing of players after every round. The main purpose of the research was to determine whether the pattern of strategic choices observed when no specific social value orientation is experimentally induced--the standard condition in all previous investigations of behavior in the Centipede and most other experimental games--is essentially individualistic, the orthodox game-theoretic assumption being that players are individualistically motivated in the absence of any specific motivational induction. Participants in whom no specific state social value orientation was induced exhibited moderately non-cooperative play that differed significantly from the pattern found when an individualistic orientation was induced. In both experiments, the neutral treatment condition, in which no orientation was induced, elicited competitive behavior resembling behavior in the condition in which a competitive orientation was explicitly induced. Trait social value orientation, measured with a questionnaire, influenced cooperation differently depending on the experimentally induced state social value orientation. Cooperative trait social value orientation was a significant predictor of cooperation and, to a lesser degree, experimentally induced competitive orientation was a significant predictor of non-cooperation. The experimental results imply that the standard assumption of individualistic motivation in experimental games may not be valid, and that the results of such investigations need to take into account the possibility that players are competitively motivated.

  14. Determining the reaction in kinematic pairs of certain mechanisms using a digital computer

    Energy Technology Data Exchange (ETDEWEB)

    Chifchieva, V N

    1980-01-01

    In Dorr classifiers, walking excavators, conveyors, sieves and other mechanisms, one finds a triad with a sliding pair. An algorithm is proposed for determining reactions in the kinematic connections of a triad with one, two or three sliding pairs. The algorithm is suitable for use in digital computers. It is based on the transfer function method, and has several advantages over the technnique of determining reactions in kinematic pairs of V. Zinovyev. A concrete example is given of calculating reactions in the connections of a crank and lever mechanism of a walking excavator.

  15. Synchrony and Physiological Arousal Increase Cohesion and Cooperation in Large Naturalistic Groups.

    Science.gov (United States)

    Jackson, Joshua Conrad; Jong, Jonathan; Bilkey, David; Whitehouse, Harvey; Zollmann, Stefanie; McNaughton, Craig; Halberstadt, Jamin

    2018-01-09

    Separate research streams have identified synchrony and arousal as two factors that might contribute to the effects of human rituals on social cohesion and cooperation. But no research has manipulated these variables in the field to investigate their causal - and potentially interactive - effects on prosocial behaviour. Across four experimental sessions involving large samples of strangers, we manipulated the synchronous and physiologically arousing affordances of a group marching task within a sports stadium. We observed participants' subsequent movement, grouping, and cooperation via a camera hidden in the stadium's roof. Synchrony and arousal both showed main effects, predicting larger groups, tighter clustering, and more cooperative behaviour in a free-rider dilemma. Synchrony and arousal also interacted on measures of clustering and cooperation such that synchrony only encouraged closer clustering-and encouraged greater cooperation-when paired with physiological arousal. The research helps us understand why synchrony and arousal often co-occur in rituals around the world. It also represents the first use of real-time spatial tracking as a precise and naturalistic method of simulating collective rituals.

  16. Multi-pair states in electron–positron pair creation

    Directory of Open Access Journals (Sweden)

    Anton Wöllert

    2016-09-01

    Full Text Available Ultra strong electromagnetic fields can lead to spontaneous creation of single or multiple electron–positron pairs. A quantum field theoretical treatment of the pair creation process combined with numerical methods provides a description of the fermionic quantum field state, from which all observables of the multiple electron–positron pairs can be inferred. This allows to study the complex multi-particle dynamics of electron–positron pair creation in-depth, including multi-pair statistics as well as momentum distributions and spin. To illustrate the potential benefit of this approach, it is applied to the intermediate regime of pair creation between nonperturbative Schwinger pair creation and perturbative multiphoton pair creation where the creation of multi-pair states becomes nonnegligible but cascades do not yet set in. Furthermore, it is demonstrated how spin and helicity of the created electrons and positrons are affected by the polarization of the counterpropagating laser fields, which induce the creation of electron–positron pairs.

  17. Multi-pair states in electron–positron pair creation

    Energy Technology Data Exchange (ETDEWEB)

    Wöllert, Anton, E-mail: woellert@mpi-hd.mpg.de; Bauke, Heiko, E-mail: heiko.bauke@mpi-hd.mpg.de; Keitel, Christoph H.

    2016-09-10

    Ultra strong electromagnetic fields can lead to spontaneous creation of single or multiple electron–positron pairs. A quantum field theoretical treatment of the pair creation process combined with numerical methods provides a description of the fermionic quantum field state, from which all observables of the multiple electron–positron pairs can be inferred. This allows to study the complex multi-particle dynamics of electron–positron pair creation in-depth, including multi-pair statistics as well as momentum distributions and spin. To illustrate the potential benefit of this approach, it is applied to the intermediate regime of pair creation between nonperturbative Schwinger pair creation and perturbative multiphoton pair creation where the creation of multi-pair states becomes nonnegligible but cascades do not yet set in. Furthermore, it is demonstrated how spin and helicity of the created electrons and positrons are affected by the polarization of the counterpropagating laser fields, which induce the creation of electron–positron pairs.

  18. Multi-pair states in electron–positron pair creation

    International Nuclear Information System (INIS)

    Wöllert, Anton; Bauke, Heiko; Keitel, Christoph H.

    2016-01-01

    Ultra strong electromagnetic fields can lead to spontaneous creation of single or multiple electron–positron pairs. A quantum field theoretical treatment of the pair creation process combined with numerical methods provides a description of the fermionic quantum field state, from which all observables of the multiple electron–positron pairs can be inferred. This allows to study the complex multi-particle dynamics of electron–positron pair creation in-depth, including multi-pair statistics as well as momentum distributions and spin. To illustrate the potential benefit of this approach, it is applied to the intermediate regime of pair creation between nonperturbative Schwinger pair creation and perturbative multiphoton pair creation where the creation of multi-pair states becomes nonnegligible but cascades do not yet set in. Furthermore, it is demonstrated how spin and helicity of the created electrons and positrons are affected by the polarization of the counterpropagating laser fields, which induce the creation of electron–positron pairs.

  19. Potential US/Canadian cooperative activities in geological disposal of radioactive waste

    International Nuclear Information System (INIS)

    Duguid, J.O.

    1980-03-01

    A joint review meeting between the US and Canada was held on June 19 and 20, 1979 to discuss waste isolation activities in crystalline rocks. The review meeting served the purposes of an initial information transfer and as a mechanism to stimulate thinking for a workshop on US/Canadian cooperative programs which was held on June 21, 1979. The workshop participants divided into working groups to discuss areas of potential cooperation: the Administrative Working Group established protocol for information exchange and cooperative activities; the Geotechnical Working Group selected activities in exploration, field testing, instrumentation and measurement technique development, monitoring, and quality assurance where cooperation would be of benefit to both countries; and the Assessment/Modeling Working Group discussed areas in model development and verification, engineered barriers, radiation effects, hydrologic properties of fractured rocks, waste form leaching, and sorption where cooperation would enhance both the US and Canadian programs

  20. Living with strangers: direct benefits favour non-kin cooperation in a communally nesting bird.

    Science.gov (United States)

    Riehl, Christina

    2011-06-07

    The greater ani (Crotophaga major), a Neotropical cuckoo, exhibits an unusual breeding system in which several socially monogamous pairs lay eggs in a single nest and contribute care to the communal clutch. Cooperative nesting is costly-females compete for reproduction by ejecting each other's eggs-but the potential direct or indirect fitness benefits that might accrue to group members have not been identified. In this study, I used molecular genotyping to quantify patterns of genetic relatedness and individual reproductive success within social groups in a single colour-banded population. Microsatellite analysis of 122 individuals in 49 groups revealed that group members are not genetic relatives. Group size was strongly correlated with individual reproductive success: solitary pairs were extremely rare and never successful, and nests attended by two pairs were significantly more likely to be depredated than were nests attended by three pairs. Egg loss, a consequence of reproductive competition, was greater in large groups and disproportionately affected females that initiated laying. However, early-laying females compensated for egg losses by laying larger clutches, and female group members switched positions in the laying order across nesting attempts. The greater ani, therefore, appears to be one of the few species in which cooperative breeding among unrelated individuals is favoured by direct, shared benefits that outweigh the substantial costs of reproductive competition.

  1. Technology Transfer Policy Applied to the U.S. Army Military History Institute Collection

    National Research Council Canada - National Science Library

    Bell, William

    1998-01-01

    .... This cooperative process is called technology transfer. The main point of the laws is to allow commercial vendors and the organizations of the federal government to enter into cooperative research and development agreements (CRADAs...

  2. Salmon fishing by bears and the dawn of cooperative predation.

    Science.gov (United States)

    Stringham, Stephen F

    2012-11-01

    Although bears are an epitome of solitary predation, black (Ursus americanus) and brown bears (U. arctos) occasionally act in pairs to capture salmon (Onchorynchous spp.). I sought to identify conditions that promote pairing and how this relates to optimal foraging. This study on Alaskan black bears assessed whether each mode of fishing (solo vs. paired) occurs mainly where it is most efficient at harvesting salmon--that is, whether modal group size (1 vs. 2) is also optimal size. Not in this case. Pairing increased captures per attempt (benefit/cost ratio = profitability) by up to 47% and captures per minute by up to 5.2-fold. Yet, the ratio of paired versus solo fishing was significantly lower than either profitability or chance explains. Modal group size was 1, optimal size was 2. This discrepancy did not result from intervention by other current benefits and costs, but from unnecessary defensiveness toward any rapidly approaching conspecific, even though it was chasing salmon, not threatening. For bears to regularly hunt cooperatively, they would have to more readily habituate to agonistic-like predatory actions, communicate intentions from > 10 m apart, and assess situational variations in benefit/cost ratios for solo versus paired hunting. It would be revealing to discover how social carnivores overcame these challenges.

  3. Power corrupts co-operation: cognitive and motivational effects in a double EEG paradigm

    Science.gov (United States)

    Kanso, Riam; Hewstone, Miles; Hawkins, Erin; Waszczuk, Monika; Nobre, Anna Christina

    2014-01-01

    This study investigated the effect of interpersonal power on co-operative performance. We used a paired electro-encephalogram paradigm: pairs of participants performed an attention task, followed by feedback indicating monetary loss or gain on every trial. Participants were randomly allocated to the power-holder, subordinate or neutral group by creating different levels of control over how a joint monetary reward would be allocated. We found that power was associated with reduced behavioural accuracy. Event-related potential analysis showed that power-holders devoted less motivational resources to their targets than did subordinates or neutrals, but did not differ at the level of early conflict detection. Their feedback potential results showed a greater expectation of rewards but reduced subjective magnitude attributed to losses. Subordinates, on the other hand, were asymmetrically sensitive to power-holders’ targets. They expected fewer rewards, but attributed greater significance to losses. Our study shows that power corrupts balanced co-operation with subordinates. PMID:23160813

  4. Power corrupts co-operation: cognitive and motivational effects in a double EEG paradigm.

    Science.gov (United States)

    Kanso, Riam; Hewstone, Miles; Hawkins, Erin; Waszczuk, Monika; Nobre, Anna Christina

    2014-02-01

    This study investigated the effect of interpersonal power on co-operative performance. We used a paired electro-encephalogram paradigm: pairs of participants performed an attention task, followed by feedback indicating monetary loss or gain on every trial. Participants were randomly allocated to the power-holder, subordinate or neutral group by creating different levels of control over how a joint monetary reward would be allocated. We found that power was associated with reduced behavioural accuracy. Event-related potential analysis showed that power-holders devoted less motivational resources to their targets than did subordinates or neutrals, but did not differ at the level of early conflict detection. Their feedback potential results showed a greater expectation of rewards but reduced subjective magnitude attributed to losses. Subordinates, on the other hand, were asymmetrically sensitive to power-holders' targets. They expected fewer rewards, but attributed greater significance to losses. Our study shows that power corrupts balanced co-operation with subordinates.

  5. In vivo dynamics of enterovirus protease revealed by fluorescence resonance emission transfer (FRET) based on a novel FRET pair

    International Nuclear Information System (INIS)

    Hsu, Y.-Y.; Liu, Y.-N.; Wang Wenyen; Kao, Fu-Jen; Kung, S.-H.

    2007-01-01

    An in vivo protease assay suitable for analysis by fluorescence resonance energy transfer (FRET) was developed on the basis of a novel FRET pair. The specifically designed fusion substrate consists of green fluorescent protein 2 (GFP 2 )-peptide-red fluorescent protein 2 (DsRed2), with a cleavage motif for the enterovirus 2A protease (2A pro ) embedded within the peptide region. FRET can be readily visualized in real-time from cells expressing the fusion substrate until a proteolytic cleavage by 2A pro from the input virus. The level of FRET decay is a function of the amount and infection duration of the inoculated virus as measured by a fluorometer assay. The FRET biosensor also responded well to other related enteroviruses but not to a phylogenetically distant virus. Western blot analysis confirmed the physical cleavage of the fusion substrate upon the infections. The study provides proof of principle for applying the FRET technology to diagnostics, screening procedures, and cell biological research

  6. Envisaging quantum transport phenomenon in a muddled base pair of DNA

    Science.gov (United States)

    Vohra, Rajan; Sawhney, Ravinder Singh

    2018-05-01

    The effect of muddled base pair on electron transfer through a deoxyribonucleic acid (DNA) molecule connected to the gold electrodes has been elucidated using tight binding model. The effect of hydrogen and nitrogen bonds on the resistance of the base pair has been minutely observed. Using the semiempirical extended Huckel approach within NEGF regime, we have determined the current and conductance vs. bias voltage for disordered base pairs of DNA made of thymine (T) and adenine (A). The asymmetrical behaviour amid five times depreciation in the current characteristics has been observed for deviated Au-AT base pair-Au devices. An interesting revelation is that the conductance of the intrinsic AT base pair configuration attains dramatically high values with the symmetrical zig-zag pattern of current, which clearly indicates the transformation of the bond length within the strands of base pair when compared with other samples. A thorough investigation of the transmission coefficients T( E) and HOMO-LUMO gap reveals the misalignment of the strands in base pairs of DNA. The observed results present an insight to extend this work to build biosensing devices to predict the abnormality with the DNA.

  7. Space Station - Opportunity for international cooperation and utilization

    Science.gov (United States)

    Pedersen, K. S.

    1984-01-01

    In connection with his announcement regarding the development of a permanently manned Space Station, President Reagan invited the United States' friends and allies to join in the Space Station program. The President's invitation was preceded by more than two years of interaction between NASA and some of its potential partners in Space Station planning activities. Attention is given to international participation in Space Station planning, international cooperation on the Space Station, the guidelines for international cooperation, and the key challenges. Questions regarding quid pro quos are considered along with aspects of technology transfer, commercial use, problems of management, and the next steps concerning the Space Station program.

  8. Sustainability of University Technology Transfer: Mediating Effect of Inventor’s Technology Service

    Directory of Open Access Journals (Sweden)

    Fang Li

    2018-06-01

    Full Text Available Based on the perspective of knowledge transfer and the technology acceptance model (TAM, this paper constructs a university technology transfer sustainable development model that considers the inventor’s technology service from the perspective of the long-term cooperation of enterprise, and analyzes the mediating effect of the inventor’s technology service on university technology transfer sustainability. By using 270 questionnaires as survey data, it is found that the availability of an inventor’s technology service has a significant positive impact on the attitude tendency and practice tendency of enterprise long-term technological cooperation; enterprise technology absorption capacity and trust between a university and an enterprise also have significant influence on an inventor’s technical service availability. Therefore, the inventor’s technology service acts as a mediator in the relationship between university technology transfer sustainability and influence factors. Universities ought to establish the technology transfer model, which focuses on the inventor’s tacit knowledge transfer service, and promotes the sustainable development of the university.

  9. Pair-bonding, romantic love, and evolution: the curious case of Homo sapiens.

    Science.gov (United States)

    Fletcher, Garth J O; Simpson, Jeffry A; Campbell, Lorne; Overall, Nickola C

    2015-01-01

    This article evaluates a thesis containing three interconnected propositions. First, romantic love is a "commitment device" for motivating pair-bonding in humans. Second, pair-bonding facilitated the idiosyncratic life history of hominins, helping to provide the massive investment required to rear children. Third, managing long-term pair bonds (along with family relationships) facilitated the evolution of social intelligence and cooperative skills. We evaluate this thesis by integrating evidence from a broad range of scientific disciplines. First, consistent with the claim that romantic love is an evolved commitment device, our review suggests that it is universal; suppresses mate-search mechanisms; has specific behavioral, hormonal, and neuropsychological signatures; and is linked to better health and survival. Second, we consider challenges to this thesis posed by the existence of arranged marriage, polygyny, divorce, and infidelity. Third, we show how the intimate relationship mind seems to be built to regulate and monitor relationships. Fourth, we review comparative evidence concerning links among mating systems, reproductive biology, and brain size. Finally, we discuss evidence regarding the evolutionary timing of shifts to pair-bonding in hominins. We conclude there is interdisciplinary support for the claim that romantic love and pair-bonding, along with alloparenting, played critical roles in the evolution of Homo sapiens. © The Author(s) 2014.

  10. The Impact of Cooperative Learning on CHC Students' Achievements and Its Changes over the Past Decade

    Science.gov (United States)

    Chen, Qiuxian; Liu, Yuan

    2017-01-01

    Informed by emergent learning theories and multiple evidenced benefits, cooperative learning has developed into a widely accepted organization mode of class in the Western context. For the same reason, cooperative learning is transferred, during the past decade, into classrooms of Confucian Heritage Culture (CHC) contexts. Concerns, however, are…

  11. Social penalty promotes cooperation in a cooperative society.

    Science.gov (United States)

    Ito, Hiromu; Yoshimura, Jin

    2015-08-04

    Why cooperation is well developed in human society is an unsolved question in biological and human sciences. Vast studies in game theory have revealed that in non-cooperative games selfish behavior generally dominates over cooperation and cooperation can be evolved only under very limited conditions. These studies ask the origin of cooperation; whether cooperation can evolve in a group of selfish individuals. In this paper, instead of asking the origin of cooperation, we consider the enhancement of cooperation in a small already cooperative society. We ask whether cooperative behavior is further promoted in a small cooperative society in which social penalty is devised. We analyze hawk-dove game and prisoner's dilemma introducing social penalty. We then expand it for non-cooperative games in general. The results indicate that cooperation is universally favored if penalty is further imposed. We discuss the current result in terms of the moral, laws, rules and regulations in a society, e.g., criminology and traffic violation.

  12. THE REGULARITY OF INFLUENCE OF TRAFFIC PARAMETERS ON THE PROBABILITY OF REALISATION OF PLANNED PASSENGER TRANSFER AT TRANSFER NODES

    Directory of Open Access Journals (Sweden)

    G. Samchuk

    2017-06-01

    Full Text Available The article deals with the definition of traffic parameters that ensure the minimum value of the transfer waiting time for passengers. On the basis of experimental studies results, a regression equation to determine the probability of realisation of the planned transfer between a pair of vehicles was proposed. Using the identified regression equation, the transfer waiting time can be assessed for any headway exceeding 7,5 min.

  13. Squids, supercurrents, and slope anomalies: Nuclear structure from heavy-ion transfer reactions

    International Nuclear Information System (INIS)

    Guidry, M.W.

    1989-01-01

    Within the past five years we have developed experimental techniques to study heavy-ion transfer reactions to high spin states in deformed nuclei. These methods have been turned into a quantitative tool to assess the influence of collective excitation on single-particle and pairing structure. I discuss some of the nuclear structure questions which are being answered in these experiments: How strong is ground state pairing? How does pairing change with angular momentum? Why is two-neutron transfer much stronger than expected at large radial separation? What is the evidence for a nuclear Josephson Effect? What is the evidence for a nuclear Berry phase effect (nuclear SQUID)? Why does one-neutron transfer populate much higher spins than would be naively expected? Conversely, why does two-neutron transfer populate much lower spins than anyone expected? The answer to each of these questions involves the influence of detailed nuclear structure on transfer reactions, and represents quantitative new information about the effect of angular momentum and excitation energy on many-body systems with a finite number of particles. 8 refs., 6 figs

  14. A non-multimacrocyclic heteroditopic receptor that cooperatively binds and effectively extracts KAcO salt.

    Science.gov (United States)

    Zakrzewski, Maciej; Kwietniewska, Natalia; Walczak, Wojciech; Piątek, Piotr

    2018-06-06

    Prepared in only three synthetic steps, a non-multimacrocyclic heteroditopic receptor binds potassium salts of halides and carboxylates with unusually high cooperativity, suggesting salt binding as associated ion-pairs. Unprecedented extraction of highly hydrophilic KAcO salt from water to organic solution is also demonstrated.

  15. Stochastic heterogeneous interaction promotes cooperation in spatial prisoner's dilemma game.

    Directory of Open Access Journals (Sweden)

    Ping Zhu

    Full Text Available Previous studies mostly investigate player's cooperative behavior as affected by game time-scale or individual diversity. In this paper, by involving both time-scale and diversity simultaneously, we explore the effect of stochastic heterogeneous interaction. In our model, the occurrence of game interaction between each pair of linked player obeys a random probability, which is further described by certain distributions. Simulations on a 4-neighbor square lattice show that the cooperation level is remarkably promoted when stochastic heterogeneous interaction is considered. The results are then explained by investigating the mean payoffs, the mean boundary payoffs and the transition probabilities between cooperators and defectors. We also show some typical snapshots and evolution time series of the system. Finally, the 8-neighbor square lattice and BA scale-free network results indicate that the stochastic heterogeneous interaction can be robust against different network topologies. Our work may sharpen the understanding of the joint effect of game time-scale and individual diversity on spatial games.

  16. Suppression of bremsstrahlung and pair production due to environmental factors

    International Nuclear Information System (INIS)

    Klein, Spencer

    1999-01-01

    The environment in which bremsstrahlung and pair creation occurs can strongly affect cross sections for these processes. Because ultrarelativistic electromagnetic interactions involve very small longitudinal momentum transfers, the reactions occur gradually, spread over long distances. During this time, even relatively weak factors can accumulate enough to disrupt the interaction. In the Landau-Pomeranchuk-Migdal effect, multiple scattering reduces the bremsstrahlung and pair production cross section. This review will discuss this and a variety of other factors that can suppress bremsstrahlung and pair production, as well as related effects involving beamstrahlung and QCD processes. After surveying different theoretical approaches, experimental measurements will be covered. Recent accurate measurements by the SLAC E-146 Collaboration will be highlighted, along with several recent theoretical works relating to the experiment. (c) 1999 The American Physical Society

  17. Time evolving multi-city dependencies and robustness tradeoffs for risk-based portfolios of conservation, transfers, and cooperative water supply infrastructure development pathways

    Science.gov (United States)

    Trindade, B. C.; Reed, P. M.; Zeff, H. B.; Characklis, G. W.

    2016-12-01

    Water scarcity in historically water-rich regions such as the southeastern United States is becoming a more prevalent concern. It has been shown that cooperative short-term planning that relies on conservation and transfers of existing supplies amongst communities can be used by water utilities to mitigate the effects of water scarcity in the near future. However, in the longer term, infrastructure expansion is likely to be necessary to address imbalances between growing water demands and the available supply capacity. This study seeks to better diagnose and avoid candidate modes for system failure. Although it is becoming more common for water utilities to evaluate the robustness of their water supply, defined as the insensitivity of their systems to errors in deeply uncertain projections or assumptions, defining robustness is particularly challenging in multi-stakeholder regional contexts for decisions that encompass short management actions and long-term infrastructure planning. Planning and management decisions are highly interdependent and strongly shape how a region's infrastructure itself evolves. This research advances the concept of system robustness by making it evolve over time rather than static, so that it is applicable to an adaptive system and therefore more suited for use for combined short and long-term planning efforts. The test case for this research is the Research Triangle area of North Carolina, where the cities of Raleigh, Durham, Cary and Chapel Hill are experiencing rapid population growth and increasing concerns over drought. This study is facilitating their engagement in cooperative and robust regional water portfolio planning. The insights from this work have general merit for regions where adjacent municipalities can benefit from improving cooperative infrastructure investments and more efficient resource management strategies.

  18. 7 CFR 1779.88 - Transfers and assumptions.

    Science.gov (United States)

    2010-01-01

    ... amount amortized over a period not greater than the remaining life of the debt being transferred, and the... lender must certify that the transferor has cooperated in good faith, used due diligence to maintain the...

  19. Topological superfluids with finite-momentum pairing and Majorana fermions.

    Science.gov (United States)

    Qu, Chunlei; Zheng, Zhen; Gong, Ming; Xu, Yong; Mao, Li; Zou, Xubo; Guo, Guangcan; Zhang, Chuanwei

    2013-01-01

    Majorana fermions (MFs), quantum particles that are their own antiparticles, are not only of fundamental importance in elementary particle physics and dark matter, but also building blocks for fault-tolerant quantum computation. Recently MFs have been intensively studied in solid state and cold atomic systems. These studies are generally based on superconducting pairing with zero total momentum. On the other hand, finite total momentum Cooper pairings, known as Fulde-Ferrell (FF) Larkin-Ovchinnikov (LO) states, were widely studied in many branches of physics. However, whether FF and LO superconductors can support MFs has not been explored. Here we show that MFs can exist in certain types of gapped FF states, yielding a new quantum matter: topological FF superfluids/superconductors. We demonstrate the existence of such topological FF superfluids and the associated MFs using spin-orbit-coupled degenerate Fermi gases and derive their parameter regions. The implementation of topological FF superconductors in semiconductor/superconductor heterostructures is also discussed.

  20. What's new in the proton transfer reaction from pyranine to water? A femtosecond study of the proton transfer dynamics

    International Nuclear Information System (INIS)

    Prayer, C.; Gustavsson, T.; Tran-Thi, T.-H.

    1996-01-01

    The proton transfer from excited pyranine to water is studied by the femtosecond fluorescence upconversion technique. It is shown for the first time that the proton transfer reaction in water proceeds by three successive steps: the solvent cage relaxation, the specific solute-solvent hydrogen-bond formation and finally the ion pair dissociation/diffusion

  1. Two-neutron transfer reactions with heavy-deformed nuclei

    International Nuclear Information System (INIS)

    Price, C.; Landowne, S.; Esbensen, H.

    1988-01-01

    In a recent communication we pointed out that one can combine the macroscopic model for two-particle transfer reactions on deformed nuclei with the sudden limit approximation for rotational excitation, and thereby obtain a practical method for calculating transfer reactions leading to high-spin states. As an example, we presented results for the reaction 162 Dy( 58 Ni, 60 Ni) 160 Dy populating the ground-state rotational band up to the spin I = 14 + state. We have also tested the validity of the sudden limit for the inelastic excitation of high spin states and we have noted how the macroscopic model may be modified to allow for more microscopic nuclear structure effects in an application to diabolic pair-transfer processes. This paper describes our subsequent work in which we investigated the systematic features of pair-transfer reactions within the macroscopic model by using heavier projectiles to generate higher spins and by decomposing the cross sections according to the multipolarity of the transfer interaction. Particular attention is paid to characteristic structures in the angular distributions for the lower spin states and how they depend on the angular momentum carried by the transferred particles. 11 refs., 3 figs

  2. Threshold Games and Cooperation on Multiplayer Graphs.

    Directory of Open Access Journals (Sweden)

    Kaare B Mikkelsen

    Full Text Available The study investigates the effect on cooperation in multiplayer games, when the population from which all individuals are drawn is structured-i.e. when a given individual is only competing with a small subset of the entire population.To optimize the focus on multiplayer effects, a class of games were chosen for which the payoff depends nonlinearly on the number of cooperators-this ensures that the game cannot be represented as a sum of pair-wise interactions, and increases the likelihood of observing behaviour different from that seen in two-player games. The chosen class of games are named "threshold games", and are defined by a threshold, M > 0, which describes the minimal number of cooperators in a given match required for all the participants to receive a benefit. The model was studied primarily through numerical simulations of large populations of individuals, each with interaction neighbourhoods described by various classes of networks.When comparing the level of cooperation in a structured population to the mean-field model, we find that most types of structure lead to a decrease in cooperation. This is both interesting and novel, simply due to the generality and breadth of relevance of the model-it is likely that any model with similar payoff structure exhibits related behaviour. More importantly, we find that the details of the behaviour depends to a large extent on the size of the immediate neighbourhoods of the individuals, as dictated by the network structure. In effect, the players behave as if they are part of a much smaller, fully mixed, population, which we suggest an expression for.

  3. The case for spin-fluctuation induced pairing in Ba{sub 1-x}K{sub x}Fe{sub 2}As{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Thomas U.

    2017-03-07

    The microscopic mechanism and the experimental identification of unconventional superconductivity is one of the most vexing problems of contemporary condensed matter physics. Raman spectroscopy provides a new avenue for this quest by accessing the hierarchy of superconducting pairing propensities. The doping-dependent study of competing pairing channels in Ba{sub 1-x}K{sub x}Fe{sub 2}As{sub 2} for 0.22 ≤ x ≤ 0.70 is one of the main aspects of this thesis. The observations demonstrate the importance of spin fluctuations for Cooper pairing.

  4. Ion pairing in ionic liquids

    International Nuclear Information System (INIS)

    Kirchner, Barbara; Malberg, Friedrich; Firaha, Dzmitry S; Hollóczki, Oldamur

    2015-01-01

    In the present article we briefly review the extensive discussion in literature about the presence or absence of ion pair-like aggregates in ionic liquids. While some experimental studies point towards the presence of neutral subunits in ionic liquids, many other experiments cannot confirm or even contradict their existence. Ion pairs can be detected directly in the gas phase, but no direct method is available to observe such association behavior in the liquid, and the corresponding indirect experimental proofs are based on such assumptions as unity charges at the ions. However, we have shown by calculating ionic liquid clusters of different sizes that assuming unity charges for ILs is erroneous, because a substantial charge transfer is taking place between the ionic liquid ions that reduce their total charge. Considering these effects might establish a bridge between the contradicting experimental results on this matter. Beside these results, according to molecular dynamics simulations the lifetimes of ion–ion contacts and their joint motions are far too short to verify the existence of neutral units in these materials. (topical review)

  5. Electronic pairing mechanism due to band modification with increasing pair number

    International Nuclear Information System (INIS)

    Mizia, J.

    1995-01-01

    It is shown that a shift of an electron band with electron occupation number n, which is changing during the transition to the superconducting state, can lower the total energy of the system. In fact it will bring a negative contribution to the pairing potential, which is proportional to the product of the electron band shift with occupation number and the charge transfer during the transition to the superconducting state. The shift of the electron band comes from the change of stresses and the change of correlation effects in the CuO 2 plane with n, that in turn is caused by the changing oxygen concentration. This model explains the phenomenological success of Hirsch's model, which gives no explanation how the band shift in energy can give rise to superconductivity. (orig.)

  6. Pedagogic Effects of Cooperative Learning Assessment in the Chemistry I Classroom

    Science.gov (United States)

    Champion, Jennifer

    Over the last 30 years, there has been ongoing research and debate concerning the implementation and effectiveness of cooperative learning in the classroom. The problem is determining the fair assignment of individual grades while using cooperative work. Teachers have limited time to compile, equate, and convert group grades for each student. The purpose of this quasi-experimental study was to examine the impact of cooperative learning assessment on student achievement. This study aimed to determine the relationship between teacher-assigned/group-elected laboratory positions (independent variable) and academic achievement (dependent variable) while using the cards on the table approach of cooperative learning assessment. Participants consisted of 2 classes of Chemistry I students enrolled in a small rural school system. Alternative assessment practices such as the cards on the table approach of cooperative learning assessment were examined and discussed. Results of ANCOVA analyses indicated no significance difference in the adjusted scores between teacher-assigned versus group-elected laboratory positions within structured laboratory groups on the academic achievement of Chemistry I students as measured by a standardized pretest/posttest while using the cooperative learning assessment. Conducting paired samples t tests revealed the group-assigned students improved significantly from pretest to posttest while the teacher-assigned students had no significant improvements. The study may affect positive social change by helping teachers develop guidelines for fair assessment of individual grades from cooperative learning activities and to enrich the academic repertoire of students, increasing their awareness of accountability and collaboration.

  7. Cooperation between territorial communities: theory and practice

    Directory of Open Access Journals (Sweden)

    П. М. Любченко

    2015-05-01

    Full Text Available Problem Setting. The paper analyzes the problems in the system of legal regulation of cooperation between communities, highlights the advantages and disadvantages of such cooperation in Ukrainian local government. Analysis of the recent researches and publications. The legal basis for cooperation in the field of local government are provisions of the Constitution and laws of Ukraine, by-laws. The organizational principles of communities cooperation, principles, forms and mechanisms of such cooperation and its promotion, financing and monitoring prescribed by the Law of Ukraine «On cooperation of local communities» 17 June 2014, which provides five possible forms of cooperation. Paper main body. The first form - delegation to one party of cooperation by another parties of cooperation execution of one or few tasks with transferring of appropriate resources - one of the most difficult to implement, therefore in Ukraine it is not yet implemented. The second form – realization of joint projects, involving coordination of activities between parties of cooperation and accumulating them for a certain period resources to joint implementation of appropriate measures - one of the most common. This  form is popular because of its simplicity and versatility. Parties are determining the purpose of the project, terms and conditions of its implementation, a list of activities and conditions for their implementation, financial liabilities, other forms of local governments participation in implementation of the project and mechanism of coordination. The third and fourth forms aimed on the creation and maintenance of communal enterprises, institutions and organizations - joint infrastructure projects by parties of cooperation. This form of cooperation with the prospect of widespread use because it is aimed at ensuring effective use of resources of local communities based on common application available in one of the subjects of cooperation of municipal

  8. Transfer of radiation technology to developing countries

    Science.gov (United States)

    Markovic, Vitomir; Ridwan, Mohammad

    1993-10-01

    Transfer of technology is a complex process with many facets, options and constraints. While the concept is an important step in bringing industrialization process to agricultural based countries, it is clear, however, that a country will only benefit from a new technology if it addresses a real need, and if it can be absorbed and adapted to suit the existing cultural and technological base. International Atomic Energy Agency, as UN body, has a mandate to promote nuclear applicationsand assist Member States in transfer of technology for peaceful applications. This mandate has been pursued by many different mechanisms developed in the past years: technical assistance, coordinated research programmes, scientific and technical meetings, publications, etc. In all these activities the Agency is the organizer and initiator, but main contributions come from expert services from developed countries and, increasingly, from developing countries themselves. The technical cooperation among developing coutries more and more becomes part of different programmes. In particular, regional cooperation has been demonstrated as an effective instrument for transfer of technology from developed and among developing countries. Some examples of actual programmes are given.

  9. Heat transfer between immiscible liquids enhanced by gas bubbling

    International Nuclear Information System (INIS)

    Greene, G.A.; Schwarz, C.E.; Klages, J.; Klein, J.

    1982-08-01

    The phenomena of core-concrete interactions impact upon containment integrity of light water reactors (LWR) following postulated complete meltdown of the core by containment pressurization, production of combustible gases, and basemat penetration. Experiments have been performed with non-reactor materials to investigate one aspect of this problem, heat transfer between overlying immiscible liquids whose interface is disturbed by a transverse non-condensable gas flux emanating from below. Hydrodynamic studies have been performed to test a criterion for onset of entrainment due to bubbling through the interface and subsequent heat transfer studies were performed to assess the effect of bubbling on interfacial heat transfer rates, both with and without bubble induced entrainment. Non-entraining interfacial heat transfer data with mercury-water/oil fluid pairs were observed to be bounded from below within a factor of two to three by the Szekeley surface renewal heat transfer model. However heat transfer data for fluid pairs which are found to entrain (water-oil), believed to be characteristic of molten reactor core-concrete conditions, were measured to be up to two orders of magnitude greater than surface renewal predictions and are calculated by a simple entrainment heat transfer model

  10. Pairing from dynamically screened Coulomb repulsion in bismuth

    Science.gov (United States)

    Ruhman, Jonathan; Lee, Patrick A.

    2017-12-01

    Recently, Prakash et al. have discovered bulk superconductivity in single crystals of bismuth, which is a semimetal with extremely low carrier density. At such low density, we argue that conventional electron-phonon coupling is too weak to be responsible for the binding of electrons into Cooper pairs. We study a dynamically screened Coulomb interaction with effective attraction generated on the scale of the collective plasma modes. We model the electronic states in bismuth to include three Dirac pockets with high velocity and one hole pocket with a significantly smaller velocity. We find a weak-coupling instability, which is greatly enhanced by the presence of the hole pocket. Therefore we argue that bismuth is the first material to exhibit superconductivity driven by retardation effects of Coulomb repulsion alone. By using realistic parameters for bismuth we find that the acoustic plasma mode does not play the central role in pairing. We also discuss a matrix element effect, resulting from the Dirac nature of the conduction band, which may affect Tc in the s -wave channel without breaking time-reversal symmetry.

  11. Exact mapping of the dx2-y2 Cooper-pair wavefunction onto the spin fluctuations in cuprates: the Fermi surface as a driver for 'high Tc' superconductivity

    International Nuclear Information System (INIS)

    McDonald, Ross D; Harrison, Neil; Singleton, John

    2009-01-01

    We propose that the extraordinarily high superconducting transition temperatures in the cuprates are driven by an exact mapping of the d x 2 -y 2 Cooper-pair wavefunction onto the incommensurate spin fluctuations observed in neutron-scattering experiments. This is manifested in the direct correspondence between the inverse of the incommensurability factor δ seen in inelastic neutron-scattering experiments and the measured superconducting coherence length ξ 0 . Strikingly, the relationship between ξ 0 and δ is valid for both La 2-x Sr x CuO 4 and YBa 2 Cu 3 O 7-x , suggesting a common mechanism for superconductivity across the entire hole-doped cuprate family. Using data from recent quantum-oscillation experiments in the cuprates, we propose that the fluctuations responsible for superconductivity are driven by a Fermi-surface instability. On the basis of these findings, one can specify the optimal characteristics of a solid that will exhibit 'high T c ' superconductivity. (fast track communication)

  12. Design of special purpose database for credit cooperation bank business processing network system

    Science.gov (United States)

    Yu, Yongling; Zong, Sisheng; Shi, Jinfa

    2011-12-01

    With the popularization of e-finance in the city, the construction of e-finance is transfering to the vast rural market, and quickly to develop in depth. Developing the business processing network system suitable for the rural credit cooperative Banks can make business processing conveniently, and have a good application prospect. In this paper, We analyse the necessity of adopting special purpose distributed database in Credit Cooperation Band System, give corresponding distributed database system structure , design the specical purpose database and interface technology . The application in Tongbai Rural Credit Cooperatives has shown that system has better performance and higher efficiency.

  13. Teaching Adolescents EFL by Integrating Think-Pair-Share and Reading Strategy Instruction: A Quasi-Experimental Study

    Science.gov (United States)

    Shih, Ying-Chun; Reynolds, Barry Lee

    2015-01-01

    Think-Pair-Share, a cooperative discussion strategy developed by Frank Lyman and colleagues (1981), is often utilized in first language contexts but rarely in second language (L2) contexts. To investigate its usefulness in the L2 context, a traditional English as a Foreign Language (EFL) reading class was transformed by integrating…

  14. Goldstone mode and pair-breaking excitations in atomic Fermi superfluids

    Science.gov (United States)

    Hoinka, Sascha; Dyke, Paul; Lingham, Marcus G.; Kinnunen, Jami J.; Bruun, Georg M.; Vale, Chris J.

    2017-10-01

    Spontaneous symmetry breaking is a central paradigm of elementary particle physics, magnetism, superfluidity and superconductivity. According to Goldstone's theorem, phase transitions that break continuous symmetries lead to the existence of gapless excitations in the long-wavelength limit. These Goldstone modes can become the dominant low-energy excitation, showing that symmetry breaking has a profound impact on the physical properties of matter. Here, we present a comprehensive study of the elementary excitations in a homogeneous strongly interacting Fermi gas through the crossover from a Bardeen-Cooper-Schrieffer (BCS) superfluid to a Bose-Einstein condensate (BEC) of molecules using two-photon Bragg spectroscopy. The spectra exhibit a discrete Goldstone mode, associated with the broken-symmetry superfluid phase, as well as pair-breaking single-particle excitations. Our techniques yield a direct determination of the superfluid pairing gap and speed of sound in close agreement with strong-coupling theories.

  15. Pairing in exotic neutron-rich nuclei near the drip line and in the crust of neutron stars

    Science.gov (United States)

    Pastore, A.; Margueron, J.; Schuck, P.; Viñas, X.

    2013-09-01

    Exotic and drip-line nuclei as well as nuclei immersed in a low-density gas of neutrons in the inner crust of neutron stars are systematically investigated with respect to their neutron pairing properties. This is done using Skyrme density-functional and different pairing forces such as a density-dependent contact interaction and a separable form of a finite-range Gogny interaction. Hartree-Fock-Bogoliubov (HFB) and Bardeen-Cooper-Schrieffer (BCS) theories are compared. It is found that neutron pairing is reduced towards the drip line while overcast by strong shell effects. Furthermore, resonances in the continuum can have an important effect counterbalancing the tendency of reduction and leading to a persistence of pairing at the drip line. It is also shown that in these systems the difference between HFB and BCS approaches can be quantitatively large.

  16. Using reservoir-engineering to convert a coherent signal in optomechanics with small optomechanical cooperativity

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Tao, E-mail: suiyueqiaoqiao@163.com [Key Lab of Coherent Light, Atomic and Molecular Spectroscopy, Ministry of Education, and College of Physics, Jilin University, Changchun 130012 (China); College of Physics, Tonghua Normal University, Tonghua 134000 (China); Wang, Tie [Department of Physics, College of Science, Yanbian University, Yanji, Jilin 133002 (China); Fu, Changbao [College of Physics, Tonghua Normal University, Tonghua 134000 (China); Su, Xuemei, E-mail: suxm@jlu.edu.cn [Key Lab of Coherent Light, Atomic and Molecular Spectroscopy, Ministry of Education, and College of Physics, Jilin University, Changchun 130012 (China)

    2017-05-10

    Optomechanical dark mode plays a central role in effective mechanically-mediated conversion of two different cavity fields. In this paper, we present a more efficient method to utilize the dark mode to transfer a coherent signal. When an auxiliary cavity mode is exploited, two approaches are proposed to effectively eliminate the optomechanical bright mode, and only the optomechanical dark mode is left to facilitate state transfer. Even with small cooperativity and different losses for the two target modes, the internal cavity mode-conversion efficiency can also reach unity. - Highlights: • Reservoir-engineering is used for state conversion. • The optomechanical bright mode can be absolutely eliminated. • Small cooperativity and different losses are feasible for ideal conversion efficiency.

  17. Multiple effect of social influence on cooperation in interdependent network games

    Science.gov (United States)

    Jiang, Luo-Luo; Li, Wen-Jing; Wang, Zhen

    2015-10-01

    The social influence exists widely in the human society, where individual decision-making process (from congressional election to electronic commerce) may be affected by the attitude and behavior of others belonging to different social networks. Here, we couple the snowdrift (SD) game and the prisoner’s dilemma (PD) game on two interdependent networks, where strategies in both games are associated by social influence to mimick the majority rule. More accurately, individuals’ strategies updating refers to social learning (based on payoff difference) and above-mentioned social influence (related with environment of interdependent group), which is controlled by social influence strength s. Setting s = 0 decouples the networks and returns the traditional network game; while its increase involves the interactions between networks. By means of numerous Monte Carlo simulations, we find that such a mechanism brings multiple influence to the evolution of cooperation. Small s leads to unequal cooperation level in both games, because social learning is still the main updating rule for most players. Though intermediate and large s guarantees the synchronized evolution of strategy pairs, cooperation finally dies out and reaches a completely dominance in both cases. Interestingly, these observations are attributed to the expansion of cooperation clusters. Our work may provide a new understanding to the emergence of cooperation in intercorrelated social systems.

  18. Technology transfer trends in Indian space programme

    Science.gov (United States)

    Sridhara Murthi, K. R.; Shoba, T. S.

    2010-10-01

    Indian space programme, whose objectives involve acceleration of economic and social development through applications of space technology, has been engaged in the development of state-of-the-art satellite systems, launch vehicles and equipment necessary for applications. Even during the early phase of evolution of this Programme, deliberate policies have been adopted by the national space agency, namely, Indian Space Research Organisation (ISRO), to promote spin-off benefit from the technologies developed for the use of space projects. Consistently adhering to this policy, ISRO has transferred over 280 technologies till date, spanning a wide spectrum of disciplines. This has resulted in a fruitful two-way cooperation between a number of SMEs and the ISRO. In order to make the technology transfer process effective, ISRO has adopted a variety of functional and organizational policies that included awareness building measures, licensee selection methods, innovative contract systems, diverse transfer processes, post licencing services and feedback mechanisms. Besides analyzing these policies and their evolution, the paper discusses various models adopted for technology transfer and their impact on assessment. It also touches upon relevant issues relating to creating interface between public funded R&D and the private commercial enterprises. It suggests few models in which international cooperation could be pursued in this field.

  19. Computational studies of a cut-wire pair and combined metamaterials

    International Nuclear Information System (INIS)

    Nguyen, Thanh Tung; Lievens, Peter; Lee, Young Pak; Vu, Dinh Lam

    2011-01-01

    The transfer-matrix method and finite-integration simulations show how the transmission properties of combined metamaterials, which consist of metallic cut-wire pairs and continuous wires, are affected by geometric parameters. The corresponding effective permittivity and permeability are retrieved from the complex scattering parameters using the standard retrieval procedure. The electromagnetic properties of the cut-wire pair as well as the left-handed behavior of the combined structure are understood by the effective medium theory. In addition, the dimensional dependence of transmission properties, the shapes of cut-wire pairs and continuous wire, and the impact of dielectric spacer are both examined. Finally, by expanding the results of previous research (Koschny et al 2003 Phys. Rev. Lett. 93 016608), we generalize the transmission picture of combined structures in terms of the correlation between electric and magnetic responses. (review)

  20. Cooperative phenomena within organised bi-dimensional structures

    International Nuclear Information System (INIS)

    Armand, Franck

    2001-01-01

    In this report produced for an Accreditation to Supervise Research, the author defines a cooperative phenomenon as a phenomenon occurring each time a cooperation between elementary entities results in a collective property which exceeds the simple addition of disorganised individual properties. He reports works and researches which show that such phenomena can be generated by molecular architectures developed in laboratory, but also requires an appropriate organisation of active elementary entities. This can be obtained by self-organisation in solution. However, many applications assume the use of solid phases, and notably thin layers. In this respect, the Langmuir-Blodgett technique and self-assembly are very interesting techniques to produce mono-molecular thin layers, without however controlling molecule in-plane orientation and organisation. The author propose an overview of his works which aimed at obtaining this control, and reports three examples of cooperative phenomena: the generation of a second harmonic, spin transition with hysteresis, and electron conduction (one-dimensional and bi-dimensional electron transfer). The report also contains articles published in various scientific publications, and contributions to congresses [fr

  1. Investigation of sensitizer ions tunable-distribution in fluoride nanoparticles for efficient accretive three-center energy transfer

    International Nuclear Information System (INIS)

    Guo, Hui; Yu, Hua; Lao, Aiqing; Chang, Lifen; Gao, Shaohua; Zhang, Haoxiong; Zhou, Taojie; Zhao, Lijuan

    2014-01-01

    Cooperative upconversion luminescence of Yb 3+ -Yb 3+ couples and three-center energy transfer mechanisms have been deeply investigated in Yb 3+ doped and Yb 3+ -Tb 3+ co-doped β-PbF 2 nanoparticles. As sensitizer ions, the distribution of Yb 3+ ions, which is a key factor that affects the cooperative upconversion luminescence and three-center energy transfer processes, can be tuned by the structure of nanoparticles. Based on the three-center distributions in tetragonal PbYb x Tb 1−x F 5 nanoparticles, two different energy transfer models, Cooperative Energy Transfer (CET) and Accretive Energy Transfer (AET) mechanisms were established. Especially, AET model is observed and verified in this work for the first time. Experimental results obtained from photoluminescence spectroscopy study are in agreement with the theoretical calculations by applying rate equations in these models, strongly supporting the proposed three-center energy transfer mechanisms. The sensitization between Yb 3+ ions only existing in AET process can greatly improve the energy transfer rates, further to enhance the quantum efficiency. The results that the calculated luminescence quantum efficiency in AET quantum cutting process is much higher than that in CET process (134% and 104%, respectively), can benefit for further increasing the conversion efficiency of c-Si solar cells.

  2. It's not just lunch: extra-pair commensality can trigger sexual jealousy.

    Directory of Open Access Journals (Sweden)

    Kevin M Kniffin

    Full Text Available Do people believe that sharing food might involve sharing more than just food? To investigate this, participants were asked to rate how jealous they (Study 1--or their best friend (Study 2--would be if their current romantic partner were contacted by an ex-romantic partner and subsequently engaged in an array of food- and drink-based activities. We consistently find--across both men and women--that meals elicit more jealousy than face-to-face interactions that do not involve eating, such as having coffee. These findings suggest that people generally presume that sharing a meal enhances cooperation. In the context of romantic pairs, we find that participants are attuned to relationship risks that extra-pair commensality can present. For romantic partners left out of a meal, we find a common view that lunch, for example, is not "just lunch."

  3. It's not just lunch: extra-pair commensality can trigger sexual jealousy.

    Science.gov (United States)

    Kniffin, Kevin M; Wansink, Brian

    2012-01-01

    Do people believe that sharing food might involve sharing more than just food? To investigate this, participants were asked to rate how jealous they (Study 1)--or their best friend (Study 2)--would be if their current romantic partner were contacted by an ex-romantic partner and subsequently engaged in an array of food- and drink-based activities. We consistently find--across both men and women--that meals elicit more jealousy than face-to-face interactions that do not involve eating, such as having coffee. These findings suggest that people generally presume that sharing a meal enhances cooperation. In the context of romantic pairs, we find that participants are attuned to relationship risks that extra-pair commensality can present. For romantic partners left out of a meal, we find a common view that lunch, for example, is not "just lunch."

  4. Channel Measurements and Characteristics for Cooperative Positioning Applications

    DEFF Research Database (Denmark)

    Wang, Wei; Steinböck, Gerhard; Jost, Thomas

    2012-01-01

    We have conducted an indoor channel measurement campaign to characterize the propagation channel for the development of cooperative positioning algorithms. The campaign focused particularly on the characteristics of multi-link channels with applications to positioning. In this contribution we...... present the measurement campaign and preliminary results on correlation characteristics of the received power. It is observed that the link-pair log power is uncorrelated. Moreover, the received log power can be modeled by realizations of independent Gaussian distributions for each link, based...... on the measured results....

  5. KEEFEKTIFAN THINK-PAIR-SHARE UNTUK MENINGKATKAN PEMAHAMAN MAHASISWA MENGENAI KONSEP DASAR HUBUNGAN MASYARAKAT

    Directory of Open Access Journals (Sweden)

    Nina Oktarina

    2016-01-01

    Full Text Available Intention of research this is to improve quality of study of public relations, to increase the spirit of learning student, to uplift skill teacher in developing model and study media and to increase the achievement learn student. This research is research of class action which is consisted of three cycle. Result of research show achievement learn natural student of improvement in each its cycle. learn student of before applying of method Think-Pair-Share 0%, after applying of method Think-Pair-Share, learn from student after conducted by a final test is 76,67%. Enthusiasm, livelines and student cooperation in course of study of 1-4 result is good ( 3,39. Perception result hit skill teacher in study management by using method Think-Pair-Share with 1-4 showing good result with rate from cycle 1, cycle 2, and cycle 3 is 3,38. The score represent rate from entire/all aspect perceived at three

  6. Latin-American Co-operation in Biotechnology Programme: Industrial penicillin amidase for 6 amino penicillanic acid production

    Directory of Open Access Journals (Sweden)

    Dolly Montoya C.

    2001-07-01

    Full Text Available This work evaluates technological and economic transference related to the Production of Penicillin Amidase for use in 6 Amine Penicillanic acid (6-APA Production Project, wich is a part of the United Nations1 Regional Biotechnology Programme for Latin America and the Caribbean. This paper analyses the evolution of international cooperation by looking at the project's development. The methodology used includes analysis of: the project's development; participant and budgetary goals; results; copyright; project conditions; and sale of biocatalyst and 6-APA. All technical objectives were achieved; international co-operation, as well as co-operation between Industry and University were successful. Technological transference to the pilot plant was effective; many students involved in the project were simultaneously taking M.Sc. and Ph.D's courses. Nevertheless, neither the technology necessary for the biocatalyst's manufacture nor the biocatalyst itself were used. Analysis of the project has provided some orientation concerning those internal and external problems which arose during the development and sale of biotechnology in our countries and has tried to propose some alternatives for taking advantage of international co-operation.

  7. A User Cooperation Stimulating Strategy Based on Cooperative Game Theory in Cooperative Relay Networks

    Directory of Open Access Journals (Sweden)

    Ping Zhang

    2009-01-01

    Full Text Available This paper proposes a user cooperation stimulating strategy among rational users. The strategy is based on cooperative game theory and enacted in the context of cooperative relay networks. Using the pricing-based mechanism, the system is modeled initially with two nodes and a Base Station (BS. Within this framework, each node is treated as a rational decision maker. To this end, each node can decide whether to cooperate and how to cooperate. Cooperative game theory assists in providing an optimal system utility and provides fairness among users. Under different cooperative forwarding modes, certain questions are carefully investigated, including “what is each node's best reaction to maximize its utility?” and “what is the optimal reimbursement to encourage cooperation?” Simulation results show that the nodes benefit from the proposed cooperation stimulating strategy in terms of utility and thus justify the fairness between each user.

  8. A User Cooperation Stimulating Strategy Based on Cooperative Game Theory in Cooperative Relay Networks

    Directory of Open Access Journals (Sweden)

    Jiang Fan

    2009-01-01

    Full Text Available This paper proposes a user cooperation stimulating strategy among rational users. The strategy is based on cooperative game theory and enacted in the context of cooperative relay networks. Using the pricing-based mechanism, the system is modeled initially with two nodes and a Base Station (BS. Within this framework, each node is treated as a rational decision maker. To this end, each node can decide whether to cooperate and how to cooperate. Cooperative game theory assists in providing an optimal system utility and provides fairness among users. Under different cooperative forwarding modes, certain questions are carefully investigated, including "what is each node's best reaction to maximize its utility?" and "what is the optimal reimbursement to encourage cooperation?" Simulation results show that the nodes benefit from the proposed cooperation stimulating strategy in terms of utility and thus justify the fairness between each user.

  9. Essentially Optimal Universally Composable Oblivious Transfer

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Nielsen, Jesper Buus; Orlandi, Claudio

    2009-01-01

    . Communication complexity: it communicates O(1) group elements to transfer one out of two group elements. The Big-O notation hides 32, meaning that the communication is probably not optimal, but is essentially optimal in that the overhead is at least constant. Our construction is based on pairings, and we assume......Oblivious transfer is one of the most important cryptographic primitives, both for theoretical and practical reasons and several protocols were proposed during the years. We provide the first oblivious transfer protocol which is simultaneously optimal on the following list of parameters: Security...

  10. U.S.-Mexican Security Cooperation: the Merida Initiative and Beyond

    Science.gov (United States)

    2010-08-16

    2010, those funds had yet to be transferred from the State Department to USAID for implementation. 71 “Cárteles Perturban al Sistema Carcelario,” El...Quejas a Web .” Milenio. July 28, 2010. U.S.-Mexican Security Cooperation: the Mérida Initiative and Beyond Congressional Research Service 27

  11. Negative association between parental care and sibling cooperation in earwigs: a new perspective on the early evolution of family life?

    Science.gov (United States)

    Kramer, J; Thesing, J; Meunier, J

    2015-07-01

    The evolution of family life requires net fitness benefits for offspring, which are commonly assumed to mainly derive from parental care. However, an additional source of benefits for offspring is often overlooked: cooperative interactions among juvenile siblings. In this study, we examined how sibling cooperation and parental care could jointly contribute to the early evolution of family life. Specifically, we tested whether the level of food transferred among siblings (sibling cooperation) in the European earwig Forficula auricularia (1) depends on the level of maternal food provisioning (parental care) and (2) is translated into offspring survival, as well as female investment into future reproduction. We show that higher levels of sibling food transfer were associated with lower levels of maternal food provisioning, possibly reflecting a compensatory relationship between sibling cooperation and maternal care. Furthermore, the level of sibling food transfer did not influence offspring survival, but was associated with negative effects on the production of the second and terminal clutch by the tending mothers. These findings indicate that sibling cooperation could mitigate the detrimental effects on offspring survival that result from being tended by low-quality mothers. More generally, they are in line with the hypothesis that sibling cooperation is an ancestral behaviour that can be retained to compensate for insufficient levels of parental investment. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

  12. 14 CFR 1260.73 - Transfers, novations, and change of name agreements.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Transfers, novations, and change of name agreements. 1260.73 Section 1260.73 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GRANTS AND COOPERATIVE AGREEMENTS General Post-Award Requirements § 1260.73 Transfers, novations, and...

  13. Early miscarriage rate in lean polycystic ovary syndrome women after euploid embryo transfer - a matched-pair study.

    Science.gov (United States)

    Luo, Lu; Gu, Fang; Jie, Huying; Ding, Chenhui; Zhao, Qiang; Wang, Qiong; Zhou, Canquan

    2017-11-01

    The early miscarriage rate is reported to be higher in patients with polycystic ovary syndrome (PCOS) compared with non-PCOS patients. However, whether PCOS is an independent risk factor for early miscarriage is still controversial; to what extent embryonic aneuploidy accounts for miscarriages of PCOS is still unknown. In this 1:3 matched-pair study, 67 lean PCOS patients and 201 controls matched for age, body mass index (BMI) and embryo scores undergoing a single euploid blastocyst transfer in vitrified-warmed cycles were analysed. Clinical pregnancy, early miscarriage and live birth rates were compared. Logistic regression analysis was performed to further evaluate the factors associated with early miscarriage and live birth. Clinical pregnancy rates were 50.7% in PCOS and 55.2% in control groups. Early miscarriage rate was significantly (P = 0.029) increased in the PCOS group compared with controls; non-PCOS patients had a significantly higher live birth rate than PCOS patients, P PCOS was significantly associated with a higher risk of early miscarriage and decreased chance of live birth. In conclusion, PCOS in women undergoing pre-implantation genetic diagnosis may, independently from BMI and karyotype, increase the risk of miscarriage. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  14. The economic and social significance of RCA regional co-operative projects

    International Nuclear Information System (INIS)

    Fowler, E.E.

    1979-01-01

    The regional Co-operative Agreement for Research, Development and Training Related to Nuclear Science and Technology (RCA) is an established and valuable instrument between the International Atomic Energy Agency (IAEA) and Member States in South Asia, Southeast Asia and the Pacific or Far East for assisting in the transfer of modern technology to areas having economic and social importance to the region. The purpose of this review is to identify on-going or planned work which is designed to help achieve this goal. Currently approved RCA Regional Co-operative Research Projects are listed

  15. Magnetization induced by odd-frequency spin-triplet Cooper pairs in a Josephson junction with metallic trilayers

    Science.gov (United States)

    Hikino, S.; Yunoki, S.

    2015-07-01

    We theoretically study the magnetization inside a normal metal induced in an s -wave superconductor/ferromagnetic metal/normal metal/ferromagnetic metal/s -wave superconductor (S /F 1 /N /F 2 /S ) Josephson junction. Using the quasiclassical Green's function method, we show that the magnetization becomes finite inside the N . The origin of this magnetization is due to odd-frequency spin-triplet Cooper pairs formed by electrons of equal and opposite spins, which are induced by the proximity effect in the S /F 1 /N /F 2 /S junction. We find that the magnetization M (d ,θ ) in the N can be decomposed into two parts, M (d ,θ ) =MI(d ) +MII(d ,θ ) , where θ is the superconducting phase difference between the two S s and d is the thickness of N . The θ -independent magnetization MI(d ) exists generally in S /F junctions, while MII(d ,θ ) carries all θ dependence and represents the fingerprint of the phase coherence between the two S s in Josephson junctions. The θ dependence thus allows us to control the magnetization in the N by tuning θ for a fixed d . We show that the θ -independent magnetization MI(d ) weakly decreases with increasing d , while the θ -dependent magnetization MII(d ,θ ) rapidly decays with d . Moreover, we find that the time-averaged magnetization exhibits a discontinuous peak at each resonance dc voltage Vn=n ℏ ωS/2 e (n : integer) when dc voltage V as well as ac voltage vac(t ) with frequency ωS are both applied to the S /F 1 /N /F 2 /S junction. This is because MII(d ,θ ) oscillates generally in time t (ac magnetization) with d θ /d t =2 e [V +vac(t ) ]/ℏ and thus =0 , but can be converted into the time-independent dc magnetization for the dc voltage at Vn. We also discuss that the magnetization induced in the N can be measurably large in realistic systems. Therefore, the measurement of the induced magnetization serves as an alternative way to detect the phase coherence between the two S s in Josephson junctions. Our results

  16. Transient Exciplex Formation Electron Transfer Mechanism

    OpenAIRE

    Michael G. Kuzmin; Irina V. Soboleva; Elena V. Dolotova

    2011-01-01

    Transient exciplex formation mechanism of excited-state electron transfer reactions is analyzed in terms of experimental data on thermodynamics and kinetics of exciplex formation and decay. Experimental profiles of free energy, enthalpy, and entropy for transient exciplex formation and decay are considered for several electron transfer reactions in various solvents. Strong electronic coupling in contact pairs of reactants causes substantial decrease of activation energy relative to that for c...

  17. PENGARUH PENGGUNAAN ALAT PERAGA BERBASIS KONSEP GEOMETRI PADA MODEL PEMBELAJARAN KOOPERATIF TIPE THINK PAIR SHARE

    Directory of Open Access Journals (Sweden)

    Sulaiman Sulaiman

    2015-10-01

    Full Text Available Abstract The research is experimental research. This study aims to determine the difference in average mathematics students learning outcomes between learning with and without the use of props Pythagoras on cooperative learning model Think Pair Share (TPS. The population was all the students in second grade of SMP Negeri 1 Sukoharjo in the academic year 2014-2015. The samples of the research were taken by using the cluster random sampling technique.Data analysis is using chi-square test andstatistical t-test. Based onthe results ofhypothesis test obtained that there is difference in the averageresult of learningmathematicsbetween experimental classandcontrol class and the averageresults oflearning mathematicsin experimental class is higherthan in control class. Thus,the averageresult of learningthatlearningto usepropsPythagorasoncooperative learning modelThink Pair Share (TPSis higherthanlearningwithout the use ofpropsPythagoras. Keywords:Props, Phytagoras, Think Pair Share

  18. New Cooperation Modes: An Opportunity for Polish Biotechnological Clusters

    Directory of Open Access Journals (Sweden)

    Lukasz Puslecki

    2015-06-01

    Full Text Available This article reviews new cooperation forms between companies, referring to the latest data from the asap (the Association of Strategic Alliance Professionals. Potential cooperation between companies, universities and research institutes in the field of biotechnology in Poland based on a model of open innovation alliances are presented. Biopharmaceutical companies are looking for new and innovative paths of development. They try to implement new strategies to transfer their research processes to a higher level. To achieve this, biopharmaceutical companies often use open innovation model as an additional tool for developing new products. Thanks to the cooperation with universities in the framework of open innovation alliances, they can significantly reduce the risk, the cost of research, and most of all, through joint work with academic researchers on identifying disease mechanisms and on development of new drugs, they are able to create improved and appropriate medical therapy for patients.

  19. Single-phase convective heat transfer in rod bundles

    International Nuclear Information System (INIS)

    Holloway, Mary V.; Beasley, Donald E.; Conner, Michael E.

    2008-01-01

    The convective heat transfer for turbulent flow through rod bundles representative of nuclear fuel rods used in pressurized water reactors is examined. The rod bundles consist of a square array of parallel rods that are held on a constant pitch by support grids spaced axially along the rod bundle. Split-vane pair support grids, which create swirling flow in the rod bundle, as well as disc and standard support grids are investigated. Single-phase convective heat transfer coefficients are measured for flow downstream of support grids in a rod bundle. The rods are heated using direct resistance heating, and a bulk axial flow of air is used to cool the rods in the rod bundle. Air is used as the working fluid instead of water to reduce the power required to heat the rod bundle. Results indicate heat transfer enhancement for up to 10 hydraulic diameters downstream of the support grids. A general correlation is developed to predict the heat transfer development downstream of support grids. In addition, circumferential variations in heat transfer coefficients result in hot streaks that develop on the rods downstream of split-vane pair support grids

  20. Single-phase convective heat transfer in rod bundles

    Energy Technology Data Exchange (ETDEWEB)

    Holloway, Mary V. [Mechanical Engineering Department, United States Naval Academy, 590 Holloway Rd., Annapolis, MD 21402 (United States)], E-mail: holloway@usna.edu; Beasley, Donald E. [Mechanical Engineering Department, Clemson University, Clemson, SC 29634 (United States); Conner, Michael E. [Westinghouse Nuclear Fuel, 5801 Bluff Road, Columbia, SC 29250 (United States)

    2008-04-15

    The convective heat transfer for turbulent flow through rod bundles representative of nuclear fuel rods used in pressurized water reactors is examined. The rod bundles consist of a square array of parallel rods that are held on a constant pitch by support grids spaced axially along the rod bundle. Split-vane pair support grids, which create swirling flow in the rod bundle, as well as disc and standard support grids are investigated. Single-phase convective heat transfer coefficients are measured for flow downstream of support grids in a rod bundle. The rods are heated using direct resistance heating, and a bulk axial flow of air is used to cool the rods in the rod bundle. Air is used as the working fluid instead of water to reduce the power required to heat the rod bundle. Results indicate heat transfer enhancement for up to 10 hydraulic diameters downstream of the support grids. A general correlation is developed to predict the heat transfer development downstream of support grids. In addition, circumferential variations in heat transfer coefficients result in hot streaks that develop on the rods downstream of split-vane pair support grids.

  1. Cooperative learning in science: intervention in the secondary school

    Science.gov (United States)

    Topping, K. J.; Thurston, A.; Tolmie, A.; Christie, D.; Murray, P.; Karagiannidou, E.

    2011-04-01

    The use of cooperative learning in secondary school is reported - an area of considerable concern given attempts to make secondary schools more interactive and gain higher recruitment to university science courses. In this study the intervention group was 259 pupils aged 12-14 years in nine secondary schools, taught by 12 self-selected teachers. Comparison pupils came from both intervention and comparison schools (n = 385). Intervention teachers attended three continuing professional development days, in which they received information, engaged with resource packs and involved themselves in cooperative learning. Measures included both general and specific tests of science, attitudes to science, sociometry, self-esteem, attitudes to cooperative learning and transferable skills (all for pupils) and observation of implementation fidelity. There were increases during cooperative learning in pupil formulation of propositions, explanations and disagreements. Intervened pupils gained in attainment, but comparison pupils gained even more. Pupils who had experienced cooperative learning in primary school had higher pre-test scores in secondary education irrespective of being in the intervention or comparison group. On sociometry, comparison pupils showed greater affiliation to science work groups for work, but intervention pupils greater affiliation to these groups at break and out of school. Other measures were not significant. The results are discussed in relation to practice and policy implications.

  2. Cooperative Path-Planning for Multi-Vehicle Systems

    Directory of Open Access Journals (Sweden)

    Qichen Wang

    2014-11-01

    Full Text Available In this paper, we propose a collision avoidance algorithm for multi-vehicle systems, which is a common problem in many areas, including navigation and robotics. In dynamic environments, vehicles may become involved in potential collisions with each other, particularly when the vehicle density is high and the direction of travel is unrestricted. Cooperatively planning vehicle movement can effectively reduce and fairly distribute the detour inconvenience before subsequently returning vehicles to their intended paths. We present a novel method of cooperative path planning for multi-vehicle systems based on reinforcement learning to address this problem as a decision process. A dynamic system is described as a multi-dimensional space formed by vectors as states to represent all participating vehicles’ position and orientation, whilst considering the kinematic constraints of the vehicles. Actions are defined for the system to transit from one state to another. In order to select appropriate actions whilst satisfying the constraints of path smoothness, constant speed and complying with a minimum distance between vehicles, an approximate value function is iteratively developed to indicate the desirability of every state-action pair from the continuous state space and action space. The proposed scheme comprises two phases. The convergence of the value function takes place in the former learning phase, and it is then used as a path planning guideline in the subsequent action phase. This paper summarizes the concept and methodologies used to implement this online cooperative collision avoidance algorithm and presents results and analysis regarding how this cooperative scheme improves upon two baseline schemes where vehicles make movement decisions independently.

  3. EPR studies of cooperative binding of Cu (II) to hemoglobin

    International Nuclear Information System (INIS)

    Louro, S.R.W.; Tabak, M.

    1983-07-01

    The investigation of the relative affinities of the two pairs of hemoglobin copper sites by monitoring the EPR spectra of the complexes formed by the reaction of copper with deoxyhemoglobin is reported. A model in which two sites are assumed to accept copper ions in a noncooperative way is not able to predict the experimental results. Thus it is conclude that the binding of these ions to hemoglobin is a cooperative phenomenon. (Author) [pt

  4. Microbial interspecies electron transfer via electric currents through conductive minerals

    Science.gov (United States)

    Kato, Souichiro; Hashimoto, Kazuhito; Watanabe, Kazuya

    2012-01-01

    In anaerobic biota, reducing equivalents (electrons) are transferred between different species of microbes [interspecies electron transfer (IET)], establishing the basis of cooperative behaviors and community functions. IET mechanisms described so far are based on diffusion of redox chemical species and/or direct contact in cell aggregates. Here, we show another possibility that IET also occurs via electric currents through natural conductive minerals. Our investigation revealed that electrically conductive magnetite nanoparticles facilitated IET from Geobacter sulfurreducens to Thiobacillus denitrificans, accomplishing acetate oxidation coupled to nitrate reduction. This two-species cooperative catabolism also occurred, albeit one order of magnitude slower, in the presence of Fe ions that worked as diffusive redox species. Semiconductive and insulating iron-oxide nanoparticles did not accelerate the cooperative catabolism. Our results suggest that microbes use conductive mineral particles as conduits of electrons, resulting in efficient IET and cooperative catabolism. Furthermore, such natural mineral conduits are considered to provide ecological advantages for users, because their investments in IET can be reduced. Given that conductive minerals are ubiquitously and abundantly present in nature, electric interactions between microbes and conductive minerals may contribute greatly to the coupling of biogeochemical reactions. PMID:22665802

  5. Majorana surface modes of nodal topological pairings in spin-3/2 semimetals

    Science.gov (United States)

    Yang, Wang; Xiang, Tao; Wu, Congjun

    2017-10-01

    When solid state systems possess active orbital-band structures subject to spin-orbit coupling, their multicomponent electronic structures are often described in terms of effective large-spin fermion models. Their topological structures of superconductivity are beyond the framework of spin singlet and triplet Cooper pairings for spin-1/2 systems. Examples include the half-Heusler compound series of RPtBi, where R stands for a rare-earth element. Their spin-orbit coupled electronic structures are described by the Luttinger-Kohn model with effective spin-3/2 fermions and are characterized by band inversion. Recent experiments provide evidence to unconventional superconductivity in the YPtBi material with nodal spin-septet pairing. We systematically study topological pairing structures in spin-3/2 systems with the cubic group symmetries and calculate the surface Majorana spectra, which exhibit zero energy flat bands, or, cubic dispersion depending on the specific symmetry of the superconducting gap functions. The signatures of these surface states in the quasiparticle interference patterns of tunneling spectroscopy are studied, which can be tested in future experiments.

  6. Assuring nuclear energy's future through international co-operation

    International Nuclear Information System (INIS)

    Upson, P.

    1999-01-01

    It is invited lecture as the introduction to the sixt international meeting entitled Nuclear Energy in Central Europe. Good commercial operation, public information and education are needed to win the confidence of the public, and to attract young people to take over the industry's founding generation. Stimulating international co-operation and transfer of best practices can assure this happens across the whole of the Europian nuclear industry

  7. Heat transfer enhancement in heat exchangers by longitudinal vortex generators

    International Nuclear Information System (INIS)

    Guntermann, T.; Fiebig, M.; Mitra, N.K.

    1990-01-01

    In this paper heat transfer enhancement and flow losses are computed for the interaction of a laminar channel flow with a pair of counterrotating longitudinal vortices generated by a pair of delta-winglets punched out of the channel wall. The geometry simulates an element of a fin-plate or fin-tube heat exchanger. The structure of the vortex flow and temperature distribution, the local heat transfer coefficients and the local flow losses are discussed for a sample case. For a Reynolds number of Re d = 1000 and a vortex generator angle of attack of β = 25 degrees heat transfer is enhanced locally by more than 300% and in the mean by 50%. These values increase further with Re and β

  8. Food irradiation: Technology transfer in Asia, practical experiences

    Science.gov (United States)

    Kunstadt, Peter; Eng, P.

    1993-10-01

    Nordion International Inc., in cooperation with the Thai Office of Atomic Energy for Peace (OAEP) and the Canadian International Development Agency (CIDA) recently completed a unique food irradiation technology transfer project in Thailand. This complete food irradiation technology transfer project included the design and construction of an automatic multipurpose irradiation facility as well as the services of construction and installation management and experts in facility operation, maintenance and training. This paper provides an insight into the many events that led to the succesful conclusion of the world's first complete food irradiation technology transfer project.

  9. Food irradiation: technology transfer in Asia, practical experiences

    International Nuclear Information System (INIS)

    Kunstadt, P.

    1993-01-01

    Nordion International Inc., in cooperation with the Thai Office of Atomic Energy for Peace (OAEP) and the Canadian International Development Agency (CIDA) recently completed a unique food irradiation technology transfer project in Thailand. This complete food irradiation technology transfer project included the design and construction of an automatic multipurpose irradiation facility as well as the services of construction and installation management and experts in facility operation, maintenance and training. This paper provides an insight into the many events that led to the successful conclusion of the world's first complete food irradiation technology transfer project. (Author)

  10. Technology transfer for development

    International Nuclear Information System (INIS)

    Abraham, D.

    1990-07-01

    The IAEA has developed a multifaceted approach to ensure that assistance to Member States results in assured technology transfer. Through advice and planning, the IAEA helps to assess the costs and benefits of a given technology, determine the basic requirements for its efficient use in conditions specific to the country, and prepare a plan for its introduction. This report describes in brief the Technical Co-operation Programmes

  11. To cooperate or not to cooperate

    DEFF Research Database (Denmark)

    Wessels, Josepha Ivanka

    To Cooperate or not to Cooperate...? discusses results of a research project to study the rehabilitation of 1500-year old water tunnels, so called "qanats", in Syria. Communities all over the world are using traditional technologies to extract drinkingwater, irrigate their lands and feed...... their livestock. But these often sustainable and ancient ways to make use of groundwater are in rapid decline worldwide. A research project started in 1999 to study the rehabilitation of 1500-year old water tunnels called "qanats"in Syria. To Cooperate or not to Cooperate...? discusses results and outcomes...

  12. Evaluation of a "no-cost" Internet technology-based system for teleradiology and co-operative work.

    Science.gov (United States)

    Bergh, B; Schlaefke, A; Pietsch, M; García, I; Vogl, T J

    2003-02-01

    The aim of this study was to assess the suitability of a no-cost system based on standard Internet technology components for teleradiology. The system was composed of free software (communication, DICOM viewer, compression) and standard off-the-shelf hardware components. For different image (CR, CT, MR) and network types (LAN and ISDN) the File Transfer, Audio and Video Conference, and Co-operative Work properties were examined and compared with the literature referring to standard complete packages and dedicated teleradiology systems. The main advantages of the no-cost system are: price; ease of use; independence from specific hardware; and potential connection to any possible partner. The performance of the File Transfer and the Audio and Video Conference was comparable to the other system groups with slight disadvantages in the usability. For Co-operative Work the employed "application sharing" technology does not meet the clinical requirements, which applies identically to the standard complete packages. Here the specialized systems prove superior, although they are proprietary. With minimal restraints the evaluated no-cost solution can be used for File Transfer and Conference scenarios. The usage for Co-operative Work with ISDN is not recommended, unless for the purpose of gaining experience or when dealing with small amounts of cases or images.

  13. Evaluation of a ''no-cost'' Internet technology-based system for teleradiology and Co-operative Work

    International Nuclear Information System (INIS)

    Bergh, B.; Schlaefke, A.; Pietsch, M.; Garcia, I.; Vogl, T.J.

    2003-01-01

    The aim of this study was to assess the suitability of a no-cost system based on standard Internet technology components for teleradiology. The system was composed of free software (communication, DICOM viewer, compression) and standard off-the-shelf hardware components. For different image (CR, CT, MR) and network types (LAN and ISDN) the File Transfer, Audio and Video Conference, and Co-operative Work properties were examined and compared with the literature referring to standard complete packages and dedicated teleradiology systems. The main advantages of the no-cost system are: price; ease of use; independence from specific hardware; and potential connection to any possible partner. The performance of the File Transfer and the Audio and Video Conference was comparable to the other system groups with slight disadvantages in the usability. For Co-operative Work the employed ''application sharing'' technology does not meet the clinical requirements, which applies identically to the standard complete packages. Here the specialized systems prove superior, although they are proprietary. With minimal restraints the evaluated no-cost solution can be used for File Transfer and Conference scenarios. The usage for Co-operative Work with ISDN is not recommended, unless for the purpose of gaining experience or when dealing with small amounts of cases or images. (orig.)

  14. Coordination and collective performance: Cooperative goals boost interpersonal synchrony and task outcomes

    Directory of Open Access Journals (Sweden)

    Jamie S. Allsop

    2016-09-01

    Full Text Available Whether it be a rugby team or a rescue crew, ensuring peak group performance is a primary goal during collective activities. In reality however, groups often suffer from productivity losses that can lead to less than optimal outputs. Where researchers have focused on this problem, inefficiencies in the way team members coordinate their efforts has been identified as one potent source of productivity decrements. Here we set out to explore whether performance on a simple object movement task is shaped by the spontaneous emergence of interpersonally coordinated behavior. Forty-six pairs of participants were instructed to either compete or cooperate in order to empty a container of approximately 100 small plastic balls as quickly and accurately as possible. Each trial was recorded to video and a frame-differencing approach was employed to estimate between-person coordination. The results revealed that cooperative pairs coordinated to a greater extent than their competitive counterparts. Furthermore, coordination, as well as movement regularity were positively related to accuracy, an effect that was most prominent when the task was structured such that opportunities to coordinate were restricted. These findings are discussed with regard to contemporary theories of coordination and collective performance.

  15. Technology transfer - north/south

    Energy Technology Data Exchange (ETDEWEB)

    Ercan, Y [Gazi University, Ankara (Turkey). Faculty of Engineering and Architecture

    1991-01-01

    Technology transfer is needed to the developing countries in the fields of fuel, combustion equipment, and operations to maximise combustion efficiency and minimise the harmful emissions. Channels of technology transfer available include: direct foreign investment, joint ventures, patent and licence purchases, industrial co-operation and technical aid, importation of technical goods, and turn-key projects. Dependency on totally imported technology and equipment both in boilers and flue gas treatment systems, however, results in high investment costs and may limit extensive use of power plants based on coal. If technologies to improve the efficiencies and emission behaviour of coal utilizing facilities are transferred to developing countries, a business scheme mutually beneficial both to the developing countries and the coal producing countries can be reached, which will boost the industrialization of the developing countries. 11 refs., 3 figs., 1 tab.

  16. Time-resolved statistics of photon pairs in two-cavity Josephson photonics

    Energy Technology Data Exchange (ETDEWEB)

    Dambach, Simon; Kubala, Bjoern; Ankerhold, Joachim [Institute for Complex Quantum Systems and IQST, Ulm University (Germany)

    2017-06-15

    We analyze the creation and emission of pairs of highly nonclassical microwave photons in a setup where a voltage-biased Josephson junction is connected in series to two electromagnetic oscillators. Tuning the external voltage such that the Josephson frequency equals the sum of the two mode frequencies, each tunneling Cooper pair creates one additional photon in both of the two oscillators. The time-resolved statistics of photon emission events from the two oscillators is investigated by means of single- and cross-oscillator variants of the second-order correlation function g{sup (2)}(τ) and the waiting-time distribution w(τ). They provide insight into the strongly correlated quantum dynamics of the two oscillator subsystems and reveal a rich variety of quantum features of light including strong antibunching and the presence of negative values in the Wigner function. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. First tests of twisted-pair HTS 1 kA range cables for use in superconducting links

    CERN Document Server

    Ballarino, A; Hurte, J; Sitko, M; Willering, G

    2011-01-01

    The requirement at CERN for 1 kA range High Temperature Superconducting (HTS) cables optimized for long electrical transfer has led to the design and assembly of a novel type of cable that can be made from pre-reacted MgB2, Bi-2223 or YBCO tapes. The cable consists of an assembly of twisted pairs, each of which is made from three superconducting tapes with the required copper stabilizer. The twisted pair cable is designed to transfer a DC current of ± 600 A in helium gas environment. The paper reports on the results of the electrical tests performed on twisted-pair cables of identical structure and made from commercially available MgB2, Bi-2223 and YBCO tapes. The twist pitch of the cables is adapted to match the mechanical properties of the different superconductors. Critical current tests were performed at both liquid helium and liquid nitrogen temperature. The electrical performance of several cables made from different conductors is reported and compared.

  18. Successful transfer of nuclear technology by the aid of scientific and technological cooperation

    International Nuclear Information System (INIS)

    Laue, H.J.; Nentwich, D.

    1977-01-01

    The good results obtained with the nuclear power plants in operation and especially the world-wide increase of prices of fossile energy sources have caused many developing countries to take a special interest in the use of nuclear energy for a long-term energy supply and the set-up and extension of their own industry as a means to ameliorate the living standard. On the other hand, the pre-conditions for the preparation, planning and the economical use of nuclear energy which cannot be realized by simply purchasing a modern nuclear power station are lacking in most of these countries. A timely and careful preparation is therefore imperative to realize the plan of introducing nuclear energy. This can certainly be done only with the help of international support in the frame of bilateral or multilateral agreements. Without going into details of the variety of possibilities within international organizations, such as IAEA, this paper shows examples of successfully carried out bilateral cooperation between the Federal Republic of Germany and a number of developing countries of very different characteristics. A basic requirement for a successful transfer of technology is a high knowledge level of the indigenous scientists and engineers. Therefore, programmes for training and education and for information exchange in the Federal Republic of Germany as well as in the partner country are presented. Based on these, the means and methods of planning, performance and quality assurance are explained by practical examples and are related to the progress achieved in the use of nuclear energy and in establishing a national industry in the developing countries. Finally, the achieved results are critically analyzed, recommendations for future projects with other countries are given, and the successful interconnection of bilateral efforts with multilaterial projects of IAEA, UNDP, etc., is shown as a particularly promising method

  19. Learning to Cooperate: The Evolution of Social Rewards in Repeated Interactions.

    Science.gov (United States)

    Dridi, Slimane; Akçay, Erol

    2018-01-01

    Understanding the behavioral and psychological mechanisms underlying social behaviors is one of the major goals of social evolutionary theory. In particular, a persistent question about animal cooperation is to what extent it is supported by other-regarding preferences-the motivation to increase the welfare of others. In many situations, animals adjust their behaviors through learning by responding to the rewards they experience as a consequence of their actions. Therefore, we may ask whether learning in social situations can be driven by evolved other-regarding rewards. Here we develop a mathematical model in order to ask whether the mere act of cooperating with a social partner will evolve to be inherently rewarding. Individuals interact repeatedly in pairs and adjust their behaviors through reinforcement learning. We assume that individuals associate with each game outcome an internal reward value. These perceived rewards are genetically evolving traits. We find that conditionally cooperative rewards that value mutual cooperation positively but the sucker's outcome negatively tend to be evolutionarily stable. Purely other-regarding rewards can evolve only under special parameter combinations. On the other hand, selfish rewards that always lead to pure defection are also evolutionarily successful. These findings are consistent with empirical observations showing that humans tend to display conditionally cooperative behavior and also exhibit a diversity of preferences. Our model also demonstrates the need to further integrate multiple levels of biological causation of behavior.

  20. The role of autoshaping in cooperative two-player games between starlings.

    Science.gov (United States)

    Reboreda, J C; Kacelnik, A

    1993-07-01

    We report a study of the behavior of starlings in laboratory situations inspired by the "prisoner's dilemma." Our purpose is to investigate some possible mechanisms for the maintenance of cooperation by reciprocity and to investigate the process of autoshaping at a trial-by-trial level. In Experiment 1, pairs of starlings housed in adjacent cages played a discrete-trial "game" in which food could be obtained only by "cooperation." In this game, pecking at a response key eliminated the opportunity to obtain food but produced food for the partner. If neither bird pecked, neither had the opportunity to obtain food in that trial. Some level of cooperation persisted for several sessions whether the birds had been pretrained for a high or low probability of pecking at the key. The probability of a cooperative response was higher after trials in which the partner responded (and a reward was obtained) than after trials in which neither bird responded (and no reward was obtained), but the probability of a response was even higher after trials in which the same bird had responded, even though no reward was obtained by the actor in these trials. This behavior did not require visual presence of another player, because similar results were obtained in Experiment 2 (a replicate of Experiment 1 in which the members of the pair could not see each other) and in Experiment 3, a game in which each starling played with a computer responding with "tit for tat." Using an omission schedule, in which food was given in all trials in which the bird did not peck, Experiment 4 showed that pecking could be maintained by autoshaping. In this experiment, overall probability of pecking decreased with experience, due to a drop in the tendency to peck in consecutive trials. The probability of pecking in trials following a reinforced trial did not decrease with experience. An implementation of the Rescorla-Wagner model for this situation was capable of reproducing molar, but not molecular, aspects

  1. Nanoscale strain-induced pair suppression as a vortex-pinning mechanism in high-temperature superconductors

    International Nuclear Information System (INIS)

    Llordes, Anna; Palau, A.; Gazquez, J.; Coll, M.; Vlad, R.; Pomar, A.; Arbiol, Jordi; Guzman, Roger; Ye, S.; Rouco, V.; Sandiumenge, Felip; Ricart, Susagna; Puig, Teresa; Varela del Arco, Maria; Chataigner, D.; Vanacken, J.; Gutierrez, J.; Moschalkov, V.; Deutscher, G.; Magen Dominguez, Cesar; Obradors, Xavier

    2012-01-01

    Boosting large-scale superconductor applications require nanostructured conductors with artificial pinning centres immobilizing quantized vortices at high temperature and magnetic fields. Here we demonstrate a highly effective mechanism of artificial pinning centers in solution-derived high-temperature superconductor nanocomposites through generation of nanostrained regions where Cooper pair formation is suppressed. The nanostrained regions identified from transmission electron microscopy devise a very high concentration of partial dislocations associated with intergrowths generated between the randomly oriented nanodots and the epitaxial YBa 2 Cu 3 O 7 matrix. Consequently, an outstanding vortex-pinning enhancement correlated to the nanostrain is demonstrated for four types of randomly oriented nanodot, and a unique evolution towards an isotropic vortex-pinning behaviour, even in the effective anisotropy, is achieved as the nanostrain turns isotropic. We suggest a new vortex-pinning mechanism based on the bond-contraction pairing model, where pair formation is quenched under tensile strain, forming new and effective core-pinning regions.

  2. Contribution of international cooperation in achieving the Romanian nuclear power objectives

    International Nuclear Information System (INIS)

    Diaconu, Daniela

    2002-01-01

    The international cooperation implied by the Romanian nuclear power program has on the short term the goal of supporting the Romanian effort of obtaining new nuclear fuels, improving the radioactive waste management, developing the technology and software transfer, training of Romanian researchers and participations in international projects. On long term the international cooperation is aiming at rising the scientific standards and the degree of global integration of Romanian research and technology. This policy is supported also by the agreements convened with different international organizations as for instance 'The Agreement for Nuclear Safety' or 'Common agreement for safe management of spent fuel and radioactive waste'. The INR at Pitesti and CITON - Bucharest are involved in works for cooperation technical projects supported by IAEA Vienna aiming at the nuclear safe and safeguard and power programs. At present underway are research contracts concerning the CANDU pressure tube, the corrosion in the primary cooling circuit of the CANDU reactors, as well as, the behavior under irradiation and intermediate disposal of oxide fuels. In the frame of IAEA assisted technical programs the TRIGA reactor of INR Pitesti is transferred from HEU to LEU fuels, new technologies for using recovered uranium and slightly enriched uranium fuels are developed, as well as a data acquisition system with advanced on-line characteristics. The cooperation between INR Pitesti and AECL Canada comprised in the frame of the 1998 agreement is oriented towards three fields of common interest: nuclear safety, nuclear fuel and management of in-service life of NPPs. Already transferred were computer codes from AECL devoted to accident analysis (WIMS, CATHENA and ELOCA) which were implemented and reproduced accurately all the test cases provided by AECL. For installing these codes specialists from our institute participated in training courses, on-the-job training, as well as, in validation

  3. 75 FR 10319 - Cooper Tools-Sumter, Cooper Tools Divisions, a Subsidiary of Cooper Industries, Inc., Including...

    Science.gov (United States)

    2010-03-05

    ... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-71,602] Cooper Tools--Sumter, Cooper Tools Divisions, a Subsidiary of Cooper Industries, Inc., Including On-Site Leased Workers From... January 26, 2010, applicable to workers of Cooper Tools--Sumter, Cooper Tools Division, a subsidiary of...

  4. Advances in electron transfer chemistry

    CERN Document Server

    Mariano, Patrick S

    1995-01-01

    Advances in Electron Transfer Chemistry, Volume 4 presents the reaction mechanisms involving the movement of single electrons. This book discusses the electron transfer reactions in organic, biochemical, organometallic, and excited state systems. Organized into four chapters, this volume begins with an overview of the photochemical behavior of two classes of sulfonium salt derivatives. This text then examines the parameters that control the efficiencies for radical ion pair formation. Other chapters consider the progress in the development of parameters that control the dynamics and reaction p

  5. Stability of the Superconducting d-Wave Pairing Toward the Intersite Coulomb Repulsion in CuO_2 Plane

    Science.gov (United States)

    Val'kov, V. V.; Dzebisashvili, D. M.; Korovushkin, M. M.; Barabanov, A. F.

    2018-06-01

    Taking into account the real crystalline structure of the CuO_2 plane and the strong spin-fermion coupling, we study the influence of the intersite Coulomb repulsion between holes on the Cooper instability of the spin-polaron quasiparticles in cuprate superconductors. The analysis shows that only the superconducting d-wave pairing is implemented in the whole region of doping, whereas the solutions of the self-consistent equations for the s-wave pairing are absent. It is shown that intersite Coulomb interaction V_1 between the holes located at the nearest oxygen ions does not affect the d-wave pairing, because its Fourier transform V_q vanishes in the kernel of the corresponding integral equation. The intersite Coulomb interaction V_2 of quasiparticles located at the next-nearest oxygen ions does not vanish in the integral equations, however, but it is also shown that the d-wave pairing is robust toward this interaction for physically reasonable values of V_2.

  6. Pair potentials and structure factors of liquid alkali metals

    International Nuclear Information System (INIS)

    Kumaravadivel, R.; Tosi, M.P.

    1984-03-01

    Measured structure factors of liquid alkali metals are examined in the framework of screened-pair-potentials theory. Information on the main attractive well in the effective pair potential is obtained from the structural data by an approximate method stemming from an optimized random phase treatment of the indirect ion-ion attraction. The results are compared with a variety of theoretical pair potentials in the cases of sodium and potassium, after a test of the method against computer simulation data on a model for rubidium. Results for the other alkali metals are also given and discussed. The small-angle scattering region is then examined in considerable detail, with special attention to the possibility of a linear term in a series expansion of the structure factor at very small momentum transfer. Although sensitivity to both the bare electron-ion coupling and the local field factor in the screening function is demonstrated and analyzed, no linear term of the magnitude reported in recent X-ray diffraction experiments is found in the present theoretical framework. (author)

  7. EFEKTIVITAS PENGGUNAAN METODE THINK PAIR SHARE DALAM PEMBELAJARAN EKONOMI POKOK BAHASAN PEMBENTUKAN HARGA PASAR DI SMP

    Directory of Open Access Journals (Sweden)

    Joko Widodo

    2011-06-01

    Full Text Available The result of teaching-learning by using Think Pair Share method can improve the students’ activities. It can be seen from the steps to apply the Think Pair Share method that focused on student-centre. Think pair share learning has a simple structure, as a basic of the development ‘cooperative class’ which can help the learning process actively for students, thus it can improve the students’ study result. Students actively can show their ability to discuss and share and express the answer of questions in front of the class. Teachers in teaching- learning process by using think pair share method acted as mediator, facilitator and motivator. It is different with conventional teaching-learning process which focused on teacher-center. Students were passive in teaching-learning process. Students tended to be bored if the teacher was lack to give motivation for students to pay attention to the teacher. Thus, the using of think pair share would be more effective if we see on how the students interaction in learning process. Teacher can vary think pair share with conventional method or other method to improve the students’ activities in learning process, therefore the students’ result study will be increased.   Keywords: Think-pair-share, the increase of result study.

  8. EFEKTIVITAS PENGGUNAAN METODE THINK PAIR SHARE DALAM PEMBELAJARAN EKONOMI POKOK BAHASAN PEMBENTUKAN HARGA PASAR DI SMP

    Directory of Open Access Journals (Sweden)

    Joko Widodo

    2007-06-01

    Full Text Available The result of teaching-learning by using Think Pair Share method can improve the students’ activities. It can be seen from the steps to apply the Think Pair Share method that focused on student-centre. Think pair share learning has a simple structure, as a basic of the development ‘cooperative class’ which can help the learning process actively for students, thus it can improve the students’ study result. Students actively can show their ability to discuss and share and express the answer of questions in front of the class. Teachers in teaching- learning process by using think pair share method acted as mediator, facilitator and motivator. It is different with conventional teaching-learning process which focused on teacher-center. Students were passive in teaching-learning process. Students tended to be bored if the teacher was lack to give motivation for students to pay attention to the teacher. Thus, the using of think pair share would be more effective if we see on how the students interaction in learning process. Teacher can vary think pair share with conventional method or other method to improve the students’ activities in learning process, therefore the students’ result study will be increased.   Keywords: Think-pair-share, the increase of result study.

  9. New Values of Cross-Talk Parameters for Twisted Pair Model

    OpenAIRE

    Milos Kozak; Lukas Cepa; Jiri Vodrazka

    2010-01-01

    Near-end Crosstalk (NEXT) and Far-end Crosstalk (FEXT) of unshielded twisted pair (UTP) cable are the main factors limiting the information capacity in data transmission. Crosstalk depends mostly on the frequency. Frequency dependent transfer functions and crosstalk attenuation may be obtained by measurement, but for the analytical description of the transmission channel's parameters is useful to define functions modelling the crosstalk. The paper describes the measuri...

  10. Pair condensation and bound states in fermionic systems

    International Nuclear Information System (INIS)

    Sedrakian, Armen; Clark, John W.

    2006-01-01

    We study the finite temperature-density phase diagram of an attractive fermionic system that supports two-body (dimer) and three-body (trimer) bound states in free space. Using interactions characteristic for nuclear systems, we obtain the critical temperature T c2 for the superfluid phase transition and the limiting temperature T c3 for the extinction of trimers. The phase diagram features a Cooper-pair condensate in the high-density, low-temperature domain which, with decreasing density, crosses over to a Bose condensate of strongly bound dimers. The high-temperature, low-density domain is populated by trimers whose binding energy decreases toward the density-temperature domain occupied by the superfluid and vanishes at a critical temperature T c3 >T c2

  11. Steering population transfer of the Na2 molecule by an ultrashort pulse train

    Science.gov (United States)

    Niu, Dong-Hua; Wang, Shuo; Zhan, Wei-Shen; Tao, Hong-Cai; Wang, Si-Qi

    2018-05-01

    We theoretically investigate the complete population transfer among quantum states of the Na2 molecule using ultrashort pulse trains using the time-dependent wave packet method. The population accumulation of the target state can be steered by controlling the laser parameters, such as the variable pulse pairs, the different pulse widths, the time delays and the repetition period between two contiguous pulses; in particular, the pulse pairs and the pulse widths have a great effect on the population transfer. The calculations show that the ultrashort pulse train is a feasible solution, which can steer the population transfer from the initial state to the target state efficiently with lower peak intensities.

  12. Entanglement transfer from microwaves to diamond NV centers

    Science.gov (United States)

    Gomez, Angela V.; Rodriguez, Ferney J.; Quiroga, Luis

    2014-03-01

    Strong candidates to create quantum entangled states in solid-state environments are the nitrogen-vacancy (NV) defect centers in diamond. By the combination of radiation from different wavelength (optical, microwave and radio-frequency), several protocols have been proposed to create entangled states of different NVs. Recently, experimental sources of non-classical microwave radiation have been successfully realized. Here, we consider the entanglement transfer from spatially separated two-mode microwave squeezed (entangled) photons to a pair of NV centers by exploiting the fact that the spin triplet ground state of a NV has a natural splitting with a frequency on the order of GHz (microwave range). We first demonstrate that the transfer process in the simplest case of a single pair of spatially separated NVs is feasible. Moreover, we proceed to extend the previous results to more realistic scenarios where 13C nuclear spin baths surrounding each NV are included, quantifying the degradation of the entanglement transfer by the dephasing/dissipation effects produced by the nuclear baths. Finally, we address the issue of assessing the possibility of entanglement transfer from the squeezed microwave light to two nuclear spins closely linked to different NV center electrons. Facultad de Ciencias Uniandes.

  13. Cooperative emission in ion implanted Yb:YAG waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez, G V; Desirena, H; De la Rosa, E [Centro de Investigaciones en Optica, Loma del Bosque 115, Lomas del Campestre, 37150 Leon, Guanajuato (Mexico); Flores-Romero, E; Rickards, J; Trejo-Luna, R [Instituto de Fisica, UNAM, Apartado Postal 20364, 01000 Mexico, D. F. (Mexico); Marquez, H, E-mail: gvvazquez@cio.mx [Departamento de Optica, CICESE, Km 107 Carr. Tijuana-Ensenada, 22860 Ensenada, B. C. (Mexico)

    2011-01-01

    In this work, we report the analysis of spectroscopic properties of waveguides fabricated by ion implantation in YAG doped with Yb{sup 3+} ions. Three emission bands were detected in the blue, green and red regions under 970-nm excitation. The strong blue-green emission can be explained by a cooperative process between ytterbium ion pairs, leading to emission centered at 514 nm. The additional blue bands as well as green and red emission bands are attributed to the presence of Tm{sup 3+} and Er{sup 3+} traces. The results include absorption and emission curves as well as decay time rates.

  14. Cooperative emission in ion implanted Yb:YAG waveguides

    International Nuclear Information System (INIS)

    Vazquez, G V; Desirena, H; De la Rosa, E; Flores-Romero, E; Rickards, J; Trejo-Luna, R; Marquez, H

    2011-01-01

    In this work, we report the analysis of spectroscopic properties of waveguides fabricated by ion implantation in YAG doped with Yb 3+ ions. Three emission bands were detected in the blue, green and red regions under 970-nm excitation. The strong blue-green emission can be explained by a cooperative process between ytterbium ion pairs, leading to emission centered at 514 nm. The additional blue bands as well as green and red emission bands are attributed to the presence of Tm 3+ and Er 3+ traces. The results include absorption and emission curves as well as decay time rates.

  15. Sign of the electron exchange coupling in random radical encounter pairs in solution

    International Nuclear Information System (INIS)

    Thurnauer, M.C.; Chiu, T.M.; Trifunac, A.D.

    1985-01-01

    An important parameter in the study of reacting radical systems is the electron exchange interaction, J. The properties of interest are the sign and magnitude of J, and its functional dependence on distance between radicals. One source of information about J is from understanding the Chemically Induced Dynamic Electron Polarization (CIDEP) which is observed in the EPR spectra of reactive radical systems. For radicals reacting in solution to form new covalent bonds, it has generally been found that J O. It is suggested that F-pairs react at a separation greater than that at which spin correlated (geminate) pairs of the same radicals are formed, so that the intervening solvent molecules become involved in the exchange interaction giving rise to J>O via some sort of superexchange process. This is an interesting proposition since superexchange via solvent molecules may play a role in rates of long-distance electron transfer reactions and in the electron transfer reactions of photosynthesis. However, the model suggested runs contrary to all F-air radicals are produced. In order to clarify this important point, the authors present here a definitive study in which we examine several systems of radgenerated independently (exclusive F-pairs) by pulsed laser photolysis and pulsed radiolicals generatedysis in aqueous, alcoholic and hydrocarbon solvents

  16. Teaching calculus using module based on cooperative learning strategy

    Science.gov (United States)

    Arbin, Norazman; Ghani, Sazelli Abdul; Hamzah, Firdaus Mohamad

    2014-06-01

    The purpose of the research is to evaluate the effectiveness of a module which utilizes the cooperative learning for teaching Calculus for limit, derivative and integral. The sample consists of 50 semester 1 students from the Science Programme (AT 16) Sultan Idris Education University. A set of questions of related topics (pre and post) has been used as an instrument to collect data. The data is analyzed using inferential statistics involving the paired sample t-test and the independent t-test. The result shows that students have positive inclination towards the modulein terms of understanding.

  17. A Project in Support of Nuclear Technology Cooperation

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Deok Ku; Kim, Kyoung Pyo; Ko, Young Chel [and others

    2006-12-15

    Establish strategies of international cooperation in an effect to promote our nation's leading role in international society, to form the foundation for the effective transfer of nuclear technology to developing countries, and to cope with the rapidly changing international nuclear climate. Using the INIS output data, it has provided domestic users with searching. Establish the integrated management system of information resources and to automate business flow and to improve business productivity through efficient information sharing.

  18. PEMBELAJARAN THINK-PAIR-SHARE, KETERAMPILAN METAKOGNITIF, DAN HASIL BELAJAR KOGNITIF SISWA SMA

    Directory of Open Access Journals (Sweden)

    Sri Amnah S.

    2012-05-01

    Full Text Available Abstract: Think-Pair-Share Learning, Meta-cognitive Skills and Cognitive Learning Outcomes. The study investigates the effects of meta-cognitive skills based Think-Pair-Share cooperative learning on meta-cognitive skills and cognitive learning outcomes of 11th grade students of Senior High Schools in Pekanbaru. The sample consists of 11th grade students of SMA 9 as an experiment group and 11th grade students SMA 10 as a control group. Based on analyzing the data using ANCOVA, the results show that there is a signifi­cant difference in meta-cognitive skills and cognitive learning outcomes of the students in the experimental and the control groups, and there is no significant difference between students who have high and low academic levels in their meta-cognitive skills and cognitive learning outcomes. Abstrak: Pembelajaran Think-Pair-Share, Keterampilan Metakognitif, dan Hasil Belajar Kognitif Siswa SMA. Penelitian ini bertujuan mengukur pengaruh pembela­jaran koperatif Think-Pair-Share terha­dap keterampilan metakognitif dan hasil belajar kognitif siswa SMA. Sampel dipilih secara acak dari popu­lasi 13 SMA di Pekanbaru. Dengan menggunakan ANAKOVA, hasilnya menunjukkan bahwa terdapat per­bedaan yang nyata keterampilan metakognitif dan hasil belajar kognitif siswa di kelompok eksperimental dan kelompok control, dan tidak ada perbedaan yang nyata antara siswa berkemampuan akademik tinggi dan akademik rendah pada keterampilan metakognitif dan hasil belajar kognitifnya.

  19. Energy-harvesting in cooperative AF relaying networks over log-normal fading channels

    KAUST Repository

    Rabie, Khaled M.; Salem, Abdelhamid; Alsusa, Emad; Alouini, Mohamed-Slim

    2016-01-01

    Energy-harvesting (EH) and wireless power transfer are increasingly becoming a promising source of power in future wireless networks and have recently attracted a considerable amount of research, particularly on cooperative two-hop relay networks in Rayleigh fading channels. In contrast, this paper investigates the performance of wireless power transfer based two-hop cooperative relaying systems in indoor channels characterized by log-normal fading. Specifically, two EH protocols are considered here, namely, time switching relaying (TSR) and power splitting relaying (PSR). Our findings include accurate analytical expressions for the ergodic capacity and ergodic outage probability for the two aforementioned protocols. Monte Carlo simulations are used throughout to confirm the accuracy of our analysis. The results show that increasing the channel variance will always provide better ergodic capacity performance. It is also shown that a good selection of the EH time in the TSR protocol, and the power splitting factor in the PTS protocol, is the key to achieve the best system performance. © 2016 IEEE.

  20. Energy-harvesting in cooperative AF relaying networks over log-normal fading channels

    KAUST Repository

    Rabie, Khaled M.

    2016-07-26

    Energy-harvesting (EH) and wireless power transfer are increasingly becoming a promising source of power in future wireless networks and have recently attracted a considerable amount of research, particularly on cooperative two-hop relay networks in Rayleigh fading channels. In contrast, this paper investigates the performance of wireless power transfer based two-hop cooperative relaying systems in indoor channels characterized by log-normal fading. Specifically, two EH protocols are considered here, namely, time switching relaying (TSR) and power splitting relaying (PSR). Our findings include accurate analytical expressions for the ergodic capacity and ergodic outage probability for the two aforementioned protocols. Monte Carlo simulations are used throughout to confirm the accuracy of our analysis. The results show that increasing the channel variance will always provide better ergodic capacity performance. It is also shown that a good selection of the EH time in the TSR protocol, and the power splitting factor in the PTS protocol, is the key to achieve the best system performance. © 2016 IEEE.

  1. Forms of Cooperative Learning in Language Teaching in Slovenian Language Classes at the Primary School Level

    Science.gov (United States)

    Vrhovec, Alenka Rot

    2015-01-01

    In the Slovenian language syllabus, teachers are recommended to provide a greater share of group work during class. During types of learning such as cooperative learning in smaller groups or pairs, students actively develop communicative competence. The present article presents a survey that attempted to determine whether teachers from the first…

  2. It’s Not Just Lunch: Extra-Pair Commensality Can Trigger Sexual Jealousy

    Science.gov (United States)

    Kniffin, Kevin M.; Wansink, Brian

    2012-01-01

    Do people believe that sharing food might involve sharing more than just food? To investigate this, participants were asked to rate how jealous they (Study 1) – or their best friend (Study 2) – would be if their current romantic partner were contacted by an ex-romantic partner and subsequently engaged in an array of food- and drink-based activities. We consistently find – across both men and women – that meals elicit more jealousy than face-to-face interactions that do not involve eating, such as having coffee. These findings suggest that people generally presume that sharing a meal enhances cooperation. In the context of romantic pairs, we find that participants are attuned to relationship risks that extra-pair commensality can present. For romantic partners left out of a meal, we find a common view that lunch, for example, is not “just lunch.” PMID:22792327

  3. Nuclear fuel powder transfer device

    International Nuclear Information System (INIS)

    Komono, Akira

    1998-01-01

    A pair of parallel rails are laid between a receiving portion to a molding portion of a nuclear fuel powder transfer device. The rails are disposed to the upper portion of a plurality of parallel support columns at the same height. A powder container is disposed while being tilted in the inside of the vessel main body of a transfer device, and rotational shafts equipped with wheels are secured to right and left external walls. A nuclear powder to be mixed, together with additives, is supplied to the powder container of the transfer device. The transfer device engaged with the rails on the receiving side is transferred toward the molding portion. The wheels are rotated along the rails, and the rotational shafts, the vessel main body and the powder container are rotated. The nuclear powder in the tilted powder container disposed is rotated right and left and up and down by the rotation, and the powder is mixed satisfactory when it reaches the molding portion. (I.N.)

  4. Selection of arboreal termitaria for nesting by cooperatively breeding Micronesian Kingfishers Todiramphus cinnamominus reichenbachii

    Science.gov (United States)

    Kesler, Dylan C.; Haig, Susan M.

    2005-01-01

    Limited nest-site availability appears to be an important factor in the evolution of delayed dispersal and cooperative breeding in some cavity-nesting species. The cooperatively breeding Pohnpei subspecies of Micronesian Kingfisher Todiramphus cinnamominus reichenbachii excavates nest cavities from the nests of arboreal termites Nasutitermes spp., or termitaria. In this first published description of nest-sites for this subspecies, we used surveys, remote sensing and radiotelemetry to evaluate the relationship between nest-site availability and co-operation. Results illustrate that nest termitaria are higher in the forest canopy, larger in volume and occur in areas with more contiguous canopy cover than unused termitaria. Nest termitaria were selected independently of the proximity to forest edges and territory boundaries, and we found no difference in characteristics of termitaria used by cooperative groups and breeding pairs. Logistic regression modelling indicated that termitaria with nest-like characteristics were not limited in abundance, suggesting that neither the prospects of inheriting nesting resources nor limited nest-site abundance are probable explanations for delayed dispersal in the Pohnpei subspecies of Micronesian Kingfisher.

  5. Adult sex ratios and their implications for cooperative breeding in birds.

    Science.gov (United States)

    Komdeur, Jan; Székely, Tamás; Long, Xiaoyan; Kingma, Sjouke A

    2017-09-19

    Cooperative breeding is a form of breeding system where in addition to a core breeding pair, one or more usually non-breeding individuals provide offspring care. Cooperative breeding is widespread in birds, but its origin and maintenance in contemporary populations are debated. Although deviations in adult sex ratio (ASR, the proportion of males in the adult population) have been hypothesized to influence the occurrence of cooperative breeding because of the resulting surplus of one sex and limited availability of breeding partners, this hypothesis has not been tested across a wide range of taxa. By using data from 188 bird species and phylogenetically controlled analyses, we show that cooperatively breeding species have more male-biased ASRs than non-cooperative species. Importantly, ASR predicts helper sex ratio: in species with more male-biased ASR, helper sex ratio is also more male biased. We also show that offspring sex ratios do not predict ASRs, so that the skewed ASRs emerge during the period when individuals aim to obtain a breeding position or later during adulthood. In line with this result, we found that ASR (among both cooperatively and non-cooperatively breeding species) is inversely related to sex bias in dispersal distance, suggesting that the cost of dispersal is more severe for the further-dispersing sex. As females usually disperse further in birds, this explains the generally male-biased ASR, and in combination with benefits of philopatry for males, this probably explains why ASR is more biased in cooperatively breeding species. Taken together, our results suggest that a sex bias in helping in cooperatively breeding species relates to biased ASRs. We propose that this relationship is driven by sex-specific costs and benefits of dispersal and helping, as well as other demographic factors. Future phylogenetic comparative and experimental work is needed to establish how this relationship emerges.This article is part of the themed issue 'Adult sex

  6. Cooperation and charity in spatial public goods game under different strategy update rules

    Science.gov (United States)

    Li, Yixiao; Jin, Xiaogang; Su, Xianchuang; Kong, Fansheng; Peng, Chengbin

    2010-03-01

    Human cooperation can be influenced by other human behaviors and recent years have witnessed the flourishing of studying the coevolution of cooperation and punishment, yet the common behavior of charity is seldom considered in game-theoretical models. In this article, we investigate the coevolution of altruistic cooperation and egalitarian charity in spatial public goods game, by considering charity as the behavior of reducing inter-individual payoff differences. Our model is that, in each generation of the evolution, individuals play games first and accumulate payoff benefits, and then each egalitarian makes a charity donation by payoff transfer in its neighborhood. To study the individual-level evolutionary dynamics, we adopt different strategy update rules and investigate their effects on charity and cooperation. These rules can be classified into two global rules: random selection rule in which individuals randomly update strategies, and threshold selection rule where only those with payoffs below a threshold update strategies. Simulation results show that random selection enhances the cooperation level, while threshold selection lowers the threshold of the multiplication factor to maintain cooperation. When charity is considered, it is incapable in promoting cooperation under random selection, whereas it promotes cooperation under threshold selection. Interestingly, the evolution of charity strongly depends on the dispersion of payoff acquisitions of the population, which agrees with previous results. Our work may shed light on understanding human egalitarianism.

  7. AN ANALYSIS ON THE ADVANTAGES OF COOPERATIVE LEARNING APPROACH IN TEACHING WRITING

    Directory of Open Access Journals (Sweden)

    Chamisah Chamisah

    2013-11-01

    Full Text Available This article aims to explain an analysis of cooperative learning approach advantages in teaching writing. Accordingly, learning writing by using cooperative learning makes the students easier in developing the ideas to write. This approach is more than just putting students into groups, but the students can work together, share information, and they are responsible for completion of the tasks in group as well. Besides, in this approach, the students can transfer their information and knowledge to the others and help each other in getting the ideas to develop in written communication during teaching-learning process.

  8. International cooperation

    International Nuclear Information System (INIS)

    2008-01-01

    In this chapter international cooperation of the Division for Radiation Safety, NPP Decommissioning and Radwaste Management of the VUJE, a. s. is presented. Very important is cooperation with the International Atomic Energy Agency. This cooperation has various forms - national and regional projects of technical cooperation, coordinated research activities, participation of our experts in preparation of the IAEA documentation etc.

  9. S-pairing in neutron matter: I. Correlated basis function theory

    International Nuclear Information System (INIS)

    Fabrocini, Adelchi; Fantoni, Stefano; Illarionov, Alexey Yu.; Schmidt, Kevin E.

    2008-01-01

    S-wave pairing in neutron matter is studied within an extension of correlated basis function (CBF) theory to include the strong, short range spatial correlations due to realistic nuclear forces and the pairing correlations of the Bardeen, Cooper and Schrieffer (BCS) approach. The correlation operator contains central as well as tensor components. The correlated BCS scheme of [S. Fantoni, Nucl. Phys. A 363 (1981) 381], developed for simple scalar correlations, is generalized to this more realistic case. The energy of the correlated pair condensed phase of neutron matter is evaluated at the two-body order of the cluster expansion, but considering the one-body density and the corresponding energy vertex corrections at the first order of the Power Series expansion. Based on these approximations, we have derived a system of Euler equations for the correlation factors and for the BCS amplitudes, resulting in correlated nonlinear gap equations, formally close to the standard BCS ones. These equations have been solved for the momentum independent part of several realistic potentials (Reid, Argonne v 14 and Argonne v 8 ' ) to stress the role of the tensor correlations and of the many-body effects. Simple Jastrow correlations and/or the lack of the density corrections enhance the gap with respect to uncorrelated BCS, whereas it is reduced according to the strength of the tensor interaction and following the inclusion of many-body contributions

  10. Legislation on university technology transfer and research management 2012

    International Nuclear Information System (INIS)

    2012-02-01

    This book deals with legislation on university technology transfer in 2012, which includes invention promotion act, legislation on technology transfer and promotion of industrialization, legislation on industrial education and industrial cooperation, and special legislation on venture business. It lists the legislation related research and development by government department : fundamental law of scientific technique, law on evaluation and management of domestic research development business, national science and technology council and the patent office.

  11. Radiation-mediated Shocks in Gamma-Ray Bursts: Pair Creation

    Science.gov (United States)

    Lundman, Christoffer; Beloborodov, Andrei M.; Vurm, Indrek

    2018-05-01

    Relativistic sub-photospheric shocks are a possible mechanism for producing prompt gamma-ray burst (GRB) emission. Such shocks are mediated by scattering of radiation. We introduce a time-dependent, special relativistic code which dynamically couples Monte Carlo radiative transfer to the flow hydrodynamics. The code also self-consistently follows electron–positron pair production in photon–photon collisions. We use the code to simulate shocks with properties relevant to GRBs. We focus on plane-parallel solutions, which are accurate deep below the photosphere. The shock generates a power-law photon spectrum through the first-order Fermi mechanism, extending upward from the typical upstream photon energy. Strong (high Mach number) shocks produce rising νF ν spectra. We observe that in non-relativistic shocks the spectrum extends to {E}\\max ∼ {m}e{v}2, where v is the speed difference between the upstream and downstream. In relativistic shocks the spectrum extends to energies E> 0.1 {m}e{c}2 where its slope softens due to Klein–Nishina effects. Shocks with Lorentz factors γ > 1.5 are prolific producers of electron–positron pairs, yielding hundreds of pairs per proton. The main effect of pairs is to reduce the shock width by a factor of ∼ {Z}+/- -1. Most pairs annihilate far downstream of the shock, and the radiation spectrum relaxes to a Wien distribution, reaching equilibrium with the plasma at a temperature determined by the shock jump conditions and the photon number per proton. We discuss the implications of our results for observations of radiation generated by sub-photospheric shocks.

  12. Computing algebraic transfer entropy and coupling directions via transcripts

    Science.gov (United States)

    Amigó, José M.; Monetti, Roberto; Graff, Beata; Graff, Grzegorz

    2016-11-01

    Most random processes studied in nonlinear time series analysis take values on sets endowed with a group structure, e.g., the real and rational numbers, and the integers. This fact allows to associate with each pair of group elements a third element, called their transcript, which is defined as the product of the second element in the pair times the first one. The transfer entropy of two such processes is called algebraic transfer entropy. It measures the information transferred between two coupled processes whose values belong to a group. In this paper, we show that, subject to one constraint, the algebraic transfer entropy matches the (in general, conditional) mutual information of certain transcripts with one variable less. This property has interesting practical applications, especially to the analysis of short time series. We also derive weak conditions for the 3-dimensional algebraic transfer entropy to yield the same coupling direction as the corresponding mutual information of transcripts. A related issue concerns the use of mutual information of transcripts to determine coupling directions in cases where the conditions just mentioned are not fulfilled. We checked the latter possibility in the lowest dimensional case with numerical simulations and cardiovascular data, and obtained positive results.

  13. A Project in Support of Nuclear Technology Cooperation

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Deok Ku; Kim, Kyoung Pyo; Ko, Young Chel (and others)

    2006-12-15

    Establish strategies of international cooperation in an effect to promote our nation's leading role in international society, to form the foundation for the effective transfer of nuclear technology to developing countries, and to cope with the rapidly changing international nuclear climate. Using the INIS output data, it has provided domestic users with searching. Establish the integrated management system of information resources and to automate business flow and to improve business productivity through efficient information sharing.

  14. Exotic pairing in 1D spin-3/2 atomic gases with SO(4 symmetry

    Directory of Open Access Journals (Sweden)

    Yuzhu Jiang

    2015-06-01

    Full Text Available Tuning interactions in the spin singlet and quintet channels of two colliding atoms could change the symmetry of the one-dimensional spin-3/2 fermionic systems of ultracold atoms while preserving the integrability. Here we find a novel SO(4 symmetry integrable point in the spin-3/2 Fermi gas and derive the exact solution of the model using the Bethe ansatz. In contrast to the model with SU(4 and SO(5 symmetries, the present model with SO(4 symmetry preserves spin singlet and quintet Cooper pairs in two sets of SU(2⊗SU(2 spin subspaces. We obtain full phase diagrams, including the Fulde–Ferrel–Larkin–Ovchinnikov like pair correlations, spin excitations and quantum criticality through the generalized Yang–Yang thermodynamic equations. In particular, various correlation functions are calculated by using finite-size corrections in the frame work of conformal field theory. Moreover, within the local density approximation, we further find that spin singlet and quintet pairs form subtle multiple shell structures in density profiles of the trapped gas.

  15. Possible antipolar pairing mechanism in high-temperature superconductors

    International Nuclear Information System (INIS)

    Cardwell, D.A.; Shorrocks, N.M.

    1989-01-01

    An antipolar pairing mechanism for free charge carriers in high-T c superconducting compounds is proposed qualitatively. This involves the establishment of a two-dimensional (2D) array of effective charge-coupling centers within the superconducting lattice via a specific phonon distortion of cation species along a nonmajor crystallographic direction. A fundamental requirement of this model is that the density of such coupling centers decreases with decreasing temperature. In the case of Y-Ba-Cu-O, it is asserted that charge carriers in a 2D oxygen band adjacent to the phonon-containing plane become localized by the resulting (local) field distortion. Cooper pairs may then form when the charge-coupling-center density falls below the charge-carrier density. Such a mechanism could be mediated by a longitudinal phonon which softens at low temperatures to produce an antipolar state, such as that incipient to an antiferroelectric distortion of the lattice (i.e., in the zero-frequency limiting case). This model, which may be investigated experimentally by low-temperature Raman spectroscopy, isotopic substitution, and x-ray diffractometry at 4.2 K, can be applied to all p-type high-T c systems. In addition, it may account for the observed lattice anisotropy and short coherence length characteristic of these materials

  16. Zero-Shot Style Transfer in Text Using Recurrent Neural Networks

    OpenAIRE

    Carlson, Keith; Riddell, Allen; Rockmore, Daniel

    2017-01-01

    Zero-shot translation is the task of translating between a language pair where no aligned data for the pair is provided during training. In this work we employ a model that creates paraphrases which are written in the style of another existing text. Since we provide the model with no paired examples from the source style to the target style during training, we call this task zero-shot style transfer. Herein, we identify a high-quality source of aligned, stylistically distinct text in Bible ve...

  17. Polymer solidification: Technology transfer to DOE and industry

    International Nuclear Information System (INIS)

    Kalb, P.D.; Strand, G.

    1994-01-01

    In keeping with the congressional mandate for technology transfer between federal research and development institutions and U.S. industry, the Brookhaven National Laboratory (BNL) Environmental and Waste Technology Center is pursuing industrial partnership with industry. These efforts, supported by the Department of Energy's Office of Environmental Restoration and Waste Management involve both the transfer of BNL developed technology to industry and the use of commercially developed technologies as part of an integrated waste treatment system. A Cooperative Research and Development Agreement has been established with VECTRA Technologies, Inc. (formerly Pacific Nuclear), a U.S. company that provides waste treatment and other services to the commercial nuclear power industry. The agreement involves investigation of polyethylene encapsulation for treatment of ion exchange resin wastes. In addition, other avenues of cooperation are being investigated including use of a VECTRA Technologies volume reduction pre-treatment process for use with the polyethylene technology in treating aqueous radioactive, hazardous, and mixed wastes

  18. Reports on memorial lecture meetings on co-operative application finish of the SF cyclotron and its result reports

    International Nuclear Information System (INIS)

    2000-01-01

    The SF cyclotron at the Institute for Nuclear Study (INS) of University of Tokyo began its co-operative application in 1997 to continue its smooth operation during 21 years reaching March, 1997. Together with improvement of INS organization on April, 1997, it was transferred to the Center for Nuclear Study School of Science, University of Tokyo, INS continued a co-operative research for two years thereafter with Tanashi campus of the High Energy Accelerator Research Organization also established on April, 1997. This co-operative research was finished without accident at the end of March, 1999, to close history of co-operative application of cyclotron during 23 years. This report contains 15 memorial lecture and convivial meeting reports at the co-operative application finish of cyclotron and some results of co-operative applications and experiments, during 23 years. (G.K.)

  19. Insights into the energy transfer mechanism in Ce3+-Yb3+ codoped YAG phosphors

    NARCIS (Netherlands)

    Yu, D. C.; Rabouw, F. T.|info:eu-repo/dai/nl/413318036; Boon, W. Q.; Kieboom, T.; Ye, S.; Zhang, Q. Y.; Meijerink, A.|info:eu-repo/dai/nl/075044986

    2014-01-01

    Two distinct energy transfer (ET) mechanisms have been proposed for the conversion of blue to near-infrared (NIR) photons in YAG:Ce3+,Yb3+. The first mechanism involves downconversion by cooperative energy transfer, which would yield two NIR photons for each blue photon excitation. The second

  20. Generalized pairing strategies-a bridge from pairing strategies to colorings

    Directory of Open Access Journals (Sweden)

    Győrffy Lajos

    2016-12-01

    Full Text Available In this paper we define a bridge between pairings and colorings of the hypergraphs by introducing a generalization of pairs called t-cakes for t ∈ ℕ, t ≥ 2. For t = 2 the 2-cakes are the same as the well-known pairs of system of distinct representatives, that can be turned to pairing strategies in Maker-Breaker hypergraph games, see Hales and Jewett [12]. The two-colorings are the other extremity of t-cakes, in which the whole ground set of the hypergraph is one big cake that we divide into two parts (color classes. Starting from the pairings (2-cake placement and two-colorings we define the generalized t-cake placements where we pair p elements by q elements (p, q ∈ ℕ, 1 ≤ p, q < t, p + q = t.

  1. Nuclear technology transfer adapted to the needs of developing countries

    International Nuclear Information System (INIS)

    Martin, A.; Nentwich, D.

    1983-01-01

    The paper explains the build-up of nuclear know-how in the Federal Republic of Germany after 1955, when activities in the nuclear field became permitted. Furthermore, it shows the development of nuclear technology transfer via the increasing number of nuclear power plants exported. The inevitable interrelationship between the efficient transfer of know-how and long-term nuclear co-operation is demonstrated. Emphasis is put on the adaptation of nuclear technology transfer to the needs of the recipient countries. Guidelines to achieve the desired goal are given. (author)

  2. From bare to renormalized order parameter in gauge space: Structure and reactions

    Science.gov (United States)

    Potel, G.; Idini, A.; Barranco, F.; Vigezzi, E.; Broglia, R. A.

    2017-09-01

    It is not physically obvious why one can calculate with similar accuracy, as compared to the experimental data, the absolute cross section associated with two-nucleon transfer processes between members of pairing rotational bands, making use of simple BCS (constant matrix elements) or of many-body [Nambu-Gorkov (NG), nuclear field theory (NFT)] spectroscopic amplitudes. Restoration of spontaneous symmetry breaking and associated emergent generalized rigidity in gauge space provides the answer and points to a new emergence: A physical sum rule resulting from the intertwining of structure and reaction processes, closely connected with the central role induced pairing interaction plays in structure, together with the fact that successive transfer dominates Cooper pair tunneling.

  3. Incentive Model Based on Cooperative Relationship in Sustainable Construction Projects

    Directory of Open Access Journals (Sweden)

    Guangdong Wu

    2017-07-01

    Full Text Available Considering the cooperative relationship between owners and contractors in sustainable construction projects, as well as the synergistic effects created by cooperative behaviors, a cooperative incentive model was developed using game theory. The model was formulated and analyzed under both non-moral hazard and moral hazard situations. Then, a numerical simulation and example were proposed to verify the conclusions derived from the model. The results showed that the synergistic effect increases the input intensity of one party’s resource transfer into the increase of marginal utility of the other party, thus the owner and contractor are willing to enhance their levels of effort. One party’s optimal benefit allocation coefficient is positively affected by its own output efficiency, and negatively affected by the other party’s output efficiency. The effort level and expected benefits of the owner and contractor can be improved by enhancing the cooperative relationship between the two parties, as well as enhancing the net benefits of a sustainable construction project. The synergistic effect cannot lower the negative effect of moral hazard behaviors during the implementation of sustainable construction projects. Conversely, the higher levels of the cooperative relationship, the wider the gaps amongst the optimal values under both non-moral hazard and moral hazard situations for the levels of effort, expected benefits and net project benefits. Since few studies to date have emphasized the effects of cooperative relationship on sustainable construction projects, this study constructed a game-based incentive model to bridge the gaps. This study contributes significant theoretical and practical insights into the management of cooperation amongst stakeholders, and into the enhancement of the overall benefits of sustainable construction projects.

  4. IAEA technical co-operation activities in the 1990s

    International Nuclear Information System (INIS)

    1995-01-01

    The desire to extend the many benefits of the peaceful uses of nuclear technology to all countries led as long ago as 1957 to the establishment of the IAEA and to immediate introduction of a technical co-operation programme. In the more than thirty years that have passed since that time, the potential applications of nuclear techniques have greatly expanded. Over the period, many of the applications have moved from research laboratories into hospitals, farms and industrial enterprises. The direct resources made available to the IAEA by its Member States to support technology transfer processes have grown rapidly since the late 1950s. The current trends in the technical co-operation activities of the IAEA and some examples of projects supported by the IAEA are briefly presented in this document

  5. Non-cooperative game theory in biology and cooperative reasoning in humans.

    Science.gov (United States)

    Kabalak, Alihan; Smirnova, Elena; Jost, Jürgen

    2015-06-01

    The readiness for spontaneous cooperation together with the assumptions that others share this cooperativity has been identified as a fundamental feature that distinguishes humans from other animals, including the great apes. At the same time, cooperativity presents an evolutionary puzzle because non-cooperators do better in a group of cooperators. We develop here an analysis of the process leading to cooperation in terms of rationality concepts, game theory and epistemic logic. We are, however, not attempting to reconstruct the actual evolutionary process. We rather want to provide the logical structure underlying cooperation in order to understand why cooperation is possible and what kind of reasoning and beliefs would lead to cooperative decision-making. Game theory depends on an underlying common belief in non-cooperative rationality of the players, and cooperativity similarly can utilize a common belief in cooperative rationality as its basis. We suggest a weaker concept of rational decision-making in games that encompasses both types of decision-making. We build this up in stages, starting from simple optimization, then using anticipation of the reaction of others, to finally arrive at reflexive and cooperative reasoning. While each stage is more difficult than the preceding, importantly, we also identify a reduction of complexity achieved by the consistent application of higher stage reasoning.

  6. Designing for cooperation - cooperating in design

    DEFF Research Database (Denmark)

    Kyng, Morten

    1991-01-01

    This article will discuss how to design computer applications that enhance the quality of work and products, and will relate the discussion to current themes in the field of Computer-Supported Cooperative Work (CSCW). Cooperation is a key element of computer use and work practice, yet here...... a specific "CSCW approach is not taken." Instead the focus is cooperation as an important aspect of work that should be integrated into most computer support efforts in order to develop successful computer support, however, other aspects such as power, conflict and control must also be considered....

  7. Efficient and Provable Secure Pairing-Free Security-Mediated Identity-Based Identification Schemes

    Directory of Open Access Journals (Sweden)

    Ji-Jian Chin

    2014-01-01

    Full Text Available Security-mediated cryptography was first introduced by Boneh et al. in 2001. The main motivation behind security-mediated cryptography was the capability to allow instant revocation of a user’s secret key by necessitating the cooperation of a security mediator in any given transaction. Subsequently in 2003, Boneh et al. showed how to convert a RSA-based security-mediated encryption scheme from a traditional public key setting to an identity-based one, where certificates would no longer be required. Following these two pioneering papers, other cryptographic primitives that utilize a security-mediated approach began to surface. However, the security-mediated identity-based identification scheme (SM-IBI was not introduced until Chin et al. in 2013 with a scheme built on bilinear pairings. In this paper, we improve on the efficiency results for SM-IBI schemes by proposing two schemes that are pairing-free and are based on well-studied complexity assumptions: the RSA and discrete logarithm assumptions.

  8. Efficient and provable secure pairing-free security-mediated identity-based identification schemes.

    Science.gov (United States)

    Chin, Ji-Jian; Tan, Syh-Yuan; Heng, Swee-Huay; Phan, Raphael C-W

    2014-01-01

    Security-mediated cryptography was first introduced by Boneh et al. in 2001. The main motivation behind security-mediated cryptography was the capability to allow instant revocation of a user's secret key by necessitating the cooperation of a security mediator in any given transaction. Subsequently in 2003, Boneh et al. showed how to convert a RSA-based security-mediated encryption scheme from a traditional public key setting to an identity-based one, where certificates would no longer be required. Following these two pioneering papers, other cryptographic primitives that utilize a security-mediated approach began to surface. However, the security-mediated identity-based identification scheme (SM-IBI) was not introduced until Chin et al. in 2013 with a scheme built on bilinear pairings. In this paper, we improve on the efficiency results for SM-IBI schemes by proposing two schemes that are pairing-free and are based on well-studied complexity assumptions: the RSA and discrete logarithm assumptions.

  9. International cooperation and technology transfer for coal and power development in ASEAN

    Energy Technology Data Exchange (ETDEWEB)

    Husin, Z.A. (Tenaga Nasional Berhad (Malaysia))

    1991-12-01

    Coal resources in the ASEAN region are being developed to meet the forecast rise in electricity demand of 9% per year to 2000. From a virtual non-existence in the early 1980s, it is hoped that coal will provide up to 37% of increased power plant capacity. Close cooperation with industrialised countries outside the region are necessary to help overcome the pressures being put on available energy and financial resources, technological knowledge, and the environment. 13 refs., 5 figs.

  10. Transfer of High Performance Liquid Chromatography with Diode ...

    African Journals Online (AJOL)

    2013-08-22

    Aug 22, 2013 ... Rwanda Journal Series F:Medicine and Health Sciences Vol 4 No.1, 2017 ... 1Laboratory of Analysis of Foodstuffs, Drugs, Water and Toxics, University of Rwanda, School of Medicine and Pharmacy, 117 Huye, ..... Cooperation for the financial support. .... for the transfer of quantitative methods: Bioanalytical.

  11. Transfer of suspended particles from liquid effluents of nuclear generating stations through the environment

    International Nuclear Information System (INIS)

    Devereaux, F.J.

    1989-07-01

    Due to the complexity of the environmental transfer of suspended particles in aquatic systems, the available literature usually deals with specific pathways and mechanisms of the transfer process. This paper attempts to give a brief overview of the entire transfer process. Potential routes of transfer in both the marine and freshwater environments are examined, and tentative conclusions presented. This work was performed while the author was employed by Atomic Energy Control Board under the McMaster University cooperative program

  12. Structural features in the HIV-1 repeat region facilitate strand transfer during reverse transcription

    NARCIS (Netherlands)

    Berkhout, B.; Vastenhouw, N. L.; Klasens, B. I.; Huthoff, H.

    2001-01-01

    Two obligatory DNA strand transfers take place during reverse transcription of a retroviral RNA genome. The first strand transfer is facilitated by terminal repeat (R) elements in the viral genome. This strand-transfer reaction depends on base pairing between the cDNA of the 5'R and the 3'R. There

  13. Weathering the competition through cooperation at customer service level; Erfolgreich im Wettbewerb durch Kooperation im Kundenservice

    Energy Technology Data Exchange (ETDEWEB)

    Quante, Katrin [VISOS GmbH, Moers (Germany)

    2012-01-15

    Rising customer churn rates in the wake of stiffening competition are aggravating the cost pressure on energy supply companies. More and more energy suppliers are seeking cooperations as a means of countering the growing cost pressure, rapidity of change and growing complexity of their workflows. Especially small and medium-sized utilities see this as an appropriate means of holding their own against large energy suppliers. In other branches of industry inter-company cooperations at the economic or technical level are already established practice. Recent project experiences have shown that such cooperation models can be transferred with equal success to the energy sector at customer service level.

  14. Exploring the Mechanisms of Knowledge Transfer in University-Industry Collaborations

    DEFF Research Database (Denmark)

    Nielsen, Christian; Cappelen, Katja

    2014-01-01

    respondents have been involved in collaborative projects, such as student-industry cooperation or collaboration projects between scientists and businesses. This research shows that to secure real value adding through knowledge transfer in universityindustry collaboration projects, it is important...

  15. TANDEM - French-German cooperation for local energy transition

    International Nuclear Information System (INIS)

    Mouchard, Claire; Garreau, Enora; Maurer, Christiane; Schilken, Peter; Keilmann, Jenny-Claire; Janssen, Ulrike

    2014-01-01

    The simultaneous implementation of the German 'Energiewende' and the French 'Transition energetique' prompted both country's governments to sign various cooperation agreements. As both 'Energiewende' and 'Transition energetique' put a strong focus on decentralization of energy supply, establishing close inter-communal cooperation is particularly promising. The project TANDEM, which is jointly led by Klima-Buendnis and Energy Cities - both local authority networks - and co-funded by Germany's Federal Environment Agency (UBA) and the French Energy Agency ADEME provides French and German local authorities with a unique opportunity to exchange experiences and create partnerships for climate protection having the following objectives: - Creating broad mutual understanding for the respective situation, challenges and framework in energy and climate policy; - Encourage exchanges with regard to obstacles and success factors concerning the realization of ambitious energy- and climate-goals and promoting mutual transfer of know-how; - Stimulating close collaboration between local authorities from both countries while involving and supporting local stakeholders and citizens; - Implementing initial stages of cooperation projects during the lifetime of the TANDEM project and creating a foundation for long-term cooperation; - Raise awareness for demands, requirements and concerns of local authorities on a national and European level in order to strengthen their influence and enlarge their scope of action. In this document, the authors briefly present the French, German and European contexts and the organization of both countries regarding energy transition. Then, a parallel is made between the national energy-climate plans of both countries ('Klimaschutzkonzepte' and 'Plans Climat-Energie Territoriaux') to identify the similarities and differences in order to learn from each other and to be able to create cooperations between both policy mechanisms

  16. Effects of R&D Cooperation to Innovation Performance in Open Innovation Environment

    Directory of Open Access Journals (Sweden)

    Gao Liang

    2014-05-01

    Full Text Available Dynamic nonlinear characteristics of internal and external environment in modern organization shows up increasingly, which make innovative research breakthrough organizational boundaries and present a pattern of open mode, the traditional mode of innovation is facing huge challenges like increasing innovation cycle, huge R&D input and inefficient knowledge transfer. And cooperation with external organizations to implement R&D is definitely a possibility to solve the open innovation environment challenge. Since organizations often have multiple dimensions of cooperation with different types of organization for research and development for the influence of organizational innovation performance or for exploring cooperation at the same time in different areas, and in different types of institutions. This paper studied the innovation performance of relevant government agencies except such innovation organization as enterprises, universities, and research institutions for the first time. This paper tracked on a survey of China's national engineering technology research center in related situation from 2002 to 2011 and collected related data to research and development cooperation and innovation performance for empirical research. Study found that universities have advantages in richness, in knowledge itself and knowledge accessible extent, cooperation with university in R&D is the best choice to promote the innovation performance of the organization. While cooperating with domestic universities and domestic enterprises to carry out research and development has bad effect in organizational innovation performance; while cooperation with domestic institutions and foreign institutions in the research and development plays a positive role in promoting innovation.

  17. Importance of the single-particle continuum in BCS pairing with a pseudostate basis

    Directory of Open Access Journals (Sweden)

    Lay J. A.

    2016-01-01

    Full Text Available In a recent work [arXiv:1510.03185] the use of the Transformed Harmonic Oscillator (THO basis for the discretization of the singleparticle continuum into a Generalized Bardeen-Cooper-Schrieffer (BCS formalism was proposed for the description of weakly bound nuclei. We make use of the flexibility of this formalism to study the evolution of the pairing when the nucleus becomes more and more weakly bound. Specifically we focus on the evolution of the occupation of the different partial waves in 22O when the Fermi level approaches zero.

  18. A project in support of Nuclear Technology Cooperation

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Ki Jung; Choi, Pyong Hoon; Yi, Ji Ho [and others

    2005-12-15

    Establish the integrated management system of information resources and to automate business flow and to improve business productivity through efficient information sharing. - Promotion of domestic nuclear energy technology by utilizing nuclear energy informations and computer software developed in the advanced countries. - Establish strategies of international cooperation in an effort to promote our nation's Leading role in international society, to form the foundation for the effective transfer of nuclear technology to developing countries, and to cope with the rapidly changing international nuclear climate.

  19. A project in support of Nuclear Technology Cooperation

    International Nuclear Information System (INIS)

    Jung, Ki Jung; Choi, Pyong Hoon; Yi, Ji Ho

    2005-12-01

    Establish the integrated management system of information resources and to automate business flow and to improve business productivity through efficient information sharing. - Promotion of domestic nuclear energy technology by utilizing nuclear energy informations and computer software developed in the advanced countries. - Establish strategies of international cooperation in an effort to promote our nation's Leading role in international society, to form the foundation for the effective transfer of nuclear technology to developing countries, and to cope with the rapidly changing international nuclear climate

  20. Theory of coherent resonance energy transfer

    International Nuclear Information System (INIS)

    Jang, Seogjoo; Cheng, Y.-C.; Reichman, David R.; Eaves, Joel D.

    2008-01-01

    A theory of coherent resonance energy transfer is developed combining the polaron transformation and a time-local quantum master equation formulation, which is valid for arbitrary spectral densities including common modes. The theory contains inhomogeneous terms accounting for nonequilibrium initial preparation effects and elucidates how quantum coherence and nonequilibrium effects manifest themselves in the coherent energy transfer dynamics beyond the weak resonance coupling limit of the Foerster and Dexter (FD) theory. Numerical tests show that quantum coherence can cause significant changes in steady state donor/acceptor populations from those predicted by the FD theory and illustrate delicate cooperation of nonequilibrium and quantum coherence effects on the transient population dynamics.